Fellow retrieval specialist and Royal North Shore Hospital emergency physician Dr Toby Fogg and coauthors have published their audit of intubations in an Australian Emergency Department(1). More important than the results themselves is that the process of monitoring ones practice inevitably leads to improvements. For example, at Toby’s institution an intubation checklist has been introduced since the audit began. Other Australasian EDs are encouraged to participate using the free resources at airwayregistry.org.au.

Recently we have also seen the publication of Korean registry data on paediatric intubations performed in 13 academic EDs over 5 years(2), in which first pass success rates (overall 67.6%) were higher with emergency physicians compared with paediatricians. Interestingly, a rapid sequence intubation technique was only used in 22.4% of intubations, which was more likely to be used by emergency physicians and was associated with a greater likelihood of first pass success.

This relatively low first pass success rate is reminiscent of the American study published in September(3) which raised some eyebrows with its 52% first pass intubation success rates in a paediatric ED, and which also showed that attending-level providers were 10 times more likely to be successful on the first attempt than all trainees combined. Possible reasons for such a low first pass success rate compared with adult registry data include the rigorous video analysis method used, or perhaps more likely that paediatric emergency subspecialists are exposed to fewer critical procedures, resuscitations, and intubations than their general emergency medicine counterparts(4).

As a specialty we must continue to seek to do better, and I salute all these brave authors who are telling it like it is. Particularly with children, whose airways are relatively easy, we have to develop the training, preparation, supervision, monitoring and feedback to aim for as high a success rate as possible.

Study authors Toby Fogg and Nick Annesley demonstrate the 'Happiness Triad'

1. Prospective observational study of the practice of endotracheal intubation in the emergency department of a tertiary hospital in Sydney, Australia
Emerg Med Australas. 2012 Dec;24(6):617-24
Click to read abstract

2. The factors associated with successful paediatric endotracheal intubation on the first attempt in emergency departments: a 13-emergency-department registry study
Resuscitation. 2012 Nov;83(11):1363-8
Click to read abstract

3.Rapid sequence intubation for pediatric emergency patients: higher frequency of failed attempts and adverse effects found by video review.
Ann Emerg Med. 2012 Sep;60(3):251-9
Click to read abstract

4. A is for airway: a pediatric emergency department challenge.
Ann Emerg Med. 2012 Sep;60(3):261-3

Ever been at a cardiac arrest resuscitation where someone’s opening and closing drawers at great speed but failing to retrieve the drugs or equipment you’ve asked for urgently?

What if your resus trolley were designed by team of clinicians, engineers, and designers? Such a project was achieved through a collaboration between Imperial College London and the Helen Hamlyn Centre for Design, and the award-winning result was called the ‘Resus:Station’.

The trolley separates into three trolleys for airway, drugs and defibrillation, and circulation. The contents are visible from the outside.

Image from Pubmed Free Full Text Article

As well as improving access to equipment, the trolley can log the team’s actions during each resuscitation attempt. It can also provide an instant display of its readiness for use by recording the removal and replacement of each item.

In a randomised comparison with a standard resus trolley, a number of measures of efficiency and team performance were significantly better using the Resus:Station during simulated cardiac arrest resuscitations.

It appears to be specifically designed for cardiac arrest situations rather than ‘resus’ in its wider context. The most recent article (cited below) reports that a newer prototype is being developed prior to the manufacture of the final product.

For an in depth discussion of how resus room layout can optimise efficiency, check out Minh Le Cong’s PHARM blog and podcast with James French and Scott Weingart on Clinical Logistics

The “Resus:Station”: the use of clinical simulations in a randomised crossover study to evaluate a novel resuscitation trolley.
Resuscitation. 2012 Nov;83(11):1374-80 Free full text
Click for abstract

A study on data from traumatic brain injury patients from the the TARN database examined the prognostic value of various scoring and classification systems and pathologies.

Contusion and haemorrhage appeared to be less significant predictors of outcome than the presence of brain swelling in this British dataset.

The brainstem was the most significant location of cerebral injury.

Prognostic value of various intracranial pathologies in traumatic brain injury
European Journal of Trauma and Emergency Surgery February 2012, Volume 38, Issue 1, pp 25-32
Click for abstract

A subset of patients from the 2008 Vasopressin and Septic Shock Trial (VASST) trial had invasive haemodynamic monitoring measurements from pulmonary artery catheters. These data have now been analysed, revealing that vasopressin was associated with a lower heart rate compared with norepinephrine (noradrenaline) alone, without significant difference in cardiac index or stroke volume index. However, there was significantly greater use of inotropic drugs in the vasopressin group compared with the norepinephrine group.

Tachycardia and high quantities of catecholamine infusion are both associated with mortality in sepsis. The authors discuss:

“The idea of decatecholaminization, reducing both endogenous and exogenous adrenergic stimulation, is now believed to be an important treatment strategy, and the use of beta-blockers in septic shock is being considered. The early use of vasopressin or specific V1a receptor agonists in early septic shock may be another possible treatment.”

This interesting post-hoc analysis may help further define the patients in whom vasopressin is to be considered, by those clinicians who are using it in septic shock. For those that aren’t, I wouldn’t worry about it.

The cardiopulmonary effects of vasopressin compared with norepinephrine in septic shock
Chest. 2012 Sep;142(3):593-605
Click for abstract

I was lucky to be accompanied through much of my emergency medicine training and specialist work in the UK by Bruce Armstrong. We shared many resuscitation cases together in hospitals and in prehospital care.

When preparing the team in resus, Armstrong used to appoint a ‘safety officer’. This could be a nurse or physician – it didn’t matter. Their role was to stay hands-off and be the eyes, ears, and mouth that would identify impending hazards and verbally intervene to thwart them.

This process seemed so natural that I rarely gave it a thought, but its glaring absence from every place I’ve worked since has only recently hit me.

Because my son goes swimming.

My three year old son attends a swimming class. There is usually one other child in the class. Recently a third child joined the class and I found myself getting uncomfortable. How could the instructor stay vigilant? What if while holding one child one of the others sank under water out of her field of view? My own obsessive reading about the limitations of human perception and cognition has convinced me that no-one can really focus on more than one thing at a time.

A friend of mine has coached kids at swimming so I asked him how they solve this. The answer was obvious – you rely on the life guards whose sole role is look out for everyone’s safety. Duh.

And then it came to me. Armstrong knew this all along. He got this idea from his prehospital experience working with fire & rescue crews and brought it into the ED. It didn’t occur to me that no-one else did this. It was just him.

Keen to explore whether anyone else had embraced this idea, I decided to go to the top when it comes to patient safety, and contacted Martin Bromiley. He told me he hadn’t come across the role in this specific setting, although did point out a great example from the BBC Documentary ‘Operation Iceberg’, in which ‘a group of scientists boarded an iceberg with someone watching over the big picture of polar bears and the berg cracking as well as fog etc’. Martin directed me to the Clinical Human Factors Group on LinkedIn, where interest was shown in the concept although it was apparent others haven’t come across it.

I went back to Armstrong to push him on further thoughts:

Yes a thought….in every other high risk environment they have a specific safety officer, whether it be nuclear industry, airline etc.

The role is specific not an add on to another role.

In healthcare we are seen as successful the more we do by one person. Think lean… think ‘efficiencies’ in the health service. Other industries focus on safety. Get safety right, your brand is safe and the public go with you. If you don’t put safety first it is only a matter of time before disaster strikes. In healthcare we have too many serious incidents. The time has come to believe in and practice safety in health care rather than ticking boxes and not applying CRM and human factors.

One such example from industry shows that safety officers may use checklists, such as this one from the Australian Maritime Safety Authority in response to an oil spill.

So here’s a proposed one for a Resuscitation Room Safety Officer. It’s a first draft to get the idea out there and start the conversation – just click the image below to enlarge. I’ve written (and used) checklists in resus before, but none specifically for a safety officer.

I would like to hear if anyone’s already doing this anywhere, and how it’s been working.

Cliff

Primary percutaneous coronary intervention or fibrinolysis for STEMI? What if you don’t have PCI at your hospital?

The new 2013 ACCF/AHA Guideline for the Management of ST-Elevation Myocardial Infarction is out and you can get the summary here.

Here’s what they say about initial reperfusion therapy:

Onset of Myocardial Infarction: Recommendations
Regional Systems of STEMI Care, Reperfusion Therapy, and Time-to-Treatment Goals

Class I

1. All communities should create and maintain a regional system of STEMI care that includes assessment and continuous quality improvement of emergency medical services and hospital-based activities. Performance can be facilitated by participating in programs such as Mission: Lifeline and the Door-to-Balloon Alliance.(Level of Evidence: B)

2. Performance of a 12-lead electrocardiogram (ECG) by emergency medical services personnel at the site of first medical contact (FMC) is recommended in patients with symptoms consistent with STEMI.(Level of Evidence: B)

3. Reperfusion therapy should be administered to all eligible patients with STEMI with symptom onset within the prior 12 hours. (Level of Evidence: A)

4. Primary PCI is the recommended method of reper- fusion when it can be performed in a timely fashion by experienced operators. (Level of Evidence: A)

5. Emergency medical services transport directly to a PCI-capable hospital for primary PCI is the recommended triage strategy for patients with STEMI, with an ideal FMC-to-device time system goal of 90 minutes or less.(Level of Evidence: B)

6. Immediate transfer to a PCI-capable hospital for primary PCI is the recommended triage strategy for patients with STEMI who initially arrive at or are transported to a non–PCI-capable hospital, with an FMC-to-device time system goal of 120 minutes or less.(Level of Evidence: B)

7. In the absence of contraindications, fibrinolytic therapy should be administered to patients with STEMI at non–PCI-capable hospitals when the anticipated FMC-to-device time at a PCI-capable hospital exceeds 120 minutes because of unavoidable delays.(Level of Evidence: B)

8. When fibrinolytic therapy is indicated or chosen as the primary reperfusion strategy, it should be administered within 30 minutes of hospital arrival.(Level of Evidence: B)

Class IIa

1. Reperfusion therapy is reasonable for patients with STEMI and symptom onset within the prior 12 to 24 hours who have clinical and/or ECG evidence of ongoing ischemia. Primary PCI is the preferred strategy in this population. (Level of Evidence: B)

2013 ACCF/AHA Guideline for the Management of ST-Elevation Myocardial Infarction: Executive Summary: A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines.
Circulation. 2012 Dec 17. [Epub ahead of print]

High intensity focused ultrasound (HIFU) was hailed as the ‘surgery of the future’ a few years ago(1). As it’s now the future, where is it?

HIFU uses ultrasound to increase the heat within tissues at a specific area, causing local necrosis and cautery without injuring surrounding tissues. It is used to treat some cancers, but has shown promise in haemorrhage control. In animal studies it reduced or stopped bleeding in liver(2), spleen(3), and vascular injuries(4).

It has been proposed to offer a promising method for hemorrhage control in both civilivan and miltary trauma(5). Automated systems have been developed and tested that identify bleeding using Doppler ultrasound techniques that then allow targeting of the HIFU beam to the bleeding tissue(6). The United States Army has identified the need for a such systems and has designed a remotely operated robotic haemostatic system to save lives of soldiers. This was presented in 2006(7).

I would love to know where we are with this technology, and why nothing seems to have appeared about it in the literature for the last few years. If you have any information, please fill us in via the comments box.

1. High intensity focused ultrasound: surgery of the future?
Br J Radiol. 2003 Sep;76(909):590-9 Full text

2. Liver hemostasis using high-intensity focused ultrasound
Ultrasound Med Biol. 1997;23(9):1413-20

3. Control of splenic bleeding by using high intensity ultrasound
J Trauma. 1999 Sep;47(3):521-5

4. Hemostasis of punctured blood vessels using high-intensity focused ultrasound
Ultrasound Med Biol. 1998 Jul;24(6):903-10

5. Hemorrhage control using high intensity focused ultrasound
Int J Hyperthermia. 2007 Mar;23(2):203-11

6. Focused ultrasound: concept for automated transcutaneous control of hemorrhage in austere settings.
Aviat Space Environ Med. 2009 Apr;80(4):391-4

7. Remotely Operated Robotic High Intensity Focused Ultrasound (HIFU) Manipulator System for Critical Systems for Trauma and Transport (CSTAT)
Presented at the IEEE Ultrasonics Symposium, October 3-6, 2006, Vancouver, Canada – Full Text Here

A South American randomised controlled trial has demonstrated no improvement in mortality when traumatic brain injured patients had therapy targeted at keeping intracranial pressure below or equal to 20 mmHg as measured by an intraparenchymal monitor. The control group’s management was guided by neurologic examination and serial CT imaging(1).

Editorialist Dr Ropper summarises what we should do with this information well(2):

“[The authors]…do not advocate abandoning the treatment of elevated intracranial pressure any more than the authors of studies on wedge pressure reject the administration of fluid boluses in the treatment of shock”

BACKGROUND

Intracranial-pressure monitoring is considered the standard of care for severe traumatic brain injury and is used frequently, but the efficacy of treatment based on monitoring in improving the outcome has not been rigorously assessed.

METHODS
We conducted a multicenter, controlled trial in which 324 patients 13 years of age or older who had severe traumatic brain injury and were being treated in intensive care units (ICUs) in Bolivia or Ecuador were randomly assigned to one of two specific protocols: guidelines-based management in which a protocol for monitoring intraparenchymal intracranial pressure was used (pressure-monitoring group) or a protocol in which treatment was based on imaging and clinical examination (imaging–clinical examination group). The primary outcome was a composite of survival time, impaired consciousness, and functional status at 3 months and 6 months and neuropsychological status at 6 months; neuropsychological status was assessed by an examiner who was unaware of protocol assignment. This composite measure was based on performance across 21 measures of functional and cognitive status and calculated as a percentile (with 0 indicating the worst performance, and 100 the best performance).

RESULTS
There was no significant between-group difference in the primary outcome, a composite measure based on percentile performance across 21 measures of functional and cognitive status (score, 56 in the pressure-monitoring group vs. 53 in the imaging–clinical examination group; P=0.49). Six-month mortality was 39% in the pressure-monitoring group and 41% in the imaging–clinical examination group (P=0.60). The median length of stay in the ICU was similar in the two groups (12 days in the pressure-monitoring group and 9 days in the imaging–clinical examination group; P=0.25), although the number of days of brain-specific treatments (e.g., administration of hyperosmolar fluids and the use of hyperventilation) in the ICU was higher in the imaging–clinical examination group than in the pressure-monitoring group (4.8 vs. 3.4, P=0.002). The distribution of serious adverse events was similar in the two groups.

CONCLUSIONS
For patients with severe traumatic brain injury, care focused on maintaining monitored intracranial pressure at 20 mm Hg or less was not shown to be superior to care based on imaging and clinical examination

1. A Trial of Intracranial-Pressure Monitoring in Traumatic Brain Injury
N Eng J Med 367;26:2471-2381 Full Text

2. Brain in a Box
N Eng J Med DOI: 10.1056/NEJMe1212289 Full Text

“To date, approximately one-third of the women who die during pregnancy remain undelivered at the time of death”

Guidelines recommend cardiac arrest in pregnant women beyond 20 weeks gestation should be treated with perimortem caesarean delivery (PMCD) commenced within 4 minutes of arrest and completed within 5. These time intervals come from two papers, neither of which is current or used robust review methodology.

To address this, an up-to-date fairly comprehensive review was undertaken of published cases of maternal cardiac arrests occurring prior to delivery. The primary outcome measures were maternal and neonatal survival to hospital discharge and the relationship between PMCD and this outcome.

The Arrests

94 cases were included in the final analysis.Most pregnancies were singleton (90.4%, n = 85) with an average gestational age at the time of the arrest of 33 ± 7 weeks (median 35, range 10–42).

The most common causes of arrest were trauma, maternal cardiac problems, severe pre-eclampsia and amniotic fluid embolism, together comprising about 70% of arrests; two thirds occurred in hospital.

The Outcomes

Overall, return of spontaneous circulation (ROSC) was achieved more often than not (60.6%) and overall survival to hospital discharge was 54.3%

Only 57 cases (75%) reported the time from arrest to delivery; the average time was 16.6 ± 12.5 min (median 10, range 1–60), with only 4 cases making it under the advocated 4-min time limit.

Timing of PMCD and Maternal Survival

In cases undergoing PMCD the average time elapsing from arrest to PMCD was significantly different between surviving (27/57) and non-surviving (30/57) mothers [10.0 ± 7.2 min (median 9, range 1–37) and 22.6 ± 13.3 min (median 20, range 4–60) respectively (p < 0.001, 95%CI 6.9–18.2)].

Timing of PMCD and Neonatal Survival

Mean times to PMCD were 14±11min (median=10, range=1–47) and 22 ± 13 min (median = 20, range = 4–60) in neonatal survivors and non-survivors respectively (p=0.016)

In cases with PMCD which reported outcome, the overall neonatal survival rate was 63.6% (42/66).

“The 4-min time frame advocated for PMCD usually remains unmet yet neonatal survival is still likely if delivery occurs within 10 or even 15 min of arrest”

Both maternal & neonatal mortality were higher with prehospital arrest location.

Summary

The study may be limited by recall bias, under-reporting and publication bias, but provides a more comprehensive evidence base on which to base resuscitation recommendations. The authors provide a useful warning against becoming fixated with the recommended four minute window, which may lead teams to fail to attempt a potentially life-saving intervention:

“Fixation on specific time frames for PMCD may not be ideal. It may be more important to focus on event recognition and good overall performance…. It may be wise to advocate a short time frame for performance of PMCD in order to achieve better outcomes; however, blanket endorsement of an unrealistic time frame may well create a defeatist attitude when that time frame cannot be met.”

Maternal cardiac arrest and perimortem caesarean delivery: Evidence or expert-based?
Resuscitation. 2012 Oct;83(10):1191-200
Click for abstract

Notes from Day 4 of the London Trauma Conference

The highlight for me was Mr Jonny Morrison speaking on Resuscitative Emergency Balloon Occlusion of the Aorta (REBOA). He is a British military surgeon currently out in Texas studying balloon occlusion of the aorta on pigs. Looking at trauma deaths, the next unexpected survivors will come from the uncontrollable haemorrhage group (truncal and junctional zones). This is by no means a new technique – described in the 1950’s during the Korean War – but like the early Star Wars chapters, needed to wait for technology to advance to make it feasible. It has the effect of cross clamping the aorta which provides afterload support, increases cerebral and coronary perfusion and provides proximal inflow control – without the mess of a resuscitative thoracotomy and greater access.

The placement of the balloon is determined by the location of the injury (see photo) and falls into two zones. Zone 1 is the thoracic aorta and is used for truncal haemorrhage control, avoid Zone 2 where the celiac axis etc originates and Zone 3 is infrarenal, used for junctional bleeding and pelvic haemorrhage.

His studies have determined that for Zone 3 amenable bleeds balloon occlusion up to 60min is the optimal time. Any longer and the debt of the metabolic load is paid by increased inotropic support requirements. He also compared REBOA to the current standard treatment for junctional injuries, Celox™ gauze. If coagulation is normal then both treatments perform similarly, the benefit is seen in coagulopathic patients where REBOA outperforms the gauze.

Has REBOA been used on humans? Yes a case series of 13 – the technique improved the BP allowing time to get to definitive surgery (blogged here 2.5 years ago!).

The Zone 1 studies are looking at continuous vs intermittent balloon occlusion. The jury is still out as to which is better. With the intermittent occlusion (20min on, 1min off) there are inevitably some losses when the balloon is deflated, conversely the metabolic debt generated by continuous occlusion is too great in some also leading to deaths.

What was very clear is that for this technique to have an impact it must be delivered proactively and pre-hospital. The challenges that need to be overcome are access to the femoral artery and blind accurate placement.

Prof Karim Brohi brought the conference to a close with a summary of what we have learned about coagulation in trauma this year. Here are three things;

• FFP is good but as 43% deaths due to trauma in the UK are secondary to bleeding and occur in the first 3hr we are failing our patients by administering the treatment on average at 2.5hrs.

• Fibrinogen levels are low in coagulopathic trauma patients; we should give cryoprecipitate early and aim for Fib ≥2.0

• And finally whilst TEG is recommended to guide treatment and can provide results within 5 min, there are some aspects of coagulation it does not detect i.e. fibrinolysis was only detected in 8% of coagulopathic trauma patients – when measured in the plasma it was then detectable in 80%.

These are the highlights of the 2012 London Trauma Conference. I hope this whistle stop tour through these days has been informative and though provoking. I can assure you telephone hacking was not used to bring you this information and to my knowledge is correct.

This is Lou Chan, roving reporter for Resus ME! signing off.

 

‘London raises her head, shakes off the debris of the night from her hair, and takes stock of the damage done. The sign of a great fighter in the ring is can he get up from a fall after being knocked down… London does this every morning.’

Notes from Days 2 & 3 of the London Trauma Conference

Day 2 of the LTC was really good. There were some cracking speakers who clearly had the ‘gift’ when it comes to entertaining the audience. No death by PowerPoint here (although it seems Keynote is now the presentation software of choice!). The theme of the day was prehospital care and major incidents.

The golden nuggets to take away include: (too many to list all of course)

• ‘Pull’ is the key to rapid extrication from cars if time critical from the Norweigan perspective. Dr Lars Wik of the Norweigen air ambulance presented their method of rapid extrication. Essentially they drag the car back on the road or away from what ever it has crashed into to control the environment and make space (360 style). They put a paramedic in the car whilst this is happening. They then make a cut in the A post near the roof, secure the rear of the car to a fire truck or fixed object with a chain and put another chain around the lower A post and steering wheel that is then winched tight. This has the effect of ‘reversing’ the crash and a few videos showed really fast access to the patient. The car seems to peel open. As they train specifically for it, there doesn’t seem to be any safety problems so far and its much quicker than their old method. I guess it doesnt matter really how you organise a rapid extrication method as long as it is trained for and everyone is on the same page.

• Dr Bob Winter presented his thoughts on hangings – to date no survivor of a non-judicial hanging has had a C-spine injury, so why do we collar them? Also there seems no point in cooling them. All imaging and concern for these patients should be based on the significant soft tissue injury that can be caused around the neck.

• Drownings – if the patient is totally submerged probably reasonable to search for 30mins in water that is >6 degrees or 90mins if <6 degrees. After that it becomes a body recovery (unless there is an air pocket or some exceptional circumstance). Patients that have drowned should have early ventilatory support if they show any signs of resp distress.

• Drs Julian Thompson and Mark Byers reassured us on a variety of safety issues at major incidents. It seems the risk to rescuers from secondary bombs at scene is low. Very few terrorist attacks world wide, ever, have had secondary devices so rescuers should be reassured (a bit). Greatest risk to the rescuer, like always, are the silly simple things that are a risk every day, like tripping over your own feet! With reference to chemical incidents, simple PPE seems to be sufficient for the vast majority of incidents, even fairly significant chemical ones, all this mucking about in full air tight suits is probably pointless and means patients cant be treated (at all). This led to the debate of how much risk should we, as rescue staff, accept? Clearly there are no absolute answers but minimising all risk to the rescuer is often at conflict with your ability to rescue. Where the balance should lie is a matter for organisations and individuals I guess.

• Sir Prof Keith Porter also gave us an update on the future of Prehospital emergency medicine as a recognised medical specialty. As those in the know, know, the specialty has been recognised by the GMC and the first draft of trainees are currently in post. More deaneries will be following suit soon to begin training but it is likely to take some time to build up large numbers of trained specialists. Importantly for those of us who already have completed our training there will be an option to sub specialise in PHEM but it will involve undertaking the FIMC exam. Great, more exams – see you there.

Day 3 – Major trauma
The focus of day 3 was that of damage control. Damage control surgery and damage control resucitation. We had indepth discussions about how to manage pelvic trauma and some of the finer points of trauma resuscitation.

Specific points raised were:

• Pelvic binders are great and can replace an ex fix if the abdomen needs opening to fix a spleen for example.

• You can catheterise patients with pelvic fractures (one gentle try).

• Most pelvic bleeds are venous which is why surgeons who can pack a pelvis is better than a radiologist who can mainly only treat arterial bleeds.

• Coagulopathy in trauma is not DIC and is probably caused by peripheral hypoperfusion.

• All the standard clotting tests that we use (INR etc) are useless and take too long to do. ROTEM or TEG is much better but still not perfect.

Also, as I am sure will please many – pressure isn’t flow so dont use pressors in trauma!

Chris Hill is an emergency and prehospital care physician based in the United Kingdom

Notes from Day 1 of the London Trauma Conference
I’ve always fancied trying my hand at journalism so when this opportunity to cover the London Trauma Conference (LTC) presented itself how could I resist? The LTC is well established now running into its sixth year. So what little gems does it have left to offer?

The Air Ambulance Symposium opened the conference with strong representation from Norway.

Dr Marius Rehn presented a thought provoking talk on pre-hospital trauma triage. Pragmatically there will always be a proportion of patients that are mistriaged. So is under triage worse than over triage? It depends on whose point of view you take. If you’re the trauma victim then under triage is your greatest fear. But as clinicians we display loyalty bias (preferential consideration for our current patient over those we have no involvement with) which leads to over triage. The consequences are usually unseen as they manifest in other areas of the health system – studies have demonstrated a detrimental effect in cardiac patients arriving in units where a trauma patient is treated concurrently. Commonly under triaged are older patients that have low mechanism falls and children involved in RTC’s are over triaged. Triage protocols aren’t perfect but those based on physiology and anatomy are the best; even better still an experienced clinician (physicians better than paramedics) and in the future we should think about using lactate clearance.

I have never needed any convincing that ultrasound has a role in pre-hospital care. However Dr Nils Petter Oveland presented some of his research (due for publication next year) which reinforces this belief. He studied chest ultrasound for the detection of pneumothoraces. Plain radiography interpreted by a consultant radiologist can detect a 500ml pneumothorax; ultrasonography can detect a mere 50ml. Using pig models he demonstrated a linear relationship between the volume of the pneumothorax and the sternal – lung point distance (lung point = where the lung edge remains in contact with the pleura). Practically how can we use this? A small pneumothorax may be detected by ultrasound but have no clinical consequence. Prior to aero medical transfer the lung point can be marked and if clinical deterioration occurs en route repeat US can accurately determine an increase in pneumothorax volume and guide treatment. Genius!

Prof Hans Morten Lossius provided a convincing argument for pre-hospital stroke thrombolysis. If you believe in this treatment, then it is more efficacious the sooner it is delivered (see photo). So why are we aiming for a thrombolysis time that is suboptimal? The thrombolysis times for a central Norwegian hospital were in the region of 3.5hrs, this reduced to 2.5hrs with rapid transportation. Approaching the problem from a different angle they trialled pre-hospital management with a mobile unit (CT scanner + neuroradiologist + neurologist) reducing time to thrombolysis to 72min (Lancet Neurology 2012, Walter). The next step is a multicentre RCT comparing standard treatment against a mobile CT + pre-hospital team with telemedical links to the Stroke centre……..

The Keynote address from Dr Gareth Davies took a look at the past and then a look to the future – the focus remained the same; providing the intervention patients need when they need it! Could this lead us into a future of Resuscitative Emergency Balloon Occlusion of the Aorta (REBOA) or Emergency Preservation Resuscitation (EPR) or emergency pre-hospital burr holes? Only time will tell.

Dr Steven Solid presented a double bill on patient safety. Admission to hospital is a high risk activity (as risky as bungee jumping!). Patient harm in aviation occurs 2 per 1000 flights. Only 25% were aviation related; mostly they are communication or equipment failures. He suggests medical line checks and team simulation training.

Dr Anne Weaver finished the first day with the story of her quest to get pre-hospital blood onto London HEMS to compliment the pre-hospital haemostatic resuscitation strategy they have for exsanguinating haemorrhage (tranexamic acid, prothrombin complex concentrate (for rapid warfarin reversal), POC INR machine, Buddy Lite™ blood warmers). Initial observations after the first six months are that ROSC is achieved more frequently in traumatic cardiac arrests although it’s too early to comment on mortality benefit. But this isn’t then end of the story – the next challenge is fresh frozen plasma.

I was taught a useful principle by a paediatric anaesthetist 10 years ago which has proven true in my experience and has contributed to keeping me calm when intubating sick kids. Unlike adults, in whom difficulty in intubation can often be unexpected, the vast majority of normal looking children are easy to intubate, and the ones who are difficult usually have obvious indicators such as dysmorphism.

This appears to be supported by recent evidence: in a large retrospective series of 11.219 anaesthesia patients, the overall incidence of difficult laryngoscopy [Cormack and Lehane (CML) grade III and IV] was only 1.35%, although was much higher in infants less than one year compared with older children. This low percentage is in the same ball park as two other paediatric studies. Besides younger age, their database suggested underweight, ASA III and IV physical status and, if obtainable, Mallampati III and IV findings as predictors for difficult laryngoscopy. The authors point out:

“…the oromaxillofacial surgery department with a high proportion of cleft palate interventions and pediatric cardiac surgery contributed substantially to the total number of difficult laryngoscopies. In patients undergoing pediatric cardiac surgery, a possible explanation for the higher incidence of CML III/IV findings might be that some congenital heart defects are associated with chromosomal anomalies like microdeletion 22q11.2 syndrome. This syndrome is also associated with extracardiac anomalies like cranio-facial dysmorphism“

Take home message: As a very rough rule of thumb to illustrate the difference between the ease/difficulty of laryngoscopy between adults and kids, I think it’s fair to say grade III or IV views occur in about 10% of adults but only about 1% of children.

Incidence and predictors of difficult laryngoscopy in 11.219 pediatric anesthesia procedures
Paediatr Anaesth. 2012 Aug;22(8):729-36
Click for abstract

Ever had to do a surgical airway in a child? Thought not. They’re pretty rare. Bill Heegaard MD from Henepin County Medical Center taught me a few approaches (with the help of an anaesthetised rabbit) which really got me thinking. It’s something I’d often trained for in my internal simulator, and I even keep the equipment for it in my house (listen out for an upcoming podcast on that). Research and experience has demonstrated that open surgical airway techniques are more reliable than transtracheal needle techniques in adults, but what about kids, in whom traditional teaching cautions against open techniques?

Australian investigators who were experienced airway proceduralists evaluated transtracheal needle techniques using a rabbit model (an excellent model for the infant airway). Their success rate was only 60% and they perforated the posterior tracheal wall in 42% of attempts. Of 13 attempts to insert a dedicated paediatric tracheotomy device, the Quicktrach Child, none were successful(1) (they did not use the Quicktrach Infant model as it is not available in Australia).

Danish investigators used fresh piglet cadavers weighing around 8 kg to assess two transtracheal cannulas, in which they achieved success rates of 65.6% and 68.8%(2). There was also a very high rate of posterior tracheal wall perforation. Using an open surgical tracheostomy technique, they were successful in 97% of attempts. These were also experienced operators, with a median anaesthetic experience of 12.5 years.

Their tracheotomy technique was nice and simple, and used just a scalpel, scissors, and surgical towel clips. Here’s their technique:

Simple tracheotomy procedure described by Holm-Knudsen et al

1. Identify larynx and proximal trachea by palpation
2. Vertical incision through the skin and subcutaneous tissue from the upper part of larynx to the sternal notch
3. Grasp strap muscles with two towel forceps and separate in the midline
4. Palpate and identify the trachea (palpate rather than look for tracheal rings, as in a live patient one would expect bleeding to obscure the view)
5. Stabilise the trachea by grasping it with a towel forceps
6. Insert sharp tip of the scissors between two tracheal rings and lift the trachea anteriorly to avoid damage to the posterior wall
7. Cut vertically in the midline of the trachea with the scissors – they chose to use the scissors to cut the tracheal rings to facilitate tube insertion
8. Insert the tracheal tube

Using ultrasound and CT to evaluate comparative airway dimensions, the authors concluded that the pig model is most useful for training emergency airway management in older children aged 5–10 years.

Why were they doing a tracheotomy rather than a cricothyroidotomy? Reasons given by the authors include:

• The infant cricothyroid membrane is very small
• Palpation of the thyroid notch may be hindered by the overlying hyoid bone
• The mandible may obstruct needle access to the cricothyroid membrane given the cephalad position in the neck of the infant larynx.

From an emergency medicine point of view, there are a couple of other reasons why we need to be able to access the trachea lower than the cricothyroid membrane. One is fractured larynx or other blunt or penetrating airway injury where there may be anatomical disruption at the cricothyroid level. The other situation is foreign body airway obstruction, when objects may lodge at the level of the cricoid ring which is functionally the narrowest part of the pediatric upper airway. Of course, alternative methods might be considered to remove the foreign body prior to tracheotomy, such as employing basic choking algorithms, and other techniques depending on whether you do or don’t have equipment.

Take home messages

• Transtracheal airways in kids are so rare, we can’t avoid extrapolating animal data

• Whichever infant or paediatric model is used, transtracheal needle techniques have a high rate of failure even by ‘experienced’ operators

• The small size and easy compressibility of the airway probably contributes to this failure rate, including the high rate of posterior wall puncture

• In keeping with adult audit data, open surgical techniques may have a higher success rate

• Tracheotomy may be necessary rather than cricothyroidotomy in infants and children depending on clinical scenario and accessibility of anatomy

• The stress and blood that is not simulated in cadaveric animal models will make open tracheotomy harder in a live patient, and so these success rates may not translate. However these factors do mean that whatever technique is used must be kept simple and should employ readily available and familiar equipment

• Something to maintain control and anterior position of the anterior trachea wall should be used during incision and intubation of the trachea. The study reported here used towel clips; sutures around the tracheal rings may also be used (see image below)

Sutures to stabilise trachea during infant tracheotomy simulation using a rabbit model

I recommend you add ‘paediatric tracheotomy’ to the list of procedures you might need to do (if it’s not already there). Identify what equipment you would use and run the simulation in your head and in your work environment.

Have fun.

2. Emergency airway access in children – transtracheal cannulas and tracheotomy assessed in a porcine model
Paediatr Anaesth. 2012 Dec;22(12):1159-65
Click for abstract

Want to access the femoral vein? Externally rotate the leg at the hip and things might be a bit easier. This study was done in adult patients, with the knee straight and no abduction applied. External rotation is also helpful in kids, with abduction up to sixty degrees.

Objective: To determine if external rotation of the leg increases the size and accessibility of the femoral vein compared with a neutral position.

Methods: One hundred patients presenting to a tertiary teaching hospital were prospectively recruited. The right common femoral vein of each subject was scanned with a linear probe (5–10 MHz) inferior to the inguinal ligament, with the leg in a neutral position and then in the externally rotated position. The transverse diameter of the femoral vein, the accessible diameter of the vein (lying medial to the femoral artery) and the depth of the vein were measured.

Results: The mean diameter of the femoral vein in the externally rotated leg was greater than with the leg in the neutral position (15.4 mm vs 13.8 mm); the mean difference was 1.6 mm (95% CI 1.3–1.9). The mean accessible diameter of the femoral vein was larger with the leg externally rotated (13.8 mm vs 11.7 mm, mean difference 2.1 mm, 95% CI 1.8–2.5). The depth from the skin to the femoral vein was less with the leg in external rotation (20.9 mm vs 22.6 mm, mean difference 1.7 mm, 95% CI 1.2–2.2). The mean diameter and depth were greater in patients with overweight or obese body mass index (BMI) measurements in both leg positions. The increase in femoral vein diameter and accessibility with external rotation was observed in all BMI groups.

Conclusion: The total and accessible femoral vein diameter is increased and the surface depth of the vein is decreased by placing the leg in external rotation compared with the neutral position.

Simple external rotation of the leg increases the size and accessibility of the femoral vein
Emerg Med Australas. 2012 Aug;24(4):408-13

I like this paper for introducing a new concept to me. For years the critical care community has recognised the link between hyperglycaemia and mortality, leading to early recommendations of intensive insulin regimens subsequently shown not to be of benefit. Now it appears that the association between hyperglycaemia and mortality may be less relevant in patients with a normal lactate.

In a study of adult nondiabetic critically ill patients, hyperglycaemia had a significant association with increased mortality risk using simple univariate analysis. When they adjusted for concurrent hyperlactataemia however, hyperglycaemia was not significantly associated with increased mortality risk.

The authors discuss several known or postulated aspects of interplay between lactate and glucose in sepsis:

• Hyperlactataemia appears to inhibit glucose uptake by muscle cells and decrease activity of the GLUT-4 transporters

• Hyperlactataemia has also been shown to increase insulin resistance directly

• Glucose and lactate levels tend to be elevated simultaneously in severe sepsis at baseline.

• Experimentally it has been estimated that 45% of infused (radiolabelled) lactate is either converted into glucose via gluconeogenesis or is transformed into glycogen via the Cori cycle, representing a higher proportion of glucose formation from lactate than in nonseptic controls.

• It is possible that elevated glucose and lactate levels in sepsis both may be measures of the same phenomenon: glucose accumulates due to the sympathomimetic response to a systemic infection with increased catecholamine levels leading to increased activity of the Na+K+-ATPase, resulting in accumulation of adenosine diphosphate (ADP). Increased levels of ADP in turn augment glycogenolysis.

• Mitochondrial metabolism cannot meet the increased cellular energy needs of sepsis, resulting in accumulation of ADP and leading to cytosolic glycolysis and lactate production, even in an aerobic environment.

The augmented glycolysis of sepsis (and during adrenergic therapy such as epinephrine/adrenaline or albuterol/salbutamol) is one of the causes of a raised lactate to consider when applying the LACTATES mnemonic I like to use.

Hyperlactatemia affects the association of hyperglycemia with mortality in nondiabetic adults with sepsis
Acad Emerg Med. 2012 Nov;19(11):1268-75
Click for abstract

A meta-analysis of studies evaluation transthoracic echo as a means of predicting return of spontaneous circulation in cardiac arrest (ROSC) provides some likelihood ratios to what we already know: absence of sonographic cardiac activity means a very low chance of ROSC.

The authors report a pooled negative LR of 0.18 (95% CI = 0.10 to 0.31), and a positive likelihood ratio of 4.26 (95% CI = 2.63 to 6.92).

They conclude that focused transthoracic echo is a fairly effective (although not definitive) test for predicting death if no cardiac activity is noted during resuscitation, and recommend interpreting the echo in the light of the test characteristics and the clinical pre-test probability, as one should do for all imaging investigations:

“An elderly patient with an unwitnessed cardiac arrest already has very poor odds for survival. Confirmation of asystole on echo lowers those pretest odds by a factor of 5.6 and therefore might lead to termination of resuscitation. However, in the case of a 50-year-old rescued from drowning, detection of cardiac contractility on echo would increase his already fair odds of survival by a factor of 4.3, prompting continued aggressive resuscitation.”

Only five relatively small studies contributed to the findings. A more definitive answer to this question should be provided in the future by the multi-centre REASON 1 trial.

Objectives:  The objective was to determine if focused transthoracic echocardiography (echo) can be used during resuscitation to predict the outcome of cardiac arrest.

Methods:  A literature search of diagnostic accuracy studies was conducted using MEDLINE via PubMed, EMBASE, CINAHL, and Cochrane Library databases. A hand search of references was performed and experts in the field were contacted. Studies were included for further appraisal and analysis only if the selection criteria and reference standards were met. The eligible studies were appraised and scored by two independent reviewers using a modified quality assessment tool for diagnostic accuracy studies (QUADAS) to select the papers included in the meta-analysis.

Results:  The initial search returned 2,538 unique papers, 11 of which were determined to be relevant after screening criteria were applied by two independent researchers. One additional study was identified after the initial search, totaling 12 studies to be included in our final analysis. The total number of patients in these studies was 568, all of whom had echo during resuscitation efforts to determine the presence or absence of kinetic cardiac activity and were followed up to determine return of spontaneous circulation (ROSC). Meta-analysis of the data showed that as a predictor of ROSC during cardiac arrest, echo had a pooled sensitivity of 91.6% (95% confidence interval [CI] = 84.6% to 96.1%), and specificity was 80.0% (95% CI = 76.1% to 83.6%). The positive likelihood ratio for ROSC was 4.26 (95% CI = 2.63 to 6.92), and negative likelihood ratio was 0.18 (95% CI = 0.10 to 0.31). Heterogeneity of the results (sensitivity) was nonsignificant (Cochran’s Q: χ(2) = 10.63, p = 0.16, and I(2) = 34.1%).

Conclusions:  Echocardiography performed during cardiac arrest that demonstrates an absence of cardiac activity harbors a significantly lower (but not zero) likelihood that a patient will experience ROSC. In selected patients with a higher likelihood of survival from cardiac arrest at presentation, based on established predictors of survival, echo should not be the sole basis for the decision to cease resuscitative efforts. Echo should continue to be used only as an adjunct to clinical assessment in predicting the outcome of resuscitation for cardiac arrest.

Bedside Focused Echocardiography as Predictor of Survival in Cardiac Arrest Patients: A Systematic Review
Acad Emerg Med. 2012 Oct;19(10):1119-1126

The chaps from the Emergency Medical Retrieval Service in the UK compared invasive (IABP) and non-invasive blood pressure (NIBP) measurements on the ground and in the air. They concluded that NIBP was unreliable, although it was no worse in the aeromedical environment than in the hospital. Not surprisingly there was a better correlation between the mean IABP and NIBP than systolic or diastolic pressures (oscillometric NIBP devices measure the mean BP and derive systolic and diastolic using an algorithm specific to the device).

In their summary, they recommend:

• IABP monitoring should be used in any unwell patient in whom accurate blood pressure measurement is desirable.
• The aeromedical transport environment does not lead to less precise NIBP results than the non-transport environment.
• Where NIBP measurement is the only option, the mean blood pressure should be used in preference to systolic measurements

Blood pressure measurement is an essential physiological measurement for all critically ill patients. Previous work has shown that non-invasive blood pressure is not an accurate reflection of invasive blood pressure measurement. In a transport environment, the effects of motion and vibration may make non-invasive blood pressure less accurate.

Consecutive critically ill patients transported by a dedicated aeromedical retrieval and critical care transfer service with simultaneous invasive and non-invasive blood pressure measurements were analysed. Two sets of measurements were recorded, first in a hospital environment before departure (pre-flight) and a second during aeromedical transport (in-flight).

A total of 56 complete sets of data were analysed. Bland-Altman plots showed limits of agreement (precision) for pre-flight systolic blood pressure were -37.3 mmHg to 30.0 mmHg, and for pre-flight mean arterial pressure -20.5 mmHg to 25.0 mmHg. The limits of agreement for in-flight systolic blood pressure were -40.6 mmHg to 33.1 mmHg, while those for in-flight mean blood pressure in-flight were -23.6 mmHg to 24.6 mmHg. The bias for the four conditions ranged from 0.5 to -3.8 mmHg. There were no significant differences in values between pre-flight and in-flight blood pressure measurements for all categories of blood pressure measurement.

Thus, our data show that non-invasive blood pressure is not a precise reflection of invasive intra-arterial blood pressure. Mean blood pressure measured non-invasively may be a better marker of invasive blood pressure than systolic blood pressure. Our data show no evidence of non-invasive blood pressures being less accurate in an aeromedical transport environment.

Comparison of non-invasive and invasive blood pressure in aeromedical care
Anaesthesia. 2012 Dec;67(12):1343-7

A meta-analysis attempts to quantify etomidate’s effect on mortality and adrenal suppression. Of course, we all know a meta-analysis can only be as reliable as the original data it’s analysing. I think editorialists Lauzier and Turgeon have a point with their statement:

“Given the widespread use of etomidate in the emergency room, we believe that a RCT designed to evaluate the safety of etomidate as a hypnotic agent for endotracheal intubation of patients with sepsis is not only ethical but also urgently warranted”

For a critique of the paper and subsequent discussion, check out the Academic Life in EM blog post by Brian Hayes

OBJECTIVE: To evaluate the effects of single-dose etomidate on the adrenal axis and mortality in patients with severe sepsis and septic shock.

DESIGN: A systematic review of randomized controlled trials and observational studies with meta-analysis.

SETTING: Literature search of EMBASE, Medline, Cochrane Database, and Evidence-Based Medical Reviews.

SUBJECTS: Sepsis patients who received etomidate for rapid sequence intubation.

INTERVENTIONS: None.

MEASUREMENTS AND MAIN RESULTS: We conducted a systematic review of randomized controlled trials and observational studies with meta-analysis assessing the effects of etomidate on adrenal insufficiency and all-cause mortality published between January 1950 and February 2012. We only examined studies including septic patients. All-cause mortality served as our primary end point, whereas the prevalence of adrenal insufficiency was our secondary end point. Adrenal insufficiency was determined using a cosyntropin stimulation test in all studies. We used a random effects model for analysis; heterogeneity was assessed with the I statistic. Publication bias was evaluated with Begg’s test. Five studies were identified that assessed mortality in those who received etomidate. A total of 865 subjects were included. Subjects who received etomidate were more likely to die (pooled relative risk 1.20; 95% confidence interval 1.02-1.42; Q statistic, 4.20; I2 statistic, 4.9%). Seven studies addressed the development of adrenal suppression associated with the administration of etomidate; 1,303 subjects were included. Etomidate administration increased the likelihood of developing adrenal insufficiency (pooled relative risk 1.33; 95% confidence interval 1.22-1.46; Q statistic, 10.7; I2 statistic, 43.9%).

CONCLUSIONS: Administration of etomidate for rapid sequence intubation is associated with higher rates of adrenal insufficiency and mortality in patients with sepsis.

Etomidate is associated with mortality and adrenal insufficiency in sepsis: A meta-analysis Crit Care Med. 2012 Nov;40(11):2945-53

The Eastern Association for the Surgery of Trauma has published a number of helpful evidence-based guidelines for trauma management, and many of them are included in this month’s Journal of Trauma and Acute Care Surgery

Here are brief snippets from some of them. All the guidelines can be viewed or downloaded in full for free here.

Nonoperative management of blunt hepatic injury

• Nonoperative management of blunt hepatic injuries currently is the treatment modality of choice in hemodynamically stable patients, irrespective of the grade of injury or patient age.

• Patients presenting with hemodynamic instability and peritonitis still warrant emergent operative intervention.

• Intravenous contrast enhanced computed tomographic scan is the diagnostic modality of choice for evaluating blunt hepatic injuries.

Selective nonoperative management of blunt splenic injury

• Nonoperative management of blunt splenic injuries is now the treatment modality of choice in hemodynamically stable patients, irrespective of the grade of injury, patient age, or the presence of associated injuries.

• Patients presenting with hemodynamic instability and peritonitis still warrant emergent operative intervention.

• Intravenous contrast enhanced computed tomographic scan is the diagnostic modality of choice for evaluating blunt splenic injuries.

Screening for blunt cardiac injury

• Electrocardiogram (ECG) alone is not sufficient to rule out BCI.

• BCI can be ruled out only if both ECG result and troponin I level are normal, a significant change from the previous guideline.

• Patients with new ECG changes and/or elevated troponin I should be admitted for monitoring.

• Echocardiogram is not beneficial as a screening tool for BCI and should be reserved for patients with hypotension and/or arrhythmias.

• The presence of a sternal fracture alone does not predict BCI.

• Cardiac computed tomography or magnetic resonance imaging can be used to differentiate acute myocardial infarction from BCI in trauma patients.

Evaluation and management of penetrating lower extremity arterial trauma

• Expedited triage of patients is possible with physical examination and/or the measurement of ankle-brachial indices.

• Computed tomographic angiography has become the diagnostic study of choice when imaging is required.

• Tourniquets and intravascular shunts have emerged as adjuncts in the treatment of penetrating lower extremity arterial trauma.

Prophylactic antibiotic use in penetrating abdominal trauma

• There is evidence to support a Level I recommendation that prophylactic antibiotics should only be administered for 24 hours in the presence of a hollow viscus injury.

• There are no data to support continuing prophylactic antibiotics longer than 24 hours in damage control laparotomy.

Screening for thoracolumbar spinal injuries in blunt trauma

• Multidetector computed tomographic scans have become the screening modality of choice and the criterion standard in screening for TLS injuries.

• Patients without altered mentation or significant mechanism may be excluded by clinical examination without imaging.

• Patients with gross neurologic deficits or concerning clinical examination findings with negative imaging should receive a magnetic resonance imaging expediently, and the spine service should be consulted

Emergency tracheal intubation immediately following traumatic injury

• The decision to intubate a patient following traumatic injury is based on multiple factors, including the need for oxygenation and ventilation, the extent and mechanism of injury, predicted operative need, or progression of disease.

• Rapid sequence intubation with direct laryngoscopy continues to be the recommended method for ETI, although the use of airway adjuncts such as blind insertion supraglottic devices and video laryngoscopy may be useful in facilitating successful ETI and may be preferred in certain patient populations.

• There is no pharmacologic induction agent of choice for ETI; however, succinylcholine is the neuromuscular blockade agent recommended for rapid sequence intubation.

Presumptive antibiotic use in tube thoracostomy for traumatic hemopneumothorax

• Routine presumptive antibiotic use to reduce the incidence of empyema and pneumonia in TT for traumatic hemopneumothorax is controversial; however, there is insufficient published evidence to support any recommendation either for or against this practice.

Evaluation and management of geriatric trauma

• Effective evidence-based care of aging patients necessitates aggressive triage, correction of coagulopathy, and limitation of care when clinical evidence points toward an overwhelming likelihood of poor long-term prognosis

Management of pulmonary contusion and flail chest

• Patients with PC-FC should not be excessively fluid restricted but should be resuscitated to maintain signs of adequate tissue perfusion.

• Obligatory mechanical ventilation in the absence of respiratory failure should be avoided.

• The use of optimal analgesia and aggressive chest physiotherapy should be applied to minimize the likelihood of respiratory failure.

• Epidural catheter is the preferred mode of analgesia delivery in severe flail chest injury.

• Paravertebral analgesia may be equivalent to epidural analgesia and may be appropriate in certain situations when epidural is contraindicated.

• A trial of mask continuous positive airway pressure should be considered in alert patients with marginal respiratory status.

• Patients requiring mechanical ventilation should be supported in a manner based on institutional and physician preference and separated from the ventilator at the earliest possible time.

• Positive end-expiratory pressure or continuous positive airway pressure should be provided.

• High-frequency oscillatory ventilation should be considered for patients failing conventional ventilatory modes. Independent lung ventilation may also be considered in severe unilateral pulmonary contusion when shunt cannot be otherwise corrected.

• Surgical fixation of flail chest may be considered in cases of severe flail chest failing to wean from the ventilator or when thoracotomy is required for other reasons.

• Self-activating multidisciplinary protocols for the treatment of chest wall injuries may improve outcome and should be considered where feasible.

• Steroids should not be used in the therapy of pulmonary contusion.

• Diuretics may be used in the setting of hydrostatic fluid overload in hemodynamically stable patients or in the setting of known concurrent congestive heart failure.

Evaluation and management of small-bowel obstruction

• Level I evidence now exists to recommend the use of computed tomographic scan, especially multidetector computed tomography with multiplanar reconstructions, in the evaluation of patients with SBO because it can provide incremental clinically relevant information over plains films that may lead to changes in management.

• Patients with evidence of generalized peritonitis, other evidence of clinical deterioration, such as fever, leukocytosis, tachycardia, metabolic acidosis, and continuous pain, or patients with evidence of ischemia on imaging should undergo timely exploration.

• The remainder of patients can safely undergo initial nonoperative management for both partial and complete SBO.

• Water-soluble contrast studies should be considered in patients who do not clinically resolve after 48 to 72 hours for both diagnostic and potential therapeutic purposes.

• Laparoscopic treatment of SBO has been demonstrated to be a viable alternative to laparotomy in selected cases.

2012 Eastern Association for the Surgery of Trauma (EAST) Practice Management Guidelines Supplement
J Trauma Acute Care Surg. 2012 Nov;73(5 Suppl 4)

A pet topic that keeps coming up here is management of tension pneumothorax. Plenty of studies demonstrate that traditionally taught needle thoracostomy may fail, and open, or ‘finger’ thoracostomy is recommended for the emergency management of tension pneumothorax in a patient who is being ventilated with positive pressure (including those patients in cardiac arrest).

A recent CT scan-based study of adult trauma patients makes the case that needle decompression with a standard iv cannula would be expected to fail in 42.5% of cases at the second intercostal space (ICS) compared with 16.7% at the fifth ICS at the anterior axillary line (AAL).

The authors add an important point: “As BMI increases, there is a stepwise increase in chest wall thickness, further compounding the difficulty of needle placement in all but the lowest BMI quartile for the second ICS.”

An accompanying editorial cautions that the proximity of the heart may confer a safety issue if a needle is inserted blindly into the left 5th ICS at the AAL.

Objective To compare the distance to be traversed during needle thoracostomy decompression performed at the second intercostal space (ICS) in the midclavicular line (MCL) with the fifth ICS in the anterior axillary line (AAL).

Design Patients were separated into body mass index (BMI) quartiles, with BMI calculated as weight in kilograms divided by height in meters squared. From each BMI quartile, 30 patients were randomly chosen for inclusion in the study on the basis of a priori power analysis (n = 120). Chest wall thickness on computed tomography at the second ICS in the MCL was compared with the fifth ICS in the AAL on both the right and left sides through all BMI quartiles.

Setting Level I trauma center.

Patients Injured patients aged 16 years or older evaluated from January 1, 2009, to January 1, 2010, undergoing computed tomography of the chest.

Results A total of 680 patients met the study inclusion criteria (81.5% were male and mean age was 41 years [range, 16-97 years]). Of the injuries sustained, 13.2% were penetrating, mean (SD) Injury Severity Score was 15.5 (10.3), and mean BMI was 27.9 (5.9) (range, 15.4-60.7). The mean difference in chest wall thickness between the second ICS at the MCL and the fifth ICS at the AAL was 12.9 mm (95% CI, 11.0-14.8; P < .001) on the right and 13.4 mm (95% CI, 11.4-15.3; P < .001) on the left. There was a stepwise increase in chest wall thickness across all BMI quartiles at each location of measurement. There was a significant difference in chest wall thickness between the second ICS at the MCL and the fifth ICS at the AAL in all quartiles on both the right and the left. The percentage of patients with chest wall thickness greater than the standard 5-cm decompression needle was 42.5% at the second ICS in the MCL and only 16.7% at the fifth ICS in the AAL.

Conclusions In this computed tomography–based analysis of chest wall thickness, needle thoracostomy decompression would be expected to fail in 42.5% of cases at the second ICS in the MCL compared with 16.7% at the fifth ICS in the AAL. The chest wall thickness at the fifth ICS AAL was 1.3 cm thinner on average and may be a preferred location for needle thoracostomy decompression.

Radiologic evaluation of alternative sites for needle decompression of tension pneumothorax
Arch Surg. 2012 Sep 1;147(9):813-8

In what the authors describe as ‘the largest and most rigorous description of blunt thoracoabdominal injury to date’, we learn some interesting things and are reminded of some others:

Most solid organ injuries in the abdomen are managed non-operatively

Thoracotomy – especially non-resuscitative thoracotomy – is rare

In patients with thoracoabdominal trauma, the overwhelming majority of injuries requiring operative intervention were found in the abdomen, therefore..

…excluding those patients in extremis requiring a resuscitative thoracotomy, the initial incision, without directive radiological information, belongs in the abdomen

Concomitant thoracic injury did not preclude nonoperative management of abdominal solid organ injury

This is a really interesting paper providing important data on the outcomes and management of a patient group that frequently produces management dilemmas in trauma centres.

The double jeopardy of blunt thoracoabdominal trauma
Arch Surg. 2012 Jun;147(6):498-504
Click for abstract

A ‘lung protective’ ventilation strategy that includes low tidal volumes has been shown to improve outcomes in patients with ARDS. Many also advocate it as sensible practice for any ventilated patient as a means of minimising the chances of ventilator-induced lung injury and hopefully improving outcome. A recent meta-analysis provides further evidence to support that recommendation:

Context Lung-protective mechanical ventilation with the use of lower tidal volumes has been found to improve outcomes of patients with acute respiratory distress syndrome (ARDS). It has been suggested that use of lower tidal volumes also benefits patients who do not have ARDS.

Objective To determine whether use of lower tidal volumes is associated with improved outcomes of patients receiving ventilation who do not have ARDS.

Data Sources MEDLINE, CINAHL, Web of Science, and Cochrane Central Register of Controlled Trials up to August 2012.

Study Selection Eligible studies evaluated use of lower vs higher tidal volumes in patients without ARDS at onset of mechanical ventilation and reported lung injury development, overall mortality, pulmonary infection, atelectasis, and biochemical alterations.

Data Extraction Three reviewers extracted data on study characteristics, methods, and outcomes. Disagreement was resolved by consensus.

Data Synthesis Twenty articles (2822 participants) were included. Meta-analysis using a fixed-effects model showed a decrease in lung injury development (risk ratio [RR], 0.33; 95% CI, 0.23 to 0.47; I2, 0%; number needed to treat [NNT], 11), and mortality (RR, 0.64; 95% CI, 0.46 to 0.89; I2, 0%; NNT, 23) in patients receiving ventilation with lower tidal volumes. The results of lung injury development were similar when stratified by the type of study (randomized vs nonrandomized) and were significant only in randomized trials for pulmonary infection and only in nonrandomized trials for mortality. Meta-analysis using a random-effects model showed, in protective ventilation groups, a lower incidence of pulmonary infection (RR, 0.45; 95% CI, 0.22 to 0.92; I2, 32%; NNT, 26), lower mean (SD) hospital length of stay (6.91 [2.36] vs 8.87 [2.93] days, respectively; standardized mean difference [SMD], 0.51; 95% CI, 0.20 to 0.82; I2, 75%), higher mean (SD) PaCO2 levels (41.05 [3.79] vs 37.90 [4.19] mm Hg, respectively; SMD, −0.51; 95% CI, −0.70 to −0.32; I2, 54%), and lower mean (SD) pH values (7.37 [0.03] vs 7.40 [0.04], respectively; SMD, 1.16; 95% CI, 0.31 to 2.02; I2, 96%) but similar mean (SD) ratios of PaO2 to fraction of inspired oxygen (304.40 [65.7] vs 312.97 [68.13], respectively; SMD, 0.11; 95% CI, −0.06 to 0.27; I2, 60%). Tidal volume gradients between the 2 groups did not influence significantly the final results.

Conclusions Among patients without ARDS, protective ventilation with lower tidal volumes was associated with better clinical outcomes. Some of the limitations of the meta-analysis were the mixed setting of mechanical ventilation (intensive care unit or operating room) and the duration of mechanical ventilation.

Association Between Use of Lung-Protective Ventilation With Lower Tidal Volumes and Clinical Outcomes Among Patients Without Acute Respiratory Distress Syndrome – A Meta-analysis
JAMA. 2012;308(16):1651-1659

Inpatient paediatric teams can be scornful when bronchodilators are given by ED staff to wheezing infants, correctly referring to the lack of evidence of clinical benefit(1). There is however a persisting meme out there I’ve heard on a number of occasions that ‘young infants don’t have the receptors so inhaled beta agonists will never work.’ I’d love to know where this comes from.

Apparently, beta 2-receptors are present from the 16th gestational week(2). Pulmonary function testing of ventilated, very-low-birth-weight babies has shown that some consistently responded to beta-agonists whereas others did not(3). A newly published study reports that a quarter of mechanically ventilated infants with bronchiolitis were responders to inhaled albuterol, defined as a reduction in respiratory system resistance more than 30% below baseline(4).

In summary: beta-agonist bronchodilators have not been shown to improve clinical outcomes in wheezing infants. However some infants with some wheezing disorders will show a response in terms of pulmonary function. The receptors are there, and in life-threatening presentations bronchodilators should certainly be considered.

1. Short acting beta agonists for recurrent wheeze in children under 2 years of age
Cochrane Database Syst Rev. 2002;(3):CD002873
Click to read abstract

2. The beta-2-agonists in asthma in infants and young children
Arch Pediatr. 2002 Aug;9 Suppl 3:384s-389s
Click to read abstract

3. Use of a beta-agonist in ventilated, very-low-birth-weight babies: a longitudinal evaluation
Dev Pharmacol Ther. 1990;15(2):61-7
Click to read abstract

4. Pulmonary mechanics following albuterol therapy in mechanically ventilated infants with bronchiolitis
J Asthma. 2012 Sep;49(7):688-96
Click to read abstract

Another nail in the coffin of starch solutions for critical care patients was banged in by Prof Myburgh and colleagues who published the results of the CHEST randomised trial this week(1). 7000 Australasian ICU patients received either 6% HES (130/0.4) in 0.9% saline (HES group) or 0.9% saline (saline group). There was no difference in mortality but there was more renal dysfunction, rash, and pruritis in the HES group.

This can be combined with another recent starch vs crystalloid paper demonstrating adverse outcomes from starch(2) to make the case that there is no role for these pharmaceuticals in resuscitation or critical care.

1. Hydroxyethyl Starch or Saline for Fluid Resuscitation in Intensive Care
N Engl J Med. 2012 Oct 17. [Epub ahead of print] Free Full Text
Click for abstract

2. Hydroxyethyl starch 130/0.42 versus Ringer’s acetate in severe sepsis
N Engl J Med. 2012 Jul 12;367(2):124-34
Click for abstract

Ever waste time trying to shake some ultrasound gel out the bottle, like a resistant blob of ketchup?
Sydney emergency medicine registrar Dr Steve Skinner demonstrates how to solve this. With physics.

This really does work, and has saved me a lot of time already. I now do a somewhat less ballistic version than the one demonstrated, so that patients don’t think I’m mad.

I continue to be bewildered at my ED colleagues’ overwhelming preference for 0.9% saline as a resuscitation fluid regardless of clinical presentation. However, I have to acknowledge a lack of robust high level clinical evidence demonstrating its relative harm compared with more balanced solutions such as Hartmann’s / Ringer’s lactate or one of the more scarcely available Plasma-Lyte solutions.

Human and animal studies have demonstrated that saline exacerbates hyperchloraemia and metabolic acidosis and has renal effects including renal vasoconstriction and decreased glomerular filtration rate. A large observational study on surgical patients suggested that saline therapy increases the risk of patients requiring acute dialysis compared with Plasma-Lyte administration(1).

A new study in JAMA provides some further clinical evidence that saline has harmful renal effects(2). It was a before-and-after observational study, in which the change was a restriction in chloride-rich fluids so that they were made available only after prescription by the attending specialist for specific conditions (eg, hyponatraemia, traumatic brain injury, and cerebral oedema). Four of the authors published another study on the metabolic effects of this changed fluid strategy, presumably on the same or an overlapping cohort of patients, which I blogged about here.

Significant findings were that the chloride-restrictive strategy was associated with a significantly lower increase in serum creatinine level during ICU stay, a decrease in the incidence of renal injury and failure (according to the RIFLE definitions), and a decrease in renal replacement therapy. These effects persisted after adjusting for known contributors to acute kidney injury.

As this is not a randomised trial cause and effect cannot be assumed, but this is consistent with other work.

In summary, keep pushing the saline if you want to increase your patients’ risk of acute kidney injury and the need for dialysis, whilst rendering them acidotic. You may even decrease their gut perfusion(3) and give them abdominal discomfort and subjective decreased cognitive ability(4). Alternatively, give Hartmann’s / Ringer’s lactate… although bear in mind that might not be such a good choice in the context of hyponatraemia, alkalaemia, cerebral oedema, or traumatic brain injury.

1. Major complications, mortality, and resource utilization after open abdominal surgery: 0.9% saline compared to Plasma-Lyte
Ann Surg. 2012 May;255(5):821-9
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2. Association Between a Chloride-Liberal vs Chloride-Restrictive Intravenous Fluid Administration Strategy and Kidney Injury in Critically Ill Adults
JAMA. 2012 Oct 17;308(15):1566-72
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3. The effects of balanced versus saline-based hetastarch and crystalloid solutions on acid-base and electrolyte status and gastric mucosal perfusion in elderly surgical patients
Anesth Analg. 2001 Oct;93(4):811-6
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4. The effect of intravenous lactated Ringer’s solution versus 0.9% sodium chloride solution on serum osmolality in human volunteers.
Anesth Analg. 1999 May;88(5):999-1003
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A study examining patterns of procalcitonin in a group of critically ill patients(1) showed some interesting findings:

Shock was associated with higher procalcitonin values independent of the presence of infection

Procalcitonin (PCT) levels were less in patients who developed infections later during their ICU stay compared with those who had infections when admitted to ICU.

The accompanying editorial(2) reminds us about commonly used inflammatory biomarkers.

White blood cells are influenced by almost every inflammatory stimulus, rendering them unhelpful in the management of severely ill patients.

Daily monitoring of CRP levels can identify ICU-acquired infections early, and some prognostic information can be provided by how rapidly CRP levels respond to treatment.

PCT rises early in severe sepsis, mainly by pneumonia and bloodstream infections, and can reflect the severity of the systemic inflammatory response syndrome to infection. PCT is more specific than CRP for infection compared with non-infectious causes of systemic inflammatory response syndrome. However PCT can also be increased in noninfectious diseases such as acute pancreatitis and cardiogenic shock.

1. Longitudinal changes in procalcitonin in a heterogenous group of critically ill patients
Crit Care Med. 2012 Oct;40(10):2781-2787
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2. The many facets of procalcitonin in the critically ill population
Crit Care Med. 2012 Oct;40(10):2903-5

During a Krav Maga self defence drill a middle aged martial arts enthusiast cleverly blocked a full contact punch with his nose. Following a suggestion to pause training to control the bleeding, he noticed some lateral nasal displacement which was easily manually reduced with an audible click. He was able to resume training with a piece of toilet paper stuffed up the bleeding nostril, and no ill effects were noticed on subsequent training nights that week.

The day after injury he demonstrated a characteristic bruising pattern:

As he was working an aeromedical retrieval shift, he was able to use the Retrieval Service Sonosite M-Turbo ultrasound machine to identify the cortical disruption from his nasal bone fracture.

Ultrasound compares favourably with both plain radiography(1) and computed tomography(2) in the diagnosis of nasal bone fractures.

Personal access to sonography and full board certification in emergency medicine help to decrease health care costs and emergency department load when individuals sustain fractures that do not require operative management(3).

1. Comparison of ultrasonography and conventional radiography in the diagnosis of nasal fractures.
Arch Otolaryngol Head Neck Surg. 2005 May;131(5):434-9

2. Comparison of high-resolution ultrasonography and computed tomography in the diagnosis of nasal fractures.
J Ultrasound Med. 2009 Jun;28(6):717-23

3. Only when I laugh
When the same bloke broke his rib

The Taiwanese are at it again with their extracorporeal life support. This time, they report their outcomes in children who received ECMO for in-hospital cardiac arrest. Interestingly, the patients with pure cardiac causes of cardiac arrest had a survival rate similar to patients with non-cardiac causes.

PURPOSE: The study aims to describe 11 years of experience with extracorporeal cardiopulmonary resuscitation (ECPR) for in-hospital paediatric cardiac arrest in a university affiliated tertiary care hospital.

METHODS: Paediatric patients who received extracorporeal membrane oxygenation (ECMO) during active extracorporeal cardiopulmonary resuscitation (ECPR) at our centre from 1999 to 2009 were included in this retrospective study. The results from three different cohorts (1999-2001, 2002-2005 and 2006-2009) were compared. Survival rates and neurological outcomes were analysed. Favourable neurological outcome was defined as paediatric cerebral performance categories (PCPC) 1, 2 and 3.

RESULTS: We identified 54 ECPR events. The survival rate to hospital discharge was 46% (25/54), and 21 (84%) of the survivors had favourable neurological outcomes. The duration of CPR was 39±17 min in the survivors and 52±45 min in the non-survivors (p=NS). The patients with pure cardiac causes of cardiac arrest had a survival rate similar to patients with non-cardiac causes (47% (18/38) vs. 44% (7/16), p=NS). The non-survivors had higher serum lactate levels prior to ECPR (13.4±6.4 vs. 8.8±5.1 mmol/L, p<0.01) and more renal failure after ECPR (66% (19/29) vs. 20% (5/25), p<0.01). The patients resuscitated between 2006 and 2009 had shorter durations of CPR (34±13 vs. 78±76 min, p=0.032) and higher rates of survival (55% (16/29) vs. 0% (0/8), p=0.017) than those resuscitated between 1999 and 2002.

CONCLUSIONS: In our single-centre experience with ECPR for paediatric in-hospital cardiac arrest, the duration of CPR has become shorter and outcomes have improved in recent years. Higher pre-ECPR lactate levels and the presence of post-ECPR renal failure were associated with increased mortality. The presence of non-cardiac causes of cardiac arrest did not preclude successful ECPR outcomes. The duration of CPR was not significantly associated with poor outcomes in this study.

Eleven years of experience with extracorporeal cardiopulmonary resuscitation for paediatric patients with in-hospital cardiac arrest
Resuscitation. 2012 Jun;83(6):710-4