Question 1
A 25 year old female presents to the emergency department with a history of right lower abdominal pain. Her LMP was 2 weeks previously and she is otherwise fit and well. She is on no regular medications and has no known allergies.

a. List your differential diagnosis for this woman's presentation:

The differential diagnosis must include;

• appendicitis
• ectopic pregnancy
• ovarian cyst
• ovarian torsion

Other considerations can include;

• pyelonephritis
• renal colic
• musculoskeletal UTI
• mittelschmirtz

b. What investigations would you order?

• FBC
• CRP
• EUC
• Urinalysis +/- microscopy
• Beta-HCG (urine and serum)
• Imaging - pelvic and lower abdominal USS
• Negative marking for CT as first imaging choice in a young woman

c. What is the emergency management for this woman?

• Vascular access
• Keep NBM
• Maintenance intravenous fluids (need to be specific as to fluid type and rate)
• Fluid resuscitation if hypotensive (crystalloid +/- blood products - need to be specific about targets and amounts of fluids given)
• Analgesia - must be a parenteral narcotic given in appropriate dosage.
• Consult - general surgery +/- O&G

Question 2
A 35 year old male presents to the emergency department with SOB. He has a history of asthma, and has audible wheeze on arrival to the ED.

a. What are the signs and symptoms of a patient with severe respiratory distress?

• inability to speak
• diaphoresis
• tripod positioning
• extreme tachypnoea (RR > 30)
• hypoxaemia (Pulse Ox < 90%)
• accesory muscle use, intercostal recession
• tracheal tug
• stridor
• silent chest on auscultation
• tachycardia or bradycardia
• pulsus paradoxus

b. Your patient has severe respiratory distress and is taken straight to the resuscitation room. Describe the initial emergency management of this patient.

• monitored bed
• supplemental oxygen therapy - maintain SaO2 > 95%
• NIV with BiPAP
• continuous salbutamol nebulisers
• ipratropium 500 mcg q20/60 x 3 doses, then q6H
• steroid therapy - prednisone or hydrocortisone (should be give an appropriate dose)

c. Your patient continues to deteriorate despite your aggressive initial efforts. What additional interventions could you offer this patient?

• intravenous salbutamol
• magnesium
• ketamine
• adrenaline
• intubation and mechanical ventilation
• inhalational anaesthetic agents

This issue of "The Probe" covers chylothorax and pregabalin.

This edition of "The Probe" covers all you need to know about intussception.

VBG's are commonly used as a guide for therapy for patients presenting with SOB, but there has not been much evidence looking at the correlation of pH and PCO2 between arterial and venous samples.

• Kelly and Klim have looked at the correlation of pH and PCO2 between arterial and venous samples in a group of 53 patients on NIV with 89 sample pairs being evaluated.
  
• These were predominantly in patients with COPD (43%) and APO (40%)
• The mean difference in pH was 0.04 (95% CI -0.02 - 0.11)
• The mean difference in PCO2 was -8.02 mmHg (95% CI -22.63 - 6.58)
• They concluded that there was good correlation with the pH, but poor correlation with the PCO2.

Take Home Message - in patients with respiratory distress from COPD and APO on NIV, use an arterial sample to accurately ascertain respiratory status (PCO2).

Reference
Kelly AM, Klim S. Agreement between arterial and venous pH and pCO2 in patients undergoing non-invasive ventilation in the emergency department. EMA 2013 (Early Online - DOI: 10.1111/1742-6723.12066)

This edition of "The Probe" covers a clinical case of tibial avulsion, and the management of meningitis in children.

A 68 year old male presents to the ED with chest pain.
He has a history of IHD with minor triple vessel disease on a recent coronary angiogram, and has hypertrophic cardiomyopathy.
His physical examination reveals a systolic murmur and a S4 heart sound.
ECG is unremarkable.
CXR is within normal limits.
Bloods including serial troponins are normal.

What are the common symptoms of hypertrophic cardiomyopathy?

• SOB (especially exertional symptoms) with progressive heart failure
• Palpitations (Atrial Fibrillation is the most common arrhythmia)
• Chest Pain
• Syncope

What are the clinical findings in hypertrophic cardiomyopathy?

• JVP is not usually elevated
• S4 is commonly present
• Systolic ejection murmur heard loudest at the left sternal edge.
• Murmur increased on standing and straining on valsalva (reduces LV filling pressures)
• Murmur reduced on squatting, passive leg extension and hand grip (increases LV filling pressures)

How would you manage this patient?

• Patients may present with chest pain which may be similar to angina.
• Chest pain related to hypertrophic cardiomyopathy is thought to be related to microvascular ischaemia.
• It is unlikely that this patients chest pain is anginal in nature given the recent angiogram result, so the pain is most likely related to the hypertrophic cardiomyopathy.
• Chest pain can be challenging to manage. Symptomatic management is with the use of beta-blockers or verapamil.

Management of Atrial Fibrillation in hypertrophic cardiomyopathy?

• Most common arrythmia - occurs in 20% of patients.
• Increased risk of stroke - 4 times that of the general population
• Amiodarone is the most effective medication for preventing recurrences
• The CHADS score is not validated in this patient group, and oral anticoagulation with warfarin is recommended for most patients with recurrent episodes of AF.

References

1. Maron BJ, Maron MS. Hypertrophic Cardiomyopathy. Lancet 2013. 381; 242-255

 

This edition of "The Probe" covers the use of inotropes and vasopressors. It also covers the management of acute rhinosinusitis.

This weeks edition of "The Probe" covers base of skull fractures, and analgesia in palliative care patients.

Erythema infectiosum or Fifth disease is a viral infection caused by human parvovirus B19. It is also known as "Slapped Cheek Syndrome".

It is commonly seen in pre-schoolers and children of school age.

It presents with an erythematous rash of the face with perioral sparing. The rash progresses to the chest and limbs. It then undergoes central fading and develops a lacy pattern. The rash can last for up to 1-2 weeks. Onset of exanthem is approximately 17-18 days following innoculation.

Patients can also have fever and arthritis.

In patients with haemalytic anaemia's, an aplastic crisis may be precipitated.

The differential diagnosis includes measles, rubella, roseola and infectious mononucleosis. Bacterial infections (scarlet fever), drug reactions and skin conditions such as guttate psoriasis, papular urticaria, atopc dematitis and erythema multiforme should also be considered.

Once the rash has appeared the patient is NOT considered infectious.

Patients should avoid contact with pregnant women as this is the leading cause of hydrops fetalis, and can cause foetal death.

Post-lumbar puncture headache occurs in 3-36% of patients. This rate may be even higher if a traumatic needle is used.

Although epidural blood patching is effective, it is an invasive treatment that is typically performed by an anesthesiologist or interventional radiologist, so in the ED a pharmacological approach would be preferred.

A Cochrane review found only 1 small, high-quality study reporting results indicating that intravenous caffeine is effective for treating post–lumbar puncture headache. In this trial of 41 patients with post–lumbar puncture headache, a single intravenous dose of 500 mg of caffeine resulted in an absolute risk reduction of 61% in persistent headache at 1 to 2 hours. Although the magnitude of effect is impressive (number needed to treat 1.6), 30% of the caffeine-treated patients had post–lumbar puncture headache recurrence, though no timeframe was specified.

There have been individual trials reporting statistical and clinical significance for gabapentin, theophylline and hydrocortisone, however these trials were limited by high degrees of bias and currently have no application in the ED setting.

Take Home Message - Intravenous Caffeine is effective in treating post-lumbar puncture headache, but has a high recurrence rate.


Reference.

1. Benton R. Hunter, Rawle A Seupaul.  Are there pharmacologic agents that safely and effectively treat post-lumbar puncture headache? Annals of Emergency Medicine. 2013; 61(1); 84-85
   
   

 


 

Abdominal pain is a commmon presentation in the ED. This well designed RCT looked at the effectiveness of paracetamol, hyoscine and a combination of the two. 
Bottom line - paracetamol alone outperformed the other combinations, and should be used as a first line agent for mild to moderate abdominal pain. There is no benefit from adding in hyoscine.


Remington-Hobbs, Petts G, Harris T
Emergency department management of undifferentiated abdominal pain with hyoscine butylbromide and paracetamol: a randomised control trial.
Emerg Med J 2012;29:989-994 doi:10.1136/emermed-2011-200474

Abstract
Objective; To compare the effectiveness of paracetamol, hyoscine butylbromide and the combination of paracetamol plus hyoscine butylbromide (paracetamol + hyoscine butylbromide) in the management of patients with acute undifferentiated abdominal pain attending the emergency department (ED).

Setting; A large teaching hospital with an annual ED census of 120 000 adult patients.

Methods; A prospective, randomised placebo controlled trial of a convenience sample of patients attending the ED. The trial compared the analgesic effect of intravenous hyoscine butylbromide, oral paracetamol and the combination of both drugs using a Visual Analogue Scale pain scoring tool. Rescue analgesia was administered when pain was inadequately controlled by trial medication.

Results; 132 patients were recruited to the trial. At 30 min, all analgesic combinations produced significant similar levels of pain relief. At 60 min after administration of the trial medication, mean reductions in pain scores for patients receiving paracetamol only were significantly greater than those receiving paracetamol + hyoscine butylbromide (ANCOVA model, p=0.0180). No relationship was seen between treatment arm and the need for rescue analgesia (χ2, p value=0.846).

Conclusion; The trial data suggest that oral paracetamol is at least as effective as intravenous hyoscine butylbromide and a combination of both drugs in the management of acute undifferentiated abdominal pain presenting to the ED. Based on these results and factors such as cost and tolerability, we recommend single agent paracetamol as the agent of choice for the management of acute mild to moderate undifferentiated abdominal pain.

Pulmonary embolism is an important diagnosis not to miss in the emergency department. There are clinical decision rules that have been developed and validated that can reduce the time spent in work-up and the number of investigations ordered for patients who may have a PE.
In a recent study, investigators looked at the number of CTPA (CT Pulmonary Angiograms) that could have been avoided using an approach of Wells and PERC scores or Wells score and D-Dimer assay according to the patients level of risk.
They found that 9.2% of patients in the PERC group could have avoided a CTPA and 13.8% of patients in the D-dimer group could have avoided a CTPA provided the clinical decision rules were followed.
While this is a small study (152 patients), it points out an important point - we are ordering too many CT scans on our patients - especially if there are validated clinical decision rules which allow us to rule out PE.

Reference

1. Crichlow A et al. Overuse of computed tomography pulmonary angiography in the evaluation of patients with suspected pulmonary embolism in the emergency department. Academic Emergency Medicine. 2012; 19(11);1219-1226

Blood loss is a major cause of mortality in trauma, and fluid resuscitation is an important part of the management of trauma. Over the last few years, fluid resuscitation has changed from high volumes to the concept of damage control resuscitation.

Who needs Damage Control Resuscitation (DCR)?

• Patients who are estimated to require 4 Units of blood in the first 2-4 hours.
  
• There are a number of tools which can predict this, but they have been shown to be just as good as physician gestalt.

How do you identify patients in shock?

• A systolic BP < 90 is commonly used to define shock and hypotension, however there are studies that show worse outcomes with a BP < 110.
• Basic physiological parameters will only identify patients in advanced haemorrhagic shock. There are patients with normal vital signs who have cryptic hypovolaemic shock, and these patients have increased mortality.
• Metabolic assessment with lactate and base excess also predicts outcomes, but may be falsely low if patient is hypoperfused, or elevated if exercising at the time if the injury.
• In patients with central venous access, mixed venous oxygen saturation is a good indicator of blood loss with levels < 70% suggestive of inadequate oxygen delivery to tissues.

Hypovolaemic Resuscitation

• Concept of minimisation of fluid resuscitation until definitive haemorrhage has been completed
• Trials demonstrate survival advantage in patients with penetrating torso injury and evidence of no harm in blunt trauma.
• Fluid resuscitation should be with 250 mL fluid boluses to a SBP of 80 mmHG or a palpable radial pulse.

Traumatic Brain Injury

• Mortality doubles if blood pressure less than 90 mmHg.
• Guidelines recommend maintaining blood pressure greater than 90 mmHg, but there is no evidence from studies currently.

Haemostatic Resuscitation

• Trauma induced coagulopathy (TIC) is a process that occurs within several minutes of the incident.
• Treatment of this process is volume replacement with blood products (FFP, platelets and packed cells)
• Current consensus is that plasma should be given from the begining of the resuscitation in a ration of 1 unit of FFP to 1 unit of packed cells. Little is known about the effectiveness of platelet transfusion for TIC.
• There is some evidence that fibrinogen replacement (in the form of cryoprecipitate) improves survival benefit and reduces the need for blood transfusion.
• Standard coagulation tests take too long to direct the course of the resuscitation, but thromboelastrography is currently being investigated as a potentially useful point of care test.
• Tranexamic acid is an antifibrinolytic that has been shown to reduce mortality provided it is given within 3 hours of injury.

References

1. Harris T et al. Early fluid resuscitation in severe trauma. BMJ. 2012; 345;e5752 doi: 10.1136/bmj.e5752

Many patients that are discharged from the ED do not understand their diagnosis, management and follow-up.
This was reflected in a study by Engel et al which showed that 80% of patients were unaware of how to care for themselves at home or when to follow-up, and up to 20% of patients were unsure of their diagnosis or what medications to take.
So what information do we need to provide?

• Name of treating doctor
• Provisional diagnosis
• Management plan
• Potential side effects of treatment
• Specific follow-up instructions (include pending investigations to follow-up)
• When to represent  for assessment

This information should be provided verbally and written in clear unambiguous language.
Remember not to use medical jargon when providing instructions.
One way of improving our quality of care is by the use of checklists, and standardising our discharge process. Using this approach, this could improve patient's understanding of their condition and management. 

References;

1. Gawande A. The Checklist Manifesto: How to get things right
2. Engel K et al. Instructions: Where are knowledge deficits greatest? Academic Emergency Medicine. 2012; 19; 1035 - 1044.
3. Keijzers G, Del Mar C. Can emergency physicians improve quality of care by using checklists and going HOME? Emergency Medicine Australasia. 2011; 23; 659-662    
   

A 30 year old male is brought into ED following an attempted hanging with a rope. 
On examination, he has a hoarse voice and a ligature mark in zone 1 of the neck. Neurological examination is normal.
CT angiogram of the neck reveals a dissection of the carotid artery.

How should this injury be managed?

Chronic cough is a cough that persists longer than 8 weeks in duration. As with chronic pain, a cough can have a central sensitisation syndrome with symptoms such as;

• laryngeal parasthesia's (abnormal thraot sensation)
• hypertussia (increased cough sensitivity in response to known triggers)
• allodynia (cough triggered by non-tussive stimuli)

Traditionally, most cough therapies have been ineffectual or in the case of opiates (which do work), have problems with tolerance and addiction. Gabapentin is a GABA analogue that works on central calcium channels (inhibiting excitatory neurotransmitters) and on NMDA receptors, and have been used with sucess in the treatment of chronic pain. Since chronic cough with central sensitisation has similar proposed mechanisms of action, it follows that gabapentin should be useful in the management of chronic cough.
In a randomised double blind placebo controlled trial, the use of gabapentin in the treatment of chronic cough showed significant improvements in all the parameters measured (quality of life score, cough severity and number of coughs per hour and cough reflex sensitivity to capsaicin). The NNT was 3.58 for a clinical improvement. Side effects occured in 31% of the patients taking gabapentin (mostly mild with nausea and fatigue). When the trial drug was stopped all of the patients redveloped their initial symptoms.

In the emergency department (ED), most of our patients seeking relief from a cough will have an acute cough that is usually peripheral in nature, so it is important to remember that this therapy is not for patients with an acute cough.
Occasionally, we will come across patients with chronic cough that needs treatment. While chronic cough needs a complete evaluation which we are unable to provide in the ED, starting gabapentin in the ED will give these patients relief of their symptoms. Gabapentin is attractive in that it has minimal side effects and is generally well tolerated.
In the study, the initial dosage of gabapentin was 300 mg. This was increased by 300 mg each day until side effects developed, symptoms ceased or a maximum of 1800 mg per day was reached.

The utility of drugs in resuscitation of patients with OHCA remains unclear. There is an increasing amount of literature that does not show a survival benefit for drugs in all forms of cardiac arrest (VF/VT, Asystole, PEA).
This study, while it's main focus was on the variable drug use in OHCA also showed no survival benefit with lignocaine and amiodarone for VF / VT or atropine, sodium bicarbonate and adrenaline in asystole or PEA.

Wide variability in drug use in out-of-hospital cardiac arrest: A report from the resuscitation outcomes consortium
Benedict M. Glover, Siobhan P. Brown, Laurie Morrison, Daniel Davis, Peter J. Kudenchuk, Lois Van Ottingham, Christian Vaillancourt, Sheldon Cheskes, Dianne L. Atkins, Paul Dorian, the Resuscitation Outcomes Consortium Investigators. Resucitation. 2012; 83(11); 1324 - 1330

Background: Despite the publication and dissemination of the Advanced Cardiac Life Support guidelines, variability in the use of drugs during resuscitation from out-of-hospital cardiac arrest may exist between different Emergency Medical Services throughout North America. The purpose of this study was to characterize the use of such drugs and evaluate their relationship to cardiac arrest outcomes.

Methods and Results: The Resuscitation Outcomes Consortium Registry-Cardiac Arrest collects out-of-hospital cardiac arrest data from 264 Emergency Medical Services agencies in 11 geographical locations in the US and Canada. Multivariable logistic regression was used to assess the association between drug use, characteristics of the cardiac arrest and a pulse at emergency department arrival and survival to discharge. A total of 16,221 out-of-hospital cardiac arrests were attended by 74 Emergency Medical Services agencies. There was a considerable variability in the administration of amiodarone and lidocaine for the treatment of shock resistant ventricular tachycardia/ventricular fibrillation. For non-shockable rhythms, atropine use ranged from 29 to 95% and sodium bicarbonate use ranged from 0.2 to 73% across agencies in the 89% of agencies that used the drug. Epinephrine use ranged from 57 to 98% within agencies. Neither lidocaine nor amiodarone was associated with a survival benefit while there was an inverse relationship between the administration of epinephrine, atropine and sodium bicarbonate and survival to hospital discharge.

Conclusions: There is considerable variability among Emergency Medical Services agencies in their use of pharmacological therapy for out-of-hospital cardiac arrests which may be resolved by performing large randomized trials examining effects on survival.

CPR teaching has evolved recently with the new adage of "push hard, push fast" being expounded. However, we need to remember that we should not push too fast, A recent paper shows that increasing the rate of CPR leads to a reduced chest compression, and this in turn may lead to decreased cardiac output from the CPR.

Excessive chest compression rate is associated with insufficient compression depth in prehospital cardiac arrest
Koenraad G. Monsieurs, Melissa De Regge, Kristof Vansteelandt, Jeroen De Smet, Emmanuel Annaert, Sabine Lemoyne, Alain F. Kalmar, Paul A. Calle. Resuscitation. 2012; 83(11);1319-1323

Abstract: Background and goal of study: The relationship between chest compression rate and compression depth is unknown. In order to characterise this relationship, we performed an observational study in prehospital cardiac arrest patients. We hypothesised that faster compressions are associated with decreased depth.

Materials and methods: In patients undergoing prehospital cardiopulmonary resuscitation by health care professionals, chest compression rate and depth were recorded using an accelerometer (E-series monitor-defibrillator, Zoll, USA). Compression depth was compared for rates <80/min, 80–120/min and >120/min. A difference in compression depth ≥0.5cm was considered clinically significant. Mixed models with repeated measurements of chest compression depth and rate (level 1) nested within patients (level 2) were used with compression rate as a continuous and as a categorical predictor of depth. Results are reported as means and standard error (SE).

Results and discussion: One hundred and thirty-three consecutive patients were analysed (213,409 compressions). Of all compressions 2% were <80/min, 62% between 80 and 120/min and 36% >120/min, 36% were <4cm deep, 45% between 4 and 5cm, 19% >5cm. In 77 out of 133 (58%) patients a statistically significant lower depth was observed for rates >120/min compared to rates 80–120/min, in 40 out of 133 (30%) this difference was also clinically significant. The mixed models predicted that the deepest compression (4.5cm) occurred at a rate of 86/min, with progressively lower compression depths at higher rates. Rates >145/min would result in a depth <4cm. Predicted compression depth for rates 80–120/min was on average 4.5cm (SE 0.06) compared to 4.1cm (SE 0.06) for compressions >120/min (mean difference 0.4cm, P<0.001). Age and sex of the patient had no additional effect on depth.

Conclusions: This study showed an association between higher compression rates and lower compression depths. Avoiding excessive compression rates may lead to more compressions of sufficient depth.