PE remains among the most discussed entities in medicine. The condition is known to be common, potentially deadly, and a clinical chameleon. This combination that has led to fear, uncertainty, and frequent over-testing. The irony is that PE is among the most well studied topics in clinical medicine. Therefore this month we studied the studies, and we have some surprising answers. To our delight we found that the data offers us a validated, rational approach to PE diagnosis that can reduce testing, and let our patients rest easier. All it took was a deep dive....

At 14 million outpatient visits each year pharyngitis (sore throat) is a common complaint in any emergency department. This is an arena, however, where professional society guidelines and conventional teaching do not do justice to the existing data. We scoured the world’s literature for high quality data, and offer a comprehensive review of potential benefits and harms of antibiotic and symptom therapy for streptococcal pharyngitis.

Keeping Up - Update 16

Rea TD et al. CPR with Chest Compression Alone or with Rescue Breathing. N Engl J Med July 2010;363:423-33.

Study Question: Which is better, for bystanders to do CPR with chest compressions only or CPR plus rescue breathing?

Results: In this multicenter, randomized controlled trial, 981 received dispatcher instructions for chest compressions (CC) alone, and 960 received CC plus rescue breathing (RB) instructions.  The groups were well matched at randomization.  For the primary outcome of survival to hospital discharge, there was no significant difference between CPR methods (12.5% CC vs. 11% CC+RB, p = 0.31) nor was there a difference in neurologically intact survival (14.4% CC vs. 11.5% CC+RB, p = 0.13).  There was 2% crossover between CPR methods, with more moving from CC+RB to CC alone than vice versa.  Also, though both groups were instructed to do CC, the CC alone group was more likely to have bystanders perform CC than those instructed to do both CC and RB (80.5% CC vs. 72.7% CC+RB, p<0.001).  In predefined subgroup analysis, those with a cardiac cause of arrest had improved neurologically intact survival with CC alone (18.9% vs. 13.5%, p = 0.03).

Limitations: The fact that more bystanders randomized to CC alone actually did CC at all may have led to the trend toward improved survival.  They would have needed almost twice as many patients for the difference in neurologically intact survival to show a statistically significant difference.  A 15:2 compression to ventilation ratio was used; the current 30:2 ratio may have given a different outcome.

Take Home: CPR with CC alone is much simpler, less messy, and appears to have a slight advantage of CC+RB, especially in those with a cardiac cause of arrest.

Level of Evidence: 1

Svensson L et al. Compression-Only CPR or Standard CPR in Out-of-Hospital Cardiac Arrest. N Engl J Med July 2010;363(5):434-42.

Study Question: In witnessed arrest, is compression-only CPR better or worse than standard CPR?

Results: This prospective, Swedish study randomized 3,809 patients into compression-only CPR or standard CPR groups.  Both groups received EMS dispatcher instructions as how to perform CPR.  Data was available for 1,276 patients (33%).  Primary outcome was 30-day survival and was 8.7% in the compression-only group and 7.0% in the standard CPR group (not statistically significant).

Limitations: There was significant chance of a type II error with this study (sample size too small to determine a difference), as this was underpowered for their initial and revised calculations.  Large amounts of patients were excluded (2,532 patients) for various reasons.  It would have been nice to analyze those excluded, because CPR was already started or the caller knew how to perform CPR (375 patients).  Also, we do not know how well people followed the dispatcher instructions.

Take Home: Honestly, I just want bystanders on the chest and pushing.  The only breaths they should take are for themselves as they are pushing.

Level of Evidence: 1

Kitamura T et al. Bystander-Initiated Rescue Breathing for Out-of-Hospital Cardiac Arrests of Noncardiac Origin. Circulation July 2010;122:293-9.

Study Question: What if arrest is from a non-cardiac etiology: standard CPR or compression only?

Results: This was a prospective, observational study from Japan's arrest registry that found > 43,000 patients with non-cardiac cause of arrest.  Of these, about 60% had no bystander CPR; 7,474 had conventional CPR, and 8,878 had chest compression (CC) only CPR.  The conventional CPR group had more survivors (1.8%) to hospital discharge and more neurologically intact survivors than CC only CPR.

Limitations: The overall survival rates, regardless of CPR type, were abysmal compared Rea et al covered earlier in the podcast, which had survival to discharge in non-cardiac cause of arrest 5-7%.  Also, more people in the CC only group were in asystole on first rhythm check (59.7% CC vs. 59.4% conventional).  EMS response times were slow, averaging about 11.5 minutes.  This study had a high percentage classified as non-cardiac etiology, >45%, compared with 30% in the Rea study.

Take Home: This study agrees with the Rea and Svensson interventional trials we discussed today: if arrest is not from a cardiac etiology, do conventional CPR.  But in undifferentiated arrest, the patient is more likely to have neurologically intact survival with chest compressions only.

Level of Evidence: 2

Kontos MC et al.  Emergency physician-initiated cath lab activation reduces door to balloon times in ST-segment elevation myocardial infarction patients. Am J Emerg Med in press 2010;doi:10.1016/j.ajem.2010.03.025.

Study Question: How much better are door-to-balloon (D2B) and cardiac cath lab activation (CCL) times by utilizing recommendations from the ACC D2B project?

Results: This retrospective case series evaluated the D2B and CCL times after implementing three processes in a stepwise fashion: single call serves as a global page to activate, EP activation, and EP+EMS activation.  295 patients were analyzed.  Times were better with EP and EMS activation, and a greater proportion of patients met the 90-minute D2B guidelines.

Limitations: Multiple processes were improved during this study, including upstream from the ED that surely helped the times.  The study was observational at one tertiary academic center.

Take Home: In order to improve D2B and CCL times, work with your cardiology and EMS colleagues to develop protocols allowing prehospital activation and ED activation with a single phone call/paging system.  Our job is to get them as quickly and safely as possible to the cath lab; the rest is left to the cardiologists.

Level of Evidence: 3

Amsterdam EA et al. Testing of Low-Risk Patients Presenting to the Emergency Department With Chest Pain: AHA Scientific Statement. Circulation August 2010;122:756-76.

Study Question: What is the current best evidence for the diagnostic tools we use in working up low risk chest pain patients?

Results:

- Determining "low risk" means patients have no coronary artery disease (CAD) or prolonged pain (<20 min) or they have a low clinical risk score (i.e. TIMI risk score), normal or near-normal ECG, and negative cardiac injury biomarkers.

- Chest pain units are useful in assessing low risk patients by utilizing serial ECG and serial cardiac biomarkers.

- An accelerated diagnostic protocol (ADP) takes into account history, exam, ECG, biomarkers, CXR, and often confirmatory testing.

- Confirmatory tests include the exercise treadmill test (ETT) with 70% sensitivity and 75% specificity.  Adding to the ETT are myocardial perfusion imaging (MPI) and stress echocardiogram, with sensitivities of 86-87%.  Radiation is the disadvantage of MPI, while echo has lower NPV (89-100%).  Pain MPI and pain echo are less sensitive alternatives.  Stress testing can be done within 72 hours if patients are low risk with no chest pain, normal ECG, and negative biomarkers.

- Coronary CTA is helpful if normal in a low risk patient but requires ionizing radiation and IV contrast and can only be done in select patients able to breath-hold and having slow heart rates.  MRI is an emerging technology for this application.

- Elderly, diabetic, and patients with known CAD are at higher risk.  For us in the ED, involve cardiology in the decision making.

- What about chest pain unit recidivism, occurring in 21-26%?  In other words, what is the warranty period for a negative initial work up?  Patients with normal stress MPI had 1.1% risk of cardiac event in 2-year follow up, but those with higher baseline risk had 1.4-1.8% rate of cardiac events.

Limitations: This is an AHA statement based on the authors' interpretation of the literature.

Take Home: In low risk patients, get a couple of ECGs and sets of cardiac injury markers and consider imaging for most of them.

Level of Evidence: This is a literature review.

Dmello D et al. Outcomes of Etomidate in Severe Sepsis and Septic Shock. Chest in press 2010;doi10.1378/chest.10-0790.

Study Question: Is etomidate use for rapid sequence intubation (RSI) harmful in patients with sepsis?

Results: 113/224 patients in this retrospective cohort of patients with severe sepsis or septic shock received etomidate for RSI.  There was no difference in in-hospital mortality, vasopressor use, ICU length of stay, or ventilator days between etomidate and non-etomidate cohorts.  More patients in the etomidate group received steroids.

Limitations: This was retrospective and not interventional.

Take Home: Until etomidate is shown to be associated with adverse outcomes in a large, interventional study, it should be considered safe to use for RSI.

Level of Evidence: 3

Runeson B et al. Method of attempted suicide as predictor of subsequent successful suicide: national long term cohort study. BMJ July 2010;340:c3222.

Study Question: Are all suicide attempts the same?  What is the association between attempt method and subsequent suicide?

Results: This Swedish cohort study followed 48,649 patients admitted between 1973 and 1982 for a suicide attempt.  Patient follow-up ranged from 21 to 31 years.  Of the initial 48,649 patients, 5,740 (11%) patients committed suicide during the follow-up period.  Using poisoning as the reference, the greatest risk (6.2) was with initial attempt by hanging/strangulation/suffocation.  Drowning, firearms, and jumping from heights had hazard ratios greater than 3.  Cutting was equivalent to poisoning.  People tended to use the same method as their initial one and tended to be successful within the 1^st year when more violent methods were employed.

Limitations: The initial cohort included only patients admitted to the hospital.  Poisoning was used as the reference, but it was also the most common method (initial 77% men/90% women and successful 69% men/82% women).

Take Home: Not all suicide attempts are equal - take the method into account.

Level of Evidence: 2

Cotton BA et al. Multicenter Validation of a Simplified Score to Predict Massive Transfusion in Trauma. J Trauma July 2010;69: S33-39.

Study Question: Can we predict who may need mass transfusion (i.e. 10 units PRBCs/24 hours) with simple, readily available variables?

Results: This was a retrospective study using the trauma registries from three institutions and applying the following variables to predict mass transfusion: penetrating mechanism (no = 0/yes = 1), ED systolic blood pressure 120 beats/minute (no = 0/yes = 1), and positive FAST (no = 0/yes = 1).  For a score >=2, the sensitivity ranged from 76-90%, and area under the ROC curve (overall diagnostic accuracy) was 0.83-0.90.

Limitations: This was a retrospective study and relied on accuracy of the FAST exam.

Take Home: If your trauma patient has 2 or more of the above variables, be ready to activate mass transfusion protocols.  More importantly for the ED, have a low threshold to transfuse uncrossmatched "trauma blood" in the ED trauma bay in such patients.

Level of Evidence: 2

Walls RM et al. A new maneuver for endotracheal tube insertion during difficult Glidescope intubation. J Emerg Med July 2010;39(1):86-8.

Study Question: Not a study but rather a technique paper.

Results: Failures with video laryngoscopes are rare; however this case report presents a failure and a technique to overcome that failure.  The difficulty in passing the tube was the steep posterior course of the trachea in relation to the glottic opening.  To overcome this, the endotracheal tube was rotated 180 degrees after passing the vocal cords.  Now the sharp angle of the tube matched the sharp, posterior angle of the trachea and the tube was passed easily.

Limitations: None, technique only.

Take Home: Failures do occur with the Glidescope based on difficulty passing the tube.  Several tricks have been described, but this one worked because the authors actually assessed the anatomy and developed a plan to match the anatomy - the true learning point from this paper.  Always think to yourself, "Why won't this tube pass?"  Then develop a plan to pass the tube.

Level of Evidence: 4

Komatsu R et al. Airway Scope and Macintosh Laryngoscope for Tracheal Intubation in Patients Lying on the Ground. Anesth Analg August 2010;111:427-31.

Study Question: Is an Airway Scope (AWS) or Mac 3 better when intubating a patient lying on the ground?

Results: 100 patients were randomized 50:50 to intubation with one or the other device with the intubator on a table at the level of the patient's head to simulate intubation on the ground (left lateral decubitus at the head with a Mac and kneeling with the AWS).  There was 100% success with the Mac 3 and 98% success with the AWS; the AWS was 17 seconds faster even though it required more attempts.

Limitations: Generalizing this to the prehospital setting in patients with a full stomach, bloody airways, and high ambient light conditions would be difficult.

Take Home: Intubation at ground level is difficult.  Use of an Airway Scope may make it faster.

Level of Evidence: 1

Copyright © Vanderbilt University 2010, All rights reserved  

Keeping Up - Update 15, July 22, 2010

Haukoos JS et al. Routine Opt-Out Rapid HIV Screening and Detection of HIV Infection in Emergency Department Patients. JAMA July 2010;304(3):284-92.

Study Question: Early treatment of new-onset HIV can make a big difference, but identifying cases is difficult.  Could routine, opt-out screening utilizing existing staff in the ED help find more new cases than physician-directed screening?  See Week 26 for a similar article we covered last year.

Results: They compared two 12-month periods during which all patients were tested with a rapid HIV blood test unless they opted out at registration vs. targeted screening based on the physicians' judgment.  During the opt out phase, 24% did not opt out, and of these, 99% were screened, yielding 16/6702 (0.24%) with confirmed HIV, of which 10 were new diagnoses.  Of the patients that opted out but were still tested by their physician, 9/231 (4%) were positive with 5 being new diagnoses.  Of the 15 new diagnoses, only 4 of these had CD4 counts > 350.  During the physician directed phase, 243/29,925 (0.8%) were tested, and 9 were positive, 5 known diagnoses and 4 new (all with CD4 counts < 200).  This did not have a major impact on ED throughput metrics.

Limitations: This was a single center with 0.7% estimated HIV prevalence in the ED population and may not be generalizable.

Take Home: Routine, opt out screening for HIV in the ED identifies more new diagnoses than physician directed screening but does not find more cases of acute HIV.

Level of Evidence: 2

Smith PC et al. A single-question screening test for drug use in primary care. Arch Intern Med July 2010;170:1155-60.

Study Question: Can a single strategic question identify patients in a primary care setting who have a drug abuse problem? Here is the question: "How many times in the past year have you used an illegal drug or used a prescription medication for nonmedical reasons?"

Results: A positive response of drug use >= 1 time was considered positive.  In this study at a safety net academic primary care clinic, the sensitivity of the question was 100% with a specificity of 73.5% for detection of a drug use disorder when compared with a validated multi-question screening tools and oral fluid drug screen.  But it was less sensitive for self reported current drug use and drug use detected by oral fluid screening.

Limitations: Of 1,781 patients approached for screening, only 217 completed the interview and the oral fluid testing.

Take Home: A single question screening tool may be as valid for detecting drug abuse disorders as other currently available and more time consuming screens.

Level of Evidence: 2

Schmitz GR et al. Randomized Controlled Trial of Trimethoprim-Sulfamethoxazole for Uncomplicated Skin Abscesses in Patients at Risk for Community-Associated Methicillin-Resistant Staphylococcus aureus Infection. Ann Emerg Med in press 2010;doi:10.1016/j.annemergmed.2010.03.002.

Study Question: You may remember the abstract from these authors done at ACEP in week 40 last year.  Do we need to give an antibiotic (TMP-SMX) after incision and drainage (I&D) in the era of MRSA?

Results: Their abstract initially suggested we should give TMP/SMX; however, the final paper says no.  212 patients were randomized to placebo or TMP-SMX after I&D.  The primary outcome of treatment failure at 7 days showed no statistically significant difference with a 9% trend toward improvement on TMP/SMX (95%CI, -2 to 21%).  At 30-day follow up, 14/50 (28%) of placebo patients had new lesions vs. 4/46 (9%) of TMP-SMX patients (p = 0.02).  Overall, 53% grew MRSA, and all were sensitive to TMP-SMX.

Limitations: These were simple, uncomplicated abscesses in fairly healthy people.  One center did not record 30-day outcome data, and those patients were excluded.  10% and 31% were lost to follow up at 7 days and 30 days, respectively.

Take Home: TMP-SMX does not appear to reduce treatment failure after I&D of uncomplicated abscesses but may reduce recurrence.  See the recent Keeping Up summary of Duong et al and the Week 40 summary of this group's ACEP abstract.

Level of Evidence: 1

Simpson P et al. Delayed versus immediate defibrillation for out-of-hospital cardiac arrest due to ventricular fibrillation: A systematic review and meta-analysis of randomized controlled trials. Resuscitation August 2010; 81:925-31.

Study Question: Does delayed defibrillation after 60-90 seconds of CPR in the out-of-hospital cardiac arrest vs. immediate defibrillation result in more survival to hospital discharge?

Results: A meta-analysis of 3 randomized controlled trials was performed and demonstrated no benefit from providing 90-180 seconds of CPR prior to defibrillation compared to immediate defibrillation for an outcome of survival to hospital discharge.  Analysis of ambulance response time (5 min) also showed no difference in survival rates between immediate and delayed defibrillation.

Limitations: There are limited numbers of prospective, randomized, or pseudo-randomized trials that include outcome data of survival to hospital discharge.  This meta-analysis was based on 658 patients and there was low to moderate heterogeniety.

Take home: There is not enough prehospital data to support changing current protocols regarding defibrillation.

Level of Evidence: 1

Tibballs J et al. Biphasic DC shock cardioverting doses for paediatric atrial dysrhythmias. Resuscitation in press 2010;doi:10.1016/j.resuscitation.2010.04.028.

Study Question: Current recommended doses for pediatric supraventricular tachycardia are 0.5 - 1.0 J/kg.  What is the best energy dose for cardioverting pediatric atrial dysrhythmia?

Results: 25 children had 40 episodes of atrial dysrhythmia requiring biphasic DC cardioversion.  This was a prospective observational study recording age, weight, dose, rhythm, and outcome.  Of all 40, first shock success was 62.5%.  2/8 (25%) converted with 1.0 J/kg.  For internal paddles, the average converting dose was 0.4 J/kg.

Limitations: This was observational not interventional, and there was no assessment of myocardial injury with varying doses.

Take Home: Closer to 1.0 J/kg may be better for first-time success in cardioverting pediatric atrial dysrhythmia.

Level of Evidence: 2

Hostler D et al. Increased survival after EMS witnessed cardiac arrest. Observations from the Resuscitation Outcomes Consortium (ROC) epistry - cardiac arrest. Resuscitation July 2010; 81:826-830.

Study Question: Is survival improved after an EMS witnessed cardiac arrest compared to an unwitnessed or bystander witnessed?

Results: Using data from the ROC (10 centers) of 9,991 cases, 10% were EMS witnessed, 34% were bystander witnessed, and 56% were unwitnessed.  PEA was the predominant first recorded rhythm with EMS witnessed vs. v-fib/v-tach by the bystander witnessed.  Asystole was the first recorded rhythm in more than half of the unwitnessed cases.  Survival to hospital discharge was 18% in EMS witnessed, 15% with bystander witnessed with bystander CPR, and 3% in the unwitnessed group.

Limitations: The database is prospective, but the study is not.  In a consortium, there may be local variation in EMS training and protocols.

Take home: If you are going to have your v-fib arrest, do it front of EMS personnel or make sure your friend knows CPR.

Level of Evidence: 2

Sas DJ et al. Increasing Incidence of Kidney Stones in Children Evaluated in the Emergency Department. J Pediatr July 2010;157:132-7.

Study Question: Does it seem like you are seeing more kids with kidney stones?

Results: Turns out, you may be!  This was a retrospective study of a South Carolina database using ED data from 1996 - 2007.  They found that the incidence of stones in 1996 was 7.9/100,000 and rose to 18.5/100,000 in 2007.  The increase occurred primarily in pre-teen and teenage Caucasians, with girls slightly outpacing boys.  No significant increase was seen in African-Americans.

Limitations: This was based on retrospective data and ICD-9 code in one southeastern state.

Take Home: Incidence of kidney stones is increasing in pre-teens and teens, at least in S. Carolina.

Level of Evidence: 2

Wilson M et al. Potential complications of combining intramuscular olanzapine with benzodiazepines in emergency department patients. J Emerg Med in press 2010; doi:10.1016/j.jemermed.2010.04.012.

Study Question: Data may suggest that olanzapine may have the efficacy without as much of the side effects of movement disorders compared to haloperidol.  Is there any concern for using benzodiazepines with intramuscular olanzapine for chemical sedation of patients with acute agitation?

Results: This retrospective chart review of a 3-year period demonstrated 25 patients who met criteria for inclusion.  Co-administration of olanzapine and a benzodiazepine was defined if both medications were given within 30 minutes of each other.  Olanzapine as a single agent was used in 15 patients, and 10 patients had the combination with benzodiazepines.  There were no clinically significant changes in blood pressure or respirations regardless of group; however, oxygen saturations tended to drop (defined as <=92%) in the combination group who also had ethanol intoxication.  If no booze on board, there was little change in oxygen saturation.

Limitations: This was a small study with no standardization of data collection, such as the degree of agitation requiring some patients to receive the combination rather than just olanzapine, nor was there a record of serial vital signs.

Take home: Make sure patients with acute ethanol intoxication are monitored, particularly if medications are needed for chemical sedation.

Level of Evidence: 3

Takayesu JK, Walls RM et al. Incorporating simulation into a residency curriculum. CJEM July 2010;12(4):349-53.

Study Question: Some are skeptical about simulation (sim), despite the proven benefit in other high-pressure, highly technical fields (i.e. landing an airplane on the Hudson River).  How can simulation be successfully incorporated into a residency curriculum?  Here are some strategies from Dr. Ron Walls and colleagues.

Results: Why use sim?  It provides trainees immediate practical use of knowledge and feedback and helps identify performance gaps.  How often?  They use it for 20% of their teaching.  How do faculty help participants learn?  Match complexity to their level of training.  How should sim facilitators prepare?  Study the topic in depth, have supporting materials (i.e. ECGs, x-rays), keep groups small (4-6 people), and train faculty in simulation specifically.  How is sim integrated with the classroom?  For their sim sessions, they spend 90 minutes on didactics and 90 minutes of sim.  For junior residents, didactics should precede sim; for experienced trainees, it is often better to do sim first and then didactics focusing on performance gaps identified in sim. 

Limitations: This is in essence an op-ed based on the way they do sim at Harvard.

Take Home: Simulation can be a valuable tool for learning emergency medicine, but should be fully integrated into the overall curriculum, not added on as an extra.

Level of Evidence: 5

Francis M et al. Effect of an emergency department sepsis protocol on time to antibiotics in severe sepsis. CJEM July 2010;12: 303-10.

Study Question: Does the implementation of a sepsis protocol reduce time to antibiotics in patients who have severe sepsis?

Results: A retrospective review of 213 ED encounters with a diagnosis of severe sepsis (85 patients in 2004, 128 patients in 2006) demonstrated a reduction in the median time to delivery of antibiotics by about 84 minutes.  There was also an improvement in the selection of antibiotic coverage by 26%.  However, time from triage to antibiotic delivery was not statistically significant.

Limitations: This was a retrospective review.  Screening of charts via ICD-9 codes created the study population for both time periods.

Take home: Protocol development may be of benefit to patient care.  Having a protocol for the severe sepsis patients puts all members of the team on the same page and may decrease time to delivery of antibiotics.

Level of Evidence: 2

Copyright © Vanderbilt University 2010, All rights reserved {jcomments on}

Keeping Up - Update 14, July 8, 2010

Kimia A et al. Yield of Lumbar Puncture Among Children Who Present With Their First Complex Febrile Seizure. Pediatrics July 2010;126:62-69.

Study Question: How often do children with complex febrile seizure have acute bacterial meningitis?

Results: This was a retrospective study of 526 children with first complex febrile seizure (CFS); 340 had cerebrospinal fluid (CSF) analysis.  Of these, three had bacterial meningitis; two had positive CSF, and one had a positive blood culture and CSF with too much blood for analysis.  All three grew S. pneumoniae.  Both with positive CSF were unresponsive and ill appearing.  No patients without lumbar puncture (LP) returned with bacterial meningitis.

Limitations: They found cases by a sophisticated text screening computer program, but missed cases could have still occurred.  90% had some sort of follow up information in their electronic medical record, so some could have returned to other facilities with meningitis.  Vaccination rates in Massachusetts are over 90%.

Take Home: Bacterial meningitis is rare even in complex febrile seizure.  If children are ill appearing or unresponsive, have a low threshold to obtain CSF.

Level of Evidence: 2

Antoniou T et al. Trimethoprim-Sulfamethoxazole-Induced Hyperkalemia in Patients Receiving Inhibitors of the Renin-Angiotensin System. Arch Intern Med July 2010;170(12):1045-9.

Study Question: It is well known that the co-administration of ACE inhibitors (ACE-I) or angiotensin receptor blockers (ARB) with potassium sparing diuretics increases the risk of life-threatening hyperkalemia, and trimethoprim has structural and pharmacologic similarities with amiloride.  Does the co-administration of ACE-I ARB with trimethoprim-sulfamethoxazole (TMP/SMX) increase a patient's risk of hyperkalemia?

Results:  To do this the authors conducted a population-based nested case-control study of elderly patients who were older than 65 and on continuous therapy with an ACE-I or ARB and were treated with antibiotics for a UTI.  In addition to TMP-SMX, they examined amoxicillin, ciprofloxacin, norfloxacin, and nitrofurantoin.  They mined records from the Ontario Drug Benefit Program and hospitalization data from the Canadian Institute for Health Information Discharge Data and correlated the recent use of antibiotics with the coded admission diagnosis of hyperkalemia.

They found a major increase in the risk of hyperkalemia-associated hospitalization in patients taking TMP-SMX with ACE-Is and ARBs.  None of the other antibiotics exhibited this effect.  The odds ratio was almost 7.

Limitations: The authors did not have access to the actual lab data, so it is impossible to know how clinically significant the hyperkalemia was or to identify the baseline renal function of the patients.  The authors attempted to control for various confounders, but it is certainly possible that there were differences between the study group and control group.  This study only looked at older patients so the conclusions can't be applied to younger patients.

Take Home: Co-administration of TMP-SMX with an ACE-I or ARB may increase the risk of patients developing hyperkalemia.

Level of Evidence: 3

Chatoorgoon K et al. Unnecessary Imaging, Not Hospital Distance, or Transportation Mode Impacts Delays in the Transfer of Injured Children. Pediatr Emer Care June 2010;26:481-6.

Study Question: What leads to delays in transporting traumatized children to definitive care?

Results: 748 pediatric trauma transfers in the Cincinnati trauma registry were included; 136 were transferred early ( 2 hours).  The late cohort arrived almost 6 hours after the early cohort, had similar injury severity, and was more like to have private insurance.  There was no association between late arrival and any specific referring hospital, distance from the trauma center, or mode of transportation (ground or air).  To assess pre-transfer imaging, 200 patients were randomly chosen for pre-transfer hospital record review (using an algorithm to maintain the same early to late proportion); 185 were available for review.  Of these, demographics and injury severity were essentially the same between early and late transfers.  Late transfers were more likely to have CT (49% vs. 23%) and more likely to have private insurance (74% vs. 58%).  Authors noted that, "48% with private insurance had a pre-transfer CT compared with only 25% of those without private insurance (p = 0.006)."  Nearly half did not have imaging with them or had poor quality imaging, and nearly one-third needed repeat CT.

Limitations: Table 2 has problems; N and % are switched throughout, and the math does not work out for the private insurance row.  This is registry data.  We do not know indications for imaging at the outlying facilities.  Outcome associated with these delays was unfortunately not addressed.  The 27% excluded for missing time of injury were sicker than the cohort studied.

Take Home: Transfer pediatric trauma patients with severe injuries to definitive care without wasting time on CT if you are not equipped to manage what you might find.  Imaging prior to transfer may cause unnecessary delays, often does not help the patient, and frequently necessitates repeat imaging at the trauma center.  This study also suggests that having private insurance and increased imaging correlate.

Level of Evidence: 2

Han JH et al. Delirium in the Emergency Department: An Independent Predictor of Death Within 6 Months. Ann Emerg Med in press 2010; doi:10.1016/j.annemergmed.2010.03.003.

Study Question: Is delirium independently associated with 6-month mortality in older patients, and is this relationship modified by nursing home status?

Results: This was a very well done, meticulously documented study.  In fact, so well documented that if you want a lesson in good study design or have a bad case of insomnia then you need to read the methods section. They use a convenience sample of 628 patients of which 17% were found to be delirious and 9% were from a nursing home.  The CAM-ICU score was performed at enrollment to determine the presence or absence of delirium.  Delirium was found to be an independent risk factor for 6-month mortality (hazard ratio 1.7), even when adjusting for several comorbidities, and this was true regardless of nursing home status.

Limitations: This was a convenience sample, a few patients (2%) withdrew from the study, and these patients were more likely to come from a nursing home. A few subjects' mental status was not static, and some study patients were not delirious at enrollment but became delirious later during their evaluation.   Also about 17% of patients were lost to follow up before 6 months and if there was no death record present in the Social Security Death Index they were pooled into the "not dead" group.

Take Home: Delirium is independently associated with 6-month mortality in older patients.  Consider screening for delirium in older patients with altered mental status.  If you don't look for it, you will likely not find it and it makes a big difference.  Check out an ICU delirium website.

Level of Evidence: 1

Berger-Achituv S et al. Blood Sampling Through Peripheral Venous Catheters Is Reliable for Selected Basic Analytes in Children. Pediatrics July 2010;126:e179-e186.

Study Question: Are labs drawn from a peripheral IV reliable compared to a fresh peripheral venous stick?

Results: 40/47 children had successful paired sampling of a CBC and basic chemistries.  All variables were comparable, regardless of catheter size, with the exception of glucose, which was still similar clinically but did not meet stringent lab quality assurance.  Sampling took about one minute longer with phlebotomy and caused much greater distress.  Hemolysis rates were the same, and sampling did not cause IV clotting, infiltration, or dislodgement.

Limitations: One physician drew all the samples. 

Take Home: Blood sampling via peripheral IV is accurate, faster than a new stick, and much less distressing.

Level of Evidence: 1

Chow A et al. Use of Tissue Glue for Surgical Incision Closure: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. J Am Coll Surg July 2010;211(1):114-25.

Study Question: How does tissue glue perform compared to standard wound closure methods (sutures, staples) in surgical patients?

Results: The authors did a literature search and identified 26 randomized controlled trials that were included in this analysis.  Most of these studies used octyl-cyanoacrylate (Dermabond).  A few studies looked at butyl-cyanoacrylate.  They looked at time for wound closure, wound infection rates, wound dehiscence rates, cosmetic outcomes, patient satisfaction, and cost of the procedure.  Glue was found to be faster and less painful than sutures but slower than staples.  Cosmetic outcomes were comparable to sutures.  Glue had a RR for wound dehiscence of 3.3, and if you were unlucky enough to have your groin wound closed with glue, then your RR increased to 18.  Octyl-cyanoacrylate appeared to be better than butyl-cyanoacrylate.

Limitations: This was a meta-analysis that tried to combine heterogeneous studies to come to a few simple conclusions.

Take Home: Tissue adhesives in surgical patients have a higher rate of wound dehiscence and should be used with caution, particularly in larger wounds and over elastic skin.

Hamilton M et al. Incidence of Delayed Intracranial Hemorrhage in Children After Uncomplicated Minor Head Injuries. Pediatrics  July 2010;126:e33-9.

Study Question: What is the answer when parents ask, "What is the risk of my child having a delayed bleed after leaving the ED?"

Results: This was a retrospective chart review of children < 14 years in the Calgary Health System over an 8-year period that identified almost 18,000 cases of uncomplicated minor head injury.  Two kids with GCS 6 hours.  5/17,962 (0.03%) with normal mental status had a delayed diagnosis > 6 hours, although none had surgery or adverse outcome.

Limitations: This was a retrospective review, relying on ICD-9 codes and may have underestimated the true number of cases.

Take Home: If a child has normal mental status, the chance of deterioration and delayed intracranial bleeding after 6 hours is 3 in 10,000.

Level of Evidence: 2

Harris T et al. Cricoid pressure and laryngeal manipulation in 402 pre-hospital emergency anaesthetics: Essential safety measure or a hindrance to rapid safe intubation? Resuscitation July 2010;81:810-6.

Study Question: How does cricoid pressure and laryngeal manipulation affect the laryngeal view and intubation success rate?

Results: This was performed in London where a doctor-paramedic team responded to incidents.  When patients with a pulse were felt to need intubation they underwent RSI.  A bougie was used in all patients.  The initial intubation attempt was performed using cricoid pressure and standard technique.  If the cords could not be visualized or the bougie could not be passed, then a series of drills were performed to try to facilitate intubation.  These included removal of cricoid pressure, ask for backward upward rightward pressure (BURP), or manipulation of the larynx under direct vision.  A database was set up prospectively, and the doctors completed a standardized paper questionnaire after each mission.  400 intubations were included in the study.  87% were intubated on the 1st pass.  99% in 2 attempts, and all but 1 in 3 attempts.  The authors try to analyze the effect that release of cricoid pressure and use of the laryngeal maneuvers have on laryngeal view and success of intubation and concluded that no significant difference between the 3 maneuvers could be found.

Limitations: I don't think you can really draw any conclusions from this study.  These doctors were able to intubate 399 out of 400 patients in the field, the vast majority on the 1st try using standard cricoid pressure.  There was no structured protocol to define how to proceed if the 1st attempt failed, so the doctors were probably performing the maneuvers that they were most comfortable with and they felt were most likely to be successful.  Even so, they were unable to identify any differences between the techniques.

Take Home: A protocol of RSI using cricoid pressure will allow successful intubation of the vast majority of patients.  If this fails, the techniques of removal of cricoid pressure, BURP, or laryngeal manipulation will result in success in almost everyone.

Level of Evidence: 2

Hakim SM. Cosyntropin for Prophylaxis against Postdural Puncture Headache after Accidental Dural Puncture. Anesthesiology August 2010;113(2):in press.

Study Question: Could cosyntropin (ACTH) be used to prevent dural puncture headache?

Results: 95 obstetrical patients with inadvertent dural puncture during epidural placement were randomized to placebo (saline) or cosyntropin 1mg.  15 (33%) of the treatment group vs. 31 (69%) of controls had post dural puncture headache (PDPH), and 5 (11%) cosyntropin vs. 13 (29%) controls received a blood patch.

Limitations: Patients with diabetes, hypertension, preeclampsia, or infection were excluded, which could limit use in an ED setting.  The needles used for epidural anesthesia are large, up to 16 gauge, and PDPH occurs in about 75%.  This was used in a prophylactic way and not to treat existing PDPH.

Take Home: High dose cosyntropin (ACTH) 1mg could prevent PDPH in obstetrical patients.  How this may translate into use in the ED to treat PDPH remains to be seen.

Level of Evidence: 1

Sell RE et al. Minimizing pre- and post-defibrillation pauses increases the likelihood of return of spontaneous circulation (ROSC). Resuscitation July 2010;81:822-5.

Study Question: There are several studies that show that "off the chest" time may adversely affect arrest outcomes.  These investigators ask, "What are the optimal pre and post-defibrillation pauses for out of hospital cardiac arrest?"

Results: To do this they collected data from 35 arrest victims in San Diego using EMS records.  They looked at a combination of ECG, impedance, and audio recordings to analyzed when patients were getting compressions vs. when they were not.  Data were collected by "trained observers".

The authors determined a pre-shock interval of <3s and a post-shock interval of <6s both led to an increase in ROSC based on receiver-operator curve analysis.

Limitations: There are many.  This is a small study.  There is no mention of the reasons why certain patients may have had a long pre and/or post shock interval.  Maybe the paramedics who perform the best compressions are the same ones with lower pre and post shock intervals.  Maybe these same paramedics are also put in the areas with the shortest response times so they got to the patients more quickly.  I can think of many scenarios where this data could be biased.

Take Home: Perform quality compressions and minimize the time where compressions aren't being performed.  Stay on the chest until just before defibrillation and get back on the chest immediately after the shock is delivered.

Level of Evidence: 2{jcomments on}

Copyright © Vanderbilt University 2010, All rights reserved 

Keeping Up - Update 13, June 24, 2010

Centers for Disease Control and Prevention. Emergency Department Visits Involving Nonmedical Use of Selected Prescription Drugs - United States, 2004-2008. MMWR 2010;59:705-9.

Study Question: Is the non-medical use of use of prescription (Rx) or over-the-counter (OTC) drugs increasing, that is, "taking a higher-than-recommended dose, taking a drug prescribed for another person, drug-facilitated assault, or documented misuse or abuse?"

Results: This drug abuse surveillance network reviewed ED charts from a representative US sample from 2004-2008 and found that abuse of OTC or Rx drugs has more than doubled for opioids (>305,000 visits in 2008) and almost doubled for benzodiazepines.  The MMWR editor calls for, "universal use of state pre­scription drug monitoring programs by providers."

Limitations: This was a chart review, which could only capture what was documented.

Take Home: OTC and Rx drug abuse is out of control, and we need to take some steps to avoid contributing to this epidemic.  Tennessee's Rx monitoring system takes about 1-2 minutes per patient.  Dr. Angela Gardner, ACEP president, opined in USA Today that we should not be the "pain police" and that, "even a minute per patient adds up."  What is your opinion?  Comment on this article!

Level of Evidence: 2

CRASH-2 collaborators. Effects of tranexamic acid on death, vascular occlusive events, and blood transfusion in trauma patients with significant haemorrhage (CRASH-2): a randomised, placebo-controlled trial. Lancet in press 2010; doi:10.1016/S0140-6736(10)60835-5.

Study Question: Tranexamic acid (TA) is a synthetic lysine derivative that inhibits fibrinolysis.  Could this reduce bleeding and death in trauma patients?

Results: This randomized, blinded, placebo-controlled trial included 274 hospitals in 40 countries and enrolled over 10,000 patients in each group.  For the primary outcome, 28-day in-hospital mortality, those who received TA had improved survival (RR 0.91, 95% CI 0.85-0.97, NNT = 66).  There was a counterintuitive, non-significant trend toward fewer vascular occlusive events in the TA group, i.e. myocardial infarction, pulmonary embolism, etc.

Limitations: Measures of fibrinolysis were not measured, so the mechanism of action of TA remains unclear.  Pfizer provided some of the funding and manufactures TA.

Take Home: Tranexamic acid is a promising treatment for trauma patients with life threatening hemorrhage.

Level of Evidence: 1

Lindenauer PK et al. Association of Corticosteroid Dose and Route of Administration With Risk of Treatment Failure in Acute Exacerbation of Chronic Obstructive Pulmonary Disease. JAMA June 2010;303(23):2359-2367.

Study Question: Do COPD patients need high-dose IV steroids or would low-dose oral steroids work just as well?

Results: This retrospective cohort of nearly 80,000 patients with COPD exacerbation found no difference in the primary composite outcome of need for mechanical ventilation, in-hospital death, or readmission within 30 days in the low-dose oral steroid group vs. the high-dose IV steroid group.  Contrary to published guidelines, 92% of all patients received IV steroids.  The oral steroid group was older, had fewer white patients, and had more patients with diabetes, heart failure, and renal failure.  Those who received IV steroids had higher cost and longer hospitalization.

Limitations: Though they used statistical techniques to adjust for the propensity to use IV steroids, potential confounding is possible an observational study such as this.  All patients were not in the ICU.

Take Home: Low-dose (i.e. 60 mg) oral prednisone is as good as high-dose (i.e. 125 mg) IV steroid in non-critical COPD exacerbation and costs less.

Level of Evidence: 2

Litovitz T et al. Emerging Battery-Ingestion Hazard: Clinical Implications. Pediatrics June 2010;125:1168-1177.

Study Question: How have battery ingestions changed over the past several years?

Results: Using National Poison Center and National Battery Ingestion Hotline (NBIH) data, authors learned that larger, greater than 20mm, lithium batteries are increasingly ingested and are associated with more severe outcomes.  Look for the double-rim sign on radiographs to distinguish from coin ingestion.  The Narrower side is the Negative pole and causes Necrosis.  Serious burns and horrific complications may result in only 2 hours!  Please study the treatment algorithm on the NBIH site for your patients' sake.

Limitations: This was based on registry data.

Take Home: Button battery ingestion, if lodged in the esophagus, is a surgical emergency and requires emergent removal in less than 2 hours.

Level of Evidence: 3

LaCalle E et al. Frequent users of emergency departments: The myths, the data, and the policy implications. Ann Emerg Med in press 2010; doi:10.1016/j.annemergmed.2010.01.032.

Study Question: This is a systematic review of the literature of the frequent flyers in the ED.

Results: Although the portrayal of ED frequent flyers (4 or more ED visits per year) is an uninsured patient with primary care complaints, the uninsured represents only 15% of the frequent users and tend to be sicker than occasional users.  Interestingly, 4.5%-8% of patients account for 18-21% of visits.  Also interesting is that frequent users of the ED have more primary care visits with 5 or more outpatient visits being an independent risk factor for frequent ED use.  Having governmental insurance is associated with an odds ratio of 2.1 of being a frequent user.  Unmet medical needs are another risk factor.  High frequency users (20 or more visits) tend to have lower acuity complaints.  Multi-ED users tend to be uninsured.

Limitations: Every ED and its community is different, and the makeup of the community may determine what hospital that gets the frequent users e.g. chronically ill, alcoholics, or public insurance.

Take Home: Common assumptions about frequent flyers are probably not true overall and should not dictate policy.  EDs are going to stay in business and will have frequent flyers; it is just whether or not it is the business you want to be in.

Level of Evidence: 2

Smith SB et al. Early Anticoagulation is Associated with Reduced Mortality for Acute Pulmonary Embolism. Chest in press 2010;doi10.1378/chest.09-0959.

Study Question: Does it matter how quickly we start therapeutic heparin in the ED on patients with acute PE?

Results: 280/400 (70%) had heparin started in the ED, and 325/400 (86%) had a therapeutic aPTT at 24 hours.  Those treated with heparin in the ED had statistically significantly lower in-hospital and 30-day mortality (1.4% vs. 6.7% and 4.4% vs. 15.3%) and significantly reduced length of stay (3.9 vs. 6.6 days, p = 0.001).  More rapid heparin was associated with fewer serious bleeding events.

Limitations: This was a retrospective study, but even after multivariate analysis to adjust for comorbidities increasing the propensity to treat in the ED, the mortality results remained highly significant.  Also, how this applies to low molecular weight heparin is unknown.  Finally, ED length of stay is highly variable and may be more than 24 hours in some institutions.

Take Home: Start anticoagulation for PE in the ED barring contraindications.  It makes a big difference!

Level of Evidence: 2

Sroufe NS et al. Postconcussive Symptoms and Neurocognitive Function After Mild Traumatic Brain Injury in Children. Pediatrics June 2010;125:e1331-39.

Study Question: What is the expected recovery from post-concussive symptoms (PCS) and cognitive deficits for children 10-17 years with mild traumatic brain injury (mTBI)?

Results: This longitudinal, prospective convenience sample compared validated PCS questionnaire results and cognitive testing results among 28 mTBI patients and 45 children with minor non-head injuries.  They found that some non-head injured patients had PCS, but significantly less than those with mTBI, and most with mTBI were markedly improved from baseline at 4-5 weeks.  Also, cognitive testing was the same except for one of the three tests, which was slightly worse in the mTBI group.

Limitations: Almost half the controls and 29% of the mTBI cohort were lost to follow up, and the sample size was small.

Take Home: Students with mTBI may have post-concussive symptoms and subtle neurocognitive changes for up to a month, though most have complete resolution.  Refer patients with concussion to their primary physician, team physician, or to sports medicine to make sure they are ready to return to play.

Level of Evidence: 2

Mark DB et al. 2010 Expert Consensus Document on Coronary Computed Tomographic Angiography. Circulation June 2010;121;2509-2543.

Study Question: What is the expert consensus on coronary CTA?

Results: A negative CTA in a low probability patient is helpful.  Problems with CTA include dealing with the frequent incidental non-cardiac findings.  Also, the triple rule out of coronary disease, PE, and aortic disease is currently not well studied.  Choose your patients wisely.  A patient with slower heart rate, low-pretest probability, no contrast allergy, adequate renal function, who has been informed of the radiation dose required (and has good insurance...it's not cheap) must be selected.  Radiation dose averaged around 12 mSv across multiple studies.  This is comparable to myocardial perfusion imaging and twice that of invasive angiogram but will become less and less as technology improves.

Limitations: This is an expert consensus based on the best available evidence.  Most of the authors had multiple financial relationships to disclose.

Take Home: A negative CTA in a low probability patient is helpful.

Level of Evidence: Expert consensus was based on literature of variable quality.

Fein D et al. Pattern of Pain Management During Lumbar Puncture in Children. Pediatr Emer Care June 2010;26:357-60.

Study Question: How often do children receive some form of pain medication for LP?

Results: This was a retrospective review of 353 children, less than one quarter received pain management.  The younger the patients were, the less likely they were to receive pain medication or sedation.  ED patients were more likely than nursery patients to receive medication (13% vs. 1%).

Limitations: This was a retrospective chart review.

Take Home: There is no reason not to treat pain when performing a pediatric LP.  Do it.

Level of Evidence: 2

Miner MR et al. Randomized clinical trial of propofol versus ketamine for procedural sedation in the Emergency Department. Acad Emerg Med June 2010;17(6):604-11.

Study Question: What is the comparison between propofol and ketamine in adult patients for procedural sedation as far as occurrence of respiratory depression, adverse events, and recovery duration?

Results: In this non-blinded RCT, 97 patients were randomized to 1 mg/kg IV propofol with 0.5 mg/kg every 3 minute or same dose of ketamine IV.  Subclinical respiratory depression was noted in 20/50 propofol group and 30/47 ketamine group.  Median time to return to baseline: 14 minutes ketamine and 5 minutes for propofol.  There were no differences between groups for interventions needed for respiratory depression, median time of procedures, success of procedure, or perceived pain during procedure.

Limitations: There was no standardized protocol as to when to do an intervention for subclinical evidence of respiratory depression.

Take Home: While both propofol and ketamine may work well, ketamine has a longer time to recovery to baseline.  Choose your drug based on the procedure.

Level of Evidence: 2

Copyright © Vanderbilt University 2010, All rights reserved 

2012 "National Spokesman of the Year" for the American College of Emergency Physicians 

Welcome to RyanAStanton.com! Ryan is a board certified Emergency Medicine Physician in Lexington, KY, splitting duties between UK Good Samaritan Hospital and UK Chandler Medical Center.

At Good Samaritan Hospital, Ryan serves as the Medical Director for the ER and is very active in the leadership process of the hospital. He is employed by Marshall Emergency Service Associates while at Good Samaritan.

At UK Chandler Medical Center, Ryan is an Assistant Professor of Emergency Medicine as attending faculty for the UK Department of Emergency Medicine Residency Program which is a three year residency with 24 active residents.

Ryan is active in several state and national medical societies, through presentations and leadership roles. He is currently the Public Relations Chairman and President Elect for the Kentucky chapter of the American College of Emergency Physicians. Ryan has also been named to the Public/Media Relations Committee for the American College of Emergency Physicians. Through ACEP, he regularly contributes to various media outlets.(ACEP Newsmakers)

Media has always been of great interest to Ryan. It all started as a narrator for Sunday services at Munsey Memorial United Methodist Church in Johnson City, TN at the ripe old age of 14. Once in college, he began work with WETS-FM 89.5 NPR for East Tennessee State University. While with WETS, he participated in news editing, board operations, announcing, and program production. Before starting medical school, Ryan spent a summer with WJHL-TV in Johnson City, TN as a production assistant. After a preliminary year in surgery at ETSU, he spent a year performing board operations and on-air work for Clear Channel Radio in Lexington, Ky. He also volunteered for board operations and reading for Central Kentucky Radio Eye, a radio service for the blind in Lexington, which he still continues today. While a resident at the University of Kentucky, Ryan had the opportunity to spend a month as an Intern with the ABC News Medical Unit in Boston, MA, writing stories for ABCnews.com, researching stories for other ABC outlets, and doing some on-air work for ABCNewsNow. Ryan continues to contribute written and video stories for ABC. In December of 2008, Ryan was named the "Doc On-Call" for WTVQ-36 in Lexington, an ABC affiliate. This position involved on-air interviews and segments with WTVQ Health Reporter Kristi Runyon, dealing with common emergency topics and viewer questions. Ryan's most recent venture is "Everyday Medicine", which is a series of short health topics available on WETS-FM and as a podcast. This series will be continuously updated with new topics dealing with health stories that effect people in their every day lives.

Ryan welcomes input and suggestions for new health topics. Feel free to contact him via email at RyanStantonMD@gmail.com and YourEverydayMedicine@gmail.com.

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