Hypertonic saline for elevated ICP (Articles of the Month special edition)

In the June edition of the articles of the month, I included a paper on hypertonic saline for the treatment of traumatic brain injury. My conclusion (and that of the paper’s authors) was that hypertonic saline did not seem to provide any benefit, either in terms of mortality, or even in terms of lowering intracranial pressure. My friend Scott Weingart pointed out that the paper might not actually support that conclusion. The problem was with the studies they included in the review (which I hadn’t read myself). This is probably an excellent lesson: reviews are nice as an introduction to a topic, but expert clinical practice really requires a familiarity with the original literature. For example, there are many reviews that conclude that tPa is excellent for ischemic stroke, but… well I guess I won’t get into that here. Anyhow, I promised to read the studies on hypertonic saline in a little more depth and post an update, so that is what follows.

Continue reading “Hypertonic saline for elevated ICP (Articles of the Month special edition)”

Articles of the month (March 2015)

A monthly collection of the most interesting emergency medical literature I have encountered

Magnesium the wonder drug, now for migraines

Shahrami A et al. Comparison of therapeutic effects of magnesium sulfate vs. dexamethasone/metoclopramide on alleviating acute migraine headache. J Emerg Med 2015; 48(1): 69-76. PMID 25278139

In this RCT, they compared IV magnesium (1 gram) to the combination of metoclopramide 10mg IV and dexamethasome 8mg IV. Magnesium was more effective at 20min, 1 and 2 hours. I would note, that although metoclopramide is what we generally have to use now because of drug shortages or silly rules, prochlorperazine (Stemetil) and droperidol are both better for migraine. Also, previous studies of metoclopramide in migraine have used a 20mg dose, although 10mg is what tends to be ordered.

Bottom line: Intravenous magnesium might be a useful tool in the treatment of migraines

 

This PROMISEs to be the biggest paper of the month

The ProMISe trial. Mouncey et al. Trial of Early, Goal-Directed Resuscitation for Septic Shock. NEJM. 2015 (Ahead of print). PMID: 25776532

This is the third and final large trial of early goal directed therapy for septic shock, and shockingly it tells us pretty much the same thing the first two did: EGDT adds nothing to usual care. This is an open label, multi-center RCT from the UK with a total of 1260 patients. Patients were randomized to receive the classic EGDT protocol or ‘usual care’. There was no difference in mortality, (29% at 90 days). Of course, ‘usual care’ may look a lot more like EGDT than it used to.

Bottom line: Septic patients need antibiotics, fluids, and most importantly someone to care about them. Ditch the high tech stuff.

 

Emergency doctors are ECG experts, we don’t need a second opinion next week

Proano L et al. Cardiology electrocardiogram overreads rarely influence patient care outcome. Am Jour Emerg Med 2014;32(11):1311-14. PMID: 25200503

This is a retrospective review at a single teaching hospital over 21 months, with 38,490 ECGs reviewed. Of the 16,011 patients that were discharged, 22 patients required follow up for discordant readings (0.1%). Of those 22, after review only 2 were determined to require a change in management. The remainder were considered ‘non specific’ or the ED doc turned out to be right. Of the 2 with changed management, one was for ‘possible ACS’ who ultimately had a completely negative workup. The other was a missed atrial flutter, but nothing changed about their management except also getting a negative workup.

Bottom line: Having cardiology over read ED ECGs results in a change of management in somewhere between 0 and 0.01% of patients (and adds a bunch of false positives).

 

We don’t listen to our own literature (ACLS still doesn’t work)

Sanghavi BS et al. Outcomes After Out-of-Hospital Cardiac Arrest Treated by Basic vs Advanced Life Support. JAMA Intern Med. 2015;175(2):196-204. PMID: 25419698

We already know this, because it has been over a decade since OPALS (in Ontario) proved that ACLS doesn’t work. This is an observational cohort study of American medicare patients with out of hospital cardiac arrest, based on whether they were treated by an ACLS or BLS crew. Survival to hospital discharge was better with BLS (13.1% vs 9.2%). Survival at 90 days was better with BLS (8.0% vs 5.4%).

Bottom line: ACLS doesn’t work. Stop wasting time with IVs and drugs. And most importantly, can we please remove any kind of ACLS training from my hospital credentialing requirements?

 

Related: Less is also more for airway management in cardiac arrest

McMullan J et al. Airway management and out-of-hospital cardiac arrest outcome in the CARES registry. Resuscitation 2014, 85(5):617-622. PMID: 24561079

This is a retrospective registry review of 10,691 out of hospital cardiac arrests that demonstrated that patients that did not have advanced airways placed during the initial resuscitation were more likely to survive to hospital discharge with good neurological outcomes (OR 4.24 95% CI 3.26-5.20). The use of supraglottic airways was associated with worse outcomes than endotracheal intubation. Of course, these are just associations in a very complex scenario with multiple confounders.

Bottom line: Use good technique and provide slow ventilations with a bag valve mask, unless you believe there is a good reason to do something more advanced.

 

Patients don’t understand us

Shif Y et al. What CPR means to surrogate decision makers of ICU patients. Resuscitation 2015 (In print). PMID: 25711518

This is qualitative research on communication and understanding of CPR by surrogate decision makers in the ICU. (I love this stuff, but probably mostly because my master’s was based in qualitative research and communication. Realistically, this study probably just states the obvious.) Less than half of surrogate decision makers identified cardiac arrest as the indication for CPR. Only 8% could identify the major components of CPR (although the technical details probably don’t matter that much.) Mostly importantly, 72% thought that the survival rate post CPR is greater than 75%.

Bottom line: It takes a lot of time, but we really do need to teach our patients about medicine.

 

Ketamine will not make your head explode (although, if my head did explode, I would probably be grateful to be in the K-hole)

Cohen L et al. The effect of ketamine on intracranial and cerebral perfusion pressure and health outcomes: a systematic review. Annals of Emergency Medicine 2015; 65(1):45-51. PMID: 25064742

This systematic review found a total of 10 studies, all in the ICU or OR as they were actually measuring ICPs. Mostly ketamine didn’t change ICP or CPP. In two studies, ICP actually decreased with ketamine. In two studies it did go up, but by 2-4 mmHg, so clinically meaningless. There were no changes in neurological outcomes, ICU length of stay, or mortality.

Bottom line: Ketamine is a wonder drug that can do anything, possibly even solve our boarding crisis, so go ahead and use it whenever you want.

 

Also, tetracaine is not going to melt your eyeballs

Waldman N et al. Topical tetracaine used for 24 h is safe and rated highly effective by patients for the treatment of pain caused by corneal abrasions: a double-blind, randomized clinical trial. Acad Emerg Med 2014; 21:374-382. PMID: 24730399

This is a prospective double blind RCT in which patients with corneal abrasions were allowed to use tetracaine 1% q30min PRN for pain after simple corneal abrasions (versus saline placebo). This is not the first study to look at this, and the dogma is based on a handful of ridiculous case reports. There were no complications (to be fair 116 patient trial is not big enough to be sure it is safe.) It is a weird trial, because pain scores didn’t go down, but patients were more satisfied with their care if they were given tetracaine.

Bottom line: Patients with painful conditions deserve good pain control. If I had a corneal abrasion, you can be sure I would be using a topical anesthetic.

 

One day we may not radiate our patients at all – apparently you can use ultrasound to look for bowel obstruction?

Jang TB etl al. Bedside ultrasonography for the detection of small bowel obstruction in the emergency department. Emerg Med J. 2011;28(8):676-8. PMID: 20732861

A prospective study of 76 patients with suspected SBO, all of who had a CT scan done. Residents were given a 10 training session on using bedside ultrasound to assess for bowel obstruction. The bedside ultrasound had a sensitivity of 91% and a specificity of 84% compared to the CT gold standard. Compare that to abdominal plain films, which had a sensitivity of 46% and a specificity of 67%.

Bottom line: Ultrasound is much better than plain films for the assessment of SBO.

 

Yet another reason not to order urine tox screens

Felton at al. 13-Year-Old Girl With Recurrent, Episodic, Persistent Vomiting: Out of the Pot and Into the Fire. Pediatrics 2015 (Ahead of print). PMID: 25733759

OK, this is only a case report and only gets in because I have an axe to grind. I hate urine toxicology screens and believe they should never be ordered in the ED. But it does raise an interesting tidbit to keep in mind: apparently pantoprozole can cause a false positive urine tox screen for marijuana.

Bottom line: Never rely on a urine tox screen.

 

NPO time irrelevant for procedural sedation

Godwin SA et al. Clinical policy: procedural sedation and analgesia in the emergency department. Ann Emerg Med. 2014;63(2):247-58. PMID: 24438649

As part of the ACEP clinical policy process, they did a systematic review. They found 5 studies that cover thousands of patients, and found no evidence that fasting decreased aspiration or other adverse events. The official policy is “Level B: Do not delay procedural sedation in adults or pediatrics in the ED based on fasting time. Preprocedural fasting for any duration has not demonstrated a reduction in the risk of emesis or aspiration when administering procedural sedation and analgesia.”

Bottom line: Just make sure they actually take the Doritos out of their mouth before starting.

 

GCS 8, just wait

Duncan R and Thakore S. Decreased Glasgow Coma Scale does not mandate endotracheal intubation in the emergency department. J Emerg Med 2009;37(4):451-5. PMID: 19272743

An older paper that came across my desk that I think is worth including because I know practice varies wildly in this regard, and I have debated this point with multiple folks. This is a prospective study of 73 overdose patients with decreased LOC who were watched, not intubated (GCS ranged from 3 to 14). No patient with a GCS under 8 worsened, required intubation, or aspirated.

Bottom line: GCS under 8 shouldn’t be an automatic intubation in tox patients

 

Best way to avoid the pain of an ABG – don’t do one. Second best way: use an insulin needle?

Ibrahim I et al. Arterial Puncture Using Insulin Needle Is Less Painful Than With Standard Needle: A Randomized Crossover Study. Acad Emerg Med 2015 (Ahead of print). PMID: 25731215

Although I don’t think ABGs are very helpful most of the time, you might want to calculate an A-a gradient or something some day. This was a randomized study of healthy volunteers comparing a standard 23 gauge to an insulin needle for arterial stabs. Not surprisingly, both pain and complications were lower with the smaller needle. However, hemolysis went up, so not great if you really want a K – but why do you want to know the arterial K?

Bottom line: If you really feel like doing an ABG, use a smaller needle.

 

Infomercials in the Lancet?

Goldstein JN et al. Four-factor prothrombin complex concentrate versus plasma for rapid vitamin K antagonist reversal in patients needing urgent surgical or invasive interventions: a phase 3b, open-label, non-inferiority, randomised trial. Lancet 2015 (ahead of print). PMID: 25728933

This is an open label RCT of 181 patients comparing PCC (Beriplex) to FFP before an ‘urgent surgery or procedure’. Based on rated ‘effective hemostasis’ being achieved in 90% of the PCC group and 75% of the FFP group, the authors conclude that PCC is superior to FFP. Sadly, this article appears to have been written directly by the drug company (if you read the funding statement), had protocol changes as it went, and relies on reporting of a surrogate end point. Despite all that, the treatments were actually identical. Difference in surgical blood loss between the two groups: 12 ml. Total number of units of blood transfused – identical in both groups.

Bottom line: This trial will be used to push an expensive medication, but it should be interpreted as the opposite: never use PCC just to get someone to surgery.

 

Hepatic encephalopathy is treated with diarrhea (lactulose is not special)

Rahimi RS et al. Lactulose vs polyethylene glycol 3350-electrolyte solution for treatment of overt hepatic encephalopathy: the HELP randomized clinical trial. JAMA Intern Med 2014; 174(11):1727-1733. PMID: 25243839

This is a small RCT comparing PEG 3350 to lactulose for patients with hepatic encephalopathy. PEG 3350 resulted in more rapid resolution of symptoms than lactulose.

Bottom line: PEG 3350 might be better, but certainly isn’t worse than lactulose for the treatment of hepatic encephalpathy.

 

Your kid is allergy prone? Feed him peanuts

Du Toit et al. Randomized trial of peanut consumption in infants at risk for peanut allergy. NEJM 2015; 372:802-813. PMID: 25705822

This is the RCT to show anyone who ever tells you that there some are things we just can’t study. They took 640 children at risk of developing peanut allergy because they already had an egg allergy or severe eczema and randomized them to either eat or not a peanut based snack. The results are relatively astounding. If you didn’t have a positive skin test at the beginning of the study, being exposed to peanuts decreased your chance of developing a peanut allergy by 12% (NNT = 8). If you had a positive skin test at the outset, being exposed to peanut protein decreased your allergy rate by 25% (NNT =4)!

Bottom line: More of a general interest than emergency medicine specific paper. This is strong support for the cleanliness hypothesis of increasing allergies – if you want to avoid allergy, increase antigen exposure in kids.

Cheesy Joke of the Month

I went to a zoo recently, and the only animal there was a dog…

It was a shitzu