American ER Doc Gone Walkabout Episode 027
I got another “Pathway” to be used in our ED today – for the management of esophageal obstruction. It ought to be pretty useful, as it defines what the various departmental roles and responsibilities are if medical management fails – i.e. who manages sedation while GI disimpacts via endoscope and what happens next if endoscopy under procedural sedation only fails.
But, I was surprised that the only recommended medical management was IV glucagon. I gave up on that decades ago – it’s never worked for me (except when the patient vomits from the glucagon, and blasts the food bolus out through his eyeballs – if you try this stuff, give it really slow), and in studies, it seems to generally be outperformed by placebo.
Somewhere back in the early 70’s, I learned – and I don’t recall from whom or where – that GTN (glyceryl trinitrite, or NTG aka nitroglycerin for those in the upper half of the globe) worked well for lower esophageal food impactions. My impression over the years is that it does work – probably more than half the time – just standard 0.4 mg sublingual every 5 minutes for 3 doses or until symptoms resolve. I’ve used a glass of water as a chaser – partly, hoping that the weight of the water would encourage passage, but more as a diagnostic test – the patient can tell you if the water passes through the esophagus or not. These folks are often a bit volume depleted – they haven’t been able to eat or drink for a while – that’s why they’ve come to you. If you just give them the GTN cold turkey, they all have syncope, so it’s a nice touch to either warn them that they’ll pass out (makes for a very dramatic resolution of symptoms), or perhaps better, run in a quick saline bolus before the GTN – less dramatic, but perhaps a bit easier on the patient.
Most patients are able to point to the level of impaction – base of the neck for cricopharyngeus muscle level of obstruction, lower sternum for obstruction at the lower esophageal sphincter. One would expect GTN to work at the LES but not at the cricopharyngeus – smooth muscle vs striated muscle, and all that – and that has been true in my experience. I suppose that a trial of a benzo might work at the cricopharyngeus, but I can’t recall having done that.
I’ve used the GTN trick for 40 years or so, and never questioned it, never looked up whether it had beens studied, and now am rather surprised that it appears to in fact have no evidence base whatsoever.
I was curious and did a quick Google search and could find little in the literature, except that David Munter in the Roberts and Hedges “Procedures” book recommends it based upon 2 letters to the editor in the 1980 Annals of Emergency Medicine – now, there’s a real Evidence Based Medicine approach. But, it works, I tell you, it works, I’ve seen it with my own eyes.
Back in the days before flexible endoscopy was readily available, and the surgeons and ENT’s did rigid esophagoscopy, that didn’t happen at night – so, we’d just sedate the hell out of the patient with pethedine (Demerol or meperedine, Yanks) and Valium, put an NG tube down to the level of the obstruction and suck out the secretions to minimize the risk of aspiration to something less than 75%, and wait until daylight. Quite a few actually spontaneously opened before the procedure was performed.
Then there was the deservedly brief popularity of using a CO2 producing agent (“Pop Rocks” were popular) plus voluminous water to “blast” the foreign body through. Unfortunately, where it got blasted to seemed to be not well controlled, and steak in the mediastinum didn’t get digested well.
One other technique that may be apocryphal: A patient with an obstruction was being wheeled to the endoscopy suite, down a sloping ramp, when the transporter lost control of the gurney and it descended the ramp at high speed, crashing into a wall, and popping the offending hot dog out of the patient’s gullet. Being an enterprising fellow who thought quickly, the transporter ran down to the patient an exclaimed: “Wow, you are so lucky, sometimes we have to do that 3 or 4 times before it works.”
Perhaps we should try Mentos and Diet Coke for a somewhat similar effect (YouTube has some entertaining videos of folks blasting foreign substances into their lungs as they mix Mentos and Diet Coke in their mouths – don’t try this at home, or in the ER).
One other note on the Olden Days: We rather jokingly said that if you gave GTN to a patient and they syncoped, that it wasn’t really myocardial ischemia – i.e. syncope from GTN was a powerful predictor of the absence of ischemia. Now, presumably we missed a few RV infarcts by this diagnostic approach. But, perhaps there is some reality to the observation: folks with myocardial ischemia have very high sympathetic tone, and consequent vasoconstriction (and perhaps high filling pressures), and will tolerate and, indeed, benefit from the GTN. Whereas, the non-sick patient with no increase in sympathetic tone, no vasoconstriction, normal filling pressures – he has a much higher chance of hypotension and syncope from the GTN. Medicine was so much more fun when we had no real evidence base to operate from.
So, there you have it, a little history. And, a number of potential clinical study candidates: Mentos and Diet Coke to treat esophageal (OK, sorry, oesophageal) obstruction; evaluation of syncope in response to GTN as a negative predictor for myocardial ischemia: and (this one is actually serious, my apologies) GTN as medical management for lower esophageal obstructing foreign bodies (damn auto-correct keeps changing the spelling of oesophagus – even when I try to spell it correctly in Australian).
Next time: Notes from SAEM 2014
American ER doc