1) You have effective therapies already. 2) There is a total of one (1) study in the literature on SL captopril. It was not a particularly large study, there was NOT a statistically significant difference in the number of patients who got intubated, and while the patients improved faster with captopril, the end result was the same in both groups. Based on this single study with interesting results, I would not say that the evidence exists to suggest it as first line therapy. The hallmark of a good study is its reproducibility! How many studies have you seen in which amazing results were touted but these could not be repeated? There is one (1) study on the effects of a single dose of IV enalapril in just 20 ICU patients who have a S-G catheter in place. There there was no effect of enalapril on cardiac output, but wedge pressure did decrease singificantly. Effects on the blood gases were statistically significant, but of questionable clinical significance. There is no assessment of this drug on the ultimate outcome of the patients. This study involving ICU patients who have already received significant therapy also may have little relevance to what happens in the ED. 3) How do you know the K+ is not 8.5, and the Creatinine 5.5? Would you hestitate to give captopril in this instance? What will you do the first time you give captopril and 30 minutes later get lab results like these back? Am I wrong to worry about this? I cannot find any good studies telling me not to worry about this. 4) What if the pressure plummets to 40? Didn't we have this problem (causing strokes, MIs and death) in rare patients when we gave sublingual nifedipine? 5) How often have therapies that are sensible from a physiologic point of view been proven ultimately harmful? For instance, certain cholesterol-lowering agents were paradoxically found to increase mortality! Calcium-channel blockers were found to increase mortality! Prophylactic lidocaine in acute MI was found to increase mortality! Hyperventilation in head injury is now considered a faux-pas! AND... the converse is often true: therapies that might seem physiologically harmful pan out to be helpful. For instance, b-blockers prolong life even in people with fairly bad ejection fractions. I think that of all the arguments in medicine, ones based on logic or physiology are the weakest because they seem to turn out to be wrong when placed under the heat of a prospective investigation. --"Jonathan A. Handler, M.D."