To the Editor:
In their case study of negative-pressure pulmonary edema (NPPE), Krodel et al .1repeat the oft-cited idea that diuretics should be included in the therapies for this condition. They refer to using furosemide in the postanesthesia care unit for NPPE, which occurred as a result of laryngospasm on emergence. The authors do acknowledge that diuretics are not universally recommended for NPPE, noting that they “are often administered, but their use is controversial and may even be unnecessary.” However, we are surprised that expert opinion continues to afford even a qualified role to diuretics. To our knowledge, there has never been any evidence for doing so. Beyond the knee-jerk association between pulmonary edema and loop diuretic administration, we cannot imagine why NPPE should routinely or even occasionally be managed with diuretics. Indeed, the careful elucidation of pathophysiologic features in this review should demonstrate that neither intravascular nor total body volume is increased in those with NPPE; these volumes, in contrast, may be significantly decreased. The sudden shift of fluid into the pulmonary interstitium has little in common with other scenarios in which diuresis is helpful in reducing excess total body water. In those with NPPE, diuretic administration may be unnecessary and harmful, particularly in patients who are older and less able to compensate for hypovolemia than the 25-yr-old otherwise healthy man who is described. Indeed, anecdotal experience at our institution has shown that furosemide administration to patients with NPPE can result in hypovolemic shock requiring fluid resuscitation.
*Stanford University Medical Center, Stanford, California. firstname.lastname@example.org