To the Editor
With the “rise” of super bugs and multi-drug resistant bacteria, our colleagues in infectious disease have had to resort to any number of strategies to treat patients infected with such organisms. One strategy involves multiple drug combinations including several different classes of antibiotics, many of which have independent, and often an additive, impact on QT interval prolongation, with all that entails. Another strategy has been to reach back into the historical archives and reintroduce antibiotics that were either very toxic, had a very limited clinical spectrum of activity, or just didn’t work very well.
I would like to draw the anesthesia community’s attention to one such drug. Colistin, otherwise known as Polymyxin E, is a drug seeing a resurgence in use against multi-drug-resistant Gram negative bacteria, in particular Acinetobacter, E-coli, Klebsiella, and P. aeruginosa. This drug, initially developed in the 1950s, was supplanted by the aminoglycosides because of the concern for significant nephrotoxicity and neurotoxicity associated with Polymyxin E.
Of particular concern to anesthesiologists is the neuromuscular blockade due to non-competitive blockade. This blockade is independent of that caused by our common clinical neuromuscular blocking agents, known to accentuate such blockade, and not reversed by neostigmine.
Recently I was made aware of a case where an individual receiving Colistin to treat a multi-drug-resistant Acinetobacter required surgery and intubation. Unaware of the implication of the antibiotic treatment, the anesthesiologist administered a small, 20-mg dose of rocuronium to facilitate intubation. This resulted in a very deep and prolonged period of neuromuscular blockade, requiring almost 24 hours before measurable evidence of spontaneous recovery of neuromuscular function, and 48 hours of ventilatory support. This patient had received surgical care prior to this without complication, and received surgical care subsequent to this episode without neuromuscular blockers and did well.
I believe it is imperative that members of the anesthesia community who care for patients receiving novel antibiotic drug combinations, particularly Colistin, be very aware of the implications of such therapy, and tailor our anesthetic techniques to account for the risks associated with such therapy.
David Black, MD
Castro Valley, CA