Does once-daily dosing of aminoglycosides affect neuromuscular function?
OBJECTIVE
Aminoglycosides have been reported to produce a curare-like neuromuscular blockade in animals at serum concentrations higher than those obtained with traditional dosing (1-2 mg/kg every 8 h) in humans. Aminoglycoside-induced neuromuscular blockade is rarely, if ever, seen in humans with traditional dosing. The recent adoption of once-daily dosing of aminoglycosides has raised concerns about increased potential for this adverse effect because higher serum concentrations are produced. The objective of this study was to determine if once-daily dosing of aminoglycosides inhibits respiratory muscle function.


METHODS
Nine mechanically ventilated ICU patients on once-daily dosing of gentamicin 6 mg/kg/day were assessed for respiratory muscle strength by measuring maximum inspiratory pressure (MIP). MIP is a measurement of the maximal negative pressure generated by repeated inhalations against an occluded airway over 20 s. This was measured within 1 hour before (MIPpre) and within 1 hour after each aminoglycoside dose (MIPpost).


RESULTS
Mean values for MIPpre and MIPpost were -26.7 cm H2O and -26.5 cm H2O, respectively. The mean difference between MIPpre and MIPpost was -0.2 cm H2O, which was not statistically significant (P > 0.05).


CONCLUSIONS
The effect of gentamicin (6 mg/kg/day) on respiratory muscle function was not statistically, nor clinically significant, and weaning from mechanical ventilation does not seem to be inhibited by once-daily dosing of aminoglycosides as detectable by measurement of MIP.
Wong
J
J
Pharmacy Department, St Paul's Hospital, Vancouver, British Columbia, Canada.
Brown
G
G
D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology; D004334:Drug Administration Schedule; D005260:Female; D005839:Gentamicins / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology; D006801:Humans; D008297:Male; D008875:Middle Aged; D019148:Neuromuscular Blockade; D012121:Respiration, Artificial; D012132:Respiratory Muscles / Q000187:drug effects*; D015300:Ventilator Weaning
D000900:Anti-Bacterial Agents; D005839:Gentamicins