Low cefpirome levels during twice daily dosing in critically ill septic patients: pharmacokinetic modelling calls for more frequent dosing.
OBJECTIVE
To measure plasma levels and pharmacokinetics of cefpirome in critically ill septic patients with normal renal function. To use the pharmacokinetic model to simulate alternate dosing regimens and identify those that predict sustained levels.


METHODS
A prospective, open-label, descriptive study in a 22-bed, multidisciplinary, adult ICU in a university-affiliated, tertiary referral hospital.


METHODS
Twelve adults with normal renal function on enrollment and with suspected or documented sepsis in whom cefpirome was judged to be the appropriate therapy by the managing clinician.


METHODS
Cefpirome 2 g was infused intravenously over 3 min every 12 h. Timed blood samples were taken prior to and during two dosing intervals. Urine was collected for creatinine clearance determination.


RESULTS
Two patients were non-evaluable due to renal dysfunction post-enrollment. The median cefpirome trough level was 1.1 mg/l (range 0.5-8.1 mg/l) after the initial dose and 1.4 mg/l (range < 0.5-15.9 mg/l) at 'steady state'. The volumes of distribution and elimination half-lives were greater and more variable than in healthy volunteers. Pharmacokinetic simulation predicted that more frequent bolus dosing, increased doses and continuous infusions would result in concentrations greater than 4 mg/l for over 60% of the dosing interval for all patients.


CONCLUSIONS
Cefpirome 2 g twice daily produced low plasma troughs in a number of patients. Our data suggest that this drug regimen may be inadequate for successful treatment of difficult-to-treat infections in critically ill patients with normal renal function.
Lipman
J
J
Royal Brisbane Hospital, Herston 4029, Brisbane, Queensland, Australia. j.lipman@mailbox.uq.edu.au
Wallis
S C
SC
Rickard
C M
CM
Fraenkel
D
D
D018806:APACHE; D000328:Adult; D000368:Aged; D019540:Area Under Curve; D002511:Cephalosporins / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D016638:Critical Illness; D005260:Female; D006207:Half-Life; D006801:Humans; D007262:Infusions, Intravenous; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D018805:Sepsis / Q000188:drug therapy*; D016896:Treatment Outcome; D000097572:Cefpirome
D002511:Cephalosporins; D000097572:Cefpirome