Factors affecting gentamicin pharmacokinetics in septic patients.
BACKGROUND
This prospective, comparative study was designed to estimate the volume of distribution (Vd) and elimination rate constant (K(e)) of gentamicin and to determine the clinical factors affecting the pharmacokinetics of gentamicin in different stages of sepsis.


METHODS
Seventy-seven critically ill patients treated with gentamicin for gram-negative sepsis were included. These septic patients were divided into hyperdynamic septic and hypodynamic septic groups according to cardiac index. Twenty-seven patients who received postoperative prophylactic gentamicin were recruited as controls.


RESULTS
Fifty-two patients in the hyperdynamic septic group had a significantly larger Vd than those in the hypodynamic septic and control groups. The Vd was correlated significantly with both Acute Physiological Score (APS) (r=0.340, P<0.01) and cardiac index (r=0.394, P<0.01). The K(e) of gentamicin correlated significantly with both blood urea nitrogen (BUN) (r= 0.565, P<0.01) and serum creatinine level (r=0.563, P<0.01).


CONCLUSIONS
The increased Vd in the septic patients was related to the severity of illness and magnitude of cardiac output. The K(e) of gentamicin was correlated with the serum creatinine level.
Tang
G J
GJ
Department of Anesthesiology and Critical Care, Veterans General Hospital-Taipei and National Yang-Ming University, Taiwan, ROC.
Tang
J J
JJ
Lin
B S
BS
Kong
C W
CW
Lee
T Y
TY
D018806:APACHE; D000368:Aged; D000704:Analysis of Variance; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics* / Q000627:therapeutic use; D019072:Antibiotic Prophylaxis; D001806:Blood Urea Nitrogen; D002302:Cardiac Output / Q000502:physiology; D003404:Creatinine / Q000097:blood; D016638:Critical Illness; D005260:Female; D005839:Gentamicins / Q000493:pharmacokinetics* / Q000627:therapeutic use; D016905:Gram-Negative Bacterial Infections / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D016014:Linear Models; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D011182:Postoperative Care; D011446:Prospective Studies; D018805:Sepsis / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D012720:Severity of Illness Index; D014018:Tissue Distribution
D000900:Anti-Bacterial Agents; D005839:Gentamicins; D003404:Creatinine