Table 1.
Demographic Data of Simulated Population
| Drug | Ampicillin16,a,b | Gentamicin10,a,c |
|---|---|---|
| Sample size | 34,689 | |
| GA (wk) | 26 (22–27) | |
| BW (kg) | 0.790 (0.400-1.497) | |
| Postnatal age (d) | 1 (1) | |
| PMA (wk) | 26 (22-27) | |
| SCR (mg/dL) | 0.90 (0.05-4.7)d | |
| Volume (L/kg) | 0.32 (0.16-0.60) | 0.39 (0.09-1.28) |
| CL (L/h/kg) | 0.032 (0.007-0.159) | 0.025 (0.006-0.080) |
Abbreviations: BW, birth weight; CL, clearance; GA, gestational age; N/A, not applicable or available; PMA, post-menstrual age; SCR, serum creatinine; WTKG, weight in kg; V, volume of distribution
aNumbers, except for sample size, represent median with range in parentheses.
bAmpicillin model: V = 0.399 * WTKG and CL = 0.078 * WTKG * (0.6/SCR)0.428 * (PMA/37)1.34.
cGentamicin model: CL = (0.00504 + [0.00108*GA]) *BW; median V and CL values with respective ranges for GA < 28 weeks were used.
dAt baseline from start of antibiotic therapy, most of the subjects (82%) had SCR < 1 mg/dL, 16% with 1 to 2 mg/dL, and <1% with >2 mg/dL.