Table 4.
Model build comparison
| Model | − 2LL | AIC | Pop pre-oxygenator Bias | Pop pre-oxygenator Imp | Indiv pre-oxygenator Bias | Indiv pre-oxygenator Imp | R2 pre-oxygenator Pop | R2= pre-oxygenator Indiv | R2 post- oxygenator Pop | R2 post- oxygenator Indiv | P-value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Base two-compartment model | 326 | 337 | − 0.43 | 10.62 | − 0.37 | 0.92 | 0.34 | 0.95 | 0.13 | 0.94 | – |
| Base three-compartment model | 219.9 | 235.9 | 3.16 | 73.1 | − 0.01 | 1.7 | 0.52 | 0.98 | 0.51 | 099 | 0.08 |
| Base three-compartment sequestration ECMO model | 188.3 | 206.9 | − 1.5 | 75.23 | 0.07 | 1.27 | 0.57 | 0.99 | 0.57 | 0.99 | 0.014 |
| Three-compartment sequestration ECMO model with Normalized creatinine clearance adjusted CL = CL0 * (CrCL/120) |
187.4 | 206 | 0.52 | 42.17 | 0.17 | 1.31 | 0.8 | 0.99 | 0.83 | 0.99 | * |
| Three-compartment model sequestration ECMO model normalized for creatinine clearance and weight adjusted CL = CL0 * (CrCL/120), V1 = V0 * (TBW/70) |
190.3 | 208.9 | 0.74 | 43.26 | − 0.17 | 1.29 | 0.77 | 0.99 | 0.8 | 0.99 | * |
| Three-compartment sequestration ECMO model normalized ECMO flowrate adjusted K13 = (Q2*FLOWrate/4000)/V1 K31 = (Q2*FLOWrate/4000)/V3 |
183.4 | 202 | − 2.69 | 78.14 | 0.04 | 1.53 | 0.61 | 0.99 | 0.60 | 0.99 | * |
| Final model given objectives of study: Three-compartment sequestration ECMO, CL and V1 adjusted model CL = CL0 * (CrCL/120) V3 = V0 * (TBW/70) K13 = (Q2*FLOWrate/4000)/V3 K31 = (Q2*FLOWrate/4000)/V3 |
190.5 | 209.1 | 1.57 | 47.01 | − 0.12 | 1.30 | 0.76 | 0.99 | 0.78 | 0.99 | * |
Bias and imprecision values for post ECMO post oxygenator not shown
ECMO extracorporeal membrane oxygenation, pre-oxygenator before oxygenation by ECMO, post-oxygenator after oxygenation by ECMO, V1 volume central compartment, compartment, V0 volume term, V3 volume in the ECMO compartment, CL total clearance, CL0clearance term, Q2 intercompartment flow rate 2, K13rate constant to ECMO compartment from central compartment, K31 rate constant to central compartment from ECMO compartment, − 2LLlog-likelihood ratio, AICakaike information criterion, Pop population, indiv individual (i.e., Bayesian)
Model comparison did not produce a significant P-value compared to final model. Final model chosen based off objectives and known clinically relevant covariate adjustments