RETROSPECTIVE PHARMACOECONOMIC EVALUATION OF DOSING VECURONIUM BY PERIPHERAL-NERVE STIMULATION VERSUS STANDARD CLINICAL-ASSESSMENT IN CRITICALLY-ILL PATIENTS

Adjusting the dosage of vecuronium by peripheral nerve stimulation ver sus standard clinical dosing in critically ill. patients reduces drug requirements to maintain a desired depth of paralysis and, on average, produces faster recovery of neuromuscular function. We retrospectivel y analyzed the health and economic outcomes of using train-of-four (TO F) end points by peripheral nerve stimulation in dosing neuromuscular blocking agents during continuous infusion in a medical intensive care unit (ICU). A decision-analytic model was used to calculate outcomes and costs of treatment using and not using TOF end points of dosing ve curonium. Data from our TOF trial provided the difference in neuromusc ular and functional recovery time. Charges billed by the Patient Finan cial Services Department were used to determine hourly costs of ICU st ay for recovery from neuromuscular blockade using costs:charges ratios estimated from a sample of 20 patients. The cost of vecuronium was de termined using the hospital acquisition cost and the actual number of milligrams of drug given to each patient in the TOF trial. The cost of performing one TOF event was determined by timing six events performe d by six pharmacists, and randomly selecting 60% of these to calculate a mean time/TOF event. The economic impact of dosing by TOF was deter mined by calculating the cost savings/patient dosed by TOF compared wi th those who had doses individualized by standard clinical assessment. One-way and multiway sensitivity analyses were performed to assess mo del uncertainty. The mean drug cost was $286 in the TOF group versus $ 580 in the standard dosing group. With a mean time/TOF assessment of 5 .8 +/- 1.6 minutes, each episode cost $2.92 for a total TOF cost/patie nt of $23. At $54/hour of recovery time in the ICU, the estimated cost of ICU care for the TOF group was $34,214 versus $118,681 for the sta ndard group. The estimated costs/patient were $459 and $1197, respecti vely, for a total cost savings/patient of $738. Sensitivity analyses s howed the model to be robust. Estimated annual savings of $146,103 are projected by using TOF to individualize vecuronium doses in patients in the ICU. Individualizing vecuronium doses to TOF end points has bot h therapeutic and economic advantages. When considering costs of drug, TOF monitoring, and ICU, the total cost/patient was 40% of that in th e control group.