Purpose: This study was to evaluate the effects of a set of predetermined intravenous (IV) batching schedules on IV waste, in terms of dose, volume, and cost, for a children hospital. The goal was to determine the best IV batching schedule which would result in the least IV waste for the sample hospital.
Methods: A computer simulation approach which mimicked the dynamic system of an IV operation was applied. The simulation models were based on an IV operation of a 423-bed children’s hospital. The IV room, a 24-hour per day operation prepared daily cart exchanges for IV batch doses. The starting preparation time for batch orders was 03:00 (3 AM) and cart exchange at 16:00 (4 PM). There is no reuse police for IV doses after dispatching from the IV room. An IV robot for compounded the most frequently used IV drugs for the batch doses. The IV orders between February 2010 and April 2010 were utilized to determine the input parameters and attributes, e.g., order arrival patterns, type of IV order, number of batch doses, administration time, probability of the dose being discontinued, etc., for the simulation models. A simulation model based on the existing operations was developed and validated. In addition, 12 other simulation models with different starting preparation times and delivery times were derived from the validated baseline model. These IV batching schedules were determined by analyzing the time at which IV orders were created and discontinued. The four once per day IV batching schedules were: (preparation starting time at [03:00], [12:00], [21:00], [14:00]. The six twice per day schedules were: preparation starting times at [12:00 & 24:00], [04:00 & 16:00], [02:00 & 14:00], [04:00 & 12:00],[ 12:00 & 20:00], [14:00 & 22:00],The two three times per day schedules were: preparation times at [04:00, 12:00, & 20:00], and [02:00, 12:00, & 16:00]. Delivery was scheduled two hours after batch initiation. A time study was conducted to quantify the IV admixture time units which were incorporated into the simulation models. Seven hundred and twenty replications, which represent two years IV operation, were simulated for each IV batching schedule.
Results: The simulation output showed the monthly data: (1) for the existing IV operation – 1,631 discontinued orders, 4,015 wasted doses, $18,736 wasted cost, and 93,820 mL of wasted volume, and (2) for the twelve batching schedules – number of discontinued orders ranged from 1,612 to 1,648, wasted doses ranged from 783 to 2,108, wasted costs ranged from $3,548 to $9,909, and wasted volumes ranged from 17,560 mL to 48,087 ml. With the consideration of re-staffing, the results indicated that the IV batching schedule of [04:00, 12:00, & 20:00] was the best choice by reducing 3,206 wasted doses, generating savings of $14,932, and decreasing wasted volume in 75,347 mL, monthly.
Discussion: This study demonstrated the potential for using computer simulation approach to evaluate alternative IV batching schedules to determine the schedule with the least waste and the most cost-savings.