# Equipotent Dose and Cost Comparison of Atracurium and Rocuronium in Laboratory Pigs Anesthetized with Propofol

## TL;DR

This study compares the effectiveness and cost of two muscle relaxants, atracurium and rocuronium, in anesthetized laboratory pigs, finding that rocuronium is more cost-effective despite requiring a higher dose.

## Contribution

The study provides species-specific dosing and cost data for neuromuscular blockers in laboratory pigs, highlighting the cost-effectiveness of rocuronium.

## Key findings

- Rocuronium is more cost-effective than atracurium in anesthetized pigs.
- Pigs require higher doses of neuromuscular blockers than other species.
- Atracurium required a lower continuous dose but had a significantly higher cost.

## Abstract

Neuromuscular blockers are often used to achieve muscle relaxation during surgery in laboratory pigs. However, the lack of specific dosing guidelines for this species often leads researchers to rely on data derived from other animal species, with the risk of inaccuracies. In this study, we compared two commonly used muscle relaxants, atracurium and rocuronium, in 12 healthy laboratory pigs anesthetized with propofol. The animals were divided into two groups of six, and each group received one of the two drugs. The dose of each drug was carefully titrated to maintain a stable level of muscle relaxation. We observed that although atracurium required a lower continuous dose than rocuronium, its cost was significantly higher. The starting dose of the two drugs was similar, but rocuronium proved to be less expensive in the Swiss context. Furthermore, the study showed that pigs require higher doses than other species, highlighting the need for dedicated guidelines.

Neuromuscular blocking agents such as atracurium and rocuronium are commonly used during anesthetic procedures in laboratory pigs. However, species-specific dosing guidelines remain limited, leading to reliance on data extrapolated from other species. This prospective, blinded study aimed to determine the equipotent dose for atracurium (A) and rocuronium (R) in laboratory pigs receiving propofol and to compare their cost-effectiveness. Twelve healthy animals were randomly distributed according to the drug administered (n = 6 per group). For both drugs, the infusion rate was adjusted following an up-and-down titration to maintain a train-of-four count between 3 and 4. Group differences were analyzed using the Wilcoxon signed-rank test. The bolus induction dose (mg/kg) was comparable between atracurium (2.3 [1.8–2.6]) and rocuronium (2 [2]), while atracurium was associated with higher costs (CHF/kg: A, 1.122 [0.878–1.366] versus R, 0.208 [0.208–0.208]; p = 0.002725). The maintenance infusion rate (mg/kg/h) was approximately 40% lower for atracurium (2.7 [2.5–2.8]) than for rocuronium (4.5 [4.4–4.5]; p = 0.004922), yet the maintenance cost (CFH/kg/h) remained higher for atracurium (A: 1.30 [1.22–1.37] versus R: 0.47 [0.45–0.47]; p = 0.0043). This study reports higher doses for anesthetized pigs compared to other species and demonstrates that rocuronium offers superior cost-effectiveness compared to atracurium under these experimental conditions.