# Sugammadex and Acceleromyography Used During a Lensectomy in a Sea Lion (Zalophus californianus)

## TL;DR

This paper describes the first use of sugammadex and acceleromyography in a sea lion during eye surgery, showing these techniques can safely improve anesthesia and recovery.

## Contribution

The first documented use of sugammadex and acceleromyography in a California sea lion for neuromuscular monitoring and reversal.

## Key findings

- Sugammadex reversed neuromuscular block in a sea lion within 90 seconds.
- Acceleromyography provided objective neuromuscular monitoring during surgery.
- The techniques proved feasible and safe for use in pinnipeds.

## Abstract

Eye surgery is a relatively common procedure in older sea lions in captivity. In this case, a sea lion underwent intraocular surgery to remove a bilateral cataract. A neuromuscular blocking agent (rocuronium) was given to guarantee a central eye position during surgery, and at the end of surgery, a reversal agent (sugammadex) was used for the first time in this species to quickly reverse the neuromuscular block (NMB), allowing for a controlled and prompt recovery. To guide the NMB, a monitoring modality (acceleromyography) was used to measure the depth of the NMB and ensure precise timing of drug administration. This technique has not been described in marine mammals yet. The sea lion recovered without complications. This report documents the first use of two veterinary techniques—acceleromyography to monitor muscle relaxation and sugammadex to reverse it—in a California sea lion. These methods proved feasible and safe, and they show potential to improve anesthesia safety, recovery, and overall welfare in pinnipeds undergoing medical procedures.

Neuromuscular blocking agents (NMBAs) are essential in intraocular surgeries to improve surgical conditions and ensure optimal ventilation. However, residual blockade can pose significant risks, particularly in pinnipeds due to their unique diving physiology. This case report describes the use of sugammadex for reversing rocuronium and AMG for monitoring neuromuscular block (NMB) in a California sea lion undergoing lensectomy. The objective is to evaluate the feasibility and safety of sugammadex for reversal of rocuronium-induced neuromuscular blockade and acceleromyography (AMG) for monitoring neuromuscular function in pinnipeds, with the goal of improving anesthetic management and recovery. Rocuronium (0.3 mg/kg IV) was used to achieve complete NMB, and an additional 0.1 mg/kg IV was administered to prolong the block. Sugammadex (1 mg/kg IV) reversed the NMB, with recovery within 90 s. Neuromuscular function was monitored using AMG, with the ulnar nerve of the foreflipper as the stimulation site. AMG allowed for an objective assessment of neuromuscular function, ensuring accurate titration of the NMBA and reversal agent. This is the first report documenting the use of sugammadex for the reversal of rocuronium and AMG for neuromuscular monitoring in a sea lion. This successful application highlights the potential of these techniques to improve anesthesia protocols, patient safety, and welfare in marine mammal medicine.