Cold Exposure to the Recurrent Laryngeal Nerve: A Porcine Continuous Intraoperative Neuromonitoring Model Study.

BACKGROUND

Tissue exposure to cold temperatures is common in clinical practice, yet the safety of exposing the recurrent laryngeal nerve (RLN) to cold remains unclear. This study evaluated temperature-dependent effects of cold exposure on RLN function.

METHODS

A porcine continuous intraoperative neuromonitoring (C-IONM) model was used to assess electromyographic (EMG) changes in 16 RLNs exposed to four temperature conditions: room temperature water, cold water, ice water, and ice block. Each exposure lasted 1 min, followed by 20 min of EMG monitoring.

RESULTS

Room temperature and cold water caused no or only mild EMG changes with complete recovery. Ice water induced moderate to severe disturbances with partial reversibility. Ice block exposure produced the most severe effects, including transient loss of signal and incomplete recovery in some nerves.

CONCLUSIONS

Cold exposure below 3°C can induce significant RLN dysfunction. These findings provide evidence that near-freezing temperatures, presumed to be neuroprotective, instead carry a distinct risk of iatrogenic neural injury, underscoring the need for caution in clinical applications.