Reinnervation of the diaphragm by nerve transfer from the inferior laryngeal nerve to the phrenic nerve in ventilator-dependent tetraplegic patients with C3–5 damage

Abstract

The aim of this study was to evaluate the feasibility of unilateral diaphragmatic reinnervation in human by the inferior laryngeal nerve. This pilot study included chronically ventilated tetraplegic patients with destruction of phrenic nerve motoneurons. Five patients were included. They all had high-level of tetraplegia, with phrenic nerve motoneuron destruction. They were highly dependent of ventilation, without any possible weaning. They did not have other chronic pathology especially laryngeal disease. They all had diaphragmatic explorations to diagnose the destruction of the motoneurons of the phrenic nerves and nasoendoscopy to be sure that they did not have laryngeal or pharyngeal disease. Then, surgical anastomosis of the right phrenic nerve was performed with the inferior laryngeal nerve, by a cervical approach. A laryngeal reinnervation was performed at the same time, using the ansa hypoglossi. One patient was excluded because of functional phrenic nerve and one patient died 6 months after the surgery of a cardiac arrest. The remaining three patients were evaluated after the anastomosis every 6 months. They did not present any swallowing of voice alterations. In those three patients, the diaphragmatic explorations showed that there was a recovery of the diaphragmatic EMG of the right and left hemidiaphragms after one year. Two patients had surgical diaphragmatic explorations for diaphragmatic pacing 18–24 months after the reinnervation with excellent results. In conclusion, this study demonstrated that diaphragmatic reinnervation by the inferior laryngeal nerve is effective, without any voice or swallowing complication.