(715) Diaphragm Dysfunction from Covid-19 Phrenic Neuropathy: Utilization of Diaphragm Pacing for Recovery

PURPOSE: Literature identifies 4.1% patients with an elevated diaphragm post COVID-19 pneumonia secondary to neuropathy. 7% of lung transplantations were performed secondary to COVID-19. Diaphragm pacing(DP) has been shown to help in recovery of phrenic/diaphragm dysfunction (DD) in 86% of patients. We report our experience of DP in phrenic/DD post COVID-19. METHODS: This is a retrospective analysis of prospective non-randomized interventional experiences at a single institution of an FDA approved humanitarian use device under IRB approval. Two intramuscular electrodes were placed in each diaphragm and electrical stimulation was begun immediately post-operatively to facilitate diaphragm strengthening and phrenic nerve recovery. Serial diaphragmatic electromyography (dEMG) through the implanted electrodes, chest radiographs (CXR), and ventilation use identified. RESULTS: All patients implanted with diaphragm pacers from 1/1/2020 to 9/1/22 were reviewed. 5 out of 262 patients were identified with phrenic/DD secondary to COVID-19. None of the patients had elevated diaphragms prior to COVID-19. Average age was 57(range 39-62) with 2 females. Time from COVID-19 to surgery was 6 months (range 1-9 months). One had bilateral phrenic/DD the remainder (4) had unilateral involvement. Two patients were on invasive mechanical ventilation: 1 had complete recovery of phrenic/diaphragms with decannulation of tracheostomy and the other withdrew life support and expired. The three remaining patients had outpatient implantation for unilateral DD; all showing recovery through dEMG analysis and are still utilizing DP. Intra-operative evaluation of the diaphragm and post-operative evaluation with dEMG confirmed all patients had phrenic neuropathy that led to DD. There were no implantation complications or device related morbidity. CONCLUSION: Phrenic nerve dysfunction and DD may contribute to post-acute sequela of COVID-19 leading to breathlessness. DP was safely used in this report and improved recovery of the involved phrenic nerves and diaphragms. Phrenic nerve dysfunction should be identified prior to lung transplant for possible rehabilitation prior to transplant. There is now also the availability of a temporary DP system that can be placed at the time of lung transplant which would allow earlier recognition and therapy for phrenic nerve or diaphragm dysfunction.