Diaphragm Pacing in Patients with Spinal Cord Injury: A European Experience

<b><i>Background:</i></b> Patients with high spinal cord injury (SCI) are unable to breathe on their own and require mechanical ventilation (MV). The long-term use of MV is associated with increased morbidity and mortality. In patients with intact phrenic nerve function, patients can be partially or completely removed from MV by directly stimulating the diaphragm motor points with a diaphragm pacing system (DPS). <b><i>Objectives:</i></b> We describe our multicenter European experience using DPS in SCI patients who required MV. <b><i>Methods:</i></b> We conducted a retrospective study of patients who were evaluated for the implantation of DPS. Patients evaluated for DPS who met the prospectively defined criteria of being at least 1 year of age, and having cervical injury resulting in a complete or partial dependency on MV were included. Patients who received DPS implants were followed for up to 1 year for device usage and safety. <b><i>Results:</i></b> Across 3 centers, 47 patients with high SCI were evaluated for DPS, and 34 were implanted. Twenty-one patients had 12 months of follow-up data with a median DPS use of 15 h/day (interquartile range 4, 24). Eight patients (38.1%) achieved complete MV weaning using DPS 24 h/day. Two DPS-related complications were surgical device revision and a wire eruption. No other major complications were associated with DPS use. <b><i>Conclusions:</i></b> Diaphragm pacing represents an attractive alternative stand-alone treatment or adjunctive therapy compared to MV in patients with high SCI. After a period of acclimation, the patients were able to reduce the daily use of MV, and many could be completely removed from MV.

Case Studies in Physiology: Physiological and clinical effects of temporary diaphragm pacing in 2 patients with ventilator-induced diaphragm dysfunction

IntroductionVentilator-induced diaphragm dysfunction (VIDD) is increasingly recognized as an important side-effect of invasive ventilation in critically ill patients and is associated with poor outcomes. Whether patients with VIDD benefit from temporary diaphragm pacing is uncertain.Material and MethodsIntramuscular diaphragmatic electrodes were implanted for temporary stimulation with a pacing device (TransAeris{trade mark, serif} System) in two patients with VIDD. The electrodes were implanted via laparoscopy (first patient), or via bilateral thoracoscopy (second patient). Stimulation parameters were titrated according to tolerance. Diaphragm thickening fraction by ultrasound, maximum inspiratory pressure (Pimax) and diaphragm electromyography (EMGdi) signal analysis were used to monitor the response to diaphragm pacing.ResultsBoth patients tolerated diaphragm pacing. In the first patient improvements in diaphragm excursions were noted once pacing was initiated, and diaphragm thickening fraction did not further deteriorate over time. The diaphragm thickening fraction improved in the second patient, and Pimax as well as EMGdi analysis suggested improved muscle function. This patient could be fully weaned from the ventilator.DiscussionThese case reports present the first experience with temporary diaphragm pacing in critically ill patients with VIDD. Our results should be taken cautiously given the reduced sample size, but provide the proof of concept to put forward the hypothesis that a course of diaphragm pacing may be associated with improved diaphragmatic function. Our findings of the tolerance to the procedure and the beneficial physiological effects are not prove of safety and efficacy, but may set the ground to design and conduct larger studies.