Phrenic Nerve Reconstruction for Effective Surgical Treatment of Diaphragmatic Paralysis.

ABSTRACT: Diaphragmatic paralysis due to phrenic nerve injury may cause orthopnea, exertional dyspnea, and sleep-disordered breathing. Phrenic nerve reconstruction may relieve symptoms and improve respiratory function. A retrospective review of 400 consecutive patients undergoing phrenic nerve reconstruction for diaphragmatic paralysis at 2 tertiary treatment centers was performed between 2007 and 2019. Symptomatic patients were identified, and the diagnosis was confirmed on radiographic evaluations. Assessment parameters included pulmonary spirometry (forced expiratory volume in 1 second and FVC), maximal inspiratory pressure, compound muscle action potentials, diaphragm thickness, chest fluoroscopy, and Short Form 36 Health Survey Questionnaire (SF-36) survey. There were 81 females and 319 males with an average age of 54 years (range, 19-79 years). The mean duration from diagnosis to surgery was 29 months (range, 1-320 months). The most common etiologies were acute or chronic injury (29%), interscalene nerve block (17%), and cardiothoracic surgery (15%). The mean improvements in forced expiratory volume in 1 second and FVC at 1 year were 10% (P < 0.01) and 8% (P < 0.05), respectively. At 2-year follow-up, the corresponding values were 22% (P < 0.05) and 18% (P < 0.05), respectively. Improvement on chest fluoroscopy was demonstrated in 63% and 71% of patients at 1 and 2-year follow-up, respectively. There was a 20% (P < 0.01) improvement in maximal inspiratory pressure, and compound muscle action potentials increased by 82% (P < 0.001). Diaphragm thickness demonstrated a 27% (P < 0.01) increase, and SF-36 revealed a 59% (P < 0.001) improvement in physical functioning. Symptomatic diaphragmatic paralysis should be considered for surgical treatment. Phrenic nerve reconstruction can achieve symptomatic relief and improve respiratory function. Increasing spirometry and improvements on Sniff from 1 to 2 years support incremental recovery with longer follow-up.

Treatment for bilateral diaphragmatic dysfunction using phrenic nerve reconstruction and diaphragm pacemakers.

OBJECTIVES: Bilateral diaphragmatic dysfunction results in severe dyspnoea, usually requiring oxygen therapy and nocturnal ventilatory support. Although treatment options are limited, phrenic nerve reconstruction (PR) offers the opportunity to restore functional activity. This study aims to evaluate combination treatment with PR and placement of a diaphragm pacemaker (DP) compared to DP placement alone in patients with bilateral diaphragmatic dysfunction. METHODS: Patients with bilateral diaphragmatic dysfunction were prospectively enrolled in the following treatment algorithm: Unilateral PR was performed on the more severely impacted side with bilateral DP implantation. Motor amplitudes, ultrasound measurements of diaphragm thickness, maximal inspiratory pressure, forced expiratory volume, forced vital capacity and subjective patient-reported outcomes were obtained for retrospective analysis following completion of the prospective database. RESULTS: Fourteen male patients with bilateral diaphragmatic dysfunction confirmed on chest fluoroscopy and electrodiagnostic testing were included. All 14 patients required nocturnal ventilator support, and 8/14 (57.1%) were oxygen-dependent. All patients reported subjective improvement, and all 8 oxygen-dependent patients were able to discontinue oxygen therapy following treatment. Improvements in maximal inspiratory pressure, forced vital capacity and forced expiratory volume were 68%, 47% and 53%, respectively. There was an average improvement of 180% in motor amplitude and a 50% increase in muscle thickness. Comparison of motor amplitude changes revealed significantly greater functional recovery on the PR + DP side. CONCLUSIONS: PR and simultaneous implantation of a DP may restore functional activity and alleviate symptoms in patients with bilateral diaphragmatic dysfunction. PR plus diaphragm pacing appear to result in greater functional muscle recovery than pacing alone.

Microneurosurgical treatment options in peripheral nerve compression syndromes after chemotherapy and radiation treatment.

Chemotherapy-induced peripheral neuropathy and radiation-induced brachial plexopathy are extremely debilitating conditions which can occur after treatment of malignancy. Unfortunately, the diagnosis can be elusive, and this dilemma is further compounded by the lack of efficacious therapeutics to prevent the onset of neurotoxicity before initiating chemotherapy or radiation or to treat these sequelae after treatment. However, microsurgical nerve decompression can provide these patients with a viable option to treat this complication.

Shoulder Subluxation Pain as a Secondary Indication for Trapezius to Deltoid Transfer.

Brachial plexus injuries can be debilitating. We have observed that manual reduction of the patients' shoulder subluxation improves their pain and have used this as a second reason to perform the trapezius to deltoid muscle transfer beyond motion. The authors report a series of nine patients who all had significant improvement of pain in the shoulder girdle and a decrease in pain medication use after a trapezius to deltoid muscle transfer. All patients were satisfied with the outcomes and stated that they would undergo the procedure again if offered the option. The rate of major complications was low. The aim is not to describe a new technique, but to elevate a secondary indication to a primary for the trapezius to deltoid transfer beyond improving shoulder function: pain relief from chronic shoulder subluxation.

Long-Term Follow-Up after Phrenic Nerve Reconstruction for Diaphragmatic Paralysis: A Review of 180 Patients.

Background Phrenic nerve reconstruction has been evaluated as a method of restoring functional activity and may be an effective alternative to diaphragm plication. Longer follow-up and a larger cohort for analysis are necessary to confirm the efficacy of this procedure for diaphragmatic paralysis. Methods A total of 180 patients treated with phrenic nerve reconstruction for chronic diaphragmatic paralysis were followed for a median 2.7 years. Assessment parameters included: 36-Item Short Form Health Survey (SF-36) physical functioning survey, spirometry, chest fluoroscopy, electrodiagnostic evaluation, a five-item questionnaire to assess specific functional issues, and overall patient-reported outcome. Results Overall, 134 males and 46 females with an average age of 56 years (range: 10-79 years) were treated. Mean baseline percent predicted values for forced expiratory volume in 1 second, forced vital capacity, vital capacity, and total lung capacity, were 61, 63, 67, and 75%, respectively. The corresponding percent improvements in percent predicted values were: 11, 6, 9, and 13% (p ≤ 0.01; ≤ 0.01; ≤ 0.05; ≤ 0.01). Mean preoperative SF-36 physical functioning survey scores were 39%, and an improvement to 65% was demonstrated following surgery (p ≤ 0.0001). Nerve conduction latency, improved by an average 23% (p ≤ 0.005), and there was a corresponding 125% increase in diaphragm motor amplitude (p ≤ 0.0001). A total of 89% of patients reported an overall improvement in breathing function. Conclusion Long-term assessment of phrenic nerve reconstruction for diaphragmatic paralysis indicates functional correction and symptomatic relief.

Diaphragmatic reinnervation in ventilator-dependent patients with cervical spinal cord injury and concomitant phrenic nerve lesions using simultaneous nerve transfers and implantable neurostimulators.

BACKGROUND: Patients who are ventilator dependent as a result of combined cervical spinal cord injury and phrenic nerve lesions are generally considered to be unsuitable candidates for diaphragmatic pacing due to loss of phrenic nerve integrity and denervation of the diaphragm. There is limited data regarding efficacy of simultaneous nerve transfers and diaphragmatic pacemakers in the treatment of this patient population. METHODS: A retrospective review was conducted of 14 consecutive patients with combined lesions of the cervical spinal cord and phrenic nerves, and with complete ventilator dependence, who were treated with simultaneous microsurgical nerve transfer and implantation of diaphragmatic pacemakers. Parameters of interest included time to recovery of diaphragm electromyographic activity, average time pacing without the ventilator, and percent reduction in ventilator dependence. RESULTS: Recovery of diaphragm electromyographic activity was demonstrated in 13 of 14 (93%) patients. Eight of these 13 (62%) patients achieved sustainable periods (> 1 h/d) of ventilator weaning (mean = 10 h/d [n = 8]). Two patients recovered voluntary control of diaphragmatic activity and regained the capacity for spontaneous respiration. The one patient who did not exhibit diaphragmatic reinnervation remains within 12 months of initial treatment. Surgical intervention resulted in a 25% reduction (p < 0.05) in ventilator dependency. CONCLUSION: We have demonstrated that simultaneous nerve transfers and pacemaker implantation can result in reinnervation of the diaphragm and lead to successful ventilator weaning. Our favorable outcomes support consideration of this surgical method for appropriate patients who would otherwise have no alternative therapy to achieve sustained periods of ventilator independence.

Functional restoration of diaphragmatic paralysis: an evaluation of phrenic nerve reconstruction.

BACKGROUND: Unilateral diaphragmatic paralysis causes respiratory deficits and can occur after iatrogenic or traumatic phrenic nerve injury in the neck or chest. Patients are evaluated using spirometry and imaging studies; however, phrenic nerve conduction studies and electromyography are not widely available or considered; thus, the degree of dysfunction is often unknown. Treatment has been limited to diaphragmatic plication. Phrenic nerve operations to restore diaphragmatic function may broaden therapeutic options. METHODS: An interventional study of 92 patients with symptomatic diaphragmatic paralysis assigned 68 (based on their clinical condition) to phrenic nerve surgical intervention (PS), 24 to nonsurgical (NS) care, and evaluated a third group of 68 patients (derived from literature review) treated with diaphragmatic plication (DP). Variables for assessment included spirometry, the Short-Form 36-Item survey, electrodiagnostics, and complications. RESULTS: In the PS group, there was an average 13% improvement in forced expiratory volume in 1 second (p < 0.0001) and 14% improvement in forced vital capacity (p < 0.0001), and there was corresponding 17% (p < 0.0001) and 16% (p < 0.0001) improvement in the DP cohort. In the PS and DP groups, the average postoperative values were 71% for forced expiratory volume in 1 second and 73% for forced vital capacity. The PS group demonstrated an average 28% (p < 0.01) improvement in Short-Form 36-Item survey reporting. Electrodiagnostic testing in the PS group revealed a mean 69% (p < 0.05) improvement in conduction latency and a 37% (p < 0.0001) increase in motor amplitude. In the NS group, there was no significant change in Short-Form 36-Item survey or spirometry values. CONCLUSIONS: Phrenic nerve operations for functional restoration of the paralyzed diaphragm should be part of the standard treatment algorithm in the management of symptomatic patients with this condition. Assessment of neuromuscular dysfunction can aid in determining the most effective therapy.

The use of bone anchors for autologous flap fixation in perineal reconstruction: a case report.

The purpose of this case report is to demonstrate the use of bone anchors with an autologous flap in perineal reconstruction. This technique has not been reported before. A 64-year-old female presented to our office with a chief complaint of perineal hernia 1.5 years after abdominoperineal resection. She had a history of recurrent rectal cancer for which she received chemotherapy, radiation and surgery. To repair the hernia, a standard vertical rectus abdominismyocutaneous was harvested and de-epithelialized. It was secured into place in the pelvis utilizing several bone anchors. Mesh was used to repair the donor site defect. At 18 month follow-up, there was good healing of all the wounds and no recurrence of the hernia. She was pain free and able to resume her activities of daily living. Bone anchor fixation is a viable technique for fixation of autologous flaps in perineal reconstruction.

Diaphragm paralysis caused by transverse cervical artery compression of the phrenic nerve: the Red Cross syndrome.

BACKGROUND: The etiology of diaphragm paralysis is often elusive unless an iatrogenic or traumatic injury to the phrenic nerve can be clearly implicated. Until recently, there has been little interest in the pathophysiology of diaphragm paralysis since few treatment options existed. METHODS: We present three cases of symptomatic diaphragm paralysis in which a clear clinico-pathologic diagnosis could be identified, specifically a vascular compression of the phrenic nerve in the neck caused by a tortuous or adherent transverse cervical artery. RESULTS: In two patients the vascular compression followed a preceding traction injury, whereas in one patient an inter-scalene nerve block had been performed. Following vascular decompression, all three patients regained diaphragmatic motion on fluoroscopic chest radiographs, and experienced a resolution of respiratory symptoms. CONCLUSION: We suggest that vascular compression of the phrenic nerve in the neck may occur following traumatic or iatrogenic injuries, and result in symptomatic diaphragm paralysis.

Nerve allograft transplantation for functional restoration of the upper extremity: case series.

BACKGROUND: Major trauma to the spinal cord or upper extremity often results in severe sensory and motor disturbances from injuries to the brachial plexus and its insertion into the spinal cord. Functional restoration with nerve grafting neurotization and tendon transfers is the mainstay of treatment. Results may be incomplete due to a limited supply of autologous material for nerve grafts. The factors deemed most integral for success are early surgical intervention, reconstruction of all levels of injury, and maximization of the number of axonal conduits per nerve repair. OBJECTIVE: To report the second series of nerve allograft transplantation using cadaveric nerve graft and our experience with living-related nerve transplants. PARTICIPANTS: Eight patients, seven men and one woman, average age 23 years (range 18-34), with multi-level brachial plexus injuries were selected for transplantation using either cadaveric allografts or living-related donors. METHODS: Grafts were harvested and preserved in the University of Wisconsin Cold Storage Solution at 5 degrees C for up to 7 days. The immunosuppressive protocol was initiated at the time of surgery and was discontinued at approximately 1 year, or when signs of regeneration were evident. Parameters for assessment included mechanism of injury, interval between injury and treatment, level(s) of deficit, post-operative return of function, pain relief, need for revision surgery, complications, and improvement in quality of life. RESULTS: Surgery was performed using living-related donor grafts in six patients, and cadaveric grafts in two patients. Immunosuppression was tolerated for the duration of treatment in all but one patient in whom early termination occurred due to non-compliance. There were no cases of graft rejection as of most recent followup. Seven patients showed signs of regeneration, demonstrated by return of sensory and motor function and/or a migrating Tinel's sign. One patient was non-compliant with the post-operative regimen and experienced minimal return of function despite a reduction in pain. CONCLUSIONS: Despite the small number of subjects, it appears that nerve allograft transplantation may be performed safely, permitting non-prioritized repair of long-segment peripheral nerve defects and maximizing the number of axonal conduits per nerve repair. For patients with long, multi-level brachial plexus injuries or combined upper and lower extremity nerve deficits, the use of nerve allograft allows a more complete repair that may translate into greater functional restoration than autografting alone.

Reinnervation of the paralyzed diaphragm: application of nerve surgery techniques following unilateral phrenic nerve injury.

BACKGROUND: Unilateral phrenic nerve injury often results in symptomatic hemidiaphragm paralysis, and currently few treatment options exist. Reported etiologies include cardiac surgery, neck surgery, chiropractic manipulation, and interscalene nerve blocks. Although diaphragmatic plication has been an option for treatment, the ideal treatment would be restoration of function to the paralyzed hemidiaphragm. The application of peripheral nerve surgery techniques for phrenic nerve injuries has not been adequately evaluated. METHODS: Twelve patients presenting with long-term, symptomatic, unilateral phrenic nerve injuries following surgery, chiropractic manipulation, trauma, or anesthetic blocks underwent a comprehensive evaluation, including radiographic and electrophysiologic assessments. Surgical treatment was offered following a minimum of 6 months of conservative management. Operative planning was based on preoperative and intraoperative testing using one or more established nerve reconstruction techniques (neurolysis, interpositional grafting, or neurotization). RESULTS: Measures of postoperative improvement included pulmonary function testing, fluoroscopic sniff testing, and a standardized quality-of-life survey, from which it was determined that eight of nine patients who could be completely evaluated experienced improvements in diaphragmatic function. CONCLUSIONS: Based on the favorable results in this small series, we suggest expanding nerve reconstruction techniques to phrenic nerve injury treatment and propose an algorithm for treatment of unilateral phrenic nerve injury that may expand the current limitations in therapy.