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Multidisciplinary Respiratory Medicine Jan 2020Bilateral paralysis of the diaphragm may be an idiopathic clinical condition or associated with several diseases such as trauma, surgery, viral infections, neurologic...
INTRODUCTION
Bilateral paralysis of the diaphragm may be an idiopathic clinical condition or associated with several diseases such as trauma, surgery, viral infections, neurologic disorders. The diaphragm is the main respiratory muscle. It is a cupoliform muscle-tendon structure, innervated bilaterally by phrenic nerve, which originates from C3-C5 nerve roots. Diaphragmatic paralysis is a clinical disorder that generates hypoventilation and basal pulmonary atelectasis, predisposing to hypercapnic respiratory failure. The clinic manifestations mimic cardio-respiratory pathologies, therefore often misdiagnosticated.
CASE PRESENTATION
A 55-year-old man with a previous C6-7 traumatic fracture, referred multiple accesses to the emergency room for acute nocturnal dyspnoea, treated with antibiotic therapy, diuretic therapy and long-term oxygen therapy, without beneficial effects. He referred to our pulmonary clinic for evaluation of persistent and worsening orthopnoea due to unknown cause for about 2 years. Clinical examination, respiratory functional tests and diaphragm ultrasound revealed a strong suspicion of diaphragmatic deficit, confirmed by electromyography.
CONCLUSIONS
The patient accesses to the emergency room numerous times and the clinical frame have been always oriented towards a cardio-respiratory origin. From the onset of the symptom to the respiratory evaluation, about 2.5 years have passed. The manifestation of clear orthopnoea has addressed the functional respiratory study towards a more thorough diaphragmatic evaluation assessed by ultrasound.
PubMed: 32269773
DOI: 10.4081/mrm.2020.415 -
Interactive Cardiovascular and Thoracic... May 2021Bilateral diaphragmatic dysfunction results in severe dyspnoea, usually requiring oxygen therapy and nocturnal ventilatory support. Although treatment options are...
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.
Topics: Diaphragm; Humans; Male; Phrenic Nerve; Respiratory Paralysis; Retrospective Studies
PubMed: 33432336
DOI: 10.1093/icvts/ivaa324 -
Journal of Integrative Neuroscience Sep 2019Preinspiratory discharge manifests in the neuronal recordings of the pre-Bötzinger complex, parafacial respiratory group, retrotrapezoid nucleus, and Kölliker-Fuse... (Review)
Review
Preinspiratory discharge manifests in the neuronal recordings of the pre-Bötzinger complex, parafacial respiratory group, retrotrapezoid nucleus, and Kölliker-Fuse nucleus, as well as the efferent neural discharge of respiratory-related nerves innervating upper airway musculature. This neural component of triphasic eupnea contemporaneously contributes to the genesis of native and originate respiratory rhythmic activity, as well as the preinspiratory component of efferent neural respiratory discharges. In the course of our investigations evaluating hypoglossal discharge in response to asphyxia, we noted a curious pattern of neural respiratory recovery following postasphyxia resuscitation in hypoglossal, vagal, and phrenic neurograms in unanesthetized decerebrate rats. Specifically, we observed a gradual return of a pseudobiphasic eupnea characterized by initial transition bursts followed by robust eupneic bursts with dynamics inclusive of a gradually and progressively increasing duration of the hypoglossal eupneic bursts and duration and amplitude of the preinspiratory component of these bursts, as well as progressively lengthening expiratory interval between these bursts in the phrenic nerve discharge. This was followed by conversion to regular triphasic eupnea. We discuss our extrapolations based on these findings regarding eupneic respiratory central pattern generation and mechanisms contributing to the genesis of preinspiratory activity in hypoglossal discharge.
Topics: Animals; Central Pattern Generators; Humans; Hypoglossal Nerve; Respiration
PubMed: 31601082
DOI: 10.31083/j.jin.2019.03.189 -
Journal of Thoracic Disease Aug 2022The objective of this study was to assess the feasibility and safety of a novel, removable, surgically implanted, temporary neurostimulation approach involving the...
BACKGROUND
The objective of this study was to assess the feasibility and safety of a novel, removable, surgically implanted, temporary neurostimulation approach involving the distal portion of the phrenic nerve.
METHODS
Temporary phrenic nerve pacing electrodes were implanted surgically using an ovine model (4 animals). The primary endpoint was the ability to successfully match the animal's minute-ventilation upon implantation of both phrenic nerve pacers on day 1. Secondary endpoints were successful phrenic neurostimulation by both electrodes 15 and 30 days after initial implantation. We also assessed safe removal of the electrodes at 15 and 30 days after implementation.
RESULTS
In 3 of 4 animals, electrodes were successfully implanted in both right and left phrenic nerves. On day 1, median ventilation-minute induced by neurostimulation was not significantly different from baseline ventilation-minute [4.9 L·min (4.4-5.5) 4.4 L·min (4.3-5.2); P=0.4] after 15 minutes. Neurostimulation was still possible 15 and 30 days after implementation in all left side phrenic nerves. On the right side, stimulation was possible at all times in 1 animal but not in the remaining 3 animals for at least one time point, possibly due to lead displacement. Analysis of pathology after percutaneous electrode removal showed integrity of the distal portion of all phrenic nerves.
CONCLUSIONS
Efficient temporary neurostimulation through the distal portion of the phrenic nerve was possible at baseline. The main complication was the displacement of electrodes on the right phrenic nerve on two occasions, which was due to the anatomy of the ovine model. It compromised diaphragm pacing on day 15 and day 30. The electrodes could be safely removed percutaneously without damage to the phrenic nerves.
PubMed: 36071760
DOI: 10.21037/jtd-21-1944 -
Artificial Organs Oct 2022Diaphragm muscle atrophy during mechanical ventilation begins within 24 h and progresses rapidly with significant clinical consequences. Electrical stimulation of the...
BACKGROUND
Diaphragm muscle atrophy during mechanical ventilation begins within 24 h and progresses rapidly with significant clinical consequences. Electrical stimulation of the phrenic nerves using invasive electrodes has shown promise in maintaining diaphragm condition by inducing intermittent diaphragm muscle contraction. However, the widespread application of these methods may be limited by their risks as well as the technical and environmental requirements of placement and care. Non-invasive stimulation would offer a valuable alternative method to maintain diaphragm health while overcoming these limitations.
METHODS
We applied non-invasive electrical stimulation to the phrenic nerve in the neck in healthy volunteers. Respiratory pressure and flow, diaphragm electromyography and mechanomyography, and ultrasound visualization were used to assess the diaphragmatic response to stimulation. The electrode positions and stimulation parameters were systematically varied in order to investigate the influence of these parameters on the ability to induce diaphragm contraction with non-invasive stimulation.
RESULTS
We demonstrate that non-invasive capture of the phrenic nerve is feasible using surface electrodes without the application of pressure, and characterize the stimulation parameters required to achieve therapeutic diaphragm contractions in healthy volunteers. We show that an optimal electrode position for phrenic nerve capture can be identified and that this position does not vary as head orientation is changed. The stimulation parameters required to produce a diaphragm response at this site are characterized and we show that burst stimulation above the activation threshold reliably produces diaphragm contractions sufficient to drive an inspired volume of over 600 ml, indicating the ability to produce significant diaphragmatic work using non-invasive stimulation.
CONCLUSION
This opens the possibility of non-invasive systems, requiring minimal specialist skills to set up, for maintaining diaphragm function in the intensive care setting.
Topics: Critical Care; Diaphragm; Electric Stimulation; Humans; Phrenic Nerve; Respiration, Artificial; Ventilators, Mechanical
PubMed: 35377472
DOI: 10.1111/aor.14244 -
Anesthesiology and Pain Medicine Aug 2021This review examines the use of novel US-guided nerve blocks in clinical practice. Erector spinae block is a regional anesthesia technique doing by injecting a local... (Review)
Review
This review examines the use of novel US-guided nerve blocks in clinical practice. Erector spinae block is a regional anesthesia technique doing by injecting a local anesthetic among the erector spinae muscle group and transverse processes. The phrenic nerve is a branch of the cervical plexus, arising from the anterior rami of cervical nerves C3, C4, and C5. The quadratus lumborum muscle is located along the posterior abdominal wall. It originates from the transverse process of the L5 vertebral body, the iliolumbar ligament, and the iliac crest. US-guided peripheral nerve procedures have a considerable scope of use, including treating headaches and hiccups to abdominal surgical pain, cesarean sections, musculoskeletal pathologies. These nerve blocks have been an effective addition to clinical anesthesia practice. The use of peripheral nerve blocks has improved postoperative pain, lessened the use of opioids and their potential side effects, and decreased the incidence of sleep disturbance in patients. More research should be done to further delineate the potential benefits of these blocks.
PubMed: 34692446
DOI: 10.5812/aapm.118278 -
Medicina (Kaunas, Lithuania) Jan 2023: Ipsilateral shoulder pain (ISP) is a common complication after thoracic surgery. Severe ISP can cause ineffective breathing and impair shoulder mobilization. Both... (Meta-Analysis)
Meta-Analysis Review
Efficacy of Phrenic Nerve Block and Suprascapular Nerve Block in Amelioration of Ipsilateral Shoulder Pain after Thoracic Surgery: A Systematic Review and Network Meta-Analysis.
: Ipsilateral shoulder pain (ISP) is a common complication after thoracic surgery. Severe ISP can cause ineffective breathing and impair shoulder mobilization. Both phrenic nerve block (PNB) and suprascapular nerve block (SNB) are anesthetic interventions; however, it remains unclear which intervention is most effective. The purpose of this study was to compare the efficacy and safety of PNB and SNB for the prevention and reduction of the severity of ISP following thoracotomy or video-assisted thoracoscopic surgery. Studies published in PubMed, Embase, Scopus, Web of Science, Ovid Medline, Google Scholar and the Cochrane Library without language restriction were reviewed from the publication's inception through 30 September 2022. Randomized controlled trials evaluating the comparative efficacy of PNB and SNB on ISP management were selected. A network meta-analysis was applied to estimate pooled risk ratios (RRs) and weighted mean difference (WMD) with 95% confidence intervals (CIs). : Of 381 records screened, eight studies were eligible. PNB was shown to significantly lower the risk of ISP during the 24 h period after surgery compared to placebo (RR 0.44, 95% CI 0.34 to 0.58) and SNB (RR 0.43, 95% CI 0.29 to 0.64). PNB significantly reduced the severity of ISP during the 24 h period after thoracic surgery (WMD -1.75, 95% CI -3.47 to -0.04), but these effects of PNB were not statistically significantly different from SNB. When compared to placebo, SNB did not significantly reduce the incidence or severity of ISP during the 24 h period after surgery. This study suggests that PNB ranks first for prevention and reduction of ISP severity during the first 24 h after thoracic surgery. SNB was considered the worst intervention for ISP management. No evidence indicated that PNB was associated with a significant impairment of postoperative ventilatory status.
Topics: Humans; Phrenic Nerve; Shoulder Pain; Nerve Block; Thoracic Surgery; Pain, Postoperative; Network Meta-Analysis; Injections, Intra-Articular
PubMed: 36837476
DOI: 10.3390/medicina59020275 -
Journal of Clinical Medicine Jan 2021Central sleep apnea (CSA) is a common comorbidity in patients with heart failure (HF) and has been linked to increased morbidity and mortality risk. In addition, CSA is...
BACKGROUND
Central sleep apnea (CSA) is a common comorbidity in patients with heart failure (HF) and has been linked to increased morbidity and mortality risk. In addition, CSA is associated with impaired quality of life, reduced physical performance capacity, and hypoxemia. Phrenic nerve stimulation (PNS) is a novel approach to the treatment of CSA and has been shown to be safe and effective in this indication. However, there are currently no data on the effects of PNS on physical performance and hypoxia in CSA HF patients, both of which have been shown to be linked to mortality in HF.
METHODS
This prospective study enrolled patients with HF and CSA diagnosed using polysomnography. All were implanted with a PNS system (remedē system, Respicardia Inc., Minnetonka, MN, USA) for the treatment of CSA. Examinations included polysomnography (to determine hypoxemic burden), echocardiography and a standardized 6-min walk test prior to device implantation (baseline) and after 6 months of follow-up.
RESULTS
A total of 24 patients were enrolled (mean age 67.1 ± 11.2 years, 88% male). The 6-min walk distance was 369.5 ± 163.5 m at baseline and significantly improved during follow-up (to 410 ± 169.7 m; = 0.035). Hypoxemic burden, determined based on time with oxygen saturation < 90% improved from 81 ± 55.8 min at baseline to 27.9 ± 42.8 min during PNS therapy ( < 0.01).
CONCLUSION
In addition to safely and effectively treating CSA, PNS is also associated with improved physical performance capacity and reduced hypoxemic burden in patients with HF.
PubMed: 33429858
DOI: 10.3390/jcm10020202 -
JACC. Heart Failure Apr 2020The substantial burden of heart failure has inspired innovation in medical device development for decades, and this development continues to be a touchstone in the... (Review)
Review
The substantial burden of heart failure has inspired innovation in medical device development for decades, and this development continues to be a touchstone in the success story of combined medical and device therapy. Recently, baroreflex activation therapy, interatrial shunts, and phrenic nerve stimulation have shown promise in treating patients with heart failure. We seek to provide background about the design, function, and early clinical experience with these 3 novel heart failure devices. In addition, an understanding of the individual regulatory journey of these devices, some of which is ongoing, is informative for future device development and clinical use.
Topics: Baroreflex; Cardiac Surgical Procedures; Electric Stimulation Therapy; Equipment Design; Heart Atria; Heart Failure; Humans; Implantable Neurostimulators; Phrenic Nerve; Stroke Volume; Ventricular Function, Left
PubMed: 32241533
DOI: 10.1016/j.jchf.2019.11.006 -
Seminars in Pediatric Surgery Feb 2024Diaphragm pacing is a ventilation strategy in respiratory failure. Most of the literature on pacing involves adults with common indications being spinal cord injury and... (Review)
Review
Diaphragm pacing is a ventilation strategy in respiratory failure. Most of the literature on pacing involves adults with common indications being spinal cord injury and amyotrophic lateral sclerosis (ALS). Previous reports in pediatric patients consist of case reports or small series; most describe direct phrenic nerve stimulation for central hypoventilation syndrome. This differs from adult reports that focus most commonly on spinal cord injuries and the rehabilitative nature of diaphragm pacing. This review describes the current state of diaphragm pacing in pediatric patients. Indications, current available technologies, surgical techniques, advantages, and pitfalls/problems are discussed.
Topics: Child; Humans; Amyotrophic Lateral Sclerosis; Diaphragm; Phrenic Nerve; Respiratory Insufficiency
PubMed: 38245992
DOI: 10.1016/j.sempedsurg.2024.151386