Orthopnea secondary to brachial plexitis with bilateral diaphragmatic paralysis.

BACKGROUND: Diaphragmatic paralysis can present with orthopnea. We report a unique presentation of bilateral diaphragmatic paralysis, an uncommon diagnosis secondary to an unusual cause, brachial plexitis. This report thoroughly describes the patient's presentation, workup, management, and outcome. It also reviews the literature on diaphragmatic paralysis and Parsonage-Turner syndrome. CASE PRESENTATION: A 50-year-old male patient developed insidious orthopnea associated with left shoulder and neck pain over three months with no associated symptoms. On examination, marked dyspnea was observed when the patient was asked to lie down; breath sounds were present and symmetrical, and the neurological examination was normal. The chest radiograph showed an elevated right hemidiaphragm. Echocardiogram was normal. There was a 63% positional reduction in Forced Vital Capacity and maximal inspiratory and expiratory pressures on pulmonary function testing. The electromyogram was consistent with neuromuscular weakness involving both brachial plexus and diaphragmatic muscle (Parsonage and Turner syndrome). CONCLUSIONS: Compared to unilateral, bilateral diaphragmatic paralysis may be more challenging to diagnose. On PFT, reduced maximal respiratory pressures, especially the maximal inspiratory pressure, are suggestive. Parsonage-Turner syndrome is rare, usually with unilateral diaphragmatic paralysis, but bilateral cases have been reported.

Weaning failure due to isolated residual diaphragmatic paralysis after cervical spinal cord ischemia following aortic surgery- a case report.

BACKGROUND: Bilateral diaphragmatic dysfunction can lead to dyspnea and recurrent respiratory failure. In rare cases, it may result from high cervical spinal cord ischemia (SCI) due to anterior spinal artery syndrome (ASAS). We present a case of a patient experiencing persistent isolated diaphragmatic paralysis after SCI at level C3/C4 following thoracic endovascular aortic repair (TEVAR) for Kommerell's diverticulum. This is, to our knowledge, the first documented instance of a patient fully recovering from tetraplegia due to SCI while still exhibiting ongoing bilateral diaphragmatic paralysis. CASE PRESENTATION: The patient, a 67-year-old male, presented to the Vascular Surgery Department for surgical treatment of symptomatic Kommerell's diverticulum in an aberrant right subclavian artery. After successful surgery in two stages, the patient presented with respiratory insufficiency and flaccid tetraparesis consistent with anterior spinal artery syndrome with maintained sensibility of all extremities. A computerized tomography scan (CT) revealed a high-grade origin stenosis of the left vertebral artery, which was treated by angioplasty and balloon-expandable stenting. Consecutively, the tetraparesis immediately resolved, but weaning remained unsuccessful requiring tracheostomy. Abdominal ultrasound revealed a residual bilateral diaphragmatic paralysis. A repeated magnetic resonance imaging (MRI) 14 days after vertebral artery angioplasty confirmed SCI at level C3/C4. The patient was transferred to a pulmonary clinic with weaning center for further recovery. CONCLUSIONS: This novel case highlights the need to consider diaphragmatic paralysis due to SCI as a cause of respiratory failure in patients following aortic surgery. Diaphragmatic paralysis may remain as an isolated residual in these patients.

Diaphragm-sparing efficacy of subparaneural upper trunk block for arthroscopic shoulder surgery: A randomised controlled trial.

BACKGROUND: Inter-scalene block (ISB) is associated with an inevitable risk of hemi-diaphragmatic paresis (HDP). To reduce the risk of HDP, an upper trunk block (UTB) has been proposed at the brachial plexus division level. OBJECTIVE: We hypothesised that UTB would be associated with a lower incidence of HDP than ISB while providing sufficient analgesia following arthroscopic shoulder surgery. DESIGN: Randomised controlled trial. SETTING: A tertiary teaching hospital. PATIENTS: Seventy patients aged 20 to 80 years undergoing arthroscopic rotator cuff repair. INTERVENTION: Ultrasound-guided ISB or UTB was performed with 5 ml 0.75% ropivacaine. MAIN OUTCOME MEASURES: The primary outcome was the incidence of complete HDP, assessed by diaphragm excursion using ultrasound, defined as a decrease to 25% or less of baseline or occurrence of paradoxical movement. Postoperative pulmonary function change, pain scores, opioid consumption and pain-related outcomes were the secondary outcomes. RESULTS: The UTB group had a significantly lower incidence of complete HDP than the ISB group [5.9% (2/34) vs. 41.7% (15/36); absolute difference, 35.8%; 95% confidence interval (CI), 17.8 to 53.7%; P  < 0.001]. The postblockade decline in pulmonary function was more pronounced in the ISB group than that in the UTB group. The pain score at 1 h postoperatively was not significantly different between the groups (ISB vs. UTB group: median 0 vs. 1; median difference, -1; 95% CI, -2 to 0.5). No significant difference was observed in any other secondary outcomes. CONCLUSION: UTB was associated with a lower incidence of HDP compared with ISB while providing excellent analgesia in arthroscopic shoulder surgery. TRIAL REGISTRATION: Clinical Trial Registry of Korea ( https://cris.nih.go.kr ) identifier: KCT0007002. IRB NUMBER: Chungnam National University Hospital Institutional Review Board No. 2021-12-069.

Hepatitis E and diaphragmatic dysfunction: Case series and review of the literature.

INTRODUCTION: The causes of diaphragmatic paresis are manifold. An association between neuralgic amyotrophy (NA) and hepatitis E virus (HEV) infection has been reported. We wondered about the prevalence of diaphragmatic disfunction and hepatitis E infection in our clinic. METHODS: From July 1st, 2020 to August 31st, 2023, patients presenting with diaphragmatic dysfunction and simultaneous clinical symptoms of an acute NA, or a history of NA, as well as patients with previously unexplained diaphragmatic dysfunction were examined for HEV infection. RESULTS: By August 31st, 2023, 13 patients with diaphragmatic dysfunction and HEV infection were diagnosed (4 women, 9 men). Mean age was 59 ± 10 years. Liver values were normal in all patients. The median latency to diagnosis was five months (range: 1-48 months); nine patients, 4 of them with typical symptoms of NA, presented with acute onset three patients showed bilateral diaphragmatic dysfunction. All patients had a positive IgG immunoblot. Seven patients, three with NA, had an elevated hepatitis E IgM titer and six of them also a positive IgM immunoblot. In all cases, O2C hepatitis genotype 3 was identified. In eight cases, all those with a high IgG titer >125, the O2 genotype 1 was also detected. CONCLUSION: NA that shows involvement of the phrenic nerve resulting in diaphragmatic dysfunction and dyspnoea, may be associated with HEV infection. The observation of 13 patients with diaphragmatic dysfunctions and HEV infection within a period of three years indicates a high number of undetected HEV-associated diaphragmatic dysfunction in the population, especially in the absence of NA symptoms. Therefore, even in diaphragmatic dysfunction without NA symptoms and causative damaging event, HEV infection should be considered, as it may represent a subform of NA with only phrenic nerve involvement. Therapy of HEV-associated diaphragmatic dysfunction in the acute phase is an open question. In view of the poor prognosis for recovery, antiviral therapy should be discussed. However, no relevant data are currently available.

Shrinking lung syndrome mimicking diaphragmatic palsy in systemic lupus erythematosus.

A 25-year-old woman presented with 1 year of progressive orthopnoea, initially explained as bilateral diaphragmatic paresis caused by seronegative myasthenia gravis. She required assisted ventilation and received pyridostigmine and corticosteroids. She had minimal (particularly proximal) symmetrical tetraparesis with apparent bilateral diaphragmatic weakness, but had normal sensation. Further investigation suggested an overlap myositis with shrinking lung syndrome from systemic lupus erythematosus. She improved following immunosuppression with pulse corticosteroids and rituximab, and at 3 months no longer needed bilevel positive airway pressure support.

[Quality of life in patients with postoperative unilateral diaphragm relaxation]. / Kachestvo zhizni patsientov s odnostoronnei relaksatsiei diafragmy posle khirurgicheskogo lecheniya.

OBJECTIVE: To evaluate the quality of life before and after video-assisted thoracoscopic plication of relaxed dome of diaphragm. MATERIAL AND METHODS: The study included 17 patients operated on for unilateral relaxation of diaphragm. We analyzed quality of life in preoperative period, 1, 3, 6 and 12 months after surgery using the SF-36 and EuroQ-5D-5L questionnaires. To assess the impact of abnormality on respiratory function, we estimated diaphragm position, spirometry data and SGRQ scores. RESULTS: FVC increased by 16.5% after 1 month, 19.5% after 6 months and 20.1% after 12 months. In addition, FEV1 significantly increased (by 12.6% after 1 month, 10.1% after 6 months and 12.7% after 12 months). Mean values of diaphragm elevation in postoperative period decreased by 25.5-25.6%. According to the SF-36 and EuroQ-5D-5L questionnaires, physical and psychological health components significantly increased within a month after surgical treatment. According to the SGRQ questionnaire, influence of disease on overall status decreased a month after surgery as evidences by lower total score (p<0.05). CONCLUSION: Objective and survey data revealed significant improvement in quality of life after surgery. A trend towards higher quality of life was demonstrated by all questionnaires in a month after surgery.

Proof of concept of an accelerometer as a trigger for unilateral diaphragmatic pacing: a porcine model.

BACKGROUND: Unilateral diaphragmatic paralysis in patients with univentricular heart is a known complication after pediatric cardiac surgery. Because diaphragmatic excursion has a significant influence on perfusion of the pulmonary arteries and hemodynamics in these patients, unilateral loss of function leads to multiple complications. The current treatment of choice, diaphragmatic plication, does not lead to a full return of function. A unilateral diaphragmatic pacemaker has shown potential as a new treatment option. In this study, we investigated an accelerometer as a trigger for a unilateral diaphragm pacemaker (closed-loop system). METHODS: Seven pigs (mean weight 20.7 ± 2.25 kg) each were implanted with a customized accelerometer on the right diaphragmatic dome. Accelerometer recordings (mV) of the diaphragmatic excursion of the right diaphragm were compared with findings using established methods (fluoroscopy [mm]; ultrasound, M-mode [cm]). For detection of the amplitude of diaphragmatic excursions, the diaphragm was stimulated with increasing amperage by a cuff electrode implanted around the right phrenic nerve. RESULTS: Results with the different techniques for measuring diaphragmatic excursions showed correlations between accelerometer and fluoroscopy values (correlation coefficient 0.800, P < 0.001), accelerometer and ultrasound values (0.883, P < 0.001), and fluoroscopy and ultrasound values (0.816, P < 0.001). CONCLUSION: The accelerometer is a valid method for detecting diaphragmatic excursion and can be used as a trigger for a unilateral diaphragmatic pacemaker.

Comparison of pulmonary function during interscalene block vs. supraclavicular block: a single-center, double-blind, randomized trial.

BACKROUND: The supraclavicular plexus block (SCB) and interscalene plexus block (ISB) have the potential to pulmonary function, the duration of the potential remains uncertain. So, we compared the effect of SCB and ISB on pulmonary function, especially the duration time. METHODS: Ninety-six patients were finally allocated to group I and group S. The ISB and the SCB procedures were performed with ultrasound guidance before anesthesia induction. An investigator recorded the diaphragm mobility and respiratory function test indicators before the block (T0) and at 30 min (T30 min), 4 h (T4), 8 h (T8), and 12 h (T12) after the block. The diaphragmatic paralysis rate was calculated for above timepoint. The VAS, the recovery time for the sensory and motor block, and adverse reactions within 24 h of administering the block were also recorded. RESULTS: The recovery times of diaphragm mobility in group I were longer than those in group S. Compared with group I, group S had a significantly lower diaphragmatic paralysis rate during eupnea breathing at T30 min and T8 after the block. Similarly, group S had a significantly lower diaphragmatic paralysis rate at deep breathing at T30 min, T8, and T12 after the block. The recovery times of FEV1 and FVC in group I were longer than those in group S. The other results were not statistically significant. CONCLUSIONS: Ultrasound-guided ISB resulted in a longer periods with a suppressive effect on pulmonary function than SCB. TRIALS REGISTRATION: 17/12/2019, ChiCTR1900028286.

Plication for diaphragm paralysis after paediatric cardiac surgery: a single-centre experience.

OBJECTIVE: Diaphragm paralysis is a well-known complication following surgery for CHDs, which increases morbidity, mortality, and length of hospital stay as well as costs. Herein, we present our experience with diaphragm plication following paralysis of the phrenic nerve encountered after paediatric cardiac surgery. METHODS: This study retrospectively reviewed the medical records of 23 diaphragm plications in 20 patients who underwent paediatric cardiac surgery between January 2012 and January 2022. The patients were carefully selected based on aetiology and a combination of clinical manifestation and chest imaging characteristics including chest X-ray, ultrasonography, and fluoroscopy. RESULTS: Twenty-three successful plications were performed in 20 patients (15 males and 5 females) out of a total of 1938 operations performed in our centre. Mean age and body weight were 18.2 ± 17.1 months and 8.3 ± 3.7 kg, respectively. The period between the cardiac surgery and diaphragmatic plication was 18.7 ± 15.1 days. The highest incidence of diaphragm paralysis was encountered in systemic to pulmonary artery shunt patients with 7 out of 152 patients (4.6%). Any mortality was not encountered during a mean follow-up period of 4.3 ± 2.6 years. CONCLUSIONS: Early results of plication of the diaphragm following phrenic nerve palsy in symptomatic patients who underwent paediatric cardiac surgery are encouraging. Evaluation of the diaphragmatic function should be a routine part of post-operative echocardiography. Diaphragm paralysis may be a consequence of dissection, contusion, stretching, and thermal injury both in terms of hypothermia and hyperthermia.

[Robotic Diaphragm Plication]. / Roboterassistierte thorakoskopische Zwerchfellraffung.

Acquired unilateral hemidiaphragm elevation is characterised by dyspnoea, which is typically aggravated when lying down, bending over or during swimming. The most common causes are idiopathic or due to injury to the phrenic nerve during cervical or cardio-thoracic surgery. To date, surgical diaphragm plication remains the only effective treatment. The aim of the procedure is to plicate the diaphragm to restore its tension and thus improve breathing mechanics, increase the available space for the lung and reduce compression from abdominal organs. In the past, various techniques using open and minimally invasive approaches have been described. Robot-assisted thoracoscopic diaphragm plication combines the advantages of a minimally invasive approach with excellent visualisation and freedom of movement. It was shown to be a safe technique which is easy to establish and can significantly improve pulmonary function.

An Analysis of Respiratory Muscle Paralysis of Adult Patients in Guillain-Barré Syndrome: A Retrospective Analysis.

Respiratory muscle paralysis is known as a very common complication of Guillain-Barré syndrome (GBS). However, most research has focused on its later stages rather than its earlier stages, including the prognosis of patients with this condition, or factors that act as early predictors of risk. Therefore, our study aimed to identify early predictors of respiratory muscle paralysis in patients with GBS and determine the short-term prognosis of such patients. We recruited 455 GBS patients (age ≥ 18) who had been hospitalized in the First Affiliated Hospital of Harbin Medical University between 2016 and 2021, retrospectively. We recorded clinical and laboratory data and used linear and logistic regression analysis to investigate the relationship between early clinical, examination results, and subsequent respiratory muscle paralysis. Among the 455 patients, 129 were assigned to a respiratory muscle paralysis group and 326 were assigned to a non-respiratory muscle paralysis group. Compared with the non-affected group, the time from onset to admission was shorter (p = 0.0003), and the Medical Research Council (MRC) score at admission and discharge was smaller in the affected group (p < 0.0001). Compared with the non-affected group, the affected group had higher Hughes and Erasmus GBS Respiratory Insufficiency Score (EGRIS) scores at admission and longer hospital stays (p < 0.0001). Patients in the affected group were more likely to have bulbar palsy and lung infections (p < 0.0001). To conclude, bulbar palsy, a higher EGRIS score and Hughes score at admission, a lower MRC score, and a shorter time between onset and admission, are all predictive risk factors for respiratory muscle paralysis in patients with GBS. An increase in any of these factors increases the risk of muscle paralysis. Patients with respiratory muscle paralysis have a poorer short-term prognosis than those without respiratory muscle paralysis. Therefore, we should attempt to identify patients with one or more of these characteristics in the early stages of admission, provide ventilation management, and administer IMV treatment if necessary.

The many paths to diagnose diaphragmatic paralysis: Cardiopulmonary ultrasound on stage.

Abnormal diaphragmatic motion (ADM) due to phrenic nerve injury is a recognized complication of cardiac surgery and several diagnostic techniques can be used to determine the diagnosis. Due to its relationship with the diaphragm, cardiac kinetics is affected by the abnormal movement of the diaphragm in cases of left hemidiaphragm paralysis. The authors present a case of diaphragmatic paralysis in which the initial diagnosis is made through echocardiography.

Persistent unilateral diaphragmatic paralysis in the course of Coronavirus Disease 2019 pneumonia: a case report.

Coronavirus Disease 2019 infections can cause a wide range of symptoms, particularly in the respiratory system. Diaphragmatic paralysis is a rare condition that is poorly documented in the literature. We present the case of a 38-year-old Caucasian male adult who developed unilateral diaphragmatic paralysis during the course of the disease. The patient presented to the Emergency Department with fever, cough, and dyspnea, was admitted, and was immediately fitted with a high flow nasal cannula. When his condition worsened eight days later, he was admitted to the Intensive Care Unit and a tracheostomy was performed. A CT scan of the chest revealed significant left diaphragm elevation. On the 48th day, the patient gradually improved and was discharged. The paralysis of the diaphragm persisted three months later in the follow-up examination. This case illustrates a possible neuromuscular virus invasion that may have an impact on the patient's health after discharge.

[The impact of unilateral diaphragmatic paralysis on sleep-disordered breathing: a scoping review]. / L'impact de la paralysie diaphragmatique unilatérale sur les troubles respiratoires du sommeil : une revue exploratoire.

BACKGROUND: Unilateral diaphragm paralysis (UDP) may potentially worsen sleep-disordered breathing (SDB). Unilateral diaphragm paralysis has been associated with proximal brachial plexus blockade, such as interscalene and supraclavicular block. The impact of UDP in patients with SDB is not known in this context. The objectives of this scoping review were to explore the associations between UDP and worsening SDB severity, oxygenation, and pulmonary function. METHODS: A systematic search was developed, peer-reviewed, and applied to Embase, Medline, CINAHL, and Cochrane databases to include studies involving adult patients (≥ 18 yr) with SDB, where the effects of UDP on SDB severity, oxygenation, and pulmonary function were examined. RESULTS: Six studies (n = 100 patients) with UDP and SDB were included. The sample population was derived exclusively from respirology-sleep clinics, and none were surgical patients. Compared with control (no UDP), UDP was associated with an increased respiratory disturbance index, most pronounced during rapid eye movement (REM) sleep and supine sleep. Supine and REM sleep were associated with obstructive and mixed (both obstructive and central) events, respectively. Compared with control, UDP was associated with a lower mean and minimum oxygen saturation and arterial oxygen tension during all sleep stages and in all body positions. The majority of UDP patients were found to have clinically significant reductions in mean forced expiratory volume in one second and forced vital capacity values, consistent with restrictive ventilatory pattern. CONCLUSION: We observed an association between UDP and increasing SDB severity, particularly during REM sleep and while sleeping in the supine position. Although we identified weaknesses in study design and lack of perioperative data, anesthesiologists should be aware of this association when considering proximal brachial plexus blockade in patients with SDB.

RéSUMé: CONTEXTE: La paralysie diaphragmatique unilatérale (PDU) peut potentiellement aggraver les troubles respiratoires du sommeil (TRS). La PDU est associée aux blocs du plexus brachial proximal, tel que les blocs interscalénique et supraclaviculaire. L'impact de la PDU chez les patients atteints de TRS n'est pas connu dans ce contexte. Les objectifs de cette revue exploratoire étaient d'explorer les associations entre la PDU et l'aggravation de la sévérité des TRS, l'oxygénation, et la fonction pulmonaire. MéTHODE: Une recherche systématique a été mise au point, évaluée par des pairs et appliquée aux bases de données Embase, Medline, CINAHL et Cochrane afin d'inclure les études portant sur des patients adultes (≥ 18 ans) atteints de TRS, où les effets d'une PDU sur la sévérité des TRS, sur l'oxygénation et la fonction pulmonaire étaient examinés. RéSULTATS: Six études (n = 100 patients) portant sur la PDU et les TRS ont été incluses. La population étudiée provenait exclusivement de cliniques de respirologie-sommeil, et ne comptait aucun patient chirurgical. Comparativement au groupe témoin (aucune PDU), la PDU a été associée à un index accru de troubles respiratoires, lesquels étaient les plus prononcés pendant le sommeil paradoxal et en position de décubitus dorsal. Le sommeil en décubitus dorsal et le sommeil paradoxal ont été associés à des événements obstructifs et mixtes (obstructifs et centraux), respectivement. Comparativement au groupe témoin, la PDU a été associée à une saturation en oxygène et à une tension artérielle d'oxygène moyennes et minimales inférieures pendant tous les stades de sommeil et dans toutes les positions. Chez la majorité des patients atteints de PDU, des réductions cliniquement significatives des valeurs du volume expiratoire forcé moyen en une seconde et de la capacité vitale forcée ont été observées, des données compatibles avec une physiologie respiratoire restrictive. CONCLUSION: Nous avons observé une association entre la paralysie diaphragmatique unilatérale et une sévérité augmentée des troubles respiratoires du sommeil, particulièrement pendant le sommeil paradoxal et en décubitus dorsal. Malgré l'identification de faiblesses dans la conception des études et d'un manque de données périopératoires, les anesthésiologistes devraient garder à l'esprit cette association lorsqu'ils envisagent un bloc du plexus brachial proximal chez les patients souffrant de TRS.

Fluorographic findings of diaphragmatic paralysis with spontaneous recovery.

BACKGROUND: Postoperative diaphragmatic paralysis is an unavoidable complication of cardiovascular surgery. Although diaphragmatic plication, as a surgical treatment, can be performed, spontaneous recovery is possible. We aimed to identify differences in fluorographic findings of diaphragmatic paralysis between pediatric patients with and without spontaneous recovery within 1 year of intrathoracic surgery. METHODS: Ten children, who had been followed-up for at least 1 year post-surgery and who had not received diaphragmatic plication were included and classified into those with or without spontaneous recovery. The presence or absence of the paradoxical movement of the diaphragm and mediastinum was evaluated based on fluorographic findings. Fisher's exact test was used to compare the presence or absence of paradoxical movement between the groups. RESULTS: Eight patients experienced spontaneous recovery. The mean ± standard deviation time to spontaneous recovery was 150 ± 114 days (range, 18-338 days). In the spontaneous recovery group, no patient had paradoxical movement of the mediastinum, and a significant between-group difference was observed in the presence of the paradoxical movement of the mediastinum (present/absent in patients with vs. without spontaneous recovery: 0/8 vs. 2/0, P = 0.02). There was no significant between-group difference in paradoxical movement of the diaphragm (present/absent in patients with vs. without spontaneous recovery: 1/7 vs. 2/0, P = 0.07). Pediatric patients without paradoxical movement of the mediastinum spontaneously recovered within 1 year of intrathoracic surgery. CONCLUSIONS: Pediatric patients without paradoxical movement of the mediastinum, based on fluorography findings, spontaneously recovered within 1 year of surgery. The timing of spontaneous recovery varied between cases.

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.

[DIAPHRAGMATIC PARALYSIS].

INTRODUCTION: One-sided diaphragmatic paralysis is a common phenomenon which is usually a-symptomatic. In case of acute onset or if there is an underlying lung disease, the phenomenon may be symptomatic and even limiting. In this article, we present a patient who arrived with subacute shortness of breath when lying down. She underwent thorough investigations but, as happens in most cases, the cause of the paralysis was not identified and it remains idiopathic. The authors present an overview of the etiology, differential diagnosis and treatment of diaphragmatic paralysis.

Initial Assessment of the Percutaneous Electrical Phrenic Nerve Stimulation System in Patients on Mechanical Ventilation.

OBJECTIVES: Maintaining diaphragm work using electrical stimulation during mechanical ventilation has been proposed to attenuate ventilator-induced diaphragm dysfunction. This study assessed the safety and feasibility of temporary percutaneous electrical phrenic nerve stimulation on user-specified inspiratory breaths while on mechanical ventilation. DESIGN: Two-center, nonblinded, nonrandomized study. SETTING: Hospital ICU. PATIENTS: Twelve patients mechanically ventilated from 48 hours to an expected 7 days. INTERVENTIONS: Leads were inserted to lie close to the phrenic nerve in the neck region using ultrasound guidance. Two initial patients had left-sided placement only with remaining patients undergoing bilateral lead placement. Percutaneous electrical phrenic nerve stimulation was used for six 2-hour sessions at 8-hour intervals over 48 hours. MEASUREMENTS AND MAIN RESULTS: Data collected included lead deployment success, nerve conduction, ventilation variables, work of breathing, electrical stimulation variables, stimulation breath synchrony, and diaphragm thickness measured by ultrasound at baseline, 24, and 48 hours. Primary endpoints included ability to capture the left and/or right phrenic nerves and maintenance of work of breathing within defined limits for 80% of stimulated breaths. Lead insertion was successful in 21 of 22 attempts (95.5%). Analysis of 36,059 stimulated breaths from 10 patients with attempted bilateral lead placement demonstrated a mean inspiratory lag for phrenic nerve stimulation of 23.7 ms (p < 0.001 vs null hypothesis of <88ms). Work of breathing was maintained between 0.2 and 2.0 joules/L 96.8% of the time, exceeding the 80% target. Mean diaphragm thickness increased from baseline by 7.8% at 24 hours (p = 0.022) and 15.0% at 48 hours (p = 0.0001) for patients receiving bilateral stimulation after excluding one patient with pleural effusion. No serious device/procedure-related adverse events were reported. CONCLUSIONS: The present study demonstrated the ability to safely and successfully place percutaneous electrical phrenic nerve stimulation leads in patients on mechanical ventilation and the feasibility of using this approach to synchronize electrical stimulation with inspiration while maintaining work of breathing within defined limits.

A nomogram to predict mechanical ventilation in Guillain-Barré syndrome patients.

INTRODUCTION: Guillain-Barré syndrome (GBS) is one of the most common causes of acute flaccid paralysis, with up to 20%-30% of patients requiring mechanical ventilation. The aim of our study was to develop and validate a mechanical ventilation risk nomogram in a Chinese population of patients with GBS. METHODS: A total of 312 GBS patients were recruited from January 1, 2015, to June 31, 2018, of whom 17% received mechanical ventilation. The least absolute shrinkage and selection operator (LASSO) regression model was used to select clinicodemographic characteristics and blood markers that were then incorporated, using multivariate logistic regression, into a risk model to predict the need for mechanical ventilation. The model was characterized and assessed using the C-index, calibration plot, and decision curve analysis. The model was validated using bootstrap resampling in a prospective study of 114 patients recruited from July 1, 2018, to July 10, 2019. RESULTS: The predictive model included hospital stay, glossopharyngeal and vagal nerve deficits, Hughes functional grading scale scores at admission, and neutrophil/lymphocyte ratio (NLR). The model showed good discrimination with a C-index value of 0.938 and good calibration. A high C-index value of 0.856 was reached in the validation group. Decision curve analysis demonstrated the clinical utility of the mechanical ventilation nomogram. CONCLUSIONS: A nomogram incorporating hospital stay, glossopharyngeal and vagal nerve deficits, Hughes functional grading scale scores at admission, and NLR may reliably predict the probability of requiring mechanical ventilation in GBS patients.