Neuromuscular disease and the pulmonologist.

PURPOSE OF REVIEW: The heterogeneous nature of neuromuscular disorders (NMDs) continues to promote slow but steady advances in diagnosis, classification, and treatment. This review focuses on the updates in the general management and treatment of NMDs, with emphasis on key updates in muscular dystrophy, myotonic dystrophy, mitochondrial myopathy, spinal muscular atrophy, and hereditary neuropathies. RECENT FINDINGS: Current research shows that improvements in morbidity and mortality in various NMDs may be possible. Key components include advances in identification and classification of individual NMDs; attention to anesthetic and surgical risks; aggressive pulmonary care; and implementations of a proactive, multidisciplinary, standard-of-care approach. Innovative molecular and pharmaceutical therapeutic options are being investigated in many of these disorders, but unfortunately no new intervention has borne out. SUMMARY: Important advances were made in the last year in the field of neuromuscular disease. However, because of their heterogeneous nature and rarity, diagnosis and treatment of these disorders either as a single disorder or as a group continue to be both a clinical and a research challenge. It is of utmost importance that clinicians and researchers be aware of these disorders to aid in identification and treatment.

Laparoscopic Nissen fundoplication during gastrostomy tube placement and noninvasive ventilation may improve survival in type I and severe type II spinal muscular atrophy.

Progressive respiratory muscle weakness with bulbar involvement is the main cause of morbidity and mortality in type I and severe type II spinal muscular atrophy. Noninvasive positive pressure ventilation techniques coupled with laparoscopic gastrointestinal procedures may allow for improved morbidity and mortality. The authors present a series of 7 spinal muscular atrophy patients (6 type I and 1 severe type II) who successfully underwent laparoscopic gastrostomy tube insertion coupled with Nissen fundoplication and early postoperative extubation using noninvasive positive pressure ventilation techniques. The authors measured the length of survival and the frequencies of pneumonia and hospitalization before and after surgery as outcomes of these new surgical and medical interventions. All 7 patients had respiratory symptoms (unmanageable oropharyngeal secretions, cough, pneumonia), difficulty feeding, and weight loss. Six patients had documented reflux via diagnostic testing preoperatively. Five patients were on noninvasive positive pressure ventilation and other supportive respiratory therapies prior to surgery. All 7 patients survived the procedures. By August 2006, 5 patients with type I and 1 with severe type II spinal muscular atrophy were alive and medically stable at home 1.5 months to 41 months post-op. One patient with type I expired approximately 5 months post-op due to obstructive apnea. This case series demonstrates that laparoscopic gastrostomy tube placement coupled with Nissen fundoplication and noninvasive positive pressure ventilation can be successfully used as a treatment option to allow for early postoperative extubation and to optimize quality of life in type I and severe type II spinal muscular atrophy patients.

Preoperative predictors of prolonged postoperative mechanical ventilation in children following scoliosis repair.

Scoliosis is associated with progressive restrictive lung disease and an increased risk of pulmonary complications following surgical correction. Identification of higher risks for prolonged postoperative mechanical ventilation (MV) improves postoperative care. Our objective was to determine if preoperative pulmonary function tests (PFT) predict prolonged postoperative MV (defined as MV >or=3 days). We correlated preoperative PFT (forced expired volume in 1 sec, FEV1; vital capacity, VC; inspiratory capacity, IC; maximal inspiratory pressure, MIP; total lung capacity, TLC; and residual volume, RV) and postoperative MV days in 125 patients who had scoliosis surgery (aged 13.7 +/- 3.0 (SD) years) from January 1990-July 2001. We had 71 male and 54 female patients. Scoliosis types were 13 congenital, 27 idiopathic, 57 neuromuscular, 23 syndrome/tumor, and 5 kyphoscoliosis. Forty patients (32%) had postoperative MV >or=3 days. Independent factors likely requiring postoperative MV >or=3 days were neuromuscular scoliosis (P < 0.001) and FEV1 <40% predicted. Independent factors most likely were: neuromuscular scoliosis with preoperative FEV1 <40% predicted (P < 0.01). Independent factors most unlikely were: idiopathic scoliosis (P < 0.002). VC <60% predicted, IC <30 ml/kg, TLC <60% predicted, and MIP <60 cm H2O correlated with postoperative MV >or=3 days (P < 0.05). We found no association between RV and postoperative MV. FEV1 <40% predicted, VC <60% predicted, IC <30 ml/kg, TLC <60% predicted, MIP <60 cm H2O, and neuromuscular disease each correlated with prolonged postoperative MV. Neuromuscular disease or a preoperative FEV(1) <40% predicted were more likely, and older children with neuromuscular disease and FEV1 <40% predicted were most likely to require prolonged postoperative MV (P < 0.01). Clearly FEV1, and possibly VC, IC, TLC, and MIP, may increase accuracy in predicting the need for prolonged postoperative MV.

Preoperative polysomnograms and infant pulmonary function tests do not predict prolonged postoperative mechanical ventilation in children following scoliosis repair.

Our objective was the identification of children with scoliosis at higher risk of prolonged postoperative mechanical ventilation (MV) permits improved pre- and perioperative respiratory care to reduce postoperative complications. Pulmonary function testing (PFT) predicts prolonged postoperative MV in children who can reliably perform PFT, but some children cannot perform PFT. The objective of this study was to determine if polysomnography (PSG) or infant pulmonary function testing (IPFT) could predict prolonged postoperative MV (defined as MV >3 days) in children undergoing scoliosis surgery who could not reliably perform PFT. We studied 110 patients (age range, 10.8 +/- 4.9 [SD] years) who had preoperative PSG, and 18 patients (age range, 4.0 +/- 2.9 [SD] years) who had preoperative IPFT prior to undergoing any type of scoliosis repair by the Children's Hospital of Los Angeles Division of Orthopedic Surgery from January 1990- July 2001. The following information was reviewed and correlated: preoperative PSG parameters (baseline and nadir S(aO(2) ), baseline and peak P(ETCO(2) ), and apnea hypopnea index [AHI]), preoperative IPFT parameters (respiratory system compliance [C(rs)], respiratory system resistance [R(rs)], tidal volume [V(T)], and FRC), and length of postoperative MV. Twenty-seven patients (25%) who had PSG and 5 patients (28%) who had IPFT required postoperative MV >3 days. There was no association between baseline and nadir S(aO(2) )

Consensus statement on standard of care for congenital myopathies.

Recent progress in scientific research has facilitated accurate genetic and neuropathological diagnosis of congenital myopathies. However, given their relatively low incidence, congenital myopathies remain unfamiliar to the majority of care providers, and the levels of patient care are extremely variable. This consensus statement aims to provide care guidelines for congenital myopathies. The International Standard of Care Committee for Congenital Myopathies worked through frequent e-mail correspondences, periodic conference calls, 2 rounds of online surveys, and a 3-day workshop to achieve a consensus for diagnostic and clinical care recommendations. The committee includes 59 members from 10 medical disciplines. They are organized into 5 working groups: genetics/diagnosis, neurology, pulmonology, gastroenterology/nutrition/speech/oral care, and orthopedics/rehabilitation. In each care area the authors summarize the committee's recommendations for symptom assessments and therapeutic interventions. It is the committee's goal that through these recommendations, patients with congenital myopathies will receive optimal care and improve their disease outcome.

Safety, tolerability, and efficacy of high-frequency chest wall oscillation in pediatric patients with cerebral palsy and neuromuscular diseases: an exploratory randomized controlled trial.

Airway secretions and infections are common in cerebral palsy and neuromuscular diseases. Chest physiotherapy is standard therapy but effort is substantial. High-frequency chest wall oscillation is used in cystic fibrosis but tolerability and safety data in cerebral palsy and neuromuscular disease are limited. A prospective, randomized, controlled trial of high-frequency chest wall oscillation and standard chest physiotherapy was performed in participants with neuromuscular disease or cerebral palsy. Outcome measures included respiratory-related hospitalizations, antibiotic therapy, chest radiographs, and polysomnography. Care-givers were questioned regarding therapy adherence. A total of 28 participants enrolled, 23 completed (12 chest physiotherapy, mean study period 5 months). No adverse outcomes were reported. Adherence to prescribed regimen was higher with high-frequency chest wall oscillation (P = .036). Our data suggest safety, tolerability, and better compliance with high-frequency chest wall oscillation. Improvement in airway clearance may help prevent hospitalizations. Larger controlled trials are required to confirm these results.

The effect of scoliosis surgery on lung function in the immediate postoperative period.

STUDY DESIGN: Prospective, single-cohort study. OBJECTIVES: To determine the immediate change in pulmonary function test (PFT) in children following scoliosis surgery. SUMMARY OF BACKGROUND DATA: The number of pediatric scoliosis surgeries is increasing each year because of recent advances in spinal instrumentation, surgical techniques, and improved perioperative monitoring. Pulmonary function decreases immediately following scoliosis surgery, but the extent of this decrease is not well documented in pediatric patients. To use preoperative PFTs to assess the risk of postoperative complications, knowledge of the postoperative decline in PFT is necessary. METHODS: We measured preoperative and daily postoperative PFT in 24 children who had scoliosis surgery (age 12.7 +/- 2.7 [SD] years) from January 2002 to June 2003. There were 10 male and 14 female patients. Two (8%) patients had congenital scoliosis, 11 (46%) had idiopathic scoliosis, 9 (38%) had scoliosis due to a neuromuscular disease, and 2 (8%) had kyphoscoliosis. Fifteen (62%) patients had posterior spinal fusion (PSF), 5 (21%) had anterior spinal fusion (ASF), and 4 (17%) had both ASF and PSF performed. PFT parameters (forced expiratory volume in 1 second [FEV1], forced vital capacity [FVC], FEV1/FVC, and forced expiratory rate between 25% and 75% of FVC [FEF25%-75%]) were measured before surgery and daily after surgery by bedside spirometry until hospital discharge. RESULTS: PFT declined up to 60% after surgery. The PFT nadir is at 3 days. PFT values remained significantly decreased at 1 week, with values at about half of preoperative baseline. No patient required postoperative mechanical ventilation > or =3 days. There was no statistical significance between the degree of decline in PFT with etiology of either the scoliosis or the type of surgery performed. CONCLUSIONS: Our study found that patients are still at risk for postoperative complications as long as 1 week postoperatively and that PFTs do not return to near baseline until 1 to 2 months after surgery. The postoperative decrease in PFT should be considered during preoperative prediction of postoperative risk.