Assessing air travel safety in neuromuscular disease: standard versus prolonged hypoxic challenge tests.

PURPOSE: The hypoxic challenge test (HCT) is used to evaluate safety for air travel in individuals with respiratory disease by breathing in 15% oxygen for 20 min. Our aim was to determine if a prolonged HCT, lasting 120 min, identified more individuals with neuromuscular disease at potential risk than the standard HCT lasting 20 min. METHODS: This was a cross-sectional study. All of the clinical testing took place at SickKids, Toronto, Canada. Patients were included in the study if they had a diagnosis of NMD, greater than 6 years of age, resting oxygen saturation ≥ 94%, and partial pressure of carbon dioxide (pCO2) ≤ 45 mmHg. Notable exclusion criteria were left ventricular ejection fraction < 30%, presence of a tracheostomy, and use of non-invasive ventilation for more than 12 h daily. Participants underwent a standard HCT as well as the prolonged HCT on the same day. RESULTS: Twenty-three patients consented to the study. One patient was withdrawn because he was unable to follow the study procedures. The 22 study participants had a mean age of 14.9 years (standard deviation (SD) of 5 years). Seventeen (77%) participants were male. Two participants were withdrawn on the day of testing due to hypercapnia. Twenty participants completed the standard and prolonged HCTs. None of the participants had a positive standard or prolonged HCT. CONCLUSION: Our results suggest that performing a standard or prolonged HCT may, in fact, not be of clinical utility in individuals with less severe NMD.

The Impact of Pulmonary Rehabilitation on Chronic Pain in People with COPD.

Chronic pain affects up to 88% of people with chronic obstructive pulmonary disease (COPD) and has been associated with comorbidities. However, with pain not evaluated during pulmonary rehabilitation (PR) assessments, it is unclear whether PR impacts pain intensity and coping ability. This study aimed to 1) determine the effect of PR on pain qualities, coping behavior and psychological symptoms in those with COPD and chronic pain; and 2) assess the impact of PR on exercise capacity and quality of life in individuals with COPD and chronic pain compared to those without pain. Patients with COPD and comorbidities enrolling in outpatient PR were assessed for chronic pain. Those with chronic pain completed the Brief Pain Inventory, Coping Strategies Questionnaire-24, Fear Avoidance Behavior Questionnaire and measures of anxiety and depression. Changes in HRQOL and 6-minute walk distance (6MWD) following PR were compared between participants with and without chronic pain. Thirty-four participants with chronic pain and 34 participants without pain were included (mean ± SD, FEV1 47 ± 19% predicted). In those with chronic pain, PR did not affect pain intensity (median[IQR] pre/post PR 3[2-5] vs. 4[2-6] points, p = 0.21), anxiety (7[2-9] vs. 5[3-8] points, p = 0.82) or depression (4[2-8] vs. 3[1-6] points, p = 0.38) and did not change pain coping strategies. Both groups improved in 6MWD (mean difference [95% CI] 17[-39 to 72] m), and those without pain had greater improvement in mastery (p = 0.013). PR was effective in patients with moderate to severe COPD whether or not they reported chronic pain at the time of their initial assessment.

Cardiac management of ventilator-assisted individuals with Duchenne muscular dystrophy.

As life expectancy of patients with Duchenne muscular dystrophy (DMD) has increased to the 5th decade, in part due to improved ventilatory support, cardiomyopathy is projected to increase as a cause of death. International guidelines recommend an annual assessment of cardiac function and initiation of appropriate pharmacological treatment. We conducted an audit of the cardiac management in patients with DMD requiring ventilatory support and reported a case series of the collated cardiac investigations. Patients with DMD requiring ventilatory support were included in the study. The date of the last electrocardiogram (ECG), echocardiogram (ECHO), cardiology review and pharmacological management were retrieved from the medical records. If an annual cardiac assessment had not been performed this was requested and the latest ECGs and ECHO reports were collated. A total of 30 patients with DMD (29 males, mean (SD) age of 30 (7) years) met the inclusion criteria. Although there was ECG and ECHO documentation in 24 and 21 individuals, respectively, it was only recent in 10 and 6 individuals. In all, 60% of patients had been assessed by a cardiologist, but only 10% within the last year. Over half of the patients failed to attend their new appointments. From the available results, 18 of the 19 patients had an abnormal ECG, 11 of the 16 patients had left ventricular (LV) impairment and 55% of patients had a change in prescription following cardiac investigations. There is a need for a coordinated cardiorespiratory approach towards adult patients with DMD. Over a third of patients had normal LV function suggesting that cardiomyopathy is not inevitable in this group.

Ondine's curse: anesthesia for laparoscopic implantation of a diaphragm pacing stimulation system.

PURPOSE: Central alveolar hypoventilation syndrome (CAHS) is a rare disease characterized by the loss of autonomic control of breathing. This condition causes hypoventilation and obstruction during sleep. Throughout their lives, these patients require ventilatory assistance by means of positive pressure ventilation to their lungs via mask, tracheotomy, or other means, such as phrenic nerve pacers. The diaphragm pacing stimulation system (DPSS) is a new treatment where electrodes are implanted into the diaphragm and cause contraction on stimulation. The DPSS has been used successfully in tetraplegic patients and patients suffering from amyotrophic lateral sclerosis (ALS). It has been shown to improve quality of life and to extend survival in patients with advanced respiratory muscle weakness. In our case, we describe the perioperative management of an adult patient with acquired CAHS who presented for laparoscopic DPSS insertion. CLINICAL FEATURES: Our patient was a 50-yr-old female who developed CAHS at age thirteen after contracting encephalitis. Since the onset of her disease, she had been managed with positive pressure ventilation to her lungs via mask. Due to her longstanding disease, she presented with pulmonary hypertension and cor pulmonale and was scheduled for laparoscopic DPSS implantation. Our anesthetic technique included a total intravenous technique with remifentanil and propofol, and her trachea was intubated without the use of muscle relaxants. The pacemakers were switched on when the patient emerged from anesthesia, which provided her with ventilatory support and allowed us to extubate her trachea. CONCLUSION: We present the successful anesthetic management of an adult patient with CAHS undergoing laparoscopic DPSS insertion.

A transition program to adult health services for teenagers receiving long-term home mechanical ventilation: A longitudinal qualitative study.

OBJECTIVE: Adolescents receiving long-term home mechanical ventilation (HMV) who survive into adulthood must transition to adult health care services. Lack of transition readiness is reported to result in poor health outcomes. The objective of this study is to explore longitudinally the pediatric-to-adult health care transition experience involving a transition program for adolescents receiving HMV including transition readiness, barriers, facilitators, and modifiable features. DESIGN: A prospective qualitative longitudinal interview study of adolescent and family caregiver dyads recruited through a pediatric-to-adult HMV transition program jointly established by two collaborating health centers: The Hospital for Sick Children and West Park Healthcare Centre in Toronto, Canada. Eligible dyads were interviewed at three time points: pretransition, transition, and 12-months posttransition. Interviews were transcribed verbatim and analyzed using directed content analysis methods. RESULTS: Ventilator-assisted adolescents (VAAs) and caregiver participants perceived a lack of transition readiness in their ability to manage health communication and coordination across multiple adult providers. Transition facilitators included early transition discussion, opportunities for VAAs to speak directly with HMV providers during appointments, receipt of print informational materials regarding adult services, and a joint pediatric-adult team handover meeting. Modifiable transition barriers included lack of other specialist referrals, insufficient information about adult homecare service funding, and limited involvement of family doctors. Unresolved transition barriers resulted in perceptions of service fragmentation. CONCLUSIONS: Although the pediatric-to-adult HMV transition program conferred benefits service fragmentation was perceived. Transition barriers may be overcome through early planning and staged transition with all specialists, community providers, and the family and adolescent working in collaboration.

Pulmonary rehabilitation and pharmacotherapy.

Though pulmonary rehabilitation can have potent effects on exercise capacity and quality of life in chronic obstructive pulmonary disease (COPD), not all patients benefit to the same degree. Enabling patients to achieve higher training intensities may improve exercise capacity. Adding pharmacological agents to target the abnormal ventilatory mechanics or skeletal muscle dysfunction may enhance the effects of exercise training. This review discusses the rationale and clinical evidence supporting the use of pharmacological adjuncts during the course of pulmonary rehabilitation.

Multidrug-resistant tuberculosis: Treatment and outcomes of 93 patients.

BACKGROUND: Tuberculosis (TB) remains a leading cause of death worldwide and the emergence of multidrug-resistant TB (MDR TB) poses a threat to its control. There is scanty evidence regarding optimal management of MDR TB. The majority of Canadian cases of MDR TB are diagnosed in Ontario; most are managed by the Tuberculosis Service at West Park Healthcare Centre in Toronto. The authors reviewed 93 cases of MDR TB admitted from January 1, 2000 to December 31, 2011. RESULTS: Eighty-nine patients were foreign born. Fifty-six percent had a previous diagnosis of TB and most (70%) had only pulmonary involvement. Symptoms included productive cough, weight loss, fever and malaise. The average length of inpatient stay was 126 days. All patients had a peripherally inserted central catheter for the intensive treatment phase because medications were given intravenously. Treatment lasted for 24 months after bacteriologic conversion, and included a mean (± SD) of 5 ± 1 drugs. A successful outcome at the end of treatment was observed in 84% of patients. Bacteriological conversion was achieved in 98% of patients with initial positive sputum cultures; conversion occurred by four months in 91%. CONCLUSIONS: MDR TB can be controlled with the available anti-TB drugs.