IntroductionMost patients are readily liberated from mechanical ventilation (MV) support, however, 10% - 15% of patients experience failure to wean (FTW). FTW patients account for approximately 40% of all MV days and have significantly worse clinical outcomes. MV induced inspiratory muscle weakness has been implicated as a contributor to FTW and recent work has documented inspiratory muscle weakness in humans supported with MV.MethodsWe conducted a single center, single-blind, randomized controlled trial to test whether inspiratory muscle strength training (IMST) would improve weaning outcome in FTW patients. Of 129 patients evaluated for participation, 69 were enrolled and studied. 35 subjects were randomly assigned to the IMST condition and 34 to the SHAM treatment. IMST was performed with a threshold inspiratory device, set at the highest pressure tolerated and progressed daily. SHAM training provided a constant, low inspiratory pressure load. Subjects completed 4 sets of 6-10 training breaths, 5 days per week. Subjects also performed progressively longer breathing trials daily per protocol. The weaning criterion was 72 consecutive hours without MV support. Subjects were blinded to group assignment, and were treated until weaned or 28 days.ResultsGroups were comparable on demographic and clinical variables at baseline. The IMST and SHAM groups respectively received 41.9 ± 25.5 vs. 47.3 ± 33.0 days of MV support prior to starting intervention, P = 0.36. The IMST and SHAM groups participated in 9.7 ± 4.0 and 11.0 ± 4.8 training sessions, respectively, P = 0.09. The SHAM group's pre to post-training maximal inspiratory pressure (MIP) change was not significant (-43.5 ± 17.8 vs. -45.1 ± 19.5 cm H2O, P = 0.39), while the IMST group's MIP increased (-44.4 ± 18.4 vs. -54.1 ± 17.8 cm H2O, P < 0.0001). There were no adverse events observed during IMST or SHAM treatments. Twenty-five of 35 IMST subjects weaned (71%, 95% confidence interval (CI) = 55% to 84%), while 16 of 34 (47%, 95% CI = 31% to 63%) SHAM subjects weaned, P = .039. The number of patients needed to be treated for effect was 4 (95% CI = 2 to 80).ConclusionsAn IMST program can lead to increased MIP and improved weaning outcome in FTW patients compared to SHAM treatment.Trial RegistrationClinicalTrials.gov: NCT00419458

The purpose of this review is to summarize literature that describes the impact of exercise on health and physical function among children during and after treatment for cancer. Relevant studies were identified by entering the following search terms into Pubmed: aerobic training; resistance training; stretching; pediatric; children; AND cancer. Reference lists in retrieved manuscripts were also reviewed to identify additional trials. We include fifteen intervention trials published between 1993 and 2011 that included children younger than age 21 years with cancer diagnoses. Nine included children with an acute lymphoblastic leukemia (ALL) diagnosis, and six children with mixed cancer diagnoses. Generally, interventions tested were either in-hospital supervised exercise training or home based programs designed to promote physical activity. Early evidence from small studies indicates that the effects of exercise include increased cardiopulmonary fitness, improved muscle strength and flexibility, reduced fatigue and improved physical function. Generalizations to the entire childhood cancer and childhood cancer survivor populations are difficult as most of the work has been done in children during treatment for and among survivors of ALL. Additional randomized studies are needed to confirm these benefits in larger populations of children with ALL, and in populations with cancer diagnoses other than ALL.

O ver the last 3 decades, therapeutic progress has resulted in a growing population of survivors of childhood cancer. In 2006, there were Ͼ 11 million cancer survivors in the United States, three times the number of survivors in 1971. 1 The 5-year survival rate for children diagnosed with cancer is approaching 85%, 2 and an estimated one in 570 individuals in the United States between the ages of 20 and 34 is a survivor of childhood cancer. 3 Unfortunately, increased survival rates are not without consequences. There is substantial evidence Background: The purpose of this article is to summarize the literature that documents the longterm impact of cancer treatment modalities on pulmonary function among survivors of cancer and to identify potential areas for further research. Methods: Systematic reviews of clinical trials, observational studies, case series, and review articles were conducted. Articles were limited to the studies that discussed pulmonary toxicity or late effects among pediatric cancer survivors and to follow-up investigations that were conducted a minimum of 2 years after completion of cancer-related treatment or 1 year after hematopoietic stem cell transplant. Results: Sixty publications (51 clinical studies/reports and nine reviews) published from January 1970 to June 2010 in PubMed met the inclusion criteria. Data showed an association between radiotherapy, alkylating agents, bleomycin, hematopoietic stem cell transplant, and thoracic surgery and pulmonary toxicity, as well as possible interactions among these modalities. Conclusions: Pulmonary toxicity is a common long-term complication of exposure to certain anticancer therapies in childhood and can vary from subclinical to life threatening. Pulmonary function and associated loss of optimal exercise capacity may have adverse effects on long-term quality of life in survivors. Lung function diminishes as a function of normal aging, and the effects of early lung injury from cancer therapy may compound these changes. The information presented in this review is designed to provide a stimulus to promote both observational and interventional research that expands our knowledge and aids in the design of interventions to prevent or ameliorate pulmonary late effects among survivors of childhood cancer. CHEST 2011; 140(4):881-901Abbreviations: ALL 5 acute lymphoblastic leukemia; BCNU 5 carmustine; CCNU 5 lomustine; D lco 5 diffusing capacity of the lung for carbon monoxide; GVHD 5 graft-vs-host disease; gy 5 gray; HL 5 Hodgkin's lymphoma; HSCT 5 hematopoietic stem cell transplant; NHL 5 non-Hodgkin's lymphoma; PFT 5 pulmonary function testing; TLC 5 total lung capacity

Effect of inspiratory muscle strength training on inspiratory motor drive and RREP early peak components.

Cardiothoracic surgery results in rapid changes in human diaphragm gene expression in the operating room, including genes related to stress response, inflammation, redox regulation, and proteolysis. These results may provide insight into diaphragm muscle biology after prolonged cardiothoracic procedures.