Time to Mobility Is Associated With Pulmonary Complications in Patients With Spine Fractures

INTRODUCTION

Treatment of spine fractures may require periods of prolonged immobilization which prevents effective pulmonary toileting. We hypothesized that patients with longer time to mobilization, as measured by time to first physical therapy (PT) session, would have higher pulmonary complications.

METHODS

We performed a retrospective review of all trauma patients with cervical and thoracolumbar spinal fractures admitted to a level 1 trauma center over a 12-month period. Demographic data collection included age, gender, BMI, pulmonary comorbidities, concomitant rib fractures, admission GCS, Injury Severity Score (ISS), GCS at 24 h, treatment with cervical or thoracolumbar immobilization, and time to first PT evaluation. The primary outcome was the presence of any one of the following complications: unplanned intubation, pneumonia, or mortality at 30 days. Multivariable logistic regression analysis was used to assess significant predictors of pulmonary complication.

RESULTS

In total, 491 patients were identified. In terms of overall pulmonary complications, 10% developed pneumonia, 13% had unplanned intubation, and 6% died within 30 days. In total, 19% developed one or more complication. Overall, 25% of patients were seen by PT <48 h, 33% between 48 and 96 h, 19% at 96 h to 1 week, and 7% > 1 week. Multivariable logistic regression analysis showed that time to PT session (OR 1.010, 95% CI 1.005-1.016) and ISS (OR 1.063, 95% CI 1.026-1.102) were independently associated with pulmonary complication.

CONCLUSION

Time to mobility is independently associated with pulmonary complications in patients with spine fractures.

Physiological and metabolic characteristics of novel double-mutant female mice with targeted disruption of both growth hormone-releasing hormone and growth hormone receptor

Mice with disruptions of growth hormone-releasing hormone (GHRH) or growth hormone receptor (GHR) exhibit similar phenotypes of prolonged lifespan and delayed age-related diseases. However, these two models respond differently to calorie restriction indicating that they might carry different and/or independent mechanisms for improved longevity and healthspan. In order to elucidate these mechanisms, we generated GHRH and GHR double-knockout mice (D-KO). In the present study, we focused specifically on the characteristics of female D-KO mice. The D-KO mice have reduced body weight and enhanced insulin sensitivity compared to wild-type (WT) controls. Growth retardation in D-KO mice is accompanied by decreased GH expression in pituitary, decreased circulating IGF-1, increased high-molecular-weight (HMW) adiponectin, and leptin hormones compared to WT controls. Generalized linear model-based regression analysis, which controls for body weight differences between D-KO and WT groups, shows that D-KO mice have decreased lean mass, bone mineral density, and bone mineral content, but increased adiposity. Indirect calorimetry markers including oxygen consumption, carbon dioxide production, and energy expenditure were significantly lower in D-KO mice relative to the controls. In comparison with WT mice, the D-KO mice displayed reduced respiratory exchange ratio (RER) values only during the light cycle, suggesting a circadian-related metabolic shift toward fat utilization. Interestingly, to date survival data suggest extended lifespan in D-KO female mice.