Mechanical ventilation promotes redox status alterations in the diaphragm.

Oxidative stress is an important mediator of diaphragm muscle atrophy and contractile dysfunction during prolonged periods of controlled mechanical ventilation (MV). To date, specific details related to the impact of MV on diaphragmatic redox status remain unknown. To fill this void, we tested the hypothesis that MV-induced diaphragmatic oxidative stress is the consequence of both an elevation in intracellular oxidant production in conjunction with a decrease in the antioxidant buffering capacity. Adult rats were assigned to one of two experimental groups: 1) control or 2) 12 h of MV. Compared with controls, diaphragms from MV animals demonstrated increased oxidant production, diminished total antioxidant capacity, and decreased glutathione levels. Heme oxygenase-1 (HO-1) mRNA and protein levels increased (23.0- and 5.1-fold, respectively) following MV. Thioredoxin reductase-1 and manganese superoxide dismutase mRNA levels were also increased in the diaphragm following MV (2.4- and 1.6-fold, respectively), although no change was detected in the levels of either protein. Furthermore, copper-zinc superoxide dismutase and glutathione peroxidase mRNA were not altered following MV, although protein content decreased -1.3- and -1.7-fold, respectively. We conclude that MV promotes increased oxidant production and impairment of key antioxidant defenses in the diaphragm; collectively, these changes contribute to the MV-induced oxidative stress in this key inspiratory muscle.

Patients presenting with birth plans in a military tertiary care hospital: a descriptive study of plans and outcomes.

OBJECTIVES: This study evaluates what type of patient prepares a birth plan, identifies common requests made, and determines how closely these are followed during labor. METHODS: Patients who were admitted in labor with birth plans during a 3.5-year period were identified. Birth plans were analyzed, and common requests were recorded. Delivery records were reviewed, and outcomes were recorded. This study was approved by the hospital institutional review board. RESULTS: Sixty-seven birth plans with delivery outcomes were available for review. The mean maternal age was 31 years, the median parity was 0, and 70% of patients had a college degree. The most common requests were to walk during labor (84%), to avoid episiotomy (82%), and to have no epidural (62%). Seventy-five percent of patients had spontaneous vaginal deliveries, and 19% had cesarean sections; the epidural use rate was 59%. CONCLUSIONS: Patients with birth plans were generally older and well-educated and, despite plans to avoid an epidural, most patients changed their minds.