Positive end-expiratory pressure improves oxygenation inducing ventral-to-dorsal tidal ventilation redistribution: an electrical impedance tomography study (original) (raw)
CHEST Journal, 2012
ABSTRACT SESSION TYPE: Physiology/PFTs/ Rehabilitation IPRESENTED ON: Sunday, October 21, 2012 at 01:15 PM - 02:45 PMPURPOSE: Respiratory failure requiring mechanical ventilation is an uncommon event during pregnancy. Physiologic changes of pregnancy and concerns for fetal wellbeing complicate the use of Mechanical Ventilation. The purpose of this study was to describe clinical characteristics of obstetric patients requiring Mechanical Ventilation, and their maternal and perinatal outcomes.METHODS: Observational retrospective study of all obstetric patients admitted to the Intensive Care Unit (ICU) at Rafael Calvo Maternity Hospital in Cartagena (Colombia), requiring Mechanical Ventilation for >24 hours between September, 2005 and December, 2011. Records were reviewed for demographic, diagnosis on admission and throughout stay, medical history, length of stay, perinatal and maternal mortality and ventilatory parameters.RESULTS: There were 750 ICU admissions during pregnancy or up to 6 weeks from the conclusion of pregnancy during the study period. A total of 131 (17.4 %) of patients required ventilatory support (32 during pregnancy), for a total of 822 ventilation days. The mortality rate was 23.6% (31 deaths) in Mechanical Ventilation patients. APACHE II was 8 (IQR 6-12) in non-ventilated patients and 14 (IQR 10-21) in ventilated patients (P<0.001). The median age was 24.3 years (SD±6.6). The median duration on mechanical ventilation was 3 days (IQR 1-6). Mean length of stay in ICU was 11.02 days (SD± 8.4). The most common diagnoses on admission were obstetric hemorrhage (36.2%) and gestational hypertensive disorders (29.8%). Volume-cycled was the most frequently used mode of ventilation (67/115 patients), with a mean tidal volume of 449.07mL (SD±90.7), and a mean Positive End-Expiratory Pressure (PEEP) of 7 cmH2O(SD± 2.4). Perinatal mortality (stillbirths and miscarriages) in ventilated mothers was 24.4%, and 15.4% in non-ventilated obstetric ICU patients (P<0.001).CONCLUSIONS: Maternal severity and perinatal mortality are significantly elevated in obstetric patients requiring mechanical ventilation.CLINICAL IMPLICATIONS: Given the elevated risk of mortality in obstetric patients requiring mechanical ventilation, aggressive therapeutic measures should be instituted.DISCLOSURE: The following authors have nothing to disclose: Jose Rojas-Suarez, Carmelo Dueñas, Angel Paternina, Jezid Miranda, Eliana Castillo, Ghada BourjeilyNo Product/Research Disclosure InformationUniversidad de Cartagena, Cartagena, Colombia.