Effects of Altered Intra-abdominal Pressure on the Upper Airway Collapsibility in a Porcine Model / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Obstructive sleep apnea is strongly associated with obesity, particularly abdominal obesity common in centrally obese males. Previous studies have demonstrated that intra-abdominal pressure (IAP) is increased in morbid obesity, and tracheal traction forces may influence pharyngeal airway collapsibility. This study aimed to investigate that whether IAP plays a role in the mechanism of upper airway (UA) collapsibility via IAP-related caudal tracheal traction.</p><p><b>METHODS</b>An abdominal wall lifting (AWL) system and graded CO2pneumoperitoneum pressure was applied to four supine, anesthetized Guizhou miniature pigs and its effects on tracheal displacement (TD) and airflow dynamics of UA were studied. Individual run data in 3 min obtained before and after AWL and obtained before and after graded pneumoperitoneum pressure were analyzed. Differences between baseline and AWL/graded pneumoperitoneum pressure data of each pig were examined using a Student's t-test or analysis of variance.</p><p><b>RESULTS</b>Application of AWL resulted in decreased IAP and significant caudal TD. The average displacement amplitude was 0.44 mm (P < 0.001). There were three subjects showed increased tidal volume (TV) (P < 0.01) and peak inspiratory airflow (P < 0.01); however, the change of flow limitation inspiratory UA resistance (Rua) was not significant. Experimental increased IAP by pneumoperitoneum resulted in significant cranial TD. The average displacement amplitude was 1.07 mm (P < 0.001) when IAP was 25 cmH2O compared to baseline. There were three subjects showed reduced Rua while the TV increased (P < 0.01). There was one subject had decreased TV and elevated Rua (P < 0.001).</p><p><b>CONCLUSIONS</b>Decreased IAP significantly increased caudal TD, and elevated IAP significantly increased cranial TD. However, the mechanism of UA collapsibility appears primarily mediated by changes in lung volume rather than tracheal traction effect. TV plays an independent role in the mechanism of UA collapsibility.</p>

Effect of an emergency department sepsis protocol on the care of septic patients admitted to the intensive care unit.

OBJECTIVE: We sought to determine whether the implementation of a sepsis protocol in a Canadian emergency department (ED) improves care for the subset of patients admitted to the intensive care unit (ICU). METHODS: After implementing a sepsis protocol in our ED we used an ICU database and chart review to compare various time-dependent end points and outcomes between a historical control year and the first year after implementation. We re-viewed the charts of all patients admitted to the ICU within 24 hours of ED admission with a primary or other diagnosis of sepsis, severe sepsis or septic shock, who met criteria for early goal-directed therapy within the first 6 hours of their ED stay. RESULTS: We compared 29 patients from the control year with 30 patients from the year after implementation of our sepsis protocol. We found that patients treated during the postintervention year had improvements in time to antibiotics (4.2 v. 1.0 h, difference = -3.2 h, 95% CI -4.8 to -2.0), time to central line placement (above the diaphragm) (11.6 v. 3.2 h, difference = -8.4 h, 95% CI -12.1 to -4.7), time to arterial line placement (7.5 v. 2.3 h, difference = -5.2 h, 95% CI -7.4 to -3.0), and achievement of central venous pressure and central venous oxygen saturation goals (11.1 v. 5.1 h, difference = -6.0 h, 95% CI -11.03 to -1.71, and 13.1 v. 5.5 h, difference = -7.6 h, 95% CI -11.97 to -3.16, respectively). There were no statistically significant differences in ICU length of stay, hospital length of stay or mortality (31.0% v. 20.0%, difference = -11.0%, 95% -33.1% to 11.1%). CONCLUSION: Implementation of an ED sepsis protocol im-proves care for patients with severe sepsis and septic shock.