Positive end expiratory pressure titrated by transpulmonary pressure improved oxygenation and respiratory mechanics in acute respiratory distress syndrome patients with intra-abdominal hypertension

Background Intra-abdominal hypertension （IAH） is common in acute respiratory distress syndrome （ARDS） patients and when resulting in decrease of chest wall compliance will weaken the effect of positive end expiratory pressure （PEEP）. We investigated the effect of PEEP titrated by transpulmonary pressure （Ptp） on oxygenation and respiratory mechanics in ARDS patients with IAH compared with PEEP titrated by ARDSnet protocol. Methods ARDS patients admitted to the intensive care unit （ICU） of the Zhongda Hospital were enrolled. Patients were ventilated with volume control mode with tidal volume of 6 ml/kg under two different PEEP levels titrated by Ptp method and ARDSnet protocol. Respiratory mechanics, gas exchange and haemodynamics were measured after 30 minutes of ventilation in each round. IAH was defined as intra-abdominal pressure of 12 mmHg or more, Results Seven ARDS patients with IAH and 8 ARDS patients without IAH were enrolled. PEEP titrated by Ptp were significant higher than PEEP titrated by ARDSnet protocol in both ARDS patients with IAH （（17.3±2.6）cmH20 vs. （6.3±1.6） cmH2O and without IAH （（9.5±2.1） cmH2O vs. （7.8±1.9） cmH2O）. Arterial pressure of O2/fraction of inspired oxygen （PaO2/ FiO2） was much higher under PEEP titrated by Ptp when compared with PEEP titrated by ARDSnet protocol in ARDS patients with IAH （（27.2±4.0） cmHg vs. （20.9± 5.0） cmHg. But no significant difference of PaO2/FiO2 between the two methods was found in ARDS patients without IAH. In ARDS patients with IAH, static compliance of lung and respiratory system were higher under PEEP titrated by Ptp than by ARDSnet protocol. In ARDS patients with IAH, central venous pressure （CVP） was higher during PEEP titrated by Ptp than by ARDSnet protocol. Conclusion Positive end expiratory pressure titrated by transpulmonary pressure was higher than PEEP titrated by ARDSnet protocol and improved oxygenation and respiratory mechanics in ARDS patients with IAH.

Anesthetic management for the patients with cardiac transplant

With the advancement of medical technique and application of the new immunosuppressant agents, cardiac transplantation has become an effective treatment for end-stage heart disease caused by different reasons. The orthotopic procedure has been performed in many countries nowadays. Whether it is successful or not mainly depends on harvesting the denoted heart, operative technique and perioperative management.