Alveolar recruitment for treatment of hypoxemia in acute respiratory failure

Abstract

Summary. The objective of this study was to select the optimal method of alveolar recruitment in patients with refractory hypoxemia. We used the APACHE II scale to assess the severity of the patient's status. We also investigated effects of alveolar recruitment on the blood gas exchange, the central haemodynamics and liquid balance in patients with acute respiratory failure. Patients involved in the study (n = 100) were divided into 3 groups. The control group (n = 45) was treated with conventional mechanical ventilation. A group with moderate hypoxemia (n = 32) was treated using a "sparing" alveolar recruitment technique with noninvasive monitoring of the arterial pressure, the heart beat rate, and SpO2. A group with severe hypoxemia (n = 23) was treated using an "aggressive" alveolar recruitment technique with noninvasive monitoring of the arterial pressure, the heart beat rate and SpO2, blood gases analysis, monitoring of the central haemodynamics, measurements of cardiac output (СО), cardiac index (СI), intrathoracic blood volume index (ITBVI), global end-diastolic volume index (GEDVI), extravascular lung water index (ELWI), and systemic vascular resistance (SVR) by the PICCO monitor. Both methods of alveolar recruitment significantly increased arterial oxygenation but did not worsen the haemodynamics. After the procedure, tidal volume and dynamic lung compliance increased. Alveolar recruitment did not influence on ELWI but decreased peak ITBVI and peak GEDVI. After the procedure of alveolar recruitment, these parameters returned to the baseline. Therefore, alveolar recruitment could improve arterial blood oxygenation and increase number of ventilated alveoli without any negative effects on haemodynamics.