A new approach to the selection of respiratory support methods in pulmonology

Abstract

The aim of the study was to evaluate the efficacy of the new approach to the selection of respiratory support methods based on the analysis of arterial blood acid-base balance and gas composition in treatment of severe community-acquired pneumonia complicated by acute respiratory failure. Materials and Methods. Conventional pulse oximetry (SрО2) was used (G40 Patient Monitor), arterial blood acid-base balance and gas composition were analyzed (EasyStat device) to detect hypoxemia. Respiratory support of three types was carried out: 1) oxygen therapy (О2-therapy) with the use of oral nasal oxygen masks; 2) non-invasive lung ventilation (VENTIlogic 2 and BiPAP Vision devices); 3) artificial lung ventilation (Engström Carestation device). The work was carried out in two sequential stages. At the first stage, a respiratory support method was selected according to the results of pulse oximetry (SрО2). At the second stage, a respiratory support method was selected on the basis of arterial blood acid-base balance and gas composition indices (рО2, pH, рCО2). Recovery of pulse oximetry indices, arterial blood acid-base balance, and gas composition indices as well as presence of positive clinical dynamics were considered to be criteria of treatment efficacy. Results. Comparative analysis of the results of the used methods has provided the possibility to develop the algorithm of choosing the respiratory support method in severe community-acquired pneumonia on the basis of arterial blood acid-base balance and gas composition with pulse oximetry indices equalling 91.0±0.8%. On admission of a patient to the intensive care unit, oxygen therapy is administered at рН≥7.3; рO2>60 mm Hg; рСО2≤45 mm Hg; non-invasive lung ventilation — at pH<7.3; рO2≤60 mm Hg; рСО2≤45 mm Hg; artificial lung ventilation — at pH<7.3; рO2<60 mm Hg; рСО2>45 mm Hg. Selection of respiratory support based on blood acid-base balance and gas composition indices without taking into account pulse oximetry indices allows us to increase treatment efficacy, reduce the period of stay in the intensive care unit by 1.5 times, mortality — by 4.3 times.