COMPARATIVE STUDY BETWEEN THE EFFECT OF VOLUME-CONTROLLED VENTILATION AND PRESSURE CONTROLLED VENTILATION VOLUME GUARANTEED ON GAS EXCHANGE AND RESPIRATORY DYNAMICS DURING ONE-LUNG VENTILATION

Abstract

ABSTRACT Background: Impairment of gas exchange is a common problem during one lung ventilation (OLV) with a hazardous effect on morbidity and mortality. The current study compares the effect of volume-controlled ventilation (VCV) versus pressure-controlled ventilation volume guaranteed (PCV-VG) on gas exchange during OLV. Settings and Design: This study was a prospective randomized study. Methods: The study was carried out on 30 adult patients who were randomly assigned to two groups. Group VCV: VCV was performed throughout the operation. Group PCV-VG: PCV-VG was performed throughout the operation. Haemodynamic parameters ((HR), MAP), and (CVP)), blood gas analysis, and PaO2/FiO2 were recorded: before induction of anaesthesia (T0); during TLV (T1); ½ an hour after OLV (T2); 1 h after OLV (T3); 20 minutes after resuming TLV (T4); 6, 12, and 24 hours after surgery (T5, 6, and T7). (Ppeak), (Pmean) and (Cdyn) were recorded during (T1, 2, 3, and T4) time intervals. TNFα level was measured in venous Samples in the following times: (1) before induction of anaesthesia (T0); (2) Directly after surgery (T1); (3) 5th postoperative day (T2). The patients were followed for 5 days for recording of PPCs. Results: PCV-VG ventilation leads to a significant decrease in Ppeak and Pmean and significant increase in Cdyn (P ≤ 0.05). However, it had no effect on intra- and postoperative oxygenation values. Conclusion: PCV-VG is superior to VCV as regard respiratory dynamics during one lung ventilation (OLV), while it does not differ as regard items of gas exchange, inflammatory response and PPCs. Abbreviations: OLV: one lung ventilation; TLV: two lung ventilation; VCV: volume-controlled ventilation; PCV-VG: pressure-controlled ventilation volume guaranteed; PaO2: arterial oxygen tension; FiO2: fraction of inspired oxygen; Ppeak: Peak inspiratory pressure; Pmean: mean inspiratory pressure; Cdyn: dynamic compliance TNFα: Tumour necrosis factor α; PPCs: postoperative pulmonary complications.