Comparıson of Two Dıfferent Peep Levels in One Lung Ventilation

Abstract

Objective: This study aims to analyze the effects of two different positive end-expiratory pressure (PEEP) levels during single lung ventilation with low tidal volume (TV) on respiration and hemodynamics in patients undergoing thoracotomy. Material and Methods: After the Hospital Education Planning Board approval and written consent were obtained 40 patients scheduled for thoracotomy were enrolled in the study. When all patients were intubated with double-lumen endotracheal tube and one-lung ventilation (OLV) was initiated, the patients were randomized into two groups. Group 1 (n: 20) consisted of patients who underwent lung ventilation with 6 ml/kg TV and 5 cm H20 PEEP; and Group 2 (n: 20) consisted of patients who underwent lung ventilation with 6 mU kg TV and 10 cm H2O PEEP. Arterial blood gas samples were obtained from the patients during the study, and mean arterial pressure, heart rate, partial oxygen pressure (pO2), partial carbondioxide pressure (pCO2), peak airway pressures (PIP), plateau pressure values were recorded at 7 different time points namely TO: Supine position, before the induction, T1: double lung ventilation after induction, T2: OLV 15 minutes, T3: OLV 30 minutes, T4: OLV 45 minutes, T5: pre-extubation, supine position, T6: Postoperative 6th hour. Results: Mean arterial pressure and heart rate values were significantly lower at Tl, T2, T3 ve T4 time points in Group 2; however, this decrease was within physiological limit. Group 2 patients had significantly higher PaO2 and lower PaCO2 values. At time points of T2, T3 and T4 when the patients were under OLV, PiP and plateau pressures in Group 2 patients were significantly higher (p<0.05). Conclusion: It was concluded that delivery of low tidal volume and 10 cm H2O PEEP to the ventilated lung during thoracotomy made positive contributions to oxygenation without any adverse effects on hemodynamic, and respiratory mechanisms.