Author Design Patients Mechanical Ventilation Procedure OxygenationParameter Outcome Reis (59) RCT N = 69 1. Conventional 2. Early OLV 3. Late OLV CABG/valve Sp02 -CLV: 37% hypoxic on 3rd day after extubation. -OLV: none Celebi (47) RCT N = 60 1. CPAP of 40 2. PEEP of 20 3. PEEP of 5 CPB PaO2/FIO2 Pa02/FiO2 higher in CPAP 40, and PEEP 20 cm H20 groups compared with PEEP of 5 group (30) Reis (45) RCT N = 62 1. Conventional 2. Early OLV 3. Late OLV CABG/valve NA -↓IL-8 more rapidly in OLV groups -↓Il-10 more rapidly only in early OLV Dyhr (46) RCT N = 16 1. RM→PEEP 1 cm H20 >LIP 2. RM only CABG Pa02 -Pa02 16 +/- 16 KPa -No change from baseline CLV; conventional lung ventilation, OLV; open lung ventilation, 1,2,3; refer to group numbers, LIP; lower inflection point, PEEP; positive end expiratory pressure, RM; recruitment maneuver, PaO2; partial pressure of oxygen.

Table 1: Studies of PEEP in Patients Undergoing Cardiopulmonary Bypass.