To analyze the impact of positive pressure on acute postoperative recovery after Coronary Artery Bypass Surgery (CABG).
60 patients who underwent elective CABG, were randomized into 3 groups. Control group was submitted to breathing exercises and early walking. The IPPB+PEEP group was submitted to the same exercises described for the control group, in addition to IPPB (25 cmH2O-10 breaths/minute over a ten minute period and in association with PEEP at 10 cmH2O). The IPPB group was submitted to the same procedure of the second group excluding the PEEP. The parameters evaluated were forced vital capacity (FVC), Pulse oximetry (SaO2), Pain score (visual analogue scale) and Chest Radiography (atelectasis and pleural effusion). All these data had been collected in preoperative and from the first to the sixth postoperative day. Atelectasis was graded using a 0 to 4 scale (0=no atelectasis; 4=lobar atelectasis). Pleural effusion was graded using a 0-3 scale (0=no pleural effusion; 3=effusion occupying more than two intercostal spaces).
The results were expressed as mean ±standard errors(em). In all groups FVC and SaO2 decreased more than 50% (p<0,05), in the first postoperative day, improving with time. In the 6th day, the FVC in the IPPB+PEEP group was higher than the other two groups. Pain score started over score 3 (all groups) and declined progressively through the 6th day, when it become “No pain”. Pleural effusion was seen in higher scores in control groups (40%)(p<0,001), than in IPPB group(10%), or IPPB+PEEP group(0%). Atelectasis were seen in higher scores in control groups (25%)(p<0,039), than in IPPB group(5%), or IPPB+PEEP group(0%).
We conclude that CABG decreases Pulmonary function in volume and gas exchange. This impairment recovers during the first days after the surgery.
The combined use of IPPB and PEEP improves pulmonary volume as well atelectasis and pleural effusion after Coronary Artery Bypass Surgery.
M.A. Vaz, None.