Different CABG methods in patients with chronic obstructive pulmonary disease. Postoperative pulmonary function in coronary artery bypass graft surgery patients undergoing early tracheal extubation: a comparison between short-term mechanical ventilation and early extubation. Effects of N-acetylcysteine on pulmonary function in patients undergoing coronary artery bypass surgery with cardiopulmonary bypass. Morbidity associated with systemic corticosteroid preparation for coronary artery bypass grafting in patients with chronic obstructive pulmonary disease: a case control study. The effectiveness of incentive spirometry with physical therapy for high-risk patients after coronary artery bypass surgery.
Pulmonary dysfunction is still a major problem in coronary artery bypass grafting (CABG). The purpose of this randomized study was to determine the effect of different CABG techniques on pulmonary function.
                Fifty eight patients with severe obstructive pulmonary disease had elective isolated coronary surgery. The surgical methods for the patients with chronic obstructive pulmonary disease (COPD) were standard CABG in 18 patients (group 1), beating heart surgery in 19 patients (group 2), and minimally invasive direct coronary artery bypass grafting (MIDCABG) in 21 patients (group 3).
                The earliest extubation time was from group 3 (p < 0.001). The average stay in the intensive care unit was significantly longer in group 1 (2.6 +/- 1.5 days) than in groups 2 (1.4 +/- 0.8 days) and 3 (1.1 +/- 0.8 days) (p < 0.05). The most prevalent respiratory morbidity was atelectasis that developed in 6 patients from group 1, in 2 patients from group 2, and in 3 patients from group 3. Forced expiratory volumes in 1 second (FEV1) obtained in the second postoperative month were significantly lower than preoperative values only in group 1 (p < 0.05). Forced vital capacity (FVC) values were significantly lower than the preoperative values in all three groups (p < 0.05).
                Off-pump bypass surgical procedures are more advantageous than on-pump methods for patients with COPD. These patients can be operated on using the beating heart technique or by using MIDCABG to prevent side effects of CPB on pulmonary function and effects of sternotomy. To evaluate the effect of a short period of mechanical ventilation (3 hours) versus immediate extubation (within 1 hour of surgery) on pulmonary function, gas exchange, and pulmonary complications after coronary artery bypass graft (CABG) surgery.
                Prospective randomized study.
                University teaching hospital.
                Thirty-five patients undergoing CABG surgery.
                Patients were randomized into 2 groups. Patients in group I were extubated as soon as possible after surgery. Patients in group II were ventilated for a minimum of 3 hours after surgery. Patients in both groups were extubated only after achieving predetermined extubation criteria. Patients who did not meet the criteria for extubation within the predetermined set time limit (90 minutes in group I and 6 hours in group II) were withdrawn from the study. Pulmonary function tests (vital capacity, forced expiratory volume in 1 second, total lung capacity, functional residual capacity), arterial blood gases, and chest radiographs were done preoperatively and postoperatively. Pulmonary complications were recorded.
                Demographic data were similar between groups. The mean time to extubation in group I was 45.7 plus minus 27.6 minutes and in group II was 201.4 plus minus 21 minutes (p < 0.01). Two patients in group I and 1 patient in group II did not meet the extubation criteria within the predetermined set time limit and were excluded from the study. In both groups, there was a significant decline in pulmonary function but no differences between groups at 24 or 72 hours after surgery. There were no differences between groups in blood gases, atelectasis scores, or pulmonary complications.
                The data suggest that extending mechanical ventilation after CABG surgery does not affect pulmonary function. Provided that routine extubation criteria are met, patients can be safely extubated early (within 1 hour) after major cardiac surgery without concerns of further pulmonary derangement.
                Copyright 2002, Elsevier Science (USA). All rights reserved. Cardiopulmonary bypass (CPB) has been implicated in causing poor pulmonary gas exchange postoperatively in patients undergoing coronary artery bypass grafting (CABG) procedures. In this prospective, randomized, double-blind, placebo-controlled study, we examined the pulmonary effects of N-acetylcysteine (NAC) in patients undergoing CABG. Twenty patients undergoing elective CABG and early tracheal extubation were randomized into two groups. Group I (ten patients) received a physiologic salt solution as a placebo in a continuous intravenous infusion for one hour before CPB and 24 hours after CPB; Group II (ten patients) received 100 mg/ kg NAC intravenously for one hour before CPB and 40 mg/kg/day at 24 hours after CPB. Perioperative hemodynamic and pulmonary data were recorded. Postoperative tracheal extubation was accomplished at the earliest appropriate time. The postoperative clinical course was similar in the two groups. Both groups exhibited significant postoperative increases in A-a oxygen gradient (p < 0.01), but patients in Group II exhibited significantly lower increases in postoperative A-a oxygen gradient (p < 0.006). Other hemodynamic and pulmonary data (pulmonary capillary wedge pressure, pulmonary vascular resistance (PVR), cardiac index (CI), shunt flow, dynamic lung compliance and static lung compliance) exhibited no differences between the groups. There was no significant difference in terms of intubation time. The malondialdehyde (MDA) increase in Group II following CPB was found to be significantly lower than in Group I (p = 0.043). This clinical study reveals that administration of NAC to patients undergoing elective CABG with CPB improves systemic oxygenation. There was no effect in other pulmonary parameters and in terms of intubation time. Coronary artery bypass grafting (CABG) is associated with high morbidity in patients with chronic obstructive pulmonary disease (COPD).We examine the effect of preoperative systemic corticosteroids on morbidity in this setting.
                Ninety candidates for elective CABG participated in a prospective, open randomized trial, including 30 patients with COPD who received a single injection of a long-acting corticosteroid, 30 with COPD who received placebo, and 30 without COPD who served as controls. Primary end-points were postoperative pulmonary and nonpulmonary complications. Secondary end-points were length of hospital stay (LOS), ICU stay of less than 24 hours and more than 48 hours, duration of mechanical ventilation, and time to walking and sitting.
                The rate of pulmonary complications was similar in the two COPD groups and in the COPD patients and controls. The placebo group had more major nonpulmonary complications than the treatment group, but the difference was not statistically significant (26% vs. 17%, P = NS). The non-COPD control group had significantly fewer nonpulmonary complications than the COPD patients (treatment+placebo) (33% vs 70%, P = 0.014) and a similar rate of pulmonary complications. There was a statistically significant difference between the treated and placebo COPD groups in ICU stay less than 24 hours (P < or = 0.001) and more than 48 hours (P = 0.03) and hospital stay (P = 0.013). On stepwise analysis, only age and number of coronary grafts were predictors of pulmonary complications.
                The use of preoperative systemic corticosteroids in patients with COPD undergoing CABG may shorten ICU and hospital stay. The purpose of this study was to determine whether the addition of incentive spirometry (IS) to postoperative pulmonary physical therapy is more effective than physical therapy alone in reducing postoperative pulmonary complications in high-risk patients after coronary artery bypass grafting (CABG). Patients were given the spirometer and instructed in its use, as often occurs in clinical settings.
                Patients with chronic airflow limitation following CABG (N = 185) participated.
                Subjects were randomly assigned to receive either postoperative pulmonary physical therapy (breathing exercises, secretion removal, mobility) or physical therapy combined with IS.
                No difference was found between the two groups in atelectasis, spirometry, oxygen saturation, pulmonary infection, or hospital stay.
                Incentive spirometry combined with physical therapy is no more effective than postoperative physical therapy alone in reducing atelectasis for this population. Use of the spirometer, however, was not monitored, and although the study mimicked practice as it often occurs, the effectiveness of the spirometer cannot be fully evaluated.
Our update review suggests there is no evidence of benefit from IS in reducing pulmonary complications and in decreasing the negative effects on pulmonary function in patients undergoing CABG. In view of the modest number of patients studied, methodological shortcomings and poor reporting of the included trials, these results should still be interpreted cautiously. An appropriately powered trial of high methodological rigour is needed to determine if there are patients who may derive benefit from IS following CABG.