PURPOSE: To determine the efficacy of bilevel positive airway pressure (BiPAP) in prevention of postoperative atelectasis in patients with off-pump coronary artery bypass grafting (OPCAB) with low left ventricular ejection fraction(EF) £35% and effect on various haemodynamic & oxygenation parameter.
METHODS: Forty patients, who underwent elective OPCAB were randomly assigned into two groups i.e group-B (BiPAP) and group-C (Control). All patients received same regimen of medications. Group-B was kept on BiPAP immediately following extubation while group-C received conventional physiotherapy only. All haemodynamic and oxygenation parameters were recorded and chest radiographs were done to find out incidence of atelactasis. Patients were followed up to their discharge.
RESULTS: In group-B cardiac output was reduced after application of BiPAP at 0 hrs & 12 hrs but later on it normalized. There was no other significant effect of BiPAP on haemodynamic parameters.As far as the oxygenation is concerned PaO2 remained high throughout first 48 hrs and the difference was significant at 12 hrs (PaO2 mmHg; group B–146±37, group-C–121±18) (p<0.05) and at 48 hrs (PaO2 mmHg; group-B–146±41, group-C –110±9) (p<0.05).There was highly significant difference in the occurrence of atelectasis in group-B and group-C (10% v/s 60%) (p<0.003). Although the effects on ICU stay, hospital stay and mortality was same.
CONCLUSION: In patients undergoing elective cardiac surgery with low EF, intensive use of BiPAP can be considered as effective means of reducing the deleterious consequences of cardiac surgery on postoperative pulmonary complications originating form atelectasis.
CLINICAL IMPLICATIONS: BiPAP may be considered for poor LVEF <35% post cardiac surgery patients to prevent atelectasis & it's attendent complications.
DISCLOSURE: Yatin Mehta, No Financial Disclosure Information; No Product/Research Disclosure Information