Impact of sleep disordered breathing on short-term post-operative outcome after elective coronary artery bypass graft surgery: a prospective observational study

Abstract

Sleep disordered breathing (SDB) is common in patients with coronary disease, but its impact on post-operative recovery after coronary artery bypass graft surgery (CABG) is unclear. We therefore determined the effects of SDB on post-operative outcome after elective CABG.In this prospective two-centre study, 219 patients due to receive elective CABG underwent cardiorespiratory polygraphy for SDB prior to surgery and were monitored for post-operative complications. The primary end-point was a composite of 30-day mortality or major post-operative complications (cardiac, respiratory, surgical, infectious, acute renal failure or stroke). Key secondary end-points were single components of the primary end-point.SDB was present in 69% and moderate/severe SDB in 43% of the CABG patients. There was no difference in the composite of 30-day mortality or major postoperative complications between patients with and without SDB (OR 0.97, 95% CI 0.49-1.96) and between patients with moderate/severe SDB and no/mild SDB (OR 1.07, 95% CI 0.55-2.06). However, moderate/severe SDB was associated with higher rates of mortality (crude OR 10.1, 95% CI 1.22-83.5), sepsis (OR 2.96, 95% CI 1.17-7.50) and respiratory complications (OR 2.85, 95% CI 1.46-5.55).Although SDB was not associated with higher overall morbidity/mortality, moderate/severe SDB may increase the risk of death, and septic and respiratory complications, after elective CABG.

Sleep apnoea and risk of post-operative infection: beyond cardiovascular impact

“…Another question of great clinical interest is whether treatment with continuous positive airway pressure (CPAP) in the subgroup of patients with excessive SDB prior to surgery (in this case CABG) would help protect them against post-operative infections, as posited by the authors of the present study (although they did not carry out such analysis) [5]. Although it is true that CPAP has been shown to decrease some systemic inflammatory markers [18] and could be an effective treatment in the perioperative period [19], its protective capacity is likely to be less than expected if the results of RUPPRECHT et al [5] are confirmed.…”

“…Although it is true that CPAP has been shown to decrease some systemic inflammatory markers [18] and could be an effective treatment in the perioperative period [19], its protective capacity is likely to be less than expected if the results of RUPPRECHT et al [5] are confirmed. This is because, on the one hand, the significant number of patients with central SA would theoretically limit the action of CPAP (an evaluation of the effect of adaptive servoventilation in this subgroup of patients would be an interesting research topic), while on the other hand, as has already been made evident by other studies, CPAP or noninvasive ventilation treatments in patients under sedation with a higher risk of infections (i.e.…”

“…All this means that studies such as the one reported by RUPPRECHT et al [5] cannot be considered definitive, although they do highlight the need to identify patients susceptible to obstructive sleep apnoea in the pre-operative period, as well as providing interesting working hypotheses that allow us to broaden our vision of the possible impact of sleep apnoea on clinically relevant outcomes beyond the cardiovascular sphere, even in patients with a high cardiovascular risk. There is an obvious need for sufficiently large-scale multicentre studies to assess the impact of sleep apnoea and CPAP treatment on a specific outcome of clinical interest, thereby avoiding the use of composites made up of variables with different origin, clinical relevance and management, which would probably not have an analogous relationship with sleep apnoea as they would activate very different pathophysiological routes.…”

“…In the current issue of the European Respiratory Journal, RUPPRECHT et al [5] publish the results of a study that examined a group of patients with high cardiovascular risk who had recently undergone elective coronary bypass graft surgery (CABG), to analyse the impact of pre-operative excessive SDB on parameters, such as the incidence of respiratory infections and complications, which are not exclusively cardiovascular but are extremely important in the immediate post-operative period. Although the study's main outcome (a broad composite of variables associated with post-operative mortality and a range of post-operative complications) showed no discrepancy between the group with excessive SDB and the group with a normal or near-normal SDB, this was not true of the incidence of sepsis and pneumonia, which were higher, particularly in the untreated forms of moderate to severe sleep apnoea.…”

Concomitant Sleep Apnea and Diabetes Mellitus Are Independently Associated with Cardiovascular Events and Hospitalization for Heart Failure after Coronary Artery Bypass Grafting

“…The sympathetic activation, blood pressure surges, and hypercoagulability caused by sleep apnea have been postulated as mediators of an increased cardiovascular risk [11]. Numerous studies have demonstrated the associations of sleep apnea with various short-and long-term complications after CABG, including new-onset atrial brillation, respiratory complications, hospital readmission, and major adverse cardiac and cerebrovascular events (MACCEs) [12][13][14][15]. These ndings were corroborated by the recently published results of the SABOT (Sleep Apnea and Bypass Operation) study, which revealed an association of sleep apnea with a 1.57-fold increase in the risk of developing MACCEs [16].…”