Objective: Cardiopulmonary bypass (CPB) is associated with thyroid hormone changes consistent with euthyroid sick syndrome. Similar changes have been observed after general surgical operations. Thyroid hormone changes and their association with global oxygen consumption were studied in tow-risk patients undergoing coronary artery bypass grafting (CABG) With and without CPB. Methods: Fifty-two patients undergoing primary CABG by the same surgeon were randomised into either on-pump (ONCAB, n = 26) or off-pump (OPCAB, n = 26) groups. Thyroid-stimulating hormone (TSH), free thyroxine (fT4) and free triiodothyronine (fT3) levels were measured at sequential time-points using chemiluminescence assays. Global oxygen consumption was measured at sequential time-points using a continuous cardiac output Swan-Ganz catheter. Results: In both groups TSH and fT4 remained within normal range throughout the study. There was a similar and progressive decline in fT3 levels with no significant difference between the groups over time (p = 0.42). Mean fT3 levels at 24 h were below the normal range and significantly lower than baseline values (ONCAB, 3.3 +/- 0.69 pmol/L vs 5.1 +/- 0.41 pmol/L, p < 0.001; OPCAB, 3.3 +/- 0.51 pmol/L vs 5.0 +/- 0.46 pmol/L, p < 0.001). There was a significant inverse relationship between fT3 levels and global oxygen consumption. Conclusions: Off-pump surgery is associated With thyroid hormone changes similar to conventional surgical revascularisation. The data suggest that further studies into T3 administration during OPCAB may be warranted. (C) 2009 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Objective: Cardiopulmonary bypass (CPB) is associated with gut mucosal hypoxia, which may contribute to gastrointestinal complications. We examined gastric mucosal oxygenation together with whole-body oxygen flux in low-risk patients undergoing coronary artery bypass grafting (CABG) with and without CPB. Methods: Fifty-four patients undergoing primary CABG by the same surgeon were randomized into either on-pump (ONCAB, n = 27) or off-pump (OPCAB, n = 27) groups. The ONCAB group underwent mild hypothermic (35degreesC) pulsatile CPB with arterial line filtration. Each patient underwent perioperative monitoring with continuous tonometry and cardiac output devices. Gastric intramucosal pH (pHi), gastric-arterial carbon dioxide partial pressure difference (CO2 gap), whole-body oxygen delivery (DO,) and consumption (VO2) and whole-body oxygen extraction fraction were measured at sequential time-points intraoperatively and up to 6 h postoperatively. Anaesthetic management was standardized. Results: Both groups had similar demographic makeup and extent of revascularization (ONCAB 2.6 +/- 0.9 grafts versus OPCAB 2.5 +/- 0.8 grafts; P = 0.55). The ONCAB group had a mean (+/-SD) CPB time of 62 +/- 25 min and aortic cross-clamp time of 32 +/- 11 min. In both groups there was a similar and progressive drop in pHi intraoperatively. Postoperatively, there was a gradual separation between the groups with ONCAB patients showing no further decline in pHi, while further deterioration was observed in the OPCAB group up to 6 h postoperatively. There was a significant difference between the groups over time (P = 0.03). There was a corresponding progressive rise in CO2 gap perioperatively in both groups, with ONCAB patients demonstrating superior preservation of gastric mucosal oxygenation in the early postoperative period. Global oxygen utilization measurements showed superior DO2 and VO2 in the OPCAB group throughout the study. Conclusions: Despite superior global oxygen flux associated with beating-heart revascularization, gastric mucosal hypoxia occurred to similar extents in both groups with worsening trends for the OPCAB patients postoperatively. The splanchnic pathophysiology during beating-heart revascularization should be further explored. (C) 2003 Elsevier Science B.V. All rights reserved.

We describe the use of right pleurotomy combined with right pericardial release during off-pump coronary surgery. The maneuver releases the compression exerted on the right cardiac chambers during cardiac verticalization and improves hemodynamic stability during exposure of the posterior or lateral coronary vessels.

Summary Cardiopulmonary bypass has several associated deleterious effects that include a systemic inflammatory response, coagulopathy, central nervous system complications and a variable degree of end‐organ damage. The recent upsurge in interest in ‘beating‐heart’ surgery attempts to avoid these deleterious effects. Advances in surgical technique, such as the use of intracoronary shunts and the Octopus retractor, have made beating‐heart surgery a reality. The challenges for the anaesthetist are greater than for coronary artery surgery using cardiopulmonary bypass, and whilst some advantages are proven, such as the lack of the inflammatory response and the decreased need for blood or blood products, others have yet to be proved and there is a need for further research. The advantages and disadvantages need to be evaluated in randomised studies in order to confirm the safety and efficacy of these new techniques in terms of long‐term graft patency and decreased morbidity.