A best evidence topic was written according to a structured protocol. The question addressed was: in patients undergoing oesophagectomy for oesophageal malignancy, is low serum albumin associated with postoperative complications? Altogether, 87 papers were found using the reported search, of which 16 demonstrated the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. This paper includes 2 level 2 papers, 12 level 3 papers and 2 level 4 papers. All the papers compared either all or some of the following postoperative complications: mortality, morbidity, anastomotic leak, respiratory and non-respiratory complications, and length of hospital stay. Eleven of the 16 papers found an association between low serum albumin and postoperative complications. Of these, one study showed that low serum albumin combined with low fibrinogen levels (FA score) was predictive of postoperative recurrence of oesophageal cancer. Another study showed that when combined with white cell count and C-reactive protein (CRP, NUn score), serum albumin had a high diagnostic accuracy for major complications after postoperative day 3. The largest study compared the in-hospital mortality in 7227 patients who underwent oesophageal surgery for malignancy. The percentage of in-hospital mortality was associated with low serum albumin (<15.0 vs >35.0 g/l, 21.0 vs 11.3%, P <0.001). Five of the 16 papers found no significant association between low serum albumin and postoperative complications. Of these papers, one showed that low serum albumin was not an independent risk factor, while four others found no association between low serum albumin with respiratory complications, anastomotic leak and postoperative mortality. Instead, these studies found other factors responsible for postoperative complications such as: CRP, smoking, disease duration, malnutrition and low T-cell levels. Taken together, while low serum albumin is associated with postoperative complications, opinion regarding the prognostic value of low serum albumin and nutritional support remains conflicted. Because of the confounding factors encountered in these studies, the clinician should consider the finding of low serum albumin in patients, together with disease and surgical factors to provide optimal care for these patients.

This best evidence topic on cardiothoracic surgery was written using a structured protocol. The question addressed was: 'in an adult patient requiring cardiac surgery, can a thyroidectomy for a large retrosternal goitre be performed with good outcomes as a combined procedure?' Of 150 papers identified through the literature search, 16 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, study type, patient group studied, relevant outcomes and results were tabulated. This paper includes 3 Level 4 papers and 13 case reports. All papers reported postoperative outcomes and five papers reported intraoperative outcomes. Of a total cohort of 32 patients, 25 were euthyroid prior to combined surgery. Twenty-nine of 32 thyroid surgeries were performed immediately prior to cardiac surgery in the combined procedure sequence. Post-procedural complications including transient recurrent laryngeal palsy and tracheomalacia were reported in 8 patients. There was one intraoperative death. Where reported, all patients were euthyroid on follow-up. All identified papers reported good outcomes with combined thyroidectomy and cardiac surgery.