Risk factors for postoperative delirium after spinal surgery: a systematic review and meta-analysis.

BACKGROUND: Postoperative delirium is common in older patients after spinal surgery. Many reports investigating the risk factors for delirium after spinal surgery have been published recently. METHODS: A literature search was performed using the Cochrane Library, Web of Science, PubMed, Embase, and Springer databases from inception to February 2019. Relevant studies involving patients with delirium who underwent spinal surgery were included if the studies contained data about blood transfusion or other related factors, such as haemoglobin, haematocrit, and blood loss levels. The Newcastle-Ottawa Scale was used for the study-quality evaluation. The pooled odds ratios or (standard) mean differences of the individual risk factors were estimated using the Mantel-Haenszel or inverse-variance methods. RESULTS: Fifteen observational studies met the inclusion criteria; the studies included a total of 583,290 patients (5431 patients with delirium and 577,859 patients without delirium). In addition to an advanced age, the results of the meta-analyses showed that living in an institution, diabetes, cerebral vascular diseases, pulmonary diseases, opioid use, length of surgery, intraoperative blood loss, blood transfusions, intraoperative infusion, preoperative albumin, postoperative albumin, preoperative haematocrit, postoperative haematocrit, preoperative haemoglobin, postoperative haemoglobin, preoperative sodium, postoperative sodium, Mini-Mental State Examination score, inability to ambulate, depression, number of medications, and treatment with multiple drugs (> three types) were significantly associated with delirium. CONCLUSION: The above-mentioned risk factors can be used to identify high-risk patients, and the appropriate prophylaxis strategies should be implemented to prevent delirium after spinal surgery.

Revaluation of clopidogrel: let the data speak for themselves.

Clopidogrel was believed to be superior to aspirin by the well-known CAPRIE trial. However, no other large clinical trials demonstrated the same results, but all focused on the combination use of clopidogrel with aspirin, and combination therapy in CREDO was called the "Emperor's New Clothes". However, no one overturned the results of these clinical trials by quantitatively analyzing them. We reviewed ten large-scale clinical trials about clopidogrel. On the basis of results of CAPRIE, CREDO and CHARISMA trials, we re-estimated their minimal sample sizes and their powers by three well-established statistical methodologies. From the results of CAPRIE, we inferred that the minimal sample size should be 85 086 or 84 968 but its power was only 30.70%. A huge gap existed. The same was also true of CREDO and CHARISMA trials. Moreover, in CAPRIE trial, 0 was included in the 95% confidence interval and 1 was included in the 95% confidence interval for the relative risk. There were some paradoxical data in CAPRIE trial. We are led to conclude that the results in CAPRIE, CREDO, and from the subgroup analysis in CHARISMA trials were questionable. These results failed to demonstrate that clopidogrel was superior to aspirin or that clopidogrel used in combination with aspirin was better than aspirin alone. The cost-effectiveness analyses by some previous studies were not reliable.

Restrictive versus liberal strategy for red blood-cell transfusion in hip fracture patients: A systematic review and meta-analysis.

BACKGROUND: Most clinical guidelines recommend a restrictive red-blood-cell (RBC) transfusion threshold. However, indications for transfusion in patients with a hip fracture have not been definitively evaluated or remain controversial. We compared the pros and cons of restrictive versus liberal transfusion strategies in patients undergoing hip fracture surgery. METHODS: Electronic databases were searched to identify randomized controlled trials (RCTs) and retrospective cohort studies (RCSs) to investigate the effects of a restrictive strategy versus its liberal counterpart in patients undergoing hip fracture surgery. The main clinical outcomes included delirium, mortality, infections, cardiogenic complications, thromboembolic events, cerebrovascular accidents, and length of hospital stay. The meta-analysis program of the Cochrane Collaboration (RevMan version 5.3.0) was used for data analysis. Statistical heterogeneity was assessed by both Cochran chi-squared test (Q test) and I test. Both Begg and Egger tests were used to assess potential publication bias. RESULTS: We identified 7 eligible RCTs and 2 eligible RCSs, involving 3,575 patients in total. In patients undergoing hip fracture surgery, we found no differences in frequency of delirium, mortality, the incidence rates of all infections, pneumonia, wound infection, all cardiovascular events, congestive heart failure, thromboembolic events or length of hospital stay between restrictive and liberal thresholds for RBC transfusion (P >.05). However, we found that the use of restrictive transfusion thresholds is associated with higher rates of acute coronary syndrome (P <.05) while liberal transfusion thresholds increase the risk of cerebrovascular accidents (P <.05). CONCLUSION: In patients undergoing hip fracture surgery, clinicians should evaluate the patient's condition in detail and adopt different transfusion strategies according to the patient's specific situation rather than merely using a certain transfusion strategy.