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This systematic review and meta-analysis appraises the utility of point-of-care platelet function tests for predicting blood loss and transfusion requirements in cardiac surgical patients, and analyses whether their use within a transfusion management algorithm is associated with improved patient outcomes. We included 30 observational studies incorporating 3044 patients in the qualitative assessment, and nine randomised controlled trials including 1057 patients in the meta-analysis. Platelet function tests demonstrated significant variability in their ability to predict blood loss and transfusion requirements. Their use within a blood transfusion algorithm demonstrated a reduction in blood loss at longest follow-up (mean difference −102.9 ml (95% CI −149.9 to −56.1 ml), p < 0.001), and transfusion of packed red cells ( RR 0.86 (95% CI 0.78−0.94), p = 0.001) and fresh frozen plasma ( RR 0.42 (95% CI 0.30−0.59), p < 0.001). Viscoelastic methods used in combination with other platelet function tests achieved greater reduction in blood loss (mean difference −111.8 ml (95% CI −174.9 to −49.1 ml), p = 0.0005) compared with their use alone (mean difference −90.6 ml (95% CI 166.1−15.0 ml), p = 0.02). We conclude that incorporation of point-of-care platelet function tests into transfusion management algorithms is associated with a reduction in blood loss and transfusion requirements in cardiac surgery patients. [ABSTRACT FROM AUTHOR]

Because of a lack of contemporary data regarding seizures after cardiac surgery, we undertook a retrospective analysis of prospectively collected data from 11 529 patients in whom cardiopulmonary bypass was used from January 2004 to December 2010. A convulsive seizure was defined as a transient episode of disturbed brain function characterised by abnormal involuntary motor movements. Multivariate regression analysis was performed to identify independent predictors of postoperative seizures. A total of 100 (0.9%) patients developed postoperative convulsive seizures. Generalised and focal seizures were identified in 68 and 32 patients, respectively. The median (IQR [range]) time after surgery when the seizure occurred was 7 (6-12 [1-216]) h and 8 (6-11 [4-18]) h, respectively. Epileptiform findings on electroencephalography were seen in 19 patients. Independent predictors of postoperative seizures included age, female sex, redo cardiac surgery, calcification of ascending aorta, congestive heart failure, deep hypothermic circulatory arrest, duration of aortic cross-clamp and tranexamic acid. When tested in a multivariate regression analysis, tranexamic acid was a strong independent predictor of seizures ( OR 14.3, 95% CI 5.5-36.7; p < 0.001). Patients with convulsive seizures had 2.5 times higher in-hospital mortality rates and twice the length of hospital stay compared with patients without convulsive seizures. Mean ( IQR [range]) length of stay in the intensive care unit was 115 (49-228 [32-481]) h in patients with convulsive seizures compared with 26 (22-69 [14-1080]) h in patients without seizures (p < 0.001). Convulsive seizures are a serious postoperative complication after cardiac surgery. As tranexamic acid is the only modifiable factor, its administration, particularly in doses exceeding 80 mg.kg−1, should be weighed against the risk of postoperative seizures. [ABSTRACT FROM AUTHOR]

Background The time to recovery from vapour anaesthesia is shortened by an increase in ventilation while maintaining normocapnia. Hypercapnia during emergence from anaesthesia in spontaneously breathing patients also increases anaesthetic clearance from the brain by increasing cerebral blood flow. We hypothesised that hypercapnia-induced hyperpnoea accelerates emergence from sevoflurane anaesthesia compared to the standard anaesthesia protocol. Methods After Ethics Review Board approval, 44 ASA I- III patients undergoing elective gynaecological surgery were randomised after surgery to either hypercapnic hyperpnoea or control groups. In the hypercapnic hyperpnoea group, the end-tidal CO2 was adjusted to a range of 6.0-7.3 kPa to maintain a minute ventilation of 10-15 l/min. Recovery indices were compared using unpaired t-tests and ANOVA. Results Prior to extubation, minute ventilation and end-tidal CO2 in hypercapnic hyperpnoea and control groups were 10.3 ± 1.7 l/min vs. 5.4 ± 1.2 l/min ( P < 0.001) and 6.6 ± 0.6 kPa and 5.2 ± 0.5 kPa ( P < 0.001), respectively. Compared to control, the study group had shorter time to extubation [4.4 ± 1.3 ( SD) vs. 9.8 ± 4.4 min, P < 0.01], BIS recovery to > 75 (2.4 ± 0.9 vs. 6.1 ± 3.1 min, P < 0.01), eye opening (3.9 ± 1.6 vs. 9.8 ± 6.2 min, P < 0.01), eligibility for leaving operating room (5.1 ± 1.2 vs. 11.1 ± 4.6 min, P < 0.01), and post-anaesthesia care unit (73.9 ± 14.2 vs. 89.4 ± 22.6) Conclusion Hypercapnic hyperpnoea in spontaneously breathing patients halves the time of recovery from sevoflurane-induced anaesthesia in the operating room. [ABSTRACT FROM AUTHOR]

Background: There is a concern that obesity may play a role in prolonging emergence from fat-soluble inhalational anaesthetics. We hypothesized that increased pulmonary clearance of isoflurane will shorten immediate recovery from anaesthesia and post-anaesthesia care unit (PACU) stay in obese patients. Methods: After Ethics Review Board approval, 44 ASA I-III patients with BMI>30 kg/m2 undergoing elective gynaecological or urological surgery were randomized after completion of surgery to either an isocapnic hyperpnoea (IH) or a conventional recovery (C) group. The anaesthesia protocol included propofol, fentanyl, morphine, rocuronium and isoflurane in air/O2. Groups were compared using unpaired t-test and ANOVA. Results: Minute ventilation in the IH group before extubation was 22.6±2.7 vs. 6.3±1.8 l/min in the C group. Compared with C, the IH group had a shorter time to extubation (5.4±2.7 vs. 15.8±2.7 min, P<0.01), initiation of spontaneous ventilation (2.7±2.3 vs. 6.5±4.5 min, P<0.01), BIS recovery >75 (3.2±2.3 vs. 8.9±5.8 min, P<0.01), eye opening (4.6±2.9 vs. 13.6±7.1 min, P<0.01) and eligibility for leaving the operating room (7.1±2.9 vs. 19.9±11.9 min, P<0.01). There was no difference in time for eligibility for PACU discharge. Conclusion: Increasing alveolar ventilation enhances anaesthetic elimination and accelerates short-term recovery in obese patients. [ABSTRACT FROM AUTHOR]