| Background and Objectives: With an increase in the aging population worldwide, the demand for cardiac operations has grown substantially. Fast track perioperative care was initiated over 40 years ago for cost containment and more efficient use of healthcare resources. The intent is to wean cardiac surgical patients from the ventilator within 6-8 hours after surgery and to promote faster recovery to shorten the length of stay (LOS) in the intensive care unit (ICU) and in the hospital, thus reducing healthcare costs. In order to promote the fast-track practice in cardiac surgical patient, we conducted three studies to: 1) update the evidence on the safety and effectiveness of fast-track management for adult cardiac patients compared to conventional extubation on the following day; 2) externally validate and recalibrate a fast-track failure model in emergency and elective cardiac patients; 3) compare the effectiveness of different weaning protocol (adaptive support ventilation (ASV) based) versus physician-led weaning and extubation strategy in patients undergoing elective valvular surgery.;Methods: In the first study, we conducted a systematic review to include all randomised controlled trials (RCTs) comparing fast-track care (low dose opioids or fast-track protocols) with conventional care (high dose of opioids or with no fast-track protocols) for adult patients undergoing cardiac surgery. The outcomes were mortality (both short-term and long-term), morbidities (myocardial infarction, reintubation, acute renal failure, major sepsis, wound infection, major bleeding and stroke), time to extubation, and LOS in ICU and hospital, quality of life and healthcare cost. The relative risk (RR) for nominal outcome and weighed mean difference (WMD) for continuous outcome, and associated 95% confidence intervals (95% CI) were reported for the meta-analyses.;In the second study, we externally validated and updated the original model of St-Mary's Hospital Fast-Track Failure risk model on our patients included in the Prince of Wales Hospital cardiac database. Similar exclusion criteria were used. The model was updated in a stepwise manner until a satisfactory model performance was obtained. The calibration and discrimination of the model was tested by Hosmer-Lemeshow goodness-of-fit test (H-L test) and the area under receiver operating curve (AUROC), respectively.;Finally, a prospective randomised controlled trial was conducted. After ethics committee approval, 68 consecutive patients undergoing elective valve (with or without coronary artery bypass graft) surgery were recruited and randomly assigned to receive either ASV-based or physician-led weaning protocols in ICU. The primary outcome was the duration of mechanical ventilation. The secondary outcomes included time to extubation, the number of manual settings, number of alarms, LOS in ICU and hospital. The parameters were compared between groups using appropriate Mann-Whitney U, Chi-square or Fisher's exact tests.;Results: Twenty-five RCTs involving 4,118 patients were included in a systematic review. The risk of mortality at any time was similar between the low-dose versus high-dose opioid based general anaesthesia and the use versus no use of the time-directed extubation protocols . Compared to high-dose opioid based anaesthesia, the low-dose opioid based general anaesthesia showed similar risks of postoperative complications, including myocardial infarction , reintubation, acute renal failure , major bleeding and stroke . There were no difference in the risk of myocardial infarction, reintubation , acute renal failure, major bleeding and stroke when comparing the time-directed fast track protocol to routine protocol. There was low heterogeneity between studies for the mortality and morbidity outcomes. The low-dose opioid based general anaesthesia was associated with shorter time to extubation and ICU stay, but not the hospital length of stay. Similar effects were observed in comparing the time-directed extubation to routine protocol where the time to extubation and ICU stay were significantly shorter in early extubation group. Time-directed protocol was not associated with a reduction in hospital length of stay even though there was a high level of heterogeneity between trials.;In the second study, 175 of 1,597 (11%) failed fast-track management. The main reasons for fast-track failure included 48 (3%) deaths within 30 days after surgery, 53 (3%) readmissions to ICU and 107 (7%) ICU stays of more than 48 hours. The external validation and recalibration of the St-Mary's fast-track failure risk model on 1,575 patients had good discrimination (C statistics = 0.79, 95% CI: 0.75 to 0.83) and calibration (P = 0.40).;In the final study, 53 patients completed the study and were analysed. The ASV-based weaning protocol significantly reduced the duration of mechanical ventilation and time to extubation, requiring less manual setting of ventilator but more arterial blood gases, when compared with physician-led weaning/extubation in patients undergoing valve surgery. There were no differences in the LOS in ICU and postoperative stay in hospital, nor the risk of mortality in ICU and risk of readmission to ICU between two groups. (Abstract shortened by UMI.). |
