Analyse risk-profile, outcome, costs and identify predictors of ICU readmission after elective coronary artery bypass grafting.
Prospectively entered data of 3120 consecutive CABG patients was analysed using Chi-square, t-test and multivariate logistic regression analysis. Group-A (n-118, readmission to ICU), Group-B (n-3002, routine single ICU admission). Respiratory failure, haemodynamic instability, acute renal failure and re-exploration were the main reasons for readmission.
Preoperatively, Parsonnet (16 vs 7, p-0.0001), Euroscore (6 vs 3, p-0.0001), age (70 vs 64, p-0.0001), BMI (27 vs 28, p-0.03), COAD (21% vs 18%, p-0.001), PVD (21% vs 10%, p-0.001), renal dysfunction (6% vs 2%, p-0.003), unstable-angina (39% vs 8%, p-0.0001), CCF (38% vs 19%, p-0.0001), poor LV function (17% vs 4%, p-0.0001), inotropic support (4% vs 1%, p-0.001) cardiopulmonary bypass (74min vs 62min, p-0.0001) and ischemia (44min vs 34min, p-0.0001) times were higher in group-A. The gender-ratio, smoking, diabetes, hypertension, CVA, MI and coronary disease severity were comparable. Postoperatively, inotrope + IABP (73% vs 12%, p-0.0001), arrhythmia (73% vs 28%, p-0.0001), MI (12% vs 1%, p-0.0001), re-exploration (26% vs 3%, p-0.0001), blood loss (830mls vs 641mls, p-0.001), transfusion (799mls vs 235mls, p-0.0001), CVA (8% vs 1%, p-0.0001), renal dysfunction (42% vs 4%, p-0.0001), wound infection (12% vs 5%, p-0.002), sternal dehiscence (14% vs 1%, 0.0001), multisystem failure (11% vs 0, p-0.0001) and mortality (32% vs 1%, p-0.0001) were higher in group-A.Longer ICU (183hrs vs 30hrs, p-0.0001), HDU (9days vs 2days, p-0.0001) and ward stay (9days vs 5 days, p-0.0001) meant that the cost of care per patient in group-A was four times greater than group-B (£18,380 vs £4,335).
Despite a four-fold increase in cost, the mortality rate of patients readmitted to ICU is 23 times higher than routine patients. Ischaemia time > 80 min, Parsonnet > 10, Euroscore > 9, sternal dehiscence, ventricular arrhythmias and postoperative renal dysfunction are predictors of readmission.
Longer HDU care for high-risk patients based on predictors could be a cost-effective way to reduce mortality and readmission rate. Table - I.
Predictors of ICU readmission in our analysis.Predictorsp-valueOdds ratio95% confidence intervalX-clamp time > 80 min0.00014.12 –8.4Parsonnet score > 100.00014.72.4 –9.2Euroscore > 90.000129.610 –87.2Sternal dehiscence0.00019.72.8 –32.9VF / VT0.000139.813.6 –116.4Postoperative renal failure0.000118.65 –69.5
J. Alex, None.