Cambridge-Miami Score for Intestinal Transplantation Preoperative Risk Assessment: Initial Development and Validation

Abstract

Introduction Preoperative quantification of survival after transplantation would assist in assessing patients. We have developed a preliminary preoperative scoring system, called the Cambridge-Miami (CaMi) score, for transplantation of the small intestine either alone or as a composite graft. Methods The score combines putative risk factors for early-, medium-, and long-term survival. Factors included were loss of venous access and impairment of organs or systems not corrected by transplantation. Each factor was scored 0–3. A score of 3 indicated comorbidity approaching a contraindication for transplantation, that which might lead to but was not currently an adverse risk factor scored 1, and that presenting a definite but moderate increase in risk scored 2. The preoperative scores of 20 patients who had received intestinal transplants either isolated or as part of a cluster graft, who had either been followed up postoperatively for at least 10 years, or died within 10 years were compared with their survivals. Results Postoperative survival and CaMi score inversely correlated when analysed using Spearman test (r s = −0.82; P = .0001). A score of <3 associated with survival ≥3 years (12/12 patients) and >3 with survival of <6 months (4/4). Patient Kaplan-Meier (KM) survival curves for patients grouped according to CaMi score became significantly different from group 0 to group 3. Using this as a threshold score patients grouped as either >2 or <3 had significantly different survival rates (log-rank; P = .0001), KM median survival hazard ratio (HR) = 6, and rate of death KM HR = 5. Receiver-operator characteristics indicate a high degree of accuracy for prediction of death with an area under the curve (C statistic) at 3 years of 0.98, at 5 years of 0.82, and at 10 years of 0.65. Conclusion This initial validation suggested that the preoperative CaMi score predicted postoperative survival.