An audit of blood crossmatch ordering practices at the Aga Khan University Hospital: first step towards a maximum surgical blood ordering schedule (MSBOS).

OBJECTIVE In the absence of an explicit maximum blood order policy, ordering for blood transfusion is frequently based on subjective anticipation of blood loss instead of evidence based estimates of average requirement in a particular procedure. This study was done to assess current practice and the feasibility of a prospective randomized work to develop practice guidelines. METHOD We audited transfusion data for elective surgical procedures in our hospital during the last 2 years. Cross-matched to transfused ratio (C/T ratio) and Transfusion Index (Ti) for each of the elective surgical procedures was performed during the study period. C/T ratio is used as a measure of the efficiency of blood ordering practice. It should ideally be between 2 and 2.5. We compared our results with the ideal. RESULTS Data was analyzed for 32 elective surgical procedures in 2131 patients. Majority (2079) (97.56%) of the patients had C/T ratios higher than 2.5. Only 12 in 450 (21.11%) patients, had a Transfusion Index (Ti) higher than 0.5. There were 13 procedures in which both C/T ratio was greater than 2.5 and Ti less than or equal to 0.5. CONCLUSION In vast majority of elective surgical procedures routine cross match is not necessary. We propose a draft Maximum Surgical Blood Ordering Schedule (MSBOS). It provides guidelines for frequently performed elective surgical procedures by recommending the maximum number of units of blood to be cross-matched preoperatively. Implementation of MSBOS will result in about 60% reduction of cost to the patients.