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October 1999


Ileana Lopez-Plaza, M.D., Associate Medical Director, Transfusion Services


Increasingly, admissions for elective surgical procedures are occurring the same day of surgery. Most preoperative laboratory testing is completed days in advance of the scheduled procedure. This often does not include blood bank testing, creating a logistic challenge for the transfusion service when patients are admitted when patients are admitted.

Typically, patients must present to the preop holding areas a few hours before a scheduled procedure. For surgical cases requiring the use of blood, a sample is drawn at this time for compatibility testing. Often this provides less than two hours of turn-around-time to complete testing before a scheduled surgery. Any delay in blood availability can impact the patient and operating room schedule significantly.


Samples for compatibility testing can be collected up to 14 days prior to a scheduled procedure. Typing, screening, and crossmatching must be performed by the blood bank servicing the facility where the procedure is to be done. Blood needed for surgery can be crossmatched the night before surgery, preventing delays in blood availability the day of the procedure. Further, it allows time to evaluate a positive antibody screen and obtain compatible blood for these patients. Samples drawn at preadmission are tracked to the patient the day of the surgery by comparing a unique numeric identifier present on both the band that the patient was provided with at the time the sample was drawn, as well as on the blood sample itself. This identification band provides the only link between the patient and the sample.

In order to perform preadmission testing, patients need to meet the following criteria: a) the patient has not been transfused or pregnant in the past three months; b) the band provided to the patient at time of the sample was drawn is present on the patient, the day of surgery. Patients, who do not meet these criteria, must have their sample drawn within three days before surgery. Samples drawn the day of surgery, must be collected a minimum of two hours beforehand in order to complete testing once the sample has reached the blood bank. Patients with positive antibody screens will require additional time for antibody identification and blood availability. Depending on antibody specificity, it may take hours or more for blood availability. Patients drawn in advance, who do not have the band on them the day of the surgery will need to be redrawn, and all testing repeated prior to the release of crossmatched blood.



Preoperative services that the blood bank provides include preoperative autologous blood donations and the Maximum Surgical Blood Ordering Schedule (MSBOS).



MSBOS is based on data collected from surgical records of blood usage at an institution. The MSBOS provides recommendations on the maximum number of units to order for common elective procedures. Options for testing include no blood required, type and screen required, or type and crossmatches, stating the number of units to be crossmatched. It is recommended that surgeons, who routinely require less than one unit of blood, should only order a type and screen. Once the MSBOS is established, the transfusion service will follow these guidelines to meet blood requirements for each patient undergoing that particular procedure.

MSBOS facilitates the availability of blood for surgery by minimizing the amount of blood tied up in the crossmatch inventory. Also, it prevents patients from going to the OR without sufficient blood ordered.



Autologous blood collection should be attempted for every medically eligible patient undergoing an elective surgical procedure who will require transfusion. Contraindications for autologous donations generally include cardiovascular disease with compromised hemodynamic reserves or risk of bacterial contamination of the collected blood.

Unnecessary collection of autologous blood is not without risks to the donor. The decrease in hemoglobin levels put the patient at risk for transfusion. Units are typically collected on a weekly basis and no less than 72 hours prior to surgery.

Blood ABO and Rh typing are the only required tests for an autologous unit collected and transfused in the same facility. However, autologous units that are collected by a blood center need to be fully tested (including viral markers) in order to be distributed to the hospital facilities. Autologous blood donation is best ordered as packed red cells versus whole blood, in order to extend the shelf life of that unit up to six weeks after collection.



Most transfusion services provide options that facilitate blood availability for surgery. Physicians (surgeons, primary care), medical institutions, and health insurance companies should maximize the use of these benefits provided by transfusion services.

Copyright 1999, Institute For Transfusion Medicine

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