دانلود کتاب پزشکی انتقال خون – مطالعات موردی و مدیریت بالینی

A 19-year-old woman, 10 weeks pregnant, presented to her local hospital with heavy vaginal bleeding. Spontaneous incomplete miscarriage was diagnosed. She continued bleeding for the next 24 h. Her hemoglobin decreased from 115 to 79 g/L. Two units of red cells were ordered. Thirty minutes into the transfusion of the first unit, started around 10 p.m., the patient reported “tightness of the chest” to the nurse, who allowed the transfusion to continue. The symptoms worsened, and the transfusion was stopped, with nearly the whole unit transfused into patient. Later that night, evacuation of retained products of conception (ERPC) was performed under general anesthesia. The second red cell unit was transfused in the theater. The next day, hemoglobin was 94 gL, and the patient was discharged home on ferrous sulfate. Twenty-four hours later, the hospital phoned the patient to say that she had been inadvertently given two units of red cells of the wrong blood group; the patient was A, RhD negative; the two transfused units were B, RhD positive. The error originated in the hospital blood bank and was caused by the transposition of the compatibility label (“tag”) onto the blood units destined for another patient. The patient was referred to a tertiary center for further management. Q1. How did this error happen? A1: Pretransfusion tests (PTT) traditionally included cross-matching of patient’s plasma and a sample from the unit selected for transfusion by indirect antiglobulin test (IAT) at 37 °C. More recently, the widespread practice of “electronic” (“computer”) cross-matching requires confirmation of the patient’s ABO/Rh blood group and a negative antibody screen, omitting the serological cross-match. After completion of PTT, the compatibility label is printed from the patient’s electronic record and attached to the red cell unit which is then issued for transfusion. In this case, PTT were performed concurrently for two patients, but the printed labels were attached to the units selected for another patient, who happened to be B RhD positive. Q2. What “checkpoints” exist between the blood bank and the patient? Would this error have been prevented if the hospital used electronic patient identification system? A2. Staff members collecting blood units from the dispensing fridge must be trained and have demonstrated their competence to collect blood. Modern electronic systems (“Blood Track”) allow access to issue fridges only to authorized and adequately trained staff and record information about the movement of blood units within the hospital. On arrival of blood to the ward, nurses (usually two registered nurses, or a nurse and a doctor) verify patient’s identity and correctness of prescription, before connecting the unit(s) to the patient. The bedside check must include checking of the bag itself, as well as the compatibility label. In the above case, the opportunity to rectify the error made by the blood bank was missed, as the ward staff (for the first unit) and the surgical theater staff (for the second unit) failed to notice that a “A RhD−” label was tagged to a bag of “B RhD+” red cells. This type of error would have been prevented if an electronic device, which scans the information encrypted in the bar code on the bag and on patient’s wristband, was available. Staff performing the check would instantly receive a warning that the scanned unit is incompatible with the patient in question.