Units Of Packed Red Blood Cells Research Articles

Neonatal mortality following transfusion of red cells with high plasma potassium levels

The death of a neonatal infant following cardiac surgery and the transfusion of packed red cells (RBCs) with high plasma potassium levels is reported. The patient had been diagnosed at 2 weeks of age as having multiple cardiac malformations. During cardiopulmonary bypass surgery, multiple units of packed RBCs less than 5 days old were transfused. In response to a "stat" order and after depletion of stock units prepared for neonatal usage, a 32-day-old unit of packed RBCs was issued for transfusion. After approximately 60 mL was rapidly transfused from this unit, the patient experienced cardiac arrest. Serum potassium concentration after transfusion and before death was 8.9 mmol per L. Plasma potassium concentration in the remainder of the transfused packed RBC unit was approximately 60 mmol per L. A model was created to calculate the posttransfusion plasma potassium concentration, and close correlation was found between the model and the observed potassium concentration, which assumes that the potassium load had not yet been distributed to the extravascular and intracellular fluid compartments. It is concluded that the transfusion of relatively large volumes of RBCs be limited to fresh packed RBCs or to packed RBCs that have been saline washed, to minimize the complications of electrolyte disturbances.

Decreasing transfusion exposure risk during extracorporeal membrane oxygenation (ECMO).

Extracorporeal membrane oxygenation (ECMO) is a lifesaving therapy for neonatal pulmonary hypertension but carries a significant risk for transfusion-related complications. Packed red blood cell (PRBC) and platelet exposure were quantified and reviewed in 17 ECMO survivors prior (Group I, n = 9) and subsequent to (Group II, n = 8) changes in transfusion protocols. Blood product requirements included ECMO circuit priming, maintenance of haematocrit > 0.40 or platelet count > 50 x 10(9)/l, and colloid volume expansion. Group I was exposed to 13.8 +/- 10.2 (x +/- SD) different PRBC units. In Group II, multiple transfusions from single donor units decreased exposure 71% to 3.9 +/- 0.7 units (P < 0.05). Decreases in blood withdrawn (11%) and transfusion volume (7%) were coincident with a 15% reduction in mean bypass time. Platelet volume transfusion decreased from 159 +/- 213 to 93 +/- 64 ml using volume-reduced platelet packs. Total transfusion exposure decreased 59% from 20.8 +/- 17.8 units to 8.6 +/- 2.4 donor units. No transfusion complications occurred during the aggregate 1,926 h on bypass. We conclude that neonates on ECMO have a significant transfusion exposure risk increasing with prolonged duration of ECMO therapy. In addition we noted that concentrated platelet packs decreased transfusion volume by 41%, and multiple PRBC transfusions from single donor units decreased donor exposure by 71% while both strategies decreased the overall transfusion exposure risk by 59%.

Contrôle bactériologique de 1 000 concentrés de globules rouges humains à la recherche de Yersinia enterocolitica

Several reports of Yersinia enterocolitica (Ye) post-transfusion septicaemia have been recently published. In order to study the prevalence of Ye contamination of packed red blood cells (PRBC) we performed a post-transfusion control on 1,000 PRBC units. We did not find any Ye contamination. This is in accordance with the rarity of the reported cases. However as they are very serious, a prevention is necessary. As classical bacteriological techniques are not feasible, the only possibility is to decrease the PRBC conservation time and to select blood donors by a careful questioning about recent GI tract disturbances.

Effects of room‐temperature exposure on bacterial growth in stored red cells

Experiments were performed to determine the effect of room-temperature (RT) exposure on the growth rates of selected bacteria by deliberate contamination of AS-1 packed red cell (RBC) units contained in PL146 plastic bags. Isolates of Staphylococcus aureus, S. epidermidis, Streptococcus faecalis, Pseudomonas aeruginosa, Citrobacter freundii, Enterobacter agglomerans, and Yersinia enterocolitica were inoculated into 3- to 5-day-old packed RBC units. The units were refrigerated at 4 to 6 degrees C for 14 days. On two occasions during this period, one-half of the units were removed from the refrigerator and held at 25 to 26 degrees C for 2 hours. Timed samples taken during the periods at RT revealed stable or decreasing bacterial counts in the majority of exposed units, and in no instance was a marked increase in bacterial growth observed. Samples taken after subsequent prolonged rerefrigeration showed no significant increase in bacterial counts as compared with those in control units that were refrigerated constantly. These results indicate that RT exposure of contaminated RBC units does not result in accelerated bacterial proliferation over a period of 2 hours and that it may, in fact, have a detrimental effect on bacterial growth.

Rapid warming and infusion of packed red blood cells

A four-part experiment was undertaken to determine the feasibility of adding normal saline warmed to 45 C to units of packed red blood cells (PRBCs) to warm them and increase blood flow in transfusions. In Part One, the flows of fresh and outdated PRBCs through a modified infusion system were compared. The results showed that there was no significant difference in flow rates and between fresh (11.5 gm/min +/- 0.98 SD) and outdated (10.08 gm/min +/- 1.45 SD) PRBCs using the Student t test for uneven groups. This allowed outdated PRBCs to be used in place of fresh for a good portion of the experiment. In Part Two, PRBCs were run through a Travenol blood warmer coil (Travenol Laboratories, Deerfield, Illinois), and flow rate was 5.17 gm/min (+/- 0.61 SD) with delivery temperature of 29 C (+/- 1.58 SD). In Part Three normal saline warmed to 45 C was added to units of PRBCs, and flow rate was 57.72 gm/min (+/- 0.61 SD) with delivery temperature of 26 C (+/- 1.49 SD). In Part Four normal saline warmed to 45 C was added to units of PRBCs as in Part Three and then run through the blood warmer. The flow rate was 18.23 gm/min (+/- 3.44 SD) with delivery temperature of 35.3 C (+/- 1.45 SD). Plasma hemoglobins also were determined on fresh PRBCs before and after addition of warmed normal saline and passage through the blood warmer. There was no evidence of significant hemolysis of the blood due to this technique.(ABSTRACT TRUNCATED AT 250 WORDS)

A revised rule of thumb for predicting haematocrit rise in premature infants following packed red blood cell transfusion.

The purpose of this study is to compare a revised rule of thumb with the Harriet Lane and Behrman's formulas for predicting haematocrit rise following packed red blood cell (PRBC) transfusion in premature neonates. Pre- and post-transfusion, equilibrated central haematocrits were obtained within 24 h of transfusion in 12 premature neonates undergoing 18 transfusions. Iatrogenic blood loss between pre- and post-transfusion haematocrit determinations was measured for each transfusion event, and infants with detectable, non-iatrogenic blood loss were excluded. Expected haematocrit rise was calculated three different ways using the Behrman, Harriet Lane, and proposed formulas (see text). The Harriet Lane formula predicted haematocrit rise with a correlation, r = 0.66 and slope m = 0.43. The Behrman's formula predicted haematocrit rise with a correlation r = 0.81 and slope m = 0.60. The proposed formula predicted haematocrit rise with a correlation r = 0.79 and slope m = 0.56. On the basis of these findings, we propose the following formula: Quantity PRBC transfused (ml) = 4/3 X desired haematocrit rise X weight (Kg) This formula takes into account the higher blood volume per kilogram body weight seen in premature infants while estimating PRBC unit haematocrit as 0.75 to obviate the need of measurement before each transfusion and, therefore, is an accurate, practical, and simple replacement for the Harriet Lane and Behrman's formulas.

Blood Conservation during Open Heart Surgery in Infants and Children

We studied 211 consecutive patients (age 1/12 to 18 7/12 years, median 2 3/12 years; weight 2 to 70 kg., median 11.2 kg.) undergoing cardiopulmonary bypass (CPB) for repair of congenital heart defects from September 1978 to September 1982 to determine blood used at surgery and within 48 hours of operation. There were 10/211 (4.7%) peri-operative deaths and 21 patients bled more than 500 cc from chest tubes during the first twelve hours post-op; 4 ( 4/211 = 1.9%) required re-exploration. This left 180 uncomplicated cases. From 1978 to 1982: (1) The average number of units of packed red blood cells (PRC) used per patient decreased from 4.3 to 1.9 for the entire patient population and from 4.1 to 1.2 for uncomplicated cases; (2) the average number of PRC units used for CPB prime decreased from 1.9 to 0.5; and (3) average end-CPB hematocrit decreased from 27.9 to 22.6%. All differences are highly significant (p 0.001). Peri-operative and postoperative morbidity were unchanged over the course of the study. In 1982, 23/48 (48%) cases used nonblood prime (weight 8.8 to 70 kig., median 27.0 kg.; median pre-op Hct 45.0%) and 25/48 (52%) cases used 1 unit (weight 3.5 to 16.6 kg., median 9.0 kg.; median pre-op Hct 37.1 %). Through a conscious effort to conserve blood, we substantially reduced our banked blood requirements for congenital heart surgery. Blood conservation reduces cost, spares resources, and minimizes risk of transfusion reaction and infectious disease, but does not increase the morbidity of congenital heart surgery.

Mesenteric angiography.

AIM: To assess if certain triaging rules could be established to optimize the yield of mesenteric angiography. METHODS: Medical records of 101 patients were retrospectively reviewed and parameters relating to age, gender, pulse rate, blood pressure, serum hemoglobin, intensive care unit(ICU) admission, and the number of packed red blood cells(PRBC) transfused in the 12 and 24 h prior to the angiography were tabulated in two groups with positive and negative angiography results. RESULTS: We found no correlation between gender, pulse rate, blood pressure or serum hemoglobin and positivity of the mesenteric angiogram. But patients with positive angiogram were found to be on average 7 years older(73.2 years vs 65.9 years old)(P = 0.02). Angiogram was positive in 39.3 %(11/28) of patientsadmitted in ICU vs 23.2%(17/73) who were admitted elsewhere in the hospital(P = 0.03). In the 12 and 24 h prior to angiography, patients with a positive angiogram received a mean of 2.7 ± 2.3 and 3.3 ± 2.6 units of PRBC s respectively, while patients with a negative angiogram had a mean of 1.6 ± 1.9(P = 0.02) and 2.1 ± 2.6 units(P = 0.04) received respectively in the same period. CONCLUSION: Older age, ICU admission, having received at least 4 units PRBC over 12 h or 5 units over 24 h prior to angiogram are leading indicators for a positive study.