Immunohematological testing and transfusion management of the prenatal patient.

The primary indication for immunohematological testing in the prenatal patient is to detect and identify maternal red cell antibodies. If there are antibodies that are expected to hemolyze the fetus' red cells, their strength of reactivity must be tested, and the fetus' antigen status determined. After delivery, testing is performed to assess the extent of fetomaternal hemorrhage, as a large hemorrhage may require other therapeutic interventions. Another major role for immunohematological testing is to select blood components appropriately when intrauterine transfusion is required for fetal anemia resulting from maternal alloimmunization or some other cause. Supplementation with molecular methods has transformed the practice of immunohematology, particularly as it applies to typing for the D antigen of the Rh blood group system. Notwithstanding the advances in testing, close coordination and communication between the transfusion service and the obstetrics service are the foundation for ensuring the finest care for prenatal patients, and for new mothers and their infants. This review describes testing and transfusion practices for prenatal patients, using case presentations to highlight the management of selected immunohematological findings. It also includes a discussion of key patient management topics that are currently unresolved.

Drugs and Conditions That May Mimic Hemolysis.

OBJECTIVES: Visual inspection of posttransfusion plasma for hemolysis is a key laboratory method in the investigation of possible acute hemolytic transfusion reactions (AHTRs). Many substances and physiologic conditions can mimic hemolysis in vitro. Isolated reports describe specific cases of interference, but a comprehensive listing is lacking. METHODS: Using an illustrative case, we summarize available literature on substances and conditions that may mimic hemolysis in vitro. We further describe other substances and conditions that may discolor plasma but are unlikely to be mistaken for hemolysis on visual inspection. RESULTS: At least 11 substances and conditions have been reported to discolor plasma, in colors ranging from orange to red to brown, including relatively common therapies (eg, eltrombopag, hydroxocobalamin, iron dextran). Other substances are unlikely to be encountered in everyday practice but may mimic hemolysis in particular patient populations. Additional substances may cause plasma discoloration, ranging from blue to green to white, and are associated with a wide variety of therapies and conditions. CONCLUSIONS: An awareness of the possible preanalytic confounding factors that may mimic hemolysis can aid in the workup of a suspected AHTR. Review of the medical record, use of ancillary testing, and consideration for nonimmune causes of hemolysis can aid in ruling out AHTR.

An Examination of the Intersection of Climate Change, the Physician Specialty Workforce, and Graduate Medical Education in the U.S.

Issue: As U.S. healthcare systems plan for future physician workforce needs, the systemic impacts of climate change, a worldwide environmental and health crisis, have not been factored in. The current focus on increasing the number of trained physicians and optimizing efficiencies in healthcare delivery may be insufficient. Graduate medical education (GME) priorities and training should be considered in order to prepare a climate-educated physician workforce. Evidence: We used a holistic lens to explore the available literature regarding the intersection of future physician workforce needs, GME program priorities, and resident education within the larger context of climate change. Our interinstitutional, transdisciplinary team brought perspectives from their own fields, including climate science, climate and health research, and medical education to provide recommendations for building a climate-educated physician workforce. Implications: Acknowledging and preparing for the effects of climate change on the physician workforce will require identification of workforce gaps, changes to GME program priorities, and education of trainees on the health and societal impacts of climate change. Alignment of GME training with workforce considerations and climate action and adaptation initiatives will be critical in ensuring the U.S. has a climate-educated physician workforce capable of addressing health and healthcare system challenges. This article offers a number of recommendations for physician workforce priorities, resident education, and system-level changes to better prepare for the health and health system impacts of climate change.

Prolonged Blood Storage and Risk of Posttransfusion Acute Kidney Injury.

BACKGROUND: Erythrocyte transfusions are independently associated with acute kidney injury. Kidney injury may be consequent to the progressive hematologic changes that develop during storage. This study therefore tested the hypothesis that prolonged erythrocyte storage increases posttransfusion acute kidney injury. METHODS: The Informing Fresh versus Old Red Cell Management (INFORM) trial randomized 31,497 patients to receive either the freshest or oldest available matching erythrocyte units and showed comparable mortality with both. This a priori substudy compared the incidence of posttransfusion acute kidney injury in the randomized groups. Acute kidney injury was defined by the creatinine component of the Kidney Disease: Improving Global Outcomes criteria. RESULTS: The 14,461 patients included in this substudy received 40,077 erythrocyte units. For patients who received more than one unit, the mean age of the blood units was used as the exposure. The median of the mean age of blood units transfused per patient was 11 days [interquartile range, 8, 15] in the freshest available blood group and 23 days [interquartile range, 17, 30] in the oldest available blood group. In the primary analysis, posttransfusion acute kidney injury was observed in 688 of 4,777 (14.4%) patients given the freshest available blood and 1,487 of 9,684 (15.4%) patients given the oldest available blood, with an estimated relative risk (95% CI) of 0.94 (0.86 to 1.02; P = 0.132). The secondary analysis treated blood age as a continuous variable (defined as duration of storage in days), with an estimated relative risk (95% CI) of 1.00 (0.96 to 1.04; P = 0.978) for a 10-day increase in the mean age of erythrocyte units. CONCLUSIONS: In a population of patients without severely impaired baseline renal function receiving fewer than 10 erythrocyte units, duration of blood storage had no effect on the incidence of posttransfusion acute kidney injury.

Implementation of a Quality and Patient Safety Curriculum for Pathology Residency Training.

Quality and Patient Safety education for resident physicians is necessary to prepare them for independent practice and to meet accreditation requirements. Integrating such education into the residents' routine work can provide them with valuable practical experience, while advancing the institution's quality priorities. We committed to Quality and Patient Safety education for our pathology residents but found no published program that met their specific needs. To fill this gap in pathology residency education, we designed and implemented a new curriculum that spans the 4-year duration of residency training. Curriculum content was drawn from the pathology milestones, and educational strategies were based on the principles of adult learning. The curriculum was implemented in the 2018 to 19 academic year, and residents were assessed before and after their participation. The residents engaged in several Quality and Patient Safety activities and projects under faculty supervision, and improved their scores on objective assessments (Quality and Patient Safety quiz and in-service examination). Implementation was facilitated by a Quality and Patient Safety chief resident, and the recruitment of faculty with demonstrated Quality and Patient Safety interest. Our comprehensive Quality and Patient Safety curriculum is feasible to implement and can help pathology residents develop the knowledge and skills needed to lead quality initiatives. We believe that the curriculum framework is readily adaptable to other residency programs.

Implementation of a Standardized Prenatal Testing Protocol in an Integrated, Multihospital Health System.

OBJECTIVES: When our institution grew into an integrated multihospital health system, we were faced with the need to standardize laboratory processes, including blood bank processes, across all locations. The purpose of this article is to describe our experience of standardizing the protocols for prenatal testing. METHODS: For each hospital in the system, we established service tiers to define tests offered on site or referred to another location. For each prenatal test, we examined the related processes for ways to improve uniformity, efficiency, and reliability. Throughout this process of standardization, we collaborated with the clinical services to gain concurrence on the interpretation and reporting of results. RESULTS: We created and implemented a uniform protocol for testing prenatal patients. The protocol standardized the definition of critical titer, instituted criteria to identify passively acquired anti-D, and established a process for the follow-up of women with inconsistent serologic results on Rh(D) typing. CONCLUSIONS: Close collaboration with the clinical services ensured that our testing protocol is aligned with the needs of the integrated obstetrics service in the health system. The approach described in this article may provide a plan outline for pathologists facing similar challenges at other integrated health systems.

Cold Antibodies in Cardiovascular Surgery: Is Preoperative Screening Necessary?

OBJECTIVES: Cold antibodies (CAs) are rarely significant for transfusion, but they can cause complications under the hypothermic conditions of cardiovascular surgery. The purpose of this study was to determine the incidence of such complications. METHODS: Patients with CAs who underwent cardiovascular surgery were identified, and their records were reviewed for intraoperative complications attributable to CAs. RESULTS: Over 14.5 years, of the 47,373 patients who underwent cardiovascular surgery, 99 had CAs before or within 30 days after surgery. Ninety-seven patients had hypothermic surgery, and intraoperative agglutination was noted in four; two of these cases were never reported to the transfusion service. CONCLUSIONS: The incidence of intraoperative complications among our patients with CAs was only 4%; therefore, the use of special testing protocols for the preoperative identification of CAs is neither necessary nor justified. Patient risk is best managed by preoperative clinical evaluation for potentially pathogenic CAs and intraoperative vigilance for agglutination.

How do we use molecular red blood cell antigen typing to supplement pretransfusion testing?

The molecular basis of many blood group antigens is known, and it provides a means for predicting the red blood cell phenotype. Molecular typing methods are useful when serologic typing cannot be performed, due to sample or reagent limitations. We discuss the implementation of a commercial molecular typing assay at our Transfusion Service, the indications for testing, and the advantages and drawbacks of the assay. We also present our algorithm for selecting candidates for testing.

Bacterial contamination of whole-blood-derived platelets: the introduction of sample diversion and prestorage pooling with culture testing in the American Red Cross.

BACKGROUND: Bacterial sepsis following whole blood-derived platelet (WBP) transfusion has remained a substantial patient risk, primarily due to a lack of practical and effective means to limit or detect bacterial contamination. We describe the risk of reported septic reactions to WBPs and the introduction of prestorage-pooled whole blood-derived platelets (PSPs) collected using initial sample diversion and cultured for bacterial contamination. STUDY DESIGN AND METHODS: Product qualification and quality control (QC) testing with the Acrodose PL system (Pall Medical) were evaluated in four regional blood centers. Bacterial contamination risk was assessed by review of reported septic transfusion reactions to WBPs and by aerobic QC culture of leukoreduced PSPs utilizing automated microbial detection system cultures (BacT/ALERT 3D, bioMérieux). RESULTS: Before implementing PSPs (January 2003-December 2006), we distributed 2,535,043 WBP units and received 20 reports of septic reactions including 2 fatalities (7.9 per million [1:126,752] reactions and 0.79 per million [1:1,267,522] fatalities). In October 2006, PSPs were effectively implemented with a product qualification success rate of 99.6 percent and a mean yield of 4.0 x 10(11) platelets (PLTs) per pool. Whole blood collection sets with sample diversion technology were introduced during the operational trial and decreased the rate of confirmed-positive bacterial culture of PSPs from 2111 (1:474) to 965 (1:1036) per million (odds ratio, 0.46; 95% confidence interval, 0.22-0.95). No septic reactions to PSPs were reported (25,936 PSP units distributed). CONCLUSION: Sample diversion and bacterial culture are effective methods to reduce bacterial risk with WBP transfusion. Bacterial contamination of PSPs was assessed at 5.8-fold our current rate for apheresis PLTs utilizing comparable culture protocols.

Acute hemolytic transfusion reaction in a pediatric patient following transfusion of apheresis platelets.

The practice of transfusing ABO-incompatible platelets, driven primarily by concerns about inventory management, has been considered generally safe because the accompanying plasma is usually diluted in the recipient's total blood volume. However, if the platelet product contains a large volume of plasma or a high concentration of incompatible isoagglutinin, there may be hemolysis of the recipient's red cells. Patients with a small blood volume, such as babies and children, are considered to be at particular risk for such a complication. We describe the case of a baby who suffered massive hemolysis of her group A red cells after transfusion of group O Apheresis Platelets containing a high-titered anti-A isoagglutinin. We also offer a review of the literature on this subject and recommendations to avoid acute hemolytic reactions as a result of platelet transfusion.