Transfusion-Transmitted Diseases

Viruses

Transfusion transmission of HIV, HCV, and HBV is “now so rare that the rate of transmission cannot be measured by prospective studies . . . only estimated by theoretical modeling” (Crowder et al., 2020). The estimated risks given in Table 11-8 are based on calculations.

Cytomegalovirus

CMV is a virus belonging to the herpes group that can be transmitted from a blood transfusion, primarily from WBCs present in blood components. Most adults have been exposed to CMV because the majority of blood donors have CMV antibodies (Crowder et al., 2020). CMV infection usually is mild but may be serious or fatal for those who are immunocompromised, for low-birth weight infants, and for bone marrow and organ transplant patients. Patients at risk for CMV infection should receive blood components from donors who are CMV-negative or components that are leukocyte reduced.

Bacteria

Bacterial contamination of blood components, mainly platelets, continues to cause transfusion-related death, after TRALI and hemolytic reactions (Crowder et al., 2020). Sources of bacteria include the donor's skin and asymptomatic bacteria in the donor's bloodstream. Immediately following blood collection, the level of bacteria is too low to detect or cause recipient symptoms. However, the bacteria proliferate during storage. Because platelets are stored at room temperature, the associated risk is greatest.

Attention to skin antisepsis during venipuncture preceding blood donation is a critical step. Most often, two-stage procedures involving use of chlorhexidine, alcohol, and iodophors (e.g., Betadine) are used in skin antisepsis. Also, “diversion pouches” are used to discard the first 40 mL or more of donor blood away from the blood collection container. This is required for all platelet collections and for whole blood collection where platelets are extracted (Crowder et al., 2020). There are additional methods used to detect the presence of bacteria in platelets as part of quality control. Refrigerated storage limits the growth and viability of most bacteria in RBC products.

Prions

Prions are proteinaceous infectious particles that cause fatal infections of the nervous system called transmissible spongiform encephalopathies (TSEs). The best-known TSE disease in humans is Creutzfeldt-Jakob disease (CJD). This is a rare degenerative and fatal nervous system disorder. CJD has been transmitted via infusion or implantation of devices extracted from infected central nervous system tissues but has not been known to be transmissible via blood transfusion (Crowder et al., 2020). Although there is no screening test for the disease, as a precaution the FDA prohibits blood donation by individuals who may be at risk. These include potential donors who have a family history of CJD, and those who have undergone surgeries that involved transplanted dura mater.

Similar to CJD, variant CJD (vCJD), commonly known as the human form of “mad cow” disease, is a rare degenerative and fatal nervous system disorder. There have been four cases of vCJD transmission via blood transfusions; these occurred in the United Kingdom, where bovine spongiform encephalopathy (i.e., mad cow disease) is most endemic (Crowder et al., 2020). There have been no cases of transmission in the United States. Screening for risk is via questioning, and any patients at risk are excluded.

Infections Transmitted by Insect Vectors

West Nile Virus

WNV is spread by the bite of an infected mosquito. The virus can infect people, horses, and many types of birds. It was first detected in the United States in 1999, and the first documented cases of WNV transmission through organ transplantation and transfusion were noted in 2002. The most common symptoms of transfusion-transmitted WNV are fever and headache. Screening is by transfusion service interview for history of fever and headache. Blood screening with nucleic acid amplification testing (NAAT) for WNV is now required by both the AABB and the FDA (Crowder et al., 2020).

Parasitic Infections

A variety of parasitic infections may be transmitted through transfusions:

• Babesia: These are intraerythrocyte parasites; infections are acquired through tick bites. In many individuals there are no symptoms; however, in immunocompromised, elderly, and asplenic patients, infection may present as a fatal flu-like illness.
• Trypanosoma cruzi: This is a protozoan parasite that causes Chagas disease, which is usually a self-limited disease but can be severe in immunocompromised individuals. A blood donor screening test was widely implemented across the United States in 2007 (Crowder et al., 2020).
• Malaria: There is no FDA-approved test. Malaria is rare in the United States, and the blood supply has been effectively protected by donor questioning.

AGE-RELATED CONSIDERATIONS

Neonatal and Pediatric Patients

Special guidelines must be applied to neonatal and pediatric patients. The most significant differences between this young group and adults are:

• Smaller blood volume. Blood volumes for pediatric patients vary with body weight. A newborn has a blood volume of approximately 85 mL/kg. Transfusion services must be capable of providing smaller, appropriately sized blood components to meet the needs of this population.
• Because of their smaller volume of blood, neonatal and pediatric patients have a decreased ability to tolerate blood loss.
• Neonatal and pediatric patients have immature organ function (Wong & Punzalan, 2020).

Sick neonates with anemia are more likely to receive RBC infusions than any other age group (Wong & Punzalan, 2020). Iatrogenic blood loss from repeated phlebotomy can lead to frequent transfusions and attention to blood loss from laboratory testing is critical, as outlined in Table 11-6. Transfusion is based on the presence of symptomatic anemia or target Hct levels.

Transfusion Administration Issues

The most difficult aspect of transfusion in those younger than 4 months is vascular access. The umbilical vein is most frequently used for fluids and transfusions in preterm and term infants just after birth; small-gauge catheters (24) or needles (25) can be safely used without causing hemolysis (Wong & Punzalan, 2020).

Because rate control with small-volume and slow-rate transfusions is important, the use of infusion pumps, such as syringe pumps, is common in the neonatal/pediatric population. As discussed earlier, the manufacturer's infusion pump instructions should be reviewed to ensure the pump is safe to use with blood and blood products. Blood warmers are not routinely used.

Standard filtration using filters between 170 and 260 microns is required, as it is with adults. There are special pediatric transfusion administration sets that have less dead space than a standard set.

The Older Adult

The older adult receiving transfusion therapy is at increased risk for TACO. Nursing interventions include careful monitoring of intake and output, laboratory test results, daily weight, and assessment of pulmonary and renal function.

Home Care Issues

In the 1980s, transfusing blood (i.e., RBCs, platelets) in the home-care setting was not uncommon. Such programs required extensive planning, relationships with blood centers, emergency plans and availability of emergency medications, and great attention to nurse education and competency. Today such programs are not common. The reality is that with today's focus on blood management and available alternatives to blood transfusion, there is limited need for home-based transfusion programs. Outside of the hospital, outpatient settings such as oncology clinics are more likely and more appropriate settings for transfusing the nonhospitalized patient. Notably, the AABB provides a publication entitled Standards for Out-of-Hospital Transfusion Administration Services, first edition (https://www.aabb.org) However, there are some blood component infusion therapies that are appropriate for home administration, such as factor replacement for patients with hemophilia. In the case of factor replacement, such infusions are often either administered in the home by a nurse or self-infused by the patient, using recombinant, rather than plasma-derived, products. The role of the home-care nurse is important in providing patient education and in identifying and reporting signs and symptoms of delayed transfusion reactions (e.g., delayed hemolytic transfusion reaction) for patients who have received recent transfusions.

Patient Education

Patients who are aware of the steps involved in a transfusion experience less anxiety. Explain how the transfusion will be given, how long it will take, what the expected outcome is, and what symptoms to report; also tell the patient that vital signs will be taken. The provider has the responsibility to explain the benefits and risks of transfusion therapy as well as the alternatives and options (e.g., autologous, homologous, or directed donation) as part of the informed consent process.