Adverse Donor Reactions

Hematoma

About 30% of donors have an arm complication: 23% report bruise (contusion/hematoma) and 10% pain. These complications can result in pain, swelling, tenderness, redness, and warmth. They can be treated with warm compresses and mild analgesics and generally resolve completely within 7–14 days.

Nerve Injury

Nerve injury incidence by active follow up is 0.9%, but 0.16% by voluntary postdonation reports. Complaints include sensory changes in the forearm, wrist, hand, or shoulder and radiating pain. 15% of affected donors will also report decreased arm or hand strength. Chronic nerve damage from the phlebotomy needle is an unusual event, yet interaction of the phlebotomy needle with branches of superficial nerve branches likely occurs frequently from a study of cadavers. Nerve injury is usually transient: 70% disappear within a month, >99% resolve within one year. Rare cases of complex regional pain syndrome (reflex sympathetic dystrophy) have been reported.

Vasovagal

Vasovagal reaction occurs in 2%–30% donations, depending on donor group with wide variation among reporting centers. Predisposing factors include first-time donors, donors with low weight, and history of previous donor adverse reaction. In a recent study of high school donors, anticipatory fear and length of draw time were strongest predictors of observed reaction rates. For donors with >10-minute draw time, observed reaction rates were 31% among donors self-reporting fear versus 10% for those denying fear. For draw times less than 6 minutes, the reported rates were 16% versus 5%, respectively.

Proposed mechanisms for higher rates in young and first-time donors include changes in central thalamic pathways, vascular baroreceptor sensitivity, and age-dependent responses to physical and emotional stress. Anxiety related to blood donation, blood or needles in general contribute to vasovagal reactions, as they can precipitate the reaction even before donation, and clusters of fainting (“epidemic fainting”) can occur when prospective donors witness an untoward event at a blood drive. Asking donors about their fears does not increase the rate of reaction and indeed allows staff to focus distraction techniques on fearful donors at highest risk of reactions.

Symptoms include chills or cold extremities, feeling of warmth, light-headedness, nausea, pallor, weakness, hyperventilation, and declaration of nervousness. Signs include hypotension, rapid or slow pulse, sweating, and twitching. Vasovagal reactions can progress to LOC and seizure-like activity (tonic–clonic movements, tetany, with loss of bladder or bowel control). Vasovagal events are classified as prefaint, no LOC (uncomplicated or minor), LOC (uncomplicated), LOC (complicated), and injury.

Interventions include the following: asking about fear and offering distraction, calmness and reassurance, elevation of the donor’s legs above the heart, ensuring donor is lying down or in safe place in case of fainting, cold compresses to the neck or forehead, and monitoring blood pressure, pulse, and respirations (vital signs) periodically until recovery.

Prolonged Recovery

Prolonged recovery is defined as presyncopal symptoms, with or without LOC, that do not resolve within 30 minutes. If the donor has not recovered or has unstable vital signs during the typical 5–30 minutes expected for complete recovery, most blood collection centers not located within a hospital (in the United States) will call 911 for emergency medical services (EMS) response. Staff members should also notify both their facility medical director either before or after the 911 call and local host site, depending on the severity of symptoms and/or resulting injury that occurs.

Arterial Puncture

Arterial puncture occurs at a rate of 1/34,000 donations and is more common among inexperienced phlebotomists than those with experience. Most common indicator is rapid filling of collection bag, total phlebotomy time of less than 4 minutes and bright red color of blood. This event can occur with the initial puncture, or after needle adjustment. Proper treatment requires immediate needle removal and prolonged application of pressure at injury and arm elevation. Rarely, pseudoaneurysms develop at the site of arterial punctures.

Iron Loss

Whole blood or red blood cell (RBC) donation results in iron loss (200–250 mg of iron per 500 mL of blood or 250 mL of RBCs). Repeated donation correlates with iron store depletion. Symptoms of iron deficiency include pica, typically craving of ice (pagophagia), feeling weak or tired, difficulty concentrating, dyspnea, light-headedness, and possibly restless leg syndrome. In the RISE (REDS-II Donor Iron Status Evaluation) study, 15% of frequent whole blood donors had absent iron stores (AIS, defined as ferritin <12 ng/mL) and 42% had iron deficiency anemia (IDE, defined as log of ratio of soluble transferrin receptor to ferritin was ≥2.07): 0% and 2.5% of first-time/male donors had AIS and IDE, respectively; 6% and 25% of first-time/reactivated females had AIS and IDE, respectively; 16% and 49% of frequent males had AIS and IDE, respectively; and 27% and 66% of frequent females had AIS and IDE, respectively. Young donors have a higher baseline rate of low iron stores and are therefore at particular risk of early depletion. Subsequent studies have documented that iron replacement dramatically shortens time to both time to return to baseline hemoglobin and recovery of iron stores. Low dose of iron (18–19 mg), typically found in multivitamins with iron, was equivalent to higher doses and had minimal side effects. Blood centers are introducing programs to educate donors, measure ferritin, or provide iron replacement to those with documented or at risk for low iron stores, such as frequent donors or younger females.