Anemia, Apnea of Prematurity, and Blood Transfusions

Abstract

Objective To compare the frequency and severity of apneic events in very low birth weight (VLBW) infants before and after blood transfusions using continuous electronic waveform analysis. Study design We continuously collected waveform, heart rate, and oxygen saturation data from patients in all 45 neonatal intensive care unit beds at the University of Virginia for 120 weeks. Central apneas were detected using continuous computer processing of chest impedance, electrocardiographic, and oximetry signals. Apnea was defined as respiratory pauses of >10, >20, and >30 seconds when accompanied by bradycardia (<100 beats per minute) and hypoxemia (<80% oxyhemoglobin saturation as detected by pulse oximetry). Times of packed red blood cell transfusions were determined from bedside charts. Two cohorts were analyzed. In the transfusion cohort, waveforms were analyzed for 3 days before and after the transfusion for all VLBW infants who received a blood transfusion while also breathing spontaneously. Mean apnea rates for the previous 12 hours were quantified and differences for 12 hours before and after transfusion were compared. In the hematocrit cohort, 1453 hematocrit values from all VLBW infants admitted and breathing spontaneously during the time period were retrieved, and the association of hematocrit and apnea in the next 12 hours was tested using logistic regression. Results Sixty-seven infants had 110 blood transfusions during times when complete monitoring data were available. Transfusion was associated with fewer computer-detected apneic events (P < .01). Probability of future apnea occurring within 12 hours increased with decreasing hematocrit values (P < .001). Conclusions Blood transfusions are associated with decreased apnea in VLBW infants, and apneas are less frequent at higher hematocrits.

Apnea of Prematurity

“…25,26 A recent study that used a novel computer algorithm to detect apnea, bradycardia, and oxygen desaturation in continuously recorded physiologic data from 67 preterm infants showed decreased apnea for the 3 days after blood transfusions compared with 3 days before. 27 These authors also reported that the probability of an apnea event in a 12-hour epoch was higher with a lower hematocrit, adjusted for PMA. These results suggest that anemia may increase the likelihood of apnea of prematurity and that blood transfusions may result in a short-term reduction in apnea.…”

Apnea of prematurity: challenges and solutions

“…The likelihood of having apnea in the 12 hours following transfusion was related to hematocrit. 54 Despite not being able to consider red blood cell transfusion as a treatment for moderately anemic infants with AOP, this option should be evaluated on a case by case basis.…”

Time to Delay: A Literature Review of Delayed Cord Clamping

“…When indicated, transfusions decrease apnea of prematurity [40,41], may decrease neurologic adverse effects [42], and improved cerebral oxygen delivery, which may improve neuro developmental outcome [43]. DCC may also decrease the need for neonatal transfusions.…”