Visual Light Spectrography (VLS) for Detecting Alterations in Tissue Oxygenation with Administration of Packed Red Blood Cells (PRBC) in Very Low Birth Weight (VLBW) Premature Infants

Background: Sixty to eighty percent of all VLBW infants receive PRBC transfusions with a goal of improving tissue oxygen delivery. Yet no firm consensus exists regarding individual- ized Hb trigger levels or the best method to assess the efficacy of blood transfusion. Clini- cal signs and blood tests are late indicators and the latter contribute to iatrogenic anemia. Visible light spectroscopy (VLS) can non- invasively assess tissue saturation (StO2) in small segments of tissue and reliably obtain recording during poor perfusion states. Objective: To investigate the effect of PRBC on StO2 in patients with anemia. Design/Methods: Tissue oxygen and pulse oximeter saturations were measured continu- ously and compared at the following time ep- ochs: 1 hour before, at the beginning, hourly during and 1 hour after blood transfusion. The difference between pulse and tissue satura- tion was calculated ( P= SpO2 - StO2), as a marker of tissue perfusion. Vital signs and Neonatal Therapeutic Intervention Scoring System (NTISS) severity of the disease scores were assessed. Results: Five neonates without evidence of hypovolemia receiving PRBC transfusions to increase RBC mass were studied. Despite an absence of changes in vital signs and SpO2, there was statistically significant decrease in tissue oxygenation and worsening of pulse (P) at 2nd, 3rd and 4th hours of transfusion indicating compromised tissue oxygenation. Conclusions: The decrease in StO2 and increase in P during blood transfusion was �