P065: THE ROLE OF SUPPLEMENTAL OXYGEN AND TISSUE OXYGENATION MONITORING IN MANAGEMENT OF SEVERE POST-OPERATIVE ANEMIA IN JEHOVAH'S WITNESS
Jose Navas, MD; Roman Dudaryk, MD; University of Miami
Introduction: Perioperative management of Jehovah's Witnesses aimed to optimize oxygen delivery in the settings of severe anemia remains a challenge for clinicians. We describe a case of a 78-year-old Jehovah's Witness patient with profound post-operative anemia following a total hip replacement. Near-infrared spectroscopy was employed to assess tissue oxygenation and monitor the effects of oxygen delivery at room air and high fraction of inspired oxygen.
Case Report: A 78-year-old male Jehovah's Witness underwent right total hip replacement. Preoperative hemoglobin and hematocrit values were 12.1g/dL and 36.9%, respectively. Patient had an uneventful intraoperative course and blood loss was estimated at 200-mL. He was extubated in the operating room and then sent to the intermediate care per routine hospital protocol. His initial post-operative course was uncomplicated, and he was transferred to a surgical ward by the orthopedic team on post-operative day (POD) #1. No further blood draws were indicated at this point.
He continued to make appropriate progress, working with physical therapy and increasing his functional capacity until POD#6 when he complained a vague feeling of confusion. Further laboratory evaluation revealed a normocytic/normochromic anemia with hemoglobin and hematocrit levels of 4.2g/dL and 13.4%, respectively. The patient was transferred to the Intensive Care Unit (ICU) for further management and monitoring. Initial evaluation revealed a patient hemodynamically stable, alert and oriented with intact neurologic examination and adequate oxygen saturation levels at room air. An assessment of systemic (SpO2 and ABGs) and tissue oxygenation (skeletal: StO2 and cerebral: rSO2) was undertaken both at room air and 100% oxygen via a non-rebreather mask. NIRS was used to measure tissue oxygenation: StO2 was measured using InSpectra (Hutchinson, MN, USA) on the thenar eminence, and brain oximetry was performed with INVOs (Somanetics, Medtronics, USA) over frontal lobes bilaterally.
Regardless of inspired oxygen concentration, the patient SpO2 remained at 100%. There was no evidence of lactic acidosis or a base deficit in the ABGs. The rSO2 of the patient at baseline on room air was at 38%, which is significantly below the normal range of 55-78%. With supplemental oxygenation, rSO2 increased from 38% to 41% partially correcting the low saturation level. Similarly, his StO2 measured over the thenar eminence on room air was 65%, below the normal range of 75-91%. With supplemental 100% oxygen, StO2 corrected, increasing to mid-normal range of 82%.
The patient remained otherwise stable, other than a complaint of mild fatigue. Limited blood draws were performed, and no blood products were administered during the rest of his hospital stay. He was sent back to the floor on POD#8, and subsequently discharged on POD#17 with hemoglobin and hematocrit values of 7.5g/dl and 24.5% respectively.
Conclusion: Regional indices of oxygen saturation might better represent tissue well-being. At the same time, the presence of low regional oxygenation values is not synonymous of tissue hypoxia. Monitoring of tissue oxygenation may be used as a potential surrogate for hemoglobin content particularly when limited blood draws are needed.