Early warning for SpO2 decrease by the oxygen reserve index in neonates and small infants.

INTRODUCTION: Continuously assessing the oxygenation levels of patients to detect and prevent hypoxemia can be advantageous for safe anesthesia, especially in neonates and small infants. The oxygen reserve index (ORI) is a new parameter that can assess oxygenation through a relationship with arterial oxygen partial pressure (PaO2 ). The aim of this study was to examine whether the ORI provides a clinically relevant warning time for an impending SpO2 (pulse oximetry hemoglobin saturation) reduction in neonates and small infants. METHODS: ORI and SpO2 were measured continuously in infants aged <2 years during general anesthesia. The warning time and sensitivity of different ORI alarms for detecting impending SpO2 decrease were calculated. Subsequently, the agreement of the ORI and PaO2 with blood gas analyses was assessed. RESULTS: The ORI of 100 small infants and neonates with a median age of 9 months (min-max, 0-21 months) and weight of 8.35 kg (min-max, 2-13 kg) were measured. For the ORI/PaO2 correlation, 54 blood gas analyses were performed. The warning time and sensitivity of the preset ORI alarm during the entire duration of anesthesia were 84 s (25th-75th percentile, 56-102 s) and 55% (95% CI 52%-58%), and those during anesthesia induction were 63 s (40-82 s) and 56% (44%-68%), respectively. The positive predictive value of the preset ORI alarm were 18% (95% CI 17%-20%; entire duration of anesthesia) and 27% (95% CI 21%-35%; during anesthesia induction). The agreement of PaO2 intervals with the ORI intervals was poor, with a kappa of 0.00 (95% CI = [-0.18; 0.18]). The weight (p = .0129) and height (p = .0376) of the infants and neonates were correlated to the correct classification of the PaO2 interval with the ORI interval. CONCLUSIONS: The ORI provided an early warning time for detecting an impending SpO2 decrease in small infants and neonates in the defined interval in this study. However, the sensitivity of ORI to forewarn a SpO2 decrease and the agreement of the ORI with PaO2 intervals in this real-life scenario were too poor to recommend the ORI as a useful early warning indicator for this age group.

Current hemoglobin thresholds in pediatric anesthesia - guidelines and studies.

PURPOSE OF REVIEW: The use of restrictive transfusion triggers to avoid unnecessary transfusions is one important pillar of Patient Blood Management (PBM). For the safe application of this principle in pediatric patients, anesthesiologists need evidence-based guidelines for hemoglobin (Hb) transfusions thresholds in this specially vulnerable age-group. RECENT FINDINGS: This review outlines recent prospective and observational studies examining transfusion thresholds in pediatrics. Recommendations to use transfusion triggers in the perioperative or intensive care setting are summarized. SUMMARY: Two high-quality studies confirmed that the use of restrictive transfusion triggers in preterm infants in the intensive care unit (ICU) is reasonable and feasible. Unfortunately, no recent prospective study could be found investigating intraoperative transfusion triggers. Some observational studies showed wide variability in Hb levels before transfusion, a tendency toward restrictive transfusion practices in preterm infants, and liberal transfusion practices in older infants. Although there are comprehensive and useful guidelines for clinical practice in pediatric transfusion, most of them do not cover the intraoperative period in particular because of a lack of high-quality studies. This lack of prospective randomized trials focusing on intraoperative transfusion management remains a major problem for the application of pediatric PBM.