Changes in Cerebral Regional Oxygen Saturation Variability in Neonates Undergoing Cardiac Surgery: A Prospective Cohort Study.

Near-infrared spectroscopy is routinely used in the monitoring of cerebral regional oxygen saturation (crSO2) in neonates following congenital heart surgery. Decreased postoperative crSO2 variability in these patients is associated with worse clinical outcomes, including neurodevelopmental outcomes. We sought to explore changes in crSO2 variability between the preoperative and postoperative periods and associations with short-term clinical outcomes in neonates undergoing cardiac surgery. We performed a prospective cohort study of neonates undergoing cardiac surgery with cardiopulmonary bypass between November 2019 and May 2021. We calculated crSO2 variability using averaged 1 min of crSO2 values for a minimum of 12 h before, and the first 48 h following surgery. 37 neonates (median age at start of monitoring 4 days (interquartile range 2-5 days)) were included in our study. We observed a 30% decrease in crSO2 variability between the preoperative and postoperative monitoring periods (p < 0.001). Preoperative crSO2 variability increased by 9% (p = 0.009) for each additional postnatal day. There were no associations between the degree of decrease in crSO2 variability postoperatively and class of cardiac lesion (e.g., aortic arch obstruction, single ventricle physiology) or short-term postoperative clinical outcomes. There was a significant decrease in postoperative crSO2 variability following neonatal cardiac surgery as compared to the preoperative period, likely influenced by several factors. The impact of interventions on crSO2 variability and resultant influence on long-term outcomes, such as neurodevelopmental outcomes, requires further exploration.

Early Vital Sign Differences in Very Low Birth Weight Infants with Severe Intraventricular Hemorrhage.

OBJECTIVE: Severe intraventricular hemorrhage (sIVH, grades 3 and 4) is a serious complication for very low birth weight (VLBW) infants and is often clinically silent requiring screening cranial ultrasound (cUS) for detection. Abnormal vital sign (VS) patterns might serve as biomarkers to identify risk or occurrence of sIVH. STUDY DESIGN: This retrospective study was conducted in VLBW infants admitted to two level-IV neonatal intensive care units (NICUs) between January 2009 and December 2018. Inclusion criteria were: birth weight <1.5 kg and gestational age (GA) <32 weeks, at least 12 hours of systemic oxygen saturation from pulse oximetry (SpO2) data over the first 24 hours and cUS imaging. Infants were categorized as early sIVH (sIVH identified in the first 48 hours), late sIVH (sIVH identified after 48 hours and normal imaging in the first 48 hours), and no IVH. Infants with grades 1 and 2 or unknown timing IVH were excluded. Mean heart rate (HR), SpO2, mean arterial blood pressure (MABP), number of episodes of bradycardia (HR < 100 bpm), and desaturation (SpO2 < 80%) were compared. RESULTS: A total of 639 infants (mean: 27 weeks' gestation) were included (567 no IVH, 34 early sIVH, and 37 late sIVH). In the first 48 hours, those with sIVH had significantly higher HR compared with those with no IVH. Infants with sIVH also had lower mean SpO2 and MABP and more desaturations <80%. No significant differences in VS patterns were identified in early versus late sIVH. Logistic regression identified higher HR and greater number of desaturations <80% as independently associated with sIVH. CONCLUSION: VLBW infants who develop sIVH demonstrate VS differences with significantly lower SpO2 and higher mean HR over the first 48 hours after birth compared with VLBW infants with no IVH. Abnormalities in early VS patterns may be a useful biomarker for sIVH. Whether VS abnormalities predict or simply reflect sIVH remains to be determined. KEY POINTS: · A higher HR in the first 48 hours is seen in infants with severe IVH.. · Infants with sIVH have lower blood pressure in the first 48 hours.. · Infants with sIVH have more oxygen desaturations in the first 48 hours..

Low Variability of Blood Pressure Predicts Abnormal Electroencephalogram in Infants with Hypoxic Ischemic Encephalopathy.

OBJECTIVE: This study aimed to evaluate the role of an objective physiologic biomarker, arterial blood pressure variability, for the early identification of adverse short-term electroencephalogram (EEG) outcomes in infants with hypoxic-ischemic encephalopathy (HIE). STUDY DESIGN: In this multicenter observational study, we analyzed blood pressure of infants meeting these criteria: (1) neonatal encephalopathy determined by modified Sarnat exam, (2) continuous mean arterial blood pressure (MABP) data between 18 and 27 hours after birth, and (3) continuous EEG performed for at least 48 hours. Adverse outcome was defined as moderate-severe grade EEG at 48 hours. Standardized signal preprocessing was used; the power spectral density was computed without interpolation. Multivariate binary logistic regression was used to identify which MABP time and frequency domain metrics provided improved predictive power for adverse outcomes compared with standard clinical predictors (5-minute Apgar score and cord pH) using receiver operator characteristic analysis. RESULTS: Ninety-one infants met inclusion criteria. The mean gestational age was 38.4 ± 1.8 weeks, the mean birth weight was 3,260 ± 591 g, 52/91 (57%) of infants were males, the mean cord pH was 6.95 ± 0.21, and 10/91 (11%) of infants died. At 48 hours, 58% of infants had normal or mildly abnormal EEG background and 42% had moderate or severe EEG backgrounds. Clinical predictor variables (10-minute Apgar score, Sarnat stage, and cord pH) were modestly predictive of 48 hours EEG outcome with area under curve (AUC) of 0.66 to 0.68. A composite model of clinical and optimal time- and frequency-domain blood pressure variability had a substantially improved AUC of 0.86. CONCLUSION: Time- and frequency-domain blood pressure variability biomarkers offer a substantial improvement in prediction of later adverse EEG outcomes over perinatal clinical variables in a two-center cohort of infants with HIE. KEY POINTS: · Early outcome prediction in HIE is suboptimal.. · Patterns in blood pressure physiology may be predictive of short-term outcomes.. · Early time- and frequency-domain measures of blood pressure variability predict short-term EEG outcomes in HIE infants better than perinatal factors alone..

Framework for Considering Abnormal Heart Rate Characteristics and Other Signs of Sepsis in Very Low Birth Weight Infants.

OBJECTIVE: A heart rate characteristics index (HeRO score), incorporating low variability and superimposed decelerations, was developed as a sepsis risk indicator for preterm infants in the neonatal intensive care unit (NICU). A rise in the risk score should prompt consideration of other clinical changes that may be signs of sepsis to decide whether a workup and antibiotics are needed. We aimed to develop a framework to systematically consider signs potentially indicating sepsis in very low birth weight (VLBW) infants. STUDY DESIGN: We developed easy-recall acronyms for 10 signs of sepsis in VLBW infants. Over 12 months in a level IV NICU, neonatology fellows completed a brief survey after each shift to document changes prompting sepsis workups. We analyzed associations between survey data, hourly heart rate characteristic data, and the diagnosis of the workup, grouped as culture-positive sepsis (CXSEP, positive blood or urine culture), clinical sepsis (CLINSEP, negative cultures treated with antibiotics ≥5 days), or sepsis ruled out (SRO, negative cultures and <3 days antibiotics). RESULTS: We analyzed 93 sepsis workups in 48 VLBW infants (35 CXSEP, 20 CLINSEP, and 38 SRO). The most frequently cited changes prompting the workups were heart rate patterns and respiratory deterioration, which were common in all three categories. Low blood pressure and poor perfusion were uncommonly cited but were more likely to be associated with CXSEP than the other signs. A rise in the HeRO score ≥1 from 0 to 12 hours before compared with 12to 72 hours prior the blood culture occurred in 31% of workups diagnosed as CXSEP, 16% CLINSEP, and 31% SRO. CONCLUSION: The HeRO score can alert clinicians to VLBW infants at high or increasing risk of a sepsis-like illness, but heart rate characteristic patterns are highly variable in individual babies. The easy-recall NeoSEP-10 framework can assist clinicians in considering other clinical changes when making decisions about sepsis workups and the duration of antibiotics. KEY POINTS: · Abnormal heart rate characteristics can indicate sepsis or other pathologies in preterm infants.. · We developed a simple bedside tool to consider clinical signs potentially associated with sepsis.. · Considering vital sign trends together with clinical changes is a key to right-timing antibiotics..

Primary cutaneous mucormycosis in a premature neonate treated conservatively with amphotericin B.

Cutaneous mucormycosis is a rare, often fatal fungal infection that most commonly affects patients with underlying immunosuppression but also can occur in premature neonates. We report the case of an extremely premature boy (<25 weeks) who developed primary cutaneous mucormycosis shortly after birth. Although surgical debridement has been a mainstay of treatment in combination with antifungal therapy, our patient was successfully treated with amphotericin B alone-the management only reported in three other cases to date. We present this case to highlight that prompt initiation of treatment with amphotericin B alone may be an appropriate alternative to surgical intervention, particularly in patients with non-angioinvasive disease who are poor surgical candidates.

Blood Pressure Profiles in Infants With Hypoxic Ischemic Encephalopathy (HIE), Response to Dopamine, and Association With Brain Injury.

Objective: To describe mean arterial blood pressure (MABP), responsiveness to dopamine, and relationship to brain injury in infants with moderate/severe hypoxic-ischemic encephalopathy (HIE) undergoing therapeutic hypothermia (TH). We hypothesized that, when utilized, dopamine would rapidly and effectively increase MABP in treated patients. Methods: Continuous arterial blood pressure measurements were prospectively recorded from infants with moderate/severe HIE undergoing TH in a multi-institutional cohort from 2010 to 2018. Treatment with dopamine was at the discretion of the medical team for hypotension/hypoperfusion. MABP values of treated infants were compared to those obtained at an equivalent time period in control infants receiving TH but not dopamine (24 h after birth). MRI was obtained per unit protocols and included T1/T2/DWI sequences. Injury was classified as no injury/mild injury or moderate/severe injury using a standardized scoring system. Seizures were confirmed with conventional EEG. Results: Eighteen infants were treated with dopamine and were similar to untreated controls (n = 36) with the exception of lower cord gas pH (6.92 ± 0.2 vs. 7.07 ± 0.2, p < 0.05). Dopamine was initiated at a mean of 24 h after birth. MABP was significantly lower in the dopamine group at the start of therapy (39.9 ± 2.0 vs. 49.1 ± 1.3, p < 0.01) and 1 h later (44.3 ± 2.0 vs. 49.8 ± 1.1, p < 0.05). However, after 9 h of treatment, dopamine increased the MABP by an average of 9 mmHg and MABP values were similar to untreated controls for the remainder of the observation period. There were no significant differences in rates of seizures, brain injury, or death. Conclusion: Neonates with moderate/severe HIE treated with dopamine during TH had MABP significantly lower than controls. The majority of infants responded to dopamine monotherapy following adequate volume resuscitation. An association between requirement for dopamine and severity of brain injury was not detected.

Blood pressure extremes and severe IVH in preterm infants.

BACKGROUND: The optimal upper and lower limits of blood pressure in preterm infants are not known. Exceeding these thresholds may contribute to intraventricular hemorrhage (IVH). METHODS: Preterm infants born ≤30 weeks GA were identified. Infants had continuous measurement of mean arterial blood pressure (MABP) for 7 days and cranial ultrasound imaging. IVH was classified as severe IVH (grade 3/4), no severe IVH (no IVH; grade 1/2), or no IVH. Mean ± SEM MABP values from hours 1-168 were calculated and sorted into bins 2 mm Hg wide. The normalized proportion of each recording spent in each bin was then calculated. Candidate limits were identified by comparison of MABP distribution in those with severe IVH vs. those without severe IVH. RESULTS: Eighty-five million measurements were made from 157 infants. Mean EGA was 25.2 weeks; mean BW was 749 g; 65/157 female; inotrope use in 59/157; grade 3/4 IVH in 29/157. Infants with severe IVH spent significantly more time with extreme MABP measurements (<23 mm Hg or >46 mm Hg) compared to those without severe IVH (12% vs. 8% of recording, p = 0.02). CONCLUSIONS: Infants who developed severe IVH had substantially more unstable MABP and spent a significantly greater period of time with MABP outside of the optimal range.