Total plasma protein in very preterm babies: prognostic value and comparison with illness severity scores

Blood volume reduction due to rapid plasma loss after birth in preterm piglets

BACKGROUND

Understanding changes in blood volume after preterm birth is critical to preventing cardiovascular deterioration in preterm infants. The aims were to determine if blood volume is higher in preterm than term piglets and if blood volume changes in the hours after birth.

METHODS

Paired blood volume measurements were conducted in preterm piglets (98/115d gestation, ~28wk gestation infant) at 0.5-5 h (n = 12), 0.5-9 h (n = 44) and 5-11 h (n = 7) after birth, and in a term cohort at 0.5-9 h (n = 40) while under intensive care.

RESULTS

At 30 min after birth, blood volume was significantly lower in preterm piglets compared to term piglets. By 9 h after birth, blood volume had reduced by 18% in preterm piglets and 13% in term piglets. By 5-9 h after birth, preterm piglets had significantly lower blood volumes than at term (61 ± 10 vs. 76 ± 11 mL/kg).

CONCLUSIONS

In contrast to clinical resources, preterm piglets have a lower blood volume than at term. Substantial reductions in blood volume after birth leave some preterm piglets hypovolemic. If this also occurs in preterm infants, this may have important clinical consequences. Modern studies of blood volume changes after birth are essential for improving preterm outcomes.

IMPACT

Preterm piglets do not have a higher blood volume than their term counterparts, in contrast to current clinical estimates. Rapid reduction in blood volume after birth leads to hypovolemia in some preterm piglets. There is a critical need to understand blood volume changes after birth in preterm infants in order to improve clinical management of blood volume.

Low albumin levels are independently associated with neonatal acute kidney injury: a report from AWAKEN Study Group

BACKGROUND

Data from adult and pediatric literature have shown an association between albumin levels and AKI. Whether hypoalbuminemia and neonatal AKI are associated has not been studied.

METHODS

We evaluated the association of albumin with early (during the first postnatal week) and late (after the first postnatal week) AKI for 531 neonates from the Assessment of Worldwide AKI Epidemiology in Neonates (AWAKEN) database and for 3 gestational age (GA) subgroups: < 29, 29 to < 36, and ≥ 36 weeks GA.

RESULTS

Low albumin levels were associated with increased odds of neonatal AKI; for every 0.1 g/dL decrease in albumin, the odds of late AKI increased by 12% on continuous analysis. After adjustment for potential confounders, neonates with albumin values in the lowest quartiles (< 2.2 g/dL) had an increased odds of early [Adjusted Odd Ratio (AdjOR) 2.5, 95% CI = 1.1-5.3, p < 0.03] and late AKI [AdjOR 13.4, 95% CI = 3.6-49.9, p < 0.0001] compared to those with albumin in the highest quartile (> 3.1 g/dL). This held true for albumin levels 2.3 to 2.6 g/dL for early [AdjOR 2.5, 95% CI = 1.2-5.5, p < 0.02] and late AKI [AdjOR 6.4, 95% CI = 1.9-21.6, p < 0.01]. Albumin quartiles of (2.7 to 3.0 g/dL) were associated with increased odds of late AKI. Albumin levels of 2.6 g/dL and 2.4 g/dL best predicted early (AUC = 0.59) and late AKI (AUC = 0.64), respectively. Analysis of albumin association with AKI by GA is described.

CONCLUSIONS

Low albumin levels are independently associated with early and late neonatal AKI. Albumin could be a potential modifiable risk factor for neonatal AKI.

Comparison of different neonatal illness severity scores in predicting mortality risk of extremely low birth weight infants

To compare different illness severity scores in predicting mortality risk of extremely low birth weight infants (ELBWI). From January 1st, 2019 to January 1st, 2020, all ELBWI admitted in the Children's Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital and the First Affiliated Hospital of Nanjing Medical University were included in the study. ELBWI with admission age ≥1 h, gestational age ≥37 weeks and incomplete data required for scoring were excluded. The clinical data were collected, neonatal critical illness score (NCIS), score for neonatal acute physiology version Ⅱ (SNAP-Ⅱ), simplified version of the score for neonatal acute physiology perinatal extension (SNAPPE-Ⅱ), clinical risk index for babies (CRIB) and CRIB-Ⅱ were calculated. The scores of the fatal group and the survival group were compared, and the receiver operating characteristic (ROC) curve was used to evaluate the predictive value of the above illness severity scores for the mortality risk of ELBWI. Pearson correlation analysis was used to analyze the correlation between illness scores and birth weight, illness scores and gestational age. A total of 192 ELBWI were finally included, of whom 114 cases survived (survival group) and 78 cases died (fatal group). There were significant differences in birth weight, gestational age and Apgar scores between fatal group and survival group (all <0.01). There were significant differences in NCIS, SNAP-Ⅱ, SNAPPE-Ⅱ, CRIB and CRIB-Ⅱ between fatal group and survival group (all <0.01). The CRIB had a relatively higher predictive value for the mortality risk. Its area under the ROC curve (AUC) was 0.787, the sensitivity was 0.678, the specificity was 0.804, and the Youden index was 0.482. The scores of NCIS, SNAP-Ⅱ, SNAPPE-Ⅱ, CRIB and CRIB-Ⅱ were significantly correlated with birth weight and gestational age (all <0.05). The correlation coefficients of CRIB-Ⅱ and CRIB with birth weight and gestational age were relatively large, and the correlations coefficients of NCIS with birth weight and gestational age were the smallest (0.191 and 0.244, respectively). Among these five illness severity scores, CRIB has better predictive value for the mortality risk in ELBWI. NCIS, which is widely used in China, has relatively lower sensitivity and specificity, and needs to be further revised.

Low Plasma Protein Levels at Birth Are Associated with Poor Cardiovascular Adaptation and Serious Adverse Outcome in Infants with Gestational Age <32 Weeks: The ProHémie Study

BACKGROUND

Retrospective studies suggest that early hypoproteinemia has prognostic value for adverse outcome in preemies, but the underlying pathophysiology is unknown. We hypothesized that the prognostic relevance of hypoproteinemia could be related to its association with impaired cardiovascular function and organ perfusion during transition.

OBJECTIVES

To describe the plasma protein status and the measures of cardiovascular function according to the outcome in infants <32 weeks' gestation.

METHODS

One hundred and twenty-eight infants were prospectively included from birth to discharge. During the first 24 h of life, we assessed the cardiovascular function and systemic and organ blood flow by Doppler ultrasound, and monitored cerebral and renal regional oxygen saturation (cRSO2, rRSO2) using near-infrared spectroscopy. These measures were analyzed in relationship to hypoproteinemia (total plasma protein level <40 g/L at 12 h of life) and severe adverse outcome (death or survival with severe neurological injury).

RESULTS

Hypoproteinemia was associated with a higher risk of a severe adverse outcome after adjustment of confounding variables (adjusted OR = 6.8; 95% CI 1.3-34). Compared to normoproteinemic infants and after adjustment for gestational age, hypoproteinemic ones had more significantly: hypotension (7 vs. 13%, p = 0.03), abnormal capillary refilling time (20 vs. 36%, p < 0.001), abnormal renal blood flow (resistive index 0.78 ± 0.11 vs. 0.85 ± 0.09, p = 0.04), lower rRSO2 (82.9 ± 9.2 vs. 73.6 ± 10.5%, p = 0.04), and lower systemic vascular resistance (0.155 ± 0.058 vs. 0.108 ± 0.037 mm Hg/L/kg; p = 0.04). The cRSO2 patterns were significantly decreased in infants with severe adverse outcome and independent from protein status.

CONCLUSION

Hypoproteinemia is associated with impaired cardiovascular function. Further studies are required to elucidate the interplay between changes in protein levels, postnatal hemodynamics and clinical outcome.

Relationship Between Serum Albumin Levels and Infections in Newborn Late Preterm Infants

Background

We aimed to evaluate the clinical value of serum albumin levels for the evaluation and prognosis of late preterm infants with infections.

Material/Methods

This was a retrospective study performed in late preterm infants admitted at the neonatal intensive care unit (NICU) of the Liaocheng People’s Hospital between July 2012 and March 2013. Data, including laboratory test results, neonatal critical illness score (NCIS), perinatal complications and prognosis, were analyzed. The newborn infants were divided into 3 groups according to their serum albumin levels, (≥30 g/L, 25–30 g/L and ≤25 g/L for high, moderate, and low, respectively).

Results

Among 257 patients, birth weight was 2003±348 g, gestational age was 35.7±2.3 weeks, and 59.1% were male. In addition, 127 (49.4%) were in the low albumin group. There were 32 patients with sepsis, 190 with infections, and 35 without infection, and their rates of hypoalbuminemia were 86.0%, 50.5%, and 30.7%, respectively (P<0.05). Albumin levels of the patients who survived were higher than those of the patients who died. In the low albumin group, the number of individual-event-critical NCIS cases and the frequency of multiple organs injuries were 63.8% and 28.3%, respectively, and were higher than in the 2 other groups. Mortality was higher in patients with sepsis. Hypoalbuminemia was associated with severe adverse outcomes (odds ratio=6.3, 95% confidence interval: 3.7–10.9, P<0.001).

Conclusions

Hypoalbuminemia was frequent among neonates with sepsis. Lower albumin levels might be associated with a poorer prognosis. Albumin levels could be appropriate for the diagnosis and prognosis of late preterm neonates with infections.

A Systematic Review: The Utility of the Revised Version of the Score for Neonatal Acute Physiology Among Critically Ill Neonates

The revised version of the Score for Neonatal Acute Physiology (SNAP-II) has been used across all birth weights and gestational ages to measure the concept of severity of illness in critically ill neonates. The SNAP-II has been operationalized in various ways across research studies. This systematic review seeks to synthesize the available research regarding the utility of this instrument, specifically on the utility of measuring severity of illness sequentially and at later time points. A systematic review was performed and identified 35 research articles that met inclusion and exclusion criteria. The majority of the studies used the SNAP-II instrument as a measure of initial severity of illness on the first day of life. Six studies utilized the SNAP-II instrument to measure severity of illness at later time points and only 2 studies utilized the instrument to prospectively measure severity of illness. Evidence to support the use of the SNAP-II at later time points and prospectively is lacking and more evidence is needed.

Interstitial fluid colloid osmotic pressure in healthy children

Objective

The colloid osmotic pressure (COP) of plasma and interstitial fluid play important roles in transvascular fluid exchange. COP values for monitoring fluid balance in healthy and sick children have not been established. This study set out to determine reference values of COP in healthy children.

Materials and Methods

COP in plasma and interstitial fluid harvested from nylon wicks was measured in 99 healthy children from 2 to 10 years of age. Nylon wicks were implanted subcutaneously in arm and leg while patients were sedated and intubated during a minor surgical procedure. COP was analyzed in a colloid osmometer designed for small fluid samples.

Results

The mean plasma COP in all children was 25.6 ± 3.3 mmHg. Arbitrary division of children in four different age groups, showed no significant difference in plasma or interstitial fluid COP values for patients less than 8 years, whereas patients of 8-10 years had significant higher COP both in plasma and interstitial fluid. There were no gender difference or correlation between COP in interstitial fluid sampled from arm and leg and no significant effect on interstitial COP of gravity. Prolonged implantation time did not affect interstitial COP.

Conclusion

Plasma and interstitial COP in healthy children are comparable to adults and COP seems to increase with age in children. Knowledge of the interaction between colloid osmotic forces can be helpful in diseases associated with fluid imbalance and may be crucial in deciding different fluid treatment options.

Trial Registration

ClinicalTrials.gov NCT01044641