Performance of the INTERGROWTH-21st and World Health Organization fetal growth charts for the detection of small-for-gestational age neonates in Latin America

OBJECTIVE

To evaluate the performance of INTERGROWTH-21^st (IG-21^st ) and World Health Organization (WHO) fetal growth charts to identify small-for-gestational-age (SGA) and fetal growth restriction (FGR) neonates, as well as their specific risks for adverse neonatal outcomes.

METHODS

Multicenter cross-sectional study including 67 968 live births from 10 maternity units across four Latin American countries. According to each standard, neonates were classified as SGA and FGR (birth weight <10^th and less than third centiles, respectively). The relative risk (RR) and diagnostic performance for a low APGAR score and low ponderal index were calculated for each standard.

RESULTS

WHO charts identified more neonates as SGA than IG-21^st (13.9% vs 7%, respectively). Neonates classified as having FGR by both standards had the highest RR for a low APGAR (RR, 5.57 [95% confidence interval (CI), 3.99-7.78]), followed by those who were SGA by both curves (RR, 3.27 [95% CI, 2.52-4.24]), while neonates with SGA identified by WHO alone did not have an additional risk (RR, 0.87 [95% CI, 0.55-1.39]). Furthermore, the diagnostic odds ratio for a low APGAR was higher when IG-21^st was used.

CONCLUSION

In a population from Latin America, the WHO charts seem to identify more SGA neonates, but the diagnostic performance of the IG-21^st charts for low APGAR score and low ponderal index is better.

Performance of the Obstetric Early Warning Score in critically ill patients for the prediction of maternal death

BACKGROUND

Every day, about 830 women die worldwide from preventable causes related to pregnancy and childbirth. Obstetric early warning scores have been proposed as a potential tool to reduce maternal morbidity and mortality, based on the identification of predetermined abnormal values in the vital signs or laboratory parameters, to generate a rapid and effective medical response. Several early warning scores have been developed for obstetrical patients, but the majority are the result of a clinical consensus rather than statistical analyses of clinical outcome measures (ie, maternal deaths). In 2013, the Intensive Care National Audit and Research Center Case Mix Program reported the first statistically validated early warning scoring system for pregnant women.

OBJECTIVE

We sought to assess the performance of the Intensive Care National Audit and Research Center Obstetric Early Warning Score in predicting death among pregnant women who required admission to the intensive care unit.

STUDY DESIGN

This retrospective cohort study included pregnant women admitted to the intensive care unit at a tertiary referral center from January 2006 through December 2011 in Colombia, a developing country, with direct and indirect obstetric-related conditions. The Obstetric Early Warning Score was calculated based on data collected during the first 24 hours of intensive care unit admission. The Obstetric Early Warning Score is calculated based on values of the following variables: systolic and diastolic blood pressure, respiratory rate, heart rate, fraction of inspired oxygen (FiO₂) required to maintain an oxygen saturation ≥96%, temperature, and level of consciousness. The performance of the Obstetric Early Warning Score was evaluated using the area under the receiver operator characteristic curve. Outcomes selected were: maternal death, need for mechanical ventilation, and/or vasoactive support. Statistical methods included distribution appropriate univariate analyses and multivariate logistic regression.

RESULTS

During the study period, 50,897 births were recorded. There were 724 obstetric admissions to critical care, for an intensive care unit admission rate of 14.22 per 1000 deliveries. A total of 702 women were included in the study, with 29 (4.1%) maternal deaths, and a mortality ratio of 56.98 deaths per 100,000 live births. The most frequent causes of admission were direct, obstetric-related conditions (n = 534; 76.1%). The Obstetric Early Warning Score value was significantly higher in nonsurvivors than in survivors [12 (interquartile range 10-13) vs 7 (interquartile range 4-9); P < .001]. Peripartum women with normal values of Obstetric Early Warning Score had 0% mortality rate, while those with high Obstetric Early Warning Score values (>6) had a mortality rate of 6.3%. The area under the receiver operator characteristic curve of the Obstetric Early Warning Score in discrimination of maternal death was 0.84 (95% confidence interval, 0.75-0.92). The overall predictive value of the Obstetric Early Warning Score was better when the main cause of admission was directly related to pregnancy or the postpartum state. The area under the receiver operator characteristic curve of the score in conditions directly related to pregnancy and postpartum was 0.87 (95% confidence interval, 0.79-0.95), while in indirectly related conditions the area under the receiver operator characteristic curve was 0.77 (95% confidence interval, 0.58-0.96).

CONCLUSION

Although there are opportunities for improvement, Obstetric Early Warning Score obtained upon admission to the intensive care unit can predict survival in conditions directly related to pregnancy and postpartum. The use of early warning scores in obstetrics may be a highly useful approach in the early identification of women at an increased risk of dying.

The impact of Advanced Life Support in Obstetrics (ALSO) training in low-resource countries

OBJECTIVE

To examine the effects of the Advanced Life Support in Obstetrics (ALSO) program on maternal outcomes in four low-income countries.

METHODS

Data were obtained from single-center, longitudinal cohort studies in Colombia, Guatemala, and Honduras, and from an uncontrolled prospective trial in Tanzania.

RESULTS

In Colombia, maternal morbidity and the number of near misses increased after ALSO training, but maternal mortality decreased. In Guatemala, sustained reductions in overall maternal mortality and mortality from postpartum hemorrhage (PPH) were recorded after ALSO implementation. In Honduras, there was a significant decrease in episiotomy rates, and increases in active management of the third stage of labor (AMTSL), vacuum-assisted delivery, and reported comfort managing obstetric emergencies. In Tanzania, the frequency of PPH and severe PPH decreased after training, while management improved.

CONCLUSION

In low-income countries, ALSO training was associated with decreased in-hospital maternal mortality, episiotomy use, and PPH. AMTSL and vacuum-assisted vaginal delivery increased in frequency after ALSO training.

Mechanical ventilation in critically-ill pregnant women: a case series

BACKGROUND

Approximately 0.1-0.2% of pregnancies are complicated by respiratory failure requiring mechanical ventilatory support, but few data exist to inform clinical management. This study aimed to characterize current practice and the effect of delivery on respiratory function.

METHODS

A retrospective review was performed of pregnant women who received mechanical ventilation for more than 24h, from four intensive care units in institutions with large-volume obstetric units.

RESULTS

Data were collected from 29 patients with a mean gestation at intensive care unit admission of 25.3 ± 6 weeks. Tidal volumes were 7.7 ± 1.7 mL/kg predicted body weight. Estimated respiratory system compliance was reduced, but was higher in four patients ventilated for neurological conditions without lung disease. Three maternal and three neonatal deaths occurred. Ten patients delivered while on ventilatory support: one spontaneous delivery, four for obstetric indications and five for worsening maternal condition. Following delivery of these 10 patients, three demonstrated a greater than 50% decrease in oxygenation index and five a greater than 50% increase in compliance. No characteristics identified which patients may benefit from delivery.

CONCLUSIONS

Review of current practice in four centers suggests that mechanical ventilation in pregnant patients follows usual guidelines applicable to non-pregnant patients. Delivery was associated with modest improvement in maternal respiratory function in some patients. Any potential benefit of delivery in improving maternal physiology must be weighed against the stress of delivery. The risks of premature birth for the fetus must be weighed against continued exposure to maternal hypoxemia and hypotension.

Mortality risk prediction with an updated Acute Physiology and Chronic Health Evaluation II score in critically ill obstetric patients: a cohort study

BACKGROUND

Acute Physiology and Chronic Health Evaluation II (APACHE II) score has shown low prognostic ability to predict death in the obstetric population. The objective of this study was to evaluate whether an updated form of the APACHE II score would perform better in predicting mortality in critically ill obstetric patients.

METHODS

A retrospective cohort study of pregnant and postpartum women (up to 42 days after delivery) who were admitted to the intensive care unit (ICU) was carried out at an ICU at Rafael Calvo Maternity Hospital, a large obstetric hospital in Colombia. Data were collected on consecutive obstetric patients admitted to the ICU between 2006 and 2011. A discrimination and calibration analysis was completed on the original APACHE II score and an updated APACHE II score.

RESULTS

Data were collected on a total of 726 obstetric patients. The area under the receiver-operating characteristic curve was 0.86 (95% confidence interval [95% CI], 0.80-0.93) for both APACHE II and the updated APACHE II scores. Mortality ratio for the original APACHE II was 0.30 (95% CI, 0.19-0.41) and 0.85 (95% CI, 0.56-1.24) for the updated APACHE II.

CONCLUSIONS

The APACHE II overestimates mortality in the sample population. The updated APACHE II model predicts mortality more accurately in the obstetric population. This formula may be useful in adapting the existing APACHE II to current mortality risk in obstetric critical care populations.