A description of pregnant women with organophosphate poisoning at Chris Hani Baragwanath academic hospital

Abstract

Background: Organophosphate poisoning (OPP) is of public health importance as it poses a significant health risk that is associated with a high case fatality. Its severity in pregnancy is unknown due to limited studies.

Objective: To describe the socio-demographic characteristics, clinical features, maternal, fetal and early neonatal outcomes in pregnant women presenting with OPP at Chris Hani Baragwanath Academic Hospital (CHBAH), South Africa (SA).

Method: This was a retrospective descriptive study that reviewed 30 medical records of pregnant women who presented with OPP at CHBAH from 1st of January 2017 to 31st December 2019. Descriptive analyses were conducted. Fisher’s exact test was used to explore the association between potential risk factors and maternal, fetal, and early neonatal outcomes. A p-value of ≤0.05 was statistically significant.

Results: Most women with OPP were between 18 - 35 years (n = 25; 83.3%), unemployed (n = 22; 73.3%), single (n = 26; 86.7%), and of the African race (n = 29; 96.7%). Eighty percent of these cases (n = 24) were intentional ingestion whilst one (3.3%) was accidental exposure. Majority were booked (n = 21; 70.0%), HIV negative (n = 27; 93.3%), rhesus positive (n = 29; 96.3%), rapid plasma reagin negative (100 %) with a median booking haemoglobin of 10.4g/dl (IQR 10.1 - 12.1, range 9.1 - 13.4) and median gestational age of 21 (IQR 18 - 24, range 16 - 34) weeks at booking and 30 (IQR 27 - 34, range 14 - 37) weeks on admission. There were 24 (81.2%) patients who were acidotic, with the worst median lactate of 2.85 (IQR 2.1 - 4.1, range 0.6 - 18.7) and worst median pH of 7.30 (IQR 7.21 - 7.30, range 6.9 - 7.52). The maternal fatality rate was 10% (n = 3) and half (n = 15; 50.0%) required ventilation, with median duration of ventilation being four days(IQR 1-3, range 1-19). All the women had delivered with 13 (43.3%) live births, four (13.3%) miscarriages, and 13 (43.3%) stillbirths. A loading dose of atropine >9.0mg was significantly associated with maternal death (p-value = 0.04). Poor fetal outcomes and early neonatal deaths were associated with unbooked status (p-value = 0.01), maternal pH ≤7.35 (p-value = 0.02), maternal ventilation (p-value = 0.01), maternal admission longer than 6.5 days in hospital (p-value = 0.02), maternal GCS ≤14 (p-value = 0.05).

Conclusion: Organophosphate poisoning in pregnancy is associated with significant morbidity and mortality in pregnant women and poor pregnancy outcomes.