Routine Bedside Use of Obstetric Early Warning System in the Postnatal Ward to Identify Maternal Morbidity Among High-Risk Women.

OBJECTIVE: Several authorities have recommended the use of an obstetric early warning system (OEWS) to prevent severe morbidity and mortality. Data on the accuracy of OEWS in different clinical settings and maternal populations are still scarce. Our aim was to validate OEWS to detect maternal morbidity among high-risk women in the postnatal ward. METHODS: An OEWS was assigned to women with a body mass index >35 kg/m2, postpartum hemorrhage (PPH) >1500 mL, preeclampsia, concern over the maternal condition, chorioamnionitis, or type 1 diabetes. Morbidity was defined as worsening preeclampsia, action on hemorrhage, thromboembolia, diabetic ketoacidosis, puerperal infections, transfer to the intensive care unit, cardiopulmonary dysfunction, or death during the stay in the postnatal ward. The use of OEWS was implemented on November 1, 2016, and the study period ended on April 30, 2018. RESULTS: The study group included 827 women. The incidence of maternal morbidity was 29%. Women with PPH (odds ratio [OR], 6.4 [95% confidence interval, 3.5-11.6]) and preeclampsia (OR, 5.7 [3.5-9.6]) had the highest risk for morbidity. The sensitivity of OEWS for any morbidity was 42% (35%-48%), the specificity was 83% (80%-86%), the positive predictive value was 50% (44%-56%), and the negative predictive value was 78% (76%-80%). Systolic (OR, 6.8 [4.0-11.5]) and diastolic (OR, 3.3 [1.8-6.0]) blood pressure as well as pulse (OR, 2.1 [1.1-4.2]) predicted morbidity the most. CONCLUSIONS: In high-risk women, OEWS revealed one-half of the morbidity. Women with PPH and preeclampsia benefited most from it. Abnormal blood pressure and pulse had the strongest associations with morbidity.

Obstetric early warning system to predict maternal morbidity of pre-eclampsia, postpartum hemorrhage and infection after birth in high-risk women: a prospective cohort study.

OBJECTIVE: The purpose of early warning systems is to detect deterioration of the patient and to enable timely intervention to prevent possible severe illness. The most common causes of maternal morbidity and mortality after birth are worsening pre-eclampsia, postpartum haemorrhage and puerperal infection. Our aim was to validate the accuracy of the obstetric early warning system and different physiological triggers to predict morbidity on the postnatal ward in high-risk women. DESIGN: A prospective cohort study. SETTING: A tertiary referral hospital in Finland. PARTICIPANTS: High-risk women (n=828) (body mass index > 35 kg/m2, postpartum haemorrhage > 1,500 g, pre-eclampsia, chorioamnionitis during birth, type 1 diabetes or anxiety over the maternal condition based on clinical judgement) were studied on the postnatal ward in the first 24 hours after giving birth. In this study population the women without any morbidity served as a control group. The study was conducted between 1.11.2016 - 30.4. 2018 covering a period of 18 months. MEASUREMENTS AND FINDINGS: The accuracy of the obstetric early warning system and its five physiological parameters-respiratory rate, oxygen saturation, blood pressure, heart rate and body temperature-and a pain score to predict worsening pre-eclampsia, complications related to postpartum haemorrhage and puerperal infection were determined. A red trigger is as a single, markedly abnormal observation, and a yellow trigger is a combination of two mildly abnormal observations. The sensitivity of obstetric early warning system at its best was 72% for pre-eclampsia, 52% for infection and 25% for postpartum haemorrhage. The red triggers were significantly associated with morbidity in each outcome studied. The red triggers of systolic blood pressure (OR 25.7, 95% CI 13.2-50.1) and diastolic blood pressure (OR 22.1, 95% CI 11.3-43.0) were independently associated with pre-eclampsia, systolic blood pressure (OR 2.7, 95% CI 1.4-5.6) and heart rate (OR 3.6, 95% CI 1.7-7.6) with postpartum haemorrhage and heart rate (OR 3.3, 1.0-10.3) with infection. KEYCONCLUSIONS: The sensitivity of obstetric early warning system varied depending on the type of morbidity. The highest sensitivity and positive predictive value were in pre-eclampsia. Systolic and diastolic blood pressure and heart rate were the strongest physiological parameters to predict morbidity. IMPLICATIONS FOR PRACTICE: The systematic use of obstetric early warning system helps to improve maternal safety after birth in high-risk women. Blood pressure and pulse are the most important measurements.