Experience in the implementation of the early warning sign system in obstetric patients (Maternal Early Warning Criteria, MEWC) during early postpartum. A prospective observational study

Objective To evaluate the implementation of an early warning system in obstetric patients (MEWC) during the first two hours after delivery in a single tertiary-care hospital. Methods The MEWC system implementation was carried out from 15th March to 15th September 2018, over 1166 patients. The parameters collected were systolic and diastolic blood pressure, heart rate, oxygen saturation, diuresis, uterine involution, and bleeding. If a parameter was not within defined limits, an obstetrician first examined the patient, determining the need to call the anesthesiologist. We carried out a sensitivity-specificity study of the trigger and multivariate analysis of the factors involved in developing potentially fatal disorders (PFD), reintervention, critical care admission, and stay. Results The protocol was triggered in 75 patients (6.43%). The leading cause of alarm activation was the altered systolic blood pressure (32 [42.7%] patients), and eleven developed PFD. Twenty-eight patients were false-negatives. Sensitivity and specificity of MEWC protocol were 0.28 (0.15, 0.45) and 0.94 (0.93, 0.96), respectively. Multivariate analysis showed a relationship between alarm activation and PFD. Conclusion Our MEWC protocol presented low sensitivity and high specificity, having a significant number of false-negative patients. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement no external funding was received. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethic Research Comittee at Hospital Fundacion Jimenez Diaz approved on the 24th October 2017 All necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All data has been self collected during fieldwork and is available for review if needed.