Reliability of ultrasound findings acquired with handheld apparatuses to inform urgent obstetric diagnosis in a high-volume resource-limited setting

Objective: To evaluate the reliability of obstetric handheld smartphone-based point-of-care ultrasound (POCUS) in a resource-limited high-volume setting. Methods: A single-center prospective observational study among women requiring urgent diagnosis and admitted to a maternity referral hospital in Sierra Leone from March to April 2019. Pre-specified ultrasound findings were obtained with a handheld POCUS device; a comprehensive ultrasound examination was then performed by an experienced operator using conventional full-feature apparatus. Agreement was assessed by diagnostic accuracy and Cohen κ-statistics. Results: Overall, there were 307 participants. The mean aggregated diagnostic accuracy was 95.5% (κ-statistic, 0.90; 95% confidence interval [CI], 0.89–0.93; P < 0.001). Highest accuracy was reported for detecting free fluid collection in the abdominal cavity (100%; κ-statistic, 1.00; 95% CI, 1.00–1.00; P < 0.001). Ultrasound findings obtained with the handheld device for intrauterine pregnancy, fetal heartbeat, cephalic presentation, multifetal pregnancy, and assessment of gestational age based on bi-parietal diameter were highly reliable (agreement, >90%; κ-statistic, >0.80). Detection of low-lying placenta or placenta previa was the least reliable (κ-statistic, 0.53; 95% CI, 0.13–0.93; P < 0.001). Conclusion: Handheld POCUS findings were found to be reliable for detecting pre-specified urgent obstetric findings in a high-volume resource-limited referral hospital.