Visual Estimation of Force Applied During Simulated Deliveries Complicated by Shoulder Dystocia

Background  Shoulder dystocia occurs when the fetal head delivers, but the shoulder is lodged behind the pubic symphysis. Training for these emergency deliveries is not optimized, and litigation can occur around a shoulder dystocia delivery. Objective  Evaluate the ability of an outside observer to visually estimate the amount of traction applied to the fetal head during simulated deliveries complicated by shoulder dystocia. Study Design  Simulated deliveries with an objective measurement of traction were randomly organized for estimation of traction applied. Videos show providers applying a "normal" (75 N) and "excessive" (150 N) amount of force in both a "calm" and "stressed" delivery. Results  Fifty participants rated the amount of force applied. Observers estimated traction, on a scale from 1 to 5, higher in the 150-N deliveries as compared with 75-N deliveries ("calm" environment: 3.1 vs. 2.8, p  < 0.001; and "stressed" environment: 3.2 vs. 2.8, p  < 0.001). Only 15% of observers rated force "above average" or "excessive" in a "calm" environment, as opposed to 30% of observers in the "stressed" environment. Conclusion  Observers are not able to determine when "excessive force" is used and are twice as likely to overestimate the force applied to a fetal head when an average amount of force is used and the delivery environment is stressful. Precis  Observers are unable to determine when excessive traction is applied to the fetal head during simulated deliveries complicated by shoulder dystocia.