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Comparing forces on the fetal neck in breech delivery in lithotomy versus all-fours position: a simulation model
Delnaz Fard1, Chiara S Borchers1, Jill-Caren Philippeit1
1Department of Obstetrics, Gynecology and Reproductive Medicine, Hanover Medical School, Carl-Neuberg-Str. 1, 30625, Hanover, Germany.
Purpose:
To measure forces applied to the fetal neck, in a simulation model for breech delivery, in both lithotomy versus all-fours position.
Methods:
We used a Laerdal SimMom simulator and a Birthing Baby together with PROMPT Flex Software. The descent of the fetus was accomplished using the Automatic Delivery Module 2. The baby was always in breech position; the SimMom in either all-fours or lithotomy positions. Sensors were located inside the fetal neck region to simulate forces applied to the plexus.
Results:
The lowest force on the fetal neck region was recorded for the delivery in all-fours position without further maneuvers (mean force 58.70 Newton, standard deviation 2.54 N). As weight was added to the baby, the force increased (i.e. + 500 g, mean force 71.8 N, SD 3.08 N, p < 0.001). Delivery in lithotomy position resulted in a mean force of 81.56 N (SD 19.55 N). The force significantly increased in case of delivery of the head without assistance from contractions (mean force 127.93 N, SD 23.10 N). In all-fours position, the delivery of the fetal head from pelvic floor level without contractions (Frank's Nudge maneuver) resulted in a mean force of 118.45 N (SD 15.48 N, p = 0.02). Maneuvers for shoulder dystocia (the inverted type that can occur during breech delivery) led to significantly higher mean forces independent from birthing positions.
Conclusion:
Breech delivery in all-fours position was associated with the lowest force acting on the fetal neck in our simulation model.
