A primigravida at full dilation has a vertex in deep transverse arrest at +2 station. Rotation is planned with forceps. Which instrument feature distinguishes Kielland's forceps and makes it suitable for this task?
- A English lock with overlapping shanks and axis traction handles
- B Sliding lock allowing asymmetric blade application and correction of asynclitism ✓
- C Fenestrated blades designed for the aftercoming head of a breech
- D Wandering blades applied one above the other for face presentation
Correct answer: B. Sliding lock allowing asymmetric blade application and correction of asynclitism
Explanation
Kielland's forceps have a sliding lock, minimal pelvic curvature, and light weight, allowing the blades to be applied asymmetrically around an unmoulded head, correct asynclitism, and rotate the vertex from occiput transverse to occiput anterior in deep transverse arrest. Wrigley's and outlet forceps lack a sliding lock and cannot safely perform mid-cavity rotation.
Reference: Williams Obstetrics, 26th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.