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A Spine Robotic-Assisted Navigation System for Pedicle Screw Placement
Published on: May 11, 2020
Risk factors and morbidity associated with suboptimal instrument placement at instrumental delivery: observational
M Ramphul1, M M Kennelly, G Burke
1Department of Obstetrics and Gynaecology, Trinity College Dublin, Coombe Women and Infants University Hospital, Dublin, Ireland.
Objectives:
To identify risk factors and morbidity associated with suboptimal instrument placement at instrumental delivery.
Design:
Observational study, nested within a randomised controlled trial.
Setting:
Two university-affiliated maternity hospitals.
Sample:
A cohort of 478 nulliparous women at term (≥37 weeks of gestation) undergoing instrumental delivery.
Methods:
Univariable and multivariable logistic regression analyses were performed.
Main Outcome Measures:
Risk factors for suboptimal application of vacuum or forceps, maternal and neonatal morbidity, and the sequential use of instruments, second operator, and caesarean section following failed instrumental delivery.
Results:
Instrument placement was suboptimal in 138 of 478 (28.8%) deliveries. Factors associated with suboptimal instrument placement included fetal malposition (OR 2.44, 95% CI 1.62-3.66), mid-cavity station (OR 1.68, 95% CI 1.02-2.78), and forceps as the primary instrument (OR 2.01, 95% CI 1.33-3.04). Compared with optimal instrument placement, suboptimal placement was associated with prolonged hospital stay (adjusted OR 2.28, 95% CI 1.30-4.02) and neonatal trauma (adjusted OR 4.25, 95% CI 1.85-9.72). Suboptimal placement was associated with a greater use of sequential instruments (adjusted OR 3.99, 95% CI 1.94-8.23) and caesarean section for failed instrumental delivery (adjusted OR 3.81, 95% CI 1.10-13.16). The mean decision to delivery interval (DDI) was 4 minutes longer in the suboptimal group (95% CI 2.1-5.9 minutes).
Conclusions:
Suboptimal instrument placement is associated with increased maternal and neonatal morbidity and procedural complications. Greater attention should be focused on instrument placement when training obstetricians for instrumental delivery.
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