202501011912
Status:
Tags: Obstetrics
Cervical cerclage
Cervical insufficiency is defined as the inability of the uterine cervix to retain a pregnancy in the second trimester
ACOG: cervical cerclage should be limited to pregnancies in the second trimester before the fetus is viable
RCOG: cerclage indicated by
- patient's history : placed at 11–14 weeks of gestation
- physical examination : at up to 27+6 weeks
- ultrasound : at 14–24 weeks
typically a day-case or ambulatory procedure
Even when spinal anaesthesia is used, long-acting intrathecal opioids are generally not used
General anaesthesia affords a relatively shorter postoperative recovery period and time to discharge, yet it is associated with higher requirements for analgesia in the recovery room than regional techniques
fetal heart rate should be assessed both before and after the procedure, regardless of anaesthetic technique
continuous fetal heart rate monitoring is generally not performed during cervical cerclage placement, as the fetus is non-viable in most cases and interpretation of the fetal heart rate tracing at these gestational ages is problematic
Fetal heart rate monitoring is feasible at 18 weeks but may be technically difficult prior to 22 weeks
GA
When cervical dilation with bulging membranes is present, general anaesthesia using volatile anaesthetic agents relaxes uterine smooth muscle during cerclage placement, which can also be achieved with nitroglycerine (glyceryl trinitrate) i.v. if needed when regional anaesthesia is used
Transabdominal cerclage is usually performed using a laparoscopic surgical approach, thereby requiring general anaesthesia with tracheal intubation. If, however, performed as an open procedure, neuraxial anaesthesia is an option.
Intraoperative management should focus on avoiding hypoxemia, hypotension, acidosis, and hyperventilation, which are the most critical elements of anesthetic management
RA
avoid GA / intubation
↓ fetal exposure to anaesthetic agents
SA vs CSE
The doses reported in the literature to achieve adequate dermatomal coverage are
- ropivacaine 6.9–7.8 mg
- chloroprocaine 45–50 mg
- hyperbaric bupivacaine 7.5–9 mg
addition of intrathecal fentanyl (10–15 μg) to the local anaesthetic also improves the quality and increases the duration of sensory block
| Local anaesthetic | Suggested dose (mg) | Advantages | Disadvantages |
|---|---|---|---|
| Hyperbaric bupivacaine | 7.5–9 | - Long history of safe use in obstetric patients - Provides dense sensory block - Ability to control or change block height with patient's position |
- Long duration of action - Prolonged motor block - Delayed hospital discharge |
| Chloroprocaine | 54–60 | - Provides effective anaesthesia for cervical cerclage - Shorter time to sensory block resolution (at doses studied), leading to earlier discharge after the procedure - Faster resolution of sensory block |
- Limited experience in obstetric patients - Doses higher than 50 mg have not been well studied |
| Ropivacaine | 8–9 | - Medium duration of action - Less motor block than hyperbaric bupivacaine |
- Limited data available for cervical cerclage |
Although time to recovery after the procedure is longer when regional anaesthesia is used, there are overwhelming benefits:
- excellent analgesia,
- decreased fetal exposure to general anaesthetic agents,
- improved postoperative pain control compared with general anaesthesia
Sensory blockade is needed from sacral to T10 dermatome to cover:
- the cervix (T10 to L1)
- vagina and perineum (S2 to S4)