Cesarean Section (Multi-Gestation)

Term multi-gestation

Summary

• Dose: 2.2-2.3 ml (11-11.5 mg) 0.5% hyperbaric bupivacaine + 15 mcg fentanyl + 100 mcg morphine

• Position: Sitting or lateral, immediately supine.

• Expectation: Surgical block for up to 90 minutes post-spinal.

Evidence

• Jawan et al. demonstrated that 10 mg 0.5% hyperbaric bupivacaine in twin pregnancies achieved a higher sensory level to pinprick (T3) than seen in singleton pregnancies (T5) [1].

• Despite this observation, I tend not to lower my intrathecal bupivacaine dose in twin pregnancies as I do not want to compromise the block density. Additionally, block height tends not to ascend to compromising levels with normal term doses.

References

1. Jawan et al. Spread of spinal anaesthesia for cesarean section in singleton and twin pregnancies. BJA 1993;70:639-641.

Pre-Term multi-gestation

Summary

• Dose:

  • Warning: Zero evidence zone.

  • Step 1: Review recent ultrasound to ascertain estimated weight of each fetus.

  • Step 2: Add the weights together to estimate a singleton pregnancy.

  • Step 3: Choose dose of 0.5% hyperbaric bupivacaine based on table below.

  • Combine with 15 mcg fentanyl + 100 mcg morphine.

• Position: Sitting or lateral, immediately supine.

• Expectation: Surgical block for up to 90 minutes post-spinal.

Example

• 28/40 twin pregnancy with each fetus estimated to be 1000 g. This is arguably comparable to a 2000 g singleton pregnancy (equivalent ~32/40). So I would administer 2.6 ml 0.5% hyperbaric bupivacaine + 15 mcg fentanyl + 100 mcg morphine.

Evidence

• Please refer to Cesarean Section (Pre-Term/IUGR) page for evidence regarding the need to increase dose of 0.5% hyperbaric bupivacaine in cases of low birth weight.