Pain relief in labour

Question 1

What things other than medication can improve symptoms of pregnancy pain?

Answer 1

Changing position to stay comfortable
Controlled breathing
Water births may help some women
TENS machines may be useful in the early stages of labour

Question 2

Pain relief options in labour?

Side effects?

Answer 2

Simple Analgesia

Paracetamol is frequently used in early labour. Codeine may be added for additional effect. NSAIDs are avoided.

Gas and Air (Entonox)

Gas and air contains a mixture of 50% nitrous oxide and 50% oxygen. This is used during contractions for short term pain relief. The woman takes deep breaths using a mouthpiece at the start of a contraction, then stops using it as the contraction eases. It can cause lightheadedness, nausea or sleepiness.

Intramuscular Pethidine or Diamorphine

Pethidine and diamorphine are opioid medications, usually given by intramuscular injection. They may help with anxiety and distress. They may cause drowsiness or nausea in the mother, and can cause respiratory depression in the neonate if given too close to birth. The effect on the baby may make the first feed more difficult.

Patient Controlled Analgesia

Patients may be offered the option of patient-controlled intravenous remifentanil. This involves the patient pressing a button at the start of a contraction to administer a bolus of this short-acting opiate medication.

Patient-controlled analgesia requires careful monitoring. There needs to be input from an anaesthetist, and facilities in place if adverse events occur. This includes access to naloxone for respiratory depression, and atropine for bradycardia.

Epidural

An epidural involves inserting a small tube (catheter) into the epidural space in the lower back. Local anaesthetic medications are infused through the catheter into the epidural space, where they diffuse to the surrounding tissues and through to the spinal cord. Anaesthetic options are levobupivacaine or bupivacaine, usually mixed with fentanyl.

Adverse effects:

Headache after insertion
Hypotension
Motor weakness in the legs
Nerve damage
Prolonged second stage
Increased probability of instrumental delivery

Women need urgent anaesthetic review if they develop significant motor weakness (unable to straight leg raise). The catheter may be incorrectly sited in the subarachnoid space (within the spinal cord), rather than the epidural space.