Uterine relaxation techniques

Rationale:

1. manual removal of a retained placenta
2. breech delivery: obstructed after coming head or shoulders
3. multiple pregnancy: second twin in transverse-lie
4. inadvertent oxytocic overdose prior to delivery
5. uterine constriction ring
6. inverted uterus
7. (some cases of) fetal distress.

Agents used: inhalationed agents, nitrates (IV NTG:50mcg/ml. With NTG, uterine relaxation should be achievable in 75 to 90 seconds and is maintained for less than 10 minutes (without the need for general anaesthesia), INHALED amyl nitrate, Beta adrenergic agonists (IV ritodrine, IV salbutamol, IV terbutaline)

Side Effects:

1. Hypotension (uncommon in euvolaemic patients, treat w/ ephedrine and/or volume replacement
2. The effect of this dose of NTG on uterine, cervical and vaginal muscle is very transient, and any persisting loss of uterine muscle tone can be reversed with oxytocics (syntocinon +/- ergometrine).

Monitoring:

1. Repeated blood pressure monitoring.
2. Continuous fetal heart monitoring and maternal ECG or oximetry

Contraindications:

1. Significant blood loss
2. (Some cases of) valvular heart disease