The association of anesthesia in the sitting beach-chair position with intra-operative stroke, continues to be controversial. Although some studies have identified this as a risk, it is still a rare complication, albeit devastating.
Expert opinion suggests intra-arterial blood pressure monitoring is best practice, but most importantly with consideration for actual cerebral perfusion pressure given the sitting position.
Some research suggests regional anaesthesia, possibly combined with spontaneous ventilation GA (rather than relaxation GA with IPPV) offers unique benefits that better maintain cerebral oxygenation, although the exact difference is unclear.
Similarly, the benefit and role of non-invasive cerebral perfusion monitoring has not been conclusively shown, although it appears logical that it may offer benefit in these patients.
Case studies of patients suffering cerebral ischaemia under beach-chair, do point to combinations of poor intra-operative blood pressure management and possibly pre-existing mild cardiovascular disease (eg. hypertension) as contributing to some degree.summary
There is some evidence supporting the benefit of perioperative intravenous lignocaine/lidocaine infusion in both laparoscopic and open abdominal surgery.
The strongest evidence supports both improved analgesia and reduction in nausea, with weaker evidence suggesting faster improvement in GIT function and earlier discharge from hospital.
Safety data is reassuring but far from conclusive due to the small size of most studies.summary
Carbetocin is a long-acting synthetic oxytocin analog. Although a 100 mcg dose is currently recommended, there is still some question as to the ideal dose. Dosing as low as 20 mcg may possibly be equally effective.
Carbetocin is currently only recommended for use during elective cesarean delivery, obviating the need for a post-operative oxytocin infusion currently practiced in many countries. In some countries it is also used after vaginal delivery.
It is at least as efficacious as intravenous oxytocin, and may possibly be superior at reducing postpartum haemorrhage.
Due to it's comparatively high cost compared with oxytocin however, the economic benefit of avoiding post-operative oxytocin infusions has not been demonstrated.
In the scenario of emergency cesarean section after labor augmentation with oxytocin, a much larger dose is likely required and carbetocin cannot be recommended.
One study has suggested a post-operative analgesic benefit of carbetocin vs oxytocin, although the evidence base for this is far from conclusive.summary
A collection of landmark research articles relevant to obstetric anesthesia. Some, such as Hawkins' audits of U.S. maternal deaths, are significant because of their historical impact. Others hold direct clinical relevance for practice today.summary
Cardiac arrest is rare in pregnancy (1 in 30,000) and resuscitation is founded on the same approach used for the non-pregnant patient, focusing on:
- Calling for help
- A B C (D)
- Good for mother = good for baby
However, unique to maternal resuscitation:
- Airway difficulties are more likely.
- Aortocaval compression dramatically impedes resuscitation – employ left lateral tilt!
- Consider perimortem cesarean section
The rationale for Perimortem Cesarean Section is:
- The presence of baby and gravid uterus severely limits resuscitation of the mother.
- Emergency cesarean section at cardiac arrest is done for the mother’s benefit, not the baby.
- A decision to perform emergency CS must be made within 4 minutes of arrest, and the baby delivered within 5 minutes. (Although there is some evidence of benefit when performed up to 10 minutes after arrest.)
- The only equipment required is a scalpel and an appropriately skilled doctor.