Obstetric Anaesthesia Flashcards
What are the roles of the anaesthetist in obstetric care?
Pain relief for labour
Anaesthesia for instrumental/operative delivery
Input on Obstetric High Dependency Unit
Anaesthetic antenatal clinic
Which nerve roots are involved in labour pain?
T10 – L1
S2 – S4
What are the non-pharmacological therpaies for pain relief in labour?
hypnobirthing acupuncture massage TENS - trnascutaneous electric nerve stimulation hydrotherapy
what are the pharmacological methods for pain relief?
Entonox Oral analgesia ‘Single shot’ parenteral opioids PCA opioids Regional techniques - epidural, spinal, combined spinal and epidural
what are the adv and disadv of using etonox?
Adv
- rapid onset of analgesia
- minimal side effects
Disadv
- bone marrow suppression
what oral anaesthesia may women use?
paracetamol
codeine
How are opioids adminsitered in labour and what type are used?
single shot - IM: morphine, diamorphine, pethidine
PCA via IV cannula: remifentanyl, fentanyl, alfentanil
what are the main side effects of opioids?
sedation, respiratory depression, N&V, pruritus
baby can be delivered sedated if used too close to delivery
obesity - more likely to get resp depression
At what level is an epidural inserted?
L3/4
At what level does the spinal cord terminate in adults?
L2
what landmark is used to indicate L3/4?
Tuffier’s line - between the ileac crests
What layers would an epidural go through?
Skin
Spinous ligament
Ligamentum flavum
Epidural space
(a spinal needle would also go through the dural sac)
where would you put a spinal needle?
below L2/3
What are the indications for an epidural?
gestational hypertension, PET Multiple births instrumental/operative delivery likely Cardiac/other medical disease Augmented labour eg with syntocinon maternal request
what are the absolute and relative CIs for an epidural?
Absolute
- Maternal refusal
- Local infection
- Allergy to local anaesthetic
Relative
- Coagulopathy
- Systemic infection
- Hypovolaemia
- Abnormal anatomy
- Fixed cardiac output eg aortic stenosis
what are the adverse effects of an epidural or spinal?
Cardiovascular - hypotension Respiratory - resp depression Neurological - permanent nerve damage Drug related Post-dural puncture headache
May prolong labour
May increase instrumental delivery
Maternal pyrexia
What pain relief is used for operative delivery?
General Anaesthesia
Epidural top up - high conceptration epidural and opioid
Spinal - bupivacaine plus opioid
CSE
when is GA used for c-section?
Imminent threat to mother and/or foetus
Contraindication to regional
Maternal preference
Failed regional technique
What are the risks of GA?
Aspiration
Failed intubation
Awareness
what are the advantages of regional anaesthesia
Safer
Can see baby immediately
Partner present
Improved post op analgesia
what are the disadvantages of regional anaesthesia
Hypotension
Headache
Discomfort associated with pressure sensations
Failure
How does a post-dural headache present?
postural headache - better when lying down occipitofrontal neck stiffness photophobia make sure no rash
