200 likes | 582 Views
Intrapartum Epidural Anaesthesia. Max Brinsmead PhD FRANZCOG March 2013. This talk will cover. Evidence for risks and benefits associated with this method of analgesia in labour Recommended information for patients Indications and contraindications Recommended agents & techniques
E N D
Intrapartum Epidural Anaesthesia Max Brinsmead PhD FRANZCOG March 2013
This talk will cover... • Evidence for risks and benefits associated with this method of analgesia in labour • Recommended information for patients • Indications and contraindications • Recommended agents & techniques • Observations required with epidurals • Modifications to intrapartum care that are recommended
Benefits and Risks of Epidural AnaesthesiaWhat is the Evidence? • There has been only one RCT of epidural vs placebo • A study of 132 nulliparas published 1999 in Spanish • This found that the procedure… • Is highly effective for 91% of women • Shortens the 1st stage of labour • Has no effect on second stage labour • And no effect on any other birth outcome
Cochrane Systematic Review (2005) • 17 studies involving 6664 women • Epidural compared by RCT to “all other methods of analgesia” (mostly narcotics) • The procedure is significantly associated with… • Much better pain relief • Longer second stage (WMD 19 min, CI 11-27 min) • More assisted births (RR 1.34, CI 1.12-1.50) • More need for oxytocin infusion in the 2nd stage (RR 1.19, CI 1.02-1.38) • Maternal hypotension (RR 58, CI 21-161) • Maternal fever (RR 4.37, CI 2.99-6.38) • Urine retention (RR 17, CI 4.8-60) • Urine incontinence postpartum (but gone by 3m and 12m)
Cochrane Review of RCT’s (2005) • Found no significant differences in… • Any measure of baby outcome • Low cord pH • Apgar scores • Admission to SCN • Less Naloxone required • Rate of Caesarean birth • Women’s satisfaction with pain relief and their birth experience • Length of first stage of labour • Perineal trauma • Headache • Long term back ache • Breast feeding
What about Walking Epidurals? • I have yet to encounter a patient walking about after an intrapartum epidural • A Cochrane meta analysis (2005) of the 4 – 7 trials that used only modern low dose anaesthetic agents (≤0.25% bupivicaine or equivalent) in 4324 women found… • Substantially the same outcomes i.e… • Longer second stage • Fewer spontaneous births • More oxytocin augmentations
Are Epidurals better for Babies? • A systematic review of 8 RCT’s, 2268 women and 2 non-RCT’s, 185 women • Umbilical artery pH significantly better after epidural anaesthesia (WMD=0.009, CI 0.002-0.015) • As was Base Excess (WMD=0.779 mEq/L) • This implies better placental perfusion and placental gas exchange
Do Epidurals affect the mechanism of birth? • A prospective cohort study in the US published 2005 • 1439 women with epidural compared to 123 without • Head position studied using ultrasound at the time of recruitment, beginning and end of second stage of labour • Corrected for other factors including the reason for the epidural • Epidural anaesthesia was associated with an increased rate of persisting OP (but not OT) position (12.9% vs 3.3% or OR 3.5, CI 1.2-9.9)
Is PCA Narcotic Analgesia a substitute for Epidural Anaesthesia in Labour? • Most studies confirm the findings of Epidural CF all “other forms of analgesia” • Pain scores are significantly lower after epidural but maternal satisfaction is the same • One RCT of 715 women in the US showed longer 1st stage labour after epidural (WMD 1.2 hrs) • This could be overcome by using oxytocin infusion
Common side effects of Epidural • IV access required as hypotension can occur • About 10% • Counteract with IV fluids, rarely pressors • Pre-loading with IV fluid no longer required before modern dose regimens • At least 50% of patients require bladder catheter • Up to 66% patients given opioids in the epidural will experience pruritis • Nausea and shivering less common
Rare Complications of Intrapartum Epidurals • Accidental dural tap • Rate depends on operator experience (0.5 – 1%) • At least 50% associated with severe headache • And 25 – 30 % require a blood patch • Accidental intravenous injection of agent • Accidental spinal block • Total paralysis & profound CVS collapse reverses over time • Epidural haematoma • Platelet count desirable in at-risk patients e.g. pre eclampsia • Infection • Catheter site infection • Meningitis • Epidural abscess • Meticulous site care required and timely removal • Neurological injury • It is very difficult to get incidence rates for the above rare outcomes • Lost catheter tip
What should women be told about Epidurals? • NICE Recommendations • Information about local availability • It is more effective than other means of pain relief • It is associated with a longer second stage and reduced rate of spontaneous birth • It requires IV access and increased maternal and fetal monitoring • This should not result in an increased rate of CS • It does not cause long term back problems • If the agent used contains an opoid then this can reach the newborn with some effects • My additions • The risk of spinal tap is ≈1% • There are other very rare risks and complications
Indications for Intrapartum Epidural Anaesthesia • Pain management in the first stage of labour • Spontaneous or induced labour • Rate then depends on patient request or • Availability of services • Ideally fully informed patients • And unlimited service by skilled anaesthetists • Anaesthesia for 2nd and 3rd stage interventions • Assisted delivery and perineal repair • Hypertension and seizure control for pre eclampsia
Contraindications to Intrapartum Epidural Anaesthesia • High risk of haematoma • Patient anticoagulated • Platelet count ideally >100 • 50 – 100 is a grey zone (anaesthetists vary) • High risk of sepsis • Need for high anaesthesia, respiratory assistance or unstable CVS system • Placenta previa • Relative contraindications • Obesity • Patient psyche
Best Techniques & Agents for Intrapartum Epidural Anaesthesia • Combined spinal-epidural best for rapid pain control • Use low dose bupivicaine e.g. 0.1% or less with 2 ug/ml Fentanyl and boluses of 10 – 15 ml • Patient controlled maintenance (PCEA) or midwife administered top-ups result in lower overall doses of agents • And are preferred by patients • Should be encouraged to adopt their degree of block and position of choice for labour
When should an Epidural be inserted? • There is evidence that lower doses of analgesia are required if it commenced sooner rather than later • Some evidence of a shorter 1st stage labour when epidurals are used early • Women certainly appreciate it • NICE recommends… • “Women in labour who desire regional anaesthesia should not be denied it, including women in severe pain in the latent phase of the 1st stage”
NICE Recommended Observations after Epidural • BP every 5 min for 15 min after 1st block and every top up • Recall the anaesthetist if the woman is not pain-free after 30 min • Hourly assessment of level of block • Otherwise routine maternal observations • CTG during and for 30 min after 1st block and every top up >10 ml • ↓STV can occur • Bradycardia can occur with intrathecal opiods
NICE Recommendations for management of the 2nd stage after Epidural • Do NOT discontinue or reduce the anaesthesia until the 3rd stage or perineal repair is complete • Use oxytocin when clinically indicated (not as a routine) • PUSH when… • The mother wants to (and Cx is fully dilated) • The head is visible • Cx has been fully dilated for one hour • Deliver within 4 hours of full dilatation (regardless of parity)