Personal tools
  Members Area  

Skip to content. | Skip to navigation

Sections
 

Summary of Key Messages

Download pdf (pdf icon 71kB)

 

Management of Pre-Eclampsia and Eclampsia

Management of Regional Analgesia for Labour

Hypotension during Regional Anaesthesia for Caesarean Birth

Aspiration Prophylaxis for Pregnant Patients Requiring Anaesthesia

Oral Intake during Labour

 

Copyright

 

Management of Pre-Eclampsia and Eclampsia

  1. MgSO4 is the first line drug treatment for seizures (eclampsia) and for recurrent seizures (Level I).
  2. MgSO4 should be used for seizure prophylaxis in women with severe pre-eclampsia (Level I).
  3. MgSO4 should be considered for seizure prophylaxis in women with mild pre-eclampsia (Level 1).
  4. Severe hypertension is defined as systolic ≥160 mmHg or diastolic ≥ 110mmHg and should be treated (Level III-2).
  5. Elevated blood pressure should be lowered to levels of systolic blood pressure 140-150 mmHg and diastolic blood pressure 90-100 mmHg at a rate of 10-20 mmHg every 10-20 minutes. Reducing severe levels of hypertension decreases the risk of death (Level IV).
  6. Antihypertensive drugs that can be safely used include labetalol, nifedipine and hydralazine. The choice should be made on clinician familiarity and experience with a particular agent (Level I).
  7. Drugs that should be avoided for the reduction of blood pressure are diazoxide, ketanserin, nimodipine, MgSO4 (Level I) and sodium nitroprusside (Level IV).
  8. Acute pulmonary oedema is a significant case of morbidity and mortality in pre-eclampsia. Intravenous fluid management should be monitored very closely (Level II).
  9. In the absence of other coagulation abnormalities the risk of haematoma associated with regional anaesthesia with platelet counts >75x109/L is very low.
  10. Lumbar epidural analgesia in the absence of contraindications is beneficial during labour as it limits hypertensive responses to pain and provides ready opportunity for block extension for caesarean section (Level II).
  11. Regional blockade is the preferred method of anaesthesia for caesarean section (Level II). There is currently insufficient evidence to support any specific type.
  12. When general anaesthesia is required measures should be taken to ensure the intubation response is ablated (Level II).
  13. Ergometrine should be avoided due to its propensity to cause a hypertensive crisis (Level IV).
  14. A multidisciplinary team approach needs to be adopted when managing a woman with pre-eclampsia and it is important for the anaesthetist to be given as much time as possible to stabilise the woman prior to delivery.

 
Management of Regional Analgesia for Labour

  1. Regional block provides more effective pain relief when compared with systemic analgesics during labour (Level I).
  2. Intravenous fluid pre-loading prior to regional block for labour analgesia decreases the incidence of hypotension when high doses of local anaesthetic, equivalent to 25mg bupivacaine or more, are used (Level I). Routine fluid loading is not required with low dose techniques as hypotension is uncommon (Level I), but intravenous access should be established in all cases prior to regional block insertion.
  3. In view of the potential for maternal hypotension, motor block and fetal heart rate changes associated with regional block for labour analgesia, monitoring these parameters should commence immediately prior to the regional procedure and continue whilst the block is in place.
  4. A low-dose local anaesthetic test dose, such as 0.125% bupivacaine rather than a traditional lignocaine-adrenaline test dose, permits ambulation in the early post-block period for most parturients (Level II).
  5. There is no difference in analgesic effectiveness or adverse effects between ropivacaine and bupivacaine for epidural analgesia during labour (Level I).
  6. PCEA without background infusion reduces local anaesthetic use and motor block when compared with continuous epidural infusions (Level I).
  7. Both CSE and epidural regional techniques provide effective analgesia for labour, with a high degree of maternal satisfaction of at least 90%. CSE is associated with more pruritus. There are no differences in the quality of analgesia or maternal mobility if low concentrations of epidural local anaesthetic combined with opioid are used (Level I).
  8. Single injection intrathecal opioids provide comparable early analgesia to epidural local anaesthetics with less motor block but with an increased incidence of pruritus (Level I).
  9. Combination of spinal opioids such as fentanyl with local anaesthetics reduces dose requirements for either drug alone and may help minimise motor block (Level I).
  10. Regional analgesia is associated with increased duration of the second stage of labour and instrumental vaginal birth, but has no effect on the risk of a caesarean, long term backache or the immediate status of the neonate (Level I).
  11. Women should be advised, preferably in the antenatal period and with written information, of the full range of both pharmacological and non-pharmacological techniques including the risks (particularly PDPH) and benefits of regional block for labour analgesia (Level IV).
  12. Epidural analgesia should not be withheld late in labour in an attempt to reduce the rate of instrumental delivery as this practice does not affect the incidence of spontaneous vaginal birth but does increase the rate of inadequate pain relief in the second stage of labour (Level I).
  13. Early regional block for labour analgesia should be considered in obese patients and those with cardiovascular disease or obstetric indications, such as twin pregnancy or pre-eclampsia (Level IV).

 

Hypotension during Regional Anaesthesia for Caesarean Birth

  1. Hypotension is a frequent complication of neuraxial anaesthesia in obstetrics and may have detrimental effects on both mother and fetus (Level I).
  2. Hypotension is especially common during caesarean section, especially during spinal and in non-labouring patients (Level I).
  3. Definitions of hypotension vary but commonly used criteria include a decrease in systolic BP to < 80-100 mmHg or by 10-30% below baseline.
  4. Left uterine displacement should be applied to all patients after neuraxial block (Level II).
  5. Wrapping of the legs reduces the incidence of hypotension (Level II).
  6. Prehydration with crystalloid solutions has poor efficacy for preventing hypotension. Colloids have greater efficacy but this must be balanced against greater cost and potential adverse effects (Level I).
  7. The choice of vasopressor is controversial. Ephedrine preserves uterine blood flow but has limited efficacy and is associated with small decreases in fetal pH and base excess (Level I).
  8. Phenylephrine is effective and easily titrated but may decrease maternal heart rate and cardiac output (Level II).
  9. Combination of therapies, e.g. intravenous cohydration and vasopressor infusion may be more effective than single therapies for preventing hypotension (Level II).

 

Aspiration Prophylaxis for Pregnant Patients Requiring Anaesthesia

  1. Pulmonary aspiration of solids or liquids is a rare but significant cause of morbidity and mortality for pregnant women (Level IV).
  2. Multiple changes in anaesthetic and obstetric practice including the widespread adoption of regional techniques, fasting in labour, use of antacids, use of cuffed endotracheal tubes and cricoid pressure have been associated with a dramatic reduction in maternal mortality from aspiration over the last 50 years (Level IV), but the independent effects of each of these is difficult to establish.
  3. From early pregnancy, there is a reduction in lower oesophageal barrier pressure and symptomatic reflux is common but the rate of gastric emptying and basal gastric acid production due to pregnancy alone are unaltered.
  4. Labour, food in the stomach, obesity and the use of opioids are all associated with delayed gastric emptying.
  5. Particulate antacids which are commonly available over the counter are associated with more severe pneumonitis should aspiration occur.
  6. Sodium citrate 0.3 M, 30 mL given orally is the most effective means of immediate neutralisation of gastric acidity; it is effective within a few minutes and lasts up to one hour (Level II).
  7. Ranitidine is effective in a dose of 50 mg IV or 150 mg orally. There is no additional benefit from 300 mg. The onset is more rapid after IV administration, being approximately 45 minutes (Level II), while at least one hour should be allowed after oral administration (Level II). The duration of action is at least five hours.
  8. The effervescent formulation of ranitidine exhibits a biphasic action on reducing acidity and some women will have unacceptably low levels of pH at approximately 30 to 60 minutes after administration (Level III-2).
  9. The combination of sodium citrate plus ranitidine is the most effective means of reducing gastric acidity (Level II).
  10. Proton pump inhibitors are no more effective than ranitidine and are generally more expensive (Level II).
  11. Metoclopramide increases the rate of gastric emptying in some cases and is more effective after IV administration than intramuscular (Level II, III-2).
  12. Aspiration prophylaxis should be used in all women of greater than 18-20 weeks gestation, and in the postpartum period up to 18 hours post delivery (Level IV). These limits should be extended when any other factors prevail that are likely to be associated with delayed gastric emptying or there is symptomatic reflux.
  13. Routine prophylaxis with ranitidine in labour should be considered in those women who have a significant risk of requiring general anaesthesia or surgical intervention including contraindications to regional blockade, BMI >30, previous caesarean delivery, diabetes, and extremes of fetal weight. The usual schedule in this context is six-hourly dosing.

 

Oral Intake during Labour

  1. Pulmonary aspiration of solids or liquids is a rare but significant cause of morbidity and mortality for pregnant women (Level IV).
  2. Women who are fed in labour may be at a greater risk of aspirating since gastric volumes are increased (Level II) and are unpredictable (Level III-2).
  3. Opioid analgesia is associated with a delay in gastric emptying (Level II, III-2).
  4. Obesity is a predictor of increased gastric volumes in labour (Level III-1).
  5. Obesity increases the risk of airway difficulties (Level IV).
  6. Multiple changes in anaesthetic and obstetric practice including fasting in labour, use of antacids, use of cuffed endotracheal tubes, cricoid pressure and the widespread adoption of regional techniques have been associated with a dramatic reduction in maternal mortality from aspiration over the last 50 years (Level IV), but the independent effects of each of these is difficult to establish.
  7. There have to date been no cases of aspiration reported where low-risk parturients have been allowed to eat in labour (Level IV).
  8. Women fed solid food in labour are more likely to vomit (Level II) and have longer labours but this does not influence obstetric outcome (Level II).
  9. Women fasted in labour are more prone to ketosis and elevated non-esterified fatty acid levels and low glucose (Level II). However, there is no evidence that ketosis has any influence on maternal or fetal acid-base balance and no evidence that ketosis interferes with the progress of labour (Level II).
  10. Mode of delivery is not significantly influenced by the type of oral intake in labour (Level II).
  11. Isotonic calorific drinks consumed during labour reduce the incidence of maternal ketosis without increasing gastric volumes (Level II; Level III-3).
  12. Administration of intravenous glucose to fasting parturients in labour causes fluid overload and lactic acidosis in the mother and hyponatraemia in the fetus (Level III-2).
  13. On the balance of maternal comfort, obstetric outcome and risk of aspiration, an approach to management consistent with the available evidence could include:
    • Pregnant women who are not in established labour and/or are unlikely to require a surgical procedure may eat a full diet.
    • Women in established labour may take ice-chips, water and clear fluids.
    • Maintaining energy and fluid balance is an important supportive care strategy and can be achieved safely with the use of isotonic energy drinks.

 

Copyright 

This work is copyright.  Apart from use as permitted by the Copyright Act 1968, no part may be reproduced by any process without prior written permission from ANZCA.  Requests and enquiries concerning reproduction should be addressed to the Chief Executive Officer, Australian and New Zealand College of Anaesthetists, 630 St Kilda Road, Melbourne, Victoria 3004, Australia.  Website: www.anzca.edu.au    Email: ceoanzca@anzca.edu.au

 

Document Actions