The extension of epidural blockade for emergency Caesarean section: a survey of current UK practice*

Intravenous lipid emulsion for local anaesthetic systemic toxicity in pregnant women: a scoping review

BACKGROUND

Local anaesthetic systemic toxicity (LAST) is a rare but life-threatening complication that can occur after local anaesthetic administration. Various clinical guidelines recommend an intravenous lipid emulsion as a treatment for local anaesthetic-induced cardiac arrest. However, its therapeutic application in pregnant patients has not yet been established. This scoping review aims to systematically identify and map the evidence on the efficacy and safety of intravenous lipid emulsion for treating LAST during pregnancy.

METHOD

We searched electronic databases (Medline, Embase and Cochrane Central Register Controlled Trials) and a clinical registry (lipidrescue.org) from inception to Sep 30, 2022. No restriction was placed on the year of publication or the language. We included any study design containing primary data on obstetric patients with signs and symptoms of LAST.

RESULTS

After eliminating duplicates, we screened 8,370 titles and abstracts, retrieving 41 full-text articles. We identified 22 women who developed LAST during pregnancy and childbirth, all presented as case reports or series. The most frequent causes of LAST were drug overdose and intravascular migration of the epidural catheter followed by wrong-route drug errors (i.e. intravenous anaesthetic administration). Of the 15 women who received lipid emulsions, all survived and none sustained lasting neurological or cardiovascular damage related to LAST. No adverse events or side effects following intravenous lipid emulsion administration were reported in mothers or neonates. Five of the seven women who did not receive lipid emulsions survived; however, the other two died.

CONCLUSION

Studies on the efficacy and safety of lipids in pregnancy are scarce. Further studies with appropriate comparison groups are needed to provide more robust evidence. It will also be necessary to accumulate data-including adverse events-to enable clinicians to conduct risk-benefit analyses of lipids and to facilitate evidence-based decision-making for clinical practice.

Quick Epidural Top-up with Alkalinized Lidocaine for emergent caesarean delivery (QETAL study): protocol for a randomized, controlled, bicentric trial

BACKGROUND

General anesthesia in pregnant women can be associated with significant maternal and fetal morbidity. Emergency caesarean section can be performed by converting labor epidural analgesia to surgical anesthesia by injecting high-dose short-acting local anesthetics through the epidural catheter. The effectiveness and the delay to obtain surgical anesthesia depends upon the protocol used. Data indicate that alkalinization of local anesthetics may shorten their onset of action and increase their effectiveness. This study investigates whether alkalinization of adrenalized lidocaine could increase the efficacy and decrease the delay of onset of surgical anesthesia via an indwelling epidural catheter, thus decreasing the necessity to resort to general anesthesia for emergency caesarean deliveries.

METHODS

This study will be a bicentric, double-blind, randomized, controlled trial with two parallel groups of 66 women who require emergency caesarian deliveries and who have been receiving epidural labor analgesia. The number of subjects in groups will be unbalanced with a 2:1 ratio of experimental:control. In both groups, all eligible patients will have had an epidural catheter placed for labor analgesia with levobupicaine or ropivacaine. Patient randomization will occur when the decision is made by the surgeon that an emergency caesarean delivery is indicated. Surgical anesthesia will be obtained by injecting 20 mL of 2% lidocaine with epinephrine 1:200,000, or 10 mL 2% lidocaine with epinephrine 1:200,000 plus 2 mL sodium bicarbonate 4.2% (total of 12 mL). The primary outcome will be the rate of conversion to general anesthesia for failure of the epidural to provide adequate analgesia. This study will be powered to detect a 50% reduction in the incidence of general anesthesia, from 80 to 40%, with a confidence ratio of 90%.

DISCUSSION

Sodium bicarbonate could be used to avoid general anesthesia for emergency caesarean deliveries by providing reliable and effective surgical anesthesia in women with pre-existing labor epidural catheters is promising. This randomized controlled trial seeks to determine the optimal local anesthetic mixture for converting epidural analgesia to surgical anesthesia for emergency caesarean sections. This may decrease the need for general anesthesia for emergency caesarian section, shorten the time to fetal extraction, and improve safety and patient satisfaction.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05313256. Registered on 6 April 2022.

A Prospective Randomized Trial of Ropivacaine 5 mg with Sufentanil 2.5 μg as a Test Dose for Detecting Epidural and Intrathecal Injection in Obstetric Patients

Objectives: Traditional epidural test dose is somewhat unsuited in obstetrics because of potential risk of severe adverse effects when it is accidentally injected into the subarachnoid space. Some hospitals use a proportion of the total dose of epidural labor analgesia as a test dose. The aim of our study was to assess the effectiveness and safety of ropivacaine 5 mg with sufentanil 2.5 μg to detect intrathecal injection. Methods: This prospective randomized study enrolled parturients who had the demand for epidural labor analgesia and randomly divided them into two groups. Then, 5 mL of 0.1% ropivacaine with sufentanil 2.5 μg was injected into the epidural space or the subarachnoid space in the epidural (EP) group and the intrathecal (IT) group, respectively. The ability to detect intrathecal injection and side effects were assessed to work out the effectiveness and safety. Results: For spinal injection, the sensitivity and the specificity of the symptoms of either warmth or numbness or both assessed at 3 min were both 100%, and the observed negative predictive value (NPV) and positive predictive value (PPV) were 100%. All parturients in the IT group and 2.33% of parturients in the EP group had sensory blockade to cold or pinprick (p < 0.0001). A total of 77.55% (38 of 49) of parturients in the IT group were found to have a motor block. A 10 min assessment showed the median cephalad cold and pin levels were T8 and T10, respectively, and the median Bromage score was 4 in the IT group. Incidences of adverse effects in both groups were low. Conclusions: Ropivacaine 5 mg with sufentanil 2.5 μg is effective and safe to detect intrathecal injection as an epidural test dose in obstetric patients.

Prolonged duration of epidural labour analgesia decreases the success rate of epidural anaesthesia for caesarean section

OBJECTIVE

To summarise the process of conversion of epidural labour analgesia to anaesthesia for caesarean delivery and explore the relationship between duration of labour analgesia and conversion.

METHODS

Parturients who underwent conversion from epidural labour analgesia to anaesthesia for caesarean delivery between May 2019 and April 2020 at the Chengdu Women's and Children's Central Hospital, Sichuan Maternal and Child Health Hospital, and Jinjiang District Maternal and Child Health Hospital were selected. If the position of the epidural catheter was correct and the effect was good, patients were converted to epidural surgical anaesthesia. If epidural labour analgesia was ineffective, spinal anaesthesia (SA) was administered immediately. For category-1 emergency caesarean sections, general anaesthesia (GA) was administered.

RESULTS

A total of 1084 parturients underwent conversion. Of these, 19 (1.9%) received GA due to the initiation of category-1 emergency caesarean section. 704 (64.9%) were converted to epidural surgical anaesthesia, 2 (0.2%) had failed conversions and were administered GA before delivery, and 357 (32.9%) were converted to SA. Logistic regression analysis showed that prolonged duration of epidural labour analgesia ([Crude odds ratio (OR)=1.065; 95% confidence interval (CI), 1.037-1.094; p < .01]; [Adjusted OR = 1.060; 95% CI, 1.031-1.091; p < .01]) was an independent risk factor for conversion failure. A receiver operating characteristic curve constructed using duration of epidural labour analgesia showed that parturients with a duration of epidural labour analgesia ≥8 h, more frequently required a change of anaesthesia technique during conversion, and the relative risk of conversion failure was 1.54 (95% CI, 1.23-1.93; p < .01).

CONCLUSION

Prolonged duration of epidural labour analgesia increases the possibility of having an invalid epidural catheter, resulting in an increased risk of conversion failure from epidural labour analgesia to epidural surgical anaesthesia. Further, this risk is higher when the time exceeds 8 h. KEY MESSAGESProlonged duration of epidural labour analgesia > 8 h is associated with conversion failure.If it is impossible to judge whether the conversion is successful immediately, spinal anaesthesia should be administered to minimise complications.

Neuraxial and general anaesthesia for caesarean section

Caesarean section (CS) is one of the most performed operations worldwide. In many parts of the world, there has been a reduction in anaesthetic associated obstetric mortality, and this has been attributed to the increased use of neuraxial anaesthesia and improved safety of general anaesthesia, alongside improved training and organisational changes. In resource-limited countries, anaesthesia contributes disproportionately to maternal mortality, with one in seven deaths being due to anaesthesia. A major contributory factor to this is the severe shortage of trained anaesthetic providers. Goals for anaesthesia for CS include the woman's comfort and foetal well-being, focusing on strategies to minimise morbidity and mortality for both. Anaesthetic options for CS include neuraxial techniques (spinal or combined-spinal epidural or epidural extension of labour analgesia) and general anaesthesia. There is increasing evidence of the benefit of neuraxial techniques over general anaesthesia in terms of maternal and foetal outcomes. For elective CS, spinal and combined-spinal anaesthesia predominate. General anaesthesia is mainly reserved for Category 1 CS where there is an immediate threat to the life of the mother or the baby. This review discusses the practical aspects of neuraxial and general anaesthesia for CS.

Learning from the law: a review of 21 years of litigation for anaesthetic negligence resulting in peripartum hypoxic ischaemic encephalopathy

One of the most devastating complications that can result from medical mismanagement during labour and delivery is hypoxic ischaemic encephalopathy. Hypoxic ischaemic encephalopathy has profound implications for the newborn and its family, as well as for the healthcare team involved. Hypoxic ischaemic encephalopathy can take only minutes to develop, but the repercussions of this complication can last a lifetime. A proportion of these injuries arise from failure to deliver the baby within a sufficiently short time frame once fetal compromise has been recognised. Obstetric anaesthetists are often involved in such claims, usually in relation to a perception that provision of anaesthesia for caesarean section was unduly delayed. In the following article, using a database of over 360 cases spanning 21 years, we break down and examine the recurrent components of medicolegal claims concerning the anaesthetic involvement in hypoxic ischaemic encephalopathy, and consider how increased awareness of the anaesthetic contribution to this complication might reduce future harm, improve clinical standards and consequently decrease the need for litigation.

Anesthetic Conversion of Preexisting Labor Epidural Analgesia for Emergency Cesarean Section and Efficacy of Levobupivacaine with or Without Magnesium Sulphate: A Prospective Randomized Study

Background: For pregnant women who require an emergency cesarean section (CS), extending labor epidural analgesia as quickly as feasible to good quality anesthesia is a critical issue. This indicates the presence of functional labor epidural analgesia and reduces the need for general anesthesia. Addition of magnesium increases anesthetic and analgesic qualities of epidural anesthesia. Objectives: The purpose of this trial was to assess the role of adding magnesium sulfate (MgSO4) with levobupivacaine to speed up the conversion of labor epidural analgesia into enough anesthesia for emergency CS. Methods: Fifty parturients were randomly assigned to receive 19.5 mL of levobupivacaine 0.5% with either 0.5 mL of normal saline 0.9% (Group I) or 0.5 mL of MgSO4 10% (Group II) after receiving labor epidural analgesia. We documented the onset of block (loss of pinprick to T6), number of patients needing additional analgesia, the time needed for sensory and motor blockade to recover, and the adverse effects. Results: The frequency of patients receiving intraoperative supplements was comparable in the study groups (P = 0.491), although the onset of the block was faster in Group II than in Group I (P = 0.000*). Group II took substantially longer to recover from sensory and motor blockade than Group I (P = 0.001* and P = 0.001*, respectively). In both groups, the occurrence of adverse events was similar. Conclusions: Adding 50 mg of MgSO4 to levobupivacaine 0.5% accelerated the epidural top, and both sensory onset and motor blocks period were prolonged as compared to levobupivacaine alone when extending epidural analgesia for emergency CS.

Risk factors for labor epidural conversion failure requiring general anesthesia for cesarean delivery

Background and Aims:

To evaluate the rate and risk factors of labor epidural conversion failure requiring general anesthesia for Caesarean delivery (CD).

Material and Methods:

Pregnant patients requiring conversion from labor to CD with a pre-existing labor epidural at our institution from 2009 to 2014 were identified. Through a retrospective review, we compared successful epidural conversion with those who required general anesthesia for CD. Patient characteristics were analyzed to identify risk factors for failed epidural conversion for CD.

Results:

A total of 673 patients were included in the study. The rate of epidural conversion failure was 21%. Main risk factors for epidural conversion failure requiring general anesthesia included: younger maternal age (95% CI 0.94, P = 0.0002) and supplementation of intravenous fentanyl (95% CI 0.19, P < 0.0001) or midazolam (95% CI 0.26, P = 0.0008) during CD. A higher risk of conversion failure was also associated with a more urgent CD (CD category 1, 2, and 3 vs category 4).

Conclusion:

Consistent with previous reports, young age and the urgency of CD increases the likelihood of epidural conversion failure. While conversion failure is likely multifactorial and complex, many of these factors are suggestive of inadequate and poorly functioning labor epidurals prior to CD. Prospective studies to further evaluate these factors are necessary, and the best prevention of epidural conversion failure is diligent diagnosis and evaluation of ineffective labor epidural analgesia prior to impending CD.

Epidural augmentation for urgent Cesarean Section : a nationwide Israeli survey

Background : Epidural augmentation to convert analgesia to emergency cesarean delivery anesthesia is a common practice. In this survey we examined the common augmentation practices in different hospitals in Israel. We investigated whether practices vary by hospital size and if written protocols for conversion correlate with intra-hospital homogeneity. Methods : A questionnaire containing 39 questions was sent to obstetric anesthesia unit heads and to four additional anesthesiologists (attending and residents) in 24 obstetric anesthesia units nationwide. Answers were received online anonymously using web-based survey site. Results : 99/120 participants responded to the survey. 80% of large hospitals have a detailed epidural augmentation protocol. The existence of a written protocol does not affect intrahospital management variability. Overall, 18 different drug mixtures for epidural augmentation were reported, and the most used drug combination is lidocaine, fentanyl and bicarbonate. In large hospitals, 72% add epinephrine and 96% initiate augmentation before operating room arrival. Most respondents reported a final administered total volume of 15-20 ml. In most hospitals there is no maternal or fetal monitoring during patient transfer from delivery room to the operating room, lasting 3.68 minutes on average, with a relative low risk of significant complication as a result of augmentation. Conclusion : We report variations in common practices, depending on hospital size. We recognized low rate of intra-hospital concordance between centers with or without a written protocol of augmentation. Regarding points for improvement, we would recommend adhering to the accepted institutional protocol.

Extending epidural analgesia for intrapartum cesarean section following epidural labor analgesia: a retrospective cohort study

Objective: To determine the effectiveness of extending epidural analgesia following epidural labor analgesia for intrapartum cesarean section, and provide a reference for clinical practice.Methods: Data of 1254 singleton parturient who failed trial of epidural labor analgesia and underwent intrapartum cesarean section were retrospectively included. After entering the operating room, parturient were given 3 ml of 1.5% lidocaine with 1:200,000 epinephrine 15 µg as a test dose, followed by a dose of 10 ml 0.75% ropivacaine plus 5 ml of 2% lidocaine mixed solution was administered via the epidural catheter. Case data were reviewed and analyzed of cesarean section anesthesia implementation methods, results and maternal and neonatal outcomes.Results: Of the 1254 parturient, 4.7% (59 of 1254) underwent general anesthesia directly, 7.1% (89 of 1254) were given combined spinal and epidural anesthesia, and the other 88.2% (1106 of 1254) underwent extending epidural anesthesia, 3.5% (39 of 1106) of them were given general anesthesia after extending epidural anesthesia failed, and 96.5% (1067 of 1106) parturient have a successful extending epidural anesthesia. Adverse reactions of extending epidural anesthesia: 6.7% (72 of 1067) parturient experienced hypotension and 12.1% (129 of 1067) of nausea and vomiting occurred. For the neonatal Apgar scores at 1 min, eleven of 1254 (0.9%) newborns were between 0 and 3 points, 107 (8.5%) newborns between 4 and 7 points, and 1136 (90.6%) newborns Apgar scores between 8 and 10 point. 24 (1.9%) newborns with Apgar scores between 4 to 7 points at 5 min transferred to the department of neonatology, and the rest 1230 (98.1%) newborns with Apgar scores 8-10 points.Conclusion: Extending epidural analgesia using the well-functioning epidural catheter for epidural labor analgesia might be a reliable and effective anesthetic method for intrapartum cesarean section.

Epidural test dose in obstetric patients: should we still use it?

PURPOSE OF REVIEW

As the application of a test dose after epidural catheter insertion in obstetrics has recurrently been associated with serious adverse events affecting both maternal and foetal outcomes, the question whether to test or not remains a controversial issue.

RECENT FINDINGS

Present guidelines do not provide clear recommendations in this regard and several recent surveys indicate a heterogeneity in clinical routine.

SUMMARY

Physiological alterations during pregnancy and labour restrict the use and also the validity of traditional test agents. Epinephrine is not appropriate to detect a vascular insertion in labour and the application of a local anaesthetic test dose may lead to dose-dependent fatal consequences should the catheter be intrathecal, due to an increased sensitivity in parturients. Given the current practice of opioid-amended-low-concentration epidurals, the waiving of a test dose results at worst in a failed epidural, a stark contrast to the potentially severe to fatal complications of a 'traditional' test dose. Hence, an originally preventive measure providing potentially more harm than the consequences of the situation aimed to prevent, should not be recommended. A simple fractionated administration of the initial analgesic dose seems reasonable though.

Anaesthetic management of obstetric emergencies

Obstetric emergencies are a challenge both for the obstetrician and the anaesthesiologist. The incidence of caesarean sections as per the National Family Health Survey published in 2015–16 was 17.2%. In 7.6% of cases, the decision to conduct a caesarean section was taken after the onset of labour pains. Caesarean sections are classified depending on the urgency into four categories. The target decision to delivery interval for category 1 caesarean section is less than 30 min. This is used as an audit tool for the efficiency of an obstetric service. The management of these emergencies involves a rapid assessment, with minimal investigations. Although general anaesthesia is considered to have higher morbidity and mortality, category 1 caesarean sections may still warrant this technique. Rapid sequence spinal anaesthesia is replacing general anaesthesia for many of the category 1 indications. In category 2 and 3 caesarean sections, spinal anaesthesia still remains the technique of choice. Failed intubation, failed neuraxial block, extensive neuraxial block, awareness under anaesthesia, thromboembolism, amniotic fluid embolism, haemorrhage and maternal collapse are some of the complications. Haemorrhage is said to be the leading cause of mortality worldwide.

Suspected total spinal in patient having emergent Caesarean section, a case report and literature review

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Emergent Caesarean section should be classified in accordance to the treat of mother and child, e.g. with the Lucas grading score.

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Anaesthetic technique for emergent Caesarean section is not well defined.

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Category 1 emergent Caesarean section should preferentially be formed with general anaesthesia to ascertain shortest decision-to-delivery interval.

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Anaesthetic technique for category 2/3 emergent Caesarean section should be based on an individual assessment, top-up epidural and convert spinal are both feasible option.

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When convert spinal is used the dose should possibly reduced considering the risk for too high block caused by cephalic spread.

Introduction

Epidural analgesia is commonly used for management of pain during childbirth. Need for emergent Caesarean section e.g. because of signs of foetal distress or lack of progress is however not an uncommon event. In females having an established epidural; general anaesthesia, top-up of the epidural or putting a spinal are all possible options. Dosing of the spinal anaesthesia in females having epidural is a matter of discussion.

Presentation of case

We describe a healthy 32 years, 0 para mother in gestation week 36 having labour epidural analgesia but due to foetal distress scheduled for an emergent Caesarean section category 2 that developed upper extremity weakness and respiratory depression after administration of standard dose high density bupivacaine/morphine/fentanyl intrathecal anaesthesia. She was emergent intubated and resumed motor function after 15–20 min.

Discussion

A too extensive cephalic spread was the most plausible explanation to the event. Whether or not reducing the dose for a spinal anaesthesia in mothers having an established labour epidural analgesia is a matter of discussion. It is of course of importance to achieve a rapid and effective surgical anaesthesia but also avoiding overdosing with the risk for a too high cephalic spread.

Concluiosn

To perform spinal anaesthesia for emergent Caesarean in patients having an epidural for labour pain is a feasible option and should be considered in category 2–3 section. The dose for a convert spinal block should be assessed on an individual basis and reasonably reduced.

Algorithm for the anesthetic management of cesarean delivery in patients with unsatisfactory labor epidural analgesia

The management of a patient presenting with unsatisfactory labor epidural analgesia poses a severe challenge for the anesthetist wanting to provide safe anesthetic care for a cesarean delivery. Early recognition of unsatisfactory labor analgesia allows for replacement of the epidural catheter. The decision to convert labor epidural analgesia to anesthesia for cesarean delivery is based on the urgency of the cesarean delivery, airway examination, and the existence of a residual sensory and motor block.  We suggest an algorithm which is implemented in our department, based on the urgency of the cesarean delivery.

Local anesthetic toxicity and lipid resuscitation in pregnancy

PURPOSE OF REVIEW

Lipid emulsion has emerged as an effective treatment of local anesthetic-induced cardiac arrest, but its therapeutic application for the obstetric patient requires definition at present. This review discusses clinical reports, relevant laboratory studies, and future directions for the development of an optimal protocol for lipid resuscitation in pregnancy.

RECENT FINDINGS

Several mechanisms have been postulated to account for the apparent enhanced sensitivity to local anesthetic systemic toxicity during pregnancy. One case report of lipid resuscitation in the pregnant patient demonstrates favorable outcomes and supports the safety of lipid therapy. Current guidelines and case reports propose that a large bolus of lipid at the earliest signs of toxicity may prevent cardiovascular collapse.

SUMMARY

As the obstetric demographic becomes older and more obese, new technologies and strategies can assist in controlling maternal death and major morbidity secondary to anesthesia complications. Lipid resuscitation appears to be an effective treatment for toxicity induced by lipophilic medications and may be useful in treating systemic toxicity in the pregnant patient. Obstetric care providers should be aware of lipid resuscitation and consider its use as described by American Society of Regional Anesthesia and Pain Medicine guidelines.

A survey of perioperative and postoperative anesthetic practices for cesarean delivery

The aim of this survey was to review cesarean delivery anesthetic practices. An online survey was sent to members of the Society of Obstetric Anesthesia and Perinatology (SOAP). The mode of anesthesia, preferred neuraxial local anesthetic and opioid agents, postoperative analgesic regimens, and monitoring modalities were assessed. 384 responses from 1,081 online survey requests were received (response rate = 36%). Spinal anesthesia is most commonly used for elective cesarean delivery (85% respondents), with 90% of these respondents preferring hyperbaric bupivacaine 0.75%. 79% used intrathecal fentanyl and 77% used morphine (median [range] dose 200 mcg [50–400]). 91% use respiratory rate, 61% use sedation scores, and 30% use pulse oximetry to monitor for postoperative respiratory depression after administration of neuraxial opioids. Postoperative analgesic regimens include: nonsteroidal anti-inflammatory agents, acetaminophen, oxycodone, and hydrocodone by 81%, 45%, 25%, and 27% respondents respectively. The majority of respondents use spinal anesthesia and neuraxial opioids for cesarean delivery anesthesia. There is marked variability in practices for monitoring respiratory depression postdelivery and for providing postoperative analgesia. These results may not be indicative of overall practice in the United States due to the select group of anesthesiologists surveyed and the low response rate.

Anaesthesia for urgent (grade 1) caesarean section

PURPOSE OF REVIEW

We describe the different possible anaesthetic techniques for an emergency caesarean section. To choose the right method of anaesthesia may have major implications for mother, child and all involved personnel. The major controversy is whether one have other or better alternatives or both than general anaesthesia, with a rapid sequence induction technique, when the foetus is compromised.

RECENT FINDINGS

Recently published studies indicate that a top-up of a well functioning labour epidural is as fast as general anaesthesia, and that the top-up can be performed during preparation and transport. Spinal anaesthesia, when performed by skilled anaesthetists, is as fast or almost as fast as general anaesthesia with a very low failure rate. Combined spinal/epidural may have advantages, especially in high-risk cardiac patients, but is too time-consuming. General anaesthesia still seems to be the method of choice for most anaesthetists in extremely urgent settings. The major disadvantage with general anaesthesia is the risk of failure and the dramatic consequences of a 'cannot intubate, cannot ventilate' situation. Awareness is another concern, and the incidence varies from 0.26 to 1% in recent literature.

SUMMARY

Regional anaesthesia techniques such as a single-shot spinal or a top-up of a well functioning labour epidural analgesia are good alternatives to general anaesthesia in an emergency caesarean setting.

Current world literature

This bibliography is compiled by clinicians from the journals listed at the end of this publication. It is based on literature entered into our database between 1 February 2008 and 31 January 2009 (articles are generally added to the database about two and a half months after publication). In addition, the bibliography contains every paper annotated by reviewers; these references were obtained from a variety of bibliographic databases and published between the beginning of the review period and the time of going to press. The bibliography has been grouped into topics that relate to the reviews in this issue.

Comparison of 2% Lignocaine with Adrenaline and Fentanyl, 0.75% Ropivacaine and 0.5% Levobupivacaine for Extension of Epidural Analgesia for Urgent Caesarean Section after Low Dose Epidural Infusion during Labour

Low dose local anaesthetic and fentanyl epidural solutions are commonly ‘topped-up’ for urgent caesarean section. However, the block characteristics associated with newer local anaesthetics such as ropivacaine 0.75% and levobupivacaine 0.5% have not been fully determined. In a randomised double-blinded controlled clinical trial, we compared 2% lignocaine with adrenaline and fentanyl (LAF), 0.75% ropivacaine and 0.5% levobupivacaine for extension of low dose epidural analgesia for urgent caesarean section in 90 Asian parturients.

There was no significant difference in the median, interquartile range, time to T4 loss of sensation to cold between LAF (9.5, 7.0 to 13.3 minutes), 0.75% ropivacaine (10.0, 7.0 to 15.0 minutes) and 0.5% levobupivacaine (10.0, 7.0 to 15.0 minutes). No woman required conversion to general anaesthesia. The supplementation rate did not differ between groups. Levobupivacaine provided a longer duration of sensory block compared to LAF, but a similar duration to 0.75% ropivacaine.

Under the conditions of this study there was no significant difference in time to surgical readiness (defined as loss of sensation to cold to T4) between LAF, 0.75% ropivacaine and 0.5% levobupivacaine groups. Ropivacaine and levobupivacaine are suitable alternatives for extending epidural analgesia for urgent caesarean section.