Extension of epidural blockade in labour for emergency Caesarean section using 2% lidocaine with epinephrine and fentanyl, with or without alkalinisation

Randomized Double-Blind Study of the Effect of Injectate Temperature on Intrathecal Bupivacaine Dose Requirement in Spinal Anesthesia for Cesarean Delivery

BACKGROUND

Increasing the temperature of intrathecal local anesthetics has been shown to increase the speed of onset and block height of spinal anesthesia. However, how this influences dose requirement has not been fully quantified. The aim of this study was to determine and compare the effective dose for anesthesia for cesarean delivery in 50% of patients (ED50) of intrathecal bupivacaine given at temperatures of 37 °C (body temperature) or 24 °C (room temperature).

METHODS

Eighty healthy parturients having elective cesarean delivery under combined spinal-epidural anesthesia were randomly assigned to receive intrathecal hyperbaric bupivacaine stored at 37 °C (body temperature group) or 24 °C (room temperature group). The first subject in each group received a bupivacaine dose of 10 mg. The dose for each subsequent subject in each group was varied with an increment or decrement of 1 mg based on the response (effective or noneffective) of the previous subject. Patients for whom the dose was noneffective received epidural supplementation after data collection with lidocaine 2% as required until anesthesia was sufficient for surgery. Values for ED50 were calculated using modified up-down sequential analysis with probit analysis applied as a backup sensitivity analysis. These values were compared and the relative mean potency was calculated.

RESULTS

The ED50 (mean [95% confidence interval, CI]) of intrathecal hyperbaric bupivacaine was lower in the body temperature group (6.7 [5.7-7.6] mg) compared with the room temperature group (8.1 [7.7-8.6] mg) (P < .05). The relative potency ratio for intrathecal bupivacaine for the room temperature group versus the body temperature group was 0.84 (95% CI, 0.77-0.93).

CONCLUSIONS

Warming hyperbaric bupivacaine to body temperature reduced the dose requirement for spinal anesthesia for cesarean delivery by approximately 16% (95% CI, 7%-23%).

Risk factors for failure of conversion from epidural labor analgesia to cesarean section anesthesia and general anesthesia incidence: an updated meta-analysis

OBJECTIVES

Ongoing controversies persist regarding risk factors associated with the failure of transition from epidural labor analgesia to cesarean section anesthesia, including the duration of labor analgesia, gestational age, and body mass index (BMI). This study aims to provide an updated analysis of the incidence of conversion from epidural analgesia to general anesthesia, while evaluating and analyzing potential risk factors contributing to the failure of this transition to cesarean section anesthesia.

METHODS

We conducted an extensive literature search utilizing databases such as PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), WANGFANG, and the Chinese Biomedical Literature Database (CBM) up to September 30, 2022. The meta-analysis was performed using STATA 15.1 software. The quality of the included studies was assessed using the 11-item quality assessment scale recommended by the Agency for Healthcare Research and Quality (AHRQ).

RESULTS

A total of 9,926 studies were initially retrieved, and after rigorous selection, 19 studies were included in the meta-analysis. The overall incidence of conversion from epidural analgesia to general anesthesia was found to be 6% (95% confidence interval [CI]: 5-8%). Our findings indicate that, when compared to patients in the successful conversion group, those in the failure group tended to be younger (weighted mean difference [WMD] = -1.571, 95% CI: -1.116 to -0.975) and taller (WMD = 0.893, 95% CI: 0.018-1.767). Additionally, the failure group exhibited a higher incidence of incomplete block in epidural anesthesia, received a higher dosage of additional epidural administration, experienced a greater rate of emergency cesarean sections, and received anesthesia more frequently from non-obstetric anesthesiologists. However, no statistically significant differences were observed in gestational age, depth of the catheter insertion into the skin, epidural catheter specifics, duration of epidural analgesia, infusion rate of epidural analgesia, primiparity status, cervical dilatation during epidural placement, BMI, or weight.

CONCLUSION

Our study found that the incidence of conversion from epidural analgesia to cesarean section under general anesthesia was 6%. Notably, the failure group exhibited a higher rate of incomplete block in epidural anesthesia, a greater incidence of emergency cesarean sections, a more frequent provision of anesthesia by non-obstetric anesthesiologists, a higher dosage of epidural administration, and greater height when compared to the success group. Conversely, women in the failure group were younger in age compared to their counterparts in the success group.

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.

Risk factors for and consequences of difficult fetal extraction in emergency caesarean section. A retrospective registry-based cohort study

INTRODUCTION

This study aimed to assess risk factors for difficult fetal extraction in emergency caesarean sections, focusing on top-up epidural anesthesia compared to spinal anesthesia. Additionally, this study addressed consequences of difficult fetal extraction on neonatal and maternal morbidity.

MATERIAL AND METHODS

This retrospective registry-based cohort study included 2,332 of 2,892 emergency caesarean sections performed with local anesthesia during 2010-2017. Main outcomes were analyzed by crude and multiple adjusted logistic regression providing odds ratios.

RESULTS

Difficult fetal extraction was found in 14.9% of emergency caesarean sections. Risk-factors for difficult fetal extraction included top-up epidural anesthesia (aOR:1.37[95 %CI 1.04-1.81]), high pre-pregnancy BMI (aOR:1.41[95 %CI 1.05-1.89]), deep fetal descent (ischial spine: aOR:2.53[95 %CI 1.89-3.39], pelvic floor: aOR:3.11[95 %CI 1.32-7.33]), and anterior placental position (aOR:1.37[95 %CI 1.06-1.77]). Difficult fetal extraction was associated with increased risk of low umbilical artery pH 7.00-7.09 (aOR:3.50[95 %CI 1.98-6.15]) pH ≤ 6.99 (aOR:4.20[95 %CI 1.61-10.91]), five-minute Apgar score ≤ 6 (aOR:3.41[95 %CI 1.49-7.83]) and maternal blood loss (501-1,000 ml: aOR:1.65[95 %CI 1.27-2.16], 1,001-1,500 ml: aOR:3.24[95 %CI 2.24-4.67], 1,501-2,000 ml: aOR:3.94[95 %CI 2.24-6.94] and ≥ 2001 ml: aOR:2.76[95 %CI 1.12-6.82]).

CONCLUSION

This study identified four risk factors for difficult fetal extraction in emergency caesarean section: top-up epidural anesthesia, high maternal BMI, deep fetal descent and anterior placental position. Additionally, difficult fetal extraction was associated with poor neonatal and maternal outcomes.

Risk factors for conversion to general anesthesia for urgent cesarean among women with labor epidural analgesia: A retrospective case-control study

OBJECTIVES

General anesthesia for cesarean is associated with an increased risk of maternal morbidity compared with neuraxial anesthesia. Reducing the rate of general anesthesia for urgent cesarean in women with epidural analgesia may improve maternal outcomes. Our objective was to identify the rate and factors associated with the conversion to general anesthesia for urgent cesarean among women with labor epidural analgesia.

STUDY DESIGN

We performed a retrospective case-control study including singleton-laboring women with epidural analgesia who delivered after 37 gestational weeks by urgent cesarean (Port Royal Maternity unit, 2012-2017). Cases were all women who required conversion from neuraxial analgesia to general anesthesia. Controls were women just before and after each case included. Factors associated with the conversion to general anesthesia were identified using logistic regression analysis.

RESULTS

Among 3,300 laboring women with an epidural analgesia who delivered by urgent cesarean during the study period, 113 (3.4%,) had a conversion to general anesthesia. Factors associated with conversion to general anesthesia were a cervical dilation ≥ 5 cm at the time of epidural placement (aOR 2.55, 95%CI 1.05-6.21), asymmetric sensory blockade (aOR 3.39, 95%CI 1.11-10.36), need for ≥2 rescue top-ups (aOR 2.88, 95%CI 1.29-6.44), and category 1 cesarean (aOR 3.61, 95%CI 1.77-7.33).

CONCLUSION

Among women with labor epidural analgesia, suboptimal analgesia significantly increased the risk for conversion to general anesthesia for urgent cesarean. Epidural placement without delay during labor, regular checks of epidural analgesia efficiency, and epidural replacement in case of inadequate epidural analgesia may decrease the rate of avoidable general anesthesia for urgent cesarean.

Neurologic Complication Due to Crystallization After Drug Interaction Between Alkalized Lidocaine and Ropivacaine: A Case Report and in vitro Study

Background

For pregnant women transferred to emergency cesarean section after receiving epidural labor analgesia, there is still a debate over the effective and safe means of rapidly delivering surgical anesthesia. Alkalized lidocaine is often adopted for fast onset time; however, crystallization of the anesthetic may cause severe neurologic symptoms.

Case Presentation

We report a case of a pregnant woman who underwent emergency cesarean section with satisfied analgesia but experienced severe weakness and paranaesthesia in the lower limb. After excluding lumbar disc herniation, obstetric nerve injury, and anesthesia technique causes by symptoms signs and magnetic resonance imaging, drug-related injury became the most likely cause. Our in vitro testing confirmed the obvious precipitation of additional anesthetic-concentrated ropivacaine (0.5–1%) with pretreated alkalized lidocaine. With trophic neurotherapy, the parturient attained prompt relief of weakness by day four, but delayed recovery of numbness, which lasted for 4 weeks.

Conclusion

To date, this is the first case reporting neurologic complication possibly due to drug crystallization in cesarean section. Our study confirmed the rapid onset of alkalized lidocaine and its safety to pretreated routine labor dose of ropivacaine (0.09%). However, additional anesthetic-concentrated ropivacaine (0.5–1%) to maintain the anesthesia and analgesia level is not suggested.

Choice of local anesthetic in obstetric anesthesiology: literature review and demonstration of our own experience

Regional anesthesia is widely used in obstetric practice, and in many cases is the method of choice. It in­cludes neuroaxial anesthesia (spinal, epidural, combined spinal­epidural, epidural with dura mater puncture), region­al blocks (eg, TAP block, QL block, ESP block, pudendal block, etc.), as well as local infiltration anesthesia, which is used for both anesthesia and postoperative analgesia. The correct choice of local anesthetic, its dose and concentration is of fundamental importance in obstetric anesthesiology, as it is necessary to ensure the highest quality blockade with mini­mal side effects on mother and fetus.

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.

Effect of Low-Dose Intravenous Ketamine on Prevention of Headache After Spinal Anesthesia in Patients Undergoing Elective Cesarean Section: A Double-Blind Clinical Trial Study

Background

Spinal anesthesia is the most commonly used method for elective cesarean section, which is a popular technique due to its simplicity, reliability, and speed to achieve adequate anesthesia. Headache following dura perforation is the most important delayed complication following spinal and epidural anesthesia.

Objectives

To evaluate the impact of low-dose intravenous ketamine in patients undergoing cesarean section under spinal anesthesia on the prevention of dura perforation headache (PDPH).

Methods

This clinical trial study was performed on 64 pregnant women undergoing cesarean section at Vali-e-Asr Hospital. The patients were divided into two groups. In the case group, 0.15 mg/kg body weight ketamine was injected intravenously and in the control group, normal saline was used as the placebo. The incidence of headache and its severity at one, 4, 12, and 24 hours postoperatively, nausea and its severity were also measured and compared. Independent t-test, Mann-Whitney U and chi-square tests were used. A P value < 0.05 was considered statistically significant.

Results

The data revealed that low dose intravenous ketamine significantly decreased patients’ headaches (P = 0.001), the sensation of pruritus (P = 0.009), and the need for analgesic (P = 0.001). Furthermore, the sensation of postoperative nausea was less in the case group. The patients in the case and control groups had no significant difference in terms of hypertension or bradycardia (P = 0.717 and 0.939, respectively).

Conclusions

The injection of ketamine as a premedication in the cesarean section can reduce the severity of postoperative headache in mothers. Therefore, it is recommended to use ketamine as an anti-headache drug in pregnant women.

The maternal and neonatal effects of adding tramadol to 2% lidocaine in epidural anesthesia for cesarean section

Background:

Opioid analgesics are commonly added to epidural local anesthetics to improve analgesia during surgery.

Objectives:

The goal of this study was to evaluate the maternal and neonatal effects of adding different doses of tramadol to 2% lidocaine in the epidural anesthesia for cesarean section.

Patients and Methods:

Ninety pregnant patients who were candidates for cesarean section under epidural anesthesia were randomly categorized into three groups. Group L received 2% lidocaine. In the LT50 and LT100 groups, 50 and 100 mg of tramadol were added to epidural 2% lidocaine. For additional analgesia during surgery, 2% lidocaine through epidural catheter or IV sufentanil were administered. Analgesia after surgery was provided by IV injection of meperidine. Onset and duration of sensory and motor blockades, total drug consumption, neonatal Apgar score, and complications were recorded.

Results:

In the LT100 group, onset of complete sensory and motor blockade at T6 was less than in the two other groups, but the highest level of sensory blockade and two segment regression and duration of motor blockades between the LT50 and LT100 groups were not significantly different, although they were higher and more prolonged than in the L group. Average lidocaine and sufentanil consumption during surgery between the LT50 and LT100 groups were not significantly different but were lower than in the L group. The incidence of maternal complications and neonatal Apgar scores were not significantly different between the three groups. In the LT50 and LT100 groups, the time until the first request for analgesics after surgery was prolonged, and average meperidine consumption was less than in the L group.

Conclusions:

The addition of tramadol to epidural 2% lidocaine offers advantages in cesarean section.

General anesthesia for cesarean delivery at a tertiary care hospital from 2000 to 2005: a retrospective analysis and 10-year update

BACKGROUND

Complications from general anesthesia for cesarean delivery are a leading cause of anesthesia-related mortality. As a consequence, the overall use of general anesthesia in this setting is becoming less common. The impact and implications of this trend are considered in relation to a similar study performed at our institution 10 years ago.

METHODS

The hospital database for all cesarean deliveries performed during six calendar years (January 1, 2000 through December 31, 2005) was reviewed. The medical records of all parturients who received general anesthesia were examined to collect personal details and data pertinent to the indications for cesarean delivery and general anesthesia, mode of airway management and associated anesthetic complications.

RESULTS

Cesarean deliveries accounted for 23.65% to 31.51% of an annual total ranging from 8543 to 10091 deliveries. The percentage of cases performed under general anesthesia ranged from 0.5% to 1%. A perceived lack of time for neuraxial anesthesia accounted for more than half of the general anesthesia cases each year, with maternal factors accounting for 11.1% to 42.9%. Failures of neuraxial techniques accounted for less than 4% of the general anesthesia cases. There was only one case of difficult intubation and no anesthesia-related mortality was recorded.

CONCLUSION

The use of general anesthesia for cesarean delivery is low and declining. These trends may reflect the early and increasing use of neuraxial techniques, particularly in parturients with co-existing morbidities. A significant reduction in exposure of trainees to obstetric general anesthesia has been observed.

Effects of epidural fentanyl on speed and quality of block for emergency cesarean section in extending continuous epidural labor analgesia using ropivacaine and fentanyl

We performed a prospective, randomized, and double-blind study comparing the top-up effects of 2% lidocaine/100 microg fentanyl/epinephrine (n=31) and 2% lidocaine/saline/epinephrine (n=30) when extending an epidural labor analgesia using low-dose ropivacaine and fentanyl. Survival analysis for the sensory blocks to the T4 level showed no statistically significant differences in onset time to T4 between the 2 groups. Onset times (min) to T4-sensory blocks for cold and pinprick were not different between the two groups. However, median maximum sensory level in the lidocaine-fentanyl group (T1 for cold and T2 for pinprick) was significantly higher than that in the lidocaine-saline group (T3 and T4, respectively). The lidocaine-fentanyl group exhibited less visceral pain (6.5% vs. 36.7%), less supplementation of lidocaine (6.5% vs. 43.3%), and less nausea (6.5% vs. 26.7%) compared with the lidocaine-saline group during the intraoperative period. It is concluded that adding fentanyl to 2% lidocaine does not speed up the onset of the block when the onset is tested with cold or sharp pinprick but improves the quality of analgesia with fewer side effects in emergency top-up for cesarean section.

Supplementary oxygen for emergency Caesarean section under regional anaesthesia

BACKGROUND

Controversy still exists if the administration of supplementary oxygen to patients having emergency Caesarean section (CS) under regional anaesthesia is beneficial or potentially harmful. Therefore, in a prospective double-blinded study, we randomized patients having emergency CS under regional anaesthesia to receive either air or 60% oxygen until delivery and compared the effects on fetal oxygenation and lipid-peroxidation in the mother and baby.

METHODS

We recruited 131 women having emergency CS under regional anaesthesia. Either 21% (air group) or 60% oxygen (oxygen group) was administered using a Venturi-type facemask until delivery. We compared the oxygen exposure duration, umbilical arterial (UA) and venous (UV) blood gases and oxygen content, and plasma concentration of 8-isoprostane. Subanalysis was performed according to whether or not fetal compromise was considered present.

RESULTS

Data from 125 patients were analysed. For the oxygen group vs the air group, there were greater values for UA PO(2) [mean 2.2 (SD 0.5) vs 1.9 (0.6) kPa, P=0.01], UA O(2) content [6.6 (2.5) vs 4.9 (2.8) ml dl(-1), P=0.006], UV PO(2) [3.8 (0.8) vs 3.2 (0.8) kPa, P<0.0001], and UV O(2) content [12.9 (3.5) vs 10.4 (3.8) ml dl(-1), P=0.001]. There was no difference between the groups in maternal, UA, or UV 8-isoprostane concentration. Apgar scores and UA pH were similar between the groups. Similar changes were observed regardless of whether fetal compromise was considered present (n=37) or not (n=88).

CONCLUSIONS

Breathing 60% oxygen during emergency CS under regional anaesthesia increased fetal oxygenation with no associated increase in lipid-peroxidation in the mother or fetus.

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.

Epidural lidocaine-bicarbonate-adrenaline vs levobupivacaine for emergency Caesarean section: a randomised controlled trial

Epidural mixtures containing lidocaine with or without additives are commonly used to convert epidural analgesia in labour to anaesthesia for emergency Caesarean section, but direct comparisons with alternative, single agents in this situation are few. In a prospective double-blinded trial, we compared a freshly prepared lidocaine-bicarbonate-adrenaline mixture (final concentrations 1.8%, 0.76% and 1:200,000, respectively) with our standard agent, levobupivacaine 0.5%, for extending epidural blockade for emergency Caesarean section. Using a sequential analysis technique, with data analysed in blocks of 40, women receiving epidural analgesia in labour who required top-up for Caesarean section were randomly assigned to receive 20 ml of epidural solution over 3 min. The first analysis (n = 40) indicated that the study should be stopped, as significant differences were found in our primary outcome data. Median (IQR [range]) times to reach a block to touch to T5 and cold to T4 were, respectively, 7 (6-9 [5-17]) min and 7 (5-8 [4-17]) min for lidocaine-bicarbonate-adrenaline, and 14 (10 -17 [9-31]) min and 11 (9-14 [6-30]) min for levobupivacaine (p = 0.00004 and 0.001, respectively). Pre- and intra-operative supplementation/pain, maternal side-effects and neonatal outcomes (excluding five women who underwent instrumental delivery) were similar between the groups. Intra-operative maternal sedation (scored by the mother on a 10-point scale) was greater with lidocaine-bicarbonate-adrenaline (4.5 (3-8 [1-9])) than with levobupivacaine (3 (1-4 [1-7])), but not significantly so (p = 0.07). We conclude that epidural lidocaine-bicarbonate-adrenaline halves the onset time when extending epidural analgesia for Caesarean section although there is a possibility of increased maternal sedation.

Extending low-dose epidural analgesia in labour for emergency Caesarean section ? a comparison of levobupivacaine with or without fentanyl

Women in labour receiving epidural analgesia with 15 ml bupivacaine 0.1% and 2 microg.ml(-1) fentanyl followed by 10-15-ml top-ups as required, who needed Caesarean section, were randomly allocated to receive 20 ml levobupivacaine 0.5% over 3 min with either 75 microg fentanyl (1.5 ml) or 1.5 ml saline. Further top-ups or inhaled or intravenous supplementation were given for breakthrough pain. Time to onset (loss of cold sensation to T4 and touch sensation to T5 bilaterally), quality of analgesia and side-effects were recorded. The study was stopped after 112 patients had been randomly assigned, due to a unit protocol change, from midwife-administered top-ups to patient-controlled epidural analgesia. Data from 51 patients given fentanyl and 54 given saline were available for analysis. There were no significant differences in onset times or supplementation between the groups, but there was more intra-operative nausea/vomiting with fentanyl (53%) than with saline (18%; p = 0.004). We found no advantage of adding fentanyl to epidural levobupivacaine when extending epidural analgesia in women already receiving epidural fentanyl during labour and there was an increased incidence of intra-operative nausea and vomiting. Power analysis suggested the same conclusion even had the study proceeded to completion.

Risk factors for failure to extend labor epidural analgesia to epidural anesthesia for Cesarean section

OBJECTIVE

To identify parturients at risk of inability to extend labor epidural analgesia in whom alternative methods of anesthesia should be considered for Cesarean section (CS).

METHODS

For 6 months, we prospectively studied women undergoing a CS with a functioning epidural catheter in place from the delivery ward. All parturients received the same epidural protocol: bolus of bupivacaine 0.1% and fentanyl, then bupivacaine 0.1% and fentanyl (2 microg/ml) 10-15 ml/h and an additional 5 ml of bupivacaine 0.125% top-ups according to patient request. Sixteen millilitres of lidocaine 2%, 1 ml of bicarbonate, and 100 microg of fentanyl were given for CS. Failed epidural analgesia was defined as the need to convert to general anesthesia.

RESULTS

Of the 101 parturients studied, 20 (19.8%) required conversion to general anesthesia. In univariate analysis, the likelihood of failed epidural anesthesia was inversely correlated with parturient's age (P = 0.014) and directly correlated with pre-pregnancy weight (P = 0.019), weight at the end of pregnancy (P = 0.003), body mass index (BMI) at the end of pregnancy (P = 0.0004), gestational week (P = 0.008), number of top-ups (P = 0.0004) and visual analog scale (VAS) 2 h before CS (P = 0.03). In multivariate analysis, the number of top-ups in the delivery ward was the best predictor of epidural anesthesia failure (odds ratio 4.39, P = 0.005).

CONCLUSION

Younger, more obese parturients at a higher gestational week, requiring more top-ups during labor, having a higher VAS in the 2 h before CS are at risk of inability to extend labor epidural analgesia to epidural anesthesia for CS.

Risk factors for failure to extend labor epidural analgesia to epidural anesthesia for Cesarean section

AIM

To identify parturients at risk of inability to extend labor epidural analgesia in whom alternative methods of anesthesia should be considered for Cesarean section (CS).

METHODS

For 6 months, we prospectively studied women undergoing CS with a functioning epidural catheter in place from the delivery ward. All parturients received the same epidural protocol: bolus of bupivacaine 0.1% and fentanyl, followed by bupivacaine 0.1% and fentanyl (2 microg/ml) 10-15 ml/h and an additional 5 ml of bupivacaine 0.125% as top-up according to patient request. Sixteen milliliters of lidocaine 2%, 1 ml of bicarbonate and 100 microg of fentanyl were given for CS. Failed epidural analgesia was defined as the need to convert to general anesthesia.

RESULTS

Of the 101 parturients studied, 20 (19.8%) required conversion to general anesthesia. In univariate analysis, the likelihood of failed epidural anesthesia was inversely correlated with parturient age (P = 0.014) and directly correlated with pre-pregnancy weight (P = 0.019), weight at the end of pregnancy (P = 0.003), body mass index at the end of pregnancy (P = 0.0004), gestational week (P = 0.008), number of top-ups (P = 0.0004) and visual analog scale (VAS) score 2 h before CS (P = 0.03). In multivariate analysis, the number of top-ups in the delivery ward was the best predictor of epidural anesthesia failure (odds ratio, 4.39; P = 0.005).

CONCLUSION

Younger, more obese parturients at a higher gestational week, requiring more top-ups during labor and having a higher VAS score in the 2 h before CS are at risk for inability to extend labor epidural analgesia to epidural anesthesia for CS.

A randomised comparison of 0.5% bupivacaine with a lidocaine/epinephrine/fentanyl mixture for epidural top-up for emergency caesarean section after "low dose" epidural for labour

BACKGROUND

When extending a fentanyl-containing, low-dose labour epidural for emergency caesarean section it has been shown that there is no difference in time to surgical readiness between plain bupivacaine 0.5% and mixtures of lidocaine/epinephrine or lidocaine/bupivacaine/epinephrine. However, it is not known whether adding fentanyl to the lidocaine/epinephrine mixture would increase speed of onset or improve the efficacy of the mixture when topping up for an emergency caesarean section.

METHODS

In a prospective, single blind study we compared plain 0.5% bupivacaine with a lidocaine/epinephrine/fentanyl mixture for extending previous low-dose epidural analgesia for emergency caesarean section in 68 patients.

RESULTS

There was a significantly longer median preparation time for the mixture than for the single drug (3.0 v 1.25 min: P < 0.0005). The median onset time for block of T7 to touch from the start of the top-up was 13.8 min for the mixture and 17.5 min for plain bupivacaine. This difference was not statistically significant and was offset by the longer preparation time. No general anaesthetics were required for poor blocks and the need for other intraoperative supplementation was not significantly different between the groups (bupivacaine 5/34, lidocaine mixture 2/26).

CONCLUSIONS

The use of a lidocaine/epinephrine/fentanyl mixture conferred no clear statistically significant benefit over the use of plain 0.5% bupivacaine when used to extend fentanyl containing low-dose labour epidural analgesia for emergency caesarean section, but the lidocaine solution is cheaper and less toxic than the alternatives.

Glass recycling in the labour suite is environmentally sound and economical

BACKGROUND

Glass bottles are used for the storage of local anaesthetics in the US and are recyclable. Recycling would result in hospital solid waste reduction.

METHODS

The members of the Department of Anaesthesia were surveyed to determine where these local anaesthetic bottles were disposed of. From November 2002 to April 2003, glass bottles used on the labour and delivery suite were saved for recycling. The number of bottles and the weight recycled were recorded. The number of procedures involving anaesthesia were also recorded during this time period.

RESULTS

Residents dispose of the local anaesthetic bottle in the sharps container while consultants dispose of them in the trash (P<0.05). Both means of disposal are not recycled in the US. The average amount of glass recycled per month was 19.37 (3.15) kg. Our hospital pays $0.46/kg (0.26 UK pound/kg) for sharps disposal. By not disposing of the glass in the sharps container, the average savings per month was $8.95 (1.45) (5.15 UK pounds (0.84)).

CONCLUSION

The recycling of glass is good for the environment through waste reduction and results in small savings to the hospital.

Regional Anaesthesia in Pre-eclampsia

Pre-eclampsia is a multisystemic disorder that is characterised by endothelial cell dysfunction as a consequence of abnormal genetic and immunological mechanisms. Despite active research for years, the exact aetiology of this potentially fatal disorder remains unknown. Although understanding of the pathophysiology of pre-eclampsia has improved, management has not changed significantly over the years. Anaesthetic management of these patients remains a challenge. Although general anaesthesia can be used safely in pre-eclamptic women, it is fraught with greater maternal morbidity and mortality. Currently, the safety of regional anaesthesia techniques is well established and they can provide better obstetrical outcome when chosen properly. Thus, regional anaesthesia is extensively used for the management of pain and labour in women with pre-eclampsia. This article highlights the advantages and disadvantages of regional anaesthetic techniques including epidural, spinal and combined spinal-epidural analgesia, used as a part of the management of pre-eclampsia. The problems associated with general anaesthesia and controversies in relation to obstetric regional anaesthesia are discussed.

Anaesthesia for non-scheduled caesarean delivery

In many countries there has been an increase in the number of women who deliver by caesarean section. This article reviews anaesthetic management of non-scheduled caesarean section. The choice of anaesthetic technique (regional anaesthesia versus general anaesthesia) is discussed and highlighted particularly from the viewpoint of urgency of operative delivery. A multidisciplinary approach is mandatory especially in emergency cases to prevent morbidity and mortality in mothers and neonates.