Dorsal column function after epidural and spinal blockade: implications for the safety of walking following low-dose regional analgesia for labour

Walking after regional blockade for labour using low-dose combinations of bupivacaine and fentanyl is possible due to the maintenance of lower limb motor power. In order to investigate concerns that dorsal column function, important in maintaining balance, is impaired after such techniques, clinical assessment of lower limb proprioception and vibration sense was evaluated in parturients after either low-dose epidural ( n  = 30) or spinal blockade ( n  = 30) for labour analgesia and compared with spinal anaesthesia ( n  = 30) for elective Caesarean section using a larger total dose of local anaesthetic. Of the patients receiving low-dose regional labour analgesia 7% ( n  = 4) had abnormal dorsal column function compared with 97% ( n  = 29) receiving spinal anaesthesia for Caesarean section (p < 0.001). All patients in the Caesarean section group developed lower limb motor weakness, compared with only 10% ( n  = 6) in the low-dose groups (p < 0.001). There were no significant differences between the low-dose groups with respect to sensory block, motor block or dorsal column function. Overall, 90% of patients receiving low-dose bupivacaine/fentanyl regional labour analgesia had both normal lower limb motor power and dorsal column function. Assessment of these parameters is recommended before allowing patients to walk after low-dose regional techniques for labour.     

Cathétérisation accidentelle de l'espace sous-dural extra-arachnoïdien lors d'une analgésie péridurale en obstétrique

The authors describe a case of accidental catheterization of the subdural extra-arachnoid space during epidural analgesia for labour. The epidural catheter had been inserted at the L3–L4 interspace without any problem. A severe hypotension occurred 90 min after the onset of analgesia. A T4 upper sensory level was associated with a complete motor blockade. Total spinal anaesthesia was suspected but ruled out because of delayed onset of analgesia. Extensive epidural anaesthesia was also eliminated as the local anaesthetic dose (15 mL of bupivacaine 0.125 %) was not excessive for this patient. After delivery, a water-soluble contrast medium (10 mL of Omnipaque® 180) was injected through the catheter and subsequent radiograph of spine showed subdural spread of the contrast medium. This complication might occur more frequently than usually thought and may be life-threatening. Anaesthetic management is discussed in the case of Caesarean section during labour.     

Emergency Caesarean section: best practice

Good multidisciplinary communication is crucial to the safe management of women requiring non-elective Caesarean section. Anaesthetists should participate actively in resuscitation of the fetus in utero; relief of aortocaval compression is paramount. Epidural top-up with levobupivacaine 0.5% is the anaesthetic of choice for women who have been receiving labour epidural analgesia. If epidural top-up fails to provide bilateral light touch anaesthesia from S5 - T5, a combined spinal-epidural technique with small intrathecal dose of local anaesthetic is a useful approach. Pre-eclampsia is not a contra-indication to single-shot spinal anaesthesia, which is the technique of choice for most women presenting for Caesarean section without an epidural catheter in situ. Induction and maintenance doses of drugs for general anaesthesia should not be reduced in the belief that the baby will be harmed. Early postoperative observations are geared towards the detection of overt or covert haemorrhage.     

Surgical anaesthesia for Caesarean section with a subdural catheter

Purpose

This case report describes a radiologically proven subdural catheter placed in a term parturient, which consistently performed as an epidural catheter for both labour analgesia as well as surgical anaesthesia.

Clinical features

The patient was a 26-yr-old, 52.7 kg, 140 cm healthy woman with a 39 wk intrauterine pregnancy. At initiation of epidural blockade, and for many hours throughout labour, an appropriate volume and concentration of local anaesthetic achieved an appropriate analgesic sensory level (10 ml bupivacaine 0.25%, bilateral T₁₀ sensory level). However, for Caesarean section, while an appropriate volume and concentration of local anaesthetic achieved an appropriate surgical anaesthetic sensory level (15 ml bupivacaine 0.5%, bilateral T₄ sensory level), there was no demonstrable motor blockade (0 on the Bromage scale). The Caesarean section was performed without incident, and without the need for supplemental intravenous opioids or anxiolytics.

Conclusion

We report the case to question the commonly held beliefs of subdural catheter presentation. We questioned the catheter position, and proved its subdural placement, only after larger volumes of higher concentration local anaesthetic did not achieve expected goals. It is possible that a high percentage of epidural catheters may be subdural, unbeknownst to the practitioner.     

Obstetrical anaesthesia and porphyrias

Acute hepatic porphyrias are genetic diseases, characterized by acute neurological symptoms, sometimes fatal, triggered by different factors, in particular by many anaesthetic drugs, and also by pregnancy. We report here the experience of three porphyric patients'deliveries, allowing us to consider a proposition of management in this context. After discussion between anaesthesiologist, obstetrician and porphyria specialist, two types of management of such patients can be foresee. Asymptomatic patients, or in long remission, can benefit from locoregional anesthesia techniques with bupivacaine for both labour analgesia and Caesarean section. Spinal anaesthesia is then the technique of choice, allowing using smaller quantity of local anaesthetic than epidural anaesthesia. For symptomatic patients, or in crisis, we have rather choose intravenous narcotics for labour analgesia, and general anaesthesia for Caesarean section. The hypnotic agent of choice for both induction and maintenance of such anaesthesia is then propofol.     

Epidural anaesthesia for labour and Caesarean section in a parturient with a single ventricle and transposition of the great arteries

We describe a case of a 29-year-old parturient with a single ventricle and transposition of the great arteries who had lumbar epidural analgesia/anaesthesia with a local anaesthetic for labour, emergency Caesarean section and postoperative pain. Her outcome and that of her baby was successful. The anaesthetic techniques used in other parturients with similar congenital cardiac anomalies are reviewed.     

Effects of volume and concentration of lidocaine on epidural anaesthesia in pregnant females

BACKGROUND AND OBJECTIVE: The effects of altering the concentration of a local anaesthetic on the development of epidural anaesthesia in pregnant females are unclear. We compared the anaesthetic effects of a constant dose of two different concentrations of epidural lidocaine for Caesarean section. METHODS: After Institutional Review Board approval and informed consent, patients undergoing elective Caesarean section were randomized to receive either lidocaine 1% 30 mL (+epinephrine 5 microg mL(-1)) or lidocaine 2% 15 mL (+epinephrine 5 microg mL(-1)) (n = 20 each) for epidural anaesthesia at the L1-L2 interspace. The spread of the sensory block to pinprick and the degree of motor block (modified Bromage scale) were measured at 5, 10, 15, 20 and 30 min after injection. RESULTS: No significant differences in the progression of analgesia and motor block were observed at any time between 1 and 2% lidocaine. The maximum cephalad spread was observed 30 min after injection; the median was at T4 (range T3-T5) and at T4 (range T3-T6) for lidocaine 1 and 2%, respectively. CONCLUSIONS: The same doses but different volumes of lidocaine 1 and 2% produced comparable anaesthetic effects in pregnant females. The effects of epidural anaesthesia depend primarily on the total dose of the local anaesthetic.     

A survey of antenatal and peripartum provision of information on analgesia and anaesthesia

Pregnant women should receive information about what they might expect to experience during their delivery. Despite this, research shows many women are inadequately prepared for anaesthetic interventions during labour. We surveyed 903 postnatal women across 28 Greater London hospitals about: the analgesic and anaesthetic information that they recalled receiving during pregnancy and delivery; their confidence to make decisions on analgesia; and their satisfaction with the analgesia used. Wide variation was observed between hospitals. Overall, 67 of 749 (9.0%) women recalled receiving antenatal information covering all aspects of labour analgesia, and 108 of 889 (12.1%) covering anaesthesia for caesarean section. Regarding intrapartum information, 256 of 415 (61.7%) respondents recalled receiving thorough information before epidural insertion for labour analgesia, and 102 of 370 (27.6%) before anaesthesia for caesarean section. We found that 620 of 903 (68.7%) women felt well enough informed to be confident in their analgesic choices, and 675 of 903 (74.8%) stated that their analgesia was as expected or better. Receiving information verbally, regardless of provider, was the factor most strongly associated with respondents recalling receiving full information: odds ratio (95%CI) for labour analgesia 20.66 (8.98–47.53; p < 0.0001); epidural top-up for caesarean section 5.93 (1.57–22.35; p = 0.01); and general anaesthesia for caesarean section 12.39 (2.18–70.42; p = 0.01). A large proportion of respondents did not recall being fully informed before an anaesthetic intervention. Collaboration with current antenatal service providers, both in promoting information delivery and providing resources to assist with delivery, could improve the quality of information offered and women's retention of that information.     

Anesthesia for emergency cesarean section after uterine rupture associated with recent fracture of the cervical spine

General anaesthesia with intubation is preferable for emergency Caesarean section, whilst epidural anaesthesia should be reserved for elective Caesarean section. The case of a patient who required emergency Caesarean section following uterine rupture is discussed. The management was complicated by a cervical spine injury which had occurred four months previously. Because an epidural catheter had already been inserted at an early stage of labour, this was the anaesthetic technique chosen for the emergency section. This avoided tracheal intubation and the possibility of worsening the cervical fracture. The end result was satisfactory, both for the mother and the child.     

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

In a randomised, double-blind study, we investigated rapid extension of epidural analgesia to surgical anaesthesia for emergency Caesarean section. Parturients receiving epidural analgesia in labour who subsequently required Caesarean section were given a test dose of 3 ml lidocaine 2% with epinephrine 1 : 200 000, followed 3 min later by 12 ml lidocaine 2% with epinephrine 1 : 200 000 and fentanyl 75 microg, to which was added 1.2 ml sodium bicarbonate 8.4% (bicarbonate group; n = 20) or saline (saline group; n = 20). Mean (SD [range]) time to surgical anaesthesia was less in the bicarbonate group (5.2 (1.5) [2-8] min) than the saline group (9.7 (1.6) [6-12] min; mean difference 4.5 min (95% CI 3.5-5.5) min; p < 0.001). Maternal side-effects and neonatal outcome were similar between groups. We conclude that pH-adjusted lidocaine 2% with epinephrine and fentanyl is effective for rapidly establishing surgical anaesthesia in patients with a functioning epidural catheter for labour who require emergency Caesarean section.     

Obstetric regional blocks for women with multiple sclerosis: a survey of UK experience

BACKGROUND: There has been a reluctance to use regional blocks for women with multiple sclerosis as effects on the course of the disease are unclear. We assessed the views of UK consultant obstetric anaesthetists regarding management of women with multiple sclerosis. METHODS: Following Obstetric Anaesthetists' Association approval a questionnaire was sent to UK consultant members. Opinions were sought on antenatal assessment, labour analgesia, anaesthesia for elective and emergency caesarean section, and modification in technique for those with multiple sclerosis. Enquiries were made of postnatal problems ascribed to regional blocks. RESULTS: Of the 592 replies analysed, 91% of respondents had seen fewer than 10 cases of multiple sclerosis in the past 10 years. Antenatal assessment was recommended by many with postnatal relapse most commonly discussed (64%). Many highlighted the need for informed consent and minimising local anaesthetic dose. For labour analgesia 79% would perform a regional block; a further 20% would do so in certain circumstances. For elective caesarean section, epidural rather than spinal anaesthesia was preferred by 4%; 2% would not use a regional block, preferring general anaesthesia. For emergency caesarean section with time only for single-shot spinal, 3% would give a general anaesthetic. Deterioration of symptoms after delivery were reported by 20% with 3% attributing symptoms such as prolonged block, leg weakness, bladder dysfunction and postnatal relapse to regional blocks. CONCLUSION: Most UK anaesthetists would perform regional blocks for labour and caesarean section in multiple sclerosis, although the experience of each anaesthetist is limited. Many emphasised the need for thorough pre-assessment and informed consent.     

Epidural anaesthesia for caesarean section in an achondroplastic dwarf

This report describes the anaesthetic management of an 18-yr-old achondroplastic dwarf who presented for elective Caesarean section. Epidural anaesthesia was performed without technical difficulty using 8 ml carbonated lidocaine 2% with epinephrine 1:200,000. Although the skeletal abnormalities of achondroplasia have been cited as contraindications to the use of epidural anaesthesia, clinical experience does not support this contention. Previous reports have described technical difficulties in these patients, such as dural puncture and inability to advance the catheter into the epidural space, but no serious complications resulted and epidural anaesthesia was successful on subsequent attempts. The existing literature on the anaesthetic management of achondroplasia for Caesarean section is reviewed and considerations are presented concerning the choice of local anaesthetic, the epidural test dose, and dose titration.     

The influence of anaesthetic techniques and type of delivery on peripartum serum interleukin-6 concentrations

Background: Interleukin-6 is a pleiotropic cytokine with a wide range of physiological activities. It plays an important role in the immuno-neuro-humoral axis during stress and surgery.
Methods: Serum interleukin-6 in parturients was measured on hospital admission, immediately after birth and 12 and 24 hours later. All parturients had uncomplicated pregnancies, and delivered vaginally without (n=31) or with (n=20) epidural analgesia, or underwent Caesarean section under epidural (n=20) or general (n=10) anaesthesia.
Results: Serum interleukin-6 assayed immediately following Caesarean section was low, but peaked 12 hours later, irrespective of the anaesthetic technique or other foetomaternal characteristics. Patients who delivered vaginally showed the highest interleukin-6 levels immediately after delivery. These were positively correlated with serum interleukin-6 on admission and duration of labour. Serum interleukin-6 was significantly higher in parturients who had epidural analgesia, and was significantly lower in those receiving intravaginal prostaglandins compared to those without prostaglandins.
Conclusion: The interleukin-6 response after Caesarean section can be explained by a generalized acute phase response to surgery, with no anaesthetic, maternal or neonatal interference. The rapid increase in peripartum serum interleukin-6 levels after vaginal delivery reflects, in part, cervical ripening or labour, their physiological triggers and psychological or physical stress. Regional anaesthesia, duration of labour and exogenous prostaglandin administration can modulate the peripartum interleukin-6 response and subsequently the physiological effects of this cytokine.     

Practice of epidural analgesia for labour pain: a German survey.

Epidural analgesia is one of the preferred methods of analgesia for labour. The aim of the present survey was to evaluate current practice in obstetric analgesia in departments of anaesthesia and to make a comparison with former surveys from Germany and other countries. Questionnaires on the practice of pain relief, especially epidural analgesia, during labour and delivery were sent to 1178 anaesthetic departments in Germany in the second half of 1996. Five hundred and thirty-two completed replies were received, which represent 46.9% of all German obstetric units. The majority of the departments of anaesthesia practising epidural analgesia have an epidural rate of less than 10% and 10.2% of the departments do not offer this method to their parturients. In 86.8% of all units performing epidural analgesia, the epidural catheter is placed by an anaesthetist. Only 6.5% of the units provide a 24-h epidural service which is exclusively assigned to labour and delivery. In 77.8% of the units, this service is not exclusively assigned to obstetrics, but also to other duties. Of the obstetric units offering epidural analgesia, 14.7% have no epidural service at night. Plain local anaesthetics for epidural analgesia are used by 55.9% of the departments, a combination of local anaesthetics with epidural opioids by 28.7%. Epidural analgesia is predominantly (82.2%) maintained by intermittent bolus administration. Although the rate of epidural analgesia increased during recent decades, this method is not offered to all parturients. Further improvements in the use of epidural analgesia for labour seem to be necessary.     

Obstetrical anaesthesia in Ontario

The purpose of this study was to determine the availability of regional anaesthesia for Caesarean section, of epidural opioids and patient-controlled analgesia after Caesarean section, and of epidural and other forms of analgesia in labour. A mail survey was sent to the “Head Nurse, Department of Obstetrics” at each of the 142 hospitals in Ontario with designated obstetric beds. Responses were obtained from 100% of hospitals. For Caesarean Section, general anaesthesia was used in all hospitals, and was the only option in seven. Epidural anaesthesia was used in 93% of hospitals, and spinal anaesthesia in 48%. Postoperatively, patient-controlled analgesia was used in 31% of hospitals and spinal opioids in 28%. In 66 hospitals, im or iv opioids were the only types of analgesia available. For analgesia in labour, im or iv opioids were used in 96% of hospitals, nitrous oxide was used in 75%, epidural analgesia in 75%, transcutaneous electrical nerve stimulation in 52% and patient-controlled analgesia in 10%. The overall epidural rate was 38%. Although the average rate in the 73 hospitals with fewer than 500 births per year was only 6% 14 large hospitals had an epidural rate of 60% or higher. It is concluded that regional techniques for peripartum analgesia have been widely accepted. Analgesia after Caesarean section could be improved. Epidural analgesia should be more widely available, especially in the many small hospitals in Ontario.     

Spinal anaesthesia for obstetrics

For a long time, epidural anaesthesia has been considered the method of choice for Caesarean delivery. The increased incidence of hypotension by the rapid onset of sympathetic blockade under spinal anaesthesia has been associated with a decline in uteroplacental blood flow and significant fetal acidosis, which may compromise neonatal well-being. Nevertheless, a decrease in fetal pH has not been shown to reduce neonatal Apgar or neurobehavioural assessment scores. Maternal blood pressure can be preserved with little side effects with low doses of vasopressors. On the other hand, spinal anaesthesia conveys significant advantages over epidural anaesthesia such as the simplicity of its use and the speed of onset, which allows neuraxial anaesthesia in urgent Caesarean sections and thus reduces the necessity for general anaesthesia. The small doses of local anaesthetics required to perform spinal anaesthesia reduce the risks of systemic toxicity to zero. Spinal anaesthesia is now considered the method of choice for urgent Caesarean section. The use of intrathecal opioids has profoundly changed the quality of spinal anaesthesia, with improved analgesia, a reduction in local anaesthetic requirements and shorter duration of motor blockade. Preliminary studies indicate that spinal anaesthesia may be safely performed in patients with severe pre-eclampsia, in whom spinal anaesthesia was previously considered contraindicated.     

Spinal anaesthesia for caesarean section following epidural analgesia in labour: a relative contraindication

Three cases are described in which epidural analgesia was performed during labour using an infusion of bupivacaine 0.125-0.25%. When, in all 3 cases, caesarean section was required for failure to progress, hyperbaric bupivacaine was given in doses of 10 mg, 12.5 mg and 15 mg respectively. Within 2-4 min all 3 patients had a high block, complained of difficulty in breathing and subsequently developed apnoea. The trachea was intubated after administration of thiopentone and succinylcholine and the operation continued. Cardiovascular support was provided by the administration of ephedrine injected intermittently intravenously. The spinal block receded and the patients were able to return to the ward without any further complications. All three mothers remain in good health and do not regret having had spinal anaesthesia for caesarean section. In contrast to previously reported cases of high spinal anaesthesia following unsuccessful epidural anaesthesia for caesarean section, this report describes 3 cases of high spinal following the administration of spinal anaesthesia upon an ongoing epidural infusion of local anaesthetic during labour. As no guidelines are available as to the recommended dose of spinal anaesthetic under such circumstances and, in view of the several case reports describing a similar complication under different circumstances, we suggest that spinal anaesthesia is contraindicated upon ongoing epidural analgesia or following a failed epidural.     

Challenges that opioid-dependent women present to the obstetric anaesthetist

A retrospective casenote review was performed to identify anaesthetic challenges relevant to the opioid-dependent obstetric population. Medical records showed that of the 7,449 deliveries during a 24 month period, 85 women (1.1%) were taking regular opioids such as methadone and/or heroin. Of these 67 (79%) received anaesthetic services, ten of whom (11.7%) were referred antenatally. Forty opioid-dependent women (47%) received epidural analgesia in labour compared with the overall hospital rate of 38%. Twenty-three women (27%) delivered by caesarean section: five received general anaesthesia, five combined spinal anaesthesia, five spinal anaesthesia and eight epidural anaesthesia. Twenty opioid-dependent women (23.5%) had documented problems related to labour analgesia and 17 (74%) had problems with analgesia after caesarean section. A variety of postoperative analgesia methods were administered in addition to maintenance methadone. Fourteen patients (16.5%) had difficult intravenous access and seven "arrest" calls were documented. One anaesthetist was exposed to hepatitis C. This review demonstrates the demands placed on obstetric anaesthetic services by opioid-dependent women. Early antenatal referral for anaesthetic review is recommended.     

A comparison between epidural anaesthesia using alkalinized solution and spinal (combined spinal/epidural) anaesthesia for elective caesarean section

In a double-blind investigation, 40 women undergoing elective lower segment caesarean section were randomly divided into two groups. Group I (n = 20) received spinal anaesthesia with 2.0 ml hyperbaric 0.5% bupivacaine using a single space combined spinal epidural technique. Group II (n = 20) received epidural anaesthesia with a local anaesthetic mixture consisting of 0.5% bupivacaine plain 10 ml and 2% lignocaine plain 10 ml to which was added 0.1 ml of adrenaline 1 in 1000 and 2 ml of 8.4% sodium bicarbonate. The mean onset times of sensory block to T4 and grade 3 motor blockade were 7.9 min and 9.5 min respectively in the spinal group, compared to 13.1 min and 16.3 min in the epidural group. These differences were both significant (P < 0.05). There was no difference between the two groups in the quality of analgesia or the incidence of hypotension and nausea. The relatively rapid onset of the pH adjusted epidural solution may provide an attractive alternative to spinal anaesthesia. Moreover, this study underlines the important role of pH adjusted epidural solutions in parturients progressing to emergency caesarean section with epidural catheters previously inserted for labour analgesia.     

A survey of the practice of thoracic epidural analgesia in the United Kingdom

A postal survey of the practice of thoracic epidural analgesia was sent to 275 hospitals in the United Kingdom. Responses were received from 70% of hospitals. Informed consent is rarely adequately obtained, with only 28% of respondents mentioning even the most common complications. Epidural cannulation is most often (60%) performed following induction of general anaesthesia, rather than in the awake patient. A test dose of local anaesthetic without adrenaline is usual. Neither aspirin nor low-dose heparin are considered a contraindication. The majority of respondents used a combination of bupivacaine with fentanyl (51%) or diamorphine (40%), usually administered by continuous infusion. Drugs were frequently prepared and adjusted by anaesthetic staff. The majority of epidurals (63%) are nursed in intensive care units postoperatively. Properly funded pain management teams, at present unusual, would facilitate ward-based epidural management and release intensive care resource. A central register of epidural complications is required to provide valuable evidence for the optimum practice of thoracic epidural analgesia.