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.     

Combined epidural/spinal anaesthesia for Caesarean section

An evaluation of a 30 gauge spinal needle in a combined epidural/spinal anaesthetic technique for Caesarean section revealed a 25% failure rate of the spinal element. In this unit, no more than 4% of spinal anaesthetics might be expected to fail. One of the reasons for the higher failure rate was that, when using the Tuohy needle as an introducer, the dura was not identified. This prompted us to compare the 'through-the-Tuohy' or needle within needle approach for combined epidural/spinal anaesthesia, with a technique that involved siting the epidural and spinal sequentially in separate spaces. One hundred women requiring elective Caesarean section under spinal anaesthesia were randomised into single or double space groups. The technique failed in 16% of through-the-needle cases, and in 4% of sequential sitings. Combined spinal/epidural anaesthesia for Caesarean section is more successful if each procedure is performed using separate spaces.     

Double-space combined spinal-epidural technique for elective caesarean section: a review of 10 years’ experience in a UK teaching maternity unit

BackgroundIn obstetric practice use of a regional technique with a low failure rate minimises the need to convert to general anaesthesia (GA). Previous studies have suggested that combined spinal-epidural anaesthesia (CSE) has a lower GA conversion rate than spinal or epidural anaesthesia alone. In addition, a double-space CSE may be associated with fewer failures than the needle-through-needle technique. However, whether this has an effect on GA conversion rate is unknown. We aimed to review our practice of the double-space CSE technique for elective caesarean section.MethodsData from 3519 elective caesarean sections performed between 1999 and 2008 using the double-space CSE technique were collected retrospectively from the electronic database, original case records and annual reviews collated by the Department of Obstetric Anaesthesia, St James’s University Hospital, Leeds. Complications such as conversion to GA, accidental dural puncture (ADP), post-dural-puncture headache (PDPH) and blood patching were specifically reviewed.ResultsThe GA conversion rate in our unit was 0.23% (1:440). The ADP rate was 0.7% (1:141) with a 52% incidence of severe PDPH. The overall need for blood patching was 0.4% (1:251). One in five epidurals was supplemented during caesarean section.ConclusionCompared to previously published work using spinal or needle-through-needle CSE anaesthesia we have found a lower GA conversion rate in our unit using the double-space CSE technique for elective caesarean section.     

A survey of anaesthetic techniques used for caesarean section in the UK in 1997

A prospective survey of anaesthesia for caesarean section was performed for the year 1 January to 31 December, 1997. Two hundred and fifty maternity hospitals were sent questionnaires from which 129 responses were obtained. The data provided information on anaesthesia for 60 455 caesarean sections. Overall 78% of sections were performed with regional anaesthesia: 47% single shot spinal; 22% epidural; 9% combined spinal epidural (CSE); 22% general anaesthesia. For elective caesarean sections (39% of all sections) regional anaesthesia was used for 87% of cases: 68% single shot spinal; 3% epidural; 15% CSE; 13% general anaesthesia. For emergency procedures regional anaesthesia was used for 72% of cases: 34% single shot spinal; 34% epidural; 4% CSE; 28% general anaesthesia. There was a wide range of regional anaesthesia use among the units, varying from an overall rate of 95% at one extreme to 41% at the other. Similarly, there was a wide range of conversion of regional anaesthesia to general anaesthesia, varying from 0% to 88%. Overall, 10.6% of the general anaesthetics were the result of regional to general anaesthesia conversion.     

Epidural and spinal (subarachnoid) anaesthesia for Caesarean section

Regional anaesthesia for Caesarean section is increasing in popularity — a trend encouraged by obstetric anaesthetists because of its greater safety and the emotional benefits tomother and baby. Such anaesthesia is easier to provide for elective cases, but even in the case of many emergency or semi-emergency Caesarean sections there may be time to extend an epidural already in use, or to use spinal anaesthesia.The reason for the difficulty in providing effective epidural anaesthesia in some cases has been clarified with the identification of variable bands and septa in the epidural space. Spinal block gives more reliable anaesthesia but carries a higher risk of hypotension so that monitoring to detect, and measures to prevent it must be particularly rigorous.Two new developments which are likely to play a part in improving regional anaesthesia for Caesarean section and post-operative pain relief are continuous spinal and combined spinal-epidural techniques. In the case of the former, particular interest is being focused on very fine microcatheters, but the incidence of post-spinal headache with larger catheters is also being reassessed. The combined technique gives the speed of onset and reliability of the spinal block with the flexibility of analgesia provided by the epidural catheter, as well as the advantage of the Tuohy needle acting as guide for the very fine spinal needles.     

Failure of regional blockade for caesarean section

This four-year retrospective study examined the quality of regional blockade for caesarean section. For patients having spinal anaesthesia, data were available on requirement for analgesic supplementation or conversion to general anaesthesia. In those having epidural anaesthesia, data were available only for conversion to general anaesthesia. A total of 1644 patients due to have caesarean section under spinal anaesthesia were studied and of these, 48 (2.9%) required general anaesthesia at some stage. Of the 1610 patients in whom a caesarean section was started under spinal, 12 (0.75%) received general anaesthesia while 175 (10.9%) required some analgesic supplementation. Of the 827 patients in whom epidural analgesia was in progress for labour and a decision was made to proceed to caesarean section, a total of 87 patients (10.5%) needed general anaesthesia. Of those (763) in whom caesarean section was started under epidural, only 17 (2.2%) were given general anaesthesia because of intra-operative pain. Although these results may fall short of best practice, they may enable the anaesthetist to give more accurate information to patients so that better informed consent can be obtained.     

Low-dose combined spinal-epidural anaesthesia vs. conventional epidural anaesthesia for Caesarean section in pre-eclampsia: a retrospective analysis

BACKGROUND AND OBJECTIVE: Epidural anaesthesia is the preferred technique of anaesthesia for Caesarean section in pre-eclampsia. Spinal anaesthesia is considered by some as a safe and effective alternative, which is especially useful in emergency situations. Combined spinal-epidural anaesthesia, using low doses of local anaesthetics with opioids, is effective and reduces the incidence of hypotension in normal pregnancy. We performed a retrospective chart analysis to evaluate the effects of combined spinal-epidural anaesthesia on maternal haemodynamics and fetal outcome compared to conventional epidural anaesthesia. METHODS: A retrospective anaesthesia chart analysis of all pre-eclamptic patients who underwent Caesarean section over a 4 yr period was performed. Patient characteristic, obstetric, haemodynamic, fetal and neonatal data were gathered and analysed according to the anaesthetic technique used. RESULTS: Seventy-seven pre-eclamptic parturients undergoing Caesarean section were identified (26 women were severely pre-eclamptic and 51 demonstrated mild pre-eclampsia). Epidural anaesthesia was performed in 62 patients and combined spinal-epidural anaesthesia was performed in 15. No differences in patient characteristic and obstetric data were noted. Highest mean arterial pressure prior to anaesthesia was comparable between the groups (epidural: 106 +/- 12 vs. combined spinal-epidural anaesthesia: 109 +/- 18 mmHg) as well as the lowest recorded mean arterial pressure following anaesthesia (epidural: 93 +/- 13 vs. combined spinal-epidural anaesthesia: 98 +/- 17 mmHg). In the combined spinal-epidural anaesthesia group more ephedrine was used compared to the epidural group (14.6 +/- 4.4 vs. 3.6 +/- 4.6 mg, P < 0.05). However, more lactated Ringer's was used in the epidural group. Umbilical artery pH was lower in the epidural group (7.26 +/- 0.01 vs. 7.29 +/- 0.02, P < 0.05). Similar results were noted in 26 severely pre-eclamptic patients. Seven women underwent combined spinal-epidural anaesthesia and 19 underwent epidural anaesthesia in the severely pre-eclamptic group. Also more ephedrine was used in the combined spinal-epidural anaesthesia group. A tendency towards a lower umbilical artery pH was observed in the epidural group but this difference did not reach statistical significance. CONCLUSIONS: Combined spinal-epidural anaesthesia appears to be safe as anaesthetic technique for pre-eclampsia and severe pre-eclampsia. However, it is important to consider the retrospective design of the study and the large number of epidural anaesthetics performed.     

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.     

An evaluation of a 30-gauge needle for spinal anaesthesia for Caesarean section

A 30-gauge spinal needle was evaluated for Caesarean section, using a combined epidural/spinal technique, in 50 mothers. Spinal anaesthesia failed in six mothers and was inadequate in another six. General anaesthesia was required on one occasion. A 25% overall failure rate suggests that a 30-gauge needle is not a practical proposition for routine clinical practice.     

Inadequate neuraxial anaesthesia in patients undergoing elective caesarean section: a systematic review

Neuraxial anaesthesia is widely utilised for elective caesarean section, but the prevalence of inadequate intra-operative anaesthesia is unclear. We aimed to determine the prevalence of inadequate neuraxial anaesthesia for elective caesarean section; prevalence of conversion from neuraxial anaesthesia to general anaesthesia following inadequate neuraxial anaesthesia; and the effect of mode of anaesthesia. We searched studies reporting inadequate neuraxial anaesthesia that used ≥ ED95 doses (effective dose in 95% of the population) of neuraxial local anaesthetic agents. Our primary outcome was the prevalence of inadequate neuraxial anaesthesia, defined as the need to convert to general anaesthesia; the need to repeat or abandon a planned primary neuraxial technique following incision; unplanned administration of intra-operative analgesia (excluding sedatives); or unplanned epidural drug supplementation. Fifty-four randomised controlled trials were included (3497 patients). The overall prevalence of requirement for supplemental analgesia or anaesthesia was 14.6% (95%CI 13.3–15.9%); 510 out of 3497 patients. The prevalence of general anaesthesia conversion was 2 out of 3497 patients (0.06% (95%CI 0.0–0.2%)). Spinal/combined spinal–epidural anaesthesia was associated with a lower overall prevalence of inadequate neuraxial anaesthesia than epidural anaesthesia (10.2% (95%CI 9.0–11.4%), 278 out of 2732 patients vs. 30.3% (95%CI 26.5–34.5%), 232 out of 765 patients). Further studies are needed to identify risk factors, optimise detection and management strategies and to determine long-term effects of inadequate neuraxial anaesthesia.     

Umfrage zur aktuellen Situation der Regionalanästhesie im deutschsprachigen Raum

The practice of regional anaesthesia in German speaking countries was investigated by a survey. The last part of the trilogy contains the presentation and evaluation of the data about the methods in obstetric anaesthesia. In 2002 questionnaires were mailed to 750 randomly selected departments of anaesthesia, 384 hospitals (51.2%) responded of which 278 had an obstetric unit. Caesarean section rate was 22.5+/-8.2% and for elective caesarean section spinal anaesthesia was mostly used. General anaesthesia was never used in 58.3% of Swiss, 10.2% of German, and 21.1% of Austrian hospitals. For non-elective caesarean section 42.1% of the hospitals often used a spinal anaesthesia, and 44.8% sometimes, in Switzerland these were 92.9% and 7.1%, respectively. Pain relief for labour was usually achieved with epidural anaesthesia or drugs. The trend from general to regional anaesthesia for caesarean section is continued, as is the trend from local infiltrative techniques to epidural anaesthesia for vaginal delivery. Switzerland was in the forefront for these developments.     

Comparison of predicted and perceived pain from epidural and spinal puncture in patients undergoing elective caesarean section

The intensity of pain expected by patients before an epidural and/or a spinal puncture is uncertain. The main purpose of this study was to identify and compare the intensity of pain predicted and perceived by patients having an epidural and a spinal procedure. After screening for relevant exclusion criteria, 50 women who were undergoing elective caesarean section under combined spinal-epidural anaesthesia (double-segment technique) were enrolled in the study. Infiltration anaesthesia prior to needle insertion was performed for the epidural but not the spinal puncture. Pain assessments, using a 100 mm visual analogue pain scale, were made before (predicted pain) and after (perceived pain) the epidural and the spinal puncture. Predicted pain for epidural and spinal insertion (epidural 60.6 +/- 20.5 mm, spinal: 55.1 +/- 24 mm) was significantly higher than the pain perceived (epidural 36.3 +/- 20 mm, spinal 46.1 +/- 23.2 mm) (epidural P < 0.001, spinal P = 0.031). Patients who were scheduled for an elective caesarean section under combined spinal-epidural anaesthesia predicted 1.2- to 1.7-fold stronger pain intensity than they perceived during the procedure. Patients should be informed that a regional anaesthetic, especially epidural, procedure is often less painful than the patient's expectation.     

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

The conversion of epidural analgesia during labour to surgical anaesthesia for Caesarean section can have important medical and medicolegal implications. This survey sought to establish the current management for extending epidural blockade for emergency Caesarean section. A postal questionnaire was sent to the lead obstetric anaesthetist in all maternity units in the UK (n = 254). The response rate was 82% (n = 209). Of those surveyed, 68% (136) give the full dose of the local anaesthetic mixture in the delivery room, whilst 12.5% (25) initiate the top-up in the delivery room and give the remainder of the dose in theatre. Fifteen per cent (30) transfer the woman to theatre before commencing anaesthesia and 34% (68) give a test dose before the full anaesthetic dose. Guidelines for converting labour analgesia to anaesthesia for emergency Caesarean section were available in 64% (128) units. Bupivacaine 0.5% was the most commonly used agent, being used as the sole agent by 41.5% (81) units and in combination by a further 18% (36). Adrenaline was added to the chosen local anaesthetic by 30% (60) whilst 12% (24) added bicarbonate. In all, 13 combinations of local anaesthetics and adjuncts were used. The mode time to transfer the patient to theatre was 1 min. Of the 161 respondents who commenced anaesthesia in the delivery room, 71% (114) did not monitor the patient during transfer, whilst 87% (140) had ephedrine immediately available. Thirty-three respondents reported a total of 43 adverse incidents associated with the extension of epidural blockade. These included high blocks, inadequate blocks and possible intravascular injections, the latter resulting in two seizures and one cardiac arrest.     

Incidence and characteristics of failures in obstetric neuraxial analgesia and anesthesia: a retrospective analysis of 19,259 deliveries

A retrospective analysis was performed on 19,259 deliveries that occurred in our institution from January 2000 to December 2002. Anesthesia records and quality assurance data sheets were reviewed for the characteristics and failure rates of neuraxial blocks performed for labor analgesia and anesthesia. The neuraxial labor analgesia rate was 75% and the overall failure rate was 12%. After adequate analgesia from initial placement, 6.8% of patients had subsequent inadequate analgesia during labor that required epidural catheter replacement. Ultimately 98.8% of all patients received adequate analgesia even though 1.5% of patients had multiple replacements. Six percent of epidural catheters had initial intravenous placement but 46% were made functional by simple manipulations without higher subsequent failure. Unintended dural puncture occurred in 1.2% of labor neuraxial analgesia. The incidences of overall failure, intravenous epidural catheter, wet tap, inadequate epidural analgesia and catheter replacement were lower in patients receiving combined spinal-epidural versus epidural analgesia. For cesarean section, 7.1% of pre-existing labor epidural catheters failed and 4.3% of patients required conversion to general anesthesia. Spinal anesthesia for cesarean section had a lower failure rate of 2.7%, with 1.2% of the patients requiring general anesthesia. The overall use of general anesthesia decreased from 8% to 4.3% over the three-year period. Furthermore, regional anesthesia was used in 93.5% of cesarean deliveries with no anesthetic-related mortalities. Future investigations should identify acceptable international standards, risk factors associated with failure and methods to reduce failure before cesarean section.     

Spinal myoclonus following combined spinal-epidural anaesthesia for Caesarean section

A nulliparous woman presented with pre-eclampsia at 39 weeks' gestation. A combined spinal-epidural anaesthesia was employed for Caesarean section but the spinal component produced no discernible block, so the epidural was topped up with 20 ml ropivacaine 0.75% without problem and surgery was uneventful. A week after delivery she developed twitching of her legs and opisthotonus, that was initially thought to be eclampsia but was subsequently diagnosed as spinal myoclonus. She was treated with oral carbamazepine and diazepam, with improvement over the next 4 days, and discharged home a week later taking oral carbidopa and levodopa. Her symptoms resolved completely 6 months after the initial event.     

Failed spinal analgesia after a combined spinal epidural anaesthesia for Caesarean section

A case of failed spinal analgesia with a combined spinal epidural anaesthesia (CSE) for Caesarean section is described. The lack of desired effect following an inconspicuous spinal, epidural or combined regional anaesthesia by an experienced anaesthetist is a rare and unexpected event. Especially when repeatedly observed in one patient,one should consider modified anatomical conditions of the affected spinal regions. We discuss the differential diagnosis which consists of inherent and acquired modification of tissue, neoplasia and vascular or infectious diseases. This case also confirms that not every adverse event after spinal or extradural anaesthesia is necessarily caused by the puncture.     

Real-time ultrasonic observation of combined spinal-epidural anaesthesia

BACKGROUND AND OBJECTIVE: The quality of combined spinal-epidural anaesthesia mainly depends on accurate identification of the epidural space. The real-time ultrasound control of the procedure for puncture was therefore evaluated. METHODS: Thirty parturients scheduled for Caesarean section were randomized to three equal groups. Ten control patients received conventional combined spinal-epidural anaesthesia. Ten of the remaining patients received ultrasonic scans by an offline scan technique, and 10 received online imaging of the lumbar region during epidural puncture. The epidural space was identified and needle advancement was surveyed through the interspinal and flaval ligaments. The number of attempts to advance the needle to achieve a successful puncture was measured and compared, as well as the number of vertebral interspaces punctured before successful entry into the epidural space. RESULTS: There was no difference between patient characteristics in the three groups. The visualization of the epidural structures and of the needle manipulations was very effective. In the ultrasound group, the reduction in the number of attempts at puncture was significant (P < 0.036). The number of interspaces necessary for puncture was reduced (P < 0.036) in the ultrasound online group compared with controls. The number of spinal needle manipulations was significantly reduced (P < 0.036). CONCLUSIONS: Real-time ultrasonic scanning of the lumbar spine is an easy procedure. It provides an accurate reading of the location of the needle tip and facilitates the performance of combined spinal-epidural anaesthesia.     

Combined spinal epidural anaesthesia in a primigravida with valvular heart disease

Purpose

This is the first report describing combined spinal epidural anaesthesia for labour and unexpected Caesarean section in a patient with mitral and aortic stenosis and insufficiency.

Clinical features

The patient was a 30-yr-old GIPO with a history of rheumatic fever. She had moderate stenosis and insufficiency of the mitral and aortic valves. Combined spinal and epidural anaesthesia was used throughout labour and subsequent Caesarean section. The patient remained haemodynamically stable throughout the procedure.

Conclusion

Carefully planned regional anaesthesia was safely used for labour and operative delivery in this parturient with mitral and aortic valvular disease.     

Paraesthesia during the needle-through-needle and the double segment technique for combined spinal epidural anaesthesia

Paraesthesia during regional anaesthesia is an unpleasant sensation for patients and, more importantly, in some cases it is related to neurological injury. Relatively few studies have been conducted on the frequency of paraesthesia during combined spinal epidural anaesthesia. We compared two combined spinal epidural anaesthesia techniques: the needle-through-needle technique and the double segment technique in this respect. We randomly allocated 116 parturients undergoing elective Caesarean section to receive anaesthesia using one of these techniques. Both techniques were performed using a 27G pencil point needle, an 18G Tuohy needle, and a 20G multiport epidural catheter from the same manufacturer. The overall frequency of paraesthesia was higher in the needle-through-needle technique group (56.9% vs. 31.6%, p = 0.011). The frequency of paraesthesia at spinal needle insertion was 20.7% in the needle-through-needle technique group and 8.8% in the double segment technique group; whereas the frequency of paraesthesia at epidural catheter insertion was 46.6% in the needle-through-needle technique group and 24.6% in the double segment technique group.     

Epidural versus general anaesthesia for elective Caesarean section Effect on Apgar score and acid-base status of the newborn

Elective Caesarean section deliveries over a 5-year period were studied to compare the effect of epidural block with general anaesthesia on the condition of the infant at birth. The Apgar score and umbilical arterial acid-base status were used as determinants of the latter. Epidural block was used in 139 (22.8%) mothers while 471 (77.2%) were performed under general anaesthesia. No babies in the epidural group were severely depressed (Apgar less than 4), compared with 6.2% in the general anaesthesia group. Only 4.3% of the epidural sections were moderately depressed (Apgar 4-6), compared with 15.4% of the others. These differences remained highly significant when infants of less than 2500 g were excluded, and when matched groups were compared. Mean umbilical arterial pH was similar within the two groups (pH 7.28), and was not consistent with asphyxia in almost 90% of the depressed infants. The findings suggest that general anaesthesia, rather than asphyxia or aortocaval compression, is responsible for most of the depressed infants born by elective Caesarean section. This may involve over 20% of babies delivered in this manner, so greater use of epidural block for elective Caesarean section is recommended. Further investigations are required to improve results with general anaesthesia.