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There are multiple methods of assessing the height of block before caesarean section under regional anaesthesia, and surveys of practice suggest considerable variation in practice. So far, little emphasis has been placed on the guidance to be gained from published research literature or textbooks. We therefore set out to investigate the methods of block assessment documented in published articles and textbooks over the past 30 years. We performed two searches of PubMed for randomised clinical trials with caesarean section and either spinal anaesthesia or epidural anaesthesia as major Medical Subject Headings. A total of 284 papers, from 1984 to 2013, were analysed for methods of assessment of sensory and motor block, and the height of block deemed adequate for surgery. We also examined 45 editions of seven anaesthetic textbooks spanning 1950-2014 for recommended methods of assessment and height of block required for caesarean section. Analysis of published papers demonstrated a wide variation in techniques, though there has been a trend towards the increased use of touch, and an increased use of a block height of T5 over the study period. Only 115/284 (40.5%) papers described the method of assessing motor block, with most of those that did (102/115; 88.7%) describing it as the 'Bromage scale', although only five of these (4.9%) matched the original description by Bromage. The required height of block recommended by textbooks has risen over the last 30 years to T4, although only four textbooks made any recommendation about the preferred sensory modality. The variation in methods suggested by surveys of practice is reflected in variation in published trials, and there is little consensus or guidance in anaesthetic textbooks., (© 2014 The Association of Anaesthetists of Great Britain and Ireland.)

Background: The Obstetric Anaesthetists' Association (OAA) has facilitated national surveys in obstetric anaesthesia since 1998. We wanted to examine trends in OAA-approved surveys since this time., Methods: OAA-approved surveys performed between January 1998 and December 2012 were examined for the year they were carried out, the format (postal or electronic), the target group and the response rate. We determined whether each survey was presented or published. For each survey published as a substantive paper, we identified the number of times the publication had been cited. We also surveyed lead obstetric anaesthetists and expert witnesses practising in obstetric anaesthesia on the perceived usefulness of OAA-approved surveys., Results: One hundred and thirty-five surveys approved by the OAA were carried out between 1998 and 2012. Response rates have fallen over the years, reaching a current plateau of 65%. Response rates varied with the target group. Seventy-eight percent of surveys were presented and 83% were published in some form. For surveys published as substantive papers (n=34, 25%), the median [IQR (range)] number of citations was 6 [3-11 (0-36)] per publication. Our survey of lead obstetric anaesthetists had a response rate of 62%. Those who replied rated OAA surveys a median [IQR (range)] of 6 [5-7 (1-9)] on a 0-10 scale of usefulness to their clinical practice., Conclusions: Response rates to OAA-approved surveys have declined but remain acceptable despite an increase in the number of surveys performed. Most surveys were presented or published in some form., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

There has been little published work defining 'normal' thromboelastography (TEG(®) ) values in healthy parturients, and few large studies defining reference ranges for traditional coagulation tests in this patient group. Our aim was to establish peri-operative reference ranges for TEG and for standard laboratory coagulation tests in our pregnant population. Fifty healthy term parturients presenting for elective caesarean section under spinal anaesthesia had blood samples taken pre-operatively, on arrival in the recovery room and, in a subset of 33 women, 4 h after routine thromboprophylaxis with enoxaparin 40 mg. All three samples had TEG analysis, the first and second having standard laboratory coagulation tests in addition. Reference ranges for our pregnant population were established, demonstrating a hypercoagulable state in term parturients and a significant effect of enoxaparin. The standard coagulation reference ranges were within 98% of the local non-pregnant ranges. These reference ranges provide a useful comparator for peri-operative TEG and routine coagulation analysis in term parturients., (Anaesthesia © 2012 The Association of Anaesthetists of Great Britain and Ireland.)

We assessed the ability of palpating the radial arterial pulse and observing the oximeter trace to estimate the automated non-invasive systolic pressure reading in 20 healthy female volunteers and 20 parturients undergoing spinal anaesthesia for elective caesarean section. Using real-time values of cuff pressure during inflation/deflation, the pressure was recorded when the manually palpated radial arterial pulse or pulse oximeter waveform disappeared and reappeared. The actual measured systolic pressure was noted and the results compared using Bland-Altman analysis. In the volunteers, the bias/precision for radial arterial palpation was -12.9/22.1 mmHg (inflation) and -9.7/16.7 mmHg (deflation), and for oximetry 29.5/18.8 mmHg (inflation) and -20.7/21.7 mmHg (deflation). In the parturients, the bias/precision was -19.0/47.6 mmHg (inflation) and -15.5/51.0 mmHg (deflation) for arterial palpation, and 22.6/16.1 mmHg (inflation) and -14.2/19.9 mmHg (deflation) for oximetry. Our results suggest that neither method is accurate at estimating the non-invasive systolic pressure, with all except oximetry (inflation) underestimating it by approximately 10-20 mmHg and with poor precision., (© 2010 The Authors. Anaesthesia © 2010 The Association of Anaesthetists of Great Britain and Ireland.)

Background: When monitoring postoperative urine output there is no guidance specific to obstetrics. Factors such as peri-operative oxytocin infusions add further complexity. Our aim was to determine a normal range for urine output after elective caesarean section under neuraxial anaesthesia., Methods: Sixty women were recruited and for 24h from the time of urethral catheterisation, we recorded urine output and fluid input. We also measured intra-operative blood loss, use of prophylactic oxytocin infusion and markers of renal function. Data were compared with Mann-Whitney U-tests or paired t tests., Results: Oxytocin infusions were used in 45 women (75%). Median (95% CI) urine output in the first 6h was 0.8 (0.4-1.9) mL kg(-1)h(-1) in women receiving oxytocin compared to 1.4 (0.7-2.2)mL kg(-1)h(-1) in those who did not (P=0.02). Urine output for all women at 12 and 18 h was 2.0 (0.7-5.7) and 1.9 (0.5-4.5)mL kg(-1)h(-1). Blood loss was 0.4 (0.2-0.8)L in women with oxytocin infusions and 0.3 (0.1-0.4)L in those without (P=0.003). Mean (SD) pre- and postoperative urine osmolality was 622.5 (185.7) and 293.0 (135.1) mosm/kg, respectively (P<0.0001)., Conclusions: Urine output varied widely between subjects, especially after the first 6h and was further reduced by the use of oxytocin infusion. This may have been a direct effect or related to increased blood loss in this group. Oxytocin use should be accounted for when setting a minimum postoperative urine output. We also found high pre-operative urine osmolalities suggesting significant dehydration., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Background: Haemoglobin concentration measured using the HemoCue is accurate for capillary and venous/arterial blood, provided the recommended sampling method is strictly observed. Analysis of blood, particularly of capillary samples, using the HemoCue is useful during caesarean section. The toe might be preferred to the thumb since it is numb during neuraxial anaesthesia, but whether sampling at either site is accurate in this situation, given the cardiovascular effects of anaesthesia and pregnancy, is not known. We aimed to compare haemoglobin values measured in venous and capillary samples (toe and thumb) during caesarean section under neuraxial anaesthesia., Method: Fifty healthy women having caesarean section under spinal or combined spinal-epidural anaesthesia were included. At the end of surgery, the great toe and thumb (non-i.v. fluid side) were lanced as recommended for a HemoCue reading. A venous blood sample (non-i.v. fluid side) was also taken and sent for formal laboratory measurement and tested with the HemoCue. Bland-Altman analysis was applied to the haemoglobin values., Results: Bias (mean difference) and precision +/- 2 SD were respectively 0.2 +/-1.6 for laboratory vs. toe, 0.1 +/-1.8 for laboratory vs. thumb, and 0.2 +/-1.6 laboratory vs. venous., Conclusion: Our results suggest that in terms of accuracy, the two sites are equally suitable for use during caesarean section under neuraxial anaesthesia., (Copyright 2009 Elsevier Ltd. All rights reserved.)

Background: We assessed the effect of warming intravenous fluids during elective caesarean section under combined spinal-epidural anaesthesia in a blinded, randomised controlled trial., Method: Seventy-five women having elective caesarean section were randomly assigned to receive all intravenous fluids at room temperature, or heated in a cabinet set at 45 degrees C or via a Hotline fluid warmer (Smiths Medical International Ltd, Watford, Herts, UK). After 10 mL/kg crystalloid preload, combined spinal-epidural anaesthesia was performed. Core and ambient temperatures, thermal comfort and shivering were measured every 15 min thereafter. The primary outcome was the temperature at 60 min., Results: Temperature decreased in all groups. Although the temperature decrease at 60 min was similar in the heated cabinet and Hotline groups, the room temperature group exhibited a greater decrease [difference 0.4 degrees C (95% CI 0.2-0.6 degrees C); P=0.015]. More women felt cold in the room temperature group (8: 32%) than in the heated cabinet set (3: 12%) and Hotline (1: 4%) groups (P=0.02), but the incidence of shivering was similar: 11 (44%), 9 (36%) and 7 (28%) respectively. Apgar scores and neonatal cord gases were similar., Conclusion: Warming intravenous fluids mitigates the decrease in maternal temperature during elective caesarean section under combined spinal-epidural anaesthesia and improves thermal comfort, but does not affect shivering. Intravenous fluids should be warmed routinely in elective caesarean section, especially for cases of expected long duration, but the use of pre-warmed fluids is as efficient and cheaper than using a Hotline fluid warmer.

We contacted the duty obstetric anaesthetist in 219 of the 220 consultant-led maternity units in the UK (99.5%) and asked about departmental and individual practice regarding temperature management during Caesarean section. Warming during elective Caesarean section was routine in 35 units (16%). Intravenous fluid warmers were available in 213 units (97%), forced air warmers were available in 211 (96%) and warming mattresses were available in 42 (19%). Only 18 (8%) departments had specific guidelines for temperature management during Caesarean section. Personal intra-operative practice was variable, although all of those contacted would initiate some form of active temperature management after a mean (SD) volume of blood loss of 1282 (404) ml, length of surgery of 78 (24) min, or core body temperature (if measured) of median (IQR [range]), 36 (35.5-36 [34-37.2]) degrees C.

Background: Lidocaine-bicarbonate-adrenaline mixtures are commonly used for epidural bolus doses for emergency caesarean section. Previous research has shown that adrenaline degrades completely 24 h after mixing. Anecdotal enquiries suggest that anaesthetists who use such mixtures commonly prepare the solution ahead of use, despite a lack of data about its stability between 0 and 24 h. The aim of this study was to monitor the degradation of adrenaline in the above mixture over 20 h., Methods: 2 mL of sodium bicarbonate 8.4% was added to 20 mL of 2% lidocaine; 2 mL of this mixture was discarded and 0.1 mL of adrenaline 1:1000 added. The mixtures were stored in plastic syringes at 24 degrees C unprotected from light (n=3) or in the dark (n=3). Non-alkalinised controls were also prepared. Adrenaline and lidocaine were assayed by high performance liquid chromatography at 0, 2, 4, 6 and 20 h., Results: In the bicarbonated mixture exposed to light, chemical degradation of adrenaline was fast at room temperature, only 73.0+/-3.6% of adrenaline remaining after 6h. In the dark, the stability of adrenaline improved and 95.8+/-3.6% remained after 6h. Negligible degradation occurred in the absence of bicarbonate in either condition. Lidocaine concentrations remained unchanged regardless of the storage conditions., Conclusions: This study suggests that preparation of pH-adjusted lidocaine-adrenaline mixtures in advance and prolonged storage in the light is inadvisable.

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.

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.

We describe a parturient with hyperkalaemic periodic paralysis who presented for induction of labour and subsequently, caesarean section. Epidural analgesia and anaesthesia were used successfully in a multidisciplinary plan aimed at avoiding a peripartum attack and providing safe delivery. Management of this rare condition is discussed along with a review of the available literature.

One hundred women were randomly allocated to the left lateral, Oxford or sitting position for induction of combined spinal-epidural anaesthesia for Caesarean section using 2.5 ml hyperbaric bupivacaine 0.5% and 10 mug fentanyl. Women in the left lateral were then turned to the right lateral position; women in the Oxford position were turned to the same position on their opposite side; and women in the sitting group were turned to the supine left tilt position. Women remained in these positions until ready for surgery, which was conducted in the supine position with a wedge placed under the right hip. Ephedrine requirements before re-positioning for surgery were less in the sitting position than in the other two positions: median (IQR [range]) doses for the lateral, Oxford and sitting groups were 21 (12-30 [6-48]), 18 (7.5-24 [6-48]) and 12 (6-21 [6-42]) mg, respectively; p = 0.04. Sensory block to touch sensation at the T5 dermatomal level was most quickly achieved in the lateral position with median (IQR [range]) block onset times for the lateral, Oxford and sitting groups of 9 (6-13 [4-30]), 15.5 (9-22 [4-34]) and 14 (9-18[6-36]) min, respectively; p = 0.004. In the Oxford position, more epidural catheters required dosing to achieve a sensory block of T5 before surgery: the number of patients (proportion) bolused in the lateral, Oxford and sitting groups was 1 (3%), 7 (22%) and 1 (3%), respectively; p = 0.01. We did not demonstrate any advantage in using the Oxford position for combined spinal-epidural anaesthesia for elective Caesarean section.

We compared ropivacaine 0.75% and bupivacaine 0.5% for extending low-dose epidural analgesia for emergency Caesarean section, using a prospective double-blind randomised controlled trial design. The trial was halted after 45 patients were studied (23 ropivacaine; 22 bupivacaine) because bupivacaine was replaced by levobupivacaine in our unit. Time to reach T4 for loss of cold sensation was similar in both groups, although analgesic supplementation was required less often in the ropivacaine group than in the bupivacaine group (2/23 vs. 9/21; p = 0.01).

The recommended dose of Syntocinon used for uterine contraction at Caesarean section is5 units intravenously, given slowly. We conducted a survey of the use of Syntocinon at Caesarean section among 240 lead obstetric anaesthetists in the UK in 2001 and found that 155 (87%) of the 179 (75%) respondents gave 10 units, 77 of them (50%) by rapid bolus. The risks of Syntocinon, especially given by rapid injection, were highlighted in the report of the Confidential Enquiries into Maternal Deaths in the UK (1997-99), which was published at the end of 2001, and so the survey was repeated in 2002. Of the 256 forms sent, 198 completed replies were returned (77%); these indicated a dramatic change of practice: only 30 (15%) now gave 10 units and only 7 of these (23%) by a rapid injection. One hundred and sixty-seven respondents to the second survey (84%) stated they had changed their practice and 159 of these (95%) gave the Confidential Enquiries report as the main reason for change. These results highlight the importance of the Confidential Enquiries as a means of improving practice.

The ability of glycopyrronium to reduce the severity of hypotension following subarachnoid block in parturients with a relative bradycardia was evaluated in a double-blind randomised controlled study. Women with a resting heart rate of < or = 80 beat x min(-1) presenting for elective Caesarean section were randomly allocated to receive either glycopyrronium 2 microg x kg(-1) or normal saline intravenously once positioned for combined spinal-epidural anaesthesia. Following spinal injection of 2.6 ml hyperbaric bupivacaine 0.5% and fentanyl 15 microg, women randomly allocated to the saline group were given 6 mg ephedrine so that all parturients received some prophylaxis against hypotension other than the fluid preload. Further ephedrine and fluid boluses were administered if mean arterial pressure fell 20% or more from resting values. Using a sequential analysis technique, analysis after the first 20 subjects indicated the study should be stopped, with no difference in ephedrine requirements or hypotension between the groups. We conclude that pretreatment with glycopyrronium 2 microg x kg(-1) is no more effective than 6 mg ephedrine in preventing hypotension following subarachnoid block in parturients with relatively low resting heart rates.

Unfractionated heparin is widely used for prophylaxis against venous thromboembolism after Caesarean section. We performed a survey of thromboprophylactic methods after elective Caesarean section in 50 maternity units in the United Kingdom. We found that a variety of regimens were used. Thirteen (26%) used subcutaneous unfractionated heparin at standard (non-pregnant) doses. We then studied anti-Xa activity in women following elective Caesarean section under regional anaesthesia. Initially, eight women were given 5000 U unfractionated heparin subcutaneously after surgery and anti-Xa activity was measured 1, 2, 3, 4, 5, 6, 8 and 10 h after administration. There was no detectable anti-Xa activity in any of the samples so the dose was increased to 7500 U in a further five women and a single anti-Xa assay performed at 3 h when peak activity should occur. Again, no activity was detected so the dose was increased to 10 000 U heparin in a final group of 10 women and anti-Xa activity measured at 0.5, 1, 1.5, 2, 3, 4, 5 and 6 h. Although there was some activity after 10 000 U heparin, the level was below that accepted for prophylaxis. If anti-Xa activity is an appropriate monitor of prophylactic unfractionated heparin, doses up to 10 000 U are inadequate. Since there is evidence that enoxaparin is effective at producing adequate prophylactic anti-Xa activity following Caesarean section, we suggest abandoning the use of unfractionated heparin in favour of enoxaparin for this purpose.

A new classification for caesarean section was developed in a two-part study conducted at six hospitals. Initially, 90 anaesthetists and obstetricians graded ten clinical scenarios according to five different classification methods--visual analogue scale; suitable anaesthetic technique; maximum time to delivery; clinical definitions; and a 1-5 rating scale. Clinical definitions was the most consistent and useful, and this method was then applied prospectively to 407 caesarean sections at the same six hospitals. There was close agreement (86%) between anaesthetists and obstetricians for the five-point scale (weighted kappa 0.89), increasing to 90% if two categories were combined (weighted kappa 0.91). We suggest that the resultant four-grade classification system--(i) immediate threat to life of woman or fetus; (ii) maternal or fetal compromise which is not immediately life-threatening; (iii) needing early delivery but no maternal or fetal compromise; (iv) at a time to suit the patient and maternity team--should be adopted by multidisciplinary groups with an interest in maternity data collection.

We compared the preparation times of three solutions commonly used for epidural top-up for emergency Caesarean section. Twenty-two anaesthetists were asked to prepare fresh solutions in random order as quickly as possible: 0.5% bupivacaine 20 ml (B); 2% lidocaine 20 ml with 1:200,000 epinephrine (LE); and 0.5% bupivacaine 10 ml and 2% lidocaine 10 ml with 1:200,000 epinephrine and 8.4% sodium bicarbonate 2 ml (BLEB). Preparation times for B were approximately half of those for LE, which in turn were approximately half of those for BLEB (P = 0.0001). If local anaesthetic solutions with additives such as epinephrine or bicarbonate are prepared just before emergency Caesarean section, any possible reduction in onset time that they might afford may be offset by the additional preparation time required.

We conducted a prospective double-blind randomised trial to compare bupivacaine 0.5%; a 50 : 50 mixture of bupivacaine 0.5%/lignocaine 2% with 1 : 200 000 adrenaline (final concentration); and lignocaine 2% with 1 : 200 000 adrenaline for converting a low-dose labour epidural into a block adequate for emergency Caesarean section. Ninety patients were studied, 30 in each group. There was no difference between the groups in the time taken for bilateral loss of cold sensation to reach T4. Onset time was unaffected by the existing sensory level pre-Caesarean section top-up; the number of low-dose top-ups in labour; the total dose of bupivacaine in labour; or maternal weight or height. Three patients in the lignocaine with adrenaline group had blocks that reached the cervical dermatomes and three in the same group required general anaesthesia for inadequate anaesthesia, compared with none in the other groups (both p = 0.04).

We describe a 27-year-old primigravida suffering from cystic fibrosis. Her chest was colonised with Burkholderia cepacia and she was in respiratory failure for which she required constant nasal intermittent positive pressure ventilation. In view of her rapid deterioration, Caesarean section was performed under epidural anaesthesia at 25 weeks gestation. A live 790-g boy was delivered. Post-operatively she made steady progress for 5 days although still requiring nasal ventilatory support. Thereafter she developed pneumonia and required tracheal intubation and ventilation on the eighth day. Her increasing hypoxaemia and pulmonary hypertension failed to respond to any therapy including inhaled nitric oxide and she died on the tenth postoperative day.

We describe the anaesthetic management of a parturient with Noonan's syndrome. Her problems included severe cardiac disease, facial abnormalities and extreme phobia to needles. After intrauterine death at 30 weeks gestation, induction of labour was attempted and extradural analgesia initiated using low-dose bupivacaine. She failed to progress and underwent Caesarean section under general anaesthesia using awake oral fibreoptic intubation.

There has been little published work defining 'normal' thromboelastography (TEG®) values in healthy parturients, and few large studies defining reference ranges for traditional coagulation tests in this patient group. Our aim was to establish peri-operative reference ranges for TEG and for standard laboratory coagulation tests in our pregnant population. Fifty healthy term parturients presenting for elective caesarean section under spinal anaesthesia had blood samples taken pre-operatively, on arrival in the recovery room and, in a subset of 33 women, 4 h after routine thromboprophylaxis with enoxaparin 40 mg. All three samples had TEG analysis, the first and second having standard laboratory coagulation tests in addition. Reference ranges for our pregnant population were established, demonstrating a hypercoagulable state in term parturients and a significant effect of enoxaparin. The standard coagulation reference ranges were within 98% of the local non-pregnant ranges. These reference ranges provide a useful comparator for peri-operative TEG and routine coagulation analysis in term parturients. [ABSTRACT FROM AUTHOR]

Responds to S.K. Pattnaik and R. Bodra's article published in a 1999 issue of the periodical 'Anaesthesia,' on similarities between the institution of epidural blockade for elective and emergency cesarean sections. Preparation of lidocaine and epinephrine solution; Types of central nervous system toxicity.

The article presents a reply to Dr. D. M. Levy and his interest in the author's editorial which points out that Hamer Hodges's paper was regarded as the first detailed analysis of the use of thiopental plus suxamethonium for caesarean section.