Computerized axial tomo-epidurographic and radiographic documentation of unilateral epidural analgesia

A 23-year-old primigravid patient who received epidural analgesia for pain of labour presented with persistent, apparently irremediable, unilateral analgesia. Computerized axial tomo-epidurography demonstrated absence of circumferential spread due to lateral placement of the catheter. Transforaminal escape of contrast medium into the paravertebral area had occurred and anterior and posterior midline partitioning of the epidural space was obvious. All the usual measures to promote contralateral analgesia, except re-insertion of the catheter, had been tried without success.     

A comparative study of patient-controlled epidural fentanyl and single dose epidural morphine for post-caesarean analgesia

In a prospective, randomized, double-blinded study, 23 patients who had undergone Caesarean delivery under epidural anaesthesia were assessed to evaluate the effectiveness of patientcontrolled epidural analgesia (PCEA) with fentanyl compared with a single dose of epidural morphine for postoperative analgesia. Group A (n = 11) received epidural fentanyl 100 μg intraoperatively, then self-administered a maximum of two epidural fentanyl boluses 50 μg (10 μg · ml^?1) with a lockout period of five minutes for a maximum of two doses per hour. Group B (n = 11) received a single bolus of epidural morphine 3 mg (0.5 mg · ml^?1) intraoperatively and received the same instructions as Group A but had their PCA devices filled with 0.9% NaCl. Patients were assessed up to 24 hr for pain, satisfaction with pain relief, nausea and pruritus using visual analogue scales (VAS). The treatments for inadequate analgesia, nausea and pruritus as well as time to first independent ambulation were recorded. The ventilatory response to carbon dioxide challenge was measured at four and eight hours. Pain relief, satisfaction with pain relief, and the use of supplemental analgesics were similar in both groups. The mean 24 hr dose of epidural fentanyl used by group A patients was 680 μg. Pruritus was less common in Group A patients at the 8 and 24 hr observation periods (P < 0.0125). Both groups experienced the same degree of nausea and clinically unimportant respiratory depression. We conclude that PCEA with fentanyl provides analgesia equal to a single dose of epidural morphine and may be suitable for patients who have experienced considerable pruritus after epidural morphine adminstration.     

Combined spinal epidural block versus spinal and epidural block for orthopaedic surgery

In a controlled study a single segment combined spinal epidural (CSE) block was compared with spinal or epidural block for major orthopaedic surgery. Seventy-five patients, age 52–86 yr, were randomly assigned to receive one of the three blocks. Bupivacaine 0.5% was used for surgical analgesia. The postoperative pain relief after 4.0 mg epidural morphine was compared with the analgesic effect of 0.2 or 0.4 mg morphine administered intrathecally. With the spinal technique good or excellent surgical analgesia and muscle relaxation were achieved rapidly (11.8 ± 1.1 min). The time taken to provide an equally effective and reliable block with the CSE technique was no longer (14.9 ± 2.2 min). For epidural block with the catheter technique more time was required (35.9 ± 3.9 min) to provide acceptable surgical conditions (P < 0.05). Perioperative sedatives and concomitant analgesics were required more frequently and in larger doses by the patients undergoing surgery with epidural block (P < 0.05) than with CSE or spinal block. Our study demonstrated that the analgesia after surgery provided by 0.2 and 0.4 mg morphine administered intrathecally was comparable to that provided by 4.0 mg of epidural morphine. It is concluded that the analgesia and surgical conditions provided by the spinal and CSE blocks were similar and were superior to those provided by an epidural block.     

Lumbar and thoracic epidural analgesia via the caudal approach for postoperative pain relief in infants and children

Thirty infants scheduled for a variety of gastrointestinal, genitourinary and thoracic surgical procedures were selected for insertion of lumbar or thoracic epidural catheters via the caudal approach using either an Intracath or a Burron continuous brachial plexus kit. The catheters were inserted with ease by residents in training and no catheter-related complications were encountered. Lidocaine 0.5 per cent with 1:200,000 epinephrine was then injected to assure proper placement of the catheter before narcotics were administered. Postoperative analgesia was adequate in all patients using preservative-free morphine 0.05 mg.kg-1. The mean dosing interval was 15 hr and no episodes of nausea, vomiting, hypotension or histamine release were noted. Urinary retention occurred in two infants and one infant became apnoeic three hours after epidural morphine administration but responded to naloxone and pulmonary ventilation with bag and mask. In conclusion, epidural catheters placed via the caudal approach are a safe and effective means of providing postoperative pain control in infants using preservative-free morphine. However, the use of epidural narcotics in infants less than two years of age is restricted to those who will receive intensive care unit monitoring postoperatively so that if apnoea occurs, rapid intervention can be taken by skilled nursing personnel.     

Piriformis pyomyositis mimicking epidural abscess in a parturient

A case is presented of a patient who developed fever, leukocytosis, severe back pain, local overlying spinal tenderness, and left leg weakness on the fifth day postpartum. The patient had epidural anaesthesia for ten hours duration, before and during a forceps delivery. Computerized axial tomography (CT) and magnetic resonance imaging (MRI) of the pelvis and lumbar spine revealed swelling of the left iliacus and piriformis muscles, but no epidural abscess. A diagnosis of isolated piriformis pyomyositis with secondary sciatic nerve irritation was made, and the patient was treated with intravenous antibiotics, non-steroidal anti-inflammatory agents, and morphine analgesia. She made a full, uneventful recovery within 50 days, and was discharged requiring no medications.     

Transforaminal escape of a lumbar epidural catheter

A patient is presented whose lumbar epidural catheter was found to lie in the paravertebral tissues during a right radical nephrectomy. The catheter had been placed with the patient awake and the procedure performed in a routine fashion without difficulty or indication of catheter malposition. Four ml of 2% CO2 lidocaine were initially injected as a test dose without any demonstrable effect. After the induction of general anaesthesia, fentanyl 100 mu and 0.25% bupivacaine 10 ml were injected slowly into the catheter. Previous studies suggest that transforaminal escape of an epidural catheter occurs after 1-6% of insertions. It may occur without nerve root symptoms during catheter placement. The authors recommend that epidural catheters be introduced whilst the patients are awake and an effective block demonstrated before induction of general anaesthesia.     

Continuous suprascapular nerve block for analgesia of scapular fracture

Fracture of the scapular is uncommon but painful. A case is described in which a comminuted scapular fracture was treated with a continuous suprascapular nerve block. With the patient lying supine an epidural needle was directed towards the scapular notch via a superior approach and an epidural catheter was placed when the notch was believed to have been identified. Repeat injections of 10 ml bupivacaine 0.25 per cent with 1/200,000 epinephrine provided analgesia within minutes and a duration of 8-10 hr. Injection of 10 ml radio-opaque dye demonstrated the catheter to be lateral to the scapular notch. However, dye dispersed throughout the supraspinous fossa including the scapular notch thus blocking the suprascapular nerve. This case demonstrates that continuous suprascapular nerve block can be performed for five days and that location of the scapular notch is less important than previously thought.     

Obstetrical epidural anaesthesia in a rural Canadian hospital

Few rural hospitals offer obstetric epidural analgesia services and of those that do, there is a paucity of information about these anaesthetics. A retrospective review was conducted of all obstetrical epidurals from 1984–1988 in an 85-bed hospital in Saskatchewan to examine the indications, complications, and infant outcomes. During that period there were 1224 deliveries. From a total of 915 vaginal deliveries, 42 (4.6%) received an epidural. Caesarean sections numbered 309:183 (59.3%) were with epidural analgesia of which 69 were urgent and 114 elective. The overall complication rate was 23% with the most important being hypotension (12%), dural punctures (1.8%), in-adequate block requiring an intravenous supplement (4.0%) or a general anaesthetic (3.1%). Infant outcomes were favourable except for two unrelated intra-uterine deaths preceding labour.     

Fluid through the epidural needle does not reduce complications of epidural catheter insertion

Epidural catheter insertion may be associated with blood vessel trauma or nerve root irritation. The purpose of this study was to assess whether the injection of small amounts of fluid through the Tuohy needle prior to catheter insertion reduced the incidence of these and other minor complications. Two hundred patients in labour, requesting epidural analgesia, were randomly assigned to one of three groups: Group I--the catheter was inserted without previous injection of fluid; Group II--3 ml, 1.5 per cent lidocaine hydrochloride was injected through the needle prior to catheter insertion; Group III--3 ml, saline was injected prior to catheter insertion. There were no differences among the groups in the incidence of blood vessel trauma or paraesthesiae. We conclude that there is no advantage in injecting of fluid routinely into the epidural space prior to catheter insertion.     

Post-caesarean section analgesia: a comparison of epidural butorphanol and morphine

Epidural butorphanol 1, 2 and 4 mg were compared with morphine, 5 mg, for postoperative analgesia in 92 consenting, healthy, term parturients who had undergone Caesarean section under epidural lidocaine anaesthesia in a randomized double-blind study. Postoperative pain was assessed using a visual analogue scale and recorded with heart rate, blood pressure and respiratory rate. The demographic characteristics, and the incidences of primary and repeat Caesarean sections, were not different among the four treatment groups. At 15, 30, 45 and 60 min after treatment the median pain scores following butorphanol were similar and lower than those following morphine (P less than 0.05). Calculated median percentage pain relief values for butorphanol were higher than morphine at each of these times (P less than 0.05). At 90 min and 2 hr the pain scores and pain relief values were similar. Beyond 45 min the number of patients requesting supplemental medication and dropping out of the study increased progressively in both the butorphanol and morphine treated patients. The attrition profiles for butorphanol were different from morphine (P less than 0.01). The median time in the study was greater than 24 hr for morphine, and 3, 2.5 and 4 hr for butorphanol, 1, 2 or 4 mg, respectively. No patient developed a clinically important change in heart rate or blood pressure, and none experienced a decrease in respiratory rate below 12 breaths.min-1. One of 69 patients (1.4 per cent) who received butorphanol developed pruritus compared with ten (43 per cent) of 23 patients who received morphine. The global assessments of the adequacy of analgesia were indistinguishable between morphine and butorphanol. Epidural butorphanol provides safe, effective postoperative analgesia, has a prompt onset, and a limited duration.     

Maternal death following epidural anaesthesia for Caesarean section delivery in a patient with unsuspected sepsis

Sepsis in the parturient may be difficult to recognize in light of the physiologial changes associated with pregnancy. The purposes of this report are to highlight the signs and symptoms which indicate an underlying septic process and the management of these patients in the peripartum period. This 32-yr-old GII PI woman with twin gestation presented at 36 wk in labour. Her temperature was 35.3° C, she was normotensive and had a normal white blood cell count. After epidural anaesthesia was administered for Caesarean section, she became apnoeic, pulseless and unresponsive. Despite aggressive cardiopulmonary resuscitation, neither she nor her twin babies survived. Post mortem blood work revealed a considerable left shift of her white blood count (>60% bands) and an onion gap acidosis. Autopsy revealed evidence of widespread Group A beta-haemolytic streptococcal sepsis. Diagnosis of sepsis in the parturient involves assessment of the patient’s temperature, WBC and differential and acid-base status. Evaluation of the intra-vascular volume must precede anaesthetic intervention. Epidural anaesthesia may be considered in the labouring and Caesarean section patient who has been fluid-resuscitated. Emergency operative delivery may result in cardiovascular compromise in the patient with severe sepsis.     

Combined spinal-epidural analgesia in advanced labour

The combined spinal-epidural technique is a modification of epidural analgesia which combines the rapid onset of spinal analgesia with the flexibility of an epidural catheter. We sought to evaluate the effectiveness of an intrathecal opioid — low-dose local anaesthetic combination for parturients in advanced labour, a setting where satisfactory epidural analgesia is often difficult to achieve. The technique was evaluated in an open-label, non-randomized trial using parturients in advanced, active labour for the provision of pain relief during the late first stage and second stage of labour. Thirty-eight term parturients in active, advanced labour received a spinal injection of bu-pivacaine 2.5 mg and sufentanil, 10 μg, via a 25- or 27-gauge Whitacre needle placed into the subarachnoid space through a 17- or 18- gauge Weiss epidural needle which had been placed into the epidural space. This was followed by placement of an epidural catheter for supplemental analgesia if required. Onset of analgesia was noted by asking patients if their contractions were comfortable. Motor blockade was assessed using the Bromage criteria. Patients were asked if they experienced either pruritus or nausea on a four-point scale (none, mild, moderate, severe). The mean cervical dilatation at placement of the spinal medication was 6.1 ± 2.2 cm. Thirty-two patients had spontaneous vaginal delivery, two were delivered by outlet forceps, and four by Caesarean section. Onset of analgesia was rapid (< five minutes) in all cases. Twenty-three patients (60%) delivered vaginally with no additional anaesthetic. The remaining 15 had supplemental local anaesthetic given via the epidural catheter, a mean of 123 ± 33 min after the original spinal dose. Side effects were limited to pruritus in eight (21%) patients, and mild lower extremity motor weakness in one patient. One patient experienced transient hypotension. No patient developed postdural puncture headache. This technique allows for profound analgesia with a rapid onset and few bothersome side effects. In particular, the absence of motor blockade may facilitate maternal expulsive efforts or positioning during the second stage of labour.     

Lateral popliteal sciatic nerve block compared with ankle block for analgesia following foot surgery

The purpose of this study was to compare postoperative analgesia after foot surgery in patients anaesthetised either with popliteal sciatic nerve block or ankle block. In a prospective study, 40 patients scheduled for foot surgery involving osteotomies were allocated randomly into one of two groups. Following induction of general anaesthesia, Group PS (n = 21) received a lateral popliteal sciatic nerve block and Group AB (n = 19) received an ankle block. Both groups received 20 ml bupivacaine 0.5% plain. In group PS 43% required morphine analgesia in the Post Anaesthetic Recovery Room (PAR) compared with 16% in group AB. Postoperative analgesia was assessed using VAS and a pain scale in the PAR and a questionnaire by telephone follow-up on the day after surgery. The ankle block appeared to be more reliable, providing more consistent analgesia in the PAR. Postoperative analgesia in Group PS lasted a median of 18.0 hr and in Group AB lasted 11.5 hr (P < 0.05). Both techniques provided effective analgesia after discharge home and high levels of patient satisfaction.     

Post-dural puncture thoracic pain without headache: relief with epidural blood patch

We report two unusual cases of postural, post-dural puncture upper thoracic interscapular backache, without headache, that were relieved by epidural blood patching. There is controversy concerning the aetiology of headache associated with the post-dural puncture syndrome. Mechanisms previously proposed have included traction on pain-sensitive intracranial structures such as the dura or blood vessels, or a vascular mechanism which may be adenosine-receptor mediated. These two cases suggest that traction on cervical or upper thoracic nerve roots should be considered as a possible mechanism of pain in the post-dural puncture syndrome. Nous décrivons deux cas de douleurs posturales dorso-thoraciques interscapulaires consécutives à une perforation de la dure-mère sans céphalée mais soulagées par un blood patch. L’étiologie de la céphalée consécutive à la perforation de la dure-mère n’est pas complètement élucidée. Les mécanismes déjà proposés comprennent la traction sur les structures intracraniennes sensibles à la douleur comme la dure-mère et les vais-seaux sanguins ou un mécanisme vasculaire transmis par les récepteurs de l’adénosine. Ces deux observations suggèrent que la traction exercée sur les racines nerveuses cervicales ou thoraciques hautes devrait être considérée comme un mécanisme potentiel de la douleur du syndrome post-perforation duremèrienne.     

Bupivacaine 0.1% does not improve postoperative epidural fentanyl analgesia after abdominal or thoracic surgery

Epidural infusions of fentanyl, in a 10 micrograms.ml-1 concentration, combined with bupivacaine 0.1% were compared with epidural infusions of fentanyl alone for postoperative analgesia following abdominal or thoracic surgery. There were no detectable differences between the two groups in analgesia (mean visual analogue scale pain scores ranging between 15-35 mm), average infusion rates of 7-9 ml.hr-1, and serum fentanyl concentrations which reached 1-2 ng.ml-1. There was no difference in postoperative pulmonary function (pH, PaCO2, SaO2), or bowel function (time to flatus or po fluids). The incidence of side-effects including somnolence, nausea and vomiting, pruritus and postural hypotension was also similar. Of the patients receiving fentanyl and bupivacaine 0.1%, three developed a transient unilateral sensory loss to pinprick and ice, and two of these patients had unilateral leg weakness equal to a Bromage 1 score. The addition of bupivacaine 0.1% does not improve epidural infusions of fentanyl using a 10 micrograms.ml-1 concentration following abdominal or thoracic surgery.     

Posture and the spread of hyperbaric bupivacaine in parturients using the combined spinal epidural technique

This study was undertaken to analyze the effect of posture on the spread of hyperbaric bupivacaine in pregnant women using a combined spinal extradural technique, and to assess the quality of analgesia provided by 10 mg bupivacaine when using this technique. Fifty parturients undergoing elective Caesarean section under regional anaesthesia were randomly allocated to receive 2.0 ml hyperbaric bupivacaine 0.5% in either the sitting or left lateral position. Spinal injection was performed with a 27 gauge, 120 mm long spinal needle using a single space combined spinal extradural technique. The onset time to analgesia at T₄, and grade 3 motor block was on average 7.7 min and 6.9 min respectively in the lateral group, compared with 10.8 min (P < 0.05) and 9.4 min (P < 0.05) in the sitting group. Nine women in the sitting group and one woman (P < 0.05) in the lateral group required epidural supplementation. Hypotension occurred in 48% of the parturients in the lateral group and in 13% (P < 0.05) of the parturients in the sitting group. Nausea was noted in 61% of the parturients in the lateral group and in 22% (P < 0.05) of the parturients in the sitting group. There was no difference between the two groups in neonatal outcome. Overall, the position of the patient during induction of spinal anaesthesia does influence the rate of onset of analgesia and motor blockade. Injection of 10 mg hyperbaric bupivacaine in the sitting position would not provide adequate analgesia for Caesarean section when using a single space combined spinal extradural technique.     

Epidural sufentanil for post-Caesarean section analgesia: lack of benefit of epinephrine

Epidural sufentanil was administered to 57 women after Caesarean section, under epidural anaesthesia, to provide postoperative analgesia. Each patient received a 30 μg dose at the first complaint of pain and this dose was repeated when pain recurred. Epinephrine (1:200,000) was added to the local anaesthetic, sufentanil, both, or neither. The time of onset of analgesia, efficacy, duration of analgesia and the incidence of side-effects were recorded. This dose of epidural sufentanil provided satisfactory postoperative analgesia and no serious side-effects were observed. The onset of analgesia was rapid (4–6 min), but the duration of action was brief (4–5 hr). The addition of 1:200,000 epinephrine had no statistically significant influence on any of the measured variables. Pruritus occurred commonly but never required treatment. Drowsiness was experienced frequently and was felt by some patients to inhibit their interaction with their neonates. Respiratory depression, as defined by a respiratory rate less than 10 bpm, was not observed. A number of patients noted a transient period of euphoria 5–8 min after administration of the epidural sufentanil. The authors feet that epidural sufentanil provides satisfactory analgesia after Caesarean section, but the brief duration of action and the high incidence of drowsiness limit its acceptability for routine use in obstetric patients. Le sufentanil en injection epidurale fut administré à 57 femmes après césarienne pour l’analgésie postopératoire. Chaque patiente a recu 30 μg lors de la première douleur et cette dose fut répétée quand la douleur est revenue. L’épinéphrine (1:200,000) fut ajouté à l’anesthésie locale, le sufentanil, au deux, ou à aucun. Le temps d’installation d’analgésie, l’efficacité, la durée de l’analgésie et l’insuffisance des effets secondaires furent enregistrés. Cette dose de sufentanil en injection épidurale a fourni une analgésie postopératoire satisfaisante et aucun effet secondaire fut observé. Le début de l’analgésie fut rapide (4–6 min), mais la durée d’action fut brève (4–5 hre). L’addition de 1:200,000 épinéphrine n’a eu aucune influence statistiquement significative sur aucune des mesures éludiées. Le prurit fut le plus communément observé mais n’a jamais requis un traitement. La somnolence fut observée fréquemment et certaines patientes l’attachait en la diminution de leur interaction avec les nouveau-nés. La dépression respiratoire définie par une fréquence respiratoire inférieure à 10 resp/min ne fut pas observée. Un certain nombre de patientes out noté une période transitoire d’euphorie de cinq à huit minutes après l’administration de sufentanil en injection épidurale. Les auteurs pensent que le sufentanil en injection épidurale fournit une analgésie satisfaisante après une césarienne mais une durée d’action courte et la haute incidence de somnolence limitent son acceptabilité de routine pour les patientes en obstétrique.

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This study was supported by a grant from Janssen Pharmaceutica.     

Uterine and umbilical blood flow velocity during epidural anaesthesia for Caesarean section

The purpose of this study was to use colour Doppler to determine the effect of epidural anaesthesia on the uterine and umbilical blood flow velocities. After determining the precision of the technique, Doppler insonation of the uterine and umbilical arteries was performed in consenting non-labouring patients requesting epidural anaesthesia for Caesarean section. Patients in Group I were normal and those in Group II were at high risk for uteroplacental blood flow abnormalities. The pulsatility indexes (PI) of both uterine and umbilical arteries were compared at the following times: control, after fluid and after anaesthesia using repeated measure analysis of variance. In Group I (n = 30) the PI increased from 0.72 to 0.82 in the left uterine artery and from 0.71 to 0.85 in the right uterine artery (P < 0.05). In Group II (n = 10) the PI increased from 0.67 to 0.85 in the left uterine artery (NS) and from 0.98 to 1.38 in the right uterine artery (P < 0.05). There was no change in the PI in the umbilical artery. We conclude that the PI of the uterine arteries increases after epidural anaesthesia with lidocaine, epinephrine and fentanyl but there is no change in the umbilical PI. While these changes do not appear to be clinically important in the low-risk population, further studies are required to determine the impact on fetuses at high risk for in utero hypoxaemia.     

Onset of vecuronium neuromuscular block is more rapid in patients undergoing Caesarean section

This investigation was carried out in ten patients undergoing elective Caesarean section and the results were compared with those of a control group of ten nonpregnant females of the same age group. The study investigated the onset of vecuronium neuromuscular block and the conditions of tracheal intubation when ketamine (1.5 mg.kg-1)-vecuronium 100 micrograms.kg-1) sequence was used for rapid-sequence induction of anaesthesia. The ulnar nerve was stimulated supra-maximally at the wrist with train-of-four stimuli every 20 sec, and the electromyographic response of the adductor pollicis muscle was displayed. The onset of 50% neuromuscular block as monitored by electromyography was shorter in the Caesarean group (80 +/- 30 sec) than in the control group (144 +/- 43 sec). The conditions of intubation at 50% block were adequate in both groups. Also, the onset of 90% block was shorter in the Caesarean group. The time of recovery to T1/control ratio of 25% was longer in the Caesarean group (46 +/- 10 min) than in the control patients (28 +/- 10 min). The results show that administration of vecuronium according to body weight results in a more rapid onset and delayed recovery of neuromuscular block in pregnant women undergoing Caesarean section than in the nonpregnant control patients.     

Autonomic hyperreflexia during labour

We present two cases of automatic hyperreflexia (AH) during labour in women with spinal cord damage, in whom AH developed before and after delivery. The AH was successfully controlled using epidural anaesthesia in Case #1, but failed in Case #2. The blood pressure was controlled with nicardipine. However, overdose of nicardipine produces vasodilatation and its side effects include headache, flushing and palpitation similar to AH¹. Considering these effects, we recommend epidural anaesthesia to control AH, because epidural anaesthesia does not only reduce BP, but also blocks the noxious stimuli and relieves the symptoms of AH. Our experience suggests that the epidural catheter can be placed two to three weeks before the date of predicted childbirth, because the onset of labour in a patient with spinal cord damage is difficult to predict and can proceed very rapidly. Also, the epidural catheter is available after the delivery. We recommended the epidural catheter is maintained for 24–48 hr postpartum.