Increased oxygen administration during awake carotid surgery can reverse neurological deficit following carotid cross-clamping

We describe the management of two patients undergoing awakecarotid surgery who developed signs of cerebral ischaemia followingcross-clamping of the internal carotid artery. Administrationof oxygen 100% with a close-fitting anaesthetic facemask reversedthe neurological deficit, avoiding the need for insertion ofan internal carotid artery shunt. Thus, the incidence of shuntinsertion, which is reduced by the use of regional rather thangeneral anaesthesia, could be reduced further by supplementaryoxygenation. The possible mechanism and implications are discussed.     

Comparison between instillation of bupivacaine versus caudal analgesia for postoperative analgesia following inguinal herniotomy in children

BACKGROUND: In this study we compare the postoperative pain relief for inguinal herniotomy in children provided by instillation of bupivacaine into the wound with that provided by a caudal block. METHODS: Fifty-eight children aged 0-5 years having elective unilateral hernia repair were studied in this prospective, randomized, single-blind study. Anaesthesia was induced and maintained with oxygen, nitrous oxide, sevoflurane and propofol. Patients were randomly assigned to receive caudal analgesia with 1.0 ml.kg-1 body weight (BW) bupivacaine 0.25% or wound instillation with 0.2 ml.kg-1 BW bupivacaine 0.5% at the end of surgery. Pain was assessed over 24 h using a modified 10-point objective pain scale. During the first postoperative hour in the postanaesthesia care unit (PACU), intravenous (i.v.) piritramide (0.05 mg.kg-1) was administered to any child scoring 5 or more points on the pain scale. On the ward, rectal acetaminophen was administered by a staff nurse when considered necessary. RESULTS: Thirty children in the caudal group and 28 children in the wound instillation group were studied. There were no statistically significant differences between the groups regarding need for i.v. opioids, discharge time from the PACU and administration of acetaminophen. No statistically significant differences in postoperative pain score were observed in 16 of a total of 17 postoperative observations. No complications and no adverse effects were observed. CONCLUSION: Instillation of bupivacaine into a wound provides postoperative pain relief following hernia repair, which is as effective as that provided by a postoperative caudal block.     

The effect of the addition of adrenaline to pethidine for patient-controlled epidural analgesia after Caesarean section

We have investigated the addition of adrenaline to pethidine for patient-controlled epidural analgesia after elective Caesarean section. In a randomised, double-blind study, patients received patient-controlled epidural analgesia for 24 h using pethidine 5 mgml⁻¹ with adrenaline 5 μgml⁻¹ (adrenaline group, n  = 40) or pethidine 5 mgml⁻¹ without adrenaline (plain group, n  = 38). Visual analogue scale pain scores at rest and on coughing measured 2 h, 6 h and 24 h after surgery were similar between the two groups. There was a trend towards lower mean total consumption of pethidine in the adrenaline group (231.5 mg; SD 140.5 mg) compared with the plain group (289.5 mg; SD 139.5 mg; p = 0.071). Patients in the adrenaline group had higher visual analogue scale scores for nausea at 2 h and 24 h and higher scores for pruritus at 2 h compared with the plain group. Addition of adrenaline to pethidine for patient-controlled epidural analgesia does not appear to have significant clinical advantages.     

Performance of the On-Q pain infusion device during changes in environmental temperature

Background: The On‐Q infusion device is an elastomeric device with a flow regulator that controls the flow of a local anesthetic agent through a peripheral catheter. As variations in external temperature may affect the diameter of the tubing or viscosity of the fluid, it is feasible that alterations in flow may be caused by such temperature variations. This study evaluates the performance of this device during variations in environmental temperature. Methods: The disposable 400 ml On‐Q pain ball infusion devices were filled and connected to a single, end hole infusion catheter and set to infuse at 14 ml·h^?1. Eighteen devices were used in the study (six of each at three different temperatures). The temperatures included hot (54°C), room temperature (21°C), and cold (6°C). The devices were allowed to flow for 24 h. The fluid delivered during each 12‐h period was measured using a graduated column. Results: There were significant differences in the output from the devices at the hot (54°C) temperature and the cold (6°C) temperature when compared to room temperature (21°C). When compared to room temperature, the output decreased to 67% and 54% of the control group (room temperature) during hours 0–12 and 12–24, respectively, in a cold environment (6°C). An increased external temperature resulted in a greater output from the devices. When compared to the room temperature devices, the output was 49% higher during the first 12 h and 40% higher during the second 12 h at an external temperature of 54°C. Conclusions: This preliminary investigation demonstrates what may be clinically significant changes in output from the On‐Q pain device based on the external temperature. These alterations in flow could result in inadequate analgesia or even potentially toxicity if these devices are used in smaller patients especially the pediatric population.     

Analgesic efficacy of bilateral superficial cervical plexus block administered before thyroid surgery under general anaesthesia

Background: The use of regional anaesthesia in thyroid surgery remains controversial.This double-blind, randomized controlled study was conductedto evaluate the analgesic efficacy of bilateral superficialcervical plexus block (BSCPB) performed under general anaesthesiain patients undergoing total thyroidectomy. Methods: Eighty-seven consecutive consenting patients were randomizedto receive a BSCPB with saline (Group P, n = 29), ropivacaine0.487% (Group R, n = 29), or ropivacaine 0.487% plus clonidine5 µg ml^–1 (Group RC, n = 29). Sufentanil was givenduring the intraoperative period for a 20% increase in arterialmean pressure or heart rate in a patient with a bispectral indexbetween 40 and 60. All patients received 4 g of acetaminophenduring the first 24 h after operation. The pain score was checkedevery 4 h and nefopam was given for pain score >4 on a numericpain scale. Results: During surgery, the median sufentanil requirements were significantlyreduced in Group RC compared with Groups R and P (0.32 vs 0.47and 0.62 µg kg^–1; P < 0.0001). After surgery,the number of patients requiring nefopam within 24 h of surgerywas significantly lower in Groups R and RC than in Group P (16and 19 vs 25; P = 0.03). At post-anaesthetic care unit admission,median (range) pain scores were significantly lower in GroupsR [3 (0–10)] and RC [3 (0–8)] than in Group P [5(0–8), P = 0.03]. No major complications of BSCPB occurredduring study. Conclusions: BSCPB with ropivacaine and clonidine improved intraoperativeanalgesia. BSCPB with ropivacaine or ropivaciane and clonidinewas effective in reducing analgesic requirements after thyroidsurgery.     

Epidural analgesia compared with peripheral nerve blockade after major knee surgery: a systematic review and meta-analysis of randomized trials

The relative analgesic efficacy and side-effect profile of peripheral nerve blockade (PNB) techniques compared with lumbar epidural analgesia for major knee surgery is unclear. We undertook a systematic review and meta-analysis of all randomized trials comparing epidural analgesia with PNB for major knee surgery. Eight studies were identified that had enrolled a total of 510 patients of whom 464 (91%) had undergone total knee joint replacement. All were small trials and none was blinded (Jadad score 1-3). PNB technique was variable: in addition to a femoral catheter (n=5), femoral single shot (n=2), or lumbar plexus catheter (n=1) techniques, sciatic blockade was performed in three trials. There was no significant difference in pain scores between epidural and PNB at 0-12 or 12-24 h, WMD 0.22 (95% CI: -0.36, 0.81), 0.05 (-1.01, 0.91), respectively, and no clinically significant difference at 24-48 h, WMD -0.35 (-0.64, -0.02). There was also no difference in morphine consumption (mg) at 0-24 h, WMD -6.25 (-18.35, 5.86). Hypotension occurred more frequently among patients who received epidurals [OR 0.19 (0.08, 0.45)], but there was no difference in the incidence of nausea and vomiting. Two studies reported a higher incidence of urinary retention in the epidural group. Patient satisfaction was higher with PNB in two of three studies which measured this, although rehabilitation indices were similar. PNB with a femoral nerve block provides postoperative analgesia which is comparable with that obtained with an epidural technique but with an improved side-effect profile and is less likely to cause a severe neuraxial complication.     

Anaesthesia-related diplopia after cataract surgery

Background. We studied the incidence and clinical characteristicsof persistent diplopia related to anaesthesia for cataract surgeryin a general hospital. Methods. This was a retrospective review of anaesthesia for3587 cataract surgeries. Of all the cases of diplopia referredto the ocular motility clinic after cataract surgery, thoseinvolving anaesthesia-related diplopia lasting longer than 1month were studied. Results. During the study period, 3450 cataract surgeries wereperformed by phacoemulsification and 137 by extracapsular extraction.Retrobulbar block was used in 2024 cases, peribulbar block in98, topical anaesthesia in 1420 and general anaesthesia in 43.Twenty-six cases of persistent diplopia were found (0.72% incidence),nine of which (0.25%) were considered to be related to anaestheticfactors; five of the latter involved the left eye. Five werecaused by paresis of the inferior rectus muscle and three byfibrosis. In one patient, the inferior oblique muscle was affected.Anaesthesia was by retrobulbar block in eight cases (0.39%)and by peribulbar block in one. No diplopia was found in patientswho had topical or general anaesthesia. Treatment was with surgeryin two patients and with prisms in six. One patient continuesto be studied. Conclusions. Persistent diplopia can occur after cataract surgeryusing retrobulbar block predominantly through direct damageto the inferior rectus muscle. The overall incidence of anaesthesia-relateddiplopia in this series was 0.25%. Br J Anaesth 2003; 90: 189–92     

Comparison of continuous spinal and continuous epidural anaesthesia for lower limb surgery in elderly patients A retrospective study

This retrospective study compared continuous spinal anaesthesia with continuous epidural anaesthesia for lower limb orthopaedic surgery in the elderly. The anaesthetic records of 457 patients who received continuous spinal anaesthesia and 274 who received continuous epidural anaesthesia over a 5-year period were analysed. The patients who had continuous spinal anaesthesia were at a higher anaesthetic risk (ASA 3-4, 76% as compared with 37%, p less than 0.001), but the incidence of failures was significantly lower (1.7%, as compared with 9%, p less than 0.001) and fewer patients showed a decrease in mean arterial pressure of more than 30% (44%, as compared with 65%, p less than 0.001) and (or) received vasopressors (65%, as compared with 77%, p less than 0.01). Our data show continuous spinal anaesthesia to be more reliable and to provide better cardiovascular stability.     

Quinine poisoning

The treatment of a case of quinine amblyopia by stellate ganglion blockade is described. The degree of restoration of vision confirms the experience of other workers and is attributable to relief of retinal vasoconstriction. The possibility is discussed that earlier and more prolonged use of the technique might improve results.     

Temporary trigeminal disorder as a result of pneumocephalus after subarachnoid block

A patient was scheduled for inguinal herniorrhaphy under subarachnoidblock. Lumbar puncture was difficult and several attempts wereneeded before it could be achieved. During the immediate postoperativeperiod, the patient developed paraesthesia and anaesthesia onthe right side of the face, mostly in the nose, cheek and upperlip areas. A CT scan showed a small pneumocephalus at the levelof the brainstem. The symptoms persisted for approximately 70min, after which they disappeared. Br J Anaesth 2003; 91: 430–2     

Superficial or deep cervical plexus block for carotid endarterectomy: a systematic review of complications

Carotid endarterectomy is commonly conducted under regional(deep, superficial, intermediate, or combined) cervical plexusblock, but it is not known if complication rates differ. Weconducted a systematic review of published papers to assessthe complication rate associated with superficial (or intermediate)and deep (or combined deep plus superficial/intermediate). Thenull hypothesis was that complication rates were equal. Complicationsof interest were: (1) serious complications related to the placementof block, (2) incidence of conversion to general anaesthesia,and (3) serious systemic complications of the surgical-anaestheticprocess. We retrieved 69 papers describing a total of 7558 deep/combinedblocks and 2533 superficial/intermediate blocks. Deep/combinedblock was associated with a higher serious complication raterelated to the injecting needle when compared with the superficial/intermediateblock (odds ratio 2.13, P = 0.006). The conversion rate to generalanaesthesia was also higher with deep/combined block (odds ratio5.15, P < 0.0001), but there was an equivalent incidenceof other systemic serious complications (odds ratio 1.13, P= 0.273; NS). We conclude that superficial/intermediate blockis safer than any method that employs a deep injection. Thehigher rate of conversion to general anaesthesia with the deep/combinedblock may have been influenced by the higher incidence of directcomplications, but may also suggest that the superficial/combinedblock provides better analgesia during surgery.     

Efficacy of varying concentrations of hyaluronidase in peribulbar anaesthesia

We have compared the efficacy of adding varying concentrationsof hyaluronidase to a standard mixture of 2% lidocaine and 1%ropivacaine to provide peribulbar anaesthesia for cataract surgery.We used (i) the time to adequate anaesthesia for surgery and(ii) ocular and eyelid movement scores at 8 min after blockas clinical endpoints. Ninety patients were randomly allocatedto receive 7–10 ml of equal volumes of 2% lidocaine and1% ropivacaine without hyaluronidase or with hyaluronidase 15IU ml^–1or 150 IU ml^–1. Median time at which theblock was adequate for surgery was 6 min in all groups (interquartilerange 4–12 min). Median eyelid movement scores were similarin all groups, but the ocular movement scores at 8 min weresignificantly lower in the group which received hyaluronidase150 IU ml^–1 than in the group not given hyaluronidase(P<0.03). There were no differences between groups in theincidence of minor complications. A high concentration of hyaluronidaseresulted in a statistically significantly lower ocular movementscore at 8 min; the clinical relevance of this finding is uncertain. Br J Anaesth 2001; 86: 876–8     

Early exploration of diplopia with magnetic resonance imaging after peribulbar anaesthesia

We report the cases of five patients who have experienced postoperativediplopia after cataract surgery under peribulbar anaesthesiaand in whom orbital Magnetic Resonance Imaging was performedimmediately after the diagnosis. In four patients, the imagingstudy showed a T2 hyper-intensity signal and swelling of oneextraocular muscle that was interpreted as oedema. Therefore,these cases were most probably a result of an accidental i.m.injection of local anaesthetics. In the other patient, the imagingstudy revealed no abnormality. Br J Anaesth 2004; 92: 899–901     

Thigh abscess as a complication of continuous popliteal sciatic nerve block

We present a case report of severe localized infection aftercontinuous popliteal sciatic nerve block. The report highlightsthe importance of meticulous asepsis and possibly limiting theduration of catheter use.     

Epidural infusion or combined femoral and sciatic nerve blocks as perioperative analgesia for knee arthroplasty

Background. Peripheral neural blockade appears to provide effectiveanalgesia with potentially less morbidity than central neuraxialtechniques. We compared the relative benefits of combined femoral(3-in-1) and sciatic nerve block with epidural blockade forpostoperative knee arthroplasty analgesia. Methods. Sixty patients, ASA I–III, undergoing unilateralknee replacement were prospectively randomized to receive eithera lumbar epidural infusion or combined single-shot femoral (3-in-1)and sciatic blocks (combined blocks). All patients receivedstandard general anaesthesia. Visual analogue pain scores andrescue opioid requirements were recorded at four time pointspostoperatively. Patient satisfaction, morbidity, block insertiontime, perioperative blood loss and rehabilitation indices werealso assessed. Results. In both groups, pain on movement was well controlledat discharge from recovery and 6 h postoperatively but increasedat 24 and 48 h. Median (95% CI) analogue scale scores were 0(0–0), 15 (0–30), 55 (38–75) and 54 (30–67)mm for epidural block and 0.5 (0–22), 21.5 (10–28),40 (20–50) and 34.5 (21–55) mm for combined block.VAS pain scores with the combined blocks were significantlylower at 24 h (P=0.004). Total morphine usage was low in bothgroups: median epidural group 17 mg (8–32) versus combinedblocks 13 mg (7.8–27.5). Patient satisfaction was highin both groups with median (95% CI) scores of 100 (85–100),83 (70–100) and 82 (57–90) mm for epidural and 90(73–100), 100 (77–100) and 97 (80–100) mmfor combined blocks (not significant). Perioperative blood lossand rehabilitation indices were also similar. Conclusions. Combined femoral (3-in-1) and sciatic blocks offera practical alternative to epidural analgesia for unilateralknee replacements.      

颈胸交感神经的解剖及临床意义

目的 通过对颈、胸交感神经的大体和显微解剖,观察交感神经的位置与毗邻关系,为临床治疗提供依据.方法 对30具60侧成人尸体标本作解剖学研究,观察其与周围相邻组织结构的关系和位置,以及交感神经节之间的联系.结果 颈交感干与椎动脉、臂丛神经存在广泛交通支;上胸段交感神经多位于相应的肋间,随着节段下移,出现在下位肋骨上缘或者表面的几率逐渐增高.颈胸交感神经节之间还存在额外的交通支.结论 切除交感神经可治疗由交感神经过度兴奋引起的多种病症,但切除的范围难以确定.颈胸交感神经节之间可能存在相互代偿作用,相互影响.