Epidural pressure and its relation to spread of epidural analgesia

The relationships between the epidural pressures following the injection of local anesthetic solution and the spread of epidural analgesia were investigated. In 46 patients, 15ml of 2% mepivacaine was injected into the lumbar epidural space at a constant rate (1ml/sec) using an electropowered syringe pump. Injection pressures and residual pressures were recorded and the spread of analgesia to pinprick was assessed. The changes of the epidural pressures during and following the injection of a volume of local anesthetic solution in old subjects were significantly smaller than those in young subjects (P < 0.05). The spread of analgesia closely correlated with the epidural pressures during and following the injection of local anesthetic solution. The most close correlation was found between the epidural pressure immediately after the completion of injection and the spread of analgesia (r = –0.5659, P < 0.001). In conclusion, the lower the terminal injection pressure and the residual pressures associated with higher age, the wider the spread of epidural analgesia.(Hirabayashi Y, Matsuda I, Inoue S et al.: Epidural pressure and its relation to spread of epidural analgesia. J Anesth 1: 168–172, 1987)     

Puerperal ventral epidural hematoma after epidural labor analgesia

Serious complications in obstetric anesthesia are a rare occurrence. High neuraxial block, respiratory arrest in labor and delivery, and an unrecognized spinal catheter are among the most frequently reported serious complications. A serious complication occurs in approximately 1:3 000 obstetric patients. Neuraxial hematoma after obstetric epidural analgesia or anesthesia is extremely rare.We present a case of a puerperal spinal epidural hematoma following epidural labor analgesia. The patient presented with foot drop, which resolved after conservative treatment. We reviewed the epidemiology, clinical manifestations and treatment options for this rare complication.     

程控硬膜外脉冲式注射或连续硬膜外输注复合硬膜外自控镇痛用于分娩镇痛的比较

目的评价不同间隔时间行程控硬膜外脉冲式注射(programmed intermittent epidural bolus,PIEB)或连续硬膜外输注(continuous infusion epiduaral,CEI)复合PCEA用于分娩镇痛的效果。方法选择有分娩镇痛要求的足月初产妇186例,ASAⅠ或Ⅱ级,采用数字表法随机分为三组,每组62例。三组均使用首次剂量(0.125%罗哌卡因+0.4μg/ml舒芬太尼)10 ml,镇痛泵均使用(0.08%罗哌卡因+0.4μg/ml舒芬太尼)100ml。PIEB1组(P1组):5ml/30min,首次剂量注入30min后开始脉冲给药;PIEB2组(P2组):10 ml/60 min,首次剂量注入60 min后开始脉冲给药;CEI组(C组):10ml/h,首次剂量注入后立即开始持续给予背景剂量。三组均设置PCA量5ml,锁定时间30min。记录镇痛期间宫缩疼痛VAS评分、运动阻滞程度Bromage评分、VAS评分3分的例数和(MBS)评分1分的例数;记录最高感觉阻滞平面、镇痛药物用药总量、催产素使用量、PCEA按压次数,第一次追加药物时间、产程时间、分娩方式和产间发热的例数;记录不良反应的发生情况。结果三组在分娩镇痛开始后VAS评分均明显低于镇痛前,P2组VAS3分的比率明显低于P1组和C组(P0.05)。镇痛期间,P1组最高感觉阻滞平面明显高于P2组和C组,P2组单侧阻滞发生率明显低于C组(P0.05)。P2组镇痛药物用药总量、PCEA按压次数明显少于,第一次追加药物时间明显长于P1组和C组(P0.05)。P1组与P2组器械助产与产间发热的例数明显少于C组(P0.05)。结论在分娩镇痛中给予首次剂量后,间隔60min行PIEB模式注射技术,是一种更有效的给药方法。     

Thoracic epidural anaesthesia and analgesia: United Kingdom practice

BACKGROUND: Thoracic epidural analgesia has become increasingly practised in recent years. Complications are rare but potentially serious and, consequently, careful evaluation is required before undertaking this technique. The practice surrounding this procedure varies widely amongst anaesthetists. METHODS: A postal survey to examine the practice of thoracic epidural analgesia was sent to all Royal College of Anaesthetists tutors in the United Kingdom. RESULTS: Responses were received from 240 tutors, representing a return rate of 83%. When obtaining consent for thoracic epidural cannulation, 42% of respondents mentioned risk of a dural tap complication and 11% mentioned neurological damage. Fifty percent of respondents performed epidural cannulation following induction of general anaesthesia. The practice of epidural insertion in patients with abnormal coagulation varied, although over 80% of respondents did not consider concurrent treatment with either aspirin or non-steroidal anti-inflammatory drugs a contraindication. Sterile precautions for epidural insertion also varied between anaesthetists. Postoperatively, 95% of respondents used an opioid-based bupivacaine solution for epidural infusions, and these were most commonly nursed on general surgical wards (63%). Seventy-eight percent of hospitals provided an acute pain team to review epidural analgesia. CONCLUSION: In the United Kingdom, there is little consensus in the practice of thoracic epidural analgesia relating to the issues of informed consent, epidural cannulation in patients with deranged clotting and the sterile precautions taken prior to performing epidural insertion. Most respondents use an opioid-based bupivacaine solution to provide postoperative epidural analgesia. Most hospitals in the UK now provide an acute pain service for thoracic epidural follow-up.     

Complications related to thoracic epidural analgesia: a prospective study in 1071 surgical patients

In a prospective study, the complications of 1071 patients scheduled for thoracic epidural catheterization for postoperative analgesia (TEA) were studied. All catheters were inserted preoperatively between segment Th 2/3 and Th 11/12 under local anesthesia. Balanced anesthesia with endotracheal intubation and TEA were combined. Postoperatively 389 patients (36.9%) were monitored on a normal surgical ward. Buprenorphine, 0.15 to 0.3 mg, and if needed bupivacaine 0.375% 3–5 ml h^-1 were given epidurally. Primary perforation of the dura occurred in 13 patients (1.23%). Radicular pain syndromes were observed in six patients (0.56%). In one patient (0.09%) respiratory depression was seen in close connection with the epidural administration of 0.3 mg buprenorphine. Although 116 patients (10.83%) showed one abnormal clotting parameter but no clinical signs of hemorrhage, there was no complication related to this group. No persisting neurological sequelae caused by the thoracic epidural catheters were found. In conclusion, continuous TEA with buprenorphine for postoperative pain relief after major abdominal surgery is a safe method without too high a risk of catheter-related or drug-induced complications, even on a normal surgical ward and when one clotting parameter is abnormal.     

Automated regular boluses for epidural analgesia: a comparison with continuous infusion

BACKGROUND: Intermittent epidural bolus dosing is a method of drug delivery that can prolong the duration of labour analgesia induced by a combined spinal epidural (CSE). In this randomized, double-blinded study, we compared the analgesic efficacy of two drug delivery systems: regular intermittent epidural boluses and continuous epidural infusion and assessed the incidence of breakthrough pain after CSE. METHODS: With the approval of the Hospital Ethics Committee, we recruited 60 parturients into this randomized controlled trial. A CSE was performed with intrathecal fentanyl 25 mug in all patients. The parturients were then randomly allocated into two groups. The infusion group received a continuous epidural infusion of levobupivacaine 0.1% with fentanyl 2 microg/mL at a rate of 10 mL/h. The bolus group received 5-mL epidural boluses every half hour. The sample size was computed to detect a 40% reduction in the rate of breakthrough pain. RESULTS: The bolus group had a lower incidence of breakthrough pain than the infusion group (10% vs. 37%, P < 0.05). The bolus group also had significantly higher satisfaction scores for labour analgesia: 97+/-8 (mean+/-SD) vs. 89+/-7 (P < 0.05). CONCLUSION: Automated regular bolus delivery of epidural analgesia when compared with continuous infusion decreased the incidence of breakthrough pain and increased maternal satisfaction. In a busy obstetric unit, this may also serve to decrease the anesthetists' workload.     

硬膜外间歇脉冲注入技术用于分娩镇痛的效果

目的 探讨硬膜外间歇脉冲注入技术（PIEB）在产妇自控硬膜外分娩镇痛中的效果及对分娩结局的影响。
方法 选择行硬膜外分娩镇痛的单胎、头位、足月妊娠产妇100例,年龄18～38岁,BMI 20～32 kg/m²,ASA Ⅰ或Ⅱ级,采用随机数字表法分为两组：PIEB组和连续硬膜外输注组（CEI组）,每组50例。两组镇痛药配方均为0.08％罗哌卡因＋0.4 μg/ml舒芬太尼。PIEB组参数设置：脉冲频率每小时1次,剂量10 ml,注药速率400 ml/h,单次剂量10 ml,间隔20 min。CEI组参数设置：背景输注速率10 ml/h,单次剂量10 ml,间隔20 min。记录产妇分娩镇痛前、镇痛后1、2、3、5 h、宫口开全和分娩时的VAS疼痛评分;产妇首次按压时间、按压次数、镇痛泵用药总量、镇痛时间;总产程时间、产后出血量、新生儿Apgar评分、产妇对分娩镇痛效果满意度评分;感觉阻滞平面达T4的例数、改良Bromage评分;以及低血压、恶心呕吐等不良反应发生情况。
结果 与分娩镇痛前比较,分娩镇痛后两组产妇VAS疼痛评分明显降低（P<0.05）。与CEI组比较,PIEB组镇痛后2、3、5 h、宫口开全、分娩时VAS疼痛评分均明显降低（P<0.05）,首次按压时间明显延迟（P<0.01）,按压次数、镇痛泵用药总量明显减少（P<0.01）。与CEI组比较,PIEB组产妇满意度评分明显增高（P<0.01）,感觉阻滞平面达T4的产妇比例明显升高（P<0.05）。两组总产程时间、产后出血量、新生儿Apgar评分差异无统计学意义。两组低血压和恶心呕吐等不良反应发生率差异无统计学意义。
结论 PIEB可安全有效地用于产妇自控硬膜外分娩镇痛,其效果优于连续硬膜外输注,产妇满意度高,且不影响分娩结局。     

Effect of preemptive epidural analgesia on cytokine response and postoperative pain in laparoscopic radical hysterectomy for cervical cancer

BACKGROUND AND OBJECTIVE: Surgical stress and general anesthesia suppress immune function. Preemptive epidural analgesia can affect the perioperative immune responses, and influence cancer management. METHODS: Forty women undergoing elective laparoscopic radical hysterectomy for cervical cancer were allocated to this prospective, randomized, double-blind trial. Before inducing anesthesia, 2 mg morphine dissolved in 15 mL of 1% lidocaine (preemptive group) or the same volume of normal saline (control group) was administered into the epidural space through a prepared catheter in a double-blind manner, using sealed syringes. After peritoneal closure, the other drugs in the remaining sealed syringe were administered in the reverse manner. All patients were then administered lidocaine plus morphine over a 72-hour period, using a patient-controlled epidural analgesia pump. RESULTS: The interleukin-6 levels in both groups increased significantly after surgery. These elevations were significantly less pronounced in the preemptive group than in the control group. The interleukin-2 level in both groups decreased significantly after surgery. Seventy-two hours after surgery, the interleukin-2 level returned to its baseline value in the preemptive group but not in the control group. The number of lymphocytes in both groups decreased significantly after surgery. The pain scores at 6 and 12 hours after surgery in the preemptive group were significantly lower than in the control group. CONCLUSIONS: Preemptive epidural analgesia is a reasonable approach for potentially controlling perioperative immune function and preventing postoperative pain in patients undergoing cancer surgery.     

程控硬膜外间歇脉冲注入与持续背景输注用于分娩镇痛的比较

目的比较程控硬膜外间歇脉冲注入(programmed intermittent epidural bolus,PIEB)和持续背景输注(CEI)两种模式联合PCEA用于分娩镇痛的临床效果。方法自愿接受分娩镇痛足月、单胎和头位初产妇200例,随机分为两组,每组100例。在宫口扩张2~3 cm时采用硬膜外阻滞行分娩镇痛。PIEB组背景输注剂量为8 ml/h,给药速度为6 ml/min,每小时给药一次;CEI组以8ml/h的速度持续给药。观察产妇镇痛前(T0)、镇痛后10 min(T1)、30 min(T2)、1 h(T3)、2 h(T4)、宫口开全时(T5)、分娩时(T6)、分娩后1 h(T7)BP、VAS评分、改良Bromage评分;PCEA追加次数、罗哌卡因、舒芬太尼的用量、宫缩情况、胎心率、产程时间、镇痛时间、分娩方式、产妇使用催产素、不良反应、新生儿Apgar评分、产妇满意度评分。结果 T4~T6时PIEB组VAS评分明显低于CEI组(P0.01)。PIEB组PCEA追加次数、药物用量明显少于CEI组(P0.05),PIEB组产妇满意度明显高于CEI组(P0.05)。两组产妇的血压、宫缩持续时间和间隔时间、胎心率、产程、镇痛时间、分娩方式、使用催产素比例、不良反应发生率及新生儿Apgar评分差异无统计学意义。结论与采用CEI+PCEA模式比较,PIEB+PCEA模式的PCEA追加率更低、用药量更少、VAS评分更低、产妇的满意度更高,而不良反应并没有增加。     

低背景剂量联合大剂量PCA在产妇硬膜外分娩镇痛中的应用

目的观察在持续输注联合硬膜外自控给药模式下低背景剂量持续输注联合大剂量PCA的参数设置对分娩镇痛临床效果的影响。方法选择自愿接受分娩镇痛足月、单胎和头位初产妇120例,年龄25~35岁,体重58~86kg,ASAⅠ或Ⅱ级,随机分为两组:常规组(A组)和低背景剂量组(B组)。在宫口扩张2~3cm时采用硬膜外分娩镇痛。每组均事先配置硬膜外注射混合液0.1%罗哌卡因+2μg/ml芬太尼100ml。A组为常规组,背景剂量6ml/h,PCA 5ml,间隔40min;B组为低剂量组,背景剂量2ml/h,PCA 10ml,间隔为40min。记录产妇镇痛前、镇痛后10min、30min、1h、2h、宫口开全时和分娩时VAS评分及改良Bromage评分;记录PCA追加次数;记录爆发痛例数;记录硬膜外混合液的用量;记录镇痛时间、产程时间、分娩方式;记录不良反应的发生情况和新生儿Apgar评分。结果镇痛期间两组产妇VAS评分差异无统计学意义;接受镇痛期间B组混合液用量(40.5±7.5)ml;明显少于A组(60.3±12.0)ml(P0.05);B组PCA实际追加次数(1.6±0.9)次明显少于A组(3.0±1.8)次(P0.05)。两组产妇的产程、镇痛时间、爆发痛例数、不良反应发生率、产妇分娩方式和新生儿Apgar评分差异无统计学意义。结论采用低背景剂量(2ml/h)联合大剂量PCA(10ml,间隔40min)的硬膜外自控镇痛参数设置不仅没有降低镇痛效果,还可减少硬膜外腔用药总量。     

Labor epidural analgesia onset time and subsequent analgesic requirements: a prospective observational single-center cohort study

BackgroundWe investigated the correlation between lumbar epidural analgesia onset time and pain intensity at 60 and 120 min after initiation.MethodsWe conducted a prospective observational study of nulliparous women receiving lumbar epidural analgesia (initial bolus 15 mL bupivacaine 0.1% with fentanyl 3.33 μg/mL), followed by patient-controlled epidural analgesia (PCEA). The measured variable was lumbar epidural analgesia onset time (time to pain numerical rating score ≤3). Secondary outcomes were pain score at 60 and 120 min and at full dilatation; and analgesic requirements through the labor.ResultsOne-hundred-and-five women were eligible for analysis. There was a significant correlation between lumbar epidural analgesia onset time and pain intensity at 60 min (Spearman’s R²=0.286, P=0.003), but not at 120 min (R²=0.030, P=0.76). Women who requested more PCEA boluses during the first 120 min had a longer lumbar epidural analgesia onset time (R²=0.321, P=0.001) and reported higher pain scores at 60 min (R²=0.588, P <0.001) and at 120 min (R²=0.539, P <0.001). Women who reported higher pain scores at 60 min had more pain at 120 min (R²=0.47, P <0.001) and higher analgesic consumption during labor (R²=0.403, P <0.001). Women who were at a greater cervical dilatation at 60 and 120 min had higher pain scores at the same time point (R²=0.259, P=0.008 and R²=0.243, P=0.013 respectively).ConclusionThere was a correlation between the onset time of lumbar epidural analgesia during labor and the pain score 60 min later but this had disappeared by 120 min.     

Paraplegia, a severe complication to epidural analgesia

We report four cases where continuous epidural analgesia resulted in epidural abscesses (EA) causing spinal cord damage and paraplegia. The first symptom of EA was intense back pain, which developed 0-20 days after removal of the epidural catheter. The diagnosis of EA was not made prior to the development of severe neurologic disturbances in any of the patients. In all cases there was a time lag of 2-4 days between the first symptoms and institution of the appropriate treatment.     

Spread of epidural analgesia following a constant pressure injection

(1) The spread of epidural analgesia following injection of 15ml of 2% mepivacaine was 17.3 ± 0.6, 14.3 ± 0.4, and 13.3 ± 0.7 spinal segments in cervical, thoracic, and lumbar epidural analgesia, respectively. The patients age showed significant correlation with the spread of epidural analgesia in cervical (r = 0.5776, p < 0.001), thoracic (r = 0.3758, p < 0.01), and lumbar area (r = 0.8195, p < 0.001). The spread of cervical epidural analgesia was more caudad than cephalad (p < 0.05), but in lumbar epidural analgesia it was more cephalad than caudad (p < 0.05). There was no difference between the cephalad and caudad spread in thoracic epidural analgesia.(2) The epidural pressure immediately after injection of 15ml of 2% mepivacaine into the lumbar epidural space at a constant pressure (80mmHg) correlated to the patients age (r = –0.5714, p < 0.001) and the spread of analgesia (r = –0.3904, p < 0.05). The lower epidural pressure associated with higher age, the wider spread of analgesia. There was no significant correlation between the residual pressure at 60 seconds and the age or the spread of analgesia.(Hirabayashi Y et al.: Spread of epidural analgesia following a constant pressure injection: an investigation of relationships between locus of injection, epidural pressure and spread of analgesia. J Anesth 1: 44–50, 1987)     

Programmed intermittent epidural boluses for maintenance of labor analgesia: an impact study

IntroductionThe aim of this impact study was to compare the analgesic efficacy and side effect profile of programmed intermittent epidural boluses (PIEB) + patient-controlled epidural analgesia (PCEA) to continuous epidural infusion (CEI) + PCEA for maintenance labor analgesia after the introduction of PIEB at our institution.MethodsWe conducted a retrospective analysis after replacing the background CEI with PIEB for our labor PCEA. Pre-change pump settings were CEI 12 mL/h with PCEA (12 mL bolus, lockout 15 min); PIEB settings were a 9 mL bolus every 45 min with PCEA (10 mL bolus, lockout 10 min). We compared medical records of all women receiving epidural or combined spinal-epidural labor analgesia for vaginal delivery for two months before PIEB implementation to a two-month period of PIEB utilization following a five-month introductory familiarization period. The primary outcome was the proportion of women requiring rescue clinician boluses.ResultsFewer patients in the PIEB group required rescue clinician boluses compared to the CEI group (12% vs. 19%, P=0.012). Time to first rescue bolus request and total bolus dose were not different. Peak (median [IQR]) pain scores were 2[0–5] with CEI and 0[0–4] with PIEB. There was no difference in instrumental delivery rates.ConclusionsUsing PIEB compared to CEI as the background maintenance epidural analgesia method in conjunction with PCEA reduced the number of women requiring clinician rescue boluses while providing comparable labor analgesia. The findings of this clinical care impact study confirm the results of randomized controlled studies and suggest PIEB may be a preferable technique to CEI for the maintenance of labor analgesia.     

不同脉冲间隔时间程控硬膜外间歇脉冲注入模式对分娩镇痛效果的影响

目的 比较不同脉冲间隔时间下程控硬膜外间歇脉冲注入(PIEB)模式和持续恒速输注(CEI)模式用于分娩镇痛的临床效果。方法 选择单胎妊娠、头位、足月初产妇95例,年龄20～40岁,ASAⅡ或Ⅲ级,孕期37～41周,随机分为三组：传统CEI模式组(C组,n=31)、PIEB模式间隔时间60 min组(P60组,n=32)和PIEB模式间隔时间40 min组(P40组,n=32)。在宫口扩张至1～4 cm时,采用硬膜外阻滞行分娩镇痛,注射负荷量后15 min为产妇镇痛开始时间。C组于镇痛开始后立即开启CEI模式,持续以10 ml/h恒速输注。P60组于镇痛开始后60 min开启PIEB模式,单次脉冲10 ml,脉冲间隔时间60 min。P40组于镇痛开始后40 min开启PIEB模式,单次脉冲10 ml,脉冲间隔时间40 min。镇痛泵配方为0.075%罗哌卡因+0.5μg/ml舒芬太尼100 ml,单次按压量5 ml,锁定时间15 min。记录镇痛前(t₀)、镇痛后1 h(t₁)、镇痛后2 h(t₂)、宫口开全(t     

不同材质硬膜外导管用于程控硬膜外脉冲注射对分娩镇痛效果的影响

目的 观察不同材质硬膜外导管用于程控硬膜外脉冲注射(PIEB)对分娩镇痛效果及不良事件的影响.方法 选择拟行硬膜外分娩镇痛初产妇200例,年龄24～30岁,BMI<30 kg/m2,ASAⅠ或Ⅱ级.采用随机数字表法将产妇分为两组:钢丝加强型硬膜外导管组(S组)和普通塑料硬膜外导管组(N组),每组100例.两组均连接程控...     

全麻复合硬膜外麻醉及镇痛对开胸手术患者细胞免疫功能及红细胞糖代谢的影响

目的探讨硬膜外麻醉和镇痛对开胸手术患者术中及术后细胞免疫功能及红细胞糖代谢的影响。方法 40例行择期食管癌开胸手术患者,随机均分为静脉全麻复合胸段硬膜外阻滞及术后硬膜外镇痛组(A组)和全静脉麻醉及术后静脉镇痛组(B组)。分别与于麻醉前(T0)、切皮后2h(T1)、术后4h(T2)、24h(T3)、48h(T4)抽取两组患者的外周静脉血,测定血浆Th1细胞和Th2细胞的比值。同时测定红细胞内磷酸果糖激酶(PFK)、葡萄糖-6磷酸脱氢酶(G-6PD)、醛糖还原酶(AR)活性。结果 T3、T4时两组Th1、Th1/Th2明显低于T0时(P0.05),且A组明显高于B组(P0.05)。与T0时比较,T3、T4时两组PFK活性明显降低(P0.05),T3时B组G-6PD和AR活性明显升高,且明显高于A组(P0.05)。结论硬膜外麻醉及镇痛能抑制Th0细胞向Th2细胞的过度分化,保护机体细胞免疫功能并改善机体红细胞糖代谢。     

Postoperative analgesia with intravenous fentanyl PCA vs epidural block after thoracoscopic pectus excavatum repair in children

Background: The aim of this prospective, randomized trial was to compareanalgesia, sedation, and cardiorespiratory function in childrenafter thoracoscopic surgery for pectus excavatum repair, usingtwo types of analgesia—epidural block with bupivacaineplus fentanyl vs patient-controlled analgesia (PCA) with fentanyl. Methods: Twenty-eight patients scheduled for thoracoscopic pectus excavatumsurgery were randomly assigned to receive either thoracic epiduralblock or i.v. PCA for postoperative analgesia. Pain was assessedusing a visual-analogue scale (VAS). The Ramsay sedation score,arterial pressure, ventilatory frequency, and heart rate werealso measured, and blood gas analysis was performed regularlyduring the first 48 h after surgery. Results: A significant decrease in the VAS pain score, Ramsay sedationscore, heart rate ventilatory frequency, systolic and diastolicblood pressure, and Pa_CO2, and a significant increase in Pa_O2and oxygen saturation were found over time. Patients in thePCA group had significantly higher Pa_CO2 values. In addition,a significantly slower decline of systolic blood pressure andheart rate, and faster recovery of Pa_CO2 were found in PCA patientsthan in patients with epidural block. Conclusions: I.V. fentanyl PCA is as effective as thoracic epidural for postoperativeanalgesia in children after thoracoscopic pectus excavatum repair.Bearing in mind the possible complications of epidural catheterizationin children, the use of fentanyl PCA is recommended.