罗哌卡因经Spinocath导管行连续腰麻及PCA用于下腹部术的临床观察

目的观察罗哌卡因经Spinocath导管行连续腰麻(CSA)及术后自控镇痛(PCA)应用于下腹部手术的安全性和有效性。方法50例ASAⅠ-Ⅱ级拟行下腹部手术的患者,于L2～3间隙穿刺置入24GSpinocath连续腰麻导管,分次注入0.75%罗哌卡因2.5ml。术后PCA随机分为三组,A组(n=16):0.15%罗哌卡因;B组(n=16):0.125%罗哌卡因;C组(n=18):0.125%罗哌卡因 0.0002%芬太尼,容量均为60ml,三组背景输注速度1ml/h,PCA单次剂量0.5ml,时间锁定30min。观察术中HR、MAP、SpO2的变化,最高阻滞平面,运动阻滞程度(改良Bromage分级法),麻醉效果分级,PCA镇痛效果(视觉模拟评分法VAS)及不良反应和并发症。结果所有患者HR、MAP、SpO2均在正常范围内。最高阻滞平面为T7.2±0.9,改良Bromage评级均为Ⅲ级,麻醉效果满意率为96%。VAS评分A、C两组明显低于B组(P<0.01)。A组运动阻滞恢复时间较B、C两组明显延长(P<0.01)。结论下腹部手术中,采用罗哌卡因经Spinocath导管行连续腰麻及PCA,安全有效,具有可行性。     

罗哌卡因在产科手术中的应用体会

罗哌卡因是一种新型的长效酰胺类药物,它对中枢神经系统和心血管系统毒性低,具有感觉和运动分离特性。罗哌卡因蛛网膜下腔阻滞麻醉具有起效迅速,麻醉效果确切,失败率低,肌肉松弛满意,便于操作等优点,已广泛用于临床妇产科的麻醉。1资料与方法1.1一般资料选择ASAⅠ-Ⅱ级,体质量60~82kg的产科患者,健康、单胎、足月妊娠的初产妇90例。年龄21~30岁,无产科并发症及凝血功能障碍的麻醉禁忌证。无胎儿宫内窘迫、新生儿先天性疾病等。90例患者随机分为A、B、C 3组1.2方法3组病人入室后常规检测ECG、心率、血压、血氧饱和度,开放上肢静脉。手术开始前输入复方氯化钠500mL。取左侧卧位,常规消毒皮肤,选择L2-3为穿刺点,先行硬膜外穿刺,成功后经硬膜外穿刺针导入腰麻针,回抽见脑脊液流出后A组;注入0.75%罗哌卡因2mL。B组:注入0.75%布比卡因2mL。C组:注入0.375%罗哌卡因2mL,拔出腰麻针,迅速向头端置入硬膜外导管3.5 cm后改平卧。术中持续吸氧,酌情使用辅助药物,时间>2h时硬膜外追加2%利多卡因5~8mL。术中当SBP<90mmHg,静脉注射麻黄碱15~30mg,观察记录患者的生命体征,镇痛效果...     

O.75%罗比卡因与O.75%布比卡因腰麻-硬膜外联合麻醉应用于剖宫产手术的评价

目的比较0.75%罗哌卡因与0.75%布比卡因腰麻硬膜外联合麻醉用于剖宫产手术的可行性.方法ASA Ⅰ～Ⅱ级初产妇40例于腰硬联合麻醉下行剖宫产手术,随机、双盲分两组:R组(n=20)腰麻用药为0.75%罗哌卡因1.2～1.4ml(9～10.5mg);B组(n=20)腰麻用药为0.75%布比卡因,剂量同R组.术中两组麻醉效应不足时经硬膜外导管补充1.6%利多卡因.术中连续监测呼吸和循环状况,评估麻醉效应,并观察围术期不良反应的发生及新生儿情况.结果两组最高阻滞平面及达到时间相似(P＞0.05),但R组感觉和运动神经阻滞起效慢,维持时间短(P＜0.05);下肢运动阻滞程度R组显著低于B组(P＜0.01);术中R组有4例(20%)发生心动过缓,B组5例(25%)出现主观气促感;新生儿Apgar评分及脐动脉血气值在正常范围内,两组比较无差异(P＞0.05).结论0.75%罗哌卡因用于硬腰联合麻醉剖腹产手术安全有效,与0.75%布比卡因相比,下肢运动阻滞弱且恢复迅速.     

0.75%罗比卡因与0.75%布比卡因腰麻—硬膜外联合麻醉应用于剖宫产手术的评价

目的比较0.75%罗哌卡因与0.75%布比卡因腰麻硬膜外联合麻醉用于剖宫产手术的可行性.方法ASAⅠ～Ⅱ级初产妇40例于腰硬联合麻醉下行剖宫产手术,随机、双盲分两组R组(n=20)腰麻用药为0.75%罗哌卡因1.2～1.4ml(9～10.5mg);B组(n=20)腰麻用药为0.75%布比卡因,剂量同R组.术中两组麻醉效应不足时经硬膜外导管补充1.6%利多卡因.术中连续监测呼吸和循环状况,评估麻醉效应,并观察围术期不良反应的发生及新生儿情况.结果两组最高阻滞平面及达到时间相似(P＞0.05),但R组感觉和运动神经阻滞起效慢,维持时间短(P＜0.05);下肢运动阻滞程度R组显著低于B组(P＜0.01);术中R组有4例(20%)发生心动过缓,B组5例(25%)出现主观气促感;新生儿Apgar评分及脐动脉血气值在正常范围内,两组比较无差异(P＞0.05).结论0.75%罗哌卡因用于硬腰联合麻醉剖腹产手术安全有效,与0.75%布比卡因相比,下肢运动阻滞弱且恢复迅速.     

罗哌卡因复合舒芬太尼蛛网膜下腔麻醉在剖宫产术中的应用

目的探讨罗哌卡因复合小剂量舒芬太尼蛛网膜下腔注射在剖宫产术中的应用。方法将120例择期行剖宫产术产妇随机均分3组:A组为0.75%罗哌卡因10 mg。B组为0.75%罗哌卡因10 mg复合舒芬太尼3μg。C组为0.75%罗哌卡因10 mg复合舒芬太尼5μg。经L2-3行腰—硬联合麻醉,留置硬膜外导管备用。记录3组产妇麻醉效果,感觉和运动阻滞程度和时间,术中血流动力学变化和不良反应、新生儿apgar评分及硬膜外追加局麻药情况。结果 3组均安全完成手术,最高感觉阻滞平面、运动阻滞程度及恢复时间、新生儿apgar评分差异无统计学意义。麻醉优良率C组>B组>A组,但皮肤瘙痒的例数C组>B组>A组,C、B 2组镇痛时间长于A组(P<0.05),3组产妇生命体征变化差异无统计学意义,均无呼吸抑制发生。硬膜外追加局麻药的例数A组明显高于C、B 2组(P<0.05)。结论罗哌卡因复合舒芬太尼蛛网膜下腔麻醉效果满意,术后镇痛时间长,不良反应少,可安全用于剖宫产术。     

Spinocath导管罗哌卡因连续腰麻用于关节置换手术和术后镇痛的探讨

目的：观察Spinocath导管罗哌卡因连续腰麻施行关节置换手术的麻醉与术后镇痛的有效性和安全性。方法：选择30例关节置换手术病人，经L2-3或L3-4棘间隙穿刺蛛网膜下腔并置入Spinocath导管，注入重比重罗哌卡因20mg以施行持续腰麻，监测血压、心率、阻滞平面、运动阻滞情况、持续时间及副作用。术后应用0.2%罗哌卡因持续输注泵镇痛，0.5-1ml/h，PCA1ml/次，镇定间隔时间30min，观察切口镇痛效果与副作用。结果：蛛网膜下腔注药后5min出现阻滞平面，20-30min阻滞平面固定，90min阻滞平面开始下降，维持时间120-150min，血压心率平稳，感觉与运动分离阻滞明显，术后镇痛各时间点VRS完全镇痛和较好镇痛率达68%-94%，VAS0-30比率为81%-88%。结论：Spinocath连续腰麻期间血流动力学相对稳定，可控性强，镇痛质量好，与硬膜外麻醉或单次腰麻相比具有更多的优点，似更适用于年老体弱病人。     

罗哌卡因连续腰麻用于关节置换术麻醉和术后镇痛的可行性

随着新的穿刺针与导管的问世，连续腰麻(CSA)的应用逐渐增多。本组应用Spinocath导管(B．Braun公司，德国)行CSA，选择罗哌卡因作为腰麻用药，进行关节置换手术麻醉及术后镇痛，观察其有效性和安全性。     

舒芬太尼复合罗哌卡因硬膜外麻醉在剖宫产术中的应用

目的 探讨小剂量舒芬太尼复合罗哌卡因硬膜外麻醉用于剖宫产术的临床效能及安全性.方法 选择60例ASA Ⅰ或Ⅱ级的剖宫产产妇.随机均分为两组.A组给予0.75%罗哌卡因12 ml 加舒芬太尼20 μg(1 m1),B组给予0.75%罗哌卡因12 ml加生理盐水1 ml.术中连续监测呼吸和循环状况,评估麻醉效能,观察围手术期不良反应的发生和新生儿情况.结果 A组的感觉阻滞起效时间、平面达T10的时间及达到最高阻滞平面时间均明显短于B组(P＜0.01);A组最高阻滞平面明显高于B组(P＜0.01);两组不良反应、Apgar评分差异无统计学意义.结论 剖宫产手术产妇硬膜外罗哌卡因麻醉复合小剂量舒芬太尼的麻醉效果优于单纯应用罗哌卡因.对新生儿Apgar评分无明显影响.     

剖宫产手术中罗哌卡因复合小剂量芬太尼对硬膜外麻醉效果的影响

目的探讨不同剂量的芬太尼复合罗哌卡因硬膜外麻醉效果与安全性,为临床应用提供参考。方法行择期剖宫产手术的产妇随机分为3组。A组:硬膜外单纯给予0.75%罗哌卡因;B组:硬膜外给予0.75%罗哌卡因+0.01mg芬太尼,C组:硬膜外给予0.75%罗哌卡因+0.02mg芬太尼。监测产妇血流动力学,测定感觉与运动神经阻滞起效时间,切皮及胎儿取出时产妇疼痛程度(VAS评分),产妇术后24小时内术后恶心呕吐(PONV)、瘙痒、寒战发生率,新生儿出生后APGAR评分。结果 A组追加罗哌卡因产妇数量大于C组(P0.05),A组与B组差异无统计学意义。A组感觉神经阻滞起效时间长于B、C组(P0.05),而B组与C组之间差异无统计学意义;A组胎儿取出时VAS评分高于C组(P0.05),A组与B组差异不具有统计学意义。各组产妇围术期不良反应发生率及各组新生儿出生后APGAR评分差异无统计学意义。结论硬膜外腔给予0.75%罗哌卡因+0.02mg芬太尼,可以缩短剖宫产术前等待时间,提高产妇术中舒适度,且安全性良好,可以在临床推广。     

罗哌卡因和布比卡因用于老龄患者下肢手术麻醉中的对比研究

【摘要】 目的 探讨在老龄患者下肢手术的麻醉中等效剂量罗哌卡因和布比卡因麻醉效果以及对手术的影响。方法 选择拟行股骨颈骨折手术老龄患者50例,随机分为罗哌卡因组(R组)和布比卡因组(B组)。两组均采用腰硬联合麻醉(CSEA),分别给予0.5%罗哌卡因2.5 mL和0.5%布比卡因2.5 mL注入蛛网膜下腔。术中麻醉效应不足时硬膜外给予2%利多卡因。术中监测呼吸循环状况,评估麻醉效果,并观察不良反应。结果 两组麻醉效果,最高阻滞平面及不良反应的差异无统计学意义(P>0.05),B组的血压下降更加明显(P<0.05),R组下肢感觉阻滞起效更慢,持续时间更短(P<0.05),下肢运动阻滞程度显著低于B组(P<0.05)。结论 罗哌卡因和布比卡因在老龄患者下肢手术的腰硬联合麻醉都有效,罗哌卡因对循环系统影响更小,运动神经阻滞更轻且恢复迅速,更适合老龄患者下肢手术麻醉中的应用。     

Combined general and epidural anesthesia with ropivacaine for renal transplantation

AIM: To evaluate the effectiveness and safety of epidural ropivacaine anesthesia in association with light general anesthesia during renal transplantation and compare epidural and endovenous analgesia techniques for postoperative pain control. METHODS: Experimental design: prospective randomized study. SETTING: Organ Transplantation Center, Department of Surgery, "Tor Vergata" University of Rome, St. Eugenio Hospital, Rome. PATIENTS: 25 patients affected by chronic renal failure were enrolled in this study. Thirteen constituted the combined epidural-general anesthesia group (EPI-GEN), mean age 40.15+/-9.81 years; while the others constituted the general anesthesia group (GEN), mean age 46.75+/-7.45 years. Operation: cadaveric renal transplantation. Group EPI-GEN: epidural anesthesia performed with 12-15 ml of a ropivacaine 0.75% and fentanyl 5 microg/ml solution followed by light intravenous or inhalatory general anesthesia and postoperative epidural analgesia with ropivacaine 0.2% and fentanyl 2 mg/ml. Group GEN: inhalatory or intravenous general anesthesia and intravenous tramadol postoperative analgesia. Measurements: hemo-dynamics, renal function, arterial blood gases analysis, acid-base balance and postoperative pain data was collected and examined. RESULTS: Postoperative epidural analgesia resulted significantly more effective than intravenous tramadol. PaO(2)/FiO(2) ratio was significantly higher in group EPI-GEN patients both on awakening and throughout postoperative observation. Hemodynamics and renal function did not appear to differ significantly. CONCLUSION: Combined epidural-general anesthesia is as valid a technique as any for renal transplantation; however postoperative epidural ropivacaine analgesia resulted more effective than intravenous tramadol. Respiratory function appeared less affected, facilitating a fast and uncomplicated postoperative recovery.     

轻比重罗哌卡因在高龄患者腰-硬联合麻醉髋关节手术的应用

目的 观察高龄患者髋关节手术小剂量罗哌卡因腰-硬联合麻醉的麻醉效果及对循环呼吸功能的影响.方法 ASA Ⅱ或Ⅲ级髋关节手术60例,男18例,女42例,年龄(85.5±10.5)岁,体重(65.35±13.91)kg,随机分为两组,各组30例.A组腰麻用轻比重0.2%罗哌卡因5～7 mg,硬膜外阻滞用0.2%罗哌卡因;B组腰麻用重比重0.5%布比卡因8～10 mg,硬膜外阻滞用0.375%布比卡因硬膜外阻滞.记录两组麻醉效果和术中BP、HR、SpO2变化.结果 A组麻醉平面T8～T10,单侧,术中各时点BP、HR、SpO2平稳,Bromage评分患肢1～2分,健肢0～1分;B组麻醉平面T6～T8,双侧,术中各时点BP明显下降,HR明显减慢(P<0.01),也低于A组(P<0.05),Bromage评分双下肢以3～4分为主.结论 轻比重罗哌卡因腰-硬联合麻醉更适用于高龄髋关节手术患者.     

氯普鲁卡因、布比卡因和罗哌卡因在下肢手术腰-硬联合麻醉中的比较

目的比较氯普鲁卡因、布比卡因和罗哌卡因在下肢手术腰-硬联合麻醉(CSEA)中的应用效果。方法择期行髋关节及以下部位手术患者300例,随机均分成三组:氯普鲁卡因组(C组)、布比卡因组(B组)和罗哌卡因组(R组),蛛网膜下腔分别给予1.5%氯普鲁卡因、0.5%布比卡因和0.5%罗哌卡因各2 ml。记录患者感觉阻滞起效时间、平面固定时间、阻滞平面、腰麻持续时间和运动阻滞效果。结果 C组阻滞平面固定时间、腰麻持续时间明显短于B、R组(P<0.05)。C组感觉阻滞起效时间短于B组,但长于R组(P<0.05)。C组最高阻滞平面明显高于B、R组(P<0.05)。结论与0.5%罗哌卡因和0.5%布比卡因比较,1.5%氯普鲁卡因具有起效快、阻滞完善和运动阻滞效果弱的特点,小剂量氯普鲁卡因可用于手术时间较短的CSEA中的脊麻。     

连续腰麻对老年患者围术期血液流变学的影响

目的探讨连续腰麻（CSA）对老年患者围术期血液流变学状态的影响。方法择期行下腹部或下肢手术的老年患者40例，ASAⅠ～Ⅲ级，随机分为连续腰麻组（CSA组）和连续硬膜外阻滞组（CEA组，对照组），每组20例。CSA组常规行连续腰麻穿刺置管，给予0．375％布比卡因重比重液，CEA组常规行连续硬膜外穿刺置管，给予试验量2％利多卡因3ml和追加0．75％罗哌卡因8～10ml，两组患者麻醉平面均控制在胸10以下。分别于麻醉前（T0）、麻醉后1h（T1）、术毕（T2）、术后24h（T3）、术后48h（T4）各时间点采血行血液流变学检测。结果CSA组血浆黏度T2-T3降低（与T0比较，P〈0．05或0．01），全血低切黏度T3-T4低于T0（P均〈0．01）、全血中切黏度T2-T4均低于T0（P〈0．05或0．01），全血高切黏度T3-T4低于T0（P〈0．05或0．01）；CEA组血浆黏度T1-T3降低（与T0比较，P〈0．05或0．01），全血低切黏度T2-T3低于T0（P〈0．05或0．01）、全血中切黏度仅T3低于T0（P〈0．01），全血高切黏度T3-T4低于T0（P〈0．05）；上述各指标各时点组间比较差异无统计学意义。结论连续腰麻同样可以改善老年患者血液流变学状态。     

Excision of spinal tumor in a patient with severe pulmonary dysfunction using combined spinal and epidural anesthesia with two epidural catheters.

BACKGROUND AND OBJECTIVES: Combined spinal and epidural anesthesia (CSEA) has become common practice. We performed CSEA using two epidural catheters in a 69-year-old female with severe pulmonary dysfunction caused by a diaphragmatic hernia, who underwent surgical excision of a lumbar spinal tumor. METHODS: Combined spinal and epidural anesthesia was performed using two epidural catheters to minimize postoperative pulmonary complications. One epidural catheter was inserted above the surgical region, at the T11-12 interspace, and another one below the surgical region, via the sacral hiatus. Spinal anesthesia was produced using the L5-S1 interspace and 3 mL 0.5% bupivacaine. Oxygen, 3 L/min, was administered through a face mask during surgery. RESULTS: Fifteen minutes after spinal anesthesia, analgesic level was confirmed below T7 using the pinprick method. The patient complained of pain in the surgical region 10 minutes after the dura mater was opened. We injected 5 mL 2% mepivacaine through the upper epidural catheter to relieve the pain. We also injected 10 mL 2% mepivacaine through the lower catheter when she felt pain in the right leg. The perioperative course was uneventful. Oxygen saturation was maintained above 95%. CONCLUSIONS: Combined spinal and epidural anesthesia using two epidural catheters was used successfully to excise a spinal tumor in a patient with severe pulmonary dysfunction.     

Combined spinal and epidural anesthesia for cesarean section: a retrospective study with 0.5% hyperbaric bupivacaine

BACKGROUND: We investigated retrospectively the relationship between the intrathecal dose of 0.5% hyperbaric bupivacaine and the use of 2% mepivacaine through an epidural catheter. METHODS: Forty-nine patients undergoing cesarean section with combined spinal and epidural anesthesia (CSEA) were analyzed. They were divided into two groups; with (CSEA group) and without additional epidural injection group (spinal group). RESULTS: In the CSEA group (24 patients received 1.2 +/- 0.4 ml of 0.5% hyperbaric bupivacaine), 5-10 ml of 2% mepivacaine were required to achieve the adequate surgical anesthesia. In the spinal group (25 patients received 1.6 +/- 0.3 ml of 0.5% hyperbaric bupivacaine), cesarean section was performed without additional mepivacaine before delivery. The analgesic level and the amount of fluid infusion were similar in the two groups. However, 20% of patients in the spinal group showed hypotension (systolic blood pressure below 80 mmHg), although no patients in the CSEA group developed hypotension. The amount of ephedrine used before delivery was significantly larger in the spinal group (8.9 +/- 7.7 mg) than in the CSEA group (3.9 +/- 4.3 mg). CONCLUSIONS: Spinal anesthesia induced by 1.2 ml of 0.5% hyperbaric bupivacaine with sequential epidural block induced by 5-10 ml of 2% mepivacaine caused no hypotension during cesarean section.     

去甲肾上腺素预防腰硬联合麻醉下剖宫产低血压对母婴的影响

目的研究去甲肾上腺素预防腰硬联合麻醉下剖宫产低血压对母婴的影响。方法采用前瞻性研究方法,选择腰硬联合麻醉下择期行剖宫产的患者60例,按区组分A、B、C三组,每组20例。在麻醉开始前20 min分别按照以下速度恒速泵入药品,A组去甲肾上腺素0.05μg/kg·min,B组去甲肾上腺素0.1μg/kg·min,C组生理盐水0.1μg/kg·min,均持续20分钟停止。三组患者均在L_(3-4)间隙注入0.5%罗哌卡因3 mL行腰麻。观察记录三组患者以下时间点的平均动脉压(MAP)及心率(HR)变化,麻醉前(T_1)、腰麻给药(T_2)、给药后5 min(T_3)、给药后10 min(T_4)、给药后20 min(T_5)和术毕(T_6)术后8 h(T_7)和术后24 h(T_8),观察三组新生儿Apgar评分、血气分析、产妇不良反应发生情况。结果三组患者T_1时MAP及HR差异无统计学意义,A、B两组患者在各时间点MAP及HR差异无统计学意义(P0.05)。与T_1时比较,C组患者T_3、T_4、T_5时MAP明显降低,T_4时HR明显降低,差异有统计学意义(P0.05)。T_3、T_4、T_5时C组患者MAP明显低于A组和B组,差异有统计学意义(P0.05)。三组胎儿脐血PaO_2、PaCO_2、PH水平对比均不明显,差异均无统计学意义(P0.05)。A、B组患者恶心、呕吐、头痛发生率均显著低于C组,差异均有统计学意义(P0.05)。三组新生儿1 min、5 min的Apgar评分比较不明显,差异均无统计学意义(P0.05)。结论麻醉前去甲肾上腺素0.05μg/kg·min可有效预防腰硬联合麻醉下剖宫产低血压,且对母婴的影响较小,安全性较佳。     

Neurological deficit following lumbar epidural anesthesia with ropivacaine

A 38-year-old woman with placenta previa was scheduled for cesarean section. She had no abnormal medical history including neurological deficit before the operation. Prior to general anesthesia, an epidural catheter was inserted in the L2-3 interspace for postoperative analgesia. There was no difficulty in threading the catheter. No pain, paresthesia or bleeding was elicited at any time. After a test dose of 1% lidocaine 1 ml, a bolus of 0.75% ropivacaine 12 ml was injected through the epidural catheter. At the end of the operation, a continuous epidural infusion of 0.2% ropivacaine (the pump speed of 6 ml x h(-1)) was started. On the second postoperative day, sudden sensory loss level to L2 (right lower extremity), L3 (left one) and flaccid paralysis of bilateral lower extremities occurred. MRI and myelogram showed no abnormality of the spinal cord. Her neurological deficit showed slight improvement but her sensory and motor paralysis still remained. Neurotoxicity of ropivacaine may be the cause of this neurological deficit.     

Patient-controlled epidural analgesia with fentanyl-bupivacaine: influence of prior dural puncture

BACKGROUND AND OBJECTIVES: Combined spinal epidural anesthesia (CSEA) involves the epidural administration of local anesthetic and opioid solutions adjacent to the prior dural puncture, potentially increasing their diffusion into the subarachnoid space. This study was designed to evaluate the influence of dural puncture on the adequacy and extent of analgesia, and drugs requirements of patient-controlled epidural analgesia (PCEA) in the postoperative period. METHODS: In this prospective double-blind study, 40 patients undergoing major abdominal surgery under general anesthesia followed with PCEA were randomly assigned to either group I (preoperative insertion of an epidural catheter) or group II (preoperative dural puncture with a 25-g Quincke needle + insertion of an epidural catheter). Postoperatively, a PCEA pump delivered an infusion of 0.1% bupivacaine + fentanyl (3 microg/mL) at 5 mL/h. Participants were allowed to self-administer 5-mL boluses of the same solution with a 15-minute lock-out interval. Hourly epidural solution requirements were recorded for 40 hours. Sensory and motor block, and pain scores were also analyzed. RESULTS: There was no difference between groups with regard to epidural solution requirements, pain scores, spread of sensory blockade, or intensity of motor block. CONCLUSION: Dural puncture with a 25-gauge Quincke needle, performed as part of CSEA, does not influence the drug requirements when a combination of 0.1% bupivacaine and fentanyl (3 microg/mL) is used for PCEA after major abdominal surgery.