Comparison of hyperbaric and plain ropivacaine 15 mg in spinal anaesthesia for lower limb surgery

Background. Previously, plain ropivacaine 15 mg given intrathecallyhas been shown to be feasible for ambulatory surgery of lower-extremities.Hypothetically, hyperbaric solution could improve and shortenthe block. Methods. This prospective, randomized, double-blind study included56 patients undergoing surgery of lower extremities. They receivedintrathecally either 1.5 ml of ropivacaine 10 mg ml^–1and 0.5 ml of glucose 300 mg ml^–1 (HYP) or 2 ml of ropivacaine7.5 mg ml^–1 (PL). Results. All patients in Group HYP achieved T₁₀ dermatome analgesiabut only 64% (18/28) of Group PL. T₁₀ analgesia was reachedin 5 min (median, range 5–20 min) in the HYP group vs10 min (5–45 min) in the PL group (P=0.022), and fullmotor block in 10 min (5–45 min) vs 20 min (5–60min) (P=0.003), respectively. Group HYP had a longer durationof analgesia at T₁₀; 83 min (5–145 min) vs 33 min (0–140min) (P=0.004). Duration of sensory block from injection ofthe anesthetic to complete recovery was shorter in Group HYPthan in Group PL, 210 min (120–270 min) vs 270 min (210–360min) (P<0.001), as was duration of motor block, 120 min (5–150min) vs 210 min (120–330 min) (P<0.001). Patients ofGroup HYP attained discharge criteria earlier than those ofGroup PL (P=0.009). Conclusion. In comparison with the plain solution, 15 mg ofintrathecal hyperbaric ropivacaine produced a faster onset,greater success rate of analgesia at the level of T₁₀ dermatome,and faster recovery of the block.     

Comparison of plain and hyperbaric solutions of ropivacaine for spinal anaesthesia

Background. Preliminary work has shown that ropivacaine providesspinal anaesthesia of shorter duration than bupivacaine, andmay be of particular use in the day-case setting. However, thereare few data comparing the actions of plain and hyperbaric solutionsof this drug. Methods. Forty ASA grade I–II patients undergoing electiveperineal surgery under spinal anaesthesia were randomized toreceive 3 ml ropivacaine 5 mg ml^–1, either in plain solutionor with glucose 50 mg ml^–1. The extent and duration ofsensory and motor block, pulse rate, blood pressure, and timeto mobilization were recorded. Results. Two patients (one per group) were withdrawn becauseof total block failure. There were significant differences inmedian time to onset of sensory block at T10 (plain 10 min;hyperbaric 5 min; P<0.01), median maximum extent (plain T8;hyperbaric T4; P<0.05), and median duration of sensory blockat T10 (plain 25 min; hyperbaric 115 min; P<0.001). However,median times to complete regression of both sensory (270 vs240 min; P<0.05) and motor (180 vs 120 min; P<0.001) blockwere longer in the plain group. Patients therefore mobilizedsooner in the hyperbaric group (218 [n=16] vs 286 min [n=17];P<0.01). All the hyperbaric blocks were adequate for surgery,but three patients receiving plain ropivacaine required generalanaesthesia. Conclusion. Addition of glucose 50 mg ml^–1 to ropivacaine5 mg ml^–1 increases the speed of onset, block reliability,duration of useful block for perineal surgery, and speed ofrecovery. Plain solutions are less reliable for surgery abovea dermatomal level of L1.      

Minimum effective anaesthetic concentration of hyperbaric lidocaine for spinal anaesthesia

Purpose

Minimum effective anaesthetic concentration (MEAC) of lidocaine for spinal anaesthesia, defined as the concentration at which a spinal anaesthetic agent produces surgical anaesthesia within 20 min of administration in 50% of patients, was determined in a randomised, double-blind study in young patients undergoing knee and ankle surgery.

Methods

Using the combined spinal-epidural technique, 48 or 72 mg hyperbaric lidocaine containing dextrose 7.5% was administered intrathecally to 43 patients at concentrations ranging from 0.2–0.9%. The choice of lidocaine concentration was determined by Dixon’s up-and-down method, Complete anaesthesia was defined as: ( I ) pinprick anaesthesia at or higher than T₁₂, (2) anaesthesia to transcutaneous tetanic electric stimulation (50 Hz at 60 mA for five seconds) in the knees and (3) complete leg paralysis; all occurring in both lower extremities within 20 min. Epidural anaesthesia was initiated if anaesthesia was incomplete.

Results

In the 48 mg group, MEAC was 0.54% (95% Cl-0.21–0.87). Anaesthetic effect was variable with mean duration of anaesthesia of 29 min (range: 20–50 min) and maximum pinprick sensory level ranging from T₂-T₁₀. In the 72 mg group, successful anaesthesia was achieved consistently at a concentration of 0,3%, i.e., MEAC was < 0.3%. Mean duration of complete anaesthesia was 46 min (range: 30–60 min) with maximum sensory level from T₃–T₈.

Discussion

Spinal anaesthesia can be accomplished with very dilute lidocaine solutions (< 0.9%). The value of MEAC is dose-dependent, i.e., complete anaesthesia can be accomplished with lower concentrations by increasing the dose of spinal anaesthetic administered.     

A comparison of glucose-free 2% lidocaine and hyperbaric 5% lidocaine for spinal anaesthesia

Fifty patients scheduled to undergo transurethral surgery of the bladder were allocated to receive spinal anaesthesia with either glucose-free 2% lidocaine (80 mg) or hyperbaric 5% lidocaine (80 mg). Onset time, cephalad spread of analgesia, duration of analgesia, duration and intensity of motor block, quality of analgesia, and the patients' ability to walk 5 m and to micturate postoperatively were assessed. Onset and spread of analgesia were fast and comparable in the two groups. At 60 min, the median segmental level of analgesia was T9 and T10 for the 2% and the 5% group, respectively, allowing transurethral surgery to be performed for at least 1 h. In the 2% group the motor block was more pronounced and longer lasting than in the 5% group. Two patients in the 5% group needed general anaesthesia because of pain. The time from injection of the spinal anaesthetic until the patients were able to walk 5 m and to micturate was equal in the two groups, and 89% of all the patients were able to walk and micturate within 4 h. It is concluded that spinal anaesthesia with 80 mg and 2% or 5% lidocaine provides analgesia for transurethral surgery and is characterized by fast recovery of motor and detrusor function.     

Transient neurological symptoms after spinal anaesthesia with hyperbaric 5% lidocaine or general anaesthesia

Transient neurotoxicity of concentrated local anaesthetics has been thought to be the main reason for transient neurological symptoms after spinal anaesthesia. Profound musculoligamental relaxation by high doses of local anaesthetics may contribute to the development of postoperative musculoskeletal pain. In order to evaluate the role of the loss of strength of the supportive structures of the spine in the development of transient neurological symptoms, 60 patients (ASA I-II) undergoing minor orthopaedic, varicose vein or inguinal hernia operations were allocated randomly to receive spinal anaesthesia with hyperbaric lidocaine 50 mg ml-1 (85-100 mg) or balanced general anaesthesia with neuromuscular block. Patients were interviewed 24 h later and after 1 week they returned a written questionnaire. Transient neurological symptoms, consisting of pain in the buttocks or pain radiating symmetrically to the lower extremities, occurred in eight patients (27%) receiving spinal anaesthesia and in one patient (3%) receiving general anaesthesia (P < 0.05). We conclude that a transient neurotoxic effect of hyperbaric lidocaine 50 mg ml-1 is probably the main reason for transient neurological symptoms after spinal anaesthesia but musculoligamental relaxation may contribute to the development of low back or leg pain after both anaesthetic techniques.      

重比重罗哌卡因用于老年蛛网膜下腔麻醉

目的研究重比重罗哌卡因用于老年患者蛛网膜下腔阻滞的安全性和有效性。方法择期肛门会阴部手术老年患者120例,ASA Ⅰ或Ⅱ级。随机分为三组,每组40例。于 L_(3～4)间隙穿刺。注药时患者取坐位,以0.2 ml/s 的速度分别注入重比重混合局麻药。用针刺法测感觉阻滞平面.用改良 Bromage 法评估下肢运动神经阻滞程度.以患者提肛收缩肛门和指诊观察肛门括约肌阻滞程度。比较三组患者在感觉、运动阻滞及恢复上的异同,记录血压、心率变化及不良反应。结果三组均能达到感觉阻滞。但 R_1组肛门括约肌阻滞不完善者多于 R_2、R_3组(P<0.01);R_2组下肢运动神经阻滞起效时间长于 R_3组(P<0.01);运动阻滞恢复时间短于 R_2组(P<0.01);R_2组感觉阻滞消退到 S_(1～2)时间、完全下肢运动神经阻滞发生率及尿潴留发生率明显少于 R_3组(P<0.01)。结论罗哌卡因重比重液6 mg 于老年患者应用蛛网膜下腔麻醉安全有效.并发症少。     

Selective sensory spinal anaesthesia with hypobaric lidocaine for anorectal surgery

Background: Lidocaine has been used for spinal anaesthesia since 1948, seemingly without causing concern until recently. This study aimed at evaluating the feasibility of performing anorectal surgery in outpatient settings with low hypobaric lidocaine doses. Methods: Three groups of 50 patients, physical status ASA I–II, undergoing anorectal surgical procedures in a prone jack‐knife position, received 3 ml (18 mg), 4 ml (24 mg) or 5 ml (30 mg) of hypobaric 0.6% lidocaine. Sensory and motor blockade, time until first urination, ambulation, complications and the need for analgesics were evaluated. Patients were followed until the third post‐operative day. Results: Adequate sensory block was obtained in all patients. Blockade was significantly lower in Group 1. The level at 15 min was L₁ with 3 ml, T₁₁ with 4 ml and T₁₀ with 5 ml. Only 24 patients presented a moderate motor block. There was no hypotension, nausea or vomiting, urine retention, transitory neurological symptom or post‐dural puncture headache in any patients. There was one case of bradycardia with 4 ml and two cases with 5 ml. Conclusions: Hypobaric lidocaine predominantly provided a sensory block after injection in the prone jack‐knife position. The smallest dose (3 ml=18 mg) provides sufficient analgesia with a lesser dispersion and a shorter duration. The major advantages were haemodynamic stability and a high degree of patient satisfaction.     

Repeated transient neurological symptoms after spinal anaesthesia with hyperbaric 5% lidocaine

We report a case of repeated delayed pain after cystoscopy under spinal lidocaine anaesthesia, which may be caused by transient radicular irritation. The possible aetiology of the symptoms is discussed.      

定容小剂量利多卡因和罗哌卡因蛛网膜下腔麻醉在输尿管镜技术日间手术中的应用研究

目的 探讨定容小剂量利多卡因和罗哌卡因蛛网膜下腔麻醉(腰麻)应用于输尿管镜技术日间手术的有效性和安全性. 方法 前瞻性纳入输尿管镜技术日间手术患者100例,按随机数字表法分为4组(每组25例):L1组,利多卡因10 mg;L2组,利多卡因15 mg;R1组,罗哌卡因10 mg;R2组,罗哌卡因15 mg.分别将所用麻醉药物稀释于脑脊液至3 ml,给药速度0.2 ml/s.记录麻醉前(T0)及麻醉给药后3 min(T1)、6 min(T2)、20 min(T3)、30 min(T4)、60 min(T5)时患者SBP、DBP、HR等指标变化,监测感觉阻滞起效时间、运动阻滞起效时间、麻醉质量和毒副作用,评估痛觉恢复时间、运动阻滞恢复时间和留院时间. 结果 麻醉后L1组、R1组循环稳定,L2组、R2组在30 min内BP和HR下降(P＜0.05).各组感觉阻滞起效时间差异无统计学意义(p＞0.05),L1组、L2组运动阻滞较R1组、R2组起效时间缓慢且效果轻微.Lovett评分L1组显著高于其他3组(P＜0.05),L1组的留院时间显著低于其他3组(P＜0.05),各组均未发现短暂性神经综合征(transient neurologicalsymptoms,TNS)等毒副作用. 结论 定容小剂量利多卡因腰麻方法循环稳定、感觉阻滞完善、运动阻滞弱、留院时间短、神经毒性极小,可以安全有效地应用于输尿管镜技术日间手术.     

Spinal anaesthesia for day case surgery

The quality of recovery favours spinal anaesthesia if the incidence of headache can be made sufficiently small. This can be done by excluding young adults who are most at risk. However, those anaesthetists who are prepared to become practised at using fine bore needles can offer day-case patients of all ages spinal blocks. It is suggested that nothing larger than 26-gauge needles are used for day-cases. Pencil and oval pointed needles also appear to confer advantages. Spinal anaesthesia is gaining momentum and need not be denied to day-case patients.     

Dose response study of lidocaine 1% for spinal anaesthesia for lower limb and perineal surgery

Purpose

To compare the sensory and motor block produced by three different volumes of intrathecal lidocaine 1% and thereby determine the appropriate volume to administer for surgery of the lower limbs and perineum.

Methods

Forty-eight patients scheduled for perineal or lower limb surgery were randomly assigned to receive 4, 6 or 8 ml lidocaine 1% intrathecally. The onset, spread, duration and regression of analgesia and motor block and side effects were evaluated (by a blinded observer whenever possible).

Results

The maximum cephalad spread in the 6 ml (T₈ ± 3) and 8 ml (T₄ ± 1.7) groups were higher than the 4 ml group (T₁₂ ± 2.2,P < 0.01). In the 4 ml group, six patients (33%) did not achieve analgesia to T₁₂ and four (22%) did not have complete motor blockade. Patients given 8 ml had longer duration of block (duration at T₁₂: 104 ± 23vs 60 ± 24, 67 ± 14 min,P < 0.01; 8 mlvs 4, 6 ml) and slower recovery times (sensory recovery: 188 ± 27vs 142 ± 27, 157 ± 28 min,P < 0.01; 8 mlvs 4, 6 ml). Two patients (18%) from the 8 ml group and one (5%) from the 6 ml group had transient hypotension.

Conclusion

Four millilitres intrathecal lidocaine 1% is adequate for perineal surgery but for lower limb procedures, 6 ml is more appropriate as it consistently provides sensory analgesia above L₁ dermatome and complete motor block. Eight ml gives an unnecessarily high block with higher incidence of hypotension.     

Low dose hyperbaric bupivacaine for unilateral spinal anaesthesia

Purpose

To evaluate the effects of hyperbaric bupivacaine concentration in producing unilateral spinal anaesthesia.

Methods

With Ethical Committee approval and written consent, 60 patients undergoing lower limb surgery were placed in the lateral position with the side to be operated on dependent. After durai puncture (25-gauge Whitacre spinal needle), the needle hole was turned toward the dependent side and patients were randomly assigned to receive 8 mg of either 0.5% (Group_05%, n = 30) or 1% (Group_1%, n = 30) hyperbaric bupivacaine. The lateral position was maintained for 15 min, while a blinded observer recorded loss of pinprick sensation and degree of motor block on both sides until two segment regression of sensory level on the dependent side.

Results

At the end of the 15 min lateral position spinal anaesthesia was more frequently unilateral in Group_0.5% (80%) than in Group_1%(53%)(P < 0.05). However, 30 min after patients were turned supine, unilateral spinal anaesthesia decreased to 60% of cases in Group_0.5% and 40% of cases in Group_1%(P = NS). The maximum sensory level on the dependent side [T₁₀(L₁ ? T₂) in Group_0.5% and T₈ (T₁₂ ? T₃) in Group_1%], time to reach it [20 (5–30) min in Group_0.5% and 25 (10–35) min in Group_1%], and time to two segment regression of sensory level [80 (30–135) min in Group_0.5% and 75 (20–135) min in Group_1%] were similar in both groups.

Conclusion

Highly concentrated solutions of hyperbaric bupivacaine are not advantageous in obtaining a unilateral spinal anaesthesia, when a small anaesthetic dose is injected slowly through a Whitacre spinal needle.     

Unilateral spinal anaesthesia with hyperbaric bupivacaine

Background: The dosage of local anaesthetic and the time the patient must be kept in the lateral decubitus position for a unilateral spinal anaesthesia is not known. The aim of this study was to determine the ideal dosage of hyperbaric bupivacaine and the time required for the lateral decubitus position for a unilateral spinal block. Methods: Ninety patients who were scheduled to receive spinal block for surgery in the lower extremity were randomised into 9 groups (n=10). The spinal block was performed through the L₄–L₅ intervertebral space with the patient in the lateral decubitus position. Patients in groups Ia, Ib, Ic; IIa, IIb, IIc; IIIa, IIIb, IIIc received 1.5 ml of 0.5%, 2 ml of 0.5%, and 2.5 ml of 0.5% hyperbaric bupivacaine solutions, respectively. The patients were turned to the supine position for 5 min after the injection in groups Ia, IIa, IIIa, 10 min after the injection in groups Ib, IIb, IIIb, and 15 min after the injection in groups Ic, IIc, IIIc. The onset and regression of sensory and motor block were checked and compared between the dependent and non-dependent sides in each group. Results: The rate of block progression of the non-dependent side was higher in the groups receiving 2.5 ml 0.5% hyperbaric bupivacaine solution than in the other groups; at the same time the level of block was higher and the duration of block was longer. The incidence of hypotension was 10–20% in these groups. In the 2 ml 0.5% hyperbaric bupivacaine solution groups, a satisfactory block level and duration of anaesthesia for surgery was obtained. The rate of block progression to non-dependent side in the groups receiving 1.5 ml of 0.5% hyperbaric bupivacaine solution was lower than the other groups, but the duration of block was shorter and the level of block was lower than the other groups. Conclusion: For unilateral spinal anaesthesia in lower extremity operations, 2ml 0.5% hyperbaric bupivacaine solution for operations above the knee and 1.5 ml 0.5% hyperbaric bupivacaine solution for operations below the knee and keeping the patients for 10 min in the lateral decubitus position were found to be appropriate.