Local anesthesia for abdominoplasty,liposuction, and combined operations

This article describes a procedure to perform abdominoplasty, liposuction, and combined operations under local anesthesia. With an anesthetic solution composed of 25 cc of 2% lidocaine, 25 cc of 0.5% bupivacaine, 1 cc of epinephrine or ornipresine, and 350 cc of saline solution, a satisfactory dilution with low concentration and lasting effects was obtained. After infiltration a large amount was lost in the incision, the dissection, and the resected dermofatty tissue. A small amount of anesthetic remained in the operated area to be metabolized by the liver. Low lidocaine levels were found in venous blood samples during surgery. This type of anesthesia is advised in minor, limited, and normal abdominoplasties in normalsized patients, or major abdominoplasties in small patients. In liposuction procedures, it is possible to anesthetize the patient using the same procedure and operate in an equivalent area. As a high proportion of the infiltrated anesthesia was lost during the operation, a similar amount could be used to infiltrate and operate other areas so that an abdominoplasty might be combined with liposuction or mastoplasty. We have experience with 25 abdominoplasties and 21 liposuctions performed under local anesthesia. There were no complications related to local anesthesia and no one had unpleasant memories of intraoperative events.This paper was awarded with a special mention in the Argentinian Congress on Plastic Surgery, Mendoza, Argentina, 1990     

不同局部麻醉药硬膜外阻滞麻醉行隆乳术的效果

目的观察隆乳手术中不同局部麻醉药混合液行硬膜外阻滞的麻醉效果及并发症.方法 120例行乳房假体置入术患者分为4组,以T4～T5棘突间隙为硬膜外穿刺点,分别注入含1 %利多卡因及0.375 %罗哌卡因、0.25 %罗哌卡因、0.25 %布比卡因的混合液及单纯1.3 %利多卡因溶液,初量13 ml,观察麻醉效果及对血流动力学的影响和并发症.结果切皮均无疼痛,脉搏氧饱和度无明显变化,血压及心率轻度降低.1 %利多卡因加0.375 %罗哌卡因、0.25 %罗哌卡因或0.25 %布比卡因混合液组的阻滞麻醉效果较好,单纯1.3 %利多卡因组效果较差.65例(54 %)患者出现鼻塞,39例(33 %)麻醉后发生心动过缓,无组间差异.结论高位硬膜外阻滞麻醉可安全、有效地应用于隆乳房手术麻醉,1 %利多卡因与0.25 %罗哌卡因或布比卡因混合液不仅阻滞麻醉效果较好,对生理功能影响也较小.     

布比卡因和利多卡因肿胀液在局麻吸脂术中的应用效果比较

目的:结合在局麻吸脂术使用布比卡因的经验探讨肿胀液中布比卡因的安全使用、组成及其有效性。方法:选择2013年6月-2019年2月135例不同部位进行局麻负压吸脂的患者为研究对象,肿胀液主要成分为布比卡因和利多卡因,评估应用含布比卡因和利多卡因肿胀液在吸脂术中的药物组成、用量、疗效和安全性。结果:局麻吸脂中含布比卡因结合利多卡因的肿胀液适合于吸脂量低于4800ml的患者,仅含布比卡因一种麻醉药物的肿胀液在吸脂量为3600ml,布比卡因总用量为252mg(文献值为150mg)时未显示毒性;含布比卡因肿胀液组镇痛效果好于利多卡因组,术中起效快,术后1~4d无痛苦、恢复快、愈合好、并发症少、住院时间缩短一半。结论:布比卡因及布比卡因结合利多卡因的肿胀液在局麻吸脂中具有镇痛效果好、手术安全等优点,为其进一步应用提供了宝贵经验。证明布比卡因、尤其是布比卡因结合利多卡因作为肿胀液的麻醉药物值得进一步推广。     

Washout of local anesthetic during arthroscopy

The recommended dose of lidocaine is often insufficient to obtain adequate local anesthesia when performing knee arthroscopy, particularly in bilateral procedures. A prospective study was conducted to identify the quantity of anesthetic washed out of the knee by irrigation solution. Fourteen patients had knee arthroscopy performed with local anesthetic, either for diagnosis or reparative surgery. Anesthesia was obtained using 20 ml of 0.5% lidocaine injected intraarticularly at the beginning of each procedure, augmented in four cases by an additional 20 ml of 0.5% lidocaine during the procedure. Each of three portals was also infiltrated with bupivacaine 0.25% with epinephrine. Analysis of the normal saline effluent from knee irrigation during the procedure revealed that washout of lidocaine was 50% by weight (range, 42-66%). This percentage did not vary with age, operative time, or quantity of irrigation. We conclude that: (a) safe local anesthesia can be obtained in the average patient with less than the maximum dose of lidocaine, and (b) because of the 50% washout, the safe dose of lidocaine can be increased substantially if needed.     

Effectiveness of isobaric 0.5% bupivacaine and 5% lidocaine in continuous subarachnoid anesthesia with microcatheters

OBJECTIVES: To study the clinical effect of two isobaric local anesthetics infused through microcatheters for continuous subarachnoid anesthesia. MATERIAL AND METHODS: Patients undergoing surgery under continuous subarachnoid anesthesia were enrolled prospectively over 12 months. Twenty-seven-gage catheters were inserted through 22 G Sprotte (Intralong) needles. The two isobaric anesthetics (0.5% bupivacaine and 5% lidocaine) were studied in two successive six-month periods. One milliliter of local anesthetic was administered, followed by incremental doses of 0.5 ml until the required anesthetic level was reached. Hemodynamic variables were recorded, as were levels of anesthetic and motor blockade and complications developing during the surgical and postoperative periods. RESULTS: Thirty-one patients were anesthetized with isobaric 0.5% bupivacaine and 40 with isobaric 5% lidocaine. A high blockade was observed in three patients in the bupivacaine group and in 15 in the bupivacaine group (p < 0.05). The highest anesthetic level reached was T4. Hypotension occurred in one patient in the bupivacaine group and in 10 in the lidocaine group (p < 0.05). Blockade was difficult to increase to the appropriate level in 11 lidocaine patients and in one bupivacaine patient, whereas blockade of distal roots was difficult in 13 bupivacaine patients and in 7 lidocaine patients (p < 0.005). The total doses infused were 11.0 +/- 3.0 mg of 0.5% bupivacaine and 95.6 +/- 24.6 mg of 5% lidocaine. CONCLUSIONS: Isobaric 0.5% bupivacaine provides a more predictable anesthetic blockade with greater hemodynamic stability and a lower rate of difficulty in raising the level of blockade than does 5% lidocaine when administered through microcatheters for continuous subarachnoid anesthesia.     

Concentration- and pH-dependent effects of local anesthetics on onset of epidural anesthesia

This study was undertaken to determine the effect of concentration of pH-adjusted local anesthetics on the onset time of anesthesia.Lidocaine (0.9% and 1.8%) and bupivacaine (0.25% and 0.5%) were used. In the 0.9 percent lidocaine and 0.25 percent bupivacaine groups, the onset time of analgesia was shortened by about 100 and 200 seconds, when pH was adjusted to 7.4 and 7.0, respectively (P 0.05 and P 0.01). In the 1.8 percent lidocaine and 0.5 percent bupivacaine groups, however, pH adjustment exerted no significant effect on the onset time.Alkalinization of low-concentration local anesthetics shortened the onset time, whereas that of high-concentration did not shorten.(Fukuda T, Sato S, Naito H: Concentration- and pH-dependent effects of local anesthetic on onset of epidural anesthesia. J Anesth 4: 327–330, 1990)     

Comparative analysis of tissue reactions to anesthetic solutions: histological analysis in subcutaneous tissue of rats

Postanesthetic pain is a relatively common complication after local anesthesia. This complication may be caused by the anesthetic technique or by the anesthetic solution used. Tissue reactions induced by the anesthetic solutions may be one of the factors resulting in pain after anesthesia. The objective of this study was to comparatively analyze tissue reactions induced by different anesthetic solutions in the subcutaneous tissue of rats. The following solutions were utilized: 2% lidocaine without vasoconstrictor; a 0.5% bupivacaine solution with 1:200,000 adrenaline; a 4% articaine solution and 2% mepivacaine, both with 1:100,000 adrenaline; and a 0.9% sodium chloride solution as a control. Sterilized absorbent paper cones packed inside polyethylene tubes were soaked in the solutions and implanted in the subcutaneous region. The sacrifice periods were 1, 2, 5, and 10 days after surgery. The specimens were prepared and stained with hematoxylin and eosin for histological analysis. The results showed that there is a difference in tissue irritability produced by the local anesthetic solutions. The results also showed that there is no relation between the concentration of the drug and the inflammatory intensity, that the mepivacaine and articaine solutions promoted less inflammatory reaction than the bupivacaine, and that the lidocaine solution produced the least intense inflammation.     

Anesthetic Efficacy of a Combination of 0.5 M Mannitol Plus 127.2 mg of Lidocaine With 50 μg Epinephrine in Inferior Alveolar Nerve Blocks: A Prospective Randomized,Single-Blind Study

The purpose of this prospective, randomized, single-blind study was to determine the anesthetic efficacy of 127.2 mg lidocaine with 50 μg epinephrine compared to 127.2 mg lidocaine with 50 μg epinephrine plus 0.5 M mannitol in inferior alveolar nerve (IAN) blocks. Forty subjects randomly received 2 IAN blocks consisting of a 3.18 mL formulation of 127.2 mg lidocaine with 50 μg epinephrine and a 5 mL formulation of 127.2 mg lidocaine with 50 μg epinephrine (3.18 mL) plus 0.5 M mannitol (1.82 mL) in 2 separate appointments spaced at least 1 week apart. Mandibular anterior and posterior teeth were blindly electric pulp tested at 4-minute cycles for 60 minutes postinjection. Pain of solution deposition and postoperative pain were also measured. No response from the subject to the maximum output (80 reading) of the pulp tester was used as the criterion for pulpal anesthesia. Total percent pulpal anesthesia was defined as the total of all the times of pulpal anesthesia (80 readings) over the 60 minutes. One hundred percent of the subjects had profound lip numbness with both inferior alveolar nerve blocks. The results demonstrated that a 5 mL formulation of 127.2 mg lidocaine with 50 μg epinephrine plus 0.5 M mannitol was significantly better than the 3.18 mL formulation of 127.2 mg lidocaine with 50 μg epinephrine for all teeth. Solution deposition pain and postoperative pain were not statistically different between the lidocaine/mannitol formulation and the lidocaine formulation without mannitol. We concluded that adding 0.5 M mannitol to a lidocaine with epinephrine formulation was significantly more effective in achieving a greater percentage of total pulpal anesthesia than a lidocaine formulation without mannitol.Key Words: Inferior alveolar nerve block, Lidocaine, Mannitol, EpinephrineThe inferior alveolar nerve (IAN) block is the most frequently used injection technique for achieving local anesthesia for mandibular restorative and surgical procedures. However, the IAN block does not always result in successful pulpal anesthesia.^1–6 Failure rates (never achieving 2 consecutive 80 readings with the electric pulp tester) of 10 to 39% have been reported.¹ A possible reason for failure is the perineurial barrier around the nerve may not allow complete diffusion of the anesthetic solution into the nerve trunk.A previous study by Wolf et al⁷ demonstrated that lidocaine in combination with mannitol significantly improved the success of the IAN block. The proposed mechanism is that mannitol opens the perineurial membrane to allow for enhanced penetrability for lipophilic compounds⁸ (such as lidocaine), and it may also directly affect nerve conduction.⁹While Wolf et al⁷ demonstrated that 2.84 mL of 36 mg lidocaine with 18 μg epinephrine (1.80 mL) plus 0.5 M mannitol (1.04 mL) was significantly better than 1.8 mL of 36 mg lidocaine with 18 μg epinephrine for the IAN block in the molars and premolars, a 5 mL formulation of 63.6 mg lidocaine with 32 μg epinephrine (3.18 mL) plus 0.5 M mannitol (1.82 mL) was significantly better than 2.84 mL of lidocaine with epinephrine plus 0.5 M mannitol for all teeth except the central incisor. Therefore, increasing the amount of lidocaine plus mannitol increased success.Rood¹⁰ and Eldridge and Rood¹¹ have shown that a 5% lidocaine solution with 1 : 80,000 epinephrine increased the success rate of an IAN block when compared to a 2% lidocaine solution with 1 : 80,000 epinephrine. Rood and Sowray¹² also described a series of cases where 5% lidocaine provided adequate pain control when 2% lidocaine was inadequate. Lastly, Sandy and Rood¹³ discussed the use of 5% lidocaine in children. They showed a 5% lidocaine solution was helpful in achieving anesthesia when 2% lidocaine was inadequate.Because total pulpal anesthesia was not obtained by Wolf et al,⁷ further increasing the amount of lidocaine when combined with 0.5 M mannitol could potentially allow the anesthetic solution to permeate the nerve trunk in greater amounts, thereby increasing anesthetic efficacy. The purpose of this prospective, randomized, single-blind study was to determine the anesthetic efficacy of 127.2 mg lidocaine with 50 μg epinephrine compared to 127.2 mg lidocaine with 50 μg epinephrine plus 0.5 M mannitol in IAN blocks. Pain of injection and postinjection pain were also studied.     

Penile block via the subpubic space in 100 children

A technique for blocking the dorsal nerves of the penis was designed after reevaluation of the gross anatomy of the subpubic space and penis in children. The technique consists of inserting a short bevel needle in the two compartments of the subpubic space, where the nerves run before entering the base of the penis, and of injecting a small volume (0.1 mL/kg of body weight) of local anesthetic. This two-puncture procedure was prospectively evaluated in 100 children undergoing surgery of the penis under light general anesthesia. The local anesthetic was a solution of 1% lidocaine (Group A) or 0.5% bupivacaine (Group B). The technique did not require any special skill and was successful in all patients. In four cases, the block needle was withdrawn and reinserted due to venous blood reflux. No complications occurred and anesthesia was satisfactory for completion of surgery. The duration of postoperative pain relief was significantly longer in patients given bupivacaine than in those given lidocaine. It is concluded that the subpubic approach to the dorsal nerves of the penis is easy, safe, and reliable, and that 0.5% plain bupivacaine provides long-lasting postoperative pain relief.     

Comparison of lidocaine with and without bupivacaine for local dental anesthesia.

The purpose of this study was to investigate the effectiveness of a combination of bupivacaine and lidocaine and that of lidocaine alone for local dental anesthesia. First, on different days, healthy volunteers were given 2% lidocaine with 1/80,000 epinephrine or 2% lidocaine with 1/80,000 epinephrine + 0.5% bupivacaine, after which pain was produced with a pulp tester. No difference was found in the time until onset of anesthetic effect between the preparations. However, the duration of anesthetic effect was longer with both lidocaine and bupivacaine than with lidocaine alone. Next, patients undergoing dental surgery were given one of the anesthetic preparations, after which serum concentrations of the anesthetics and epinephrine were measured. The maximal serum concentration of lidocaine was higher and was reached sooner after injection in patients receiving lidocaine alone (1.74 microgram/ml after 5 min) than in patients receiving both anesthetics (0.85 microgram/ml after 3 min). The mean maximal serum concentration of lidocaine was higher in patients receiving lidocaine alone (1.77 +/- 0.03 microgram/ml) than in those receiving both anesthetics (0.99 +/- 0.45 microgram/ml). Furthermore, the mean plasma concentration of epinephrine 1 min after injection was significantly higher in patients receiving lidocaine alone (0.671 ng/ml) than in patients receiving both lidocaine and bupivacaine (0.323 ng/ml). The results of this study suggest that the combination of lidocaine with epinephrine and bupivacaine produces lower systemic levels of the anesthetic and epinephrine and a longer duration of activity than lidocaine with epinephrine alone for local dental anesthesia.     

Factors determining the doses of local anesthetic agents in unilateral inguinal hernia repair

Background

Today, local anesthesia is used in specialized hernia clinics in most cases. The technique for establishing local anesthesia for inguinal surgery may differ among surgeons. Few articles to date have mentioned the exact doses of local agents. This prospective study aimed to research the doses of local anesthetic agents needed in practice and determine the patient-related and other factors which affected those doses.

Methods

Three hundred consecutive patients who underwent an elective unilateral inguinal hernia repair were planned to be included in the study. Lidocaine as a short-acting, medium-lasting agent and bupivacaine 0.5% as a long-acting agent were chosen. Gender, age, body mass index (BMI), side of hernia (right/left), concomitant disease, history of hernia (primary/recurrent), type of hernia (indirect/direct), Gilbert class of hernia (1–6), size of hernia (small or medium/large or massive), hernia sac content (omentum/intestine), time shift (8 am to 4 pm/later than 4 pm), duration of operation, and institutional experience (first 150 cases vs. latter 150 cases) were recorded.

Results

There were 277 male and 23 female patients. The mean age was 49.73 years (range 16–83; median 50.00). The mean volume of total anesthetic agents (lidocaine + bupivacaine) was 19.79 ml (range 5.5–40; median 19.5). The mean volumes separately were 101.79 mg for lidocaine (range 30–200; median 100) and 48.12 mg for bupivacaine (range 12.5–110; median 50). The patients were discharged after a median time of 2 h postoperatively. Univariate analysis for the total dose of the two agents showed that younger age (≤60 vs. ≥61 years), larger size of hernia, longer duration of operation (≥61 vs. ≤60 min), recurrent hernia, hernia sac content (omentum > intestine), and higher BMI (≥25.1 vs. ≤25.0) were significant parameters. On the other hand, BMI, recurrent hernia, size of hernia, and omentum in the hernia sac were factors that significantly affected the mean lidocaine dose. Higher BMI and recurrent hernia also caused a higher need for bupivacaine. In addition, significantly lower doses of bupivacaine was used in older patients. The significant independent parameters in the multivariate analysis were duration of operation, sac content, and BMI for lidocaine dose, whereas the duration of operation and sac content were determinative for the sum volume of the two agents. None of the recorded parameters were found to be significant for bupivacaine dose in the logistic regression.

Conclusions

This prospective study showed, again, the feasibility of local anesthesia in elective inguinal hernia repair in all patient groups with different characteristics. The mean and maximum doses of local anesthetic agents were well within safety limits, even in recurrent and large hernias. Younger age, large hernias, recurrent hernias, omental mass in the hernia sac, high BMI, and duration of operation might be the factors affecting local anesthetic doses. The significant independent parameters in the multivariate analysis were duration of operation, sac content, and BMI for lidocaine dose, whereas the duration of operation and sac content were determinative for the sum volume of lidocaine and bupivacaine.     

Transient Neurologic Symptoms after Spinal Anesthesia: A Lower Incidence with Prilocaine and Bupivacaine than with Lidocaine

Background: Recent evidence suggests that transient neurologic symptoms (TNSs) frequently follow lidocaine spinal anesthesia but are infrequent with bupivacaine. However, identification of a short-acting local anesthetic to substitute for lidocaine for brief surgical procedures remains an important goal. Prilocaine is an amide local anesthetic with a duration of action similar to that of lidocaine. Accordingly, the present, prospective double-blind study compares prilocaine with lidocaine and bupivacaine with respect to duration of action and relative risk of TNSs.

Methods: Ninety patients classified as American Society of Anesthesiologists physical status I or II who were scheduled for short gynecologic procedures under spinal anesthesia were randomly allocated to receive 2.5 ml 2% lidocaine in 7.5% glucose, 2% prilocaine in 7.5% glucose, or 0.5% bupivacaine in 7.5% glucose. All solutions were provided in blinded vials by the hospital pharmacy. Details of spinal puncture, extension and regression of spinal block, and the times to reach discharge criteria were noted. In the evening of postoperative day 1, patients were evaluated for TNSs by a physician unaware of the drug administered and the details of the anesthetic procedure.

Results: Nine of 30 patients receiving lidocaine experienced TNSs, 1 of 30 patients receiving prilocaine (P = 0.03) had them, and none of 30 patients receiving bupivacaine had TNSs. Times to ambulate and to void were similar after lidocaine and prilocaine (150 vs. 165 min and 238 vs. 253 min, respectively) but prolonged after bupivacaine (200 and 299 min, respectively; P < 0.05).     

Comparison of hemodynamic and anesthetic effects of hyperbaric bupivacaine and tetracaine in spinal anesthesia

Purpose.To compare the anesthetic and hemodynamic effects and the predictive factor of anesthesia level of commonly used preparations of hyperbaric bupivacaine and tetracaine in spinal anesthesia. Methods.Two hundred patients aged 40 to 75 years with ASA physical status I or II were anesthetized spinally via the L4–5 interspace using 0.5% hyperbaric bupivacaine in 7.27% glucose (Bupivacaine group, n = 100) or 0.5% hyperbaric tetracaine dissolved in a 10% glucose solution (Tetracaine group, n = 100) in a lateral position. The volume of anesthetic used was decided by the resident according to the surgical procedure. Patients were returned to the supine position immediately after drug injection. Blood pressure, heart rate, and anesthesia level tested by cold sensation were measured for 30min. Results.Blood pressure and heart rate decreased significantly but without any differences between the groups. The volume of drug used was significantly larger in the Bupivacaine group (2.6 ± 0.5ml) than in the Tetracaine group (2.1 ± 0.4ml) to obtain the same maximum anesthesia level. The time to reach the maximum anesthesia level was significantly longer in the Bupivacaine group (18 ± 7min) than in the Tetracaine group (15 ± 6min). The volume of the drug was the only predictive factor of the maximum anesthesia level in both groups: Level (as expressed by the number of anesthetized segments from S5 to cephalad) = 1.55 × (volume in ml) + 13.06 in the Bupivacaine group, and 2.59 × (volume) + 11.46 in the Tetracaine group. Conclusion.In spinal anesthesia, hyperbaric tetracaine in 10% glucose induced a faster and higher spread of anesthesia than hyperbaric bupivacaine in 7.27% glucose without any differences in hemodynamics.     

The effect of preemptive analgesia with bupivacaine on postoperative pain of inguinal hernia repair under spinal anesthesia: a randomized clinical trial

Purpose

In the absence of any study on the use of bupivacaine as a long acting local anesthetic for the purpose of inducing preemptive analgesia in patients undergoing inguinal hernia repair under spinal anesthesia, this study was conducted to provide some evidence for possible benefits of such practice.

Methods

In this randomized clinical trial, local infiltration of bupivacaine in patients undergoing inguinal hernia repair under spinal anesthesia was compared with placebo. The patients were randomly divided to two groups of 30 including the case group who received 10 cc of 0.5 % bupivacaine and the control group who received 10 cc of normal saline in the operation site before surgical incision. At the end of spinal block effect, patients were followed for symptoms of pain intensity according to numerical rating scale method, nausea, vomiting and opioid use for 24 h past the operation.

Results

The pain scores, nausea, vomiting and postoperative opioid use were 69.6, 76.5, 83.2 and 80 % respectively lower in first 24 h among the case group (P < 0.001, P = 0.005, P = 0.001 and P < 0.001). The number of patients with at least one analgesic request in first 24 h after operation was 64.2 % lower in case group, while time of first analgesic request was 67 % longer in treatment group (P < 0.001 and P < 0.001).

Conclusion

The pre-operative local infiltration of bupivacaine reduces pain, nausea, vomiting and opioid use in the first 24 h after inguinal hernia surgery under spinal anesthesia. Therefore, further evaluation of the efficacy of this technique as a modality of preemptive analgesia is suggested.     

Systemic Safety of Liposomal Bupivacaine in Simultaneous Bilateral Total Knee Arthroplasty

Background

Intraoperative periarticular injections (PAIs) with local anesthetic are an important component of multimodal pain control in total joint arthroplasty. Liposomal bupivacaine is an extended-release formulation of bupivacaine designed to provide extended pain relief, approved for use in a single surgical site. The systemic safety profile for use in simultaneous bilateral TKA (bTKA) with a full dose in each knee has not been evaluated. The purpose of this study was to determine the safety and pharmacokinetics of bilateral full-dose PAI liposomal bupivacaine in the blood collected in patients undergoing simultaneous bTKA.

Comparative Analysis of Bupivacaine and Ropivacaine for Infiltration Analgesia for Bilateral Breast Surgery

Local anesthesia infiltration has been established as a preferred method of perioperative analgesia in many cosmetic operations. In an attempt to maximize the risk-benefit ratio of local anesthesia, a study was conducted to compare efficacy of two local anaesthetic agents. Bupivacaine was compared to ropivacaine in a bilaterally symmetrical breast surgery model. A local anaesthetic solution containing either bupivacaine or ropivacaine was infiltrated into each of the breasts of 15 patients undergoing either breast augmentation or breast reduction. Both surgeon and patient were blinded to the nature of local anaesthetic agent injected. Patients were requested to score their pain at 1, 2, 6, and 10 hours after surgery on a visual analog scale. The results were analyzed statistically using a cross-sectional time-series regression model employing the random effects option of the xtreg command from Strata Release 6 statistical software. We found that overall analgesia achieved with bupivacaine and ropivacaine infiltrations was not statistically different. The use of a higher dose of ropivacaine is likely to have removed the clinical advantage noted for the bupivacaine group. There was, however, a statistical and clinical difference in the efficacy of local anaesthetic infiltration of both agents in breast augmentation patients as compared to breast reduction patients, local anaesthetic being less effective in patients who had submuscular breast augmentation than in patients who had breast reduction. In view of these findings, it appears reasonable to recommend the use of ropivacaine in high-dose infiltration breast analgesia, as it is reported to be less cardiotoxic than bupivacaine. Serious attention needs also to be given to the adequacy of field infiltration of local anesthesia in submuscular breast augmentation.     

Regional nerve block for femoropopliteal and tibial arterial reconstructions

Thirteen high-risk patients underwent lower extremity revascularization anesthetized with a regional nerve block technique. The sciatic, femoral, and obturator nerves were infiltrated with 1% lidocaine and 0.25% bupivacaine. Eight femoropopliteal and five femorotibial bypasses were performed for limb salvage (11 patients), disabling claudication (one patient), and popliteal artery aneurysm (one patient). Analgesia was adequate with only one patient who needed supplemental nitrous oxide. One patient died on the sixth postoperative day of a myocardial infarction. Regional nerve block is an effective anesthetic technique that should be considered if general or spinal anesthesia is inappropriate.     

Anesthetic Efficacy of a Combination of 0.9 M Mannitol Plus 68.8 mg of Lidocaine With 50 μg Epinephrine in Inferior Alveolar Nerve Blocks: A Prospective Randomized,Single Blind Study

The purpose of this prospective randomized, single blind study was to determine the anesthetic efficacy of 68.8 mg of lidocaine with 50 μg epinephrine compared to 68.8 mg lidocaine with 50 μg epinephrine plus 0.9 M mannitol in inferior alveolar nerve (IAN) blocks. Forty subjects randomly received 2 IAN blocks consisting of a 1.72-mL formulation of 68.8 mg lidocaine with 50 μg epinephrine and a 5-mL formulation of 68.8 mg lidocaine with 50 μg epinephrine (1.72 mL) plus 0.9 M mannitol (3.28 mL) in 2 separate appointments spaced at least 1 week apart. Mandibular anterior and posterior teeth were blindly electric pulp tested at 4-minute cycles for 60 minutes postinjection. No response from the subject to the maximum output (80 reading) of the pulp tester was used as the criterion for pulpal anesthesia. Total percent pulpal anesthesia was defined as the total of all the times of pulpal anesthesia (80 readings), for each tooth, over the 60 minutes. One hundred percent of the subjects had profound lip numbness with both inferior alveolar nerve blocks. The results demonstrated that the 5 mL-formulation of 68.8 mg lidocaine with 50 μg epinephrine plus 0.9 M mannitol was significantly better than the 1.72-mL formulation of 68.8 mg lidocaine with 50 μg epinephrine for all teeth, except the lateral incisor. We concluded that adding 0.9 M mannitol to a lidocaine with epinephrine formulation was significantly more effective in achieving a greater percentage of total pulpal anesthesia (as defined in this study) than a lidocaine formulation without mannitol. However, the 0.9 M mannitol/lidocaine formulation would not provide 100% pulpal anesthesia for all the mandibular teeth.Key Words: Inferior alveolar nerve block, Lidocaine, MannitolThe inferior alveolar nerve (IAN) block is the most frequently used injection technique for achieving local anesthesia for mandibular restorative and surgical procedures. However, the IAN block does not always result in successful pulpal anesthesia.^1–6 Failure rates (never achieving 2 consecutive 80 readings with the electric pulp tester) of 10 to 39% have been reported.¹ A possible reason for failure is the perineurial barrier around the nerve may not allow complete diffusion of the anesthetic solution into the nerve trunk.Previous studies by Wolf et al⁷ and Smith et al⁸ demonstrated that lidocaine with epinephrine in combination with 0.5 M mannitol significantly improved the success of the IAN block (defined as the total of all the times of pulpal anesthesia [80 readings], for each tooth, over the 60 minutes) in asymptomatic subjects. Kreimer et al⁹ found, for mandibular posterior teeth in patients with symptomatic irreversible pulpitis, that the addition of 0.5 M mannitol to 1.9 mL of lidocaine with epinephrine resulted in a statistically higher success rate (success was defined as no or mild pain on visual analog scale [VAS] recordings) upon endodontic assess or instrumentation when compared to a lidocaine formulation without mannitol. The proposed mechanism is that mannitol opens the perineurial membrane to allow for enhanced penetrability for lipophilic compounds,¹⁰ and it may affect nerve conduction.¹¹However, 100% pulpal anesthesia was not obtained by Wolf et al,⁷ Smith et al,⁸ or Kreimer et al.⁹ Perhaps increasing the molarity of mannitol from 0.5 M to 0.9 M could potentially allow the anesthetic solution to permeate the nerve trunk in greater amounts, thereby increasing anesthetic efficacy. The purpose of this prospective randomized, single blind study was to determine the anesthetic efficacy of 68.8 mg of lidocaine with 50 μg epinephrine compared to 68.8 mg lidocaine with 50 μg epinephrine plus 0.9 M mannitol in IAN blocks. Pain of injection and postoperative pain were also studied.     

Anesthetic Efficacy of a Combination of 0.5 M Mannitol Plus 36.8 mg of Lidocaine With 18.4 μg Epinephrine in Maxillary Infiltration: A Prospective,Randomized, Single-Blind Study

The purpose of this prospective, randomized, single-blind study was to determine the anesthetic efficacy of lidocaine with epinephrine compared to lidocaine with epinephrine plus 0.5 M mannitol in maxillary lateral incisor infiltrations. Forty-one subjects randomly received 2 maxillary lateral infiltrations consisting of a 1.84-mL solution of 36.8 mg lidocaine with 18.4 μg epinephrine (control solution) and a 2.90-mL solution of 36.8 mg lidocaine with 18.4 μg epinephrine (1.84 mL) plus 0.5 M mannitol (1.06 mL) in 2 separate appointments spaced at least 1 week apart. The maxillary lateral incisor was blindly electric pulp–tested in 2-minute cycles for 60 minutes postinjection. No response from the subject to the maximum output (a reading of 80) of the pulp tester was used as the criterion for pulpal anesthesia. Total percent pulpal anesthesia was defined as the total of all pulpal anesthesia readings (at output of 80) over the 60-minute test period. Pain during solution deposition and postoperative pain were also measured. The results demonstrated that a 2.90-mL solution of 36.8 mg lidocaine with 18.4 μg epinephrine (1.84 mL) plus 0.5 M mannitol (1.06 mL) was not statistically significantly superior to a 1.84-mL solution of 36.8 mg lidocaine with 18.4 μg epinephrine. The pain of solution deposition was lower with the lidocaine/mannitol formulation. Postoperative pain was not statistically significantly different between the lidocaine/mannitol formulation and the lidocaine formulation without mannitol. We concluded that adding 0.5 M mannitol to a lidocaine with epinephrine formulation was not significantly more effective in achieving a greater percentage of total pulpal anesthesia (as defined in this study) than a lidocaine formulation without mannitol in the maxillary lateral incisor.Key Words: , Anesthesia, Mannitol, Lidocaine, Infiltration, Maxillary.Previous studies^1–19 have evaluated the success (ie, never achieving 1 or 2 consecutive 80 readings with the electric pulp tester) of maxillary infiltrations. When a volume of 1.8 mL or less was used with various anesthetic formulations, pulpal anesthetic success ranged from 62% to 100%.^1–19 Therefore, an infiltration injection may not always be 100% successful because of individual variations in response to the drug administered, operator differences, and variations in anatomy as well as tooth position.Previous studies by Wolf et al,²⁰ Smith et al,²¹ and Cohen et al²² demonstrated that lidocaine in combination with mannitol significantly improved the success of inferior alveolar nerve blocks (defined as the total of all the times of complete pulpal anesthesia as measured by the 80 readings, for each tooth, over 60 minutes) in asymptomatic subjects. Kreimer et al²³ found, for mandibular posterior teeth in patients with symptomatic irreversible pulpitis, that the addition of 0.5 M mannitol to 1.9 mL of lidocaine with epinephrine resulted in a statistically significantly higher success rate (success was defined as no or mild pain on a visual analog scale upon endodontic access or instrumentation) when compared to a lidocaine formulation without mannitol. The proposed mechanism of action is that mannitol opens the perineurial membrane to allow for enhanced penetration of lipophilic compounds,²⁴ and it may affect nerve conduction.²⁵ All previous studies have used combinations of lidocaine and mannitol for inferior alveolar nerve block anesthesia.^20–23No objective study has yet evaluated the combination of lidocaine and mannitol for infiltration anesthesia. The purpose of this prospective, randomized, single-blind study was to determine the anesthetic efficacy of a lidocaine/epinephrine formulation and to compare it to a lidocaine/epinephrine formulation with 0.5 M mannitol for maxillary lateral incisor infiltration. Pain during the injection and postoperative pain were also studied.     

Intrathecal fentanyl-induced pruritus is more severe in combination with procaine than with lidocaine or bupivacaine

BACKGROUND AND OBJECTIVES: Fentanyl is used as an additive to prolong intrathecal anesthesia with both lidocaine and low-dose bupivacaine in the outpatient setting to minimize voiding or discharge delays. Pruritus is the most common side effect. When using procaine as a substitute for lidocaine, we perceived an increased frequency and severity of pruritus. We compared prospectively the frequency and severity of itching with combinations of fentanyl with lidocaine, bupivacaine, and procaine. METHODS: After institutional review board approval, 135 patients requesting neuraxial anesthesia were asked to evaluate the presence and severity (using a 100 point verbal pruritus score [VPS]) of itching 30 minutes after injection of their spinal anesthetic, on arrival to the postanesthesia care unit (PACU), and at the time of resolution of their block. Choice of anesthetic drug and dose and the use of intravenous sedation was left to the discretion of the attending and resident anesthesiologist. RESULTS: Thirty-three patients received lidocaine and fentanyl, 47 received bupivacaine and fentanyl, and 55 received procaine and fentanyl. In the lidocaine group, 21% of patients experienced pruritus compared with 55% of the bupivacaine group and 55% of the procaine group (P =.003). The average VPS at 30 minutes postblock was 18.4 in the procaine group compared with 0 and 5.5 in the lidocaine and bupivacaine groups (P =.06). On admission to the PACU, it was 37 compared with 16 and 20 for lidocaine and bupivacaine, respectively (P =.006). CONCLUSION: Procaine produces a higher frequency of pruritus than that seen with lidocaine-fentanyl combinations and a greater severity of pruritus than seen with lidocaine-fentanyl and bupivacaine-fentanyl spinal anesthesia. Reg Anesth Pain Med 2001;26:252-256.