Adding clonidine to lidocaine for intravenous regional anesthesia prevents tourniquet pain.

Tourniquet pain often complicates the use of the pneumatic tourniquet during surgical procedures performed under IV regional anesthesia. Clonidine-containing local anesthetic solutions have better analgesic properties than plain solutions when used for spinal, epidural, or peripheral blocks. We tested the hypothesis that the addition of clonidine may improve the quality of IV regional anesthesia, especially tourniquet tolerance. Forty patients were allocated randomly in a double-blinded, randomized study to receive 40 mL of 0.5% lidocaine and either 1 mL of isotonic saline or clonidine (150 microg). A double-cuffed tourniquet was kept inflated until patients complained of pain, leading to release of the distal cuff. Pain at the tourniquet site, at the surgical site, and in the distal part of the arm was rated on a visual analog scale (VAS) and a verbal rating scale (VRS) every 15 min during tourniquet placement and every 15 min for 1 h after tourniquet deflation. Motor blockade, sedation, arterial pressure, and heart rate were also recorded. VAS and VRS scores were significantly lower in the clonidine group 30 and 45 min after tourniquet inflation. The tolerance for the distal tourniquet was also significantly longer in the clonidine group (median [range]: 22 [10-40] vs 10 [5-20] min; P < 0.05); motor blockade was comparable between the two groups. Pain was not different in the two groups after tourniquet release. The clonidine group experienced a higher degree of sedation. We conclude that clonidine improves tourniquet tolerance when added to a local anesthetic solution. IMPLICATIONS: A 150-microg dose of clonidine added to lidocaine improved tourniquet tolerance during IV regional anesthesia.     

Addition of dexmedetomidine to lidocaine for intravenous regional anaesthesia

BACKGROUND AND OBJECTIVE: The aim of this study was to determine the duration of onset and regression time of sensory and motor blocks, the quality of anaesthesia and postoperative analgesia by the addition of dexmedetomidine to local anaesthetic solution in intravenous regional anaesthesia (IVRA). METHODS: Forty patients scheduled for elective hand surgery participated in this prospective randomized double-blind study. The IVRA was achieved using 3 mg kg(-1) lidocaine diluted with saline to a total volume of 40 mL in the control group or 1 microg kg(-1) of dexmedetomidine + 3 mg kg(-1) lidocaine diluted with saline to a total volume of 40 mL in the dexmedetomidine group. The onset and regression times for sensory and motor blocks were recorded. Qualities of anaesthesia, intraoperative and postoperative analgesic requirements were noted. RESULTS: There was no difference between the groups with respect to sensory and motor blocks onset and regression time. The quality of anaesthesia was better in the dexmedetomidine group than the control group and the difference was statistically significant. Intraoperative and postoperative analgesic requirements were greater in the control group than in the dexmedetomidine group. CONCLUSIONS: Addition of dexmedetomidine to local anaesthetic solution in IVRA improved the quality of anaesthesia and decreased analgesic requirements, but had no effect on the sensory and motor blocks onset and regression times.     

Tramadol added to lidocaine for intravenous regional anesthesia

Sixty volunteers, divided into four groups of 15 each, received IV regional anesthesia of the upper limb with 40 mL tramadol 0.25%, sodium chloride 0.9%, lidocaine 0.5%, or 100 mg tramadol-containing lidocaine 0.5%. By using a double-blinded method, we tested the onset and recovery of sensory block at six sites of the forearm and hand as well as onset of complete motor block. The symptoms after deflation of the tourniquet were recorded. The onset and recovery of sensory block and the onset of motor block were similar in the tramadol and saline groups. However, in the Tramadol-Lidocaine Group, the speed of onset of sensory block was faster than in the Lidocaine Group. In the Tramadol and the Tramadol-Lidocaine Groups, the incidence of skin rash and painful or burning sensation at the injection site was increased. We conclude that tramadol 0.25% does not have a local anesthetic effect when used as a sole drug for IV regional anesthesia, but might modify the action of local anesthetic, providing a shorter onset time of sensory block. Implications: Tramadol, a centrally acting analgesic, might have local anesthetic properties, as do some opioid drugs. We demonstrated that 0.25% tramadol solution containing 100 mg tramadol is not effective as a sole drug, but may improve the action of 0.5% lidocaine for intravenous regional anesthesia. The increased incidence of side effects may limit the clinical use of tramadol.     

Addition of cisatracurium to lidocaine for intravenous regional anesthesia

STUDY OBJECTIVE: To determine the onset and regression time of motor and sensory block, and the quality of anesthesia and postoperative analgesia by the addition of cisatracurium to local anesthetic solution in small doses in intravenous regional anesthesia. DESIGN: Prospective, randomized, double-blind study. SETTING: University hospital. PATIENTS: 40 ASA physical status I and II patients undergoing elective hand surgery. INTERVENTIONS: Intravenous regional anesthesia was achieved using 3 mg/kg lidocaine diluted with saline to a total volume of 40 mL in the control group or 0.01 mg/kg of cisatracurium plus 3 mg/kg lidocaine diluted with saline to a total volume of 40 mL in the cisatracurium group. MEASUREMENTS: The onset and the regression time for sensory and motor block were recorded. Quality of anesthesia, intraoperative, and postoperative analgesic requirements were noted. Mean arterial pressure and heart rate were recorded every 5 minutes. MAIN RESULTS: The onset time of sensory and motor block in the cisatracurium group was shorter than in the control group, and the difference was statistically significant. The quality of anesthesia was better in the cisatracurium group than in the control group, and the difference was statistically significant. There was no difference between the two groups with respect to sensory block regression time. Motor block regression time was statistically longer in the cisatracurium group than in the control group. Analgesic requirement was greater in the control group than in the cisatracurium group. CONCLUSION: The addition of cisatracurium to lidocaine in intravenous regional anesthesia shortened the sensory and motor block onset times, improved the quality of anesthesia, and decreased analgesic requirements without causing clinical side effects.     

Low-dose lidocaine intravenous regional anesthesia for forearm fractures in children.

Intravenous (i.v.) regional anesthesia with low-dose lidocaine (1 mg/kg) lidocaine 1% diluted to 0.125% vol) provided safe and effective anesthesia for closed reductions of pediatric forearm fractures in outpatients. This procedure was prospectively evaluated in 44 children at The Nemours Children's Clinic, Jacksonville, Florida. Forty-three of 44 patients achieved adequate anesthesia (minimal or no pain on closed reduction). No significant complications were noted. Both patients and physicians were satisfied with the procedure. Patient pain was objectively assessed with visual pain charts in the preanesthesic, immediate postanesthetic, and postreduction time periods. The technique was both safe and effective in providing pain relief for reduction of forearm fractures in children.     

The analgesic effect of nitroglycerin added to lidocaine on intravenous regional anesthesia

We evaluated the analgesic effect of nitroglycerine (NTG) when added to lidocaine in IV regional anesthesia. Thirty patients undergoing hand surgery were randomly assigned to two groups. The control group (group C, n = 15) received a total dose of 40 mL with 3 mg/kg of lidocaine diluted with saline, and the NTG group (group NTG, n = 15) received an additional 200 mug NTG. Hemodynamic variables, tourniquet pain measured before and 1, 5, 10, 20, and 30 min after tourniquet inflation, and analgesic requirements were recorded during the operation. After the tourniquet deflation, at 1 and 30 min and 2 and 4 h, visual analog scale (VAS) score, time to first analgesic requirement, total analgesic consumption in the first 24 h after operation, and side effects were noted. Shortened sensory and motor block onset time (3.2 +/- 1.1 versus 4.5 +/- 1.2 min; P = 0.01 and 3.3 +/- 1.6 versus 5.2 +/- 1.8; P = 0.009 in group NTG and group C, respectively), prolonged sensory and motor block recovery times (6.8 +/- 1.6 versus 3.1 +/- 1.2 min P < 0.0001 and 7.3 +/- 1.3 versus 3.6 +/- 0.8 P < 0.0001 in group NTG and group C, respectively), shortened VAS scores of tourniquet pain (P = 0.023), and improved quality of anesthesia were found in group NTG (P < 0.05). VAS scores were lower in group NTG after tourniquet release and in the postoperative period (P = 0.001). First analgesic requirement time was longer in group NTG (225 +/- 74 min versus 39 +/- 33 min) than in group C (P < 0.0001). Postoperative analgesic requirements were significantly smaller in group NTG (P < 0.0001) but the side effects were similar in both groups. We conclude that the addition of NTG to lidocaine for IV regional anesthesia improves sensory and motor block, tourniquet pain, and postoperative analgesia without side effects.     

Quality of lidocaine analgesia with and without midazolam for intravenous regional anesthesia

Purpose

Midazolam has analgesic effects mediated by gamma aminobutyric acid-A receptors. This study was designed to evaluate the effect of midazolam on anesthesia and analgesia quality when added to lidocaine for intravenous regional anesthesia (IVRA).

Methods

Forty patients undergoing hand surgery were randomly assigned to two groups to receive IVRA. The control group received 3 mg/kg lidocaine 2% w/v diluted with saline to a total volume of 40 ml, and the midazolam group received an additional 50 μg/kg midazolam. Sensory and motor block onset and recovery times, tourniquet pain, intraoperative analgesic requirements, sedation, and anesthesia quality were recorded. Postoperative pain and sedation scores, time to first analgesic requirements, analgesic use in the first 24 h, and side effects were noted.

Results

Sensory and motor block onset and recovery times did not differ significantly between groups. Tourniquet pain scores were lower at 10, 15, 20, and 30 min (P < 0.0001) in the midazolam group. Three (15%) patients in the midazolam group required fentanyl for tourniquet pain compared with thirteen (65%) patients in the control group (P = 0.02). Patients in both groups received fentanyl once. Midazolam group showed that significantly less patients required diclofenac for postoperative analgesia (P < 0.01) and analgesic-free period during first postoperative 24 h was significantly longer (726.8 ± 662.8 min vs. 91.0 ± 35.9 min, P < 0.0001). Postoperative pain scores were lower (P < 0.0001) and sedation scores higher (P < 0.05) for the first 2 h in the midazolam group.

Conclusion

Addition of midazolam to lidocaine for IVRA improves anesthesia quality and enhances intraoperative and postoperative analgesia without causing side effects.     

Clonidine versus ketamine to prevent tourniquet pain during intravenous regional anesthesia with lidocaine

BACKGROUND AND OBJECTIVES: Both clonidine and ketamine have been found to prolong the action of local anesthetics through a peripheral mechanism. Our study compares the efficacy of a low dose of clonidine or ketamine separately added to intravenous regional anesthesia (IVRA) with lidocaine to prevent tourniquet pain. METHODS: We conducted a prospective randomized double-blinded study in 45 patients undergoing hand or forearm surgery, with anticipated duration exceeding 1 hour under IVRA. Proximal cuff inflation of a double tourniquet was followed by administration of 40 mL of lidocaine 0.5% and either saline, 1 microg/kg clonidine, or 0.1 mg/kg ketamine. When anesthesia was established, the inflation of the proximal and distal cuff was interchanged. Thereafter, tourniquet pain was rated on a visual analog scale (VAS) every 10 minutes. Intraoperatively, boluses of 25 microg fentanyl were provided for tourniquet pain treatment when required, and total fentanyl consumption was recorded. RESULTS: Patients receiving plain lidocaine persistently reported the highest pain scores among groups (P <.001) 20 minutes after distal cuff inflation. Differences between the groups with additional treatment were noted 50 minutes after distal cuff inflation and until the end of the observation, with significantly lower VAS ratings (P <.001 to P <.01) in ketamine-treated patients. Total fentanyl consumption was significantly decreased by ketamine (70.00 +/- 25.35 microg) or clonidine (136.67 +/- 39.94 microg) compared with the plain lidocaine group (215.33 +/- 52.33 microg) (P <.001 between all groups). CONCLUSIONS: The addition of clonidine 1 microg/kg or ketamine 0.1 mg/kg to lidocaine for IVRA delays the onset of unbearable tourniquet pain and decreases analgesic consumption for tourniquet pain relief, although ketamine has a more potent effect.     

Levobupivacaine 0.125% and lidocaine 0.5% for intravenous regional anesthesia in volunteers

BACKGROUND: Levobupivacaine, a long acting, amino-amide, local anesthetic, may offer advantages over lidocaine for intravenous regional anesthesia (IVRA). The objective of this investigation was to compare levobupivacaine to lidocaine for IVRA. METHODS: After institutional review board approval and informed consent, eight unpremedicated male American Society of Anesthesiologists (ASA) I-II volunteers received 40 ml of levobupivacaine 0.125% or lidocaine 0.5% for IVRA on separate days. Onset and regression of sensory anesthesia by pinprick, transcutaneous electrical stimulation (TES), and of motor function were tested before, during, and after release of the tourniquet. Central nervous system and cardiac side effects were evaluated after local anesthetic administration and tourniquet release. The tourniquet remained inflated for 30-45 min. RESULTS: Intravenous regional anesthesia with either agent provided surgical anesthesia. Sensory anesthesia to pinprick (lateral antebrachial cutaneous nerve) was faster with lidocaine at median 1.5 min. versus 12.5 min with levobupivacaine. Loss of sensation to TES occurred at median 22.5 and 27.5 min for lidocaine and levobupivacaine, respectively. Loss of motor function occurred earlier after lidocaine administration. After release of the tourniquet, return of sensation to TES, pinprick (ulnar nerve), and return of motor function occurred later with levobupivacaine at median 25, 15, and 21.25 versus 10, 4.5, and 10 min with lidocaine. Central nervous system side effects were absent in volunteers given levobupivacaine, but five of eight volunteers given lidocaine experienced mild side effects. No cardiac events were noted. CONCLUSIONS: Levobupivacaine 0.125% may be an alternative to lidocaine 0.5% for IVRA. Longer lasting analgesia after release of the tourniquet may be caused by a more profound and prolonged tissue binding effect of levobupivacaine.     

Addition of atracurium to lidocaine for intravenous regional anaesthesia

This study was undertaken to examine the possible clinical advantages of using muscle relaxant with intravenous regional anaesthesia, (IVRA). Forty unpremedicated adult patients undergoing hand surgery were randomly allocated to receive either 40 ml 0.5% lidocaine or 40 ml 0.5% lidocaine with 2 mg of atracurium. The atracurium group of patients had a significantly greater degree of muscle relaxation, easier reduction of fractures, and better operative conditions ( P < 0.01). Less pain was also reported during surgery ( P < 0.025), and 5 and 15 min after release of the tourniquet ( P < 0.01). Clinically, there was no difference in the speed of onset of block between the two groups. It is concluded that the addition of atracurium to lidocaine improves the operating condition during IVRA with less pain during and after surgery.     

Ketamine for intravenous regional anesthesia

We studied ketamine intravenous regional anesthesia of the upper extremity in volunteers using concentrations of 0.5%, 0.3%, and 0.2%. Ketamine 0.5 and 0.3% produced adequate intravenous regional anesthesia. Anesthesia was inadequate when a 0.2% concentration was used. However, although the 0.3% concentration provides complete sympathetic, sensory, and motor blockade when injected into the isolated extremity, unpleasant psychotomimetic effects after the release of the tourniquet limit the usefulness of this use of ketamine. Ketamine cannot be recommended for intravenous regional anesthesia unless these unpleasant side effects are abolished or controlled by means of pharmacologic adjuvants.     

Non-alkalinized and alkalinized 2-chloroprocainevs lidocaine for intravenous regional anesthesia during outpatient hand surgery

PURPOSE: Chloroprocaine should be an ideal agent for intravenous regional anesthesia (IVRA) because of its rapid onset and ester hydrolysis. Raising the pH of local anesthetics may increase the speed of onset and the intensity of nerve blocks. We compared plain and alkalinized 2-chloroprocaine 0.5% with lidocaine for IVRA. METHODS: In two separate double-blind studies, 78 patients scheduled for daycare hand surgery were randomized to receive 40 mL plain 2-chloroprocaine 0.5%, alkalinized 2-chloroprocaine 0.5% or lidocaine 0.5% for IVRA. Time to sensory and motor block, need for supplemental analgesia, and side effects were compared. RESULTS: There was no difference in time to sensory or motor block in either group. Patients who received plain chloroprocaine required more supplemental opioid and had a higher incidence of metallic taste and of hives than patients who received lidocaine (P < 0.05). Comparing alkalinized chloroprocaine with lidocaine, there was no difference found with respect to opioid supplementation, CNS side effects, or incidence of hives. CONCLUSION: In conclusion, alkalinized chloroprocaine was found to be an effective agent for IVRA but no benefit over lidocaine was detected. Plain chloroprocaine for IVRA produced more minor side effects than lidocaine.     

Ropivacaine 0.2% and lidocaine 0.5% for intravenous regional anesthesia in outpatient surgery

BACKGROUND: A longer-acting local anesthetic agent, such as ropivacaine, may offer advantages over lidocaine for intravenous regional anesthesia. The objectives of this study were to evaluate whether the findings of volunteer investigations with intravenous regional anesthesia with ropivacaine (which have shown prolonged analgesia after release of the tourniquet) translates into improved pain control after surgery. METHODS: With Human Investigation Committee approval and a double-blind study design, 20 healthy patients with American Society of Anesthesiologists physical status I or II classification who were scheduled to undergo forearm and hand surgery were randomly assigned to administration of 40 ml of either 0.2% ropivacaine or 0.5% lidocaine for intravenous regional anesthesia. Evidence of central nervous system side effects, such as lightheadedness, tinnitus, and metallic taste, as well as cardiac arrhythmias, were evaluated and treated (if necessary) after local anesthetic administration, before and during surgery, and after release of the tourniquet until discharge from the postanesthesia care unit. Regression of sensory anesthesia in the nerve distributions of the forearm and hand was recorded. Verbal numerical pain scores were monitored and quantified until the patients were discharged to home from the postanesthesia care unit. Patient pain scores, side effect profiles, time to first oral intake, and total amount of oral analgesics were recorded 24 h postoperatively. RESULTS: Intravenous regional anesthesia with 0.2% ropivacaine and 0.5% lidocaine provided equivalent levels of surgical anesthesia. After release of the tourniquet, the first evidence for return of sensation in the distribution of the five peripheral nerves occurred later in the ropivacaine group (median, 20 min; range, 15-40 min) than in the lidocaine group (median, 1 min; range, 1-25 min). Verbal numerical pain scores were significantly lower at the time of admission, whereas during the remainder of the postanesthesia care unit stay and later at home, the difference in verbal numerical pain scores between the two groups was no longer statistically significant. CONCLUSIONS: Ropivacaine 0.2% may be an alternative to 0.5% lidocaine for intravenous regional anesthesia in the outpatient surgical setting. Longer-lasting analgesia in the immediate postoperative period may be due to a more profound and prolonged tissue binding effect of ropivacaine.     

Addition of clonidine to 0.5% lidocaine for intravenous locoregional anesthesia

OBJECTIVE: Evaluate the effect of the addition of clonidine to lidocaine on postoperative pain after intravenous regional anaesthesia. STUDY DESIGN: Double blind prospective study. PATIENTS AND METHODS: Forty-five patients were randomly allocated to two groups: group 1 (n = 25) receiving 3 mg.kg-1 of lidocaine 0.5% added to saline and group 2 (n = 20) receiving 3 mg.kg-1 of lidocaine 0.5% added to clonidine (150 micrograms). Postoperative analgesia was assessed using a visual analogue pain score (VAPS) and the time to first analgesic request. The incidence of side effects after tourniquet release was noted. Analysis of variance, Kruskall Wallis and chi 2 tests were used for statistical analysis. A p-value of < 0.05 was considered significant. RESULTS: Age, ASA class, duration and type of surgery, tourniquet time and sensory block duration were comparable for the two groups. The time to first antalgic request after deflation of tourniquet was similar in the two groups (38 +/- 15 min versus 44 +/- 19 min), while VAPS score was lower (p < 0.05) in the clonidine group (5.2 versus 6.8). The incidence of side effects was comparable in the two groups. CONCLUSION: The addition of clonidine (150 micrograms) to lidocaine for intravenous regional anaesthesia improved postoperative analgesia but in a limited and short-lasting manner.     

Comparison of ropivacaine 0.2% and 0.25% with lidocaine 0.5% for intravenous regional anesthesia

Study ObjectiveTo compare the anesthetic effects of two different concentrations and doses of ropivacaine (0.2% and 0.25%) with those of a conventional dose of lidocaine 0.5%.DesignProspective, randomized, double-blinded, clinical investigation.SettingLarge metropolitan university hospital.Patients66 adult ASA physical status I and II patients undergoing forearm and hand surgery.InterventionsPatients were randomly allocated to three groups to receive intravenous regional anesthesia (IVRA). Study groups were: ropivacaine 0.2% (Group I, n = 22), ropivacaine 0.25% (Group II, n = 22), and lidocaine 0.5% (Group III, n = 22).MeasurementsTourniquet tolerance times and regression of sensory analgesia were noted. Verbal numerical pain scores (VNS), cumulative analgesic consumption, and side effects were recorded during surgery and postanesthesia care unit (PACU). Time to first pain medication intake and number of patients receiving analgesics in the PACU were recorded.Main ResultsAdditional tolerance times for the distal tourniquet were significantly higher in the ropivacaine 0.25% group than the other two groups. Regression of sensory anesthesia was fastest in the lidocaine group. During the PACU stay, VNSs were significantly lower in the first 20 minutes in the ropivacaine groups than the lidocaine group. Time to first intake of pain medication in the PACU was soonest in the lidocaine group. The number of patients given analgesics in the PACU was highest in the lidocaine group. The number of patients taking > two tablets of tramadol was significantly lowest in the ropivacaine 0.25% group. No serious side effects were observed in any study group.ConclusionLonger tolerance times for the distal tourniquet, prolonged analgesia after tourniquet release, and lower analgesic requirements postoperatively make ropivacaine 0.2% and 0.25% an alternative to lidocaine for IVRA.