Comparison of the effect of EMLA cream, subcutaneous ring anaesthesia and a double cuff technique in the prevention of tourniquet pain

Femoral artery block (FAB) attenuates thigh tourniquet-induced hypertension: a prospective randomized, double-blind, placebo-controlled trial

INTRODUCTION

Prolonged tourniquet inflation during surgery frequently leads to tourniquet hypertension (TH), which is thought to arise from compression of A-δ fibers leading to sympathetically mediated C fiber activation. In the lower extremity, C fibers and other sympathetic nerve fibers are carried along the femoral artery. We hypothesized that blockade of these fibers at the femoral artery would decrease the incidence of TH.

METHODS

Thirty American Society of Anesthesia 1-3 patients aged 18-75 undergoing total ankle arthroplasty were randomized to receive 15 mL of injectate (mepivacaine 1.5% or saline placebo) at the anteromedial aspect of the common femoral artery at the level of the inguinal crease under ultrasound guidance. Both groups received preoperative popliteal sciatic and saphenous nerve blocks for analgesia and a standardized general anesthetic. Esmolol was administered if systolic blood pressure rose >30% above baseline. Incidence of TH was the primary outcome.

RESULTS

TH was present in 93.3% of sham patients versus 33.3% of block patients. Mean systolic pressure at 120 min and 150 min of tourniquet time was significantly higher in the sham group compared with the block group. Esmolol requirement (95.3+107.6 v 8.0+14.2, p=<0.001) was also significantly higher in the sham group. No differences were noted in pain scores or opioid consumption, and no patient experienced sensory or motor block of the femoral nerve.

DISCUSSION

Under these experimental conditions, injection of local anesthetic around the femoral artery reduced the incidence of TH and intraoperative esmolol requirement.

TRIAL REGISTRATION NUMBER

www.clinicaltrials.gov (NCT03390426; December 28, 2017).

A randomized controlled trial to assess the effect of a ketamine infusion on tourniquet hypertension during general anaesthesia in patients undergoing upper and lower limb surgery

BACKGROUND

Tourniquet hypertension arising from tourniquet inflation remains a primary concern to the anaesthetist. One drug commonly used to manage tourniquet hypertension is ketamine. No studies have examined the effect of ketamine on tourniquet hypertension for a period of more than one hour or an infusion of the same.

OBJECTIVE

To compare the effect of an intravenous infusion of ketamine versus placebo on tourniquet induced hypertension in patients undergoing upper and lower limb surgery under general anaesthesia.

METHODS

Forty six adult patients scheduled for upper and lower limb surgery under general anaesthesia were randomized into two equal groups. The ketamine group received an intravenous bolus of 0.1mg/kg of ketamine followed by an infusion of 2ug/kg/min. The saline group received an intravenous bolus of physiological saline followed by an infusion of saline. All the patients were reviewed post-operatively. Data of the baseline characteristics, haemodynamic changes, post-tourniquet pain and side effects were collected. If post-tourniquet pain was present post-operatively, a visual analogue scale (VAS) was used to assess its severity.

RESULTS

46 patients successfully completed the trial. There were no significant differences between the groups for baseline patient demographics. The incidence of tourniquet hypertension was higher in the saline group (26.1%) compared with ketamine group (4.6%) with a 95% confidence interval. The difference was shown to be statistically significant ('P'<0.05). There was an increase in systolic blood pressure after 60 minutes of tourniquet inflation in the saline group but the difference was not statistically significant('P'>0.866). There were no significant differences between the groups as regards diastolic blood pressure and heart rate. VAS scores did not differ between the two groups. Statistically, there was no difference found between the two groups. Side effects were minimal in the ketamine group whilst in the saline group, nausea and vomiting were predominant but were also not statistically significant.

CONCLUSION

Based on the results of this study, there was a difference in the proportion of tourniquet hypertension between the ketamine and saline groups for patients undergoing upper and lower limb orthopaedic surgery under general anaesthesia.

The analgesic effect of nitroglycerin added to lidocaine on quality of intravenous regional anesthesia in patients undergoing elective forearm and hand surgery

PURPOSE

To evaluate the effect of nitroglycerine (NTG) on sensory and motor block onset and recovery time as well as the quality of tourniquet pain relief, when added to lidocaine (LID) for intravenous regional anesthesia in elective forearm and hand surgery.

METHODS

A randomized double-blinded clinical trial was performed on 40 patients that were randomly allocated into two groups received lidocaine 3 mg/kg with NTG 200 µg or received only lidocaine 3 mg/kg as the control.

RESULTS

There was no difference between the two study groups in hemodynamic parameters before tourniquet inflation, at any time after inflation and after its deflation. There was no difference in the mean of pain score over time between the two groups. The onset time of sensory and motor blockades was shorter in the group received both LID and NTG. The mean recovery time of sensory blockade was longer in the former group. The frequency of opioid injections was significantly lower in those who administered LID and NTG.

CONCLUSION

The adjuvant drug of NTG when added to LID is effective in improving the overall quality of anesthesia, shortening onset time of both sensory and motor blockades, and stabling homodynamic parameters in hand and forearm surgery.

Comparison of pain perceived when using pneumatic or silicone ring tourniquets for local anaesthetic procedures in the upper limb

The aim of this study was to evaluate the level of pain felt when silicone ring and pneumatic tourniquets were applied to the upper arm and to determine which was more suitable for use in local anaesthetic procedures. Pain was measured using a visual analogue score pain scale on application and at 1, 5, and 10 minutes in 30 volunteers. Volunteers experienced significantly more pain on application and at 1 and 5 minutes with the silicone ring tourniquet. This difference in pain was most marked on application. Two volunteers could not tolerate application of the silicone ring tourniquet. We conclude that the silicone ring tourniquet would not be suitable for local anaesthetic procedures in the upper limb due to the severe pain experienced on application, which may reduce the patients' confidence and adversely affect their experience of the procedure. The pneumatic tourniquet is more suitable for local procedures.

Does the use of ketamine or nitroglycerin as an adjuvant to lidocaine improve the quality of intravenous regional anesthesia?

Aims:

To compare and evaluate the effect of adding ketamine or nitroglycerin (NTG) as adjuncts to lidocaine for intravenous regional anesthesia (IVRA) on intraoperative and postoperative analgesia, sensorial and motor block onset times, and tourniquet pain.

Settings and Design:

A prospective, randomized, double-blind study was carried out.

Materials and Methods:

Seventy-five patients undergoing hand surgery were divided into three groups as follows: control group receiving lidocaine 2%, LK group receiving lidocaine 2% with ketamine, and LN group administered lidocaine 2% with NTG. Sensory and motor blocks' onset and recovery times were recorded. Visual analog scale (VAS) for tourniquet pain was measured after tourniquet application and it was also used to measure postoperative pain. Analgesic consumption for tourniquet pain and postoperatively were recorded.

Results:

Sensory block onset times were shorter in the LK (4.4 ± 1.2 minutes) and LN (3.5 ± 0.9 minutes) groups compared with the control group (6.5 ± 1.1 minute) (P < 0.0001) and motor block onset times were shorter in the LK (7.3 ± 1.6 minutes) and LN (3.6 ± 1.2 minutes) groups compared with the control group (10.2 ± 1.5 minutes) (P< 0.0001). Sensory recovery time prolonged in the LK (6.7 ± 1.3 minutes) and LN (6.9 ± 1.1 minutes) groups compared with the control group (5.3 ± 1.4 minutes) (P = 0.0006 and < 0.0001, respectively). Motor recovery time prolonged in the LK (8.4 ± 1.4 minutes) and LN (7.9 ± 1.1 minutes) groups compared with the control group (7.1 ± 1.3 minutes) (P = 0.0014 and 0.023, respectively). The sensory and motor block onset times were also shorter in LN group than in the LK group (3.5 ± 0.9 versus 4.4 ± 1.2 minutes, P=0.004; and 3.6 ± 1.2 versus 7.3 ± 1.6 minutes, P < 0.0001, respectively). The amount of fentanyl required for tourniquet pain was less in adjuvant groups when compared with control group. It was 13.6 ± 27.9 and 27.6 ± 34.9 µg in LK group and LN groups, respectively, versus 54.8 ± 28 µg in the control group. VAS scores of tourniquet pain were higher at 10, 20, 30, 40 minutes in the control group compared with the other study groups (P < 0.0001). It was also higher in LN group compared with LK group at 30 and 40 minutes (P < 0.001). Postoperative VAS scores were higher for the first 4 h in control group compared with the other study groups (P< 0.0001).

Conclusions:

The adjuvant drugs (ketamine or NTG) when added to lidocaine in IVRA were effective in improving the overall quality of anesthesia, reducing tourniquet pain, increasing tourniquet tolerance and improving the postoperative analgesia in comparison to the control group. Ketamine as an adjuvant produced better tolerance to tourniquet than the other groups. NTG as an adjuvant produced faster onset of sensory and motor blockades in comparison to other groups.

Tourniquet use in upper limb surgery

Tourniquets are compressive devices that occlude venous and arterial blood flow to limbs and are commonly used in upper limb surgery. With the potential risk of complications, there is some debate as to whether tourniquets should continue to be routinely used. In this review, we first look at the different designs, principles, and practical considerations associated with the use of tourniquets in the upper limb. The modern pneumatic tourniquet has many design features that enhance its safety profile. Current literature suggests that the risk of tourniquet-related complications can be significantly reduced by selecting cuff inflation pressures based on the limb occlusion pressure, and by a better understanding of the actual level of pressure within the soft tissue, and the effects of cuff width and contour. The evidence behind tourniquet time, placement, and limb exsanguination is also discussed as well as special considerations in patients with diabetes mellitus, hypertension, vascular calcification, sickle cell disease and obesity. We also provide an evidence-based review of the variety of local and systemic complications that may arise from the use of upper limb tourniquets including pain, leakage, and nerve, muscle, and skin injuries. The evidence in the literature suggests that upper limb tourniquets are beneficial in promoting optimum surgical conditions and modern tourniquet use is associated with a low rate of adverse events. With the improvement in knowledge and technology, the incidence of adverse events should continue to decrease. We recommend the use of tourniquets in upper limb surgery where no contraindications exist.

Patient comfort during regional anesthesia

Regional anesthesia has many advantages, which include low cost, ease of administration, and avoidance of risks associated with general anesthesia. Injection of local anesthetic via a needle as part of a regional anesthetic technique can be a stressful experience. The goal is to produce a relaxed patient who is comfortable and cooperative throughout the duration of surgery. The topics of regional anesthetic techniques, drug combinations, and adjunct measures such as sedation have been described extensively in the literature. The issue of patient comfort has not been reviewed in its entirety. This review seeks to collate known information in a systematic format and provide a framework for patient comfort during regional anesthesia.

[Is a blockade of the lateral cutaneous nerve of the thigh an alternative to the classical femoral nerve blockade for knee joint arthroscopy? A randomised controlled study]

BACKGROUND

Gaps in the distribution area of the lateral femoral cutaneous nerve (LFCN) are assumed to be the reason for pain caused by a thigh tourniquet when performing a femoral nerve (FN) block according to Winnie. The aim of the study was to evaluate if a direct single blockade of the LFCN in patients undergoing knee surgery resulted in a better tolerance to the tourniquet with equally good analgesic quality during surgery.

METHODS

A total of 40 patients undergoing knee arthroscopy received a proximal blockade of the sciatic nerve and randomly either an FN or an LFCN block. Practicability, onset time, quality of sensory and motor block, and clinical effectiveness during tourniquet and surgery were assessed.

RESULTS

Stimulation time was significantly longer in the LFCN than in the FN group. Quality of sensory and motor block was worse in the LFCN than the NF group. Of the LFCN patients 65% indicated troublesome paraesthesia or pain when a tourniquet was placed, compared to 35% of the FN patients. Of the LFCN patients 50% had pain during cutaneous incision, compared to none of the FN group. During the course of surgery, 70% of the LFCN patients needed supplemental systemic analgesia, but this was required by only 30% of the FN group.

CONCLUSION

An LFCN block is not a suitable alternative to an FN block for regional anaesthesia. For patients with contraindications for an FN block according to Winnie (e.g. vessel surgery in the groin) other more effective methods are available.

Does dexamethasone improve the quality of intravenous regional anesthesia and analgesia? A randomized, controlled clinical study

We investigated the anesthetic and analgesic effectiveness of adding dexamethasone to lidocaine for IV regional anesthesia (IVRA). Seventy-five patients undergoing ambulatory hand surgery were randomly assigned to one of three groups: group L received 3 mg/kg lidocaine, group LD received 3 mg/kg lidocaine + 8 mg dexamethasone, and group LDc received 3 mg/kg lidocaine for IVRA and 8 mg dexamethasone IV to the nonsurgical arm. IVRA was established using 40 mL of a solution. Visual analog scale and verbal pain scores were recorded intraoperatively and for 2 h postoperatively. Postoperative pain was treated with oral acetaminophen 500 mg every 4 h when visual analog scale score was more than 3. Time to request for the first analgesic and the total dose in the first 24 h were noted. Times to onset of complete sensory and motor block were similar in the 3 groups. The times to recovery of motor block (L = 8 [5.91-10.08] min, LD = 13 [6.76-20.19] min, LDc = 6 [4.44-8.43] min) and sensory block (L = 7 [5.21-10.30] min, LD = 12 [6.11-19.40] min and LDc = 6 [4.2-8.11] min) were longer in group LD (P < 0.05). Patients in group LD reported significantly lower pain scores and required less acetaminophen in the first 24 h after surgery. In conclusion, the addition of 8 mg dexamethasone to lidocaine for IVRA in patients undergoing hand surgery improves postoperative analgesia during the first postoperative day.

Does the Sciatic Nerve Approach Influence Thigh Tourniquet Tolerance During Below-Knee Surgery?

In this prospective, randomized, blinded study we assessed thigh tourniquet tolerance when a Labat's or a posterior popliteal approach of the sciatic nerve was used for below-knee surgery. One-hundred-twenty patients were divided into two groups of 60. A posterior popliteal (Group 1) or a Labat's (Group 2) sciatic nerve block was performed with 25 mL 1% mepivacaine + epinephrine 1:200,000. In both groups, a femoral nerve block was achieved. Patient comfort during block performance, sensory block, success rate, and thigh tourniquet tolerance were recorded. Performance of the block was significantly more comfortable in Group 1 than in Group 2 (P < 0.01). Completeness of the block at t(30 min.) and success rate were comparable in both groups. Thigh tourniquet pain increased with time in both groups. No statistically significant difference was observed between groups. We conclude that despite a complete sensory blockade of the posterior femoral cutaneous nerve in 91% of the patients, Labat's approach of the sciatic nerve provides no better thigh tourniquet tolerance than the popliteal approach. The popliteal approach is as efficient but more comfortable for the patient and is the preferred technique for below-knee surgery.

0.5% Versus 1.0% 2-Chloroprocaine for Intravenous Regional Anesthesia: A Prospective, Randomized, Double-Blind Trial

In this randomized prospective double-blind study we tested the hypothesis that compared with 40 mL chloroprocaine 0.5%, 40 mL chloroprocaine 1% results in an earlier onset to analgesia duration and improves distal tourniquet tolerance in 150 patients undergoing forearm surgery under IV regional anesthesia using a double-cuff technique, switching from the proximal to the distal cuff was performed if pain scores increased above 4 of 10. Switching to the distal cuff resulted in pain scores below 4 in 69% of patients in the 0.5% group and in 88% of patients in the 1% group (P = 0.047). In addition, both groups differed in the sustained effect on distal tourniquet pain (P = 0.020). Time between injection and onset to analgesia duration was 13 +/- 1 min in the 0.5% group and 11 +/- 1 min in the 1% group (P = 0.0006). On release of the tourniquet, signs of systemic local anesthetic toxicity occurred in 6 patients of the 0.5% group and 28 of the 1% group (P < 0.0001). We conclude that chloroprocaine 1% resulted in an earlier onset of analgesia and improved distal tourniquet tolerance. However, these beneficial effects must be weighed against a fourfold increase in side effects.

IMPLICATIONS

Compared to a standard dose of 40 mL 0.5% chloroprocaine, 40 mL 1% chloroprocaine resulted in an earlier onset of analgesia duration and improved distal tourniquet tolerance during IV regional anesthesia. These beneficial effects must be weighed against a fourfold increase in signs of systemic local anesthetic toxicity.

Tourniquet pain in a volunteer study: effect of changes in cuff width and pressure

This study examines the relationship between pneumatic tourniquet cuff size, occlusion pressure and the resulting pain. Two tourniquet cuff widths were used, a wide (14 cm) and a narrow cuff (7 cm). Twenty volunteers were divided into two groups for tourniquet application: a pressure group in which the tourniquet was inflated to a pressure equal to the systolic pressure + 100 mmHg, and a saturation group in which the tourniquet was inflated to 10 mmHg above the loss of arterial pulse, as indicated by cessation of pulse waveform on an oximeter. According to a randomised cross-over protocol, subjects were studied using wide and narrow cuffs simultaneously and/or successively on both arms. Pain was assessed by subjects by means of a visual analogue score (0-10 cm). Occlusion pressures were similar for all volunteers in the pressure group and significantly higher than those in the saturation group with both the wide and narrow tourniquets. The wide cuff data turned out to be significantly lower than the narrow cuff results. Subjects in the pressure group could tolerate pain with the narrow cuff for significantly longer than with the wide cuff. However, in the saturation group, volunteers tolerated the wide cuff for longer. Pain intensity increased more rapidly in those in the pressure group with the wide cuff than with the narrow cuff. In contrast, volunteers in the saturation group found the narrow cuff to be more painful than the wide cuff. In conclusion, this study has shown that a wide tourniquet cuff is less painful than a narrow cuff if inflated at lower pressures and at these lower pressures it is still effective at occluding blood flow.

[Locoregional intravenous anesthesia]

OBJECTIVE

To analyse current data on intravenous regional anaesthesia (IVRA), its benefits and drawbacks.

DATA SOURCES

Articles were obtained from a Medline search using the following search terms: 'intravenous regional anaesthesia', alone or combined with 'local anaesthetic agents', 'toxicity'.

STUDY SELECTION

Following articles in English and in French have been selected: main articles, original articles, update and review articles, letters to the editor and recent editorials.

DATA EXTRACTION

Physiopathological and pharmacological data were extracted for involved mechanisms and means for improving this technique.

DATA SYNTHESIS

IVRA is a reliable and efficient technique with a lower cost than general anaesthesia and well adapted for limb surgery in the ambulatory patient. Depending on the site of the surgical field, the pneumatic tourniquet is set either on the arm, forearm or wrist for the upper limb or thigh, calf or ankle for the lower limb. When set in periphery, less local anaesthetic agent is required. A wide tourniquet requires a lower inflation pressure than a double cuff tourniquet. A single cuff is as efficient as a dual cuff if shape, size and inflating pressure are appropriate. The limb occlusion pressure (LOP) is the minimal pressure required to occlude blood flow. It is assessed with either a pulse oximeter or Doppler for determination of the lowest cuff inflating pressure. The cuff is inflated to 50 mmHg above LOP. Oozing in the surgical field can be decreased by the re-exsanguination technique. Currently, lidocaine is the only local anaesthetic released in France for IVRA. Addition of a muscle relaxant, a NSAID or clonidine allows the dose of local anaesthetic agent to be decreased and improves postoperative analgesia.

Comparison of the effect of EMLA and semicircular subcutaneous anaesthesia in the prevention of tourniquet pain during plexus block anaesthesia of the arm

In 54 patients who were to undergo surgery of the upper extremity in plexus block anaesthesia the effect of 5 g EMLA (group E) on tourniquet pain was examined and compared with the effect of a semicircular subcutaneous anaesthesia using 10 ml 0.25% bupivacaine (group B) or 10 ml 1% mepivacaine (group M). Among the patients with satisfactory brachial plexus analgesia allowing for surgery (n = 51), the incidence of tourniquet pain was not significantly different between groups E, M and B. Notably, there was no significant difference in the time of tourniquet application. We conclude that topical application of EMLA is as effective as a semicircular subcutaneous anaesthesia with mepivacaine or bupivacaine in the prevention of tourniquet pain during brachial plexus anaesthesia.

A North American survey of intravenous regional anesthesia

One thousand questionnaires concerning the techniques and complications of intravenous regional anesthesia (IVRA) were sent to 900 American and 100 Canadian anesthesiologists. Of the 321 respondents, 86% perform IVRA regularly. A wide variation in device-related and clinical aspects was found, ranging from acceptable to falling outside published guidelines. Anesthesiologists perform a median of four upper-limb IVR procedures per month, most often using 50 mL of lidocaine 0.5% at tourniquet pressures of 250 mm Hg or 100 mm Hg greater than the systolic blood pressure. Forearm, thigh, and calf IVRA are occasionally used. Complications, reported infrequently in the literature, were reported by respondents, including mistaken deflation of the cuff; dysphoria, dizziness, or facial tingling; seizures; cardiac arrests; and deaths. Although there was no correlation between complications and deviation from traditional practice, we recommend that IVRA be performed following recognized protocols by anesthesiologists who are familiar with the technique and trained to treat its potential complications. We recommend a protocol for IVRA.

IMPLICATIONS

Intravenous regional anesthesia is a widely used anesthetic technique. A survey of 321 American and Canadian anesthesiologists indicates a wide variation in technique. Despite no correlation between complications and technique, the authors recommend that recognized protocols be used for this technique.

[Pneumatic tourniquets in orthopedics]

Pneumatic tourniquets, often used to provide a bloodless operating field, carry a risk of adverse effects. Limb exsanguination by gravitation is less aggressive than by mechanical means. Skin, muscles, nerves and vessels suffer maximally under tourniquet because of mechanical pressure, with both a sagittal force, responsible for compression and an axial force responsible for stretchening. All parts of the limb are therefore affected by ischaemia. The restarting of circulation will also increase lesions at the microcirculatory level, responsible for the "no reflow" phenomena. Transient reperfusion intervals are not necessarily beneficial. These effects will significantly contribute to the post tourniquet sensory motor injuries. The tourniquet increases the risk of sepsis. Tourniquet release allows metabolites from the leg to enter into the circulation, and also carries a risk of pulmonary thromboembolism. Carbon dioxide is eliminated by spontaneous hyperventilation under regional anaesthesia. If not eliminated by an increase of mechanical ventilation during general anaesthesia, it may raise intracranial pressure in head trauma patients. Various chemotactic and cytolytic agents may cause lung injury. Mobilization of blood volume at tourniquet placement and release may have detrimental haemodynamic effects in patients with coronary or cardiac insufficiency. The tourniquet increases arterial pressure after 20 to 25 minutes under general anaesthesia. Regional anaesthesia is considered as the technique of choice for the prevention of "tourniquet hypertension", closely linked to pain and relievable by local anaesthetics. Tourniquet modifies also the pharmacokinetics of anaesthetic and other agents. It generates hyperthermia, especially in children. Prospective and comparative studies did not show any advantage as far as duration of surgery and amount of blood loss are concerned. In order to minimize its side effects, the tourniquet must be used within the frame of a strict procedure, with a well adapted and regularly checked equipment. Duration of ischaemia should be as short as possible and not continue for more than two hours, with a reperfusion of 15 minutes every hour. Local hypothermia seems to be a safe means for decreasing side effects.

Intravenous regional anesthesia using lidocaine and ketorolac

Nonsteroidal antiinflammatory drugs (NSAIDs) interfere with the synthesis of inflammatory mediators and can supplement postoperative pain relief. We postulated that using the parenterally available NSAID ketorolac (K) as a component of intravenous regional anesthesia (IVRA) would suppress intraoperative tourniquet pain and enhance postoperative analgesia. Sixty patients were assigned randomly and blindly to receive either intravenous (i.v.) saline and IVRA with 0.5% lidocaine, IV K and IVRA 0.5% lidocaine, or i.v. saline and IVRA 0.5% lidocaine with K. The patients who received IVRA K reported significantly less intraoperative tourniquet pain, with lower verbal analog pain scores at 15 and 30 min after tourniquet inflation. Similarly, IVRA-K patients experienced less postoperative pain with lower visual analog scale (VAS) pain scores at 30 and 60 min, and required no fentanyl for control of early postoperative pain in the postanesthesia care unit (PACU). They also required fewer analgesic tablets in the first 24 h (1.9 +/- 1.4 Tylenol No. 3 tablets compared to the other two groups, 4.6 +/- 1.3 and 3.0 +/- 1.1; P < 0.05). We conclude that K improves IVRA with 0.5% lidocaine both in terms of controlling intraoperative tourniquet pain and by diminishing postoperative pain.