A Comparative Study of Spinal Bupivacaine and

[Downloaded free from http://www.indianjpain.org on Wednesday, January 11, 2017, IP: 128.39.43.162]

Original Article

A Comparative Study of Spinal Bupivacaine and Fentanyl Versus Combined Lumbar Plexus and Sciatic Nerve Block in Lower Limb Orthopedic Procedures Sumana Kundu, Maitreyee Mukherjee, Dipasri Bhattacharya Department of Anaesthesiology and Critical Care, R. G. Kar Medical College and Hospital, Kolkata, West Bengal, India

Abstract Context: Spinal anesthesia is a time‑tested method for orthopedic surgeries of the lower limb while peripheral nerve block is a comparatively newer method and still under controversy. Aims: The aim of this study was to compare efficacy of spinal bupivacaine and fentanyl with combined lumbar plexus and sciatic nerve block in lower limb orthopedic procedures. Settings and Design: A randomized single‑blinded prospective study conducted at orthopedic operation theater and perioperative area. Subjects and Methods: Sixty patients were randomly allocated into two groups, Group A received spinal anesthesia with 12.5 mg bupivacaine and 25 µg fentanyl, Group B received lumbar plexus block with 30 ml (0.25%) bupivacaine and sciatic nerve block with 25 ml (0.25%) bupivacaine. In Group B, three patients were converted to general anesthesia due to failure of development of block. In postoperative period, visual analog scale (VAS) score was assessed, and pethidine was used as rescue analgesic. Statistical Analysis Used: IBM SPSS Statistics for Windows, Version 20.0. (Armonk, NY, USA). Results: Faster onset of sensory and motor block was found in Group A. In the intraoperative period, incidence of hypotension and bradycardia was found to be higher in Group A although statistically insignificant. In the postoperative period, the VAS score difference between the two groups was found to be significantly higher in Group B till 6 h postoperative. The total duration of analgesia was significantly higher in Group B (690.00 ± 108.344 min) than in Group A (264.67 ± 25.962 min). The total dose of analgesic required in first 24 h was significantly less in Group B (200.00 ± 57.17 mg) than in Group A (371.67 ± 28.416 mg). Conclusion: Combination of lumbar plexus and sciatic nerve block provided effective unilateral analgesia for a prolonged time into the postoperative period. Key words: Adjuvant, analgesia, combined lumbar plexus and sciatic nerve block, lower limb orthopedic procedures, spinal anesthesia

Introduction Surgeries of the lower limb such as total hip arthroplasty, total knee arthroplasty, and anterior cruciate ligament reconstruction are associated with moderate to severe postoperative pain which can contribute to immobility‑related complications, delay in hospital discharge, and interfere with functional outcome.[1,2] The outcomes of pain management in these patients affect hospital and patient costs, length of hospital stay and time to patient remobilization.[3] Analgesic techniques should aim to provide optimal pain relief while minimizing side effects such as sedation, postoperative nausea and vomiting (PONV), hypotension, and motor block. Regional analgesia can achieve these aims to some extent, leading to improved functional recovery facilitated by more rapid and effective joint rehabilitation.[4] The regional anesthesia Access this article online Quick Response Code:

Website: www.indianjpain.org

DOI: 10.4103/0970-5333.198058

© 2016 Indian Journal of Pain | Published by Wolters Kluwer - Medknow

techniques reduce neuroendocrine stress responses, central sensitization of the nervous system, and muscle spasms which occur in response to pain stimuli.[5] Among the various regional anesthesia techniques in practice, spinal anesthesia has been used extensively for lower limb surgeries. Spinal anesthesia is rapid in onset and simpler to perform than almost all other regional techniques. Such benefits must be weighed against adverse events, such as postdural puncture headache, back pain, voiding difficulties, and rare potential for hematoma or infection.[6] Address for correspondence: Dr. Sumana Kundu, 35, Sarat Chatterjee Road, Howrah, Kolkata ‑ 711 104, West Bengal, India. E‑Mail: [email protected] This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as the author is credited and the new creations are licensed under the identical terms. For reprints contact: [email protected]

How to cite this article: Kundu S, Mukherjee M, Bhattacharya D. A comparative study of spinal bupivacaine and fentanyl versus combined lumbar plexus and sciatic nerve block in lower limb orthopedic procedures. Indian J Pain 2016;30:189-93. 189

[Downloaded free from http://www.indianjpain.org on Wednesday, January 11, 2017, IP: 128.39.43.162] Kundu, et al.: Spinal Versus Lumbar Plexus-Sciatic Nerve Blocks

Spinal anesthesia, with adjuncts, provides postoperative pain relief for 3–4 h. Intravenous opioids are another option for postoperative pain relief. These systemic opioids may produce undesirable side effects such as PONV and respiratory depression. An alternative regional anesthesia technique is peripheral nerve blockade (PNB) of one or more major nerves supplying the lower limb. PNB may provide effective unilateral analgesia for a prolonged period, with a lower incidence of opioid‑related and autonomic side effects, less motor block, and fewer serious neurological complications compared with spinal anesthesia.[7] In contrast to neuraxial analgesia, continuous PNB techniques do appear to provide pain relief superior to systemic opioid analgesia but with a lower incidence of side effects.[8] Advances in nerve localization such as ultrasound imaging and continuous catheter technology have also helped increase interest in PNB for lower limb surgery.[9] To provide anesthesia and analgesia to the entire leg, a combination of a lumbar plexus block and a “high” sciatic nerve block is necessary.[10] We undertook the study to compare spinal anesthesia with adjuvants versus combined lumbar plexus and sciatic nerve block in lower limb orthopedic procedures. A total 60 patients of American Society of Anesthesiology (ASA) I and II, age 15–50 years, body weight 40–70 kg were randomly allocated into two equal groups in a single‑blinded randomized protocol. Group A (n = 30) received spinal anesthesia with 0.5% hyperbaric bupivacaine (2.5 ml) 12.5 mg and 25 µg fentanyl and Group B (n = 30) received lumbar plexus block with 30 ml (0.25%) bupivacaine and sciatic nerve block with 25 ml (0.25%) bupivacaine with the help of peripheral nerve stimulator. We compared: 1. Onset and duration of sensory blockade 2. Onset and duration of motor blockade 3. Time taken for onset of sensory blockade since giving injection 4. Duration and intensity of postoperative analgesia 5. Intra‑ and post‑operative hemodynamic study 6. Time at which rescue analgesic required and dose during first 24 h required in the two groups 7. Side effects/complications (intraoperative, postoperative). Onset of sensory blockade = time at which T6 level block was achieved. Onset of motor blockade = time at which Bromage score of 4 (complete block) was achieved. Duration of analgesia = onset of sensory blockade till the requirement of rescue analgesic. Intensity of postoperative pain was assessed with visual analog scale (VAS) score. Patients were given analgesic when VAS ≥3 cm or on patient demand. Our study ended when the patient required rescue analgesic. 190

Subjects and Methods Definition of population • • •

Patient with physical status ASA‑I, ASA‑II undergoing lower limb orthopedic procedure Age 15–50 years Body weight‑ 40–70 kg.

Inclusion criteria • • • •

Both sex (male/female) Age ‑15–50 years Body weight ‑ 40–70 kg ASA physical status ‑ I and II.

Exclusion criteria • • • • • • • • •

Patient refusal ASA physical status ‑ III or more Spinal deformity Contraindication to regional anesthesia Allergic to local anesthetic Preexisting neurological deficit Diabetes/asthma/obesity/hypertension Pregnancy, lactation Psychiatric illness.

Methods

After approval from the Institutional Ethics Committee, this study was conducted in the perioperative room, orthopedic operation theater, and postanesthesia care unit of our institution, enlisting 60 adult patients admitted for lower limb orthopedic surgeries. Using the GraphPad StatMate 2.0 (GraphPad Software, Inc. 7825 Fay Avenue, Suite 230 La Jolla, CA 92037 USA) for Windows, the sample size was calculated with the help of data from a previous study.[11] A sample size of 25 in each group was found to have a 80% power with a significance level (alpha) of 0.05. Rounding off, the sample size was taken as 30 in each group. 60 patients of ASA 1 and 2, age 15–50 years, body weight 40–70 kg were randomly allocated into two equal groups of 30 each. Patients with physical status 3 or more or those having any spinal deformity, contraindication to regional anesthesia, allergy to local anesthetic, preexisting neurological deficit, pregnancy, lactation, psychiatric illness were excluded from the study. Group A received spinal anesthesia with bupivacaine and fentanyl, Group B received single shot lumbar plexus and sciatic nerve block by peripheral nerve stimulator. Technique of randomization was by computer‑generated randomization. Group allocation was done by sequentially numbered sealed opaque envelope. Single blinding was achieved by blinding the investigator. Figure 1 shows the process of selection and analysis of patients for this study according to the consort guidelines. Informed consent was taken from all the patients and the study was approved by the ethics committee of the institution. A patient information leaflet was provided to each patient and written consent was obtained. Preoperative anesthetic fitness assessment was conducted on each patient. Indian Journal of Pain ¦ September-December 2016 ¦ Vol 30 ¦ Issue 3


All patients were preloaded with 10 ml/kg Ringer’s lactate solution. Routine monitoring in the form of noninvasive intraoperative blood pressure (NIBP), electrocardiogram, and pulse oximetry was instituted on arrival in perioperative room. Both group of patients received anesthesia under a proper aseptic condition. The same anesthesiologist performed spinal anesthesia and lumbar plexus‑sciatic nerve block every time.

analgesic was given when VAS score ≥3 cm or on patient demand. Our study ended when the patient received rescue analgesic. Injection pethidine (50 mg intramuscularly) was used as rescue analgesic.

In Group A, patients received spinal anesthesia with 2.5 ml of bupivacaine (12.5 mg) hyperbaric solution and 25 µg fentanyl at L3–L4 level.

Results

In Group B, all patients received lumbar plexus and sciatic nerve block with insulated 22 gauge stimuplex needle (100 mm) attached to a peripheral nerve stimulator. For the lumbar plexus block, the patient was put in lateral decubitus. The midline (spinous processes), both iliac crests, and posterior‑superior iliac spine were identified and the lumbar plexus was blocked by the posterior approach. The lumbar plexus was identified by eliciting quadriceps muscle contraction at a current setting below 0.5 mA. The sciatic nerve block was undertaken using posterior transgluteal approach, identifying the nerve by contraction of gastrocnemius muscle (foot plantar flexion) and/or tibialis anterior muscle (foot dorsiflexion). 30 ml of bupivacaine 0.25% was used for lumbar plexus component and 25 ml of bupivacaine 0.25% for sciatic component. Intraoperative assessment of NIBP, SPO2, pulse, and heart rate was recorded immediately after anesthesia and thereafter at every 30 min interval. Anesthesiologist unaware of the technique recorded the parameters. Intensity of pain was assessed by VAS score in immediate postoperative period and at 30 min interval till 6 h postoperative and thereafter at 7th, 8th, 12th, 18th, and 24th h postoperative. When the patient was shifted to PACU, one ward nurse unaware of technique of anesthesia assessed VAS score and side effects. Rescue SCREENING (60)

RANDOMISATION (60)

Any complications such as vomiting, local hematoma, and urinary retention were recorded in 1st 24 h period.

A total of sixty patients were selected. Among the thirty patients in Group B, three patients had to be converted to general anesthesia due to failure of development of adequate motor and sensory block even after waiting for 30 min. Therefore, a total of 57 patients completed the study. Both the groups were comparable with respect to demographic data, ASA grade, preoperative hemodynamic status (P > 0.05). The sensory and motor block onset time were significantly less in Group A than Group B with a P 0.05). In the postoperative period, systolic blood pressure, diastolic blood pressure, and pulse rate were significantly higher in Group A from 60 min to 6 h postoperatively. At 7, 8, 12, 18, 24 h postoperative, the hemodynamic monitoring revealed no significant difference between the two groups. The difference in postoperative VAS score was found to be statistically significant, being higher in Group A than in Group B till 6 h postoperative. From 7 h postoperative, the difference in VAS score became statistically insignificant as shown by the results of Table 3. The total duration of analgesia was found to be significantly higher in Group B (690.00 ± 108.34 min) than in Group A (264.67 ± 25.96 min) as is evident from Table 4 and Figure 2. The total dose of analgesic required in the first 24 h postoperatively was found to be significantly higher in Group A (371.67 ± 28.41 mg) than in Group B (200.00 ± 57.17 mg) as is evident from Table 5 and Figure 3. Table 1: Comparison of sensory block onset (min)

GROUP A (30)

GROUP B (30)

Group

SB onset n

ASSESSMENT (30)

ASSESSMENT (27)

ANALYSIS (57)

REPORT PREPARATION (57)

Figure 1: Flow chart as per CONSORT guidelines. Indian Journal of Pain ¦ September-December 2016 ¦ Vol 30 ¦ Issue 3

Mean

SD

SEM

P

A 30 2.63 0.669 0.122 0.001 B 27 18.07 2.165 0.417 SB: Sensory block, SD: Standard deviation, SEM: Standard error of mean

Table 2: Comparison of motor block onset (min) Group

MB onset n

Mean

SD

SEM

P

A 30 7.83 1.440 0.263 0.004 B 27 33.22 4.569 0.879 MB: Motor block, SD: Standard deviation, SEM: Standard error of mean 191


The monitoring for adverse effects revealed more incidence of hypotension (40% vs. 25.9%), bradycardia (16.67% vs. 7.4%), and nausea (30% vs. 11.11%) in Group A than in Group B as shown in Table 6 and Figure 4 although the difference of hemodynamics between the two groups was found to be statistically insignificant. Table 3: Comparison of visual analog scale at 6 and 7 h postoperatively Group

n

Mean

SD

SEM

P

VAS 6

A 30 2.10 0.305 0.056 0.003 B 27 1.41 0.501 0.096 VAS 7 A 30 2.03 0.183 0.033 0.155 B 27 1.85 0.662 0.127 SD: Standard deviation, SEM: Standard error of mean, VAS: Visual analog scale

Table 4: Comparison of total duration of analgesia (min) Group

Duration n

Mean

SD

SEM

A 30 264.67 25.962 4.740 B 27 690.00 108.344 20.851 SD: Standard deviation, SEM: Standard error of mean

P 0.002

Table 5: Comparison of total dose of analgesic required in the first 24 h postoperatively (mg) Group

Total dose n

Mean

SD

SEM

A 30 371.67 28.416 5.188 B 27 200.00 57.177 11.004 SD: Standard deviation, SEM: Standard error of mean

P 0.006

Table 6: Comparison of intraoperative side effects Side effects

Group A, n=30 (%)

Group B, n=27 (%)

Hypotension Bradycardia Nausea Vomiting

12 (40) 5 (16.67) 9 (30) 1 (3.33)

7 (25.92) 2 (7.4) 3 (11.11) 0

800

Discussion Several studies have evaluated the psoas approach in lower limb orthopedic surgeries with sciatic nerve blockade. This study used the combination of sciatic nerve block and lumbar plexus block rather than either technique alone because of the more reliable blockade produced by the complete lumbosacral plexus block. This study showed that performing lumbar plexus‑sciatic nerve block provides effective anesthesia with a few complications in comparison with spinal anesthesia. The study by de Visme, et al. also reported that combined psoas compartment block and sciatic nerve block compared with spinal anesthesia resulted in less hypotension and improved analgesia in elderly patients undergoing hip fracture repair.[11] The duration of analgesia in Group B was longer than in Group A; however, onset of sensory and motor block was significantly later in Group B than in Group A. The comparatively delayed onset of sensory and motor block in patients given lumbar and sciatic nerve block has often raised questions about the efficiency of nerve blocks. The use of a preoperative room with proper monitoring equipment for administering the block will obviate induction time and thus enhance operating room work efficiency. It is supported by the study by Williams et al. who found that regional anesthesia with an induction room was associated with lowest anesthesia‑controlled time.[12] The total analgesic requirement of pethidine was significantly lesser in Group B. This finding is in harmony with the findings of the study by Moreno et al., which reported an excellent and prolonged postoperative analgesia thereby significantly decreasing the need for opioids.[13] The VAS score was found to be significantly lower for a much longer time into the postoperative period in Group B than in Group A. This indicates a better patient well‑being in Group B. Similar findings were found in the study by Luber et al. who found lumbar plexus block appears to have advantages for early postoperative analgesia, leading to increased patient comfort and satisfaction.[14] The median time to first analgesic request for lumbar plexus‑sciatic nerve block group was significantly longer than for spinal anesthesia group. In the study by Horasanli the time

DURATION OF ANALGESIA (min)

MEAN TOTAL ANALGESIC REQUIREMENT (mg) 400

600

300

400

200 100

200

0 0

A

B

Figure 2: Comparison of total duration of analgesia (min).

192

A

B

Figure 3: Comparison of mean total analgesic requirement in the first 24 h postoperatively (mg).

Indian Journal of Pain ¦ September-December 2016 ¦ Vol 30 ¦ Issue 3


Acknowledgment

50

We would like to thank Dr. Arnab K. Koley for help with preparing manuscript.

40 30

Financial support and sponsorship

20 10

Group A

R.G. Kar Medical College and Hospital.

0

Group B

Conflicts of interest

There are no conflicts of interest.

References Figure 4: Comparison of intraoperative side effects.

from block placement until first request for analgesia (the duration of analgesia) was found to be higher in the lumbar plexus‑sciatic nerve block group than in the epidural anesthesia group.[15] A total of sixty patients were selected and randomly allocated into the two groups. While none of the patients in spinal anesthesia group were converted to general anesthesia, 3 patients of the lumbar plexus‑sciatic nerve block group had to be converted to general anesthesia due to failure of development of adequate sensory and motor block even after waiting for 30 min. Thus, the success of providing adequate anesthesia in Group A was 100% while that in Group B was 90%. This study used a neurostimulator‑guided approach for administering the lumbar plexus‑sciatic nerve block. Radiographically assisted needle placement and injection of local anesthetic have the potential to increase success rate of providing adequate anesthesia by the lumbar plexus‑sciatic nerve block approach.[16,17] The study by Auroy et al. reported a high incidence of major complications after posterior lumbar plexus block and occurrence of neurologic complications after the use of a nerve stimulator used for PNB.[18] Complications reported were cardiac arrest, systemic local anesthetic toxicity comprising mainly seizures, transient neurological damages. In the limited sample size of this study, no such complications were reported. A future study with a larger sample size is needed for investigating the incidence of any major complication.

Conclusion The results of this prospective, randomized study demonstrated that a combination of lumbar plexus‑sciatic nerve block using a nerve stimulator provides effective unilateral anesthesia in patients undergoing lower limb orthopedic surgery along with better postoperative analgesia. With the development of modern techniques for nerve localization, it has the potential for providing excellent intraoperative anesthesia and postoperative analgesia resulting in early limb mobilization and rehabilitation of the patient with minimal complications.

Indian Journal of Pain ¦ September-December 2016 ¦ Vol 30 ¦ Issue 3

1. Bonica J, editor. Postoperative pain. In: The Management of Pain. 2nd ed. Philadelphia: Lea & Febiger; 1990. p. 461‑80. 2. Pang WW, Hsu TC, Tung CC, Hung CP, Chang DP, Huang MH. Is total knee replacement more painful than total hip replacement? Acta Anaesthesiol Sin 2000;38:143‑8. 3. Hogan MV, Grant RE, Lee L Jr. Analgesia for total hip and knee arthroplasty: A review of lumbar plexus, femoral, and sciatic nerve blocks. Am J Orthop (Belle Mead NJ) 2009;38:E129‑33. 4. Kehlet H. Surgical stress: The role of pain and analgesia. Br J Anaesth 1989;63:189‑95. 5. Grant CR, Checketts MR. Analgesia for primary hip and knee arthroplasty: The role of regional anaesthesia. Contin Educ Anaesth Crit Care Pain 2008;8:56-61. 6. Mulroy MF, McDonald SB. Regional anesthesia for outpatient surgery. Anesthesiol Clin North America 2003;21:289‑303. 7. Horlocker TT, Kopp SL, Pagnano MW, Hebl JR. Analgesia for total hip and knee arthroplasty: A multimodal pathway featuring peripheral nerve block. J Am Acad Orthop Surg 2006;14:126‑35. 8. Richman JM, Liu SS, Courpas G, Wong R, Rowlingson AJ, McGready J, et al. Does continuous peripheral nerve block provide superior pain control to opioids? A meta‑analysis. Anesth Analg 2006;102:248‑57. 9. Evans H, Steele SM, Nielsen KC, Tucker MS, Klein SM. Peripheral nerve blocks and continuous catheter techniques. Anesthesiol Clin North America 2005;23:141‑62. 10. Chayen D, Nathan H, Chayen M. The psoas compartment block. Anesthesiology 1976;45:95‑9. 11. de Visme V, Picart F, Le Jouan R, Legrand A, Savry C, Morin V. Combined lumbar and sacral plexus block compared with plain bupivacaine spinal anesthesia for hip fractures in the elderly. Reg Anesth Pain Med 2000;25:158‑62. 12. Williams BA, Kentor ML, Williams JP, Figallo CM, Sigl JC, Anders JW, et al. Process analysis in outpatient knee surgery: Effects of regional and general anesthesia on anesthesia‑controlled time. Anesthesiology 2000;93:529‑38. 13. Moreno M, Casalia AG. Peripheral nerve blocks, lumbar plexus anesthesia: Psoas compartment block. Techniques in Regional Anesthesia and Pain Management. Vol. 10. Amsterdam: Elsevier Inc.; 2006. p. 145-9. 14. Luber MJ, Greengrass R, Vail TP. Patient satisfaction and effectiveness of lumbar plexus and sciatic nerve block for total knee arthroplasty. J Arthroplasty 2001;16:17‑21. 15. Horasanli E, Gamli M, Pala Y, Erol M, Sahin F, Dikmen B. A comparison of epidural anesthesia and lumbar plexus-sciatic nerve blocks for knee surgery. Clinics 2010;65:29-34. 16. Chan VW, Nova H, Abbas S, McCartney CJ, Perlas A, Xu DQ. Ultrasound examination and localization of the sciatic nerve: A volunteer study. Anesthesiology 2006;104:309‑14. 17. Karmakar MK, Ho AM, Li X, Kwok WH, Tsang K, Ngan Kee WD. Ultrasound‑guided lumbar plexus block through the acoustic window of the lumbar ultrasound trident. Br J Anaesth 2008;100:533‑7. 18. Auroy Y, Benhamou D, Bargues L, Ecoffey C, Falissard B, Mercier FJ, et al. Major complications of regional anesthesia in France: The SOS regional anesthesia hotline service. Anesthesiology 2002;97:1274‑80.

193