Continuous Low-Dose 3-in-1 Nerve Blockade for Postoperative Pain Relief After Total Knee Replacement Neal D. Edwards,
FCAnaes,
and Eluned M. Wright,
FCAnaes
Department of Anaesthesia, Morriston Hospital, Heol Maes Eglwys, Cwmrhydyceirw, Swansea, Great Britain
We have investigated the value of a 3-in-1 nerve block, followed by a continuous low-dose infusion of bupivacaine into the femoral nerve sheath for postoperative analgesia after total knee replacement. Thirty-seven patients were randomly allocated to either a control group or a study group. The study group had a catheter placed in the ipsilateral femoral nerve sheath. A 3-in-1 nerve block was then performed in the study group with injection of 30 mL of 0.25% bupivacaine through the catheter. This was
T
he technique of 3-in-1 neural blockade was first described by Winnie et al. (1) in 1973 and involves the injection of local anesthetic into the perineural sheath surrounding the femoral nerve to obtain blockade of the femoral nerve, obturator nerve, and the lateral cutaneous nerve of the thigh. It has been shown to be of value for analgesia after open knee surgery (2) and can be extended to provide continuous analgesia by insertion of a catheter into the femoral nerve sheath (3); however, previous studies used doses of bupivacaine approaching or exceeding the maximum recommended dose (4,5). We have investigated the value of a 3-in-1 block achieved with a lower dose of bupivacaine, followed by a continuous low-dose infusion of bupivacaine into the femoral nerve sheath, as a method of pain relief after total knee replacement.
Methods The study was approved by the hospital ethical committee, and written, informed consent was obtained from each patient. All patients undergoing total knee replacement under general anesthesia were considered eligible for the study. Patients with Accepted for publication March 31, 1992. Address correspondence to Dr. Edwards, Department of Anaesthesia, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, Great Britain. Reprints are not available. 81992 by the International Anesthesia Research Society 0003-2999/92/$5.00
followed by a continuous infusion of 0.125% bupivacaine at 6 mL/h. The study group had significantly lower pain scores 4 and 24 h postoperatively (P < 0.01) and required less postoperative opioid analgesic medication ( P < 0.01) than the control group. The authors conclude that a continuous low-dose infusion into the femoral nerve sheath results in better pain relief than conventional intramuscularly administered narcotics after total knee arthroplasty. (Anesth Analg 1992;75:265-7)
severe cardiorespiratory disease or hepatic or renal impairment were excluded. All patients received a standard anesthetic. Premedication was temazepam (20 mg) 1h before induction of anesthesia. Anesthesia was induced with intravenous fentanyl(1 pg/kg), thiopental(3-5 mgkg), and vecuronium (0.1 mg/kg). The trachea was intubated and the lungs ventilated with oxygen, nitrous oxide, and isoflurane. Muscle relaxation was maintained throughout the operation with intermittent bolus doses of intravenous vecuronium. At the end of the procedure, neuromuscular blockade was reversed with intravenous neostigmine (2.5 mg) and glycopyrronium (0.5 mg). Patients were prospectively randomized to one of two groups. The control group received no addition to the standard anesthetic. In the study group, after induction of anesthesia, a catheter was introduced into the ipsilateral femoral nerve sheath. Under aseptic conditions, the sheath was located with a Tuohy needle, with the double loss-of-resistance technique described previously by Khoo and Brown (6). A 16-gauge Portex epidural catheter was then passed through the Tuohy needle and secured with a standard dressing, so that 10 cm remained within the sheath. If on threading the catheter through the Tuohy needle it met with only minimal resistance, then the catheter was assumed to be correctly positioned. Initially, 30 mL of 0.25% bupivacaine was injected into the catheter to obtain a 3-in-1 block. This was immediately followed by an infusion of 0.125% bupivacaine at 6 mL/h, which was then continued Anesth Analg 1992;752&7
265
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REGIONAL ANESTHESIA AND PAIN MANAGEMENT EDWARDS AND WRIGHT CONTINUOUS 3-IN-1 NERVE BLOCK INFUSION FOR POSTOPERATIVE ANALGESIA
Table 1. Clinical Characteristics of 37 Patients Undergoing Total Knee Replacement
Maletfemale Mean age (SD) (yr)
Study group (n = 19)
Control group (n = 18)
7/12 66.9 (8.9)
8/10 65.6 (5.8)
Table 2. Postoperative Pain Scores (0 = no pain; 100 = worst pain imapnable) and Analgesic Requirements in 37 Patients Study group (n = 19) Pain score at 4 h Pain score at 24 h Analgesia required in first 24 h No. of doses Total papaveretum dose (mg)
Control group ( n = 18)
32.9 (5.8)n 25.1 (4.3)”
64.3 (5.2) 55.6 (4.3)
1.32 ( M y 15.5 (C-55)”
3.17 (2-4) 43.0 (20-80)
Data are mean (SEM or range). “Study group < control group; P < 0.01.
into the postoperative period for 24 h. After the operation, in both groups intermittent intramuscular papaveretum (10-20 mg every 4 h) was prescribed to be given on patient request. Postoperative pain was assessed by a 100-mm visual analogue scale, which was completed by the patient at 4 and 24 h after the operation. In addition, the amount of postoperative opiate analgesia received by each patient in the first 24 h was noted. We did not assess loss of sensation in the distribution of the blocked nerves because of the presence of extensive dressings around the knee and thigh. Patient pain scores and analgesic requirements were compared with the Mann-Whitney U-test.
Results Forty-two patients initially participated in the study; 22 entered the study group and 20 the control group. In three patients in the study group, the femoral nerve catheters became dislodged before completion of the 24-h study period, and these patients were withdrawn from the study. Two patients in the control group did not complete the postoperative visual analogue scale, and these patients were also withdrawn, leaving 19 patients in the study group and 18 patients in the control group. There were no significant differences between the groups with respect to age or gender (Table 1). The postoperative visual analogue scale pain scores and analgesic requirements are shown in Table 2. The pain scores of the patients in the study group were significantly lower than that of the patients
ANESTH ANALG 1992;75:265-7
in the control group at both 4 h ( P < 0.01) and 24 h ( P < 0.01). The patients in the study group required fewer doses of opiate analgesia than patients in the control group ( P < 0.01). Six of 19 patients in the study group required no supplementary analgesia.
Discussion Total knee replacement produces severe pain in 60% and moderate pain in 30% of patients (7). There are several methods available for providing postoperative analgesia, including systemic or epidural opiates and epidural local anesthetics. Opiates are associated with side effects, such as nausea, pruritus, and respiratory depression, whereas epidural local anesthetics may cause bilateral motor blockade (7), shivering, and hypotension. The knee joint is innervated primarily by the femoral nerve but also receives branches of the obturator and sciatic nerves. The 3-in-1 technique will block the femoral and obturator nerves and has the advantage of causing no cardiovascular or respiratory side effects. The block is relatively easy to perform compared with other techniques of regional analgesia and does not require any special positioning of the patient. After knee surgery, postoperative pain can be associated with reflex spasm of the quadriceps muscle, causing further pain and impaired muscle function. Abolition of quadriceps muscle spasm by femoral nerve blockade contributes to the effectiveness of the technique. We saw no complications of the block in our patients, although prolonged femoral nerve blockade has been reported, either as a result of intraneural injection (8) or with high doses of local anesthetic (9). Injection of lower concentrations of local anesthetic through a catheter rather than a hypodermic needle, as in this study, should reduce the risks of this occurring. Previous studies using a 3-in-1 block after knee surgery have used larger doses of bupivacaine. In a study of patients undergoing open knee surgery, Dahl et al. (4) found that a 3-in-1 block performed with 2 mgkg of bupivacaine, followed by an infusion of bupivacaine into the femoral nerve sheath at 0.35 mg.kg-’.h-’, resulted in a significant reduction in postoperative pain; however, of 10 patients in the study group, 1 patient had a plasma bupivacaine concentration of 2.1 p g k g 30 min after the start of the infusion. In a recent study of patients undergoing total knee replacement, Misra et a]. (5) combined a 3-in-1 block with a sciatic nerve block, resulting in effective postoperative analgesia; however, the total dose of bupivacaine given to each patient was 3 mgkg, exceeding the manufacturer’s
ANESTH ANALG 1992;75:265-7
REGIONAL ANESTHESIA AND PAIN MANAGEMENT EDWARDS AND WRIGHT CONTINUOUS 3-IN-1 NERVE BLOCK INFUSION FOR POSTOPERATIVE ANALGESIA
maximum recommended dose of 2 mgkg. The peak plasma concentration in one patient reached 2 pg/mL. The reported toxic concentration for bupivacaine is 2 pg/mL, although minor toxic symptoms have been described at an arterial concentration of 1.5-2.0 &mL (10). Although no patient in either of the studies by Dahl et al. (4) or Misra et al. (5) exhibited any clinical signs or symptoms of toxicity, the safety of the technique may be improved if analgesia can be obtained with a lower dose of local anesthetic. In this study, we have used approximately half the dose of bupivacaine that has been used in previous studies, with a bolus dose of 75 mg of bupivacaine followed by an infusion of 0.125% bupivacaine at 6 mL/h. Pain scores were significantly lower compared with control patients at both 4 h and 24 h, as were 24-h opiate requirements. We have thus shown that a continuous low-dose infusion of bupivacaine into the femoral nerve sheath results in better pain relief after total knee replacement than a conventional intramuscular narcotic regimen, with minimal risk for bupivacaine toxicity. The authors thank the Consultant Orthopaedic Surgeons at Morriston Hospital for allowing their patients to participate in the study, and Drs. P. A. Steane and D. Long for their encouragement.
267
References 1. Winnie AP, Ramamurthy S, Durrani Z.The inguinal perivascular technique of lumbar plexus anaesthesia: the 3-in-1 block. Anesth Analg 1973;52:989-96. 2. Tiemey E, Lewis G, Hurtig JB, Johnson D. Femoral nerve block with bupivacaine 0.25% for postoperative analgesia after open knee surgery. Can J Anaesth 1987;34:4558. 3. Rosenblatt RM. Continuous femoral anaesthesia for lower limb extremity surgery. Anesth Analg 1980;59:631-2. 4 Dahl JB, Christiansen JL, Daugaard JJ, Schultz P, Carlsson P. Continuous blockade of the lumbar plexus after knee surgery-postoperative analgesia and bupivacaine concentrations. Anaesthesia 1988;43:1015-8. 5 Misra U, Pridie AK, McClymont C, Bower S. Plasma concentrations of bupivacaine following combined sciatic and femoral 3-in-1 nerve blocks in open knee surgery. Br J Anaesth 1991; 66:310-3. 6. Khoo ST, Brown TCK. Femoral nerve block: the anatomical basis for a single injection technique. Anaesth Intensive Care 1983;11:40-2. 7. Rai P, Knarr D, Vigdodorlt E, Pither C. Comparison of continuous epidural infusion of local anaesthetic and administration of systemic narcotics in the management of pain after total knee replacement. Anesth Analg 1987;66:401-6. 8. Frerk CM. Palsy after femoral nerve block. Anaesthesia 1988; 43:167-8. 9. Madej TH, Ellis FR, Halsall PJ. Prolonged femoral nerve block with 0.5%bupivacaine. Anaesthesia 1988;43:607-8. 10. Reynolds FA. Comparison of the potential toxicity of bupivacaine, lignocaine and mepivacaine during epidural blockade for surgery. Br J Anaesth 1971;43:567-71.
FCAnaes,
and Eluned M. Wright,
FCAnaes
Department of Anaesthesia, Morriston Hospital, Heol Maes Eglwys, Cwmrhydyceirw, Swansea, Great Britain
We have investigated the value of a 3-in-1 nerve block, followed by a continuous low-dose infusion of bupivacaine into the femoral nerve sheath for postoperative analgesia after total knee replacement. Thirty-seven patients were randomly allocated to either a control group or a study group. The study group had a catheter placed in the ipsilateral femoral nerve sheath. A 3-in-1 nerve block was then performed in the study group with injection of 30 mL of 0.25% bupivacaine through the catheter. This was
T
he technique of 3-in-1 neural blockade was first described by Winnie et al. (1) in 1973 and involves the injection of local anesthetic into the perineural sheath surrounding the femoral nerve to obtain blockade of the femoral nerve, obturator nerve, and the lateral cutaneous nerve of the thigh. It has been shown to be of value for analgesia after open knee surgery (2) and can be extended to provide continuous analgesia by insertion of a catheter into the femoral nerve sheath (3); however, previous studies used doses of bupivacaine approaching or exceeding the maximum recommended dose (4,5). We have investigated the value of a 3-in-1 block achieved with a lower dose of bupivacaine, followed by a continuous low-dose infusion of bupivacaine into the femoral nerve sheath, as a method of pain relief after total knee replacement.
Methods The study was approved by the hospital ethical committee, and written, informed consent was obtained from each patient. All patients undergoing total knee replacement under general anesthesia were considered eligible for the study. Patients with Accepted for publication March 31, 1992. Address correspondence to Dr. Edwards, Department of Anaesthesia, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX, Great Britain. Reprints are not available. 81992 by the International Anesthesia Research Society 0003-2999/92/$5.00
followed by a continuous infusion of 0.125% bupivacaine at 6 mL/h. The study group had significantly lower pain scores 4 and 24 h postoperatively (P < 0.01) and required less postoperative opioid analgesic medication ( P < 0.01) than the control group. The authors conclude that a continuous low-dose infusion into the femoral nerve sheath results in better pain relief than conventional intramuscularly administered narcotics after total knee arthroplasty. (Anesth Analg 1992;75:265-7)
severe cardiorespiratory disease or hepatic or renal impairment were excluded. All patients received a standard anesthetic. Premedication was temazepam (20 mg) 1h before induction of anesthesia. Anesthesia was induced with intravenous fentanyl(1 pg/kg), thiopental(3-5 mgkg), and vecuronium (0.1 mg/kg). The trachea was intubated and the lungs ventilated with oxygen, nitrous oxide, and isoflurane. Muscle relaxation was maintained throughout the operation with intermittent bolus doses of intravenous vecuronium. At the end of the procedure, neuromuscular blockade was reversed with intravenous neostigmine (2.5 mg) and glycopyrronium (0.5 mg). Patients were prospectively randomized to one of two groups. The control group received no addition to the standard anesthetic. In the study group, after induction of anesthesia, a catheter was introduced into the ipsilateral femoral nerve sheath. Under aseptic conditions, the sheath was located with a Tuohy needle, with the double loss-of-resistance technique described previously by Khoo and Brown (6). A 16-gauge Portex epidural catheter was then passed through the Tuohy needle and secured with a standard dressing, so that 10 cm remained within the sheath. If on threading the catheter through the Tuohy needle it met with only minimal resistance, then the catheter was assumed to be correctly positioned. Initially, 30 mL of 0.25% bupivacaine was injected into the catheter to obtain a 3-in-1 block. This was immediately followed by an infusion of 0.125% bupivacaine at 6 mL/h, which was then continued Anesth Analg 1992;752&7
265
266
REGIONAL ANESTHESIA AND PAIN MANAGEMENT EDWARDS AND WRIGHT CONTINUOUS 3-IN-1 NERVE BLOCK INFUSION FOR POSTOPERATIVE ANALGESIA
Table 1. Clinical Characteristics of 37 Patients Undergoing Total Knee Replacement
Maletfemale Mean age (SD) (yr)
Study group (n = 19)
Control group (n = 18)
7/12 66.9 (8.9)
8/10 65.6 (5.8)
Table 2. Postoperative Pain Scores (0 = no pain; 100 = worst pain imapnable) and Analgesic Requirements in 37 Patients Study group (n = 19) Pain score at 4 h Pain score at 24 h Analgesia required in first 24 h No. of doses Total papaveretum dose (mg)
Control group ( n = 18)
32.9 (5.8)n 25.1 (4.3)”
64.3 (5.2) 55.6 (4.3)
1.32 ( M y 15.5 (C-55)”
3.17 (2-4) 43.0 (20-80)
Data are mean (SEM or range). “Study group < control group; P < 0.01.
into the postoperative period for 24 h. After the operation, in both groups intermittent intramuscular papaveretum (10-20 mg every 4 h) was prescribed to be given on patient request. Postoperative pain was assessed by a 100-mm visual analogue scale, which was completed by the patient at 4 and 24 h after the operation. In addition, the amount of postoperative opiate analgesia received by each patient in the first 24 h was noted. We did not assess loss of sensation in the distribution of the blocked nerves because of the presence of extensive dressings around the knee and thigh. Patient pain scores and analgesic requirements were compared with the Mann-Whitney U-test.
Results Forty-two patients initially participated in the study; 22 entered the study group and 20 the control group. In three patients in the study group, the femoral nerve catheters became dislodged before completion of the 24-h study period, and these patients were withdrawn from the study. Two patients in the control group did not complete the postoperative visual analogue scale, and these patients were also withdrawn, leaving 19 patients in the study group and 18 patients in the control group. There were no significant differences between the groups with respect to age or gender (Table 1). The postoperative visual analogue scale pain scores and analgesic requirements are shown in Table 2. The pain scores of the patients in the study group were significantly lower than that of the patients
ANESTH ANALG 1992;75:265-7
in the control group at both 4 h ( P < 0.01) and 24 h ( P < 0.01). The patients in the study group required fewer doses of opiate analgesia than patients in the control group ( P < 0.01). Six of 19 patients in the study group required no supplementary analgesia.
Discussion Total knee replacement produces severe pain in 60% and moderate pain in 30% of patients (7). There are several methods available for providing postoperative analgesia, including systemic or epidural opiates and epidural local anesthetics. Opiates are associated with side effects, such as nausea, pruritus, and respiratory depression, whereas epidural local anesthetics may cause bilateral motor blockade (7), shivering, and hypotension. The knee joint is innervated primarily by the femoral nerve but also receives branches of the obturator and sciatic nerves. The 3-in-1 technique will block the femoral and obturator nerves and has the advantage of causing no cardiovascular or respiratory side effects. The block is relatively easy to perform compared with other techniques of regional analgesia and does not require any special positioning of the patient. After knee surgery, postoperative pain can be associated with reflex spasm of the quadriceps muscle, causing further pain and impaired muscle function. Abolition of quadriceps muscle spasm by femoral nerve blockade contributes to the effectiveness of the technique. We saw no complications of the block in our patients, although prolonged femoral nerve blockade has been reported, either as a result of intraneural injection (8) or with high doses of local anesthetic (9). Injection of lower concentrations of local anesthetic through a catheter rather than a hypodermic needle, as in this study, should reduce the risks of this occurring. Previous studies using a 3-in-1 block after knee surgery have used larger doses of bupivacaine. In a study of patients undergoing open knee surgery, Dahl et al. (4) found that a 3-in-1 block performed with 2 mgkg of bupivacaine, followed by an infusion of bupivacaine into the femoral nerve sheath at 0.35 mg.kg-’.h-’, resulted in a significant reduction in postoperative pain; however, of 10 patients in the study group, 1 patient had a plasma bupivacaine concentration of 2.1 p g k g 30 min after the start of the infusion. In a recent study of patients undergoing total knee replacement, Misra et a]. (5) combined a 3-in-1 block with a sciatic nerve block, resulting in effective postoperative analgesia; however, the total dose of bupivacaine given to each patient was 3 mgkg, exceeding the manufacturer’s
ANESTH ANALG 1992;75:265-7
REGIONAL ANESTHESIA AND PAIN MANAGEMENT EDWARDS AND WRIGHT CONTINUOUS 3-IN-1 NERVE BLOCK INFUSION FOR POSTOPERATIVE ANALGESIA
maximum recommended dose of 2 mgkg. The peak plasma concentration in one patient reached 2 pg/mL. The reported toxic concentration for bupivacaine is 2 pg/mL, although minor toxic symptoms have been described at an arterial concentration of 1.5-2.0 &mL (10). Although no patient in either of the studies by Dahl et al. (4) or Misra et al. (5) exhibited any clinical signs or symptoms of toxicity, the safety of the technique may be improved if analgesia can be obtained with a lower dose of local anesthetic. In this study, we have used approximately half the dose of bupivacaine that has been used in previous studies, with a bolus dose of 75 mg of bupivacaine followed by an infusion of 0.125% bupivacaine at 6 mL/h. Pain scores were significantly lower compared with control patients at both 4 h and 24 h, as were 24-h opiate requirements. We have thus shown that a continuous low-dose infusion of bupivacaine into the femoral nerve sheath results in better pain relief after total knee replacement than a conventional intramuscular narcotic regimen, with minimal risk for bupivacaine toxicity. The authors thank the Consultant Orthopaedic Surgeons at Morriston Hospital for allowing their patients to participate in the study, and Drs. P. A. Steane and D. Long for their encouragement.
267
References 1. Winnie AP, Ramamurthy S, Durrani Z.The inguinal perivascular technique of lumbar plexus anaesthesia: the 3-in-1 block. Anesth Analg 1973;52:989-96. 2. Tiemey E, Lewis G, Hurtig JB, Johnson D. Femoral nerve block with bupivacaine 0.25% for postoperative analgesia after open knee surgery. Can J Anaesth 1987;34:4558. 3. Rosenblatt RM. Continuous femoral anaesthesia for lower limb extremity surgery. Anesth Analg 1980;59:631-2. 4 Dahl JB, Christiansen JL, Daugaard JJ, Schultz P, Carlsson P. Continuous blockade of the lumbar plexus after knee surgery-postoperative analgesia and bupivacaine concentrations. Anaesthesia 1988;43:1015-8. 5 Misra U, Pridie AK, McClymont C, Bower S. Plasma concentrations of bupivacaine following combined sciatic and femoral 3-in-1 nerve blocks in open knee surgery. Br J Anaesth 1991; 66:310-3. 6. Khoo ST, Brown TCK. Femoral nerve block: the anatomical basis for a single injection technique. Anaesth Intensive Care 1983;11:40-2. 7. Rai P, Knarr D, Vigdodorlt E, Pither C. Comparison of continuous epidural infusion of local anaesthetic and administration of systemic narcotics in the management of pain after total knee replacement. Anesth Analg 1987;66:401-6. 8. Frerk CM. Palsy after femoral nerve block. Anaesthesia 1988; 43:167-8. 9. Madej TH, Ellis FR, Halsall PJ. Prolonged femoral nerve block with 0.5%bupivacaine. Anaesthesia 1988;43:607-8. 10. Reynolds FA. Comparison of the potential toxicity of bupivacaine, lignocaine and mepivacaine during epidural blockade for surgery. Br J Anaesth 1971;43:567-71.
