British Journal of Anaesthesia 1990; 65: 537-539
EFFECT OF ADRENALINE ON PLASMA CONCENTRATIONS OF BUPIVACAINE FOLLOWING INTRA-ARTICULAR INJECTION OF BUPIVACAINE FOR KNEE ARTHROSCOPY J. F. BUTTERWORTH IV, R. S. CARNES in, M. P. SAMUEL, D. JANEWAY AND G. G. POEHLING
We administered 0.5% bupivacaine 30 ml either with or without adrenaline 5 fig mf~' randomly to 16 healthy outpatients, to determine the efficacy of local and intra-articular local anaesthesia for knee arthroscopy and whether or not adrenaline should be added to intra-articular bupivacaine. Bupivacaine concentrations were measured in plasma obtained 15, 30, 45 and 60 min after intra-articular injection. Patients receiving bupivacaine with adrenaline had significantly smaller plasma concentrations of bupivacaine at all times than did patients receiving plain bupivacaine. The maximal concentrations of bupivacaine in the plain group (median 515 ng ml'1, range 46-875 ng ml'1) were greater than those in the adrenaline group (median 33ngml'', range 7-125 ng ml-1) (? = 0.001). All patients found the anaesthetic satisfactory. We conclude that intra-articulary'local anaesthesia is satisfactory for outpatient arthroscopic surgery, and that adrenaline should probably be added to bupivacaine before intra-articular injection. KEY WORDS Anaesthetics, local: bupivacaine, plasma concentrations. Pharmacokinetics: bupivacaine, intra-articular injection.
Diagnostic arthroscopy of the knee is undertaken usually with general or conduction anaesthesia. During the past 3 years, we have developed an intra-articular local anaesthetic technique for arthroscopy which permits ambulation and early discharge. This report describes both our technique of anaesthesia and the effect of adrenaline on plasma concentrations of bupivacaine following intra-articular injection.
Following review and approval of our study by our Clinical Research Practices Committee, we obtained informed consent from 16 healthy patients of both sexes undergoing outpatient diagnostic arthroscopy of the knee. Patients were allocated randomly to intra-articular injection of 0.5 % bupivacaine either with (n = 9) or without (n = 7) adrenaline 5 ug ml"1. The adrenaline group included six males and three females (median age 46 yr (range 21-84 yr); median weight 75 kg (range 50-105 kg)). The plain group included six males and one female (median age 31 yr (range 27-58 yr); median weight 80 kg (range 49-120 kg)). Following preparation of the skin with povidone-iodine, 1 % lignocaine with adrenaline 5 ug ml"1 was injected s.c. 1-2 cm from the superolateral, inferolateral, and inferomedial margins of the patella using a 25-gauge needle. Using a total of no more than 20 ml (200 mg) of lignocaine, each weal was expanded to achieve cutaneous anaesthesia of the three arthroscopic ports. With the knee flexed approximately 10°, 0.5 % bupivacaine 30 ml was injected slowly (over approximately 3 min) into the joint space through an 18-gauge needle inserted at the superolateral aspect of the patella. Negative aspiration (or, in some cases, aspiration of joint fluid), ease of injection and palpable distension of the joint space JOHN F. BUTTERWORTH rv, M.D., ROBERT S. CARNES HI*, M.D.
(Department of Anesthesia); MICHAEL P. SAMUEL, B.S. (Department of Biochemistry); DAVID JANEWAY, M.D., GARY G.
POEHLING, M.D. (Department of Orthopedic Surgery); Wake Forest University Medical Center, 300 South Hawthorne Road, Winston-Salem, North Carolina 27103, U.S.A. Accepted for Publication: May 3, 1990. •Present address: Department of Anesthesia, Naval Hospital, Portsmouth, Virginia 23708, U.S.A.
Downloaded from http://bja.oxfordjournals.org/ at University of Saskatchewan on July 19, 2015
METHODS AND RESULTS
SUMMARY
BRITISH JOURNAL OF ANAESTHESIA
538
ryuw
_ 500i
1
1
I
j? 400-
1I
8 8 § 300a.
•
Plain
g 200-
•
Adrenaline
last
E Q.
1000-
15
•
•
*
30
45
60
Elapsed time (min)
FIG. 1. Effect of adrenaline on plasma concentrations of bupivacaine following injection into the knee joint (means, SEM). Differences between groups are significant overall (P < 0.002) and at all time points (P < 0.01).
telephone on their response to the anaesthetic. All indicated that diey would request the same anaesthetic if they were to require another arthroscopic procedure. COMMENT
Our intra-articular/field block anaesthetic appears to be simple arid acceptable to patients undergoing outpatient arthroscopy of the knee. As bupivacaine is chosen most often for cutaneous (in addition to intra-articular) injection, we believe that adrenaline should be added to bupivacaine when our technique is used. As the ventilatory response to sedative medication (the fentanyl and midazolam used for most of our patients) is unpredictable, we recommend that arterial oxygen saturation be monitored whenever this technique is used. Previous reports of plasma concentrations of local anaesthetic following intra-articular injections have included a wide variety of dosing regimens [3-6]. However, none has reported bupivacaine concentrations when bupivacaine was used as the primary anaesthetic. Variations in technique may influence systemic absorption of intra-articularly injected local anaesthetics sufficiently to alter the safe range of doses. Nonetheless, both the absolute values and variability of our plasma concentrations of bupivacaine were similar
Downloaded from http://bja.oxfordjournals.org/ at University of Saskatchewan on July 19, 2015
by the local anaesthetic confirmed correct needle placement. Surgery began 25-30 min later. Arthroscopy was performed without a tourniquet using the technique described by McGinty [1]. Any bupivacaine remaining in the joint space was flushed out rapidly by Hartmann's solution injected to distend the joint space. Venous blood samples were collected 15, 30, 45 and 60 min following intra-articular injection. Samples were aspirated into citrated vacuum tubes and cooled immediately in an ice bath. Following centrifugation, the samples were subjected to gas chromatographic/mass spectrographic analysis for measurement of plasma concentrations of bupivacaine. Numerical data are presented as means (SEM) or as medians and ranges. Bupivacaine concentrations were compared using multivariate analysis of variance for repeated measures. Fisher's exact test and Wilcoxon's rank sum test suggested that the two groups were similar in age, weight and height. The anaesthetic was successful in every case. The arthroscopic procedure required a median time of 50 min (range 25-105 min). Patients were sedated with a median dose of fentanyl 100 ug i.v. (range 0-150 ug) and with a median dose of midazolam 3 mg i.v. (range 0-9 nig). The usual indication for sedation was excessive anxiety before operation. Patients who received fentanyl, midazolam or both typically received approximately equal doses before and after the block. Monitoring consisted of ECG (lead II), noninvasive arterial pressure, and finger pulse oximetry. Patients were discharged from our unit following a median 32.5 min recovery time (range 15-85 min). The patients receiving bupivacaine with adrenaline demonstrated significantly {P < 0.002) smaller concentrations of plasma bupivacaine overall, and at all individual time points (P < 0.01 in every case), than patients receiving plain bupivacaine (fig. 1). Moreover, the maximal concentrations of bupivacaine achieved in each patient were less in the adrenaline group (median 33 ng ml"1, range 7-125 ng ml"1) than in the plain group (median 515 ng ml"1, range 46-875 ng ml"1) (P = 0.001). No patient in either group had a bupivacaine concentration greater than 1 ug ml"1, the value at which toxicity has been reported [2]. There were no signs of toxic reactions to local anaesthetic or adrenaline. After operation, all patients were questioned by
INTRA-ARTICULAR ANAESTHESIA FOR ARTHROSCOPY to those reported by Katz and colleagues [6]. In conclusion, we believe that this local anaesthetic technique provides patient satisfaction, with minimal postoperative recovery for patients undergoing diagnostic arthroscopy of the knee. The marked reduction in peak plasma concentrations of bupivacaine produced by the addition of adrenaline may allow safe administration of bupivacaine for cutaneous anaesthesia. REFERENCES
4.
5.
6.
caine at low plasma concentration. Anesthesiology 1984; 61:99-100. Pevey JK. Outpatient arthroscopy of the knee under local anesthesia. American Journal of Sports Medicine 1978; 6: 122-127. Debruyne D, Moulin MA, Cannes C, Beguin JA, Locker B. Monitoring serum bupivacaine levels during arthroscopy. European Journal of Clinical Pharmacology 1985; 27: 733-735. Halperin N, Axer A, Hirschberg E, Agasi M. Arthroscopy of the knee under local anesthesia and controlled pressure irrigation. Clinical Orthopaedics and Related Research 1976;134: 176-179. Katz JA, Kaeding CS, Hill JR, Henthorn TK. The pharmacokinetics of bupivacaine when injected intraarticularly after knee arthroscopy. Anesthesia and Analgesia 1988; 67: 872-875.
Downloaded from http://bja.oxfordjournals.org/ at University of Saskatchewan on July 19, 2015
1. McGinty JB, Matza RA. Arthroscopy of the knee. Journal of Bone and Joint Surgery 1978; 60A: 787-789. 2. Hasselstrem LJ, Mogensen T. Toxic reaction of bupiva-
3.
539
EFFECT OF ADRENALINE ON PLASMA CONCENTRATIONS OF BUPIVACAINE FOLLOWING INTRA-ARTICULAR INJECTION OF BUPIVACAINE FOR KNEE ARTHROSCOPY J. F. BUTTERWORTH IV, R. S. CARNES in, M. P. SAMUEL, D. JANEWAY AND G. G. POEHLING
We administered 0.5% bupivacaine 30 ml either with or without adrenaline 5 fig mf~' randomly to 16 healthy outpatients, to determine the efficacy of local and intra-articular local anaesthesia for knee arthroscopy and whether or not adrenaline should be added to intra-articular bupivacaine. Bupivacaine concentrations were measured in plasma obtained 15, 30, 45 and 60 min after intra-articular injection. Patients receiving bupivacaine with adrenaline had significantly smaller plasma concentrations of bupivacaine at all times than did patients receiving plain bupivacaine. The maximal concentrations of bupivacaine in the plain group (median 515 ng ml'1, range 46-875 ng ml'1) were greater than those in the adrenaline group (median 33ngml'', range 7-125 ng ml-1) (? = 0.001). All patients found the anaesthetic satisfactory. We conclude that intra-articulary'local anaesthesia is satisfactory for outpatient arthroscopic surgery, and that adrenaline should probably be added to bupivacaine before intra-articular injection. KEY WORDS Anaesthetics, local: bupivacaine, plasma concentrations. Pharmacokinetics: bupivacaine, intra-articular injection.
Diagnostic arthroscopy of the knee is undertaken usually with general or conduction anaesthesia. During the past 3 years, we have developed an intra-articular local anaesthetic technique for arthroscopy which permits ambulation and early discharge. This report describes both our technique of anaesthesia and the effect of adrenaline on plasma concentrations of bupivacaine following intra-articular injection.
Following review and approval of our study by our Clinical Research Practices Committee, we obtained informed consent from 16 healthy patients of both sexes undergoing outpatient diagnostic arthroscopy of the knee. Patients were allocated randomly to intra-articular injection of 0.5 % bupivacaine either with (n = 9) or without (n = 7) adrenaline 5 ug ml"1. The adrenaline group included six males and three females (median age 46 yr (range 21-84 yr); median weight 75 kg (range 50-105 kg)). The plain group included six males and one female (median age 31 yr (range 27-58 yr); median weight 80 kg (range 49-120 kg)). Following preparation of the skin with povidone-iodine, 1 % lignocaine with adrenaline 5 ug ml"1 was injected s.c. 1-2 cm from the superolateral, inferolateral, and inferomedial margins of the patella using a 25-gauge needle. Using a total of no more than 20 ml (200 mg) of lignocaine, each weal was expanded to achieve cutaneous anaesthesia of the three arthroscopic ports. With the knee flexed approximately 10°, 0.5 % bupivacaine 30 ml was injected slowly (over approximately 3 min) into the joint space through an 18-gauge needle inserted at the superolateral aspect of the patella. Negative aspiration (or, in some cases, aspiration of joint fluid), ease of injection and palpable distension of the joint space JOHN F. BUTTERWORTH rv, M.D., ROBERT S. CARNES HI*, M.D.
(Department of Anesthesia); MICHAEL P. SAMUEL, B.S. (Department of Biochemistry); DAVID JANEWAY, M.D., GARY G.
POEHLING, M.D. (Department of Orthopedic Surgery); Wake Forest University Medical Center, 300 South Hawthorne Road, Winston-Salem, North Carolina 27103, U.S.A. Accepted for Publication: May 3, 1990. •Present address: Department of Anesthesia, Naval Hospital, Portsmouth, Virginia 23708, U.S.A.
Downloaded from http://bja.oxfordjournals.org/ at University of Saskatchewan on July 19, 2015
METHODS AND RESULTS
SUMMARY
BRITISH JOURNAL OF ANAESTHESIA
538
ryuw
_ 500i
1
1
I
j? 400-
1I
8 8 § 300a.
•
Plain
g 200-
•
Adrenaline
last
E Q.
1000-
15
•
•
*
30
45
60
Elapsed time (min)
FIG. 1. Effect of adrenaline on plasma concentrations of bupivacaine following injection into the knee joint (means, SEM). Differences between groups are significant overall (P < 0.002) and at all time points (P < 0.01).
telephone on their response to the anaesthetic. All indicated that diey would request the same anaesthetic if they were to require another arthroscopic procedure. COMMENT
Our intra-articular/field block anaesthetic appears to be simple arid acceptable to patients undergoing outpatient arthroscopy of the knee. As bupivacaine is chosen most often for cutaneous (in addition to intra-articular) injection, we believe that adrenaline should be added to bupivacaine when our technique is used. As the ventilatory response to sedative medication (the fentanyl and midazolam used for most of our patients) is unpredictable, we recommend that arterial oxygen saturation be monitored whenever this technique is used. Previous reports of plasma concentrations of local anaesthetic following intra-articular injections have included a wide variety of dosing regimens [3-6]. However, none has reported bupivacaine concentrations when bupivacaine was used as the primary anaesthetic. Variations in technique may influence systemic absorption of intra-articularly injected local anaesthetics sufficiently to alter the safe range of doses. Nonetheless, both the absolute values and variability of our plasma concentrations of bupivacaine were similar
Downloaded from http://bja.oxfordjournals.org/ at University of Saskatchewan on July 19, 2015
by the local anaesthetic confirmed correct needle placement. Surgery began 25-30 min later. Arthroscopy was performed without a tourniquet using the technique described by McGinty [1]. Any bupivacaine remaining in the joint space was flushed out rapidly by Hartmann's solution injected to distend the joint space. Venous blood samples were collected 15, 30, 45 and 60 min following intra-articular injection. Samples were aspirated into citrated vacuum tubes and cooled immediately in an ice bath. Following centrifugation, the samples were subjected to gas chromatographic/mass spectrographic analysis for measurement of plasma concentrations of bupivacaine. Numerical data are presented as means (SEM) or as medians and ranges. Bupivacaine concentrations were compared using multivariate analysis of variance for repeated measures. Fisher's exact test and Wilcoxon's rank sum test suggested that the two groups were similar in age, weight and height. The anaesthetic was successful in every case. The arthroscopic procedure required a median time of 50 min (range 25-105 min). Patients were sedated with a median dose of fentanyl 100 ug i.v. (range 0-150 ug) and with a median dose of midazolam 3 mg i.v. (range 0-9 nig). The usual indication for sedation was excessive anxiety before operation. Patients who received fentanyl, midazolam or both typically received approximately equal doses before and after the block. Monitoring consisted of ECG (lead II), noninvasive arterial pressure, and finger pulse oximetry. Patients were discharged from our unit following a median 32.5 min recovery time (range 15-85 min). The patients receiving bupivacaine with adrenaline demonstrated significantly {P < 0.002) smaller concentrations of plasma bupivacaine overall, and at all individual time points (P < 0.01 in every case), than patients receiving plain bupivacaine (fig. 1). Moreover, the maximal concentrations of bupivacaine achieved in each patient were less in the adrenaline group (median 33 ng ml"1, range 7-125 ng ml"1) than in the plain group (median 515 ng ml"1, range 46-875 ng ml"1) (P = 0.001). No patient in either group had a bupivacaine concentration greater than 1 ug ml"1, the value at which toxicity has been reported [2]. There were no signs of toxic reactions to local anaesthetic or adrenaline. After operation, all patients were questioned by
INTRA-ARTICULAR ANAESTHESIA FOR ARTHROSCOPY to those reported by Katz and colleagues [6]. In conclusion, we believe that this local anaesthetic technique provides patient satisfaction, with minimal postoperative recovery for patients undergoing diagnostic arthroscopy of the knee. The marked reduction in peak plasma concentrations of bupivacaine produced by the addition of adrenaline may allow safe administration of bupivacaine for cutaneous anaesthesia. REFERENCES
4.
5.
6.
caine at low plasma concentration. Anesthesiology 1984; 61:99-100. Pevey JK. Outpatient arthroscopy of the knee under local anesthesia. American Journal of Sports Medicine 1978; 6: 122-127. Debruyne D, Moulin MA, Cannes C, Beguin JA, Locker B. Monitoring serum bupivacaine levels during arthroscopy. European Journal of Clinical Pharmacology 1985; 27: 733-735. Halperin N, Axer A, Hirschberg E, Agasi M. Arthroscopy of the knee under local anesthesia and controlled pressure irrigation. Clinical Orthopaedics and Related Research 1976;134: 176-179. Katz JA, Kaeding CS, Hill JR, Henthorn TK. The pharmacokinetics of bupivacaine when injected intraarticularly after knee arthroscopy. Anesthesia and Analgesia 1988; 67: 872-875.
Downloaded from http://bja.oxfordjournals.org/ at University of Saskatchewan on July 19, 2015
1. McGinty JB, Matza RA. Arthroscopy of the knee. Journal of Bone and Joint Surgery 1978; 60A: 787-789. 2. Hasselstrem LJ, Mogensen T. Toxic reaction of bupiva-
3.
539
