Tiirkish Neiirosiirgery 9: 64 - 67, 1999 Cosar: Pain Control Following Liimbar Lamiiiectomy

Pain ControlComparison of

Following LumbarEpidural MorphinePlus Bupivacaine

Laminectomy:and Morphine

Lomber Laminektomi Sonrasi Agri Kontrolü: Epidural Martin ve Martin ArtiBupivakainin Karsilastirilmasi

AHMET COSAR, MEHMET DANEYEMEZ, ERCAN KURT, FERRUH BILGIN, ZAFER ÇANAKÇIFERRUH GEZEN, A. HIKMET SÜER

Department of Neurosurgery (M.D, Z.ç, F.G),Department of Anesthesiology and Reanimation (A.ç, E.K, F.B, A.HS.),Gülhane Military Medical Academy, Medical Faculty, Ankara, Turkey

Abstract: A comparison of the effects of epidural morphineand epidural morphine + bupivacaine on postoperativepain following lumbar laminectomy and discectomy.Thirty American Society of Anesthesiolgists (ASA) ipatients undergoing lumbar laminectomy and discectomywere randomly assigned to two groups (n = IS/group).In each case, after removing the herniated disc, the surgeonplaced an epidural catheter. Then, while in the recoveryroom, patients were asked to assess their pain accordingto a 10 cm Visual Analogue Scale (VAS). Following this,group I received an epidural injection of 2-mg morphine+ 10 ml normal saline, and group II received 2 mgmorphine + 2 ml bupivacaine 0.5% + 8-ml normal salineby the same route. Postoperative analgesia was achievedin most patients, and alternatiye parenteral analgesic drugswere used in those who found the epidural treatmentinsufficient. Side effects were encountered in three groupI patients, the problems being globe vesicale, woundinfection, and difficult micturition. We achievedsatisfactory postoperative analgesia with epiduralmorphine or epidural morphine + bupivacaine in 24 of30 patients who underwent lumbar laminectomy anddiscectomy. Adding bupivacaine to morphine does notenhance the analgesic effect, and there were no significantdifference in quality and duration of analgesia betweenthe morphine and morphine + bupivacaine groups.

Key Words: Bupivacaine, epidural, laminectomy, lumbar,morphine, postoperative analgesia

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Özet: Lomber laminektomi ve diskektomiyi takiben olusanpostoperatif agri üzerine epidural morfin ve morfin +bupivakainin etkileri karsilastirildi. Amerikan AnesteziBirligi (ASA) I grubuna uyan, lomber laminektomi vediskektomi operasyonu geçirecek olan 30 hasta rasgeleseçimle iki gruba (n=15/ grup) ayrildilar. Hernie olan diskçikarhldiktan sonra, hastalara cerrah tarafindan direktgörüs altinda epidural kateter yerlestirildi. Derlenmeodasinda hastalardan agrilarini 10cm' lik Visual AnalogueScale (VAS) skalasina göre degerlendirmeleri istendi.Grup I hastalara epidural kateterden 2 mg morfin +10 mlserum fizyolojik verilirken Grup II hastalara 2 mg morfin+ 2 ml %0.5 bupivakain + 8 ml serum fizyolojik verildi.Tedavinin yetersiz kaldigi düsünülen hastalardapostoperatif analjezi alternatif parenteral analjeziklerlesaglandi. Grup l' de üç hastada yan etki gözlendi (globvezikale, yara enfeksiyonu ve idrar yapmada zorluk).Sonuç olarak lomber laminektomi ve diskektomioperasyonu geçiren 30 hastanin 24'ünde epidural yoldanverilen morfin veya morfin + bupivakainle yeterlipostoperatif analjezi saglandi. Morfine eklenenbupivakain analjezik etkide bir artis saglamadi ve morfinile marfin + bupivakain gruplari arasinda analjezi kalitesive süresi açisindan belirgin bir farklilik saptanmadi.

Anahtar Kelimeler: Bupivakain, epidural,laminektomi,lomber,morfin, postoperatif analjezi

Turkish Neiirosurgery 9: 64 - 67, 1999

INTRODUCTION

Uncontrolled postoperative pain decreaseswound healing and increases postoperativemorbidity. Patients who are in pain may experiencedelayed recovery of pulmonary function and are atgreater risk of developing thromboembolism due toimmobility. As well, these patients tend to suffer fromnausea and vomiting. it is also known that systemicvascular resistance, cardiac workload, andmyocardial oxygen consumption all increase dueto cathecholamine discharge (3).

Postoperative analgesia has been extensivelyresearched and various methods have been used toprevent such complications and achieve patientcomfort. some of this work has shown that epiduraladministration of corticosteroids after laminectomydoes not produce effectiye postoperative analgesia,nor does it decrease postoperative morbidity oraccelerate functional recovery (5). In contrast to thesepoor results, another study revealed that infiltratinga wound with bupivacaine diminishes postoperativepain and analgesic needs (6). Althoughdissatisfaction is often expressed, the most commonmethod of providing pain relief after laminectomyhas been parenteral administration of narcotic andnonnarcotic analgesics.

With the discovery of opiate receptors in thebrain and substantia gelatinosa of the spinal cord,new methods of pain prevention -and treatment weredeveloped. We known that very smail dos es ofopiates placed in the extradural space are abIe to crossthe meninges and produce analgesia by acting on thespinal cord (7). Since the extradural space is easilyaccessible during laminectomy, the extradural routehas been used to provide more effective analgesiafollowing this procedure. This method has yieldedbetter results without any serious side effects.

Recent reports have indicated that acombination of low-dose opioid and local anestheticproduces astronger analgesic effect than opioidalone. Hemodynamic stability, rare side effects andrapid recovery are some of the benefits of combinedtherapy (3). In this study, we aimed to compareepidural administration of morphine and morphine+ bupivacaine, focusing on analgesic effectivenessand side effects.

MATERIAL and METHOD

After we received approval of the protocol fromthe Gülhane Mihtary Medical Academy Ethics

Cosar: Paiii Coiilrol Following Lumbar Lamiiieclomy

Committee, 30 American Society of Anesthesiologists(ASA) I patients, aged 21 to 62 years, who werescheduled for elective lumhar laminectomy anddiscectomy consented to participate in the study.ASA II and higher-risk groups, atopic patients, andthose who did not wish to participate in the studywere excluded.

During the preoperative preview, the patientswere informed as to how to use a 10 cm VAS, onwhich O was designated as no pain and 10 as theworst pain imaginable. We premedicated all patientswith lO-mg oral diazepam and O.S-mgintramuscularatropine 1 hour before surgery. Anesthesia wasinduced with sodium pentothal (3-5 mg/kg) plusfentanyl (2 mg/kg), and was maintained withisoflurane in a 50/50 oxygen/ nitrous oxide mixture.Muscle relaxation was achieved with vecuronium

bromide (O.lmg/kg). SpOi' noninvasive arterialblood pressure, and ECG were monitored andrecorded during the surgery and for 48 hourspostoperatively.

Before wound closure, we inserted a Tuohyepidural cannula through the skin approximately4 cm lateral to the wound, and directed it deeplythrough the muscles to within the wound site. Next,we inserted an epidural catheter through the cannulaund er direct vision, and passed it into the epiduralspace until the tip lay about 5 cm caudally above theupper margin of the laminectomy. We then placed asuction drain in the opposite side of the wound.Once the wound was closed, the epidural catheterline was draped over the patient's shoulder andtaped securely to the skin along its entire length. Abacteriostatic micropore filter filled with sterilenormal saline was attached to the free end of the line.

Extradural catheters were not inserted in patientswho were suspected of having developedcerebrospinal fluid (CSF) leaks through dural defectsthat were produced intraoperatively.

Af ter full recovery in the recovery room[(Somnolence score=l) (2)] (Table 1), each patient wasasked to indicate the severity of his or her pain basedon a lO-cm VAS scoring system. Then group I patientsreceived 2 mg morphine sulfate in 10 ml normalsaline, and group II patients received 2 mg morphinesulfate + 10 mg bupivacaine 0.5% in 8 ml normalsali ne all by epidural route. Further assessments ofpain severity were made at 30 minutes and 60minutes postinjection.

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Tiirkis/i Neiirosiirgery 9: 64 - 67, 1999 Cosar: Pain Control Following Liimbar Laminectomy

RESULTS

Score Description

Table i. Somnolence score description:

1 Full orientatian and eooperation2 Reactive to verbal and pain stimuli,

tendeney for somnolenee3 Reaetive to verbal and pain stimuli, speeeh

and orientation deficiency4 Reaetive to pain, nameactive to verbal

stimulus (no verbal reaetion)5 Nameactive to verbal and pain stimuli.

0.8525.27±2.1O

Group iGroup IIp value

Postoperative pain

7.53±0.927.47±1.060.843

30 min. after epiduralinjeetion

2.67±2.163.27±2.960.525

60 min. after epiduralinjection

1.23±0.441.36±0.500.343

Side effects were encountered in three group ipatients. Globe vesicale developed in one individual;however, after urinary catheterization, and since thepatient needed no additional analgesic, the problemresolved completely. Another patient experienceddifficulty with micturition. The third patient haddeveloped signs of inflammation at the catheterplacement site by 24 hours postsurgery. The catheterwas removed immediately and sent for microbiologicalculture; however, the culture was negatiye.

DISCUSSION

Additional dose

requirementinterval (hours)" 5.15±1.86

Ideal postoperative analgesia should providepain relief, but also allow the patient to be alert andmobile. With these needs, the complications due topain and immobility can be prevented. Effectiveanalgesic doses of parenteral opioids do not leavepatients alert or mobile, even if the staff in therecovery room are allowed to give the drugs infractionated, smaIl doses. Instead, large doses areusually given with relatively large time lapses, so thatpatients fluctuate between drowsy analgesic mobilityand painful immobility. Epidural opioids mightallow us to get closer to achieving ideal postoperativeanalgesia after laminectomy and discectomy, sincemany reports in recent years have cited their use inthe relief of trunk and lower limb pain(9).

Table IV. VAS scoring results.

were achieved. There were no significant differencesbetween the two groups with regard to VAS scores,total dose per group, and number of requests foradditional analgesics (p>O.05) (Tabi e III-IV).

Table III. Number of total doses and additional

dose requirement intervals.

Group i Group II p value

Number of doses 2.40±1.35 2.53±1.19 0.792

Group II (n=15)

32.20±12.50 32.20±12.92

76.13±6.8 76.33±9.15

2/13 3/12

Group i (n=15)

Age (years)

Weight (kg)

Gender (F/M)

There were no statistical1y significantdifferences between the two group s with regard todemographic data (p>O.05)(Table 11).No significantchanges were detected in peripheral 02 saturationand hemodynamic parameters throughout the study(p>O.05).When the therapy failed in two patients ingroup i and in 4 individuals in group II, parenteralanalgesic drugs were administered immediately.Pain relief was achieved in all six of these patients.In the other patients, sufficient levels of analgesia

Table II. Patient demographic data.

The analgesic method was consideredineffective when the first dose failed (Le.the patienl' sVAS score did not decrease). In such cases, thecatheter was removed and parenteral analgesicadministration was started immediately. Later, in theward, VAS scoring was repeated at every hour andthe first dose was repeated if the VAS score wasgreater than or equal to 4. Timing for further dosesand the number of repeated doses were recordedover 48 hours postoperatively. At 6 hours followingtheir operation, the patients were mobilized. Theincidences of complications including respiratorydepression, itching, nausea, vomiting, hypertension,difficult micturition, catheter blockage, and catheterdisplacement were recorded. All patients' catheterswere removed at 48 hours postsurgery, and cathetertips were sent to the microbiology department forculture. Results were compared using the Studenl'st-test, and p<O.05 was accepted as confirmation ofstatistical significance.

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Tiirkish Neiiyosiirgery 9: 64 - 67, 1999

This technique is particularly appropriatefollowing lumbar laminectomy because the surgeoncan place the epidural catheter precisely, under directvision and with httle risk of dural puncture andinfection (9). In our study, no microorganisms wereisolated from any of the catheter tips, though onepatient showed signs of inflammation. it has beensuggested that catheter blockage by blood andserous fluid is the most important problem with theepidural technique, and that this could beminimized by flushing the catheter with normalsaline immediately upon insertion (9). Even thoughwe did not flush the catheters, we encountered no

blockage difficulties in our series.

Epidural administration of low-dose localanesthetic agents in cornbination with opioids hasbeen shown to produce a greater and longer-lastingantinociceptive effect. it has been proposed thatopioids may bind better to spinal opioid receptors inthe presence of local anesthetics (4,7,8). One reportsuggests that this, in turn, leads to reduction in drugdosages required, and a lower incidence of sideeffects from opioids or 10cal anesthetic agents. Inaddition, there are the proposed benefits of morestable hemodynamics and improved functionalability (2). In our series we encountered only twonegative side effects, namely globe vesicale anddifficult micturition. We observed no respiratorydepression, itching, urinary retention, nausea­vomiting, hypotension, or tachyphylaxis.

There were no significant differences betweenthe two group s with regard to 30-minutepostinjection VAS scores, intervals between first andsecond dose injections, and number of dosesadministered within 48 hours (p>O.05). Thus, ourresults do not support the suggestion that epiduraladministration of a cornbination of local anesthetic

agents and opioids is more effectiye than epiduralmorphine alone (1). In conclusion, the addition ofbupivacaine does not improve the analgesic effectof epidurally administered morphine. Epidural

Cosar: Paiii Coiitrol Followiiig Liimbar Lamiiiectol1lY

morphine, with or without bupivacaine, providessufficient postoperative analgesia levels in lumbarlaminectomy and diskectomy patients.

Correspondance: Mehmet Daneyemez,GATA Beyin ve Sinir Cerrahisi ABD06018, Etlik, AnkaraPhone: 0-312-30453 12Fax: 0-312-323 29 99

E-mail: mkd@gata.edu.tr

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2. Daley M. D, Sandler A. N, Turner K. E, Vosu H,Slavehenko P. A Comparison of Epidural andIntramuseular Morphine in Patients FollowingCesarean Section. Anesthesiology 72(2): 289-94, 1990.

3. Ferrante F. M, Vadeboneouer T. R. Postoperative PainManagement. 1si Ed. Churehill Livingstone Ine., NewYork, 1993: pp.216 and 316

4. Lanz E, Kehrberger E, Theiss D. Epidural Morphine:A Clinical Double-Blind Study of Dosage. AnaesthAnalg 64: 786-91, 1985

5. Lavyne M. H, Bilsky M. H. Epidural Steroids,postoperative morbidity, and reeovery in patientsundergoing mierosurgieal lumbar diskeetomy. JNeurosurg 77: 90-95, 1992

6. Milligan K. R, Maeaffe A. L, Fogarty D. J, Waiiaee R.G. H, Ramsey P. Intraoperative BupivaeaineDiminishes Pain After Lumbar Diskeetomy. J BoneJoint Surg [Br]7S-B: 769-71,1993

7. Rattan A. K, MeDonald J. S, Tejwani G. A.Antinocieeptive Interaetions Between Morphine andBupivaeaine Given Epiduraiiy. Anesthesiology 75:A760,1991

8. Shapiro L, Hoffman S, Jedeikin R, Kaplan R. Single­Injeetion Epidural Anaesthesia with Bupivaeaine andMorphine for Prostateetomy. Anaesth Analg 60: 818­20, 1981

9. Teddy P. J, Adams C. B.T, Briggs M, Jamous M. A, KerrJ. H. Extradural Diamorphine in the Control of PainFoiiowing Lumbar Diskeetomy. Journal of Neurology,Neurosurgery, and Psychiatry 44: 1074-78,1981

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