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361 DOES THE PRESENCE OF ACCESORY OBTURATOR NERVE EFFECT THE SUCCESS OF OBTURATOR NERVE BLOCKADE?
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European Journal of Pain 2006, Vol 10 (suppl S1)
358 ROLE OF NORADRENALINE-CONTAINING NEURONS OF THE LOCUS COERULEUS IN BRADYKININ-INDUCED ANTINOCICEPTION ON TRIGEMINAL SENSORY NUCLEUS L.B. Couto2,3 , C.M.R. Ferreira1 , D.H. Elias-Filho1 , C.A. Parada1 , I.R. Pel´a2 , N.C. Coimbra1 ° . 1 Laboratory of Neuroanatomy & Neuropsychobiology, Department of Pharmacology, School of Medicine of Ribeir˜ao Preto of the University of S˜ao Paulo-USP, Ribeir˜ao Preto (SP), Ribeir˜ao Preto (SP), 2 Laboratory of Pharmacology, School of Pharmaceutical Sciences of Ribeir˜ao Preto; University of S˜ao Paulo, Ribeir˜ao Preto (SP), 3 Medicine and Odontology Course, University of Ribeir˜ao Preto (UNAERP), Ribeir˜ao Preto (SP), Brazil The aim of the present study was to investigate the neuromorphological and pharmacological basis of the antinociceptive effect of microinjections of bradykinin into the principal sensory trigeminal nucleus (PSTN) before and after the specific neurochemical damage of locus coeruleus noradrenergic neurons. The present study was carried out in Wistar rats, using the jaw-opening reflex (JOR) and dental pulp stimulation experimental painful model. The rodents were submitted to a stereotaxic surgery for introducing a micropipette in the locus coeruleus and in the PSTN. After the JOR baseline recording, bradykinin or liquor was microinjected in the PSTN in sham-operated group and after the selective noradrenalinecontaining neurons damage with DSP4 solution. The neural hodology between endogenous pain inhibitory system and trigeminal nuclei was also studied in different groups of Wistar rats. The neuroanatomical study showed evidence for reciprocal neuronal pathways connecting the locus coeruleus (LC) to trigeminal sensory nuclei and linking serotonin- and noradrenaline-containing nuclei of the pain inhibitory system to spinal trigeminal nucleus (STN). Microinjections of bradykinin in the PSTN caused a statistically significant long-lasting antinociception, antagonized by the damage of locus coeruleus-noradrenergic neurons with DSP4. These data suggest that serotonin/noradrenalin nuclei of the endogenous pain inhibitory system exert a key-role in the antinociceptive mechanisms of bradykinin, and the locus coeruleus, specifically, is crucially involved in this antinociceptive bradykinin-induced effect. Noradrenergic neurons of the locus coeruleus are critically involved in the antinociceptive effect of bradykinin on PSTN cells. This work was supported by CNPq, FAPESP and FAEPA.
359 POSSIBILITY OF DENTINAL PAIN CONTROL BY THE APPLICATION OF DENTINE ADHESIVES M. Kukletova1 ° , M. Kukleta2 , E. Gojisova3 , Z. Halackova1 . 1 Stomatological Clinic, Medical Faculty, Masaryk University, Brno, 2 Department of Physiology, Medical Faculty, Masaryk University, Brno, 3 Stomatological Clinic, 3rd Medical Faculty Charles University, Prague, Czech Republic Introduction: The major role in pain generation in dentine is attributed to fluid movements within the dentine tubules. The aim of the study was to investigate whether the application of adhesive material on the sensitive tooth can change its pain perception. Material: Twelve adult patients complaining of tooth hypersensitivity participated in the study. In dental office, the hypersensitivity was tested by air drying immediately after, and a week after the adhesives application. Dentine adhesives Single bond was applied on the sensitive surface of the tooth by the standard procedure. Teeth extracted for orthodontic reasons were used for investigating the ability of the same adhesives to obturate dentinal tubules. Scanning and transmission electron microscopy techniques were used for this purpose. Results: In all the patients (20 hypersensitive teeth), the adhesives completely suppressed the efficacy of drying to induce pain in testing, which followed immediately its application. In the control testing performed 1 week later, the complete suppression of pain response was observed in 80% of cases, and significant reduction of the response in 10% of cases. Morphological investigation proved a good connection between dentine and adhesive material in the form of hybride layer. Adhesive material was
Abstracts, 5th EFIC Congress, Free Presentations also found in dentinal tubules, which were completely obturated in all observed cases. Conclusion: The presented results encourage a more extensive study of applying dentinal adhesives in the treatment for dentinal pain. The study was supported by IGA grant No 8055−3 from the Czech Ministry of Health.
360 RELATIONSHIP BETWEEN THE MAGNITUDE OF DIFFUSE NOXIOUS INHIBITORY CONTROL AND TEST STIMULUS INTENSITY IN HUMANS Y. Oono1 ° , K. Fujii2 , K. Motohashi1 , M. Umino1 . 1 Anesthesiology and Clinical Physiology, Department of Oral Restitution, Division of Oral Health Sciences, Graduate School, Tokyo Medical and Dental University, Tokyo, 2 Tsurumi University, Kanagawa, Japan Backgrounds and Aims: Diffuse noxious inhibitory control (DNIC) is a phenomenon in which the effect of noxious stimuli is inhibited by heterotopic noxious stimulation. We previously showed that laser stimulation of the hand decreased the late component of somatosensory evoked potentials (SEPs) induced by electrical tooth stimulation and pain intensity in humans, indicating triggering of DNIC. The purpose of this study was to investigate modulation of the DNIC effect by different test stimulus intensities under constant conditioning stimuli. Methods: The study was approved by the ethics committee of Tokyo Medical and Dental University and adhered to the Declaration of Helsinki. The noxious test stimuli consisted of electrical tooth stimulation at three different intensities applied in randomized order to the upper right central incisor of volunteers. The SEPs were recorded at Cz and summed and averaged for the 32 stimuli at each stimulus intensity. A visual analogue scale (VAS) was used to estimate dental pain intensity. A CO2 laser applied to the right hand was used as the noxious conditioning stimulus. The late component of the SEP (latencies between 150 and 300 ms) and VAS were analyzed. Results: The SEP amplitude and VAS values significantly decreased during the conditioning stimuli, but there were no significant differences in their rates of reduction among the three test stimulus intensities. Conclusions: The results suggested that the DNIC effect does not depend on the intensity of the test stimuli. B30 OTHER 361 DOES THE PRESENCE OF ACCESORY OBTURATOR NERVE EFFECT THE SUCCESS OF OBTURATOR NERVE BLOCKADE? T. Akkaya1 ° , A. Comert2 , S. Kendir2 , H.I. Acar2 , H. Gumus1 , I. Tekdemir2 , A. Elhan2 . 1 Department of Anaesthesia & Pain Unit, Ankara Diskapi Training and Research Hospital, Ankara, 2 Department of Anatomy, School of Medicine, Ankara University, Ankara-Turkey Background and Aims: We investigated the appereance and the incidence of the accessory obturator nerve and its effect on the efficacy of the obturator nerve blockade with classical approach. Methods: This study is carried on 24 sides of twelve cadavers fixed with 10% formaldehyde. Obturator nerve was seperated from lombar plexus to the end. We observed the appereance and the trace of the accessory obturator nerve. We noted the distance of the accessory obturator nerve to the tuberculum pubicum (A), femoral artery (B), upper wall of external opening of canalis obturatorius (C), and median plane (D). We also demonstrated classic nerve blockade at the cadavers. We evaluated the position of the accessory obturator nerve to the needle and the other landmarks. Results: We observed 3 accessory obturator nerves in 24 cadavers. One female had bilateral, and a male had unilateral accessory obturator nerve. The mean distances of the female and male cadavers were A. 4.04 cm B. 1.57 cm C. 2.02 cm
Topic C: DISEASE ENTITIES (HUMAN) D. 4.84 cm consequently. When the last needle position was assessed, we found that the trace of the accessory obturator nerve was different than the obturator nerve. Conclusions: We found that the incidence of the accessory obturator nerve was 12.5%. In the literature this range was reported between 10% and 30%. The incidence of the accessory obturator nerve might decrease the clinical efficacy and success of the incidence of the obturator nerve block. Therefore, blockade of accessory obturator nerve and the obturator nerve should be planned concomitantly.
362 THE EFFECT OF (HUMLUS LUPULUS) HOPS EXTRACT ON TONIC PAIN IN MICE S.H. Hejazian ° , M.H. Dashti, S.M. Mahdavi. Dept of Physiology, Shahid Sadoughi Medical University, Iran Pain is a universal experience which every body will interfere throughout life. There is too much research in botanical materials as potential pain relieving by different ways. A herbal medicine which is introduced as pain reliving drug in Iranian traditional is (humlus lupulus) Hops in this study we conducted to asses the analgesic effect of hops extracts on tonic pain in mice. Material and Methods: This experimental study carried out on 14 adult male Syrian mice which were divided in 2 groups of control (1 ml/kg saline) and test (8 mg/kg Hops extract) injection were done intro perithonialy 15 min before subcutaneous injection of 2% formalin in the left hind paw as a pain inducing agents. Pain rating was carried out during one hour past formalin injection and pain score were calculated for each 5 min intervals. Results: Result of this investigation show that hops has no effect on early response of pain but is effective in late phase of formalin induced pain especially during 20−35 min past formalin injection. Conclusions: Our findings support traditional literatures indicating analgesic effect for hops. Since one of the hops extract components is estrogenic compounds and it has been suggested that estrogen has some analgesic effect the overall pain reliving effect of hops extracts also may be due to this components which need more investigations.
363 REVASCULARIZATION FOLLOWING THE PERIPHERAL ALCOHOL BLOCK K. Serada ° . Department of Anesthesia, Showa University Northern Yokohama Hospital, Yokohama, Japan Background and Aims: The aim of this study to investigate the vascular impairment affecting the peripheral nerve following alcohol block. Methods: 10 rabbits were sacrificed for this study. 0.1 ml of alcohol was injected topically to the sciatic nerve of the rabbits. Microangiography using 25% barium sulfate was performed immediately after these blocks and 2, 4 days 1, 2, 4, 6 weeks later. After removal these nerves, vascular changes were observed by Spalteholz’s preparations. Histologic section stained by hematoxylin and eosin were also studied and compared with angiographic findings. Results: On angiography immediately after block showed avascular formation. One week later, the inflow of the blood vessel was seen from the surrounding tissue of the nerves. The most remarkable neural degeneration in histologic findings was seen after two weeks. Conclusion: We concluded that the restoration of the nerve tissue started from revascularization from the surrounding tissue.
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Topic C: DISEASE ENTITIES (HUMAN) C01 AMPUTATION PAIN 364 PERIOPERATIVE ANALGESIA DECREASES PHANTOM LIMB PAIN FREQUENCY AND INTENSITY AFTER AMPUTATION. A PROSPECTIVE, RANDOMIZED, DOUBLE-BLIND CLINICAL TRIAL D. Aretha1 ° , M. Karanikolas1 , G. Monantera1 , I. Tsolakis2 , S. Papadoulas2 , R.A. Swarm3 , K.S. Filos1 . 1 Anesthesiology and Critical Care, University of Patras, Patras, Achaia; 2 Department of Surgery, University of Patras, Patras, Achaia, Greece, 3 Department of Anesthesiology, Washington University School of Medicine, St Louis, MO, USA Background: Phantom pain is common, difficult to treat, and few controlled treatment studies exist. Phantom pain frequency and intensity were the endpoints of the study. Methods: 38 patients were assigned to one of 5 groups (Table 1). A lumbar epidural catheter was inserted 48 hours preamputation in groups 1–4 (continuous epidural or IV PCA analgesia). Group 5 was the control group. VAS and McGill PRI(R) scores were recorded 48 and 24 hours before, 4 and 10 days, 1 and 6 months after amputation. Anesthesia and analgesia protocol by group Group
Preoperative analgesia
Anesthesia
Postoperative analgesia
1 2 3 4 5
Epi PCA PCA PCA IM Me, po AC
Epi Epi Epi GA GA
Epi Epi PCA PCA IM Me, po AC
(n = 8) (n = 8) (n = 7) (n = 8) (n = 7)
Epi = Epidural, GA = General Anesthesia, AC = Acetaminophen/Codeine tbs, Me = Meperidine. Epidural anesthesia: Bupivacaine 0.5% 10–15 ml + Fentanyl 100–200 mcg. Epidural analgesia: Bupivacaine 0.25% + Fentanyl 2 mcg/ml, 5–10 ml/h. PCA: IV Fentanyl 25–50 mcg, lockout 10 minutes. Doses titrated to VAS < 3.
Results: 33 of 38 patients completed 6 months follow-up. The mean duration of analgesia was 46.5 hours before and 47.2 hours after amputation. Data were analyzed with Kruskal-Wallis test. Pain scores were lower in patients receiving rigorous analgesia vs. controls (Fig). This benefit is pronounced in groups 1 and 2. At 6 months 0 of 8 patients (group 1) and 1 of 8 (group 2) had phantom pain, compared to 5 of 7 in the control group (p < 0.013).
Conclusion: Optimized perioperative analgesia decreases phantom pain after limb amputation.
European Journal of Pain 2006, Vol 10 (suppl S1)
358 ROLE OF NORADRENALINE-CONTAINING NEURONS OF THE LOCUS COERULEUS IN BRADYKININ-INDUCED ANTINOCICEPTION ON TRIGEMINAL SENSORY NUCLEUS L.B. Couto2,3 , C.M.R. Ferreira1 , D.H. Elias-Filho1 , C.A. Parada1 , I.R. Pel´a2 , N.C. Coimbra1 ° . 1 Laboratory of Neuroanatomy & Neuropsychobiology, Department of Pharmacology, School of Medicine of Ribeir˜ao Preto of the University of S˜ao Paulo-USP, Ribeir˜ao Preto (SP), Ribeir˜ao Preto (SP), 2 Laboratory of Pharmacology, School of Pharmaceutical Sciences of Ribeir˜ao Preto; University of S˜ao Paulo, Ribeir˜ao Preto (SP), 3 Medicine and Odontology Course, University of Ribeir˜ao Preto (UNAERP), Ribeir˜ao Preto (SP), Brazil The aim of the present study was to investigate the neuromorphological and pharmacological basis of the antinociceptive effect of microinjections of bradykinin into the principal sensory trigeminal nucleus (PSTN) before and after the specific neurochemical damage of locus coeruleus noradrenergic neurons. The present study was carried out in Wistar rats, using the jaw-opening reflex (JOR) and dental pulp stimulation experimental painful model. The rodents were submitted to a stereotaxic surgery for introducing a micropipette in the locus coeruleus and in the PSTN. After the JOR baseline recording, bradykinin or liquor was microinjected in the PSTN in sham-operated group and after the selective noradrenalinecontaining neurons damage with DSP4 solution. The neural hodology between endogenous pain inhibitory system and trigeminal nuclei was also studied in different groups of Wistar rats. The neuroanatomical study showed evidence for reciprocal neuronal pathways connecting the locus coeruleus (LC) to trigeminal sensory nuclei and linking serotonin- and noradrenaline-containing nuclei of the pain inhibitory system to spinal trigeminal nucleus (STN). Microinjections of bradykinin in the PSTN caused a statistically significant long-lasting antinociception, antagonized by the damage of locus coeruleus-noradrenergic neurons with DSP4. These data suggest that serotonin/noradrenalin nuclei of the endogenous pain inhibitory system exert a key-role in the antinociceptive mechanisms of bradykinin, and the locus coeruleus, specifically, is crucially involved in this antinociceptive bradykinin-induced effect. Noradrenergic neurons of the locus coeruleus are critically involved in the antinociceptive effect of bradykinin on PSTN cells. This work was supported by CNPq, FAPESP and FAEPA.
359 POSSIBILITY OF DENTINAL PAIN CONTROL BY THE APPLICATION OF DENTINE ADHESIVES M. Kukletova1 ° , M. Kukleta2 , E. Gojisova3 , Z. Halackova1 . 1 Stomatological Clinic, Medical Faculty, Masaryk University, Brno, 2 Department of Physiology, Medical Faculty, Masaryk University, Brno, 3 Stomatological Clinic, 3rd Medical Faculty Charles University, Prague, Czech Republic Introduction: The major role in pain generation in dentine is attributed to fluid movements within the dentine tubules. The aim of the study was to investigate whether the application of adhesive material on the sensitive tooth can change its pain perception. Material: Twelve adult patients complaining of tooth hypersensitivity participated in the study. In dental office, the hypersensitivity was tested by air drying immediately after, and a week after the adhesives application. Dentine adhesives Single bond was applied on the sensitive surface of the tooth by the standard procedure. Teeth extracted for orthodontic reasons were used for investigating the ability of the same adhesives to obturate dentinal tubules. Scanning and transmission electron microscopy techniques were used for this purpose. Results: In all the patients (20 hypersensitive teeth), the adhesives completely suppressed the efficacy of drying to induce pain in testing, which followed immediately its application. In the control testing performed 1 week later, the complete suppression of pain response was observed in 80% of cases, and significant reduction of the response in 10% of cases. Morphological investigation proved a good connection between dentine and adhesive material in the form of hybride layer. Adhesive material was
Abstracts, 5th EFIC Congress, Free Presentations also found in dentinal tubules, which were completely obturated in all observed cases. Conclusion: The presented results encourage a more extensive study of applying dentinal adhesives in the treatment for dentinal pain. The study was supported by IGA grant No 8055−3 from the Czech Ministry of Health.
360 RELATIONSHIP BETWEEN THE MAGNITUDE OF DIFFUSE NOXIOUS INHIBITORY CONTROL AND TEST STIMULUS INTENSITY IN HUMANS Y. Oono1 ° , K. Fujii2 , K. Motohashi1 , M. Umino1 . 1 Anesthesiology and Clinical Physiology, Department of Oral Restitution, Division of Oral Health Sciences, Graduate School, Tokyo Medical and Dental University, Tokyo, 2 Tsurumi University, Kanagawa, Japan Backgrounds and Aims: Diffuse noxious inhibitory control (DNIC) is a phenomenon in which the effect of noxious stimuli is inhibited by heterotopic noxious stimulation. We previously showed that laser stimulation of the hand decreased the late component of somatosensory evoked potentials (SEPs) induced by electrical tooth stimulation and pain intensity in humans, indicating triggering of DNIC. The purpose of this study was to investigate modulation of the DNIC effect by different test stimulus intensities under constant conditioning stimuli. Methods: The study was approved by the ethics committee of Tokyo Medical and Dental University and adhered to the Declaration of Helsinki. The noxious test stimuli consisted of electrical tooth stimulation at three different intensities applied in randomized order to the upper right central incisor of volunteers. The SEPs were recorded at Cz and summed and averaged for the 32 stimuli at each stimulus intensity. A visual analogue scale (VAS) was used to estimate dental pain intensity. A CO2 laser applied to the right hand was used as the noxious conditioning stimulus. The late component of the SEP (latencies between 150 and 300 ms) and VAS were analyzed. Results: The SEP amplitude and VAS values significantly decreased during the conditioning stimuli, but there were no significant differences in their rates of reduction among the three test stimulus intensities. Conclusions: The results suggested that the DNIC effect does not depend on the intensity of the test stimuli. B30 OTHER 361 DOES THE PRESENCE OF ACCESORY OBTURATOR NERVE EFFECT THE SUCCESS OF OBTURATOR NERVE BLOCKADE? T. Akkaya1 ° , A. Comert2 , S. Kendir2 , H.I. Acar2 , H. Gumus1 , I. Tekdemir2 , A. Elhan2 . 1 Department of Anaesthesia & Pain Unit, Ankara Diskapi Training and Research Hospital, Ankara, 2 Department of Anatomy, School of Medicine, Ankara University, Ankara-Turkey Background and Aims: We investigated the appereance and the incidence of the accessory obturator nerve and its effect on the efficacy of the obturator nerve blockade with classical approach. Methods: This study is carried on 24 sides of twelve cadavers fixed with 10% formaldehyde. Obturator nerve was seperated from lombar plexus to the end. We observed the appereance and the trace of the accessory obturator nerve. We noted the distance of the accessory obturator nerve to the tuberculum pubicum (A), femoral artery (B), upper wall of external opening of canalis obturatorius (C), and median plane (D). We also demonstrated classic nerve blockade at the cadavers. We evaluated the position of the accessory obturator nerve to the needle and the other landmarks. Results: We observed 3 accessory obturator nerves in 24 cadavers. One female had bilateral, and a male had unilateral accessory obturator nerve. The mean distances of the female and male cadavers were A. 4.04 cm B. 1.57 cm C. 2.02 cm
Topic C: DISEASE ENTITIES (HUMAN) D. 4.84 cm consequently. When the last needle position was assessed, we found that the trace of the accessory obturator nerve was different than the obturator nerve. Conclusions: We found that the incidence of the accessory obturator nerve was 12.5%. In the literature this range was reported between 10% and 30%. The incidence of the accessory obturator nerve might decrease the clinical efficacy and success of the incidence of the obturator nerve block. Therefore, blockade of accessory obturator nerve and the obturator nerve should be planned concomitantly.
362 THE EFFECT OF (HUMLUS LUPULUS) HOPS EXTRACT ON TONIC PAIN IN MICE S.H. Hejazian ° , M.H. Dashti, S.M. Mahdavi. Dept of Physiology, Shahid Sadoughi Medical University, Iran Pain is a universal experience which every body will interfere throughout life. There is too much research in botanical materials as potential pain relieving by different ways. A herbal medicine which is introduced as pain reliving drug in Iranian traditional is (humlus lupulus) Hops in this study we conducted to asses the analgesic effect of hops extracts on tonic pain in mice. Material and Methods: This experimental study carried out on 14 adult male Syrian mice which were divided in 2 groups of control (1 ml/kg saline) and test (8 mg/kg Hops extract) injection were done intro perithonialy 15 min before subcutaneous injection of 2% formalin in the left hind paw as a pain inducing agents. Pain rating was carried out during one hour past formalin injection and pain score were calculated for each 5 min intervals. Results: Result of this investigation show that hops has no effect on early response of pain but is effective in late phase of formalin induced pain especially during 20−35 min past formalin injection. Conclusions: Our findings support traditional literatures indicating analgesic effect for hops. Since one of the hops extract components is estrogenic compounds and it has been suggested that estrogen has some analgesic effect the overall pain reliving effect of hops extracts also may be due to this components which need more investigations.
363 REVASCULARIZATION FOLLOWING THE PERIPHERAL ALCOHOL BLOCK K. Serada ° . Department of Anesthesia, Showa University Northern Yokohama Hospital, Yokohama, Japan Background and Aims: The aim of this study to investigate the vascular impairment affecting the peripheral nerve following alcohol block. Methods: 10 rabbits were sacrificed for this study. 0.1 ml of alcohol was injected topically to the sciatic nerve of the rabbits. Microangiography using 25% barium sulfate was performed immediately after these blocks and 2, 4 days 1, 2, 4, 6 weeks later. After removal these nerves, vascular changes were observed by Spalteholz’s preparations. Histologic section stained by hematoxylin and eosin were also studied and compared with angiographic findings. Results: On angiography immediately after block showed avascular formation. One week later, the inflow of the blood vessel was seen from the surrounding tissue of the nerves. The most remarkable neural degeneration in histologic findings was seen after two weeks. Conclusion: We concluded that the restoration of the nerve tissue started from revascularization from the surrounding tissue.
S97
Topic C: DISEASE ENTITIES (HUMAN) C01 AMPUTATION PAIN 364 PERIOPERATIVE ANALGESIA DECREASES PHANTOM LIMB PAIN FREQUENCY AND INTENSITY AFTER AMPUTATION. A PROSPECTIVE, RANDOMIZED, DOUBLE-BLIND CLINICAL TRIAL D. Aretha1 ° , M. Karanikolas1 , G. Monantera1 , I. Tsolakis2 , S. Papadoulas2 , R.A. Swarm3 , K.S. Filos1 . 1 Anesthesiology and Critical Care, University of Patras, Patras, Achaia; 2 Department of Surgery, University of Patras, Patras, Achaia, Greece, 3 Department of Anesthesiology, Washington University School of Medicine, St Louis, MO, USA Background: Phantom pain is common, difficult to treat, and few controlled treatment studies exist. Phantom pain frequency and intensity were the endpoints of the study. Methods: 38 patients were assigned to one of 5 groups (Table 1). A lumbar epidural catheter was inserted 48 hours preamputation in groups 1–4 (continuous epidural or IV PCA analgesia). Group 5 was the control group. VAS and McGill PRI(R) scores were recorded 48 and 24 hours before, 4 and 10 days, 1 and 6 months after amputation. Anesthesia and analgesia protocol by group Group
Preoperative analgesia
Anesthesia
Postoperative analgesia
1 2 3 4 5
Epi PCA PCA PCA IM Me, po AC
Epi Epi Epi GA GA
Epi Epi PCA PCA IM Me, po AC
(n = 8) (n = 8) (n = 7) (n = 8) (n = 7)
Epi = Epidural, GA = General Anesthesia, AC = Acetaminophen/Codeine tbs, Me = Meperidine. Epidural anesthesia: Bupivacaine 0.5% 10–15 ml + Fentanyl 100–200 mcg. Epidural analgesia: Bupivacaine 0.25% + Fentanyl 2 mcg/ml, 5–10 ml/h. PCA: IV Fentanyl 25–50 mcg, lockout 10 minutes. Doses titrated to VAS < 3.
Results: 33 of 38 patients completed 6 months follow-up. The mean duration of analgesia was 46.5 hours before and 47.2 hours after amputation. Data were analyzed with Kruskal-Wallis test. Pain scores were lower in patients receiving rigorous analgesia vs. controls (Fig). This benefit is pronounced in groups 1 and 2. At 6 months 0 of 8 patients (group 1) and 1 of 8 (group 2) had phantom pain, compared to 5 of 7 in the control group (p < 0.013).
Conclusion: Optimized perioperative analgesia decreases phantom pain after limb amputation.