beta-endorphin and Pain--Postoperative

Thoracic surgeries are associated with intense postoperative pain. General opioid analgesia is still the main anaesthetic method. Due to the large number of opioid-induced side effects, alternative methods of pain relief are sought. One of them is the use of balanced analgesia, which consists of regional analgesia, non-opioid painkillers, and small doses of opioids.. The objective of this study was to assess the effectiveness of preoperative thoracic paravertebral block (ThPVB) in the treatment of postoperative pain after video-assisted thoracic surgery (VATS) by measuring hormone levels in blood serum or saliva. It was a randomised, open-label study conducted in a single university hospital setting between May 2018 and September 2019. In total, 119 patients were scheduled for elective video-assisted thoracic surgery. Performed interventions included: preoperative thoracic paravertebral block with 0.5% bupivacaine, followed by postoperative oxycodone combined with nonopioid analgesics. Follow-up period comprised first 24 hours and one, two, and six months after surgery. Main outcomes were measured by pain intensity assessed using the Numerical Rating Scale (NRS) and the levels of the following hormones: testosterone, cortisol, α-amylase activity, sIgA, and β-endorphin.. A total of 119 patients were randomised into two groups and, of these, 49 were subsequently excluded from the analysis. The final analysis included 37 patients from the study group and 33 from the control group. There were no statistically significant differences in the analysed parameters the relative change T1-T0. There was a tendency towards statistical significance in the relative change T2-T0 in testosterone levels. At rest, no statistically significant differences were found between groups and time in the percentage of patients with NRS ≥ 1. During cough, the percentage of patients with NRS ≥ 1 was higher at T1 and T2 time points in the ThPVB group. Of the factors considered, only α-amylase levels statistically significantly increased the chance for higher NRS score after a month [OR = 1.013; 95% PU: 1.001-1.025; p < 0.01].. ThPVB is effective and safe for patients undergoing VATS. It can be an effective alternative for general anaesthesia using high doses of opioids.

Topics: alpha-Amylases; Analgesia; Analgesics, Opioid; beta-Endorphin; Humans; Hydrocortisone; Immunoglobulin A, Secretory; Pain, Postoperative; Testosterone; Thoracic Surgery, Video-Assisted

To observe the effect on supplementary analgesia after total knee arthroplasty (TKA) treated with electroacupunture, and explore it's mechanism.. A total of 40 patients with severe knee osteoarthritis were randomized into an observation group and a control group, 20 cases in each one. During the operation, patients were given epidural anesthesia in the two groups, conventional patient controlled epidural analgesia and oral celecoxib were applied after the operation. In the observation group, electroacupunture was used at Liangqiu (ST 34), Xuehai (SP 10), Yinlingquan (SP 9), Zusanli (ST 36), Fenglong (ST 40) and Qiuxu (GB 40) on the operation side from the 1st to 7th day after the operation to support analgesia, 30 min for each time, once a day. The visual analogue scale (VAS) was used to record postoperative pain of resting state and active state. The levels of serum prostaglandin E. In the observation group, the VAS scores of resting state and active state were superior to the control group on the 3rd, 5th and 7th day after the operaton (all. Electroacupunture has the effect of supplementary analgesia for patients after TKA, the mechanism may be related to promote the synthesis of β-endorphin and inhibit the synthesis of prostaglandin E

Topics: Analgesia, Patient-Controlled; Arthroplasty, Replacement, Knee; beta-Endorphin; Humans; Pain Management; Pain, Postoperative; Prostaglandins

To observe the effectiveness and safety of electroacupuncture (EA) at Neimadian (Extra) and Neiguan (PC 6) for analgesia after thoracic surgery.. One hundred and twenty cases of thoracic surgery were randomly divided into an electroacupuncture (EA) group (60 cases) and a medication group (60 cases). EA was applied at Neimadian (Extra) and Neiguan (PC 6) for postoperation analgesia in the EA group, while patient-controlled intravenous analgesia (PCIA) was applied in the medication group. The score of visual analogue scale (VAS), analgesia effect, safety and beta-endorphin level after the treatment in both groups were compared.. Compared with those before the treatment, the VAS scores in every time point after surgery were decreased (all P < 0.05), which were lower in the EA group (P < 0.01). The excellent and good rates were 96.7% (58/60) and 75.0% (45/60) seperately, the analgesia effect in the EA group (2 h after operation) was superior to that in the medication group (P < 0.01). The safety degree in EA group was higher to that in the medication group (P < 0.01). Compared with that before the treatment, the beta-endorphin level in two groups after treatment was both increased, which was higher in the EA group (P < 0.01).. Electroacupuncture at Neimadian (Extra) and Neiguan (PC 6) has better analgesia effect (2 h after operation) and safety than PICA on analgesia after thoracic surgery.

Topics: Acupuncture Analgesia; Acupuncture Points; Aged; beta-Endorphin; Electroacupuncture; Female; Humans; Male; Middle Aged; Pain, Postoperative; Thoracic Surgery

The purpose of this study was to evaluate the effect of saline washout under the diaphragm on postoperative shoulder tip pain (STP) and β-endorphin (βE) levels in patients who had undergone laparoscopic cholecystectomy (LC).. Between December 2010 and March 2011, 50 patients requiring cholecystectomy for benign gallbladder disease were enrolled in this study. Twenty-five patients (Group 1) underwent LC without saline irrigation, whereas the other 25 were operated on with saline irrigation (30 mL/kg) under the diaphragm (Group 2). Plasma levels of βE were measured before and after the operation. The degree of STP following LC was assessed using a visual analog pain scale (VAS) at 6, 12, and 24 hours postoperatively.. Eight patients in Group 1 (32.0%) and seven patients in Group 2 (28.0%) complained of STP. There was no significant difference between the two groups in operation time, postoperative hospital length, postoperative βE, dose of analgesics, or VAS at 6, 12, and 24 hours after surgery. The intensity of abdominal pain (AP) was significantly higher than that of STP. Significantly elevated levels (11.3±5.1 pg/mL) of βE were observed postoperatively when compared with preoperative levels (9.7±5.2 pg/mL) (P=.02).. Normal saline irrigation under the diaphragm does not reduce postoperative STP after LC. Ancillary techniques to reduce AP and STP should be considered.

Topics: Adult; beta-Endorphin; Cholecystectomy, Laparoscopic; Cholecystitis; Cholelithiasis; Female; Humans; Male; Middle Aged; Pain Measurement; Pain, Postoperative; Pneumoperitoneum, Artificial; Shoulder Pain; Sodium Chloride; Therapeutic Irrigation

Systemic β-endorphin, an endogenous opioid and stress hormone, has been demonstrated to correlate with the postoperative pain intensity, however its putative role as a postoperative pain biomarker has not been cleared.. Thirty patients scheduled for elective hysterectomy were included into the study. Postoperative pain was assessed by a numeric rating scale from 0 to 10. Plasma morphine concentrations were determined using high performance liquid chromatography with UV detection. Plasma β-endorphin concentrations were measured by a radioimmunoassay.. Administration of morphine in intravenous infusion turned out to be a markedly better method of morphine administration up to 4th hour postoperatively regarding both drug concentration and pain rating. A significant correlation between systemic β-endorphin concentration and pain rating at the 4th postoperative hour was found. No association between morphine and β-endorphin concentrations was detected.. Systemic β-endorphin is not an appropriate pain marker in postoperative gynaecologic patients.

Topics: Abdomen; Adult; Analgesics, Opioid; beta-Endorphin; Biomarkers; Drug Monitoring; Elective Surgical Procedures; Female; Humans; Hysterectomy; Infusions, Subcutaneous; Middle Aged; Morphine; Pain, Postoperative; Treatment Outcome

To examine the analgesic effect of preoperative administration of flurbiprofen axetil and that of postoperative administration of a combination of flurbiprofen axetil and fentanyl, as well as perioperative plasma β-endorphin (β-EP) levels in patients undergoing esophagectomy.. Forty-five patients were randomly divided into three groups: group A: 100 mg flurbiprofen axetil preoperative, 10 μg/kg fentanyl + 10 ml placebo postoperative; group B: 100 mg flurbiprofen axetil preoperative, 10 μg/kg fentanyl + 100 mg flurbiprofen axetil postoperative; group C: 10 ml placebo preoperative, 10 μg/kg fentanyl + 10 ml placebo postoperative. Postoperative analgesia was achieved by intravenous infusion containing flurbiprofen axetil and/or fentanyl at 2.0 ml/h (total volume, 100 ml) using infusion pumps. The β-EP was measured at preanesthesia (T(1)), the end of surgery (T(2)), 24 h (T(3)), and 48 h (T(4)) after surgery. Visual analog scale scores (VAS) at T3, T4 (at rest), and rescue analgesic tramadol requirement was recorded.. The VAS of group B was significantly lower than group A and C (P < 0.01) at T(3) and T(4). The β-EP levels at T(2)-T(4) in group A did not differ significantly from those at T(1) (P > 0.05); however, the β-EP levels in group B at T(3)-T(4) increased significantly (P < 0.05), while those in group C increased at T(2) and decreased at T(4) (P < 0.05). The β-EP levels in group B at T(3) and T(4) were the highest as compared to its levels in groups A and C (P < 0.01). Tramadol consumption in group B was significantly lower than in groups A and C (P < 0.01).. These results show that flurbiprofen axetil enhances the analgesic effect of fentanyl associated with increase in β-EP levels.

Topics: Analgesia; Analgesics, Opioid; Anti-Inflammatory Agents, Non-Steroidal; beta-Endorphin; Drug Synergism; Drug Therapy, Combination; Esophageal Neoplasms; Esophagectomy; Female; Fentanyl; Flurbiprofen; Humans; Male; Middle Aged; Pain, Postoperative; Placebos; Preoperative Care

To observe the analgesia effectiveness and safety of electroacupuncture at Neimadian(Extra) for postoperation of abdominal surgery.. One hundred and twenty patients with routine abdominal surgery were randomly divided into an acupuncture group and a medication group, 60 cases in each group. The acupuncture group was treated with electroacupuncture at Neimadian(Extra), which was located on the inside of lower leg, 7 cun above the internal malleolus and 0.5 cun from post edge of tibial. The medication group was treated with patient-controlled intravenous analgesia (PCIA) with Sufentanil. After the treatment, the Visual Analogue Scale (VAS), the security, the analgesic effect and beta-endorphin content were compared.. The postoperative VAS score at 2, 4, 8, 16, 24 and 48 h in the acupuncture group was lower than those in the medication group (all P < 0.05). The analgesic effect at 2, 4, 16 and 24 h after surgery in the acupuncture group were superior to those in the medication group (P < 0.05, P < 0.01). The beta-endorphin content at 0, 8, 16 and 48 h after surgery in both groups were increased, and the acupuncture group was superior to the medication group (all P < 0.05). The security class after surgery in the acupuncture group was higher than that in the medication group (P < 0.05).. The analgesic effect and safety of electroacupuncture at Neimadian(Extra) in postoperation of abdominal surgery are superior to those of the PCIA with Sufentanil.

Topics: Abdomen; Acupuncture Analgesia; Acupuncture Points; Adolescent; Adult; Aged; beta-Endorphin; Electroacupuncture; Female; Humans; Male; Middle Aged; Pain, Postoperative; Young Adult

Recent studies suggest that preemptive analgesia may be effective in reducing postoperative pain. One physiologic explanation may be interference with the endogenous opioid response. We investigated whether long-lasting preoperative preemptive analgesia may have an effect on the hormonal stress response after total hip replacement.. 42 patients scheduled for elective hip replacement for coxarthrosis were randomized to receive, on the day before the operation, either 5 ml*h(-1) ropivacaine 0.2% (study group, n = 21) or 5 ml*h(-1) saline (control group, n = 21). Postoperative analgesia was achieved in both groups by patient-controlled epidural analgesia (PCEA) with ropivacaine 0.2%. The main outcome measure was the concentration of authentic beta-endorphin [1-31] in plasma up to 4 days after surgery. Additional parameters included concentrations of adrenocorticotrope hormone and cortisol.. Both groups were comparable concerning preoperative parameters and pain scores. Epidural blocks were sufficient in all patients for operative analgesia. Preemptive analgesia was performed for 11-20 hours in both groups and led to significantly decreased pain scores before surgery. Preemptive analgesia with epidural ropivacaine did not lead to decreased concentrations of beta-endorphin [1-31] before the start of surgery or in the postoperative period. Furthermore, no differences could be detected in the time course of beta-endorphin and adrenocorticotrope hormone after surgery. However, cortisol concentrations differed significantly between groups before the operation, but showed a comparable rise after surgery.. Differences in postoperative pain after preemptive analgesia do not seem to be due to an altered endogenous opioid response.

Topics: Adrenocorticotropic Hormone; Adult; Aged; Analgesia, Epidural; Arthroplasty, Replacement, Hip; beta-Endorphin; Double-Blind Method; Female; Humans; Hydrocortisone; Male; Middle Aged; Pain, Postoperative; Prospective Studies

To evaluate the effects of patient-controlled analgesia (PCA) with small dose ketamine combined with morphine on analgesia and influence thereof on the plasma beta-endorphin (EP) level in the patients after radical operation for esophageal carcinoma.. Thirty ASAI-II patients, aged 35-65, weighing 42-75 kg, with visual analogue score>or=3, undergoing elective radical operation for esophageal carcinoma under general anesthesia received intravenous morphine 2 - 3 mg were randomly divided into 2 equal groups: group m receiving morphine 0.02 mg.kg(-1).h(-1), and with group mk receiving morphine 0.02 mg.kg(-1).h(-1) combined with ketamine 0.08 mg.kg(-1).h(-1) for 50 h. In the course of treatment the patients received intravenous injection of morphine 2-3 mg when the VAS was >or=3. VAS was recorded 4, 8, 20, 24, and 48 h after operation. The amount of morphine used after operation, PCA button pressing times (effective/active), side effects, and vital signs including pulse, saturation of blood oxygen, respiratory rate, heart rate, and average arterial pressure were recorded. Central venous blood samples were collected when entering the operation room (T0), by the end of operation (T1), and 6 h (T2), 24 h (T3), and 48 h (T4) after operation respectively to examine the beta-endorphin level.. During the period 4-48 h after operation the VAS scores of the group mk were significantly lower than those of the group m in activity state (all P<0.05) and were not significantly different those of the group m at resting state (all P>0.05). The total amount of morphine consumed and the actual PCA button pressing times were significantly less in the group mk than in the group m (both P<0.05). The incidence rates of nausea, vomiting, and pruritus of the group mk were all significantly lower than those of the group m (all P<0.05). There were not significant differences in the incidence rates of dreaming and pseudoesthesia between these 2 groups. All the vital signs were stable in the 2 groups. The plasma beta-EP levels at the time point T1 of these 2 groups were both significantly higher than those at T0 (both P<0.05). The plasma beta-endorphin levels at T2-4 of the group mk decreased gradually from the level at T1 to the level at T0, and the plasma beta-endorphin levels of the group m rapidly decreased from the level at T0 to the T0 level and remained at this level to the 48 h after operation.. The combination of small dose of ketamine with morphine provides optimal analgesia with low side-effect rate and little effect on the plasma beta-EP level.

Topics: Adult; Aged; Analgesia, Patient-Controlled; beta-Endorphin; Esophageal Neoplasms; Female; Humans; Ketamine; Male; Middle Aged; Morphine; Pain, Postoperative; Treatment Outcome

Endogenous opioids released from leukocytes extravasating into injured tissue can interact with peripheral opioid receptors to inhibit nociception. Animal studies have shown that the homing of opioid-producing leukocytes to the injured site is modulated by spinal blockade of noxious input. This study investigated whether epidural analgesia (EDA) influences the migration of beta-endorphin (END) and/or met-enkephalin (ENK)-containing leukocytes into the subcutaneous wound tissue of patients undergoing abdominal surgery. In part I patients received general anesthesia combined either with intra- and postoperative EDA (with bupivacaine and fentanyl) or with postoperative patient controlled intravenous analgesia (PCIA; with the opioid piritramide). In part II patients received general anesthesia combined with either epidural fentanyl or bupivacaine which was continued postoperatively. Samples of cutanous and subcutanous tissue were taken from the wound site at the beginning, at the end and at various times after surgery, and were examined by immunohistochemistry for the presence of END and ENK. We found that (i) epidural bupivacaine, fentanyl and PCIA provided similar and clinically acceptable postoperative pain relief; (ii) compared to PCIA, epidural bupivacaine or fentanyl did not change the gross inflammatory reaction within the surgical wound; (iii) opioid-containing leukocytes were almost absent in normal subcutaneous tissue but migrated to the inflamed wound tissue in ascending numbers within a few hours, reaching a peak at about 24 h after surgery; (iv) compared to PCIA, EDA resulted in significantly decreased homing of END-containing leukocytes to the injured site at 24 h after surgery; and (v) the magnitude of this decrease was similar regardless of the epidural medication. These findings suggest that nociceptive but not sympathetic neurons are primarily involved in the attraction of opioid-containing leukocytes during early stages of inflammation.

Topics: Adjuvants, Anesthesia; Aged; Analgesia, Patient-Controlled; Analgesics, Opioid; Anesthesia, Epidural; Anesthetics, Local; beta-Endorphin; Bupivacaine; Cell Movement; Enkephalin, Methionine; Female; Fentanyl; Humans; Leukocytes; Longitudinal Studies; Male; Middle Aged; Nociceptors; Pain, Postoperative; Pirinitramide; Subcutaneous Tissue; Sympathetic Fibers, Postganglionic; Wound Healing

Opioid receptors are expressed on peripheral nerve endings and opioid peptides (beta-endorphin, END) are produced in various immune cells of synovial tissue after knee trauma. Because corticotropin-releasing hormone (CRH) acts through its receptors on END-containing immune cells, this randomized controlled trial investigated whether the intra-articular (IA) injection of CRH reduces postoperative pain intensity and supplemental analgesic consumption in patients undergoing arthroscopic knee surgery.. Patients were randomly assigned to one of the following IA and IV treatments: group saline (SAL) (n=17) received isotonic SAL IA and 10 microg CRH IV; group CRH (n=16) received 10 microg CRH IA and SAL IV; group CNL (n=18) received 10 microg CRH plus 0.12 mg naloxone IA and SAL IV. Patients pain intensity at rest and during exercise, cortisol plasma concentrations as well as supplemental analgesics were documented. Immunohistochemistry analyzed colocalization of CRH receptors and END.. IA but not IV CRH resulted in a significant but short lasting reduction of postoperative pain under both resting and exercise conditions without changes in cortisol plasma concentrations. Coadministration of naloxone reversed this pain reduction under resting but not exercise conditions. The majority of CRH receptor expressing cells contained END within synovial tissue.. In conclusion, this first clinical trial provides preliminary evidence for a short but not robust analgesic effect of a single dose of IA CRH in patients undergoing arthroscopic knee surgery. Further clinical studies will have to examine different doses of IA CRH-induced analgesia and to support the involvement of opioid peptides.

Topics: Adult; Aged; Arthroscopy; beta-Endorphin; Corticotropin-Releasing Hormone; Dose-Response Relationship, Drug; Drug Combinations; Exercise; Hormones; Humans; Immunohistochemistry; Injections, Intra-Articular; Injections, Intravenous; Knee Injuries; Knee Joint; Middle Aged; Naloxone; Pain, Postoperative; Receptors, Corticotropin-Releasing Hormone; Rest; Severity of Illness Index; Synovial Membrane

The function of beta-endorphin immunoreactive material (IRM) released under perioperative conditions remains to be clarified. In 17 patients undergoing orthopedic surgery, we determined beta-endorphin IRM in venous blood plasma and in cerebrospinal fluid (CSF) before surgery (t(A)); after termination of surgery and general anesthesia, but still under spinal anesthesia (t(B)); on occurrence of postoperative pain (t(C)); and 1 day after the operation (t(D)). Pain severity was rated by the patients by using a visual analog scale. Patients felt postoperative pain (t(C)), but they felt no pain at times t(A), t(B), and t(D). beta-Endorphin IRM plasma levels before surgery (t(A)) or with postoperative pain (t(C)) proved to be significantly higher than levels determined just after surgery, but still under spinal anesthesia (t(B)), or those determined 1 day after the operation (t(D)); beta-endorphin IRM plasma levels at times t(A) and t(C) correlated positively with postoperative pain severity (t(C)). beta-Endorphin IRM CSF levels after surgery, but still under spinal anesthesia (t(B)), were significantly higher than levels determined at times t(A), t(C), or t(D). No correlation was found between beta-endorphin IRM CSF levels and pain severity. In conclusion, postoperative pain severity appears to be related to beta-endorphin IRM levels in plasma before surgery as well as with postoperative pain; the analgesic significance of this material remains to be elucidated.

Topics: Adult; Aged; Aged, 80 and over; Anesthesia, Intravenous; Anesthesia, Spinal; Anesthetics, Intravenous; Arthroplasty, Replacement, Hip; Arthroplasty, Replacement, Knee; beta-Endorphin; Female; Humans; Male; Midazolam; Middle Aged; Pain Measurement; Pain, Postoperative; Preanesthetic Medication; Propofol; Radioimmunoassay

Peripheral neuronal barrage from tissue injury produces central nervous system changes that contribute to the maintenance of postoperative pain. The therapeutic approaches to blocking these central changes remain controversial, because previous studies have not differentiated presurgical interventions from those administered after tissue injury, yet before pain onset. In this study, we evaluated the relative contributions of blockade of nociceptive input during surgery or during the immediate postoperative period on pain suppression. Subjects were randomly allocated to one of four groups: preoperative 2% lidocaine, postoperative 0.5% bupivacaine, both, or placebo injections. General anesthesia was induced and third molars extracted. Pain was assessed over 4 h and at 24 and 48 h. The beta-endorphin in blood samples increased twofold during surgery, which is indicative of activation of the peripheral nociceptive barrage in response to painful stimuli. Pain was decreased in the immediate postoperative period in the bupivacaine groups, whereas it increased in the lidocaine group over time. Pain intensity was less 48 h after surgery in the groups whose postoperative pain was blocked by the administration of bupivacaine, but no effect was demonstrated for the preoperative administration of lidocaine alone. These results in the oral surgery pain model suggest that minimizing the peripheral nociceptive barrage during the immediate postoperative period decreases pain at later time periods. In contrast, blocking the intraoperative nociceptive barrage does not appear to contribute significantly to the subsequent reduction in pain.. Suppression of postoperative pain immediately after surgery attenuates the pain experienced 1 to 2 days after surgery. These findings suggest that pain after minor surgery can be prevented by blocking the development of pain processes that amplify pain for days after surgery.

Topics: Acetaminophen; Adult; Analgesics, Non-Narcotic; Analgesics, Opioid; Anesthesia, General; Anesthesia, Local; beta-Endorphin; Codeine; Double-Blind Method; Female; Humans; Male; Nociceptors; Pain Measurement; Pain, Postoperative; Peripheral Nervous System; Surveys and Questionnaires

To evaluate the ability of various subjective and objective measurements to determine the presence and degree of postoperative pain in cats.. Randomized controlled prospective clinical study.. 18 healthy client-owned cats.. Cats were randomly assigned to 3 groups of 6: control, tenectomy, and onychectomy. Jugular catheters were placed the day prior to surgery. All surgeries were performed by the same surgeon, and all observations were made by the same blinded trained observer. One hour prior to surgery and at assigned intervals for 36 hours after surgery, heart rate, respiratory rate, and rectal temperature were measured. Scores were assigned for 3 interaction responses, including response to palpation, by use of simple descriptive scales, and to 2 pain assessments by use of visual analogue scales. Blood was collected to measure plasma beta-endorphin and cortisol concentrations. Butorphanol was administered to all cats before surgery and to any cat subjectively assessed to be experiencing pain after surgery.. Only visual analogue scale scores and response to palpation scores differed significantly between control and surgical groups.. Determination of the presence of pain in cats can be made on the basis of observation and interaction by a trained observer. Physiologic measurements, including plasma cortisol and beta-endorphin concentrations, did not differentiate between control cats and cats that underwent surgery.

Topics: Analgesics, Opioid; Animals; beta-Endorphin; Body Temperature; Butorphanol; Cat Diseases; Cats; Heart Rate; Hoof and Claw; Hydrocortisone; Pain Measurement; Pain, Postoperative; Palpation; Prospective Studies; Respiration; Tendons; Time Factors

Our objective was to determine the least invasive surgical procedure; to do this we compared postoperative pain, duration of ileus, and level of neurohormonal stress response after laparoscopic cholecystectomy (LC) and open cholecystectomy (OC). Postoperative recovery of patients was faster after LC than OC but comparison of the neurohormonal stress response after laparoscopic and open surgical procedures revealed conflicting results. Forty-one consecutive patients with noncomplicated gallstones were randomized for LC (N = 25) and OC (N = 16). The stress level was evaluated in patients before surgery by the Hamilton anxiety scale. Postoperative pain was assessed by a visual analogic scale (VAS) pain score and by the amount of analgesic drugs (propacetamol) administered, while the duration of ileus was determined by the delay between surgery and the time to first passage of flatus as well by the colonic transit time (CTT) measured by radiopaque markers. Plasma concentrations of anti-diuretic hormone (ADH), adrenocorticotropic hormone (ACTH), beta-endorphin (BE), neurotensin (NT), and aldosterone (Ald) were measured before and during surgery as well as 2 and 5 hr after the surgery (D0) and on the day following surgery (D1). Urinary cortisol (uCOR) and urinary catecholamine metabolites were assessed before surgery, during D0, and on D1. Patient characteristics, the duration of surgery, and the doses of anesthetic drugs were not different in LC and OC. In LC patients the VAS pain score and the doses of postoperative antalgics were lower (P < 0.05), the time to first passage of flatus was shorter (P < 0.001), and the CTT tended to be shorter (54 +/- 12 hr vs 81 +/- 17) compared to OC patients. Patients who required the highest doses of postoperative antalgics had the longest delay to first passage of flatus (P < 0.01). During surgery, all neurohormonal parameters increased compared to the preoperative period (P < 0.05), and only plasma NT concentrations were lower during LC than OC (P < 0.05). During the postoperative period, ACTH, BE, Aid, catecholamines, and uCOR concentrations were lower in LC than in OC (P < 0.05). Concentrations of hormonal parameters were higher when the duration of surgery increased (P < 0.05). A greater need for propacetamol to relieve pain was associated with a greater increase in BE, ACTH, and urinary catecholamine levels (P < 0.05-P < 0.005). When the time to first passage of flatus was delayed, levels of BE, ACTH, and catecholamine

Topics: Adrenocorticotropic Hormone; Analgesics; beta-Endorphin; Catecholamines; Cholecystectomy; Cholecystectomy, Laparoscopic; Female; Humans; Hydrocortisone; Intestinal Obstruction; Male; Middle Aged; Pain Measurement; Pain, Postoperative; Stress, Physiological; Vasopressins

After total knee arthroplasty, patients regularly suffer from severe pain. It is unclear whether epidural or systemic pain therapy is superior in terms of postoperative pain relief, patients' comfort and side effects. A new therapeutic approach, intraarticular opioids, has been suggested with the detection of opioid receptors in inflamed tissue. This method has proven suitable for clinical use in small operations (e.g. knee arthroscopy). In this study, we compared epidural analgesia and intraarticular application of morphine plus "on-demand" intravenous analgesia to "on-demand" intravenous analgesia alone.. Thirty-seven patients, scheduled for total knee arthroplasty, were randomly assigned to three treatment groups: in group 1 (EPI) patients received bolus doses of morphine via an epidural catheter; in group 2 (IA) an intraarticular bolus of 1 mg of morphine was applied at the end of the operation with subsequent use of a patient-controlled analgesia (PCA) pump; group 3 (Control), in which only PCA was provided, served as control for both analgesic procedures. Main outcome measures included visual analogue pain scales, total morphine consumption, and stress hormones.. No statistically significant differences in visual analogue pain scales could be detected between the three groups. Application of intraarticular morphine did not reduce the amount of analgesics required for postoperative analgesia as compared to intravenous analgesia alone. Application of epidural morphine significantly suppressed beta-endorphine release, but did not significantly influence other stress hormones as compared to the control group.. Epidural and intravenous analgesia after total knee arthroplasty are equivalent methods of pain relief. In major orthopaedic procedures, application of intraarticular morphine does not reduce analgesic requirements.

Topics: Adrenocorticotropic Hormone; Aged; Analgesia; Analgesia, Epidural; Analgesia, Patient-Controlled; Analgesics, Opioid; Arthroplasty, Replacement, Knee; beta-Endorphin; Female; Humans; Infusions, Intravenous; Injections, Intra-Articular; Male; Morphine; Pain Measurement; Pain, Postoperative; Prospective Studies

Topics: Analgesia; beta-Endorphin; Humans; Neoplasms; Pain, Intractable; Pain, Postoperative

Peripheral nociceptive barrage after tissue injury results in acute pain and a variety of physiologic responses, including pituitary secretion of beta-endorphin. This study evaluated whether administration of the pharmacologically active S(+)-isomer of ibuprofen suppresses acute pain and plasma beta-endorphin levels in the oral surgery model of acute pain.. Subjects in a single-dose, double-blind, parallel-group study received either 200 mg S(+)-ibuprofen, 400 mg S(+)-ibuprofen, 400 mg racemic ibuprofen, or placebo. Both doses of S(+)-ibuprofen resulted in significantly greater analgesia over the first 60 minutes in comparison to racemic ibuprofen and placebo; the 400 mg dose of S(+)-ibuprofen also produced greater analgesia at 2 and 3 hours. Plasma levels of immunoreactive beta-endorphin decreased over time coincident with the onset of analgesia in all groups but were significantly less than placebo after both doses of S(+)-ibuprofen from 30 to 120 minutes.. These findings show that, compared with racemic ibuprofen, administration of the S(+)-isomer of ibuprofen results in faster analgesic onset, greater peak analgesia, similar duration of action, and a low incidence of adverse effects, while suppressing nociceptive activation of the pituitary-adrenal axis.

Topics: Adult; Analgesics, Non-Narcotic; beta-Endorphin; Double-Blind Method; Female; Humans; Ibuprofen; Isomerism; Male; Oral Surgical Procedures; Pain Measurement; Pain, Postoperative; Time Factors; Treatment Outcome

Peripheral afferent neuronal barrage from tissue injury produces central nervous system hyperexcitability which may contribute to increased postoperative pain. Blockade of afferent neuronal barrage has been reported to reduce pain following some, but not all, types of surgery. This study evaluated whether blockade of sensory input with a long-acting local anesthetic reduces postoperative pain after the anesthetic effects have dissipated. Forty-eight patients underwent oral surgery with general anesthesia in a parallel group, double-blind, placebo-controlled study. Subjects randomly received either 0.5% bupivacaine or saline intraoral injections, general anesthesia was induced with propofol, a non-opioid anesthetic, and 2-4 third molars extracted. Subjects were assessed at 24 and 48 h for postoperative pain and analgesic intake. Blood samples were collected at baseline, intraoperatively and at 1-h intervals postoperatively for measurement of beta-endorphin as an index of CNS response to nociceptor input. Plasma beta-endorphin levels increased significantly from baseline to the end of surgery in the saline group in comparison to the bupivacaine group (P < 0.05), indicating effective blockade of nociceptor input into the CNS by the local anesthetic. Pain intensity was not significantly different between groups at 24 h. Pain at 48 h was decreased in the bupivacaine group as measured by category scale and graphic rating scales for pain and unpleasantness (P < 0.05). Additionally, subjects in the bupivacaine group self-administered fewer codeine tablets for unrelieved pain over 24-48 h postoperatively (P < 0.05). These data support previous animal studies demonstrating that blockade of peripheral nociceptive barrage during and immediately after tissue injury results in decreased pain at later time points. The results suggest that blockade of nociceptive input by administration of a long-acting local anesthetic decreases the development of central hyperexcitability, resulting in less pain and analgesic intake.

Topics: Adult; Analgesics, Opioid; Anesthetics, Local; beta-Endorphin; Bupivacaine; Codeine; Double-Blind Method; Female; Humans; Male; Molar, Third; Nerve Block; Neurons, Afferent; Pain; Pain, Postoperative; Peripheral Nerves; Self Administration; Tooth, Impacted

Release of beta-endorphin is modulated by physiologic stress and a variety of hormonal and pharmacologic factors. Prostaglandin E2 inhibits release of beta-endorphin and corticotropin from pituitary corticotroph cells, suggesting that suppression of prostaglandin levels should increase beta-endorphin release. This hypothesis was tested by administration of 600 mg ibuprofen before surgical stress in humans in comparison to placebo and methylprednisolone. Plasma samples were analyzed for immunoreactive beta-endorphin with concurrent measurement of pain and apprehension. Levels of immunoreactive beta-endorphin increased during surgery in the placebo group but were significantly greater in the group of patients pretreated with ibuprofen. Methylprednisolone suppressed intraoperative immunoreactive beta-endorphin, compared with both placebo and ibuprofen. Parallel in vivo and in vitro studies indicate that nonsteroidal anti-inflammatory drug potentiation of endorphin release is mediated at the level of the pituitary corticotroph cell. These results show that ibuprofen enhances pituitary release of beta-endorphin by corticotroph cells in response to stress.

Topics: Adult; Analysis of Variance; Animals; Anti-Inflammatory Agents; Anti-Inflammatory Agents, Non-Steroidal; beta-Endorphin; Female; Humans; Ibuprofen; Male; Methylprednisolone; Pain, Postoperative; Pituitary Gland; Rats; Time Factors; Tooth Extraction; Tooth, Impacted; Toothache; Treatment Outcome

We studied neuroendocrine response in the postoperative pain relief in pediatric patients treated with two analgesic techniques (conventional intravenous analgesia and patient controlled analgesia).. A double blind study was made in 30 patients, 6-14 year-old children, under total intravenous anesthesia for programmed surgery. An intravenous analgesia dose of 0.5 mg/Kg was given 10 minutes before operation was finished. Postoperative analgesia was achieved by two techniques: A. Patient controlled analgesia (PCA), and B. Conventional intravenous analgesia every 6 hours. Hormones measurements were made (catecholamines, cortisol, ACTH and beta-endorphin), hemodynamic monitoring (blood pressure and heart rate), and pain measurement (Hannallah's score) in both pre and postoperative times (1, 6 and 24 hours after operation).. Pain score was low and without significant differences in both groups (p > 0.05). beta-endorphin level decreased in both groups, and a cortisol and catecholamine level increase was noticed at 6 hours after operation; these changes were less significant in PCA group (p < 0.001). ACTH level did not change significantly in both groups. Hemodynamic monitoring measurements were not significantly different.. Both analgesic techniques were appropriate to postoperative pain relief in pediatric patients. Low pain score shows better conditions to attend these patients. We suggest PCA technique is better to treat postoperative stress response following pediatric surgery.

Topics: Adolescent; Adrenocorticotropic Hormone; Analgesia, Patient-Controlled; Analgesics; beta-Endorphin; Catecholamines; Child; Double-Blind Method; Hemodynamics; Humans; Hydrocortisone; Pain Measurement; Pain, Postoperative

Opioids produce analgesia by interacting with local opioid receptors in peripheral inflamed tissue. This study investigated whether endogenous ligands of these receptors are present in synovia and whether such opioid peptides can inhibit pain by activation of intra-articular opioid receptors. Samples of synovium from 8 patients undergoing arthroscopic knee surgery were examined by immunohistochemistry for the presence of beta-endorphin, met-enkephalin, and dynorphin. All tissue samples showed synovitis. Inflammatory cells stained strongly for beta-endorphin and met-enkephalin but not for dynorphin. To find out whether blockade of intra-articular opioid receptors affected pain, we randomly assigned 22 patients undergoing arthroscopic knee surgery to receive naloxone (0.04 mg) intra-articularly (n = 10) or intravenously (n = 12); each patient received a placebo injection into the other site. Postoperative pain was assessed by visual analogue scale, a numerical rating scale, the McGill pain questionnaire, and supplementary analgesic consumption during the next 24 h. All pain scores were higher in the intra-articular naloxone group than in the intravenous naloxone group. The differences were significant (p < 0.05) during the first 4 h. Supplementary analgesic consumption was significantly higher in the intra-articular group (52.5 [14.0] vs 15.6 [8.0] mg diclofenac, p < 0.05). Opioid peptides are present in inflamed synovial tissue and can inhibit pain after knee surgery through an action specific to intra-articular opioid receptors. These findings expand the gate control theory of pain and suggest new approaches such as the development of peripherally acting opioid analgesics without central side-effects.

Topics: Adult; Aged; Arthroscopy; beta-Endorphin; Double-Blind Method; Dynorphins; Endorphins; Enkephalin, Methionine; Humans; Immunohistochemistry; Injections, Intra-Articular; Injections, Intravenous; Knee Joint; Middle Aged; Naloxone; Pain, Postoperative; Receptors, Opioid; Synovial Membrane; Synovitis

Secretion of pituitary immunoreactive beta-endorphin is hypothesized to modulate the perception of pain. The present study examined this question by evaluating the effects of intravenous placebo or dexamethasone (0.1, 0.32, or 1.0 mg) on suppression of immunoreactive beta-endorphin secretion and development of postoperative pain after the surgical removal of impacted third molars in 48 patients. Compared with placebo, all doses of dexamethasone suppressed the postoperative increase in circulating levels of immunoreactive beta-endorphin. Patients administered 0.1 mg dexamethasone reported greater levels of pain, compared with those given placebo, from 60 through 120 minutes after surgery. Postoperative pain for the 0.32 and 1.0 mg doses did not differ from that for the placebo group. The increased pain after suppression of beta-endorphin release by the low dose of dexamethasone suggests that pituitary secretion of immunoreactive beta-endorphin alleviates postoperative pain under these conditions.

Topics: beta-Endorphin; Corticotropin-Releasing Hormone; Dexamethasone; Dose-Response Relationship, Drug; Humans; Pain, Postoperative; Pituitary Gland

17 patients undergoing cholecystectomy in non-opiate general anaesthesia received tramadol (n = 7) or fentanyl (n = 10) for immediate postoperative pain relief using the on-demand analgesia computer (ODAC). Heart rate, blood pressure, and respiratory rate were monitored at half-hourly intervals during the 6-h trial period. Arterial blood was withdrawn at hourly intervals for blood gas analyses and beta-endorphin plasma level assays. Fentanyl and tramadol serum levels were determined prior to each on-demand bolus injection during the first 2 h of the study. At the end of the trial period, the quality of analgesia was assessed retrospectively using a visual analog scale. Mean opiate consumption was 0.53 +/- 0.1 mg for fentanyl and 412 +/- 11.6 mg for tramadol, resulting in an equipotency ratio of about 1:980 (relating to body wt., consumption/h, and pain score). No correlation was found between body wt.-based opiate requirements and pain score. Heart rate increased slightly but significantly under both opiates. Fentanyl produced a significant drop in mean arterial pressure by a maximum of 16%, while tramadol left mean arterial pressure unchanged. Respiratory rate, which was elevated initially, dropped significantly in both groups. Arterial pO2 and pCO2 were within the normal range throughout the observation period, reflecting the absence of respiratory side effects. Opiate blood levels showed major inter- and intraindividual variations (minimal and maximal levels for fentanyl ranged from 0.44-3.44 ng/ml, for tramadol from 272-1,900 ng/ml) and were thus poor predictors of the quality of analgesia.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Aged; beta-Endorphin; Cholecystectomy; Cyclohexanols; Drug Therapy, Computer-Assisted; Endorphins; Female; Fentanyl; Hemodynamics; Humans; Male; Middle Aged; Pain, Postoperative; Respiration; Therapy, Computer-Assisted; Tramadol

Pain medicine still lacks mechanism-specific biomarkers to guide diagnosis and treatment, and defective top-down modulation is an important factor in the pathophysiology of chronic pain conditions. Using modern analytical tools and advanced multivariate statistical analysis, the aim of this study was to revisit two classical potential biomarkers of pro- and anti-nociception in humans (substance P and beta-endorphin), focusing particularly on the cerebrospinal fluid (CSF).. Cross-sectional, comparative, observational study.. Patients with chronic, post-traumatic and/or post-surgical, neuropathic pain refractory to conventional treatment (N = 15) and healthy controls (N = 19) were included.. Samples were taken from CSF and blood, and levels of substance P and beta-endorphin were investigated using a Luminex technology kit.. We found low levels of beta-endorphin in the CSF of neuropathic pain patients (66 ± 11 pcg/mL) compared with healthy controls (115 ± 14 pcg/mL) (P = 0.017). Substance P levels in the CSF did not differ (20 ± 2 pcg/mL, 26 ± 2, P = 0.08). However, our multivariate data analysis showed that belonging to the patient group was associated with low levels of both substances in the CSF. A higher correlation between the levels of beta-endorphin and substance P in CSF was found in healthy controls than in patients (rs  = 0.725, P < 0.001 vs. rs  = 0.574, P = 0.032).. Patients with chronic neuropathic pain due to trauma or surgery had low levels of beta-endorphin in the CSF. We speculate that this could indicate a defective top-down modulation of pain in chronic neuropathic pain. Our results also illustrate the importance of taking a system-wide, multivariate approach when searching for biomarkers.

Topics: Adult; Analgesics; beta-Endorphin; Biomarkers; Chronic Pain; Clinical Trials as Topic; Cross-Sectional Studies; Female; Humans; Male; Middle Aged; Neuralgia; Pain, Intractable; Pain, Postoperative; Substance P

The endogenous opioid beta-endorphin is a known indicator of stress and pain. Opioid anesthesia during operation may prevent postoperative beta-endorphin hypersecretion. We examine the effect on serum beta-endorphin of both preoperative stress and stress of operation under opioids in neonates, infants and preschool children. In order to eliminate the effect of hospitalization anxiety we compared with inpatients of similar age with non-surgical disease.. We included 74 surgical patients (25 neonates, 24 infants, 25 preschool children), and 44 non-surgical inpatients (14 neonates, 12 infants, 18 preschool children). Anesthesia comprised propofol and fentanyl. In presence of pain after extubation, supplementary morphine was administered. Sera were taken preoperatively and 2 h postoperatively in surgical patients, and once in non-surgical patients. Beta-endorphin was tested using ELISA (ng/ml).. In all surgical patients beta-endorphin did not increase significantly after surgery. Neonates showed significantly elevated beta-endorphin preoperatively (mean+/-SD: 2.02+/-0.76) and postoperatively (2.07+/-0.90) compared to neonates with a non-surgical disease (1.05+/-0.34; p<0.005). In contrast, infants (preoperative values: 1.75+/-1.32, postoperative values: 2.00+/-1.83) did not differ from respective non-surgical inpatients (1.49+/-0.70). Before and after surgery, beta-endorphin was significantly elevated in preschool children (7.19+/-1.85, 6.42+/-1.31), as compared with neonates and infants (p<0.0005), and with preschool children with non-surgical disease (1.01+/-0.27; p<0.0005).. Fentanyl/propofol anesthesia, supplemented by postoperative morphine where necessary, protects from surgical stress and postoperative pain, as denoted by no postoperative increase of beta-endorphin in all age groups. Preschool children, who exhibit increased emotional perception, have explicitly high serum beta-endorphin before and after surgery. Preoperative preparation programs might be worthy in this age group. Neonates show a moderate but still significantly high response of beta-endorphin to stress, retained after operation. In contrast, infants tolerated stress better (not increased beta-endorphin pre- and post-operatively).

Topics: Analgesics, Opioid; Anesthesia, Intravenous; Anesthetics, Intravenous; beta-Endorphin; Child, Preschool; Female; Fentanyl; Humans; Infant; Infant, Newborn; Male; Morphine; Pain, Postoperative; Propofol; Stress, Psychological; Treatment Outcome

In the pituitary of lower species, pro-opiomelanocortin is expressed in corticotroph cells of the anterior and in melanotroph cells of the neurointermediate lobe; enzymatic processing in the corticotrophs results in the release of adrenocorticotropic hormone, beta-lipotropin, or beta-endorphin. In the melanotrophs, these fragments are further modified, eg, by N-terminal acetylation. In the human pituitary, these enzyme systems are located within the same cells in the anterior lobe. We studied the reactions of the pro-opiomelanocortin system under preoperative conditions as well as under postoperative pain.. In 17 patients undergoing hip or knee arthroplasty, we determined plasma concentrations of N-acetyl-beta-endorphin immunoreactive material, authentic beta-endorphin [beta-endorphin(1-31)], adrenocorticotropic hormone, beta-lipotropin immunoreactive material, and cortisol, as well as pain severity rated by the patients using a visual analogue scale before surgery, after surgery but still under spinal anesthesia, under postoperative pain, and 1 day after surgery.. Only low levels of N-acetyl-beta-endorphin immunoreactive material were measured in 16 out of 17 patients. High concentrations (1st quartile/median/3rd quartile; pmol/L) of adrenocorticotropic hormone (22.5/55.8/124) and beta-lipotropin immunoreactive material (6.6/34.6/142) were observed under postoperative pain, accompanied by a small increase of beta-endorphin(1-31) concentrations (0.0/6.1/10.9). Preoperatively small but significantly elevated levels of corticotroph-type and melanotroph-type pro-opiomelanocortin derivatives were observed; in contrast, spinal anesthesia suppressed all pro-opiomelanocortin fragment release. Postoperative pain severity correlated with postoperative adrenocorticotropic hormone, beta-lipotropin immunoreactive material, and beta-endorphin(1-31) concentrations.. We conclude that the melanotroph-type pro-opiomelanocortin system is not activated under postoperative pain; the increase of corticotroph-type pro-opiomelanocortin fragment levels is different in quantity and proportion under preoperative conditions or postoperative pain, respectively.

Topics: Adrenocorticotropic Hormone; Aged; Anesthesia, Spinal; Arthroplasty, Replacement, Hip; Arthroplasty, Replacement, Knee; beta-Endorphin; beta-Lipotropin; Blood Specimen Collection; Buffers; Female; Humans; Hydrocortisone; Indicators and Reagents; Male; Middle Aged; Pain Measurement; Pain, Postoperative; Peptide Fragments; Pituitary Gland; Pro-Opiomelanocortin; Prospective Studies

Cyclosporine A (CsA) and morphine have neurotoxic and psychiatric side effects, respectively. Endogenous opiatelike peptides can elicit a number of behavioral responses that mimic the symptoms of psychiatric illness. The purpose of this study was to quantitiate the changes of Met-enkephalin (ME) and beta-endorphin (BE) after administration of CsA and morphine in surgery and to assess the antinociceptive effect.. Pain sensitivity, an antinociceptive indicator in rats, was determined with the hotplate test. Plasma ME and BE levels were measured with radioimmunoassays.. In normal unoperated rats, CsA induced a profound analgesic effect concomitant with an increased plasma ME level on day 1. Morphine produced an analgesic effect on days 1 and 2, with decreased ME levels on days 2 and 3. Coadministration of CsA and morphine prolonged the analgesia from days 1 to 4 and increased the plasma ME level on day 1. No change in plasma BE level was found. In surgically operated rats, CsA induced an analgesic effect and higher ME levels than those in unoperated rats. Interestingly, the combined use of CsA and morphine prolonged the analgesia and increased plasma ME levels from days 1 to 4, with no significant change in plasma BE levels.. Our results showed that CsA can induce antinociception and increase plasma ME levels. This induction can be potentiated by the addition of morphine. Acute neuropsychiatric manifestations in the early posttransplant period might, therefore, be due to induction of ME after coadministration of CsA and morphine.

Topics: Analgesics, Opioid; Animals; beta-Endorphin; Cyclosporine; Enkephalin, Methionine; Immunosuppressive Agents; Male; Mental Disorders; Morphine; Nociceptors; Pain, Postoperative; Postoperative Complications; Rats; Rats, Sprague-Dawley; Transplantation

Topics: Acupressure; Acupuncture Analgesia; Adolescent; Adult; Aged; Appendectomy; Appendicitis; beta-Endorphin; Cholecystectomy; Cholecystitis; Cholelithiasis; Drugs, Chinese Herbal; Ear, External; Female; Humans; Male; Middle Aged; Pain, Postoperative

beta-Endorphin (beta-EP) and methionine-enkephalin (M-EK) are endogenous peptides that play a role in the modification of pain perception and analgesia threshold. In order to understand more about pathophysiology of pain in association with neuroaxial blocks, we evaluated cerebrospinal fluid (CSF) concentrations of beta-EP and M-EK prior to spinal anesthesia (SA) in patients undergoing transurethral resection of prostate (TURP) to determine the correlation between preanesthesia concentrations and the duration of postoperative analgesia and opioid requirements. Twenty-five healthy patients undergoing TURP under SA were enrolled. beta-EP and M-EK were measured with a competitive radioimmunoassay. Mean preoperative beta-EP and M-EK concentrations were 153 +/- 44 and 38 +/- 5 pg/mL, respectively. Those with beta-EP concentrations > 153 pg/mL had significantly longer analgesia (P < 0.01), and lower utilization of morphine in the first postoperative day (P < 0.01). Moreover, patients with milder postoperative pain (visual analog scale score < 4/10) had significantly higher beta-EP concentrations (P < 0.01). A similar correlation was not found with M-EK values. These data suggest that preoperative CSF beta-EP, but not M-EK, concentrations correlate with the duration and quality of postoperative analgesia, as well as opioid requirements after spinal anesthesia.

Topics: Aged; Aged, 80 and over; Analgesia; beta-Endorphin; Enkephalin, Methionine; Humans; Male; Middle Aged; Morphine; Pain, Postoperative; Postoperative Care; Prostate; Prostatic Hyperplasia

The efficacy and safety of morphine sulfate was evaluated in 20 neonates requiring surgery. Following surgery, each subject received an intravenous morphine loading dose (50 micrograms/kg) followed by a continuous infusion (15 micrograms/kg/hr) for a minimum of 24 hours. Heart rate, respiratory rate, and blood pressure were frequently monitored during therapy. Blood samples were obtained following surgery and during and after morphine therapy for analysis of serum morphine and beta-endorphin content. A 12-hour urine collection was obtained 12 hours following the start of the constant morphine infusion for analysis of morphine content. The mean (+/- SD) duration of morphine infusion was 34 +/- 15 hours and a steady-rate serum morphine concentration was 39 +/- 23 ng/ml. The respective serum morphine half-life, elimination rate, and volume of distribution were 6.6 +/- 2.9 hr, 0.126 +/- 0.056 hr-1, and 5.0 +/- 6.8 liters/kg. The mean percentage of unchanged morphine recovered in the urine was 39 +/- 19 of the dose administered over 12 hours. A significant reduction in serum beta-endorphin content was observed following the onset of morphine therapy. No adverse reports were noted that could be attributed to morphine therapy. Continuous morphine therapy appears to be effective in controlling neonatal postoperative pain, as suggested by subjective nursing observations and decreased serum beta-endorphin content.

Topics: Analgesia; beta-Endorphin; Half-Life; Humans; Infant, Newborn; Infant, Newborn, Diseases; Infusion Pumps; Infusions, Intravenous; Morphine; Pain, Postoperative

Topics: Adenocarcinoma; Adrenocorticotropic Hormone; Anesthesia, Endotracheal; Anesthesia, Epidural; beta-Endorphin; Chronic Disease; Enkephalin, Leucine; Humans; Insulinoma; Intraoperative Care; Pain, Postoperative; Pancreatic Neoplasms; Pancreatitis; Postoperative Care; Stress, Physiological

Topics: Adrenocorticotropic Hormone; Adult; beta-Endorphin; Female; Humans; Injections, Epidural; Male; Meperidine; Middle Aged; Morphine; Narcotics; Pain, Postoperative

Postoperative pain relief and stress hormones were examined during the use of continuous epidural infusion of morphine at a rate of 0.1 mg/hr in 30 patients (Group B) after coronary artery bypass grafting. This was compared to our routine method of postoperative analgesia of intravenous morphine 2 mg/2 hr and as needed in another 30 patients (Group A). Continuous epidural morphine infusion required occasional supplementation with intravenous morphine and achieved effective analgesia in 80% of the patients. Pain relief was adequate in 50% of the patients in Group A. The mean dose of morphine used in Group B during the first 3 postoperative days was 5 mg per patient per day and was significantly lower than that used in Group A (mean 18 mg per patient per day). Serum morphine was undetectable (below 2.5 ng/ml) in Group B and was significantly lower than that in Group A (17 ng/ml). Epidural analgesia was associated with adequate postoperative pulmonary and cardiovascular functions; nausea and vomiting occurred in two patients. Levels of postoperative stress, serum cortisol, and beta-endorphin were significantly lower in Group B than in Group A. This study shows that continuous epidural infusion of morphine at a rate of 0.1 mg/hr provides selective and effective pain relief and reduces postoperative stress after cardiac operations. This method of analgesia was also associated with minimal side effects and provides an alternate approach for treatment of pain after cardiac operations.

Topics: Adult; Aged; beta-Endorphin; Cardiac Surgical Procedures; Endorphins; Epidural Space; Hemodynamics; Humans; Hydrocortisone; Injections, Intravenous; Middle Aged; Morphine; Pain, Postoperative; Spinal Canal

Topics: Adult; beta-Endorphin; Female; Humans; Injections, Epidural; Male; Middle Aged; Morphine; Pain, Postoperative

Seven women undergoing abdominal hysterectomy under halothane and nitrous oxide analgesia had plasma samples taken before, during and after surgery for assay of adrenocorticotrophin (ACTH), beta-endorphin, beta-lipotrophin and methionine (Met)-enkephalin immunoreactivity. Plasma ACTH, beta-endorphin and beta-lipotrophin all rose in parallel from the start of surgery and were unaffected by postoperative opiate analgesia. Plasma Met-enkephalin concentrations did not change significantly during the course of the surgery and immediate post-operative period, although the variance of the samples increased at the time of the first skin incision. These data indicate that the stress of surgery and post-operative pain, while producing marked elevations of proopiomelanocortin-derived peptides, are not associated with changes in plasma Met-enkephalin. These data exclude a role for circulating Met-enkephalin in the modulation of surgical pain but do not exclude such a role for beta-endorphin.

Topics: Analgesics, Opioid; beta-Endorphin; Endorphins; Enkephalin, Methionine; Female; Humans; Hysterectomy; Middle Aged; Pain, Postoperative; Radioimmunoassay

It has been hypothesized that the endogenous opioid (endorphin) system is related to biologic stress responses. We have used general surgery as a naturalistic model for studying stress response in humans. Abdominal surgery, but not anesthesia induction, was associated with significant increases in plasma beta-endorphin immunoreactivity and cortisol. Both hormones decreased significantly during post-operative morphine administration. Baseline and mean surgery levels of plasma beta-endorphin immunoreactivity showed an inverse relationship with post-operative analgesic requirement. These data support involvement of the endorphin system in human stress response and in human endogenous analgesic mechanisms. Findings also support the concept that baseline or psychologically stimulated levels of arousal may also be an important determinant in the physiology of stress response and pain perception.

Topics: Adolescent; Adult; beta-Endorphin; Endorphins; Female; Humans; Hydrocortisone; Male; Middle Aged; Morphine; Ovarian Neoplasms; Pain, Postoperative; Radioimmunoassay; Stress, Physiological; Testicular Neoplasms

The relationship between stress and human behavior is studied using general surgery as a stress paradigm. As indices of arousal, presurgery and surgery plasma beta-endorphin and cortisol immunoreactivity are assessed. Behavioral analysis is restricted to the measurement of total morphine usage during the first 24 postoperative hours under standard PRN (as needed) clinical orders. Individual patient morphine requirements vary widely (12-56 mg). Both presurgery and mean surgery plasma beta-endorphin levels significantly predict morphine requirement, and similar, although not so strong, correlations are found for cortisol. Patient age is also found to be negatively correlated with morphine requirement. When multiple regression analysis is used, the variables of plasma beta-endorphin and age predict 70% of the variance in individual morphine requirements.

Topics: Adolescent; Adult; Arousal; beta-Endorphin; Endorphins; Female; Humans; Hydrocortisone; Male; Middle Aged; Morphine; Ovarian Neoplasms; Pain, Postoperative; Stress, Physiological; Testicular Neoplasms

Topics: Adult; beta-Endorphin; Endorphins; Female; Humans; Injections, Spinal; Middle Aged; Morphine; Pain, Postoperative