Chronic postsurgical pain in Europe: An observational study.

BACKGROUND Chronic postsurgical pain (CPSP) is an important clinical problem. Prospective studies of the incidence, characteristics and risk factors of CPSP are needed. OBJECTIVES The objective of this study is to evaluate the incidence and risk factors of CPSP. DESIGN A multicentre, prospective, observational trial. SETTING Twenty-one hospitals in 11 European countries. PATIENTS Three thousand one hundred and twenty patients undergoing surgery and enrolled in the European registry PAIN OUT. MAIN OUTCOME MEASURES Pain-related outcome was evaluated on the first postoperative day (D1) using a standardised pain outcome questionnaire. Review at 6 and 12 months via e-mail or telephonic interview used the Brief Pain Inventory (BPI) and the DN4 (Douleur Neuropathique four questions). Primary endpoint was the incidence of moderate to severe CPSP (numeric rating scale, NRS ≥3/10) at 12 months. RESULTS For 1044 and 889 patients, complete data were available at 6 and 12 months. At 12 months, the incidence of moderate to severe CPSP was 11.8% (95% CI 9.7 to 13.9) and of severe pain (NRS ≥6) 2.2% (95% CI 1.2 to 3.3). Signs of neuropathic pain were recorded in 35.4% (95% CI 23.9 to 48.3) and 57.1% (95% CI 30.7 to 83.4) of patients with moderate and severe CPSP, respectively. Functional impairment (BPI) at 6 and 12 months increased with the severity of CPSP (P < 0.01) and presence of neuropathic characteristics (P < 0.001). Multivariate analysis identified orthopaedic surgery, preoperative chronic pain and percentage of time in severe pain on D1 as risk factors. A 10% increase in percentage of time in severe pain was associated with a 30% increase of CPSP incidence at 12 months. CONCLUSION The collection of data on CPSP was feasible within the European registry PAIN OUT. The incidence of moderate to severe CPSP at 12 months was 11.8%. Functional impairment was associated with CPSP severity and neuropathic characteristics. Risk factors for CPSP in the present study were chronic preoperative pain, orthopaedic surgery and percentage of time in severe pain on D1. TRIAL REGISTRATION Clinicaltrials.gov identifier: NCT01467102.

A follow-up on Acute Pain Services in Germany compared to international survey data.

BACKGROUND After the introduction of instruments for benchmarking, certification and a national guideline for acute pain management, the aim of this study was to describe the current structure, processes and quality of German acute pain services (APS). METHODS All directors of German departments of anaesthesiology were invited to complete a postal questionnaire on structures und processes of acute pain management. The survey asked for staff, techniques and quality criteria, which enabled a comparison to previous data from 1999 and surveys from other countries. RESULTS Four hundred and eight (46%) questionnaires were returned. APS have increased considerably and are now available in 81% of the hospitals, mainly anaesthesia based. However, only 45% fulfilled the minimum quality criteria, such as the assignment of personnel, the organization of patient care during nights and weekends, written protocols for postoperative pain management, regular assessments and documenting pain scores. Staff resources varied considerably, but increased compared to 1999. Two daily rounds were performed in 71%, either by physicians and nurses (42%), by physicians only (25%) or by supervised nurses (31%). Most personnel assigned to the APS shared this work along with other duties. Only 53% of the hospitals had an integrated rotation for training their specialty trainees. CONCLUSIONS The availability of APS in Germany and other countries has increased over the last decade; however, the quality of nearly half of the APS is questionable. Against the disillusioning background of recently reported unfavourable pain-related patient outcomes, the structures, organization and quality of APS should be revisited.

Ultrasound Mapping of Stimulated Finger Flexion During Infra-Clavicular Brachial Plexus Nerve Blockade for Elbow Arthroplasty and Its Correlation To Postoperative Analgesia

Background: Infraclavicular brachial plexus nerve blockade (ICNB) is a very common anesthetic procedure performed for upper extremity surgery at the elbow and distally, however the rate of adequate analgesia is variable among patients. Ultrasound guidance (US) has not been demonstrated to increase the success rate of ICNB when compared to nerve stimulator (NS) guidance. Combined US and NS guided ICNB have not been reported, although there is a call for more trials comparing the two techniques. This study was performed to observe if a specific anatomic region near the axillary artery of the brachial plexus identified by finger flexion with nerve stimulation results in improved postoperative analgesia. Method: Patients undergoing elective elbow arthroplasty received a postoperative ICNB. The angle of the nerve stimulator needle tip and the radial distance from the center of the arterial lumen at which an optimal finger flexion twitch response was observed were measured with ultrasound imaging. Pain scores and postoperative opioid dosages on discharge from the post anesthesia care unit and at 24 hours after surgery were recorded. Results: 11 patients enrolled in this study. Adequate finger flexion response to nerve stimulation that resulted in complete analgesia was more frequently observed when the needle was located in the postero-superior quadrant in relation to the axillary artery. Identifying a specific point near the brachial plexus in relation to the artery that consistently provides superior analgesia is desirable and would lead to improved analgesia and faster onset time of nerve blockade and would reduce the need for other approaches for brachial plexus blockade with their associated disadvantages.

Postoperative Analgesia Following Sciatic Nerve Blockade Administered by Nurse Anesthetists Supervised by Regional Anesthesia Faculty in an Academic Hospital

Introduction: Assessment of expertise in regional anesthesia techniques is traditionally based upon quota fulfillment of procedures during training. Validation of practitioner proficiency in performing procedures in surgical specialties has moved from simple measurement of technical skills to evaluation of global patient outcomes. Complete absence of pain as a result of nerve blockade is the most important clinical endpoint but patient, technical and procedural factors influence results. The purpose of this study was to measure the postoperative pain scores and associated analgesic medication requirements for patients administered sciatic nerve blockade by nurse anesthetists and determine patient or procedural factors that influenced this outcome. Methods: Either nerve stimulator or ultrasound guided sciatic nerve blockade was administered by nurse anesthetists under the supervision of regional anesthesia faculty. Patient demographic data that was collected included gender, body mass index, surgical procedure, and pre-existing chronic pain with associated opioid use. Patient self-reported pain scores and opioid analgesic dosages in the preoperative, intraoperative, immediate postoperative and 24 hour post procedure intervals were recorded. Results: 22 nurse anesthetists administered sciatic nerve blockade to 48 patients during a 36 month interval. Transition from a nerve stimulator to ultrasound guided sciatic nerve block technique resulted in lower mean pain scores. Patients reporting chronic opioid use were observed to have elevated perioperative opioid analgesic requirements and pain scores compared to opioid naïve patients. Conclusion: Effective analgesia is a prime measure for assessing expertise in regional anesthesia and continuous evaluation of this outcome in everyday practice is proposed.

Post-Operative Pain Scores and Level of Regional Anesthesia Expertise: Using Clinical Outcomes to Assess Procedural Proficiency

Background and Objectives: Peripheral nerve blockade requires regional anesthesia skills that trainees learn in several formats. Technical proficiency has shifted from a quota to comprehensive procedural evaluation. Successful nerve blockade is the clinical endpoint validating proficiency but patient, technical and procedural factors influence this result. The purpose of this study was to determine if procedural expertise for sciatic nerve blockade influenced postoperative pain scores and opioid requirements and if patient factors, technique and repetition influenced this outcome. Method: Sciatic nerve blockade by nerve stimulation and ultrasound guidance and training level of the resident performing the procedure were recorded. Patient obesity, trauma, chronic pain, opioid use and preoperative pain scores were compared to post-procedure pain scores and opioid analgesic requirements. Results: 102 patients received sciatic nerve blockade from 47 trainees over a 36 month interval. A significant relation between training level and improved pain scores was not demonstrated but transition from nerve stimulation to ultrasound guidance lowered scores in all groups. Nerve blockade failure was frequent with chronic opioid use and trauma. Conclusion: Analgesic outcomes should be an integral part of assessment of proficiency in regional anesthesia techniques. Evaluating outcomes of procedures throughout training will longitudinally assess technical expertise.

The role of morphine-6-glucuronide (M6G) in pain control

Morphine-6beta-D-glucuronide (M6G) is an analgesically active metabolite of morphine, accounting for approximate to10% of the morphine dose when administered by systemic routes to humans. Although M6G is more hydrophilic than morphine, it crosses the blood-brain barrier, albeit relatively slowly. For this reason, it is generally thought that, after chronic dosing, M6G contributes significantly to the analgesic effects of systemically administered morphine. Owing to its polar nature, M6G is cleared from the systemic circulation primarily via renal elimination. As M6G accumulates in patients with renal impairment, there is an increased risk of M6G-induced respiratory depression in renal failure patients who are being dosed chronically with systemic morphine. Consistent with its analgesic and respiratory depressant properties, M6G binds to the p-opioid receptor in a naloxone-reversible manner. Although the affinity of M6G for the mu-opioid receptor is similar to or slightly less than that of morphine, preclinical studies in rodents show that M6G is one to two orders of magnitude more potent than morphine when administered by central routes. This major discrepancy between the markedly higher intrinsic antinociceptive potency of M6G relative to morphine, despite their similar p-opioid receptor binding affinities, is difficult to reconcile. It has been proposed that M6G mediates its pain-relieving effects through a novel 'M6G opioid receptor', while others have argued that M6G may have higher efficacy than morphine for transduction of intracellular events. When administered by parenteral routes to rodents, M6G's antinociceptive potency is no more than twofold higher than morphine. In humans, the analgesic efficacy and respiratory depressant potency of M6G relative to morphine have been assessed in a number of short-term studies involving the intrathecal or intravenous routes of administration. For example, in hip replacement patients, intrathecal M6G provided excellent postoperative analgesia but the occurrence of late respiratory depression in 10% of these patients raised serious concern about safety. In postoperative patients, intravenous M6G administered by means of patient-controlled analgesia (PCA), or bolus plus PCA, produced no analgesia in one study and limited analgesia in another. Similarly, there was a lack of significant analgesia in healthy volunteers who received intravenous M6G for the alleviation of experimental pain (carbon dioxide applied to the nasal mucosa). In contrast, satisfactory analgesia was produced by bolus doses of intravenous M6G administered to patients with cancer pain, and to healthy volunteers with experimentally-induced ischaemic, electrical or thermal (ice water) pain. Studies to date in healthy volunteers suggest that intravenous M6G may be a less potent respiratory depressant and have a lower propensity for producing nausea and vomiting than morphine. However, it is unclear whether equi-analgesic doses of M6G and morphine were compared. Clearly, more extensive short-term trials, together with studies involving chronic M6G administration, are necessary before the potential clinical utility of M6G as an analgesic drug in its own right can be determined.

Postoperative analgesic requirements - total laparoscopic hysterectomy versus vaginal hysterectomy

Background: There is limited information available on the requirement for postoperative analgesic drugs in patients submitted to total laparoscopic hysterectomy (TLH) compared with patients undergoing vaginal hysterectomy (VH). Aim: To compare the postoperative analgesic requirements in patients who underwent a TLH with patients who had a VH. Methods: Chart review of 53 patients who had TLH and 47 who had VH and were seen postoperatively by an acute pain management service in order to assess postoperative analgesic requirements. Patient controlled analgesia (PCA) was part of the standard protocol for postoperative pain management. Analgesic requirement was recorded as the mean doses of morphine and number of days that patients used non-steroidal anti-inflammatory drugs (NSAIDs), oxycodone and tramadol. Results: The requirement for total morphine was approximately half the dose in patients who had a TLH (10.8 +/- 12.6 mg) compared with patients who had a VH (19.4 +/- 21.9 mg) (P 0.017). The length of use of NSAIDs was significantly reduced in patients who had undergone a TLH (2.0 +/- 0.95 days) as compared with patients who had a VH (2.85 +/- 1.1 days) (P < 0.0001). Conclusions: Patients submitted to TLH require less postoperative analgesic drugs when compared with patients who had VH. Prospective randomised trials are warranted to compare analgesic requirements between patients submitted to TLH and VH.

Postoperative analgesic effect, of preoperatively administered dexamethasone, after operative fixation of fractured neck of femur: randomised, double blinded controlled study.

Background: Fractured neck of femur is a common cause of hospital admission in the elderly and usually requires operative fixation. In a variety of clinical settings, preoperative glucocorticoid administration has improved analgesia and decreased opioid consumption. Our objective was to define the postoperative analgesic efficacy of single dose of dexamethasone administered preoperatively in patients undergoing operative fixation of fractured neck of femur. Methods: Institutional ethical approval was granted and written informed consent was obtained from each patient. Patients awaiting for surgery at Cork University Hospital were recruited between July 2009 and August 2012. Participating patients, scheduled for surgery were randomly allocated to one of two groups (Dexamethasone or Placebo). Patients in the dexamethasone group received a single dose of intravenous dexamethasone 0.1 mg kg -1 immediately preoperatively. Patients in the placebo group received the same volume of normal saline. Patients underwent operative fixation of fractured neck of femur using standardised spinal anaesthesia and surgical techniques. The primary outcome was pain scores at rest 6 h after the surgery. Results: Thirty seven patients were recruited and data from thirty patients were analysed. The groups were similar in terms of patient characteristics. Pain scores at rest 6 h after the surgery (the principal outcome) were lesser in the dexamethasone group compared with the placebo group [0.8(1.3) vs. 3.9(2.9), mean(SD) p = 0.0004]. Cumulative morphine consumption 24 h after the surgery was also lesser in the dexamethasone group [7.7(8.3) vs. 15.1(9.4), mean(SD) mg, p = 0.04]. Conclusions: A single dose of intravenous dexamethasone 0.1 mg kg -1 administered before operative fixation of fractured neck of femur improve significantly the early postoperative analgesia. Trial registration: ClinicalTrials.gov identifier: NCT01550146, date of registration: 07/03/2012

Postoperative Bowel Function and Related Factors in Enhanced Recovery Protocol with Patients Undergoing Hepatectomy

Patients’ bowel dysfunction is a major factor that weakens the results of surgical care as it can cause pain and weaken patients’ rehabilitation. Bowel dysfunction is a common postoperative problem, yet most incidents remain undocumented. The nursing profession has a significant role in enhancing the bowel function postoperatively. However, studies of postoperative bowel function after hepatectomy are scarce and somewhat incongruous. Enhanced recovery protocols are innovative models of care aiming for better outcomes of surgical care. Enhanced recovery protocols can improve gastrointestinal function after surgery, yet patients are also known to be satisfied with their care. The aim was to investigate if postoperative bowel function day varies between patients in terms of age, gender, ASA score, type of surgery, histology, patients’ experienced pain and experienced satisfaction three days after discharge and three months after operation in patients undergoing hepatectomy. The goal was to produce information for basis of scientific research, to give nurses in clinical setting more tools to work with hepatectomy patients undergoing enhanced recovery protocol and to produce information to nurse managers to use in process management of patients undergoing enhanced recovery protocol. The design of this study is descriptive. Data was collected retrospectively from hepatectomy patients (n = 134) undergoing enhanced recovery protocol within the first year of enhanced recovery protocol implementation. The data was based on registers and analyzed statistically. Mean age of patients was 62 years and mean day of discharge was 4. Main (n = 72) histology of the patients was colorectal liver metastases. Mean bowel function day was 3. Most of the patients were very satisfied or satisfied with the care three days after discharge (99%) and three months (90%) after operation. Most of the patients (72%) experienced moderate pain three days after discharge, but three months after operation 47% of the patients did not experience pain and 48% experienced moderate pain. There were no statistically significant differences in bowel function between different age groups, genders, ASA score groups or histologies. Neither were there statistically significant differences in postoperative bowel function in terms of experienced satisfaction or pain. There were statistically significant differences in postoperative bowel function between different types of surgery (p < 0.01). Nurses should take into consideration hepatectomy patients’ type of surgery and pay special attention in supporting major open hepatectomy patients’ postoperative bowel function. Nurses should educate patients undergoing major open hepatectomy about prolonged postoperative bowel function.

Iniltration vs. instillation of ropivacaine 7.5% in radical mastectomies for postoperative analgesia

Objective: Determining the effectiveness of iniltration versus instillation with 7.5% ropivacaine in reducing the intensity of postoperative pain in patients undergoing a radical mastectomy. Material and methods: Clinical, prospective, and comparative analytical study in a sample of 20 female patients between 20 and 60 years of age, ASA I and II, weight 50-90 kg, who were divided into 2 groups (10 patients each). In Group 1 infiltration with ropivacaine 7.5% (20 ml) was applied prior to closure of the surgical wound, meanwhile in Group 2 ropivacaine 7.5% (20 ml), was instilled into the surgical wound. P ain intensity was assessed by a visual analog scale (V AS) upon extubation. The need for rescue medication and the incidence of nausea and vomiting were measured from 0 to 30 minutes postoperatively and at 2, 4, 8 and 12 hours. Results: There was no statistical difference between the groups (only the group managed through iniltration required rescue medications), but the iniltration group had a lower perception of pain. Conclusions: This study reported the same eficacy of preventive treatment of postoperative pain in patients who underwent radical mastectomy for instillation and iniltration with 7.5% ropivacaine and little need for rescue medication postoperatively.

Comparison Of Postoperative Stability Of Three Rigid Internal Fixation Techniques After Sagittal Split Ramus Osteotomy For Mandibular Advancement.

The aim of this investigation was to compare the skeletal stability of three different rigid fixation methods after mandibular advancement. Fifty-five class II malocclusion patients treated with the use of bilateral sagittal split ramus osteotomy and mandibular advancement were selected for this retrospective study. Group 1 (n = 17) had miniplates with monocortical screws, Group 2 (n = 16) had bicortical screws and Group 3 (n = 22) had the osteotomy fixed by means of the hybrid technique. Cephalograms were taken preoperatively, 1 week within the postoperative care period, and 6 months after the orthognathic surgery. Linear and angular changes of the cephalometric landmarks of the chin region were measured at each period, and the changes at each cephalometric landmark were determined for the time gaps. Postoperative changes in the mandibular shape were analyzed to determine the stability of fixation methods. There was minimum difference in the relapse of the mandibular advancement among the three groups. Statistical analysis showed no significant difference in postoperative stability. However, a positive correlation between the amount of advancement and the amount of postoperative relapse was demonstrated by the linear multiple regression test (p < 0.05). It can be concluded that all techniques can be used to obtain stable postoperative results in mandibular advancement after 6 months.

Long-term Postoperative Atrophy Of Contralateral Hippocampus And Cognitive Function In Unilateral Refractory Mtle With Unilateral Hippocampal Sclerosis.

This study aimed to evaluate long-term atrophy in contralateral hippocampal volume after surgery for unilateral MTLE, as well as the cognitive outcome for patients submitted to either selective transsylvian amygdalohippocampectomy (SelAH) or anterior temporal lobe resection (ATL). We performed a longitudinal study of 47 patients with MRI signs of unilateral hippocampal sclerosis (23 patients with right-sided hippocampal sclerosis) who underwent surgical treatment for MTLE. They underwent preoperative/postoperative high-resolution MRI as well as neuropsychological assessment for memory and estimated IQ. To investigate possible changes in the contralateral hippocampus of patients, we included 28 controls who underwent two MRIs at long-term intervals. The volumetry using preoperative MRI showed significant hippocampal atrophy ipsilateral to the side of surgery when compared with controls (p<0.0001) but no differences in contralateral hippocampal volumes. The mean postoperative follow-up was 8.7 years (± 2.5 SD; median=8.0). Our patients were classified as Engel I (80%), Engel II (18.2%), and Engel III (1.8%). We observed a small but significant reduction in the contralateral hippocampus of patients but no volume changes in controls. Most of the patients presented small declines in both estimated IQ and memory, which were more pronounced in patients with left TLE and in those with persistent seizures. Different surgical approaches did not impose differences in seizure control or in cognitive outcome. We observed small declines in cognitive scores with most of these patients, which were worse in patients with left-sided resection and in those who continued to suffer from postoperative seizures. We also demonstrated that manual volumetry can reveal a reduction in volume in the contralateral hippocampus, although this change was mild and could not be detected by visual analysis. These new findings suggest that dynamic processes continue to act after the removal of the hippocampus, and further studies with larger groups may help in understanding the underlying mechanisms.

Comment On 'practical Advice For Avoidance Of Pain Associated With Insertion Of Intrauterine Contraceptives': Authors' Response.

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Mastication Movements And Sleep Quality Of Patients With Myofascial Pain: Occlusal Device Therapy Improvements.

Patients with myofascial pain experience impaired mastication, which might also interfere with their sleep quality. The purpose of this study was to evaluate the jaw motion and sleep quality of patients with myofascial pain and the impact of a stabilization device therapy on both parameters. Fifty women diagnosed with myofascial pain by the Research Diagnostic Criteria were enrolled. Pain levels (visual analog scale), jaw movements (kinesiography), and sleep quality (Epworth Sleepiness Scale; Pittsburgh Sleep Quality Index) were evaluated before (control) and after stabilization device use. Range of motion (maximum opening, right and left excursions, and protrusion) and masticatory movements during Optosil mastication (opening, closing, and total cycle time; opening and closing angles; and maximum velocity) also were evaluated. Repeated-measures analysis of variance in a generalized linear mixed models procedure was used for statistical analysis (α=.05). At baseline, participants with myofascial pain showed a reduced range of jaw motion and poorer sleep quality. Treatment with a stabilization device reduced pain (P<.001) and increased both mouth opening (P<.001) and anteroposterior movement (P=.01). Also, after treatment, the maximum opening (P<.001) and closing (P=.04) velocities during mastication increased, and improvements in sleep scores for the Pittsburgh Sleep Quality Index (P<.001) and Epworth Sleepiness Scale (P=.04) were found. Myofascial pain impairs jaw motion and quality of sleep; the reduction of pain after the use of a stabilization device improves the range of motion and sleep parameters.

Pain Threshold And Sleep Quality In Women With Endometriosis.

Pain is a common complaint in women with endometriosis and can be influenced by many variables, including sleep disorders; however, no data are available on the sleep quality of women with endometriosis or on the correlation between sleep quality and pain. The 510 volunteers included in this study were divided into two groups: 257 women with a laparoscopic and histopathological diagnosis of endometriosis and 253 women with no history of endometriosis and no endometriosis-related symptoms. The volunteers answered two questionnaires: the Post-Sleep Inventory to evaluate sleep quality and the International Physical Activity Questionnaire to assess their level of physical activity. Pain was evaluated using a visual analogue scale (VAS) and women were also submitted to a physical examination, during which their pain threshold was assessed at 20 different body sites. Sleep quality was significantly poorer in women with endometriosis compared to women without the disease. The pain threshold was significantly lower in the greater trochanter and abdomen in women with endometriosis when compared to women without the disease; however, there was no difference in VAS pain score between the groups. The higher the VAS pain score, the lower the Post-Sleep Inventory score. Additionally, there was a significant positive correlation between the pain threshold at some body sites and sleep quality. Sleep quality was poorer and the pain threshold at certain body sites was lower in the group of women with endometriosis.