Acute pain management: operative or medical procedures and trauma

CD304 + adipose tissue-derived mesenchymal stem cell abundance in autologous fat grafts highly correlates with improvement of localized pain syndromes

ABSTRACT

Surgery, burns or surgery-free accident are leading causes of scars with altered tissue consistency, a reduced degree of motion and pain. Autologous fat grafting can dramatically improve tissue consistency and elasticity but less frequently results in the reduction of pain. Therefore, we analyzed different cell populations present within the adipose tissue to be engrafted and correlated them with the reduction of pain after surgery. Here, we identify a population of CD3 - CD4 - CD304 + cells present in grafted adipose tissue, whose abundance highly correlates with pain improvement shortly after surgery ( r2 = 0.7243****) as well as persistently over time (3 months later: r2 = 0.6277****, 1 year later: r2 = 0.5346***, and 4 years later: r2 = 0.5223***). These cells are characterized by the absence of the hematopoietic marker CD45, whereas they express CD90 and CD34, which characterize mesenchymal stem cells (MSCs); the concomitant presence of CD10 and CD73 in the plasma membrane supports a function of these cells in pain reduction. We deduce that the enrichment of this adipose tissue-derived MSC subset could enhance the therapeutic properties of adipose grafts and ameliorate localized pain syndromes.

Efficacy and Safety of Methylprednisolone for Lung Surgery: a Systematic Review and Meta-analysis of Randomized Controlled Trials

INTRODUCTION

The administration of methylprednisolone (MP) is a component of perioperative multimodal analgesia that mitigates the potentially deleterious effects of postoperative pain and opioid consumption. However, a systematic evaluation of the efficacy and safety of MP is lacking. The present systematic review and meta-analysis was performed to quantify the potential clinical benefits and risks of perioperative MP in lung surgery.

METHODS

We searched seven electronic databases for randomized controlled trials (RCTs) comparing MP with placebo. Coprimary outcomes were rest pain scores, dynamic pain scores, and cumulative morphine equivalent consumption within 24 h postoperatively.

RESULTS

A total of 11 trials including 643 participants were selected for our meta-analysis. The results demonstrated that the MP group had a significant difference in coprimary outcomes (rest pain scores, dynamic pain scores, and cumulative morphine equivalent consumption) compared with the placebo group; nevertheless, the improvement was not clinically meaningful based on minimum clinically important differences (MCID). Notably, MP administration reduced serum levels of interleukin (IL)-6 at 6 h (weighted mean difference -20.49 pg/mL; 95% CI -29.94 to -11.04), and decreased the incidence rate of acute lung injury (rate ratio 0.18; 95% CI 0.03-0.98) and cognitive dysfunction (rate ratio 0.43; 95% CI 0.21-0.88) compared with the placebo group.

CONCLUSIONS

Our findings suggest that the administration of MP contributed to an insignificant relief in acute postoperative pain for lung surgery in a clinical setting. Future studies should focus on exploring the role of MP in reducing pulmonary and surgical-related complications after lung surgery.

CLINICAL TRIAL NUMBER

PROSPERO registration number CRD42022314224.

Study protocol: hypnosis versus standard care for shoulder dislocation reduction in the emergency department - a multicentre, randomised, controlled study protocol

INTRODUCTION

Anterior shoulder dislocation is a common reason for consultation at the emergency department (ED). Hypnosis could be a safe and effective alternative therapy for pain relief during shoulder dislocation reduction but nowadays, evidence is not sufficient. The main objective of this study is to show that reduction under hypnosis is associated with a decrease in the use of analgesic compared with usual care.

METHODS AND ANALYSIS

We will conduct an interventional, controlled, multicentre, randomised study. A total of 44 patients with shoulder dislocation will be randomised in two groups: the hypnosis group (N=22) and the usual care group (N=22). The primary endpoint will be the comparison of morphine equivalent analgesic consumption during a shoulder dislocation reduction manoeuvre. Secondary endpoints will include haemodynamic parameters monitoring, patient and practitioner satisfaction using a Likert scale, use of coanalgesic or sedative drugs, number of reduction attempts and time spent at ED. Adverse events will be recorded. Statistical analysis will include parametric tests, multivariate linear regression and descriptive statistics.

ETHICS AND DISSEMINATION

This study has received ethics approval from the Comité de Protection des Personnes of Sud-Est IV on 03/11/2021 (ANSM informed on 19 November 2021). The results will be published in scientific articles and communicated in national and international conferences.

TRIAL REGISTRATION NUMBER

ClinicalTrial.gov: NCT04992598; National Clinical trial no ID RCB : 2021-A01382-39.

Pronounced Declines in Meperidine in the US: Is the End Imminent?

Background: Once a widely used analgesic in the United States (US), meperidine offered an alternative opioid to other opioids as a pain reliever and was widely assumed to be safer with acute pancreatitis. However, within the last two decades meperidine, has gone from a frequently used drug to being used only when patients exhibit atypical reactions to opioids (e.g., morphine and hydromorphone), to being taken off the World Health Organization List of Essential Medications and receiving strong recommendations for overall avoidance. The aim of this study was to identify changes in meperidine distribution in the US, and regional disparities as reported to the Drug Enforcement Administration’s Automation of Reports and Consolidated Orders System (DEA ARCOS) and Medicaid. Methods: Data related to meperidine distribution was obtained through ARCOS (2001−2021) and Medicaid public use files (2016−2021). Heat maps were used to visualize regional disparities in distribution by state. States outside a 95% confidence interval were statistically significant. Results: Meperidine distribution between 2001 and 2021 decreased by 97.4% (R = −0.97, p < 0.0001). There was a 34-fold state-level difference in meperidine distribution between Arkansas (16.8 mg/10 persons) and Connecticut (0.5 mg/10 persons) in 2020. Meperidine distribution in 2020 was elevated in Arkansas, Mississippi, and Alabama. In 2021, meperidine distribution was highest in Arkansas (16.7 mg/10 persons) and lowest in Connecticut (0.8 mg/10 persons). Total prescriptions of meperidine as reported by Medicaid decreased by 73.8% (R = −0.67, p = 0.045) between 2016 and 2021. Conclusion: We observed a decrease in the overall distribution of meperidine in the past two decades, with a similar recent decline in prescribing it to Medicaid enrollees. The shortage of some parenteral formulations is an important contributor to these declines, however, the most likely explanation for this global decline in use is related to an increased recognition of safety concerns related to important drug interactions and a neurotoxic metabolite. This data may reflect plans to phase out the use of this opioid, especially in the many situations where safer and more preferred opioids are available.

Clinical and pathological aspects of condyloma acuminatum - review of literature and case presentation

Condyloma acuminatum (CA) is a pathology caused by the human papillomavirus (HPV). It is manifested by the appearance of warts in the vulvar, pubic, and anorectal regions, but can occur in other areas. It is a common disease that can be prevented by using measures such as condoms or vaccine. Topical, local, pharmacological, surgical, and excisional therapy options are available for this pathology. Macroscopically, it appears as a vegetative tumor, with a single implantation base that branches towards the periphery, with a cauliflower appearance. CA is defined microscopically by acanthosis, parakeratosis, papillomatosis and koilocytosis. Immunohistochemical studies can detect the presence of various HPV strains or viral antigens and can emphasize certain specific characteristics; e.g., in the case presented in this study, we observed that the tumor had a fulminant evolution due to a strong vascular base identified with anti-cluster of differentiation (CD) 34 antibody, by the existence of epithelial cells with a high degree of cell proliferation, as evidenced by the anti-Ki67 antibody, the inactivation of the tumor suppressor gene and the appearance of immunolabeling for the anti-p53 antibody, by the strong immunoreactivity for p63 which reveals the existence of cells with dysplastic and neoplastic transformation potential, but also by detecting the immunolabeling for p16^INK4a that is associated with the existence of HPV. Also, the tumor was immunoreactive for cytokeratin (CK) AE1/AE3, partially immunoreactive for CK5/6 in the basal layer and negative for CK7, which demonstrates the squamous epithelial origin of the described tumor. Subepithelial cells of the inflammatory system have been identified, such as macrophages immunolabeled with anti-CD68 antibody, T-lymphocytes immunolabeled with anti-CD3 antibody and rare B-lymphocytes immunolabeled with anti-CD20 antibody, which demonstrates the strong cellular response to remove the virus from the structure. Surgical and excisional treatment was helpful for the patient, because she was able to resume normal sexual activity and defecation, and on the other hand, microscopic studies showed the potential for malignant transformation of CA.

Incidence of Inadequate Pain Treatment among Ventilated, Critically Ill Surgical Patients in a Thai Population

BACKGROUND

Inadequate pain treatment during intensive care unit stays causes many unfavorable outcomes. Pain assessment in mechanically ventilated patients is challenging because most cannot self-report pain. The incidence of pain among Thai surgical intensive care unit (SICU) patients has never been reported.

AIMS

To determine the inadequate pain control incidence among ventilated, critically ill, surgical patients.

DESIGN

Prospective, observational study.

SETTING

SICU of a university-based hospital during November 2017-January 2019.

PARTICIPANTS

Patients aged > 18 years, admitted to the SICU for a foreseeable duration of mechanical ventilation > 24 hours were included.

METHODS

On post-admission Day 2, each was assessed for pain at rest (every 4 hours) and during bed-bathing using the Critical Care Pain Observation Tool (CPOT; Thai version) or the 0-10 numeric rating scale (NRS). CPOT scores > 2 or NRS scores > 3 signified inadequate pain control, while a RASS score ≤ -3 was defined as overtreatment.

RESULTS

118 were included. The inadequate-pain-management incidence was 34% (n = 40) at rest and 29% (n = 34) during bed-bathing. The severe-pain incidence (NRS > 6, or CPOT > 5) was 5.9% (n = 7). Our incidence of overtreatment was 1.7%. The demographic data and ICU complication-rates of patients with adequate and inadequate pain treatment were similar.

CONCLUSIONS

Pain assessment tools in critically ill patients should be developed and validated to the language of the tool users in order to determine the incidence of pain accurately. The inadequate-pain-treatment incidence in ventilated critically ill, Thai surgical patients was lower than previously reported from other countries.

Adaptation of the Multidimensional Pain Evaluation Scale: A Cross-Cultural Study

BACKGROUND AND PURPOSE

Instruments to measure pain must be cross-culturally adapted through rigorous processes, so they can provide equivalence of measure regardless of the context in which they are applied. The study aim was to perform a cross-cultural adaptation of Multidimensional Pain Evaluation Scale (MPES) for use in the United States.

METHODS

Cross-cultural adaptation study entailed translation, back translation, and review by a committee, face and content validity and pilot testing with 90 participants with acute or chronic pain from United States. The Cronbach's alpha coefficient was calculated.

RESULTS

Some items of MPES was changed to maintain the highest level of similarity between the original scales in Portuguese and adapted to English.

CONCLUSION

The Cronbach's alpha was high showed this scale has internal consistency and reliability.

Trend and Economic Burden of Intravenous Narcotic Analgesic Utilization in Major Vascular Interventions in the United States

BACKGROUND

The use of IV narcotic analgesics (IVNA) within the context of vascular procedures is not fully described. We sought to evaluate the burden of IVNA including narcotic analgesia-related adverse drug events (NARADE), associated mortality and hospitalization cost in open and endovascular vascular procedures, and to compare it with nonnarcotic analgesia (IVNNA).

METHODS

Retrospective cross-sectional study in hospitals participating in Premier database (2009-2015). Logistic regression analysis was implemented to report the risks of NARADE and in-hospital mortality. Negative binomial regression was used to assess length of stay and generalized linear modeling was used to estimate the hospitalization cost.

RESULTS

A total of 171,473 patients were identified. NARADE occurred in 6.2% of the cohort. NARADE group was similar in gender and race but was slightly older (median age 71 vs. 70; P < 0.001). After risk-adjustment, NARADE risk was higher in patients who received IVNA-alone in carotid and lower extremity revascularization (LER) [OR (odds ratio) (95% confidence interval [CI]): 1.17 (1.02-1.34) and 1.31 (1.14-1.50)] or combined with IVNNA [OR (95% CI): 1.34 (1.13-1.59) and 1.81 (1.54-2.13)], respectively. Patients receiving aortic repair benefited from the use of IVNA + IVNNA [OR (95% CI): 0.82 (0.69-0.98)]. Occurrence of NARADE doubled the LOS, amplified mortality risk and increased cost in all domains. NARADE increased the odds of mortality by 24.3, 6.5 (4.9-8.68) and 16.6 times and added $5,368, $12,737 and $11,349 to the cost of carotid, aortic and LER interventions, respectively. In contrast, IVNNA was not associated with NARADE risk, increased LOS or cost and showed a survival benefit in patients undergoing open aortic repair [aOR (95% CI): 0.52 (0.36-0.75)].

CONCLUSIONS AND RELEVANCE

The use of opioid-based narcotics had increased the risk of NARADE, resources utilization and NARADE-related mortality. Yet the use of nonopioid-based analgesic was safe, did not increase the cost and reduced mortality in open AA repair. This entices shifting the paradigm toward exploring nonopioid-based analgesia options in order to replace or minimize opioid requirements.

Device-Related Error in Patient-Controlled Analgesia: Analysis of 82,698 Patients in a Tertiary Hospital

BACKGROUND

Patient-controlled analgesia (PCA) is one of the most popular and effective methods for managing postoperative pain. Various types of continuous infusion pumps are available for the safe and accurate administration of analgesic drugs. Here we report the causes and clinical outcomes of device-related errors in PCA.

METHODS

Clinical records from January 1, 2011 to December 31, 2014 were collected by acute pain service team nurses in a 2715-bed tertiary hospital. Devices for all types of PCA, including intravenous PCA, epidural PCA, and nerve block PCA, were included for analysis. The following 4 types of infusion pumps were used during the study period: elastomeric balloon infusers, carbon dioxide-driven infusers, semielectronic disposable pumps, and electronic programmable pumps. We categorized PCA device-related errors based on the error mechanism and clinical features.

RESULTS

Among 82,698 surgical patients using PCA, 610 cases (0.74%) were reported as human error, and 155 cases (0.19%) of device-related errors were noted during the 4-year study period. The most common type of device-related error was underflow, which was observed in 47 cases (30.3%). The electronic programmable pump exhibited the high incidence of errors in PCA (70 of 15,052 patients; 0.47%; 95% confidence interval, 0.36-0.59) among the 4 types of devices, and 96 of 152 (63%) patients experienced some type of adverse outcome, ranging from minor symptoms to respiratory arrest.

CONCLUSIONS

The incidence of PCA device-related errors was <0.2% and significantly differed according to the infusion pump type. A total of 63% of patients with PCA device-related errors suffered from adverse clinical outcomes, with no mortality. Recent technological advances may contribute to reducing the incidence and severity of PCA errors. Nonetheless, the results of this study can be used to improve patient safety and ensure quality care.

How effective is periarticular drug infiltration in providing pain relief and early functional outcome following total hip arthroplasty?

The aim of the study was to compare the efficacy of periarticular injection of a cocktail of analgesic drugs (PIC) with epidural infiltration (EA), in providing postoperative pain relief and early functional improvement following Total Hip Arthroplasty (THA).

METHODS

50 patients undergoing unilateral THA were randomized to receive either EA or PIC for postoperative pain control. Postoperative pain relief, as determined by the visual analogue scale (VAS), functional recovery and side effects related to EA and PIC were assessed.

RESULTS

PIC resulted in significantly lower VAS scores [0.48(0.71) vs 3.04(2.07)] in the first 24 h after surgery [mean (SD)], when compared to EA. The pain relief continued to be significantly lower even on the 10th postoperative day. Functional recovery was significantly better in the PIC group, with patients being able to walk longer distances and climb steps more quickly following THA. EA, unlike PIC was associated with side effects like nausea, vomiting, motor weakness, back pain and urinary retention. The overall satisfaction rate with treatment was significantly better in PIC group (9.04/10) than those who received EA (7.76/10).

CONCLUSION

PIC provides significantly better pain control and functional recovery in the early postoperative period, with less side effects when compared with EA. PIC should be the choice for pain control following THA.

ON-Q infusion pump linked to increased hospital stay after total knee arthroplasty

Purpose

The purpose of this study was to evaluate immediate postoperative pain control modalities after total knee arthroplasty at the author's specific institution and compare those modalities with patient satisfaction, rehabilitation status, and length of hospital stay.

Methods

A retrospective chart review of 101 patients who underwent total knee arthroplasty from 2013 to 2016 was performed. Data was collected including the pain control modality, total pain medication consumption, physical therapy progress, length of hospital stay and Visual Analog Scores. Analysis was then performed using SAS proprietary software. Results were reported as statistically significant if p value was less than 0.05.

Results

Multiple variables proved to be statistically significant (p value <0.05) in this particular study. Patients who received Valium required more morphine equivalents on average and reported higher Visual Analog Scores (VAS). For those patients who received a lower extremity nerve block pre operatively, there was a decrease in morphine equivalents on postoperative day one and lower VAS. For those patients who received the continuous pain pump, ON-Q postoperatively, there was an average increase in length of hospital stay by one day and a decrease in ambulation on postoperative day one. Also, females required less overall pain medication on postoperative days two and three compared to their male counterparts. Finally, there was no statistically significant difference for those patients who received Lyrica (pregabalin) or NSAIDS for the parameters that were measured in this study.

Conclusions

Postoperative pain control modalities after total knee arthroplasty are highly variable among physicians. This variability has allowed researchers to review each modality and compare and contrast the benefits with the potential adverse effects of these medications on total knee replacement outcomes. The data in this study suggests that the use of Valium is correlated with increased pain medication consumption and decreased patient satisfaction. Data from this study also reveals that patients who underwent preoperative nerve blocks experienced decreased pain on postoperative day one and greater patient satisfaction. The most notable contribution of this study was the discovery of the adverse effects of the continuous pain pump, ON-Q. Patients treated with this modality had decreased ambulation on postoperative day one and on average remained in the hospital one extra day, a variable that significantly increases the cost of a total knee arthroplasty for the hospital, the surgeon and the patient. Even though this data is significant, further studies should be performed to enhance our knowledge of postoperative pain control for these patients.

Do patient perceptions of provider communication relate to experiences of physical pain?

OBJECTIVES

Patient-provider communication is an important component of the medical interaction yet little research has examined the relationships between perceptions of communication and health outcomes or the mechanisms by which communication may ameliorate the pain experience. This is the first study to examine the relationships between patients' perceptions of provider communication, pain intensity and self-efficacy for managing chronic disease.

METHODS

The total sample contained 1027 (85.8% male) Veteran patients. Patients responded to surveys about their experiences and outcomes of care, including measures of patient-provider communication, self-efficacy and pain outcomes including pain intensity and pain interference.

RESULTS

Results showed more positive perceptions of provider communication were related to lower levels of pain intensity and pain interference and that this relationship was significantly mediated by higher levels of self-efficacy for managing chronic disease.

CONCLUSION

More positive provider communication was related to higher levels of self-efficacy, which in turn was related to lower levels of pain intensity and pain interference. Findings suggest that providers may be able to elicit higher levels of self-efficacy in their patients by providing patient-centered communication, which in turn will reduce pain intensity and interference in their patient's lives.

Prescription Opioid Exposures Among Children and Adolescents in the United States: 2000-2015

OBJECTIVES

This study analyzes and compares exposures to prescription opioids among children and adolescents younger than 20 years old in the United States.

METHODS

Data from the National Poison Data System for 2000 through 2015 were analyzed.

RESULTS

Poison control centers received reports of 188 468 prescription opioid exposures among children aged <20 years old from 2000 through 2015. The annual number and rate of exposures increased early in the study period, but declined after 2009, except for buprenorphine exposures, which increased during the last 3 study years. Hydrocodone accounted for the largest proportion of exposures (28.7%), and 47.1% of children exposed to buprenorphine were admitted to a health care facility (HCF). The odds of being admitted to an HCF were higher for teenagers than for children aged 0 to 5 years (odds ratio [OR]: 2.86; 95% confidence interval [CI]: 2.78-2.94) or children aged 6 to 12 years (OR: 6.62; 95% CI: 6.06-7.02). Teenagers also had greater odds of serious medical outcomes than did children aged 0 to 5 years (OR: 3.03; 95% CI: 2.92-3.15) or children aged 6 to 12 years (OR: 4.59; 95% CI: 4.21-5.00). The rate of prescription opioid-related suspected suicides among teenagers increased by 52.7% during the study period.

CONCLUSIONS

Prescription opioid-related HCF admissions and serious medical outcomes were higher among teenagers. Contrary to trends for other prescription opioids, exposures to buprenorphine have increased in recent years; children aged 0 to 5 years accounted for almost 90% of buprenorphine exposures. These findings indicate that additional prevention efforts are needed.

Acute Pain Management

Acute pain management is improving steadily over the past few years, but training and professional education are still lacking in many professions. Untreated or undertreated acute pain could have detrimental effects on the patient in terms of comfort and recovery from trauma or surgery. Acute undertreated pain can decrease a patient's vascular perfusion, increase oxygen demand, suppress the immune system, and possibly risk increased incidence of venous thrombosis. Although acute postoperative pain needs to be managed aggressively, patients are most vulnerable during this period for developing adverse effects, and therefore, patient assessment and careful drug therapy evaluation are necessary processes in therapeutic planning. Acute pain management requires careful and thorough initial assessment and follow-up reassessment in addition to frequent dosage adjustments, and managing analgesic induced side effects. Analgesic selection and dosing must be based on the patient's past and recent analgesic exposure. There is no single acute pain management regimen that is suitable for all patients. Analgesics must be tailored to the individual patient.

IV acetaminophen: Efficacy of a single dose for postoperative pain after hip arthroplasty: subset data analysis of 2 unpublished randomized clinical trials

Inadequate control of postoperative pain after orthopedic procedures may trigger complications that increase morbidity. Multimodal analgesia is used to manage pain effectively after surgical procedures and reduce the need for rescue analgesia. Intravenous (IV) acetaminophen (OFIRMEV; Cadence Pharmaceuticals, Inc.), an analgesic that has been studied and used in the multimodal management of acute pain after major orthopedic procedures, combines the safety seen with oral and rectal formulations with a preferred route of administration. Two double-blind, randomized, placebo-controlled clinical trials were conducted (total 130 patients) to determine the efficacy and safety of single-dose IV acetaminophen in patients following total hip arthroplasty. Although both studies were stopped prematurely, overlap in patient populations, study design, and methodologies in the single-dose phase of these studies allowed for analysis of their results to be presented concurrently. Both trials demonstrated IV acetaminophen having greater efficacy than placebo in terms of primary endpoints [pain intensity differences from T0.5 to T3 (P < 0.05 in both studies)]. The use of IV acetaminophen also reduced the need for rescue opioid consumption, with patients receiving IV acetaminophen consuming, on average, less than half the amount of rescue medication as those receiving placebo. IV acetaminophen was effective in treating moderate-to-severe pain after total hip arthroplasty and reduced the need for rescue opioid consumption.

Multimodal pain management in total knee arthroplasty: a prospective randomized controlled trial

We analyze the effects of a multimodal analgesic regimen on postoperative pain, function, adverse effects and satisfaction compared to patient-controlled analgesia (PCA). Thirty-six patients undergoing TKA were randomized to receive either (1) periarticular injection before wound closure (30cc 0.5% bupivacaine, 10mg MSO4, 15 mg ketorolac) and multimodal analgesics (oxycodone, tramadol, ketorolac; narcotics as needed) or (2) hydromorphone PCA. Preoperative and postoperative data were collected for VAS pain scores, time to physical therapy milestones, hospital stay length, patient satisfaction, narcotic consumption and medication-related adverse effects. The multimodal group had lower VAS scores, fewer adverse effects, lower narcotic usage, higher satisfaction scores and earlier times to physical therapy milestones. Multimodal pain management protocol decreases narcotic usage, improves pain scores, increases satisfaction and enhances early recovery.

CYP2D6*2 Polymorphism as a Predictor of Failed Outpatient Tramadol Therapy in Postherpetic Neuralgia Patients

Human cytochrome P4502D6 (CYP2D6) gene is highly polymorphic, leading to wide interindividual ethnic differences in CYP2D6-mediated drug metabolism. Its activity ranges from complete deficiency to excessive activity, potentially causing toxicity of the medication or therapeutic failure with recommended drug dosages. The aim of the study was to find the association of CYP2D6*2 polymorphisms with demographic characters (age, sex, and weight), pain intensity scales [numerical rating scale (NRS) sleep, global perceived effect (GPE)], and adverse drug effects in postherpetic neuralgia (PHN) patients receiving tramadol. The study comprised 246 patients [including 123 nonresponders (NRs) and 123 responders (Rs)] with PHN undergoing analgesic treatment at the pain clinic, Out Patient Department, University College of Medical Sciences, Guru Teg Bahadur Hospital, Delhi, India. Patients with any history of diabetes mellitus, human immunodeficiency virus, malignancy, hematological or liver disease, psychiatric illness, alcohol abuse, and tramadol sensitivity were excluded from the study. The NRSs of (resting and movement), NRS-sleep, and GPE were evaluated by the treating physician. Adverse drug effects during the time of the study were recorded. All samples were analyzed for CYP2D6*2 polymorphism using the polymerase chain reaction-restriction fragment length polymorphism method. The genotype distribution did not vary significantly among genders [NR (P = 0.723); R (P = 0.947)] and different age groups in NRs (P = 0.763) and Rs (P = 0.268). Clinically, statistically significant (P < 0.001) results were obtained in both the groups when compared with baseline in the NRS-sleep and GPE scores, whereas no association was found between NRS-sleep and GPE scores when compared with CYP2D6*2 genotype (P > 0.05). In addition, CYP2D6*2 genotype was not related to the adverse effects of analgesic therapy. The overall results suggested that CYP2D6*2 polymorphism plays no role in the PHN patients receiving tramadol treatment. The CYP2D6*2 polymorphism may not be a predictor of treatment outcome of patients with respect to PHN-receiving tramadol.

Guidelines for the management of postoperative pain after total knee arthroplasty

This clinical practice guideline was approved by Korean Knee Society on February 28, 2012. It is based on a systematic review of published studies on the management of postoperative pain after total knee arthroplasty and was developed to include the overall pain management modalities. The purpose of the guideline is to help improve treatment based on current best evidence. Eleven recommendations have been developed based on a systematic review of research evidence and the consensus opinions of a multidisciplinary working group of experts. These recommendations will be revised regularly following systematic review of new research evidence as this becomes available.

CYP2D6*4 polymorphism, tramadol treatment and its clinical impact in patients with postherpetic neuralgia

Aim: The aim of this study was to investigate the associations between the CYP2D6*4 polymorphism, interindividual differences in CYP2D6 activity and adverse drug effects in postherpetic neuralgia (PHN) patients receiving tramadol. Patients & methods: The study comprised 158 patients (including 78 nonresponders and 80 responders) with PHN who were undergoing analgesic treatment at the Pain Clinic in the Out Patient Department of the University College of Medical Sciences, Guru Teg Bahadur Hospital (New Delhi, India). The numerical rating scale scores were measured at the resting and movement stages; Neuropathic Pain Symptom Inventory scores were evaluated by the treating physician. WHO-brief questionnaire scores for quality of life and adverse drug effects during the time of study were recorded. All samples were analyzed for the CYP2D6*4 polymorphism using the PCR-restriction fragmentation length polymorphism method. Results: The genotype distribution did not vary significantly among different age groups in nonresponders and responders. The CYP2D6*4 polymorphism was significantly associated with lower Neuropathic Pain Symptom Inventory (burning, squeezing stabbing and pressure) scores. The quality-of-life (sociological, psychological and environmental domains) scores correlated with CYP2D6*4 and showed significant results (p < 0.05) using a generalized linear model. No association was found between the physiological domain compared with the CYP2D6*4 allele (p > 0.05). In addition, the homozygous mutated CYP2D6*4 allele was not related to adverse effects of analgesic therapy. Conclusion: The CYP2D6*4 polymorphism may not be a predictor for treatment outcome of patients with PHN receiving tramadol. However, further investigation is required to confirm these findings in a larger sample size.

Pain management after total knee arthroplasty using a multimodal approach

Improvements in pain management techniques over the past decade have had a significant impact on the outcomes of total knee arthroplasty. Of these techniques, multimodal approaches have shown potential. The purpose of this study was to compare the results of periarticular injection (PAI) to a combination of patient-controlled epidural analgesia and femoral nerve block (PCEA/FNB). Ninety patients undergoing primary unilateral total knee arthroplasty between June 2010 and March 2011 were randomized into 2 groups. The first group received the PCEA/FNB protocol, whereas the second group received the PAI. Mean patient age was 66.1 ± 8.7 years. All patients were operated on using a similar standard medial parapatellar approach, and all received preemptive analgesia and postoperative pain protocols. All patients were interviewed twice daily for the first 3 days postoperatively, once on day 7, and once in month 6. The 2 groups had similar readiness for discharge (PCEA/FNB group, 3.3 ± 1.2 days; PAI group, 3.2 ± 1.9 days). The results indicated no statistical difference between the 2 groups in 3 of 4 categories (rest in the morning, rest in the evening, and ambulation in the morning). Pain on ambulation was the only category that was statistically lower in the PCEA/FNB group than in the PAI group.Although the study demonstrates similar results between the 2 groups, PAI can play a major role in postoperative pain control in institutions that may not have appropriately trained individuals, equipment, and resources for PCEA/FNB. It also reduces many of the side effects and complications associated with regional anesthesia.

Efficacy of multimodal pain control protocol in the setting of total hip arthroplasty

BACKGROUND

This study evaluated the benefits and safety of a multimodal pain control protocol, which included a periarticular injection of local anesthetics, in patients undergoing total hip arthroplasty.

METHODS

Between March 2006 and March 2007, 60 patients undergoing unilateral total hip arthroplasty were randomized to undergo either a multimodal pain control protocol or a conventional pain control protocol. The following parameters were compared: the preoperative and postoperative visual analogue scales (VAS), hospital stay, operative time, postoperative rehabilitation, additional painkiller consumption, and complication rates.

RESULTS

There was no difference between the groups in terms of diagnosis, age, gender, and BMI. Although both groups had similar VAS scores in the preoperative period and on the fifth postoperative day, there was a significant difference between the groups over the four-day period after surgery. There were no differences in the hospital stay, operative time, additional painkiller consumption, or complication rate between the groups. The average time for comfortable crutch ambulation was 2.8 days in the multimodal pain control protocol group and 5.3 days in the control group.

CONCLUSIONS

The multimodal pain control protocol can significantly reduce the level of postoperative pain and improve patients' satisfaction, with no apparent risks, after total hip arthroplasty.

Multimodal pain management after total hip and knee arthroplasty at the Ranawat Orthopaedic Center

Improvements in pain management techniques in the last decade have had a major impact on the practice of total hip and knee arthroplasty (THA and TKA). Although there are a number of treatment options for postoperative pain, a gold standard has not been established. However, there appears to be a shift towards multimodal approaches using regional anesthesia to minimize narcotic consumption and to avoid narcotic-related side effects. Over the last 10 years, we have used intravenous patient-controlled analgesia (PCA), femoral nerve block (FNB), and continuous epidural infusions for 24 and 48 hours with and without FNB. Unfortunately, all of these techniques had shortcomings, not the least of which was suboptimal pain control and unwanted side effects. Our practice has currently evolved to using a multimodal protocol that emphasizes local periarticular injections while minimizing the use of parenteral narcotics. Multimodal protocols after THA and TKA have been a substantial advance; they provide better pain control and patient satisfaction, lower overall narcotic consumption, reduce hospital stay, and improve function while minimizing complications. Although no pain protocol is ideal, it is clear that patients should have optimum pain control after TKA and THA for enhanced satisfaction and function.

LEVEL OF EVIDENCE

Level V, expert opinion. See the Guidelines for Authors for a complete description of levels of evidence.

Impact of CYP2D6 genetic polymorphism on tramadol pharmacokinetics and pharmacodynamics

BACKGROUND AND OBJECTIVE

Tramadol is metabolized by the highly polymorphic enzyme cytochrome P450 (CYP)2D6. Patients with different CYP2D6 genotypes may respond differently to tramadol in terms of pain relief and adverse events. In this study, we compare the pharmacokinetics and effects of tramadol in Malaysian patients with different genotypes to establish the pharmacokinetic-pharmacodynamic relationship of tramadol.

STUDY DESIGN AND SETTING

All patients received an intravenous dose of tramadol 100mg as their first postoperative analgesic. Blood was sampled at 0 minutes and subsequently at 15 and 30 minutes, 1, 2, 4, 8, 16, 20, and 24 hours for serum tramadol and analyzed by high-performance liquid chromatography (HPLC). Patients were genotyped for CYP2D6*1, *3, *4, *5, *9, *10, and *17 alleles and duplication of the gene by means of an allele-specific PCR. Pain was measured using the Visual Analog Scales, and adverse effects were recorded.

RESULTS

About half of the patients had the wild-type allele (CYP2D6*1), with the 'Asian'CYP2D6*10 allele accounting for most of the rest (40%). None of the genotypes predicted poor metabolism. Twenty-seven percent of the patients were intermediate metabolizers (IM) and 2.9% were ultra-rapid (UM) metabolizers; the remaining 70% were extensive metabolizers (EM). The mean total clearance (CL) predicted by the model was lower (19 L/h) and the half-life longer (5.9 hours) than those reported in Western populations. This may due to the high frequency of the CYP2D6*10 allele amongst Malaysian patients. The UM and EM groups had 2.6- and 1.3-times faster CL, respectively, than the IM. CL was 16, 18, 23, and 42 L/h while mean half-lives were 7.1, 6.8, 5.6, and 3.8 hours among the IM, EM1, EM2, and UM groups, respectively. However, the analgesic effects of tramadol were not measured adequately among the postoperative patients to establish its full therapeutic effects. There were significant differences in the adverse-effect profiles amongst the various genotype groups, with the IM group experiencing more adverse effects than the EM, and the EM having more adverse effects than the UM.

CONCLUSION

CYP2D6 activity may play an important role in determining the pharmacokinetics of tramadol and in predicting its adverse effects. If these results can be confirmed in a larger population, genotyping may be an important tool in determining the dose of tramadol.

Controlling pain after total hip and knee arthroplasty using a multimodal protocol with local periarticular injections: a prospective randomized study

In this prospective randomized study, patients undergoing total hip (THA) or knee arthroplasty (TKA) were randomized to either a study group receiving periarticular injections or a control group receiving patient-controlled analgesia with or without femoral nerve block (TKA patients). All patients received a comprehensive multimodal perioperative protocol. Pain, recovery of functional milestones, and overall satisfaction were assessed. The THA study group demonstrated significantly lower average pain scores and higher overall satisfaction than the control group. There was no significant difference in pain scores between the study and control groups in the TKA cohort. Both study groups demonstrated lower narcotic usage and side effects as well as improved early functional recovery. Periarticular injection with a multimodal protocol was shown to safely provide excellent pain control and functional recovery and can be substituted for conventional pain control modalities.

Early oral analgesia after fast-track cardiac anesthesia

PURPOSE

Oral analgesia after "fast-track" cardiac anesthesia has not been explored. The aim of this study was to compare two oral oxycodone analgesic regimens.

METHODS

One hundred-twenty patients scheduled for coronary artery bypass grafting were randomly assigned postoperatively to receive immediate-release oxycodone 5 mg and acetaminophen 325 mg (Percocet-5) (group I) per os four times daily, or controlled-release oxycodone 10 mg (OxyContin) (group II) per os every 12 hr and placebo twice daily. Acetaminophen 500 mg per os was used as first-line rescue medication, and immediate-release oxycodone (syrup form) 5 mg per os as second-line rescue medication. Pain intensity was assessed with a visual analogue scale on the first postoperative day, the morning after extubation, and thereafter four times daily for four days. Use of rescue medication and adverse events were recorded.

RESULTS

Baseline demographic and operation-related characteristics were similar in both groups. While pain control was good in both groups, the immediate-release group experienced less pain on all postoperative days (P = 0.003), required significantly less rescue medication, and had fewer adverse effects such as somnolence and nausea.

CONCLUSION

Peroral oxycodone is effective for early pain control after fast-track cardiac anesthesia. Immediate-release oxycodone/ acetaminophen appears to provide better analgesia and fewer side effects compared to controlled-release oxycodone.

The management of acute dental pain in the recovering alcoholic

Although there have been many advances in our understanding of the neurophysiology of pain, the management of acute pain continues to be a challenge. When the need arises to provide adequate and effective pain management for the recovering alcoholic, the problem becomes much more complex. The clinician must provide the patient with adequate analgesia without causing a relapse. In the US, 6% to 10% of the population has attended Alcoholics Anonymous at some point, increasing the likelihood of the clinician being faced with the need to manage acute pain in a recovering alcoholic. The purpose of this article is to suggest guidelines for the management of acute dental pain in the recovering alcoholic based on current principles of acute pain management and for the treatment of pain in addicted patients.

Acute pain management after surgery or in the emergency room in Switzerland: a comparative survey of Swiss anaesthesiologists and surgeons

The treatment of acute pain remains unsatisfactory despite advances in pain research and the publication of numerous guidelines. The aim of this study was to survey postoperative and emergency room acute pain treatment in Switzerland, particularly regarding compliance with practice guidelines on therapeutic responsibility, treatment algorithms, pain documentation, quality control and education.A representative sample of anaesthesiologists and surgeons (general and orthopaedic) was selected from all Swiss hospitals with regular surgical activity and sent a 256 point questionnaire on acute pain management. Five hundred and seventy five doctors were contacted in 98 hospitals, 44% of doctors (covering 89% of hospitals) returned fully completed questionnaires. Half the respondents work in a hospital with an acute pain service. For postoperative pain management, only 10% of prescription is by algorithm, less than a third of respondents regularly determine pain scores, only 15% perform any statistical analysis of pain management, less than one third regularly meet to discuss management problems, and half claim not to have received-or be receiving-formal (i.e. structured/accredited) pain education. The situation is even less satisfactory for emergency room analgesia. Respondents accept the contribution of postoperative and emergency room analgesia to reduced costs and improved medical outcomes. Asked to highlight their major concerns in acute pain management, lack of education and inadequate organisation are listed in first and second positions. This survey suggests that compliance with published practice guidelines for acute pain management can be improved, and highlights the need for continuing organisational and educational development in acute analgesia, particularly for the emergency room.

Evaluation of an acute pain service

Implementation of an acute pain nurse role and the expansion of the Acute Pain Service (APS) at a newly merged Canadian hospital system led to an evaluation of these programs. A literature review of APSs showed that the services with an APS nurse had improved patient outcomes. As a result, a PACU nurse was added to the APS at all hospitals, and all services were restructured. Surveys conducted one year after this reorganization showed very positive response ratings in the areas of quality of care, but mixed results in other areas including education and job satisfaction. Flow diagrams for the clinical units were developed, and both structured and informal education sessions were provided. The description of the APS nurse's role was also redefined.

Pain relief in major trauma patients: an Israeli perspective

BACKGROUND

The pain of major trauma patients remains often unrelieved while in the emergency department. Our objective was to examine pain management in several trauma units, and to evaluate the impact of implementation of a trauma pain management protocol.

METHODS

Current status was evaluated from questionnaires filled by trauma unit personnel of nine medical centers. In one, a pain management protocol was introduced. Staff and patients evaluated pain management before and after the protocol was instituted.

RESULTS

About 80% of staff respondents from various centers were not aware of guidelines for pain management in trauma. The belief that pain assists diagnosis was the main reason (78.6%) for withholding analgesia. Large variability existed on what contraindicates analgesia, with the majority withholding analgesia in abdominal and multiple injuries. When administered, analgesia was delayed, and most commonly intramuscular meperidine was given. After the protocol's implementation, the personnel's awareness of analgesia increased, and consequently it was administered earlier and to more patients, mostly as intravenous morphine. Patients appreciated the timely analgesia (38% after vs. 14% before, p = 0.01), with fewer receiving none. Analgesia was considered beneficial by more patients (70% after vs. 23% before, p < 0.001), and enhanced cooperativity with personnel (p < 0.001). This was reflected in increased overall satisfaction with pain relief during the entire hospitalization.

CONCLUSION

The importance of pain management protocols in major trauma was demonstrated by the response of personnel and patients.

Reducing post-traumatic morbidity with pain management

Since significant pain can adversely affect multiple organ systems, many anesthesiologists believe that effective pain control can decrease perioperative and post-trauma morbidity. To achieve the goal of attenuating the physiological stress response associated with trauma, modalities such as patient-controlled analgesia, epidural infusions and peripheral nerve blocks are being utilized. This article will review the physiological response to pain, the new strategies and techniques for providing pain relief, and recent literature that evaluates the effect of the newer pain modalities on perioperative morbidity.