Perioperative medicine training resources: U6M2: Management of analgesics for discharged patients

Abstract
Background: High-dose opioid prescribing is associated with an increased risk of harms, including death.

Objective: The aim of this article is to discuss the concept of high-risk opioid prescribing, as well as relevant management strategies for patients on >100 mg oral morphine equivalent daily dose (OMEDD). The six 'Rs' approach to managing high-risk opioid prescribing (Rotation of opioids; Reduction; Replacement pharmacotherapy; Reversal with naloxone; Referral; Restriction of supply) is discussed.

Discussion: The six Rs is an aide-memoire that summarises the management options available to mitigate the risk of high OMEDDs. However, an effective therapeutic alliance between clinician and patient remains the foundation of all risk mitigation strategies.

Abstract
Neuropathic pain, caused by various central and peripheral nerve disorders, is especially problematic because of its severity, chronicity and resistance to simple analgesics. The condition affects 2%-3% of the population, is costly to the health care system and is personally devastating to the people who experience it. The diagnosis of neuropathic pain is based primarily on history (e.g., underlying disorder and distinct pain qualities) and the findings on physical examination (e.g., pattern of sensory disturbance); however, several tests may sometimes be helpful. Important pathophysiologic mechanisms include sodium-and calcium-channel upregulation, spinal hyperexcitability, descending facilitation and aberrant sympathetic-somatic nervous system interactions. Treatments are generally palliative and include conservative nonpharmacologic therapies, drugs and more invasive interventions (e.g., spinal cord stimulation). Individualizing treatment requires consideration of the functional impact of the neuropathic pain (e.g., depression, disability) as well as ongoing evaluation, patient education, reassurance and specialty referral. We propose a primary care algorithm for treatments with the most favourable risk-benefit profile, including topical lidocaine, gabapentin, pregabalin, tricyclic antidepressants, mixed serotonin-norepinephrine reuptake inhibitors, tramadol and opioids. The field of neuropathic pain research and treatment is in the early stages of development, with many unmet goals. In coming years, several advances are expected in the basic and clinical sciences of neuropathic pain, which will provide new and improved therapies for patients who continue to experience this disabling condition.

Abstract
Purpose: Postoperative pain is the commonest reason for delayed discharge and unanticipated hospital admission after ambulatory surgery. We investigated the severity of pain at 24 hr postoperatively and determined the most painful procedures. The need for further medical advice and clarity of postoperative analgesia instructions were also studied.

Methods: Five thousand seven hundred and three ambulatory surgical patients were telephoned 24 hr postoperatively. Patients graded their pain using the ten-point self-assessing verbal scale (0 = no pain, 10 = worst pain). Data were analyzed in two groups, those with moderate to severe pain (pain score 4-10) and those with no or mild pain (0-3).

Results: Thirty percent of patients (1,495/5,703) had moderate to severe pain. Microdiscectomy, laparoscopic cholecystectomy, shoulder surgery, elbow/hand surgery, ankle surgery, inguinal hernia repair, and knee surgery were identified as the procedures causing most pain at 24 hr. 13.2% of patients needed medical advice by telephone, 1.4% made an unplanned visit to a doctor while the rate of readmission to the hospital was 0.08%. Ninety-eight percent found postoperative instruction sheets and advice helpful. Eighty-eight percent of patients indicated that analgesic instructions were absolutely clear.

Conclusion: This study has identified the more painful common ambulatory surgical procedures which will allow take home analgesia to be tailored according to individual procedures. Further improvement in analgesic instructions may help in better pain management of ambulatory surgery patients.

This document is about how to talk to hospital staff about how pain is affecting you, so that they can help keep you as comfortable as possible.

Abstract
Objective: To quantify the effects of varying opioid prescribing patterns after surgery on dependence, overdose, or abuse in an opioid naive population.

Design: Retrospective cohort study.

Setting: Surgical claims from a linked medical and pharmacy administrative database of 37 651 619 commercially insured patients between 2008 and 2016.

Participants: 1 015 116 opioid naive patients undergoing surgery.

Main outcome measures: Use of oral opioids after discharge as defined by refills and total dosage and duration of use. The primary outcome was a composite of misuse identified by a diagnostic code for opioid dependence, abuse, or overdose.

Results: 568 612 (56.0%) patients received postoperative opioids, and a code for abuse was identified for 5906 patients (0.6%, 183 per 100 000 person years). Total duration of opioid use was the strongest predictor of misuse, with each refill and additional week of opioid use associated with an adjusted increase in the rate of misuse of 44.0% (95% confidence interval 40.8% to 47.2%, P<0.001), and 19.9% increase in hazard (18.5% to 21.4%, P<0.001), respectively.

Conclusions: Each refill and week of opioid prescription is associated with a large increase in opioid misuse among opioid naive patients. The data from this study suggest that duration of the prescription rather than dosage is more strongly associated with ultimate misuse in the early postsurgical period. The analysis quantifies the association of prescribing choices on opioid misuse and identifies levers for possible impact.

Abstract
Objectives: Despite the growing number of ambulatory operations knowledge of predictive factors of postoperative pain after ambulatory surgery is limited. Therefore, the aim of this study was to identify predictive factors of postoperative pain after ambulatory surgery.

Methods: In this cross-sectional study, 648 patients were included. A wide variety of elective ambulatory operations were performed. Pain assessments were made before the operation and during a 4-day period postoperatively, using a 100 mm visual analog scale. Patient characteristics, type of surgery, and type of anesthesia were recorded. In addition, preoperative expectations of postoperative pain by physician and patient were assessed. Finally, several scores about psychologic parameters were measured: pain catastrophizing, surgical anxiety, and optimism. Stepwise logistic regression analysis was performed to identify factors that independently predict the risk of having postoperative pain (defined by a visual analog scale >40 mm) on days 0 to 4.

Results: The most important predictor of postoperative pain was the presence of preoperative pain. Other predictors were anticipated postoperative pain by the clinician, preoperative high expectations of postoperative pain by the patient, younger age, and fear of short-term consequences of the operation. Regional anesthetic technique compared with general anesthesia decreased the risk of acute postoperative pain only on the day of the operation.

Discussion: Several predictive factors of postoperative pain after ambulatory surgery were identified in this study. These factors should be taken into account when planning postoperative analgesia for ambulatory surgery.

Abstract
Aims: The aims of the current study were to determine the prevalence and incidence of prescription opioid analgesic use in Australia and compare the characteristics of people with and without cancer initiating prescription opioid analgesics.

Methods: A retrospective population-based study was conducted using the random 10% sample of adults who were dispensed prescription opioid analgesics in Australia between July 2013 and June 2017 through the Pharmaceutical Benefits Scheme. Poisson regression was used to calculate rate ratios (RR) for opioid prevalence and incidence. The characteristics of people initiating opioids, including type of opioid initiated, total oral morphine equivalents dispensed, prescriber speciality, medical comorbidities, and past analgesic and benzodiazepine use, were compared for people with and without cancer.

Results: Opioid prevalence increased {RR = 1.006 [95% confidence interval (CI) 1.004, 1.008]}, while incidence decreased [RR = 0.977 (95% CI 0.975,0.979)] from 2013/2014 to 2016/2017. There were between 287 677 and 307 772 prevalent users each year. In total, 769 334 adults initiated opioids between 2013/2014 and 2016/2017, and half of these initiations were by general practitioners. Initiation with a strong opioid occurred in 55.8% of those with cancer and 28.2% of those without cancer.

Conclusion: Rates of opioid use have remained high since 2013, with approximately 3 million adults using opioids and over 1.9 million adults initiating opioids each year. Between 2013 and 2017, opioid prevalence has slightly increased but incidence has decreased. People without cancer account for the majority of opioid use and are more likely to be initiated on short-acting and weak opioids. Initiation of strong opioids has increased over time, reinforcing concerns about increased use and the harms associated with strong opioids in the community.

Abstract
Objective: Misuse of prescription opioids is a significant public health issue in Australia. There has been a rapid rise in prescription opioid use, with an associated increase in overdose and death. The over-prescribing of oral opioids, especially oxycodone, in the ED has been identified as a contributor to this problem overseas. It is unclear if similar practice occurs in the Australian ED. The primary aim of our study was to identify the incidence of oral oxycodone administration to patients within the ED. The secondary outcome was to identify the incidence of oxycodone prescribed to patients on discharge from the ED into the community.

Methods: Our study was designed as an observational, retrospective data analysis of the incidence of oxycodone prescribed within the three EDs of a large Australian public health service. All immediate-release (IR) and slow-release (SR) oral oxycodone prescribed over a 4-year period (2015-2018) was included.

Results: There were 890 557 presentations to the three EDs during the period, which resulted in 288 242 episodes of oxycodone administration within department, equivalent to 324 administrations per 1000 presentations. There were 39 381 prescriptions for oxycodone provided on discharge, resulting in an incidence of 44 prescriptions per 1000 discharged. The most frequently prescribed opioid medication in the ED was oxycodone IR 5 mg, 78.6% of discharge prescriptions generated provided a maximum quantity (20 for IR formulation or 28 for SR) of tablets allowable under the pharmaceutical benefits scheme.

Conclusions: There is a higher incidence of oxycodone prescribing in the Australian ED than previously recognised. An overuse of oxycodone may be contributing to adverse patient outcomes and a public health crisis. Hospitals should consider appropriate steps to reduce the incidence of opioid prescribing and the supply of these medications into the community.

Abstract
Objectives: Surgical fear is one of the most important psychological risk factors for postoperative pain, but less is known about the contribution of protective factors. This study investigated somatic and psychological risk and resilience factors of postoperative pain and validated the German version of the Surgical Fear Questionnaire (SFQ).

Setting: University Hospital of Marburg, Germany.

Design: Single-centre observational study and cross-sectional validation study.

Participants: Data for validating the SFQ were obtained from a cross-sectional observational study (N=198, mean age 43.6 years, 58.8% female) with persons undergoing different kinds of elective surgery. A sample of N=196 (mean age 43.0 years, 45.4% female) undergoing elective (orthopaedic) surgery was analysed to investigate somatic and psychological predictors of relevant acute postsurgical pain (APSP).

Outcome measures: Participants completed preoperative and postoperative assessments at postoperative days 1, 2 and 7. Presurgical pain, age, gender, pain expectation, surgical setting, physical status, anaesthesia, surgical fear, pain catastrophising, depression, optimism and self-efficacy were examined as predictors.

Results: Confirmatory factor analysis confirmed the original two-factor structure of the SFQ. Correlation analyses indicated good convergent and divergent validity. Internal consistency (Cronbach's α) was between 0.85 and 0.89. Blockwise logistic regression analyses for the risk of APSP revealed outpatient setting, higher preoperative pain, younger age, more surgical fear and low dispositional optimism as significant predictors.

Conclusions: The German SFQ is a valid, reliable and economical instrument with which the important psychological predictor surgical fear can be assessed. Modifiable factors that increase the risk of postoperative pain were higher pain intensity before surgery and being fearful about negative consequences of the surgery whereas positive expectations seem to buffer against postsurgical pain.

Abstract
Objective: To determine time to opioid cessation post discharge from hospital in persons who had been admitted to hospital for a surgical procedure and were previously naïve to opioids.

Design, setting and participants: Retrospective cohort study using administrative health claims database from the Australian Government Department of Veterans' Affairs (DVA). DVA gold card holders aged between 18 and 100 years who were admitted to hospital for a surgical admission between 1 January 2014 and 30 December 2015 and naïve to opioid therapy prior to admission were included in the study. Gold card holders are eligible for all health services that DVA funds.

Main outcome measures: The outcome of interest was time to cessation of opioids, with follow-up occurring over 12 months. Cessation was defined as a period without an opioid prescription that was equivalent to three times the estimated supply duration. The proportion who became chronic opioid users was defined as those who continued taking opioids for greater than 90 days post discharge. Cumulative incidence function with death as a competing event was used to determine time to cessation of opioids post discharge.

Results: In 2014-2015, 24 854 persons were admitted for a surgical admission. In total 3907 (15.7%) were discharged on opioids. In total 3.9% of those discharged on opioids became chronic users of opioids. The opioid that the patients were most frequently discharged with was oxycodone; oxycodone alone accounted for 43%, while oxycodone with naloxone accounted for 8%.

Conclusions: Opioid initiation post-surgical hospital admission leads to chronic use of opioids in a small percentage of the population. However, given the frequency at which surgical procedures occur, this means that a large number of people in the population may be affected. Post-discharge assessment and follow-up of at-risk patients is important, particularly where psychosocial elements such as anxiety and catastrophising are identified.

Abstract
Involving pharmacists in the process of comparing the medications that should be ordered for a patient with the new medications that are currently ordered and resolving differences improves accuracy, decreases mortality, and improves transitions of care.

Abstract
Objective: EDs are a common source of prescription opioids on discharge. We explored opioid prescribing practices in an ED at a tertiary hospital in Victoria, Australia.

Methods: A retrospective audit over a 6 month period of patients discharged from the ED to the community with the maximum allowable quantities of prescription opioids.

Results: There was a total of 3301 patient-episodes discharged with a prescription from the ED. Of these, 766 (23.2%, 95% confidence interval [CI] 21.8-24.6) were prescribed opioids, with over half discharged with the maximum allowable quantities of prescription opioids. Immediate-release opioids were prescribed in 362 (85.8%, 95% CI 82.5-89.1) patient-episodes, a combination of immediate-release and slow-release preparations were prescribed in 29 (6.9%, 95% CI 4.5-9.3) and 31 (7.3%, 95% CI 4.8-9.8) were prescribed as slow-release opioids alone. Co-prescription of other analgesia with opioids occurred in 152 (36.0%, 95% CI 31.4-40.6) patient-episodes. Possible drug interactions between opioids and other medications were noted in 117 (27.7%, 95% CI 23.4-32.0) patient-episodes. Discharge summaries were prepared for 360 (85.3%, 95% CI 81.9-88.7) patient-episodes, but only 171 (40.5%, 95% CI 35.8-45.2) included a plan to address the opioids, be that an opioid-weaning regimen, analgesia review or referral to a pain specialist on discharge.

Conclusion: Opioid prescribing was common in this ED, with almost one-quarter of discharge prescriptions being for a prescription opioid. This audit highlights potential areas for practice improvement including review of the quantity of opioid tablets prescribed as well as an opioid plan on discharge from the ED.

Abstract
Post-surgical opioid prescribing intended for the short-term management of acute pain may lead to long-term opioid use. This study was undertaken to determine the prevalence of persistent post-surgical opioid use and patient-related factors associated with post-surgical opioid use. One thousand and thirteen opioid-naïve patients awaiting elective surgery in a tertiary private hospital in Sydney were enrolled. Preoperatively, patients completed a questionnaire comprising potential predictors of persistent post-surgical opioid use. Patients underwent surgery with routine perioperative care, and were followed up at 90 to 120 days after surgery to determine opioid use. Factors associated with opioid use were assessed with logistic regression. We had an overall response rate of 95.8% (n=970) of patients, of whom 10.5% (n=102) continued to use opioids at >90 days after surgery. On surgical subtype analysis, the prevalence of persistent opioid use was 23.6% after spinal surgery, and 13.7% after orthopaedic surgery. Four factors were independently associated with persistent post-surgical opioid use in a multivariate model: having orthopaedic (odds ratio [OR] 4.6, 95% confidence interval [CI] 2.0 to 10.8, P <0.001) or spinal surgery (OR 4.0, 95% CI 1.7 to 9.2, P <0.001), anxiety (OR 2.1, 95% CI 1.1 to 4.1, P=0.03), attending pre-admission clinic (OR 3.7, 95% CI 1.6 to 8.6, P=0.002), and higher self-reported pain score at >90 days after surgery (P <0.001). More than 10% of opioid-naïve patients undergoing elective surgery experience persistent post-surgical opioid use. Identification of factors associated with persistent post-surgical opioid use may allow development of a risk stratification tool to predict those at highest risk.