An international multidisciplinary consensus statement on the prevention of opioid-related harm in adult surgical patients.

This international multidisciplinary consensus statement was developed to provide balanced guidance on the safe peri-operative use of opioids in adults. An international panel of healthcare professionals evaluated the literature relating to postoperative opioid-related harm, including persistent postoperative opioid use; opioid-induced ventilatory impairment; non-medical opioid use; opioid diversion and dependence; and driving under the influence of prescription opioids. Recommended strategies to reduce harm include pre-operative assessment of the risk of persistent postoperative opioid use; use of an assessment of patient function rather than unidimensional pain scores alone to guide adequacy of analgesia; avoidance of long-acting (modified-release and transdermal patches) opioid formulations and combination analgesics; limiting the number of tablets prescribed at discharge; providing deprescribing advice; avoidance of automatic prescription refills; safe disposal of unused medicines; reducing the risk of opioid diversion; and better education of healthcare professionals, patients and carers. This consensus statement provides a framework for better prescribing practices that could help reduce the risk of postoperative opioid-related harm in adults.

An observational study of perioperative risk associated with aortic stenosis in non-cardiac surgery.

This prospective multicentre observational study investigated the risk of non-cardiac surgery in patients with moderate or severe aortic stenosis (AS). Patients with AS undergoing non-cardiac surgery in five New Zealand hospitals between August 2011 and September 2015 were studied. Preoperative variables were analysed for a significant association with postoperative major adverse cardiac events (MACE) and 30-day mortality. Of the 147 patients recruited, 13 (9%) died within 30 days and 33 (22%) had a MACE. Using univariate analysis, patients with severe AS had four times higher 30-day mortality than patients with moderate AS (16% versus 4%, P=0.007). Other factors associated with increased 30-day mortality included having a smaller aortic valve area, smaller dimensionless severity index, concomitant mitral regurgitation, and higher overall surgical risk. Patients with symptoms attributable to AS had a higher incidence of MACE compared to patients without symptoms (36% versus 16%, P=0.011). Variables significantly associated with both 30-day mortality and MACE were age, American Society of Anesthesiologists physical status, emergency surgery, New York Heart Association classification, preoperative albumin level, frailty, and history of congestive heart failure. Using multivariate analysis, emergency surgery, symptoms attributable to AS, preoperative albumin level, and AVA remained significantly associated with adverse outcome. While these findings should be interpreted with caution due to the observational nature of the study, limited power and multiple simultaneous comparisons, they suggest that patients with severe AS have a higher risk of adverse outcome after non-cardiac surgery than patients with moderate AS.

A retrospective observational study of patients with dilated cardiomyopathy undergoing non-cardiac surgery.

The perioperative risks and factors associated with adverse cardiac outcomes in patients with dilated cardiomyopathy undergoing non-cardiac surgery are unknown. Interrogation of the Nelson Hospital transthoracic echocardiogram database identified 127 patients with dilated cardiomyopathy who satisfied the study criteria and underwent non-cardiac surgery between June 1999 and July 2013. Demographic and clinical data along with postoperative death within 30 days or a major adverse cardiac event were retrieved and analysed. The mean age was 75.9 years. Seventy-one percent of the patients had severe impairment of left ventricular function and 35% had a severely dilated left ventricle. A major adverse cardiac event occurred in 18.1% of patients and 5.5% of patients died within 30 days of surgery. Increased surgical risk and absence of cerebrovascular disease were associated with adverse outcome (P <0.001, P <0.05, respectively). Forty-three and a half percent (43.5%) of patients undergoing high-risk surgery had an adverse outcome compared to 36.1% and 5.9% for moderate and low-risk surgery, respectively. A major adverse cardiac event was observed in 26.7% of patients with cardiovascular disease compared to 9.8% of patients without cardiovascular disease. We were unable to exclude an influence of other potential risk factors due to the retrospective observational nature of the study. These findings highlight a potential increase in complications with moderate or high surgical risk, whilst are reassuring in demonstrating the relative safety of low-risk surgery in this group of high-risk patients.

A randomized controlled trial of postoperative analgesia following total knee replacement: transdermal Fentanyl patches versus patient controlled analgesia (PCA).

BACKGROUND: This randomized controlled trial compared a standard patient controlled analgesic (PCA) regime with a transdermal and oral Fentanyl regime for post-operative pain management in patients undergoing total knee replacement. METHODS: One hundred and ninety-six patients undergoing total knee replacement were recruited. Pre- and post-operatively Visual Analogue Score (VAS), Oxford Knee Score, Health Anxiety and Depression Score and Brief Pain Inventory Score were completed. According to the day 1, VAS score patients were randomly allocated to either a PCA regime or a Fentanyl transdermal/oral regime. Patient reported outcomes were measured until the patients were discharged. RESULTS: The results demonstrate that in terms of analgesic effect, day of discharge and side effect profile the two regimes are comparable. CONCLUSIONS: We conclude that a Fentanyl transdermal regime provides adequate analgesic effect comparable to a standard PCA regime in conjunction with a low side effect profile. Using a transdermal analgesic system provides efficient continuous delivery enabling a smooth transition from hospital to home within the first week. Transdermal Fentanyl provides an alternative analgesic regime that can provide an equivalent analgesic effect so as to enable a satisfactory outcome for the patient in terms of function and pain. LEVEL OF EVIDENCE: II.

Costs and consequences: a review of discharge opioid prescribing for ongoing management of acute pain.

Over recent years there has been a growing need for patients to be sent home from hospital with prescribed opioids for ongoing management of their acute pain. Increasingly complex surgery is being performed on a day-stay or 23-hour-stay basis and inpatients after major surgery and trauma are now discharged at a much earlier stage than in the past. However, prescription of opioids to be self-administered at home is not without risk. In addition to the potential for acute adverse effects, including opioid-induced ventilatory impairment and impairment of driving skills, a review of the literature shows that opioid use continues in some patients for some years after surgery. There are also indications that over-prescription of discharge opioids occur with a significant amount not consumed, resulting in a potentially large pool of unused opioid available for later use by either the patient or others in the community. Concerns about the potential for harm arising from prescription of opioids for ongoing acute pain management after discharge are relatively recent. However, at a time when serious problems resulting from the non-medical use of opioids have reached epidemic proportions in the community, all doctors must be aware of the potential risks and be able to identify and appropriately manage patients where there might be a risk of prolonged opioid use or misuse. Anaesthetists are ideally placed to exercise stewardship over the use of opioids, so that these drugs can maintain their rightful place in the post-discharge analgesic pharmacopoeia.

Home blood pressure monitoring in an anaesthetic pre-admission clinic.

We suspected that many high blood pressure measurements taken in our anaesthetic pre-assessment clinic and immediately prior to induction of anaesthesia were unusually elevated due to a 'white coat' effect. These high blood pressure measurements were causing late cancellations of surgery, even though white coat measurements may not be representative of the patient's usual blood pressure or of their risk of end-organ damage due to hypertension. In this audit, patients with high blood pressure in our pre-admission clinic were provided with training and a home blood pressure monitor to use prior to surgery. These were compared to the pre-admission clinic measurements to determine the incidence of white coat hypertension. We also compared home to general practice blood pressure monitoring where possible. Fifty-two patients were provided with monitors. Fifty-one of these took at least five measurements at home. Thirty-four (66%) patients had average measurements at home at least 20 mmHg lower than pre-admission clinic measurements. A total of 33% of general practice clinic measurements were also ≥ 20 mmHg higher than average home measurements. White coat hypertension was common in our audit population. Relying on average home blood pressure measurements rather than 'one off' in-hospital measurements may have helped to prevent the postponement or cancellation of surgery for 13 patients who had recorded blood pressure ≥ 180/110 mmHg in our pre-admission clinic.

Pain relief and opioid requirements in the first 24 hours after surgery in patients taking buprenorphine and methadone opioid substitution therapy.

The number of patients in buprenorphine opioid substitution therapy (BOST) or methadone opioid substitution therapy (MOST) programs is increasing. If these patients require surgery, it is generally agreed that methadone should be continued perioperatively. While some also recommend that buprenorphine is continued, concerns that it may limit the analgesic effectiveness of full mu-opioid agonists have led others to suggest that it should cease before surgery. However, no good evidence exists for either course of action. Therefore, we undertook a retrospective cohort study comparing pain relief and opioid requirements in the first 24 hours after surgery in 22 BOST and 29 MOST patients prescribed patient-controlled analgesia. There were no significant differences in pain scores (rest and movement), incidence of nausea or vomiting requiring treatment, or sedation between the BOST and MOST patient groups overall, or between those patients within each of these groups who had and had not received their methadone or buprenorphine the day after surgery. There were also no significant differences in patient-controlled analgesia requirements between BOST and MOST patient groups overall, or between patients who did or did not receive MOST on the day after surgery. BOST patients who were not given their usual buprenorphine the day after surgery used significantly more patient-controlled analgesia opioid (P=0.02) compared with those who had received their dose. These results confirm that continuation of buprenorphine perioperatively is appropriate.

Pharmacokinetics of oxycodone after subcutaneous administration in a critically ill population compared with a healthy cohort.

This study aimed to characterise and compare the absorption pharmacokinetics of a single subcutaneous dose of oxycodone in critically ill patients and healthy subjects. Blood samples taken at intervals from two minutes to eight hours after a subcutaneous dose of oxycodone in patients (5 mg) and healthy volunteers (10 mg) were assayed using high performance liquid chromatography. Data were analysed using a non-compartmental approach and presented as mean (SD). Parameters were corrected for dose differences between the groups assuming linear kinetics. Ten patients (eight male, two female) and seven healthy male subjects were included. Maximum venous concentration and area under the concentration curve were approximately two-fold lower in the patient group for an equivalent dose, suggesting either reduced bioavailability or increased clearance: maximum venous concentration 0.14 ± 0.06 vs 0.05 ± 0.02 µg/ml (P <0.0001); area under the concentration curve 19.50 ± 9.15 vs 9.72 ± 2.71 µg/ml/minute (P <0.001) respectively. However, time to maximum venous concentration and mean residence time were not different, suggesting similar absorption rates: time to maximum venous concentration 22.10 ± 18.0 vs 20.50 ± 16.10 minutes (P=0.81); mean residence time 353 ± 191 vs 291 ± 80 minutes (P=0.26). Kinetic parameters were less variable in patients than in volunteers. The patients therefore had reduced exposure to subcutaneous oxycodone. This warrants further model-based analysis and experimentation. Dose regimens for subcutaneous oxycodone developed in healthy volunteers cannot be directly translated to critically ill patients.

Pre-exercise screening and health coaching in CHD secondary prevention: a qualitative study of the patient experience.

Secondary prevention programmes can be effective in reducing morbidity and mortality from coronary heart disease (CHD). In particular, UK guidelines, including those from the Department of Health, emphasize physical activity. However, the effects of secondary prevention programmes with an exercise component are moderate and uptake is highly variable. In order to explore patients' experiences of a pre-exercise screening and health coaching programme (involving one-to-one consultations to support exercise behaviour change), semi-structured telephone interviews were undertaken with 84 CHD patients recruited from primary care. The interviews focused on patients' experiences of the intervention including referral and any recommendations for improvement. A thematic analysis of transcribed interviews showed that the majority of patients were positive about referral. However, patients also identified a number of barriers to attending and completing the programme, including a belief they were sufficiently active already, the existence of other health problems, feeling unsupported in community-based exercise classes and competing demands. Our findings highlight important issues around the choice of an appropriate point of intervention for programmes of this kind as well as the importance of appropriate patient selection, suggesting that the effectiveness of health coaching may be under-reported as a result of including patients who are not yet ready to change their behaviours.

Walk or run? Is high-intensity exercise more effective than moderate-intensity exercise at reducing cardiovascular risk?

The benefits of exercise in the prevention of cardiovascular disease are irrefutable. However, the optimum 'dose' of exercise in order to derive the maximum cardiovascular benefit is not certain. Current national and international guidelines advocate the benefits of moderate-intensity exercise. The relative benefits of vigorous versus moderate-intensity exercise have been studied in large epidemiological studies, addressing coronary heart disease and mortality, as well as smaller randomized clinical trials which assessed effects on cardiovascular risk factors. There is evidence that exercise intensity, rather than duration or frequency, is the most important variable in determining cardioprotection. Applying this evidence into practice must take into account the impact of baseline fitness, compliance and the independent risk associated with a sedentary lifestyle. This review aims to evaluate the role of exercise intensity in the reduction of cardiovascular risk, and answer the question: should you be advising your patients to walk or run?

Acute pain management in opioid-tolerant patients: a growing challenge.

In Australia and New Zealand, in parallel with other developed countries, the number of patients prescribed opioids on a long-term basis has grown rapidly over the last decade. The burden of chronic pain is more widely recognised and there has been an increase in the use of opioids for both cancer and non-cancer indications. While the prevalence of illicit opioid use has remained relatively stable, the diversion and abuse of prescription opioids has escalated, as has the number of individuals receiving methadone or buprenorphine pharmacotherapy for opioid addiction. As a result, the proportion of opioid-tolerant patients requiring acute pain management has increased, often presenting clinicians with greater challenges than those faced when treating the opioid-naïve. Treatment aims include effective relief of acute pain, prevention of drug withdrawal, assistance with any related social, psychiatric and behavioural issues, and ensuring continuity of long-term care. Pharmacological approaches incorporate the continuation of usual medications (or equivalent), short-term use of sometimes much higher than average doses of additional opioid, and prescription of non-opioid and adjuvant drugs, aiming to improve pain relief and attenuate opioid tolerance and/or opioid-induced hyperalgesia. Discharge planning should commence at an early stage and may involve the use of a 'Reverse Pain Ladder' aiming to limit duration of additional opioid use. Legislative requirements may restrict which drugs can be prescribed at the time of hospital discharge. At all stages, there should be appropriate and regular consultation and liaison with the patient, other treating teams and specialist services.

Opioids, ventilation and acute pain management.

Despite the increasing use of a variety of different analgesic strategies, opioids continue as the mainstay for management of moderate to severe acute pain. However concerns remain about their potential adverse effects on ventilation. The most commonly used term, respiratory depression, only describes part of that risk. Opioid-induced ventilatory impairment (OIVI) is a more complete term encompassing opioid-induced central respiratory depression (decreased respiratory drive), decreased level of consciousness (sedation) and upper airway obstruction, all of which, alone or in combination, may result in decreased alveolar ventilation and increased arterial carbon dioxide levels. Concerns about OIVI are warranted, as deaths related to opioid administration in the acute pain setting continue to be reported. Risks are often said to be higher in patients with obstructive sleep apnoea. However, the tendency to use the term 'obstructive sleep apnoea' to encompass the much broader spectrum of sleep- and obesity-related hypoventilation syndromes and the related misuse of terminology in papers relating to obstructive sleep apnoea and sleep-disordered breathing remain significant problems in discussions of opioid-related effects. Opioids given for management of acute pain must be titrated to effect for each patient. However strategies aiming for better pain scores alone, without highlighting the need for appropriate monitoring of OIVI, can and will lead to an increase in adverse events. Therefore, all patients must be monitored appropriately for OIVI (at the very least using sedation scores as a '6th vital sign') so that it can be detected at an early stage and appropriate interventions triggered.

Secondhand smoke exposure and survival following acute coronary syndrome: prospective cohort study of 1261 consecutive admissions among never-smokers.

OBJECTIVE: To determine whether exposure to secondhand smoke is associated with early prognosis following acute coronary syndrome. DESIGN, SETTING AND PARTICIPANTS: We interviewed consecutive patients admitted to nine Scottish hospitals over 23 months. Information was obtained, via questionnaire, on age, sex, smoking status, postcode of residence and admission serum cotinine concentration was measured. Follow-up data were obtained from routine hospital admission and death databases. RESULTS: Of the 5815 participants, 1261 were never-smokers. Within 30 days, 50 (4%) had died and 35 (3%) had a non-fatal myocardial infarction. All-cause deaths increased from 10 (2.1%) in those with cotinine < or =0.1 ng/ml to 22 (7.5%) in those with cotinine >0.9 ng/ml (chi(2) test for trend p<0.001). This persisted after adjustment for potential confounders (cotinine >0.9 ng/ml: adjusted OR 4.80, 95% CI 1.95 to 11.83, p = 0.003). The same dose response was observed for cardiovascular deaths and death or myocardial infarction. CONCLUSIONS: Secondhand smoke exposure is associated with worse early prognosis following acute coronary syndrome. Non-smokers need to be protected from the harmful effects of secondhand smoke.

Driving behavior under the influence of cannabis or cocaine.

OBJECTIVE: The purpose of this study is first to describe perceptions of driving under the influence of cannabis or cocaine among clients in treatment and, second, to assess whether these perceptions are related to the frequency of driving under the influence of cannabis or cocaine. METHODS: A questionnaire was administered to clients in treatment for abuse of either cocaine or cannabis, many of whom also had a problem with alcohol; additional groups of clients consisted of those in smoking cessation and gambling programs (N = 1021). Open-ended and close-ended questions were used to assess self-reported effects of cannabis or cocaine on driving and frequency of driving under the influence of cannabis, cocaine, or alcohol. RESULTS: Two dimensions of driving behavior under the influence of cocaine or cannabis were found in both qualitative and quantitative analyses: 1) physical effects and 2) reckless styles of driving. Common physical effects for both drugs were heightened nervousness, greater alertness, and poorer concentration. In terms of driving behavior, cautious or normal driving was commonly reported for cannabis, whereas reckless or reduced driving ability was frequently reported for cocaine. When comparing negative physical effects and reckless style of driving with frequency of driving under the influence of cannabis or cocaine, increased negative physical effects from cannabis were inversely related to frequency of driving under the influence of cannabis (p = .001), but other relationships were not significant. CONCLUSIONS: The findings indicate that both cannabis and cocaine have detrimental but different effects on driving. The negative physical effects of cannabis may reduce the likelihood of driving under the influence of cannabis.

Oral transmucosal fentanyl citrate versus placebo for painful dressing changes: a crossover trial.

OBJECTIVE: Fentanyl is a potent opioid that is well absorbed via the oral mucosa. It can be given as an oral lozenge. The onset of analgesia is rapid and matches the pain profile observed at dressing changes. METHOD: Patients experiencing pain during daily dressing changes were given entonox plus either placebo or oral transmucosal fentanyl citrate (OTFC) for two consecutive dressing changes in a randomised double-blind placebo-controlled crossover trial. RESULTS: Nine patients were recruited. The mean worst pain score during dressing changes was 7/10 with placebo and 4/10 with OTFC; the reduction in pain achieved with OTFC was significant. The mean number of breaths of entonox taken during the dressing change was 27.67 with placebo and 4.67 with OTFC; the reduction in the number of entonox breaths with OTFC was significant. One patient in the OTFC group suffered nausea. CONCLUSION: Compared with placebo, OTFC improved analgesia during painful dressing changes without an increase in side-effects.

An audit of intrathecal morphine analgesia for non-obstetric postsurgical patients in an adult tertiary hospital.

We conducted a retrospective audit of adult non-obstetric patients who had received a single dose of intrathecal morphine for postoperative analgesia. These patients were predominantly admitted to a regular postsurgical ward with strict hourly nursing observations, treatment protocols in place and supervision by an Acute Pain Service for the first 24 hours after intrathecal morphine administration. A total of 409 cases were examined for sedation score, incidence of respiratory depression and other side-effects, admission to the high dependency or intensive care unit and opioid-tolerance. Respiratory depression was defined as requiring treatment with naloxone (implying a sedation score of 3 irrespective of respiratory rate), or a sedation score of 2 with a respiratory rate less than six breaths per minute. The patients were predominantly elderly (57.2% were over the age of 70 years) and 84.8% had undergone vascular surgery. Of the total of 409 cases, only one case of respiratory depression was observed. A total of 77 patients were admitted to high dependency or intensive care unit for various reasons including management of postsurgical complications and patient co-morbidities. Our findings suggest that elderly patients who receive intrathecal morphine analgesia can be safely managed in a regular postsurgical ward.

Delivery of local anaesthetic via a sternal catheter to reduce the pain caused by sternal fractures: first case series using the new technique.

Sternal fractures cause considerable pain, and a proportion of patients require admission for analgesia. Local anaesthetic techniques have been used to reduce the pain from chest wall injuries and may reduce complications from these injuries. The use of a local anaesthetic delivered via a sternal catheter over a fractured sternum has been described in a patient whose pain was inadequately controlled with opiates. This technique was recently offered to patients in the emergency department at the Royal Devon and Exeter Hospital, Exeter, UK, and the experiences of patients and doctors are reported. Findings from this first case series suggest that the technique seems to be effective, well tolerated and acceptable to patients.