Developing a risk stratification tool for predicting opioid-related respiratory depression after non-cardiac surgery: a retrospective study

OBJECTIVES

Accurately assessing the probability of significant respiratory depression following opioid administration can potentially enhance perioperative risk assessment and pain management. We developed and validated a risk prediction tool to estimate the probability of significant respiratory depression (indexed by naloxone administration) in patients undergoing noncardiac surgery.

DESIGN

Retrospective cohort study.

SETTING

Single academic centre.

PARTICIPANTS

We studied n=63 084 patients (mean age 47.1±18.2 years; 50% men) who underwent emergency or elective non-cardiac surgery between 1 January 2007 and 30 October 2017.

INTERVENTIONS

A derivation subsample reflecting two-thirds of available patients (n=42 082) was randomly selected for model development, and associations were identified between predictor variables and naloxone administration occurring within 5 days following surgery. The resulting probability model for predicting naloxone administration was then cross-validated in a separate validation cohort reflecting the remaining one-third of patients (n=21 002).

RESULTS

The rate of naloxone administration was identical in the derivation (n=2720 (6.5%)) and validation (n=1360 (6.5%)) cohorts. The risk prediction model identified female sex (OR: 3.01; 95% CI: 2.73 to 3.32), high-risk surgical procedures (OR: 4.16; 95% CI: 3.78 to 4.58), history of drug abuse (OR: 1.81; 95% CI: 1.52 to 2.16) and any opioids being administered on a scheduled rather than as-needed basis (OR: 8.31; 95% CI: 7.26 to 9.51) as risk factors for naloxone administration. Advanced age (OR: 0.971; 95% CI: 0.968 to 0.973), opioids administered via patient-controlled analgesia pump (OR: 0.55; 95% CI: 0.49 to 0.62) and any scheduled non-opioids (OR: 0.63; 95% CI: 0.58 to 0.69) were associated with decreased risk of naloxone administration. An overall risk prediction model incorporating the common clinically available variables above displayed excellent discriminative ability in both the derivation and validation cohorts (c-index=0.820 and 0.814, respectively).

CONCLUSION

Our cross-validated clinical predictive model accurately estimates the risk of serious opioid-related respiratory depression requiring naloxone administration in postoperative patients.

Risk factors for opioid toxicity requiring naloxone rescue in adults: a case-control study

BACKGROUND

Opioid-induced sedation and respiratory depression (OSRD) is a potentially life-threatening side effect of opioid analgesia. However, little is known about the individual and clinical-related factors associated with OSRD in the New Zealand context.

AIM

To identify risk factors for OSRD in patients admitted to a large regional health board in New Zealand-Auckland District Health Board (ADHB).

METHOD

A retrospective matched case-control study design was undertaken among adults who were admitted to ADHB and prescribed opioids in hospital between August 2015 and April 2020. Those who were prescribed opioids and received naloxone for OSRD were defined as cases, whereas those who received opioids but did not experience OSRD were identified as controls. Cases and controls were matched on a 1:1 basis by age (± 10 years). Data were retrieved from the electronic medical records of ADHB. A conditional logistic regression model was used to identify the risk factors for OSRD.

RESULTS

We identified 51 cases, and these were matched with 51 control patients. The odds of experiencing OSRD were four times higher among opioid-naïve patients compared to those exposed to opioids prior to hospital admission (OR  4.113; 95% CI 1.14-14.89). Increased risk of OSRD was also associated with higher serum creatinine level prior to OSRD episode (OR 1.015; 95% CI 1.01-1.03) and a higher oral morphine milligram equivalent (OME) (OR 1.023; 95% CI 1.01-1.04).

CONCLUSION

Increased risk of OSRD was associated with a higher OME, a higher serum creatinine level prior to OSRD episode, and opioid naivety. Our findings can inform policies that aim to prevent serious adverse effects related to opioids.

Predictors of Serious Opioid-Related Adverse Drug Events in Hospitalized Patients

OBJECTIVE

Opioids are high-risk medications in the inpatient setting because of their potential for significant patient harm. The primary objective was to identify risk factors that predispose inpatients to develop opioid-related adverse drug events (ORADE) requiring the use of naloxone.

METHODS

In a retrospective case-control study, patients were included according to the following criteria: 18 years or older, 1 administered opioid doses or more, and admitted for 24 hours or more. Patients were excluded if they had a prehospital drug overdose, other indications for naloxone use, or were admitted to an intensive care unit, psychiatric medical unit, or in the emergency department. Patients were classified as cases if naloxone was administered and a selection of controls were frequency matched 2:1 based on medical or surgical status. A logistic regression model was used to evaluate for risk factors for ORADE.

RESULTS

A total of 275 cases and 592 control patients were included into the final analysis. Variables that were associated with greater odds of naloxone administration included age of 65 years or older, female, length of stay, pulmonary diagnoses, use of gabapentinoids, and patient-controlled analgesia use. Antihistamines, continuous infusion, and intermittent nurse administered intravenous bolus routes had a negative association with naloxone use.

CONCLUSIONS

Several risk factors were found to be associated with ORADE supporting many of the previously described risk factors, and the discovery of potential new ones, such as gabapentinoid use. Health care providers should consider the risk factors for hospitalized patients receiving opioids who may warrant lower doses, additional monitoring, or alternative agents.

Predicting opioid-induced oversedation in hospitalised patients: a multicentre observational study

OBJECTIVES

Opioid-induced respiratory depression (OIRD) and oversedation are rare but potentially devastating adverse events in hospitalised patients. We investigated which features predict an individual patient's risk of OIRD or oversedation; and developed a risk stratification tool that can be used to aid point-of-care clinical decision-making.

DESIGN

Retrospective observational study.

SETTING

Twelve acute care hospitals in a large not-for-profit integrated delivery system.

PARTICIPANTS

All inpatients ≥18 years admitted between 1 July 2016 and 30 June 2018 who received an opioid during their stay (163 190 unique hospitalisations).

MAIN OUTCOME MEASURES

The primary outcome was occurrence of sedation or respiratory depression severe enough that emergent reversal with naloxone was required, as determined from medical record review; if naloxone reversal was unsuccessful or if there was no evidence of hypoxic encephalopathy or death due to oversedation, it was not considered an oversedation event.

RESULTS

Age, sex, body mass index, chronic obstructive pulmonary disease, concurrent sedating medication, renal insufficiency, liver insufficiency, opioid naïvety, sleep apnoea and surgery were significantly associated with risk of oversedation. The strongest predictor was concurrent administration of another sedating medication (adjusted HR, 95% CI=3.88, 2.48 to 6.06); the most common such medications were benzodiazepines (29%), antidepressants (22%) and gamma-aminobutyric acid analogue (14.7%). The c-statistic for the final model was 0.755. The 24-point Oversedation Risk Criteria (ORC) score developed from the model stratifies patients as high (>20%, ≥21 points), moderate (11%-20%, 10-20 points) and low risk (≤10%, <10 points).

CONCLUSIONS

The ORC risk score identifies patients at high risk for OIRD or oversedation from routinely collected data, enabling targeted monitoring for early detection and intervention. It can also be applied to preventive strategies-for example, clinical decision support offered when concurrent prescriptions for opioids and other sedating medications are entered that shows how the chosen combination impacts the patient's risk.

Nurses' Ability to Recognize and Prevent Opioid-Induced Respiratory Depression: An Evidenced-Based Practice Project

Opioids are the primary therapy for acute postoperative pain, despite being associated with opioid-induced respiratory depression (OIRD). The purpose of this study was to improve nurses' knowledge, confidence, and ability to recognize, prevent, and treat OIRD in postoperative inpatients and evaluate the feasibility of using the Pasero Opioid-Induced Sedation Scale (POSS). Registered nurses completed three tools: (1) an Opioid Knowledge Self-Assessment, which was administered pre- and post-education; (2) a Confidence Scale, which was administered pre- and post-education; and (3) a POSS Perceptions and Usability Scale that was administered post-education. Nurses were educated on the POSS and then immediately following the training practiced by undertaking a patient assessment using the instrument. They then completed the POSS Perceptions and Usability Scale to rate their perception of the feasibility of using the POSS. Between preeducation and posteducation, participant knowledge increased in the following areas: recognizing opioid-induced side effects, dose selection, risk factors for oversedation, and information to make clinical decisions. However, there was a drop in scores when asked about knowledge of who is at risk for opioid-related side effects. These findings support our conclusion that OIRD education improves nursing confidence and knowledge. There was significant agreement between the nurse and subject matter experts POSS scores, indicating that this tool is easy to use.

The opioid epidemic from the acute care hospital front line

Prescription opioid use has risen steeply for over two decades, driven primarily by advocacy for better management of chronic non-cancer pain, but also by poor opioid stewardship in the management of acute pain. Inappropriate prescribing, among other things, contributed to the opioid 'epidemic' and striking increases in patient harm. It has also seen a greater proportion of opioid-tolerant patients presenting to acute care hospitals. Effective and safe management of acute pain in opioid-tolerant patients can be challenging, with higher risks of opioid-induced ventilatory impairment and persistent post-discharge opioid use compared with opioid-naive patients. There are also increased risks of some less well known adverse postoperative outcomes including infection, earlier revision rates after major joint arthroplasty and spinal fusion, longer hospital stays, higher re-admission rates and increased healthcare costs. Increasingly, opioid-free/opioid-sparing techniques have been advocated as ways to reduce patient harm. However, good evidence for these remains lacking and opioids will continue to play an important role in the management of acute pain in many patients.Better opioid stewardship with consideration of preoperative opioid weaning in some patients, assessment of patient function rather than relying on pain scores alone to assess adequacy of analgesia, prescription of immediate release opioids only and evidence-based use of analgesic adjuvants are important. Post-discharge opioid prescribing should be contingent on an assessment of patient risk, with short-term only use of opioids. In partnership with pharmacists, nursing staff, other medical specialists, general practitioners and patients, anaesthetists remain ideally positioned to be involved in opioid stewardship in the acute care setting.

Timing of Oversedation Events Following Opiate Administration in Hospitalized Patients

BACKGROUND

Unintended overdoses of opiate medications are potentially lethal events. Monitoring patients for oversedation is fundamental to ensuring safe use of opiates, and the timing of this evaluation is guided by the onset of action, time to max effect and duration of action of the opiate. The study's aim was to describe the timing of oversedation in relation to the predicted duration of action of the administered opiate.

METHODS

This study was conducted as a retrospective review of all opiate-related oversedation events during a 2-year period involving patients admitted to an urban teaching hospital.

RESULTS

Of the 53 opiate-related oversedation events evaluated, 47% occurred after the predicted maximal duration of action of the administered opiate.

CONCLUSION

Opiate-induced oversedation routinely occurs after predicted based upon duration of action. The study findings have profound implications upon nursing practice regarding duration of time required to monitor for opiate-induced oversedation.

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.