Individuals with OUD have high rates of emergency department (ED) utilization.155-157 These high rates of utilization suggest that ED visits may be an opportunity to engage individuals in evidence-based OUD care and promote harm reduction. A small but growing body of evidence suggests that ED-based initiation of OAT increases engagement and retention in treatment.158-160 See Evidence Review for a review of available research related to ED-initiation of buprenorphine/naloxone. A brief summary of the supporting evidence follows.

Over half (60.4%) of the 10,455 people who had a fatal or non-fatal overdose in BC from January 1, 2015 to November 30, 2016 had utilized ED services in the past year.157 In 2017, 70% of the people who died from drug toxicity in the Vancouver Coastal Health region had visited an ED in the previous year.489 

Emergency department-initiated buprenorphine/naloxone is associated with:

• Higher treatment engagement and fewer days of self-reported unregulated opioid use after 30 and 60 days, compared to screening and brief intervention or screening, brief intervention, and facilitated referral to community-based treatment158,161
• Significantly higher likelihood of receiving OAT compared to clonidine159
• Successful follow-up with outpatient clinics (54%) and successful retention in OAT (buprenorphine/naloxone) at 6 months (35%)160
• Lower ED utilization at 6 months160
• Cost effectiveness relative to both referral and brief intervention162

A small number of case studies (N=3) have shown that individuals can be inducted onto buprenorphine/naloxone in the ED immediately following naloxone reversal of an opioid overdose, without serious adverse events.163

Emerging evidence demonstrates that low-dose initiation in the ED is feasible and may improve OAT retention in comparison to traditional induction.490 

To increase the chances of engaging ED patients with OUD in OAT, the BCCSU and BC Patient Safety and Quality Council worked together to launch the Learning about Opioid Use Disorder in the Emergency Department Collaborative (LOUD in the ED). The program developed three key resources: a Tool for Emergency Department Buprenorphine/naloxone Induction, a webinar series,  and two new modules for the Provincial Opioid Addiction Treatment Support Program (POATSP). While this appendix provides a general overview of buprenorphine/naloxone initiation in EDs, prescribers are encouraged to refer to these resources for detailed guidance. 

A4.1 General Considerations

• General screening and eligibility assessment guidance for buprenorphine/naloxone initiation guidance applies to ED-initiation.
• Whether an eligible ED patient chooses to initiate OAT or not, supporting connections to OUD care and treatment in this setting should be prioritized. This may include:
  • Provision of take-home naloxone
  • Emergency department initiation of buprenorphine/naloxone (low-dose or traditional induction)
  • Provision of take-home doses (“bup-to-go”) in order to facilitate a home induction
  • Referral to a community prescriber or specialist to initiate other OAT (e.g., methadone, slow-release oral morphine, or injectable OAT)
  • Referral to community-based support services
  • Education on harm reduction and provision of harm reduction supplies
• For a comprehensive decision support tool containing a step-by-step pathway for guiding emergency department inductions, see the Decision Support Tool for Emergency Department Buprenorphine/naloxone Induction by LOUD in the ED.

A4.2 Screening

Patients who present with overdose, withdrawal, or other negative consequences from unregulated opioid use (e.g., cellulitis, mental health concerns) may be suitable for ED-initiation of buprenorphine/naloxone. However, broader screening of ED patients for OUD is also encouraged where possible, since potential candidates for OAT initiation may not be limited to those who present to the ED with opioid-related emergencies.  Emergency department-initiation of buprenorphine/naloxone may be appropriate if the patient has opioid use disorder and if there is sufficient clinical information to indicate suitability for ED-initiation. 

Eligibility

While individual program requirements may vary, eligibility for a traditional buprenorphine/naloxone induction should be met, including:

• Diagnosed opioid use disorder
• Informed consent
• Clinical Opiate Withdrawal Scale (COWS) score of >12 (at least moderate withdrawal)
• Adequate time since last opioid use, to prevent precipitated withdrawal:
  • ≥12 hours for short-acting opioids (e.g., heroin, oxycodone, hydromorphone)
  • ≥24 hours for intermediate-acting opioids (slow-release oral morphine) and confirmed or suspected fentanyl1
  • 48–72 hours for long-acting opioids (e.g., methadone)

It is advised that patients who use fentanyl complete a minimum of 24 hours of abstinence prior to traditional induction regardless of the COWS score. Support the patient to sustain the pre-induction withdrawal period for as long as tolerable, since patients who have been using fentanyl may experience unexpected precipitated withdrawal symptoms up to 48 hours after last use.153 If the patient prefers not to experience moderate withdrawal prior to induction, consider initiating a low-dose induction (see Appendix 3 for more information). 

If a significant delay is anticipated until adequate withdrawal is achieved, consider “bup-to-go”  or prescribe a home induction instead, with follow-up from their primary care provider or referral to a community OAT clinic, or rapid access addiction clinic. “Bup-to-go” may be prescribed as a low-dose or tradtional induction. See Home Induction in Appendix 3.

Patients presenting to the ED may require laboratory and other diagnostics, including a urine drug test and pregnancy test, as needed, for their care management; however, if a patient declines recommended additional testing, this should not be a barrier to receiving further care and is not required for a diagnosis of OUD.

A specialist (e.g., Addiction Medicine Consult Team, RACEapp, or the 24/7 Addiction Medicine Clinician Support Line) should be consulted in the following situations:

• Pregnancy
• Allergy to buprenorphine/naloxone
  • Currently on OAT, particularly a long-acting opioid (e.g., methadone)
• Unless the patient requests it, changing OAT medications in the ED is usually not indicated
• Concurrent withdrawal/intoxication from one or more sedative (e.g., benzodiazepines, alcohol, z-drugs)
• Severe respiratory or liver dysfunction

A4.3 Monitoring

Following a traditional buprenorphine/naloxone induction 

Pre-induction in ED: COWS administered by nurse or MD every two hours until score is >12 

During induction ED: COWS administered by nurse or MD pre-dose for all doses and 1-hour post first three doses 

Changes in the COWS score over time can guide how patients are titrated. At the discretion of the treating clinician, patients who still report discomfort due to withdrawal symptoms and are under-dosed may be titrated up to the suggested maximum first day dose more quickly. Always consider the possibility of precipitated withdrawal if a patient’s COWS score is worsening. 

Buprenorphine/naloxone administration does not discontinue once a patient’s COWS score is <12. Patients should continue to receive buprenorphine/naloxone, either in the ED or as a take-home dose, until they no longer experience withdrawal symptoms or reach the maximum first day dose (see below for dosing).

Note: Initiation can occur in a low acuity area that can accommodate frequent patient assessment and medication administration. No cardiorespiratory monitoring is required.

A4.4 Initiation

Following a traditional buprenorphine/naloxone induction 

If the patient is in sufficient withdrawal upon presentation to the emergency department, likely to reach significant withdrawal shortly, or would benefit from a short observation stay, start an emergency department initiation. Initiation should follow the general guidance (see Appendix 3.).  Initiation can be entirely completed in the ED or continued after discharge with provision of additional doses to take home if the patient’s ED stay is shorter than the time required for full induction. 

Always offer non-opioid medications to alleviate withdrawal symptoms prior to the first dose or during the first few doses. Keep in mind these medications may decrease the COWS score. Options include (if no contraindication to individual medications):

• Acetaminophen (650-975mg po q6h PRN)
• Ibuprofen (400mg po q6h PRN)
• Loperamide
• Ondansetron or dimenhydrinate, as per standard dosing
• Clonidine (0.1-0.2mg po q6h PRN)

Home initiation (prescription or “bup-to-go”) may be appropriate in the following situations:

• Patient preference
• Patient is not in sufficient withdrawal upon presentation to the ED and anticipated time to moderate withdrawal is lengthy

In these cases, buprenorphine/naloxone may be prescribed or dispensed to complete a home initiation.  In addition, medications to relieve withdrawal may be prescribed, and patient information material (including an induction information sheet) should be provided. See Home Induction, above, for more information.

Buprenorphine/naloxone dosing should start with 2mg/0.5mg buprenorphine/naloxone SL and can be titrated up to a target total first day dose of 12mg/3mg to 16mg/4mg. If the patient’s COWS score has consistently decreased receiving 2mg/0.5mg per hour, it may be appropriate to increase to 4mg/1mg per hour, once the patient has reached 8mg/2mg total of buprenorphine/naloxone, with no signs of precipitated withdrawal. 

While the product monograph recommends a target first day dose of 12mg/3mg, clinical experience suggests that higher doses (up to 16mg/4mg) can be administered safely and may be necessary to adequately address withdrawal symptoms. The clinician’s selection of total first day dose should be guided by their organization’s paper or electronic order sets, patient comfort, and their comfort level in administering a higher dose. As with any medical treatment, exceptions may be made at the discretion of the treating clinician, after carefully balancing the risks benefitts of a given approach.

Table 28. Example Initiation Protocol Starting at 12pm

A4.5 Discharge Planning

Discharge planning should start as soon as the patient agrees to initiate buprenorphine/naloxone. The following provides guidance for what could be included in discharge planning, with each patient’s plan tailored to their needs and circumstances.

• Give the patient a take-home naloxone kit and provide training on how to administer naloxone
• Consolidate the patient’s doses received during initiation to once daily and provide discharge prescriptions
  • If initiation has not been completed, provide remaining doses to complete initiation at home
  • Consider providing PRN additional buprenorphine/naloxone doses (either bup-to-go from the ED or as a prescription) to alleviate withdrawal symptoms (e.g., 4 x 2mg)
  • Provide a bridging prescription of 2–7 days of buprenorphine/naloxone, depending on access to follow up care
  • Provide non-opioid medications to alleviate withdrawal symptoms
• Refer the patient to continuing OAT care (OAT Clinics Accepting New Patients)  and encourage the patient to pre-book a follow-up OAT appointment, either with their usual community prescriber or designated OAT clinic  
• Refer to outreach support services as required or requested (if available)
• Provide the patient with information on available community resources such as harm reduction facilities (e.g., supervised consumption sites), community-based healthcare clinics, psychosocial support services (e.g., housing, nutrition), and educational materials (e.g., Opioids: A Survivors Guide)
• Send referral directly to OAT clinic, including a copy of their chart or discharge summary containing total buprenorphine/naloxone dose provided and time of last dose, and consider providing additional copy for referral to patient
  • Consider creation of referral pathways, including standard referral letters to receiving clinics
• Discuss with patient any support people who should be alerted of the treatment plan (e.g., staff at supportive housing)
• If home induction is planned, provide patient with induction information sheet
  
   

References

1.   Although fentanyl has a rapid and intense onset with a relatively short duration of action (1–2 hours), it has a long terminal half-life, likely due rapid distribution into the body’s tissues due to its lipophilic nature. 
2. ”Bup-to-go” refers to buprenorphine/naloxone kits (usually 3-day supply) dispensed from the ED to facilitate home initiation without requirement of prescription to fill at a pharmacy.  Dispensation uploaded to PharmaNet as standard practice.
3. Note that low-dose induction is increasingly used by community OAT providers, to avoid the need for patients to experience moderate withdrawal. See Low-dose Induction for more information.
4. A variety of resources may be available in each hospital and community to support linkage to care and reduce barriers to retention in treatment, such as patient navigators, social workers, rapid access addiction clinics, and peer-led organizations such as the BC Association of People on Opiate Maintenance.
5. Cost of medication may be a barrier some patients. If required to ensure coverage, fax a signed OAT referral to BC Mental Health and Substance Use Services, along with a signed Application for PharmaCare Plan G form, or connect patient to a community prescriber who can provide support with paperwork and ongoing care.

The above appendix was developed to support clinical practice using a different methodology from the process utilized for the main body of the guideline. 

The clinical guidance provided in the appendix has been derived through guideline committee consensus following iterative discussions in reference to existing evidence and national and international evidence-based clinical practice guidelines. 

The content presented in the appendix is also informed by the opinion of expert reviewers, personal communication with study authors, and a review of position papers and practice bulletins issued by recognized addiction medicine professional organizations and authorities. In addition, where appropriate, Health Canada-approved drug product monographs, and previous and current guidance from the College of Physicians and Surgeons of BC (CPSBC) and Health Canada were consulted to ensure compliance with provincial and national safety regulations and standards for practice.