Opioid Toxicity (Nursing)


Learning Outcome

  1. Understand the risks and benefits of opioids
  2. List the presentation of opioid toxicity
  3. Identify risk factors of opioid toxicity
  4. Describe the nursing management of opioid toxicity
  5. Summarize the nurse care plan for a patient with suspected opioid toxicity

Introduction

Opioids and opiates together comprise a class of medications that are widely used primarily to control severe pain. The first-line medications for mild to moderate acute pain treatment are Acetaminophen or NSAIDs. If these first-line agents are not effective to control the pain, we can use medications that target different pathways like combinations of acetaminophen and opioid. Severe acute pain is treated with potent opioids.[1] Conventionally, the term opiates refer to natural compounds usually obtained from the poppy flower base. Opioids are synthesized by chemical processes. Opiates and opioids are among the most commonly abused substances throughout the world. Addiction to opioids and opiates has become a major health problem in the developed world since the 2000s, particularly in the United States.[2][3] About  21 to 29 percent of patients prescribed opioids for chronic pain misuse them and about 8 and 12 percent develop an opioid use disorder. It is estimated 4 to 6 percent who misuse prescription opioids transition to heroin. Opioid overdoses accounted for more than 42,000 deaths in 2016, more than any previous year on record. About 40% of opioid overdose deaths involved a prescription opioid.[4]

Nursing Diagnosis

The most common nursing diagnosis for opioid toxicity includes:

  • Impaired gas exchange related to decreased ventilatory rate
  • Ineffective breathing pattern
  • Ineffective airway clearance
  • Impairment in breathing
  • Activity intolerance
  • Risk for aspiration
  • Anxiety (mild, moderate, severe, panic)

Causes

Opioids are derived synthetically from generally unrelated compounds. Opiates are derived from the liquid of the opium poppy either by direct refinement or by relatively minor chemical modifications. Both opioids and opiates act on three major classes of opioid receptors: mu, kappa, delta, and several minor classes of opioid receptors like nociceptin, and zeta. Simplifying significantly, the mu receptors are thought to provide analgesia, respiratory suppression, bradycardia, physical dependence, gastrointestinal dysmotility, and euphoria. The kappa agonism can yield hallucinations, miosis, and dysphoria. The delta receptor likely has pain control and mood modulation effects, but some have suggested that mu agonism is necessary for the delta receptor to function strongly for analgesia.[5][6] The nociceptin receptor modulates brain dopamine levels and has clinical effects like analgesia and anxiolysis. The zeta receptor, also known as the opioid growth factor receptor, can modulate certain types of cell proliferation, such as skin growths, and is not thought to have many functions in the modulation of pain or emotion.[7][8] In high doses, opiates decrease the respiratory drive, causing apnea which leads to anoxic brain injury and death. 

Risk Factors

The most common risk factors associated with opioid misuse or addiction include:

  • Past or current substance abuse
  • Untreated psychiatric disorders
  • Young age
  • Unclear etiology of pain or exaggeration of pain 
  • History of legal problems
  • Psychological traumas 
  • Craving for prescription drugs

The most common risk factors associated with opioid overdoses include:

  • Comorbid mental and medical disorders
  • History of substance abuse, including alcohol
  • Methadone use
  • High opioid dosages
  • Benzodiazepine coprescriptions
  • Unemployment
  • Opioid naivety
  • Sleep apnea[9]

Assessment

Patients with opioid overdose typically have decreased responsiveness, hypopnea (abnormally slow respirations), slow speech, and constricted pupils. Constricted pupils may be seen in opioid tolerating individuals during active use even without the associated sedation and decreased respiratory drive issues.[10] Constipation is common, particularly in chronic consumers and the elderly. Opioids are thought to decrease bowel motility, but on occasion, bowel spasms can be produced such as with "codeine cramps." Naloxone is the treatment of choice for opioid-induced bowel spasms. If there is intravenous use, there can be "track marks." These are very small abrasion-type skin changes overlying veins, usually in the extremities but occasionally in the neck and other anatomic locations.[11]

Evaluation

The diagnosis of acute opioid poisoning is primarily clinical. In the overdose setting, hypopnea can progress to apnea. Naloxone is a mainstay of therapy, but the practitioner is warned that first-line treatment is control of the airway and rescue breathing. Adequate intravenous access is necessary so enough fluids and medication can be administered. An initial intravenous dose of 0.4 to 0.8 mg of naloxone will quickly reverse neurologic and cardiorespiratory symptoms.[12][13] although in some cases much higher doses are necessary, with case reports as high as 100 mg of naloxone required for successful resuscitation of a single overdose event (reference).[3] Bag-valve mask ventilation or similar intervention should be initiated immediately by the primary rescuer to restore oxygen supply to vital organs while other rescuers evaluate available methods of naloxone administration. Basic Life Support and Advanced Cardiac Life Support principles should be followed during the resuscitation of the opioid poisoned patient. Laboratory testing can include drug screening, but there is a widespread opinion that drug screening in this setting is not useful in making a timely diagnosis of opioid poisoning.[14] Drug screening is much more useful in screening for occult opioid use in settings such as pre-employment testing. When there is a disagreement between the patient and the provider regarding a drug screen result, gas chromatography and mass spectroscopy (GCMS) can provide a definitive answer regarding what was in the patient sample. In the United States, Medical Review Officers manage the data produced by employment drug testing.[15][16][17]

Medical Management

Traditional treatment of opioid/opiate addiction focuses on self-help in the setting of counseling and mentorship by addicts already successfully in recovery, with a focus on drug-free living. "Drug-free" in the minds of many in both recovery and treatment involves an absence of any chemicals including those prescribed by a medical provider. In the 2010s the concept of harm reduction became increasingly accepted by the mainstream of addiction treatment providers, which allowed for ingested medications to be taken, with an increased focus on objective patient outcome optimization. Chronic treatment of addicts with methadone (a full mu receptor agonist), buprenorphine (a partial agonist of mu receptors and Kappa antagonist), and Naltrexone (an opioid receptor antagonist) became more accepted. Increasing numbers of studies comparing various strategies of recovery and relapse suppression were seen in the literature. Concurrently, depot naltrexone injection for the enhancement of complete opioid avoidance became available. Each naltrexone injection lasts approximately 30 days. During that time, opioids are rendered ineffective by the effect of the naltrexone on the target receptors.[18][19] Disadvantages of naltrexone include difficulties in controlling acute pain in the setting of trauma and other acute medical issues. Depot naltrexone injection is contraindicated in the setting of chronic pain. Oral naltrexone is taken daily but is just about always ineffective if the patient controls their dosing schedule. Observed oral naltrexone administration controlled by a significant other may have a promise given recent literature regarding disulfiram in the treatment of alcoholism.[20][21][3]

Nursing Management

  • Assess breathing and oxygenation
  • Assess any respiratory distress
  • Provide oxygen if saturations less than 89%
  • Assess coughing ability and productivity
  • Listen to the lungs for crackles, wheezing, and airflow
  • Start one to two large bore IV's
  • Administer opioid reversal drugs as instructed
  • Place the patient on a cardiac monitor
  • Monitor the patient after opioid reversal
  • Notify the physician of suspected opioid overdose

When To Seek Help

  • Apnea
  • Respiratory distress
  • Unresponsiveness
  • Decreased level of consciousness 
  • Unstable vital signs to include low oxygen saturation

Outcome Identification

There is good evidence to support the use of an opioid for chronic pain but only with careful monitoring and education of the patient. For all patients, nurses are in the prime position to educate patients about the potential toxicity of opioids and the risk of addiction. Data show that in the short term, education and restriction of opioid prescriptions may be helping to avert the crises but the long-term data on whether it solves the addiction and physical dependence remain unknown.[22][23][24] (Level V)

Monitoring

It is suggested to use the following strategies to prevent any opioid prescription diversion:

  • In patients who tend to overuse medications, it is often prudent to dispense smaller quantities of medication and see patients more frequently
  • Pill counts is another strategy to promote adherence to the prescribed medication regimen
  • Ordering random urine toxicology and having a written contract to clarify the conditions under which opioids will be discontinued
  • Prescription Monitoring Programs. The physician can use this program to decrease diversion by determining when a patient is receiving a prescription from multiple providers.[25]

Coordination of Care

The opioids have created a major crisis in the US with reports of dozens of people dying almost every day. To ensure patient safety numerous guidelines have been developed to help healthcare workers mitigate the risks associated with opioid therapy. All healthcare workers who prescribe and dispense opiates are important partners in preventing the opioid overdose epidemic from getting worse. The guidelines all agree that the doses of opioids greater than 90 -200 mg of morphine equivalents per day should be avoided. Further, when starting or switching fentanyl patches to oral opioids, the doses should be reduced by 25-50%. The guidelines also recommend the use of opioid risk assessment tools, written agreements, and urine drug testing to mitigate the risks.[26][27] (Level III)

The pharmacist is perhaps in the ideal position to fight the opioid overdose epidemic. He or she should be the first to detect high prescription doses of opioids and speak to the healthcare provider before dispensing the drug. In addition, the pharmacist can check the drug database to determine if the patient is a drug abuser. Thirdly the pharmacist should inform the authorities if he or she deems that a healthcare worker is overprescribing narcotics each month.[27][28] (level III)

Health Teaching and Health Promotion

The discussion of the risk of the initial dose of outpatient oral opioids for acute pain has dramatically increased in intensity during the 2010s, particularly in pediatric and adolescent patients. Some locations in the United States mandate the written consent of the guardian of the patient prior to the initial outpatient opioid prescription. If there is a significant risk of misuse or overdose in the setting of chronic severe pain, some pain management doctors have found success with frequent appointments for prescriptions with very small numbers of doses, in some cases utilizing daily dosing of potent opioids to maintain the scrutiny intensity that particular patient requires for consumer safety, for example in the hospice patient with end-stage cancer who is actively using heroin. Many pain management doctors feel that an opioid overdose is not itself necessarily a mandate for ceasing all outpatient opioids, but it is certainly an event worth discussing at length with the patient and family regarding the risk of future overdose that this event predicts.[29] It is essential for patients consuming opioids of any kind to realize the enhanced danger opioids represent when co-ingested with substances that are GABA-ergic such as benzodiazepines, barbiturates, or alcohol.

Risk Management

The opioids have created a major crisis in the US with reports of dozens of people dying almost every day. To ensure patient safety numerous guidelines have been developed to help healthcare workers mitigate the risks associated with opioid therapy. All healthcare workers who prescribe and dispense opiates are important partners in preventing the opioid overdose epidemic from getting worse. The guidelines all agree that the doses of opioids greater than 90 -200 mg of morphine equivalents per day should be avoided. Further, when starting or switching fentanyl patches to oral opioids, the doses should be reduced by 25-50%. The guidelines also recommend the use of opioid risk assessment tools, written agreements, and urine drug testing to mitigate the risks.[26][27] (Level III)

It is important for a provider to carefully evaluate for chronic pain in any patient under consideration for referral to opioid recovery services. Improper referral of chronic pain patients without proper pain control contingency can result in severe patient distress and at times lead to a variety of medical complications. In the 2000s and 2010s, there was a dramatic increase in population-level opioid consumption in the United States, leading to a national discussion on how to better control distribution and use. Interdiction with control of physician behavior had some modest effects in the reduction of street availability of opioids with the following results (1) a concurrent rise in consumption of heroin, and (2) no improvement in the number of overall deaths from opioids from all sources combined. Also noted was the risk of theft of medications prescribed to the elderly and disabled, and steps were taken to educate these populations regarding those risks.[25]

Portugal had a severe problem with people addicted to these drugs and overdose deaths in the 2000s and early 2010s. Shortly after regulatory changes emphasizing drug decriminalization and referral to heavily government-subsidized treatment, Portugal documented a rapid and significant drop in deaths in the substance use disordered population. Portugal's example may provide a way forward for the United States with similar policy changes.[30]

The pharmacist is perhaps in the ideal position to fight the opioid overdose epidemic. He or she should be the first to detect high prescription doses of opioids and speak to the healthcare provider before dispensing the drug. In addition, the pharmacist can check the drug database to determine if the patient is a drug abuser. Thirdly the pharmacist should inform the authorities if he or she deems that a healthcare worker is overprescribing narcotics each month.[27][28] 

Discharge Planning

Discharge planning should be focused on preventing any further accidental episodes of opioid overdoses. All patients treated for a suspected opioid overdose should be discharged with a prescription for naloxone pen or naloxone nasal spray along with verbal and written instructions on its use. Patient teaching should be focused on instructing the patient to never take prescribed opioids in greater amounts than prescribed, to make the physician aware of any side effects, and to avoid taking opioids with alcohol, benzodiazepines, or muscle relaxants. [31]

Pearls and Other issues

It is important for a provider to carefully evaluate for chronic pain in any patient under consideration for referral to opioid recovery services. Improper referral of chronic pain patients without proper pain control contingency can result in severe patient distress and at times lead to a variety of medical complications. In the 2000s and 2010s, there was a dramatic increase in population-level opioid consumption in the United States, leading to a national discussion on how to better control distribution and use. Interdiction with control of physician behavior had some modest effects in the reduction of street availability of opioids with the following results (1) a concurrent rise in consumption of heroin, and (2) no improvement in the number of overall deaths from opioids from all sources combined. Also noted was the risk of theft of medications prescribed to the elderly and disabled, and steps were taken to educate these populations regarding those risks.[25]


Details

Nurse Editor

Lisa M. Haddad

Updated:

7/21/2023 11:10:25 PM

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