Opioid intoxication and overdose: Clinical sciences

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Introduction0:00–1:12

Opioid intoxication and overdose are terms used to describe the physiological and psychological changes that result from an excessive dose of opioids.
Now, opioids include heroin and powerful pain relievers like morphine, fentaNYL and oxyCODONE. Opioids can be taken through multiple routes including ingestion, inhalation, intravenous injection, as well as by transdermal patch.
Once in the body, they bind to major opioid receptors which are found in organs such as the brain, heart, blood vessels and gastrointestinal tract causing effects such as euphoria or dysphoria, meiosis or constricted pupils, bradycardia and hypotension and decreased bowel motility.
Leading to constipation. Sometimes opioid use can result in opioid overdose which can lead to severe respiratory depression, significant sedation, coma, and even death.
Now, if you suspect opioid intoxication or overdose, you should first perform an ABCD E assessment to determine if your patient is unstable or stable, if unstable, stabilize the airway, breathing and circulation.

Unstable patients1:12–4:37

Often you might need to intubate. Since unstable patients typically present with respiratory depression or apnea and require mechanical ventilation.
Next, provide supplemental oxygen, obtain IV access and if needed, administer fluids for volume resuscitation. Finally, don't forget to put your patient on continuous vital sign monitoring such as heart rate, BP and oxygen saturation.
Next, obtain a focused history and physical examination as well as point of care. Glucose at bedside, the history and physical are critical in these patients.
So if your patient is comatose or intubated, you should gather information from witnesses, friends, family members or emergency personnel history might reveal opioid use or a previous diagnosis of substance use disorder.
On the other hand, the physical exam typically shows signs of respiratory depression such as severely decreased respiratory rate, apnea and shallow breathing.
While oxygen saturation is usually below 90% due to severe respiratory depression. And some patients may also present with hypotension.
Next. These patients often have severely altered mental status.
They are typically unconscious or they might even experience seizures and don't forget to examine the patient's eyes because a patient with opioid intoxication or overdose will have meiotic pinpoint pupils that do not respond to changes in light also check bowel sounds which are typically decreased and look for evidence of substance use such as needle marks.
Finally get a point of care glucose measurement to rule out hypoglycemia, which can often mimic some symptoms of opioid overdose.
Patients with opioid intoxication or overdose typically have normal glucose levels. Now, here's a clinical pearl.
To keep in mind, labs are typically not needed to diagnose acute opioid intoxication or overdose. However, if you do order them, you might notice findings that support the diagnosis such as elevated creatine phosphokinase or CPK from rhabdomyolysis due to immobility or hypoxia.
Moreover, rhabdomyolysis can lead to acute kidney injury. And if this is the case, you might also see elevated B UN and creatinine levels.
Additionally, it's recommended to obtain a urine and blood toxicology screen in all patients that you suspect are having some type of overdose.
As there could also be additional agents compounding the presentation. These tests should not delay treatment if suspicion is high, all of these findings are highly suggestive of opioid overdose.
So you should immediately administer intravenous naloxone. This is a short acting opioid antagonist that competes with opioids at the opioid receptors.
And naloxone s binding affinity is highest to the mu opioid receptors. Specifically administer naloxone slowly every 2 to 3 minutes and assess the patient's response.

Opioid overdose4:37–6:14

Continue naloxone until the patient is awake and has a spontaneous respiratory rate of at least 12 or more breaths per minute.
If the maximal dose of naloxone does not cause any improvement, then consider an alternate diagnosis on the flip side. If your patient's respiratory function is improving, you can make the diagnosis of opioid overdose.
Keep in mind that your patient will start breathing spontaneously before they become fully alert. Now, some patients experiencing an overdose might require additional time and medication to recover.
So in this case, you can start an IV infusion of naloxone titrate to maintain adequate ventilation and consciousness and then gradually taper is tolerated during this period.
Monitor your patient to make sure they have no recurring sedation or respiratory depression, continue monitoring until they can breathe independently without naloxone or oxygen for at least 4 to 6 hours to help prevent relapse.
Patients with opioid use disorder should be offered the immediate opportunity to start maintenance treatment with medications like buprenorphine or methadone.
Another maintenance option to keep in mind is NALTREXONE, but it can only be started after there is no longer physical dependence on opioids, harm reduction steps to consider include prescribing naloxone to the patient for future emergency use and education about safer use practices.

Stable patients6:14–7:34

Finally, don't forget to refer them to a substance use and mental health specialist, peer support group and social support services if needed.
All right, now that we're done with unstable patients, let's go back to the ABCD E assessment and discuss the stable ones.
If the patient is stable again, obtain focused history and physical and point of care. Glucose history might reveal opioid use or a previous diagnosis of substance use disorder.
Additionally, you might hear from the patient's friends or relatives that the person was extremely euphoric, but at one point of the day, their mood switched and they became apathetic, agitated and dysphoric.
Also, your patient might report constipation, nausea or even vomiting. In contrast to individuals with opioid overdose, these individuals typically have adequate ventilation and perfusion and require no ventilatory support.
Similarly, they might have altered mental status or drowsiness but to a lesser extent. Additionally, physical exam could reveal decreased bowel sounds and evidence of substance use such as needle marks.
Finally, point of care, glucose will show normal glucose levels which rules out hypoglycemia. All of these findings are highly suggestive of intoxication.

Opioid intoxication7:34–8:28

So your next step is to assess the patient's pupillary constriction. If your patient has normal pupils consider alternative diagnoses such as sedative hypnotic or alcohol intoxication.
On the flip side, myotic pupils confirm the diagnosis of opioid intoxication. These patients typically do not require naloxone and their management primarily relies on monitoring until they reach the baseline mental status to help prevent relapse.
Patients with opioid use disorders should be offered the immediate opportunity to start maintenance treatment with medications like buprenorphine or methadone.
Another maintenance option to keep in mind is NALTREXONE, but it can only be started after there is no longer physical dependence on opioids, harm reduction steps to consider include prescribing naloxone to the patient for future emergency use and education about safer use practices.

Review8:28–10:59

Finally, don't forget to refer them to a substance use and mental health specialist, peer support group as well as social support services if needed.
All right, as a quick recap. If you suspect opioid intoxication or overdose in your patient, you should first perform an ABCD E assessment to determine whether they're unstable or stable.
If unstable, proceed with acute management focused history and physical as well as point of care, glucose at bedside to rule out hypoglycemia.
Once you suspect opioid overdose, administer naloxone and assess the patient's response if there's no improvement, consider alternative diagnoses.
However, if there is improvement, you can make a diagnosis of opioid overdose. Some patients with opioid overdose might require more time and medication to recover.
If so, you should start an IV infusion of naloxone and titrate it to maintain adequate ventilation and consciousness then gradually taper as tolerated.
Next, monitor your patient until they can maintain spontaneous breathing for at least 4 to 6 hours without naloxone or oxygen.
On the other hand, in stable individuals obtain focused history and physical and point of care glucose. Next, assess the patient pupils if they're normal, consider alternative diagnoses such as sedative and alcohol intoxication.
On the other hand, if their pupils are meiotic, you can make the diagnosis of opioid intoxication. Acute management primarily relies on monitoring until the patient reaches their baseline mental status to help prevent relapse.
After opioid intoxication or overdose patients with opioid use disorder should be offered maintenance treatment with buprenorphine or methadone in the short term with naltrexone as a maintenance option.
After physical dependence on opioids has ended harm reduction steps include providing naloxone to the patient for emergency use and education about safer use practices.
Also don't forget to refer them to a substance use and mental health specialist, peer support group as well as social support services if