Review Question - QID 217294

This patient with a history of substance use disorders who was found to be minimally arousable with pinpoint pupils is most likely suffering from an opioid overdose. Opioids cause decreased respiratory rate, decreased tidal volume, decreased temperature, and decreased blood pressure.

Opioids act on almost every organ system and can result in significant pathophysiologic derangements if an overdose occurs. In the central nervous system, opioids cause analgesia, euphoria/dysphoria, sedation, cough inhibition, and miosis. In the cardiovascular and pulmonary systems, opioids can cause respiratory depression, vasodilation, and hypotension. In the gastrointestinal system, opioids can cause constipation, increased biliary sphincter tone, nausea, and vomiting. In the genitourinary system, opioids can cause urinary retention and may also prolong labor. Together, these changes will result in decreased responsiveness and coma during an overdose.

Vivolo-Kantor et al. studied the rate of opioid overdoses and found that they increased nationwide, especially in urban centers. They argue that knowing the signs and symptoms of opioid overdose is critical for all healthcare providers.

Figure A presents sets of vital signs as answer choices including respiratory rate (RR), tidal volume (TV), temperature (Temp), and blood pressure (BP).

Incorrect Answers:
Answer 2: Decreased respiratory rate, decreased tidal volume, normal temperature, and decreased blood pressure would be seen in patients who take sedative drugs such as benzodiazepines; however, these drugs would not cause pupillary constriction.

Answer 3: Increased respiratory rate, normal tidal volume, increased temperature, and increased blood pressure would be seen in patients who take sympathomimetic drugs such as cocaine; however, these drugs would present with pupillary dilation and agitation. Pupils are dilated but still reactive with sympathomimetics.

Answer 4: Normal respiratory rate, normal tidal volume, increased temperature, and increased blood pressure would be seen in patients who take anticholinergic drugs such as tricyclic antidepressants; however, these drugs would present with pupillary dilation, flushing, and dry skin. Pupils are both dilated and generally minimally responsive with anticholinergic toxidromes.

Answer 5: Normal respiratory rate, normal tidal volume, normal temperature, and normal blood pressure would be seen in patients who are exposed to cholinergic drugs such as pesticides; however, these drugs are not drugs of abuse and would present with diarrhea, vomiting, diaphoresis.

Bullet Summary:
Opioid overdose presents with decreased respiratory rate, decreased tidal volume, decreased temperature, and decreased blood pressure.