The accidental overdose of opioids increased from the early 2000s, escalating to nearly 50,000 opioid-related deaths in 2018.1 Some of these overdoses are iatrogenic. A multiyear study from Ontario, Canada, reports 251 deaths specifically from Dilaudid (HYDROmorphone) due to oral and IV overdose.2 The Doctors Company claims database contains multiple cases of Dilaudid overdose resulting in morbidity and mortality.
These adverse events, specifically related to Dilaudid, are due to multiple reasons—including an erroneous understanding of the conversion ratio between IV Dilaudid and oral Dilaudid and the morphine milligram equivalent (MME) of Dilaudid.
A palliative care study found that 1 mg of IV Dilaudid is equivalent to 2.5 mg of oral Dilaudid and 11.46 mg of oral morphine.3
Conversion tables for commonly used oral opioids, including Dilaudid (HYDROmorphone), are readily available and may be easily referenced when prescribing and/or converting opioid dosage. One example is the oral Opioid Conversion Calculator provided by the Oregon Health Authority. Note that we have found a significant range in the equivalency of IV Dilaudid to morphine ranging from 1:5 to 1:8.
The following are current recommendations from UpToDate Lexicomp for dosing of IV Dilaudid and morphine:
According to the Centers for Disease Control and Prevention, higher dosages of opioids are associated with higher risk of overdose and death, and even relatively low dosages (20–50 MME per day) increase risk. Dosages at 50 MME per day double the risk of overdose compared to 20 MME.4
Appropriate pain management should ensure rapid and effective pain control without placing the patient at risk for harm. However, medical error reporting provides tragic examples of over-aggressive opioid administration as illustrated in the following case example.
A healthy opioid-naive 22-year-old man was admitted to hospital with acute upper back pain. Morphine was initially ordered at 1–5 mg intravenously every two hours as needed and was later increased to 5–10 mg intravenously every two hours as needed. Owing to poor pain control, an order was written in the evening to discontinue morphine and start HYDROmorphone at 5–10 mg intravenously every four hours as needed. The next morning, the patient was found without vital signs. Resuscitation efforts were unsuccessful.5
Alcohol, other opioids, and central nervous system depressants (sedative-hypnotics) can potentiate the respiratory depressant effects of Dilaudid. Seventy-seven percent of morbidity due to opioids occurs in the first postoperative day. Additional risk factors include patients who are over age 65 and those with comorbidities such as chronic obstructive pulmonary disease (COPD), kidney disease, congestive heart failure, and sleep apnea.6
Routine monitoring of vital signs by nursing staff may fail to recognize early signs of respiratory depression. Bradypnea is a poor predictor of desaturation and may be a late or absent finding,7 and pulse oximetry may not be an accurate monitoring tool for patients receiving supplemental oxygen.8 When pain is ameliorated and the patient falls asleep, he or she may slip unnoticed into respiratory depression and apnea.
The following cases from The Doctors Company closed claims files illustrate these points:
The Institute for Safe Medication Practices has compiled recommendations to help reduce patient harm from Dilaudid. We have added a few recommendations of our own:
To minimize narcotic-related respiratory depression, one large hospital group simplified narcotic administration by removing meperidine/promethazine from the hospital formulary and making Dilaudid the analgesic of choice but with rigorous controls. Hospital regulations now require an automatic advisory that the recommended Dilaudid dose is 0.2–0.5 mg IV whenever Dilaudid is ordered, a maximum dispensing limit of 1 mg per dose, reassessment of respiratory and pain status 15 to 30 minutes after a Dilaudid dose, and a focused education program for physicians and nurses emphasizing the relative Dilaudid-to-morphine ratio of 7:1.
The guidelines suggested here are not rules, do not constitute legal advice, and do not ensure a successful outcome. The ultimate decision regarding the appropriateness of any treatment must be made by each healthcare provider considering the circumstances of the individual situation and in accordance with the laws of the jurisdiction in which the care is rendered.