6.3 Titration, Baseline Dosing, and Breakthrough Pain

6.3 Titration, Baseline Dosing, and Breakthrough Pain

Once the right opioid is chosen (6.1), CHPN items become arithmetic plus timing. Uncontrolled pain on a hospice service is more often underdosed basal, missing rescue, or rescue given before peak, than a need for an exotic drug. This section is how you titrate.

Around-the-clock for continuous pain

If pain is present most of the day, treat it as continuous. Continuous pain needs around-the-clock (ATC) dosing so the plasma level does not crash every afternoon. Extended-release morphine, oxycodone, or hydromorphone every 12 hours (some morphine ER products are every 24 hours) is the usual oral basal. When ER products are unavailable or the patient is in a rapid titration, immediate-release opioid every 4 hours by the clock can serve as the basal, then convert the 24-hour total to an ER regimen once the dose is stable.

End-of-dose failure — pain that returns like clockwork before the next ER dose — is not mysterious breakthrough. It means the basal milligrams or the interval is wrong. Increase the ATC dose or, less often, shorten the interval. Do not keep adding PRN tablets at hour 11 and call the basal adequate.

Do not crush, chew, or open extended-release tablets or capsules unless the specific product is labeled for that manipulation. Crushing ER morphine dumps 12 hours of opioid at once: a burst of sedation and respiratory depression, then a stretch of no coverage. If the patient can no longer swallow ER tablets, change the route (concentrated oral solution, subcutaneous infusion) rather than pulverizing the ER product.

Breakthrough and incident pain: short-acting rescue

Breakthrough pain is a transient flare on top of otherwise controlled basal pain. Incident pain is breakthrough with a trigger: a dressing change, a transfer, coughing on bone mets. Idiopathic breakthrough has no obvious trigger. All three are treated with a short-acting opioid, not with an extra ER tablet and not with acetaminophen when the patient is already at the acetaminophen ceiling.

For predictable incident pain, pre-medicate with oral IR about 60 minutes before the event (or a parenteral dose closer to the event) so the peak coincides with the dressing change.

The 10–15% rule

The standard CHPN-level breakthrough dose is 10–15% of the total 24-hour opioid dose (TDD). Some protocols and NCCN language use 10–20%; learn 10–15% as the exam default, and know that 20% sits at the aggressive end of the same idea. Use the same opioid as the basal when possible so you are not converting on the fly at 2 a.m.

Worked example the blueprint expects you to do in under a minute:

• Morphine ER 30 mg every 12 hours
• Basal TDD = 30 × 2 = 60 mg oral morphine / 24 h
• Breakthrough = 10% of 60 = 6 mg, and 15% of 60 = 9 mg
• Order morphine IR 6–9 mg (practically 5–10 mg oral solution or tablet, per available strengths) for breakthrough

If the basal is parenteral, the rescue is parenteral. Ten percent of a 24 mg/day subcutaneous morphine infusion is a 2.4 mg subcutaneous bolus (often rounded to a measurable 2–3 mg).

q1h versus q4h: follow the peak, not a superstition

Redosing frequency is about time to peak, not a single sacred interval.

The dangerous pattern is stacking oral IR every 15 minutes because the nurse is thinking in IV time. Three oral doses before the first one has peaked land together an hour later. Conversely, telling a patient in a pain crisis that oral morphine can only be repeated every 4 hours means they sit through three hours after peak with no legal dose. CHPN logic: do not redose before peak; after peak, you may redose if pain remains severe, using the agency protocol (often q1h oral, q15–30 min parenteral).

After three or more breakthroughs in 24 hours, raise the basal

A rescue dose is a probe. If the patient needs three or more effective breakthrough doses in 24 hours, the ATC dose is too low (assuming the pain is opioid-responsive and there is no new acute complication such as fracture or cord compression). Convert PRN usage into the new basal.

Method:

1. Add scheduled milligrams used in 24 hours to PRN milligrams used in 24 hours. That sum is the new TDD.
2. Give the new TDD as ATC (usually split every 12 hours for ER products, or as a continuous subcutaneous infusion).
3. Recalculate rescue as 10–15% of the new TDD.
4. Continue a bowel regimen; titration is not complete if constipation is ignored.

Worked example, extending the 30 mg q12h case:

• Basal: morphine ER 30 mg q12h = 60 mg
• Rescue used: morphine IR 8 mg four times = 32 mg
• Four rescues is more than three, so the basal is inadequate
• New TDD = 60 + 32 = 92 mg
• Practical new basal: morphine ER 45 mg q12h = 90 mg (closest clean ER split)
• New breakthrough = 10–15% of ~90 mg = 9–14 mg oral IR (practically 10 mg)

If yesterday's PRNs were taken for incident pain only (one dressing change, one transfer) and basal nights are comfortable, you may pre-medicate for the incident rather than inflating the 24-hour basal. The exam still wants you to know the three-rescue rule for uncontrolled background pain.

Rapid titration versus a patch

When pain is a crisis, titrate with IR oral or parenteral doses at peak intervals, total the milligrams that worked, then build the basal. Do not start a fentanyl patch to titrate. Patches are for stable requirements (6.4). Do not crush ER morphine to mimic an IR dose.

Oral IR onset is often 15–30 minutes, with peak near 60 minutes; subcutaneous and intravenous routes are faster and are preferred when the patient cannot swallow or when you need a quicker peak. Once the 24-hour requirement is known, convert IR-only ATC into ER or into a continuous subcutaneous infusion using the same TDD, then keep a 10–15% rescue.

Titration is a loop: ATC covers the day, rescue covers the flare, three-plus rescues rewrite the ATC, new rescue is 10–15% of the new TDD, reassess at peak.