Metoclopramide CRI: Checking Another Technician's Bag
A 10 kg spayed female Beagle is hospitalised on the second day after an exploratory laparotomy for a small-intestinal obstruction. She is still vomiting intermittently, so the veterinarian orders metoclopramide as a constant-rate infusion at 1 mg/kg/day IV, carried in 0.9% sodium chloride running at a maintenance rate of 20 mL/hr. At 14:30 the day-shift technician adds 5 mL of metoclopramide 5 mg/mL to a 500 mL bag, labels it, and hangs it at 15:00 with the pump set at 20 mL/hr. You take over the case at 17:00; the pump has delivered about 40 mL. The vomiting has settled, but the dog is now restless, panting and pacing the run, and will not settle on her blanket. The ward nurse assumes this is post-operative pain. The bag is still hanging and the infusion is still running.
1. Verify the infusion the previous shift prepared. Show the calculation, state whether the bag is correct, and explain how it might account for the dog's behaviour.
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Ordered dose: 1 mg/kg/day × 10 kg = 10 mg/day = 0.417 mg/hr.
What is in the bag: 5 mL × 5 mg/mL = 25 mg in roughly 505 mL, giving about 0.0495 mg/mL (0.05 mg/mL if you ignore the added volume).
What is being delivered: 0.0495 mg/mL × 20 mL/hr = 0.99 mg/hr ≈ 23.8 mg/day = 2.4 mg/kg/day.
The bag is roughly 2.4 times the ordered dose. That matters clinically: metoclopramide at supratherapeutic doses causes restlessness, pacing, panting, agitation and extrapyramidal signs in dogs - an exact match for what you are seeing, and a better fit than pain in a dog whose surgery was two days ago and whose vomiting has settled. Pain should still be assessed, but the arithmetic has to be addressed first.
A second check worth doing: confirm the vial strength (5 mg/mL is common, but 5 mg/mL and 10 mg/mL products both exist) and read the label against the order rather than against the previous technician's handwriting.
2. The nurse suggests simply slowing the pump so the dog receives the correct milligram dose. Evaluate that plan and describe what you would do with the bag and the patient over the next 30 minutes.
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The plan is wrong, for two reasons. To deliver 0.417 mg/hr from a 0.0495 mg/mL solution you would need 8.4 mL/hr - the drug dose would be right, but the fluid rate would fall from the prescribed 20 mL/hr to 8.4 mL/hr. The fluid order exists for its own reasons (maintenance after major abdominal surgery), so you cannot trade one order for another. The bag would also then hang for about 60 hours, far beyond any reasonable in-use limit for a spiked bag.
Sequence:
- Stop the infusion and tell the veterinarian now - do not wait for the end of the shift.
- Re-make the bag correctly: 10 mg/day ÷ 24 = 0.417 mg/hr; at 20 mL/hr that is 0.0208 mg/mL × 500 mL = 10.4 mg, i.e. 2.08 mL of 5 mg/mL. Label with drug, total dose, final volume, rate, date, time prepared and initials.
- Recheck the patient: heart rate, respiratory rate and effort, temperature, mentation, and whether the pacing settles once the drug is stopped. Ask the veterinarian to assess pain independently so a real problem is not dismissed as drug effect.
- Record the volume already received (about 2 mg of metoclopramide), the time the infusion was stopped, the notification and the response.
At 2.4× for two hours the total exposure is modest and signs should resolve, but that is the veterinarian's call to make with the facts you supply.
3. This is the third CRI error in the practice in two months. What is your professional responsibility now, and what process change would you propose?
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The immediate duty is to the patient, then to honest documentation. Never adjust, backdate or 'tidy' the record to make the error disappear; write what happened, when, what was given, what the patient did, who was notified and what was changed. Most practices also require a incident report, and the veterinarian decides what, if anything, is disclosed to the owner - withholding a harmful error is an ethical problem, but disclosure is the clinician's conversation, not something to improvise at the desk.
The pattern matters more than the individual. Three errors in two months points at the system, not at three careless people. Reasonable fixes: a standard concentration table for common CRIs posted at the pharmacy bench; an independent second-person check of every CRI calculation, signed on the label; pre-printed labels showing drug, dose, bag volume and pump rate so the arithmetic is visible to whoever takes over; and a non-punitive review of all three events to find the common step. Framing the review as patient safety rather than blame is what gets errors reported early instead of hidden.