The Concentration Change Nobody Told the Pump
Six weeks ago pharmacy changed the standard norepinephrine bag from 4 mg/250 mL to 8 mg/250 mL. The laminated rate card for the old concentration is still taped to the top of the infusion pump. At 14:20 a 90 kg patient in septic shock is on norepinephrine ordered at 0.08 mcg/kg/min, running at 27 mL/hr; the bag was exchanged at 14:05. At 14:30 the MAP has risen from 68 to 104 mmHg, the heart rate has fallen from 96 to 44, and the patient is pale and diaphoretic. The hanging bag is labeled 8 mg/250 mL; you believe the previous one was 4 mg/250 mL.
1. Calculate what the patient was actually receiving before and after the bag change, and state your immediate action with the exact new rate.
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Concentrations:
- Old: 4 mg / 250 mL = 4,000 mcg / 250 mL = 16 mcg/mL.
- New: 8 mg / 250 mL = 8,000 mcg / 250 mL = 32 mcg/mL.
Delivered dose at 27 mL/hr:
- Old bag: 27 x 16 = 432 mcg/hr = 7.2 mcg/min = 0.08 mcg/kg/min - exactly the order.
- New bag: 27 x 32 = 864 mcg/hr = 14.4 mcg/min = 0.16 mcg/kg/min - double the order.
Immediate action:
- Halve the rate to 13.5 mL/hr (round to 13 or 14 per the pump library) to restore 0.08 mcg/kg/min.
- Tell the provider immediately and get a verbal order for the corrected rate.
- Assess the bradycardia: a reflex response to a doubled vasopressor is expected. If the patient is symptomatic or hypotensive, treat per protocol (for example atropine); otherwise monitor and expect improvement within minutes as the rate corrects.
- Stay at the bedside through the correction; recheck the MAP and heart rate every few minutes.
Roughly 25 minutes of double dosing is clinically significant in a septic patient whose baroreflex is already blunted.
2. Was this an individual error or a system error? Frame the response in just-culture terms, and list the concrete fixes you would propose.
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Both, and the system is the larger share. One person failed to compare the new bag label to the pump setting, but the environment made that comparison easy to skip: a laminated rate card for a discontinued concentration was mounted on the pump, and the pump library and the standard order set were not aligned at the changeover.
Fixes, in order of leverage:
- Remove every paper rate card and replace with a single current version; date-stamp it.
- Update the smart-pump drug library so a 32 mcg/mL bag cannot be selected with a rate calculated for 16 mcg/mL - build a hard or soft limit at the dose level.
- Barcode scanning at bag change so the pump reads the concentration off the label.
- Two-person independent double-check for every high-alert vasopressor bag change, with both people actually recalculating.
- Visual differentiation of the two concentrations during any transition period (distinct labels, a transition-only color band, and a posted notice in every room).
Scope note: an anesthesia technician may prepare, label, and spike medications under protocol, but administration and verification belong to the anesthesia professional or nurse. The technician's duty on discovering this is to speak up immediately, not to quietly adjust the rate.
3. What belongs in the event report and the handoff for this patient?
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Event report:
- A plain timeline: 14:05 bag change, 14:20 vitals, 14:30 vitals and discovery, the corrected rate and time, the provider notification and the response.
- The exact concentrations of both bags with lot numbers, the rates, and the calculated delivered dose in mcg/kg/min.
- Patient findings and treatment, including the bradycardia and any drug given.
- Names and roles of everyone involved, with the language kept factual and non-punitive.
- Whether the outdated rate card was attached to the pump - that detail drives the system fix.
Handoff (SBAR):
- Situation: vasopressor at twice the ordered dose for about 25 minutes, now corrected.
- Background: concentration standardization change six weeks ago with a lagging rate card.
- Assessment: current MAP, heart rate, rhythm, perfusion, and urine output; watch for rebound hypotension now that the dose is halved.
- Recommendation: continue at the corrected rate, recheck in 15 minutes, and confirm that no other pump in the unit still carries the old card.