Related Experiment Video
Updated: Jul 2, 2026

Modified Langendorff Perfusion for Extended Perfusion Times of Rodent Cardiac Grafts
Published on: June 14, 2024
Prolonged time to alarm in infusion devices operated at low flow rates
Roy Ilan1, Robert A Fowler, Niall D Ferguson
1Department of Medicine, Queen's University and Kingston General Hospital, Kingston, ON, Canada. ilanr@kgh.kari.net
Objective:
To evaluate the time to occlusion alarm for peristaltic infusion devices used in Toronto adult critical care units.
Design:
Cross-sectional study.
Setting:
Biomedical engineering departments of four Toronto teaching hospitals.
Subjects:
Twenty peristaltic infusion devices (five Sigma 8000-plus, five Graseby 3000, five Baxter Colleague, and five Alaris 7230B).
Interventions:
None.
Measurements:
Time to occlusion alarm at flow rates of 2, 10, and 100 mL/hr at a full range of available pressure thresholds for occlusion detection, and with commonly used tubing sets.
Main Results:
At default (mid-range) pressure thresholds, mean (SD) time to occlusion alarm was 0.3 (0.1) min at a flow rate of 100 mL/hr, 2.3 (0.5) min at a flow rate of 10 mL/hr, and 11.7 (3.1) min at a flow rate of 2 mL/hr.
Conclusions:
Time to occlusion alarm in peristaltic infusion devices is long at low flow rates. Patients receiving important medications with short half-lives at low flow rates could experience clinically important interruptions in treatment. Time to occlusion alarm at high flow rates is short, which could lead to excessive alarms and "alarm mistrust" by clinical staff.
Related Concept Videos
Drug Accumulation During Multiple Dosing: Intermittent IV Infusions
Errors occurring during blood pressure monitoring
Several factors...
Determination of Multiple Dosing Parameters: Steady-State, Minimum and Maximum Concentrations
One-Compartment Model: IV Infusion
The one-compartment model for IV infusion uses mathematical equations to describe the rate of change in drug quantity in the body. At steady-state or infusion equilibrium, the drug input...
