Miniaturisation: La précision n'est pas au rendez-vous !

Accuracy of low-weight versus standard syringe infusion pump devices depending on altitude.

 

Blancher M  et Al. Scand J Trauma Resusc Emerg Med. 2019 Jul 11;27(1):65. doi: 10.1186/s13049-019-0643-1

 

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L'engouement pour la miniaturiation des équipements (PSE, Laryngoscope, Echographe) est grand. Encore faut il que la performance soit au rendez-vous. Ce n'est pas tout à fait le cas avec certains pousse-seringues, notamment en altitude. Ceci est très dommageable dès lors de la mise en oeuvre de perfusion d"amines pressives.

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BACKGROUND:

Intravenous drug infusions in critically ill patients require accurate syringe infusion pumps (SIPs). This is particularly important during transportation of critically ill patients by helicopter emergency medical services (HEMS), where altitude may influence device performance. Because weight is a real concern in HEMS, new low-weight devices are very appealing. The aim of this study was to compare infusion flow rates delivered by low-weight versus standard SIP devices, in the prehospital emergency medicine setting, at different altitudes.

METHODS:

We conducted a comparative bench study involving five SIP devices (two standard and three low-weight models) at 300, 1700 and 3000 m altitude. The primary endpoint was the flow rate delivered by SIPs for prespecified values. We used two methods to measure flow. The normative method consisted in measuring weight (method A) and the alternate method consisted in measuring instantaneous flow (method B).

 

RESULTS:

Using method A, no significant differences were found in median flow rates and interquartile range depending on device and altitude for a prespecified 10-mL/h flow. However, method B showed that low-weight SIPs delivered multiple sequential boluses with substantial variations (1.2-15.8 mL/h) rather than a prespecified continuous 5-mL/h flow. At 1700 m altitude, the interquartile range of delivered flows increased only for low-weight devices (p for interaction< 0.001).

CONCLUSIONS:

Despite satisfactory normative tests, low-weight SIPs deliver discontinuous flow with potential clinical implications for critically ill patients receiving vasoactive drugs. This study also highlights a thus far unknown negative impact of altitude on SIP function. We believe that normative requirements for SIP approval should be revised accordingly.