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Intravenous fluid resuscitation: was Poiseuille right?
Andrew D Reddick1, Julie Ronald, William G Morrison
1Emergency Department, Ninewells Hospital, Dundee DD1 9SY, UK. andrew.reddick@nhs.net
Aim:
To compare the flow rates of readily available intravenous infusion devices and to compare the effect of the addition of pressure or a needle-free intravenous connector device.
Methods:
Several intravenous devices with different characteristics had their flow rates determined under a standard set of conditions. The flow rates were then measured with the addition of a pressure bag to the system and then with a needle-free intravenous connector device. The flow rates and change in flow rates were then analysed.
Results:
The results showed a general agreement with Poiseuille's law. The needle-free connector slowed the rate of flow by up to 41.4% with the greatest effect on short, wide-bore devices. The addition of pressure had a greater effect on longer devices.
Conclusions:
Short, wide cannulae should be used when rapid fluid resuscitation is required. Needle-free devices should not be used when rapid fluid resuscitation is needed.
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