Accuracy of a peristaltic finger-type infusion pump during hyperbaric oxygen therapy

PURPOSE: To evaluate the accuracy of a peristaltic finger-type pump during hyperbaric oxygen therapy (HBO). METHODS: Using two examples of one type of infusion pump, we evaluated its accuracy at 2 ATA (atmospheres absolute) by measuring the actual volumes pumped at given time points (flow rate) and comparing these data with the corresponding data obtained at 1 ATA. RESULTS: There was no significant difference in flow rates between 2 and 1 ATA. In terms of accuracy, the present pump was superior to the syringe pump tested in our previous study. Under our conditions, the ambient pressure might have acted equally on the inlet and outlet sides of the infusion line, which may explain the lack of effect of 2 ATA on flow rates. This is not the case with a syringe pump, and the difference in flow-generating mechanisms may help explain the different results obtained in our two studies. CONCLUSION: The present type of pump could be used during HBO (at 2 ATA) with the same accuracy as at 1 ATA. Whether the ambient pressure can affect pump input and output (peristaltic-pump infusion line) or only pump output (syringe type) may determine whether accuracy suffers under HBO conditions.