Auteur: Alexandra Gerlach, Simon Franz
Date: 16.02.2018
Last change: 15.02.2018
Particularly relevant for ASV 1.1The Heart-Lung Interaction Index (HLI) is a value for the variation of the plethysmogram amplitude, which reflects how much ventilation interacts with hemodynamics. High variation means high interaction. In the following situations, HLI should not be used or used with caution.
The likelihood of incorrect values may increase if you are using ASV® 1.1.
In active, spontaneously breathing patients, the value shown for the calculated HLI may be negative.
The formula for calculating HLI is as follows:
HLI = 100*(POPmax – POPmin)/((POPmax + POPmin)/2)
POPmax is the maximum amplitude of the plethysmogram within the same breath and POPmin is the minimum. In a spontaneously breathing patient, the POPmax and POPmin (one measured during inspiration and one during expiration) may be inverted, resulting in a negative HLI value. In general, patient values may range anywhere between approx. -10% and +30%.
When using the INTELLiVENT-ASV PEEP Controller with HLI activated, and in particular with ASV 1.1, the alarm Check INTELLiVENT PEEP limit setting may be triggered if the following criteria are met:
The problem should be solved by turning off the alarm and deactivating the HLI checkbox, which will cause the alarm to reset.
Please see your device’s Operator’s Manual for information on causes for this alarm and the appropriate action.
HLI sensitivity is decreased when:
Relevant devices: HAMILTON-G5/S1 (sw v2.6x)