Peristaltic wave amplitudes were also calculated as mean wave amplitudes during 10 wet swallows.
Differences for the parameters mean ICP, mean ICP wave amplitude and mean ICP wave latency were also determined during consecutive 6-s time windows.
In the present cohort, there were no differences between the management groups concerning the cardiac (CO, SV, HR and SVR), ABP (mean ABP, mean ABP wave amplitude) or CPP (mean CPP) parameters (Table 2).
Thus "elevated" ICP wave amplitudes were defined as: average of mean ICP wave amplitude ≥4 mmHg, combined with mean ICP wave amplitude ≥5 mmHg in ≥ 10% of the time recording during the period 23.00h - 07.00h [ 11].
Conversely, "low" ICP wave amplitudes were defined as: average of mean ICP wave amplitude <4 mmHg, combined with mean ICP wave amplitude ≥5 mmHg in <10% of the time recording during the same period [ 11].
On the contrary, there were minor differences between sensors in 8 of 10 patients regarding single wave pulse pressure amplitude (dP) and single wave latency (dT, i.e. rise time), and also with regard to the parameters mean ICP wave amplitude and mean ICP wave latency.
For each consecutive 6-s time window, cardiac output, mean ABP wave amplitude and mean ICP wave amplitude were computed, and exported to a spread sheet program for further analysis.
The RHI was calculated as follows: the ratio of the occluded arm's mean pulse wave amplitude at 90 150 s post-deflation to the mean amplitude of the same arm at baseline divided by the same ratio from the control arm, the quotient of which is multiplied by a proprietary baseline correction factor (Itamar Medical Ltd).
The levels of mean ICP wave amplitude s used for predicting shunt response in iNPH patients were independent of sensor location in 9 of 10 patients.
