Table 3.

Reliability and feasibility

	Per sensor
Initialization time	27 min
Total time until first displayed value	37.5 min [36/42]
Expected monitoring time after initialization	72 h
Actual monitoring time after initialization	37.9 h [23/71.3]
Real-time data display	32.5 h [16/62.4]
Percentage of real-time data display/expected monitoring time after initialization	45.1 %
Percentage of real-time data display/actual monitoring time after initialization	84.8 % [67.9/93.8]
Data gaps after initialization	5 h [1.9/8.3]
Percentage of data gaps/actual monitoring time after initialization	15.2 % [6.2/32.1]
Number of performed calibrations	9.5 [6/13]

Reasons for the 11,568 min (192.8 h) of data gaps	Percentage of data gaps 11,568 min (192.8 h)	Percentage of monitoring time 80,223 min (1337.1 h)
1 Poor sensor signal (%)	23.3	3.4
2 Sensor failure (%)	15.0	2.2
3 Processor line error (%)	10.9	1.6
4 Disconnection (%)	15.6	2.3
5 Pending after reconnection (%)	3.4	0.5
6 Calibration required (%)	27.8	4.0
7 Others (%)	4.0	0.6
Device-related reasons (1–3) (%)	49.2	7.2
Not device related (4–7) (%)	50.8	7.4

Reasons for 21 prematurely sensor removals	Number of sensors	Percentage of all sensors (%)	Percentage of removed sensors (%)
Sensors 72 h completed	10	32.3	–
Sensors removed prematurely	21	67.7	100
1 Accidentally	7	22.6	33.3
2 Poor sensor signal during measurement	7	22.6	33.3
3 Poor sensor signal immediately after initialization	1	3.2	4.8
4 MRI	1	3.2	4.8
5 Discharge	1	3.2	4.8
6 Death	2	6.5	9.5
7 Others	2	6.5	9.5
Device-related reasons (1–3)	15	48.4	71.4
Not device related (4–7)	6	19.4	28.6

n = 20 patients, 31 sensors

Results are expressed as median with interquartile range or as absolute numbers with percentages

MRI magnetic resonance imaging