Monitor alarms are a major burden on both patients and staff in intensive care units. We compared alarm rates from three different monitor systems (Hewlett Packard (HP), Kontron Instruments (KI), Marquette-Hellige (MH)) in a tertiary neonatal intensive care unit. Monitors were used in random order on three consecutive days over 8 h each in 16 preterm infants (median gestational age at birth 29 wk (range 24-34), age at study 18 d (8-53), weight at study 1,160g (595-1,430)). Alarms were classified as true or false using flow sheets based on continuous observation of both the patient and related parameters. There was one alarm every 9 min of monitoring. The median number of true alarms did not differ significantly between systems, being 28 per 8 h (range 9-87) for HP, 26 (3-81) for KI, and 30 (5-135) for MH. The median number of false alarms differed widely, with the HP system generating 32 (7-77) such alarms per 8 h, compared to 8 (0-19) for KI and 15 (2-32) for MH (p < 0.01 HP vs KI and MH, p < 0.05 KI vs MH). These differences between systems were mainly due to differences in pulse oximeter and transcutaneous PO2 monitor alarm rates.
Conclusions: In conclusion, this study shows marked differences between both parameters and manufacturers in the frequency with which false alarms occur. It may provide a basis from which reductions in alarm rates can be sought.