INFLUENCE OF PULSE OXIMETER LOWER ALARM LIMIT ON THE INCIDENCE OF HYPOXEMIA IN THE RECOVERY ROOM

Citation
At. Rheineckleyssius et Cj. Kalkman, INFLUENCE OF PULSE OXIMETER LOWER ALARM LIMIT ON THE INCIDENCE OF HYPOXEMIA IN THE RECOVERY ROOM, British Journal of Anaesthesia, 79(4), 1997, pp. 460-464
Citations number
21
Categorie Soggetti
Anesthesiology
ISSN journal
00070912
Volume
79
Issue
4
Year of publication
1997
Pages
460 - 464
Database
ISI
SICI code
0007-0912(1997)79:4<460:IOPOLA>2.0.ZU;2-B
Abstract
In a prospective, randomized study, we have investigated the effects o f two arbitrary pulse oximeter lower alarm limit (LAL) settings (90%=g roup 90, n=320 and 85%=group 85, n=327) on the incidence of hypoxaemia in the recovery room. in group 90, we calculated the theoretical effe ct of elimination of transient episodes of low pulse oximeter oxyhaemo globin saturation (Sp(O2)) by introducing a time delay between the ons et of the alarm condition and triggering of the alarm. When only hypox aemic episodes lasting more than 1 min were included, Sp(O2) less than or equal to 90% occurred in 11% of patients in group 90 and in 20% in group 85 (relative risk (RW) 1.84, confidence interval (CI) 1.26-2.69 ; P<0.01). Hypoxaemia less than or equal to 85% occurred in 2% of pati ents in group 90 and in 6% in group 85 (RR 3.10, CI 1.32-7.28; P<0.01) . In group 90, 1007 alarms (33% false) occurred, whereas in group 85, 395 alarms (28% false) occurred. Introducing a theoretical delay of 15 s in group 90 between crossing the alarm threshold and triggering the alarm would have reduced the number of alarms by 60%. The results of the study suggest that decreasing the alarm limit in an attempt to red uce frequent false alarms may lead to an increase in more relevant epi sodes of hypoxaemia and setting the LBL at 85% cannot be recommended r outinely. Introducing a 15 s delay in group 90 would reduce the number of alarms by the same amount as changing the LAL from 90% to 85%.