Forehead is as sensitive as finger pulse oximetry during general anesthesia.
OBJECTIVE
To compare the performance of a forehead probe to a conventional finger pulse oximetry probe in anesthetized patients.


METHODS
Eighteen patients participated in the study. Each probe was connected to a Nellcor N-550 pulse oximeter. Anesthesia was induced and maintained with propofol. After intubation, the patients received air to achieve a steady-state of peripheral arterial oxygen saturation (SpO(2)). Ventilation was interrupted to induce a hypoxic state. As soon as one of the two SpO(2)'s decreased to 90%, the patients' lungs were ventilated with 100% oxygen. To evaluate the performance of the two pulse oximeters, time to the lowest (TL), time of recovery (TR) and lag times to beginning of SpO(2) decrease (Lag) were measured.


RESULTS
There were no significant differences in TL and TR between forehead and finger pulse oximetry under normal perfusion conditions during general anesthesia. When the axillary artery was compressed to mimic reduced peripheral perfusion, SpO(2) in the forehead decreased sooner than in the finger during hypoxia. The forehead and finger TLs were similar, however, TR was significantly longer in the finger.


CONCLUSIONS
The forehead SpO(2) sensor can be used as an alternative to the conventional finger sensor during general anesthesia.
Sugino
Shigekazu
S
Department of Anesthesiology, Sapporo Medical University School of Medicine, Sapporo, Japan.
Kanaya
Noriaki
N
Mizuuchi
Masahito
M
Nakayama
Masayasu
M
Namiki
Akiyoshi
A
D000768:Anesthesia, General; D005260:Female; D005385:Fingers / Q000098:blood supply*; D005546:Forehead / Q000098:blood supply*; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D010092:Oximetry; D010100:Oxygen / Q000097:blood*; D012039:Regional Blood Flow; D012121:Respiration, Artificial
D010100:Oxygen