Changes in ventilatory pattern and arterial oxygen saturation during spinal anaesthesia in man.
Using a respiratory inductive plethysmograph and a pulse oximeter, we investigated the changes in the respiratory pattern and peripheral oxygen saturation (SpO2) of the finger before and during spinal anaesthesia in 20 surgical patients. The rib cage contribution to the tidal volume (%RC) increased significantly from before (20.4 +/- 4.3%) to during spinal anaesthesia (30.4 +/- 4.8%). However, in those patients who fell asleep 60 min after subarachnoid injection of a local anaesthetic, %RC returned to the preanaesthetic value (23.0 +/- 5.9%). Finger SpO2 increased significantly during spinal anaesthesia, but the femoral arterial oxygen saturation did not change. The authors conclude that spinal anaesthesia increases %RC in conscious patients. However, the increment of %RC does not cause a major change in arterial oxygen saturation.
Yamakage
M
M
Department of Anesthesiology, Sapporo Medical College, Japan.
Namiki
A
A
Tsuchida
H
H
Iwasaki
H
H
D000328:Adult; D000775:Anesthesia, Spinal; D005260:Female; D005385:Fingers / Q000098:blood supply; D006801:Humans; D008297:Male; D008875:Middle Aged; D010092:Oximetry / Q000295:instrumentation; D010100:Oxygen / Q000097:blood*; D010991:Plethysmography / Q000295:instrumentation; D015656:Respiratory Mechanics / Q000502:physiology*
D010100:Oxygen