EFFECT OF DIGITAL BLOCK ON SPAO2, LAG TIME AND HEIGHT OF PLETHYSMOGRAPHIC WAYE OF PULSE OXIMETER BY SIMULATED SHOCK

K TAVAKKOL, H SOLTANI NEZHAD, SEYED JALAL HASHEMI

Abstract


Introduction. Pulse oximetry is impaired by hypotention and peripheral vasoconstriction. Digital block may cause to increase tissue perfusion and improve the parameters of pulse oximetry. The purpose of this study was to investigate the effect of digital block on SPa02, lag time and height of plethysmographic wave of pulse oximeter by simulated shock in upper extrimity.
Methods. In an experimental study, 34 Paitents under general anesthesia and elective surgery were selected. Lag time and height of pletysmographic wave and SPa02 had been measured in two fingers shocked by cooling, elevation of hand and inflation of cuff; then, compared to opposite middle finger as control. shocked Middle finger were blocked by lidocaine 2% and these parameters were measured in the 15th and 20th minutes after digital block. Data analysis was performed by SPSS using ANOVA.
Results. Mean height of plethysmographic wave in blocked finger was signihcontly taller than shocked and control fingers in the 15th minute (respectively, 16.9±6, 10.8 ± 4. 3,10.7 ± 4.3, P < 0.05) and the 20th minute afters digital block (21.1 ± 5.8, 11.8 ± 4.3, 11.2 ± 3.9, P < 0.05). There were not significalt differences between three fingers in lag time and SPa02.
Discussion. This study documents effect of digital block, undergoing shock condition in improving the parameters of pulse oximetry.

Keywords


Pulse oximetry, Digital Block, Lidocaine, lag Time, Simulated Shock