Table 2.

Multiple linear regression model to predict the percent change in mean arterial blood pressure following tourniquet deflation.

Predictive variable	Partial regression coefficient(95 % Confidence interval)	P-value
Percent change in LF/HF	−0.035 (−0.049, −0.020)	<0.001
Age (years)	0.184 (−0.221, 0.588)	0.365
Spinal anesthesia-induced hypotension	−0.791 (−5.828, 4.245)	0.754
Duration of tourniquet inflation (min)	0.069 (−0.343, 0.482)	0.738
Intercept	−25.342 (−57.424, 6.741)	0.119

Coefficient of determination (R²)=0.340, adjusted R²=0.286, P<0.001. LF/HF, low-to-high frequency ratio of heart rate variability. No multicollinearity was detected.