Dilatation Therapy and Demographic Characteristics Significantly Influence the Amount of Propofol for Therapeutic Endoscopic Retrograde Cholangiography

Table 3

Multivariable linear regression analysis to identify independent factors on the propofol dosage. Dilatation therapy, age, gender, intervention time, body mass index, platelet count, and bilirubin level were independently associated with the propofol consumption. Propofol dose served as the dependent variable. A logarithmic transformation was applied to all metric variables which showed a skewed distribution on the original scale. In case of more than 2 values for categorical variables a dummy transformation was performed. In a first step all factors were tested in univariate models. Subsequently, significant (p < 0.05) variables were entered into a multivariable model and a backward selection based on the Wald statistic was performed. Table 3 depicts the unstandardized coefficients with standard error, p-values, and 95% confidence interval.

	Unstandardized Coefficients		p-value	95,0% Confidence Interval for B
	B	Std. Error		Lower Bound	Upper Bound
(Constant)	169,980	57,570	,003	56,820	283,140
Dilatation therapy	49,102	19,731	,013	10,318	87,885
Age	-4,195	,561	,000	-5,297	-3,092
Intervention time	6,385	,342	,000	5,713	7,058
BMI	3,483	1,770	,050	,005	6,962
Platelets	,142	,060	,017	,025	,260
Bilirubin	-,055	,026	,036	-,107	-,004
Gender	46,160	17,440	,008	11,880	80,441