Table 7

Accuracy of cumulative GRV for the 24 h prior to the GE study of (A) 150 ml and (B) 250 ml as a prediction of delayed GE as defined by gastric retention at 180 min ≥13%

		Delayed GE (TAV t_–24 ≥150 ml)		Total
		Normal GE	Delayed GE	Total
(A)
Delayed GE (retention at 180 min ≥13%)	Normal GE	9	2	11
Delayed GE (retention at 180 min ≥13%)	Delayed GE	4	7	11
Total		13	9	22

		Delayed GE (TAV t_–24 ≥250 ml)		Total
		Normal GE	Delayed GE	Total
(B)
Delayed GE (retention at 180 min ≥13%)	Normal GE	11	0	11
Delayed GE (retention at 180 min ≥13%)	Delayed GE	6	5	11
Total		17	5	22

(A) Sensitivity=0.636 (95% CI (0.346 to 0.870)); specificity=0.818 (95% CI (0.537 to 0.967)); positive predictive value=0.778 (95% CI (0.458, 0.959)); negative predictive value=0.692 (95% CI (0.423 to 0.893)); positive likelihood ratio=3.50 (95% CI (0.93 to 13.2)); negative likelihood ratio=0.44 (95% CI (0.19 to 0.1.02)).
(B) Sensitivity=0.455 (95% CI (0.194 to 0.735)); specificity=1.000; positive predictive value=1.000; negative predictive value=0.647 (95% CI (0.411 to 0.842)); positive likelihood ratio=undefined; negative likelihood ratio =0.
GE, gastric emptying; GEC, gastric emptying coefficient; GRV, gastric residual volume; TAV t_–24, total aspirate volume in the 24 h preceding the GE study.