A comparison between low-flow leak test and oxygen flush leak test.
OBJECTIVE
The clinical efficacy of two methods of preanesthetic leak test,namely the oxygen flush leak test (OFLT) and the low-flow leak test (LFLT), was compared regarding their ability to detect leakage in the anesthesia circuit and their accuracy.


METHODS
Examinees comprised 16 staff anesthesiologists and 7 physicians undergoing anesthesia training at our institution. They performed the two leak tests on anesthesia machines with some intentional leaks (0.1-1.0 l.min(-1)). The leakage detection rates (LDR) were analyzed by the chi(2)-test. The ability to detect leaks was measured by recording how many leaks were detected by 50% (LDR(50)) and 95% (LDR(95)) of the examinees.


RESULTS
The LDRs in the two tests were significantly different (chi(2)- analysis, P < 0.0001). Both LDR(50) and LDR(95) for the LFLT (0.23 and 0.41 l.min(-1), respectively) were smaller than the values for the OFLT (0.37 and 0.82 l.min(-1), respectively). The sensitivity and specificity of the LFLT (0.97 and 0.84, respectively) were higher than those of the OFLT (0.78 and 0.80, respectively).


CONCLUSIONS
The LFLT was found to be superior to the OFLT regarding leak detection and reliability. We therefore recommend the LFLT for preanesthetic leak testing.
Tokumine
J
J
Department of Anesthesiology, Faculty of Medicine, University of the Ryukyus, 207 Uehara, Nishihara, Okinawa 903-0215, Japan.
Iha
H
H
Okuda
Y
Y
Nitta
K
K
Ishigaki
K
K
Oshiro
M
M
Shimabukuro
T
T