Dynamic respiratory mechanics in intact anesthetized hamsters.

A system for measuring parameters of ventilation and respiratory mechanics in intact anesthetized hamsters was developed. Means +/- SD of five weekly measurements in eight hamsters were 0.68 +/- 0.09 ml for tidal volume, 45 +/- 14 breaths.min-1 for respiratory frequency, 29.3 +/- 10.4 ml.min-1 for minute ventilation, 0.301 +/- 0.080 ml.cmH2O-1 for dynamic compliance, 0.435 +/- 0.151 cmH2O.ml-1.s for inspiratory resistance, 0.311 +/- 0.101 cmH2O.ml-1.s for expiratory resistance, and 0.334 +/- 0.096 cmH2O.ml-1.s for average resistance. The standard deviations of five consecutive measurements of these parameters on the same day were typically 10% of the corresponding mean values suggesting that acute changes as small as 10% can be detected in a study of similar size. The corresponding value for five single measurements on different days at weekly intervals was 30%. We believe that this system yields reasonable and repeatable measurements, and, because it is atraumatic, it can be used in chronic studies of diseases in hamsters and other small animals.