Use of microwave oven for determination of postmortem water volume of lungs

To determine if a microwave oven could be used to obtain accurate values of postmortem lung and blood water contents, we compared measurements made with a microwave oven to those obtained by drying the tissue in a vacuum oven set at room temperature. Tissue samples were obtained from 9 dogs and 10 sheep used for a variety of experiments resulting in a wide biological range of water fractions (0.74-0.88). The ratio of the values obtained by these two methods was 1.00 +/- 0.06 for dog tissues and 1.00 +/- 0.02 for sheep tissues. The use of a microwave oven for drying lung tissue and blood provides a measurement of lung water content that is not significantly different from values obtained by vacuum drying, but the microwave method requires only 1 h vs. several days or weeks.