How should the therapist interpret the lack of supernatant foam appearing during the shake test?

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Quizplus · Accepted Answer

Other tests for lung maturity have been developed; in the foam stability test, amniotic fluid is mixed with different volumes of 95% ethanol. When this mixture is shaken with air, a foam develops that can be seen for several hours at room temperature. If no surfactant is present, the foam will not appear or will appear only briefly, indicating the strong possibility of immature lungs. The shake test is not as specific as a low L:S ratio.

How Should the Therapist Interpret the Lack of Supernatant Foam