Fetal acoustic stimulation test (FAST).

Abstract

Objectives of this prospective interventional study was to evaluate the usefulness of fetal vibro-acoustic stimulation test (FAST) as a screening test for fetal surveillance, its predective values for fetal asphyxia and efficacy of FAST in converting false positive non reactive non stress tests (NST) to reactive ones; 423 high risk pregnant mothers; Had an initial NST followed by a FAST. A repeat NST was recorded in subjects who had an initial non reactive NST. If the mother delivered within 24 hours after FAST the fetal outcome was assessed; Main outcome measures were perception of fetal movements after FAST, results of NST before and after FAST, and 5 minute Apgar score at birth; FAST showed a sensitivity and specificity of 85 percentage and 90 percentage respectively taking, NST as the gold standard, and showed a 65 percentage positive predictive value for fetal asphyxia if delivered within 24 hours after the test. 47 percentage of initial non reactive NST results become reactive after FAST. Of the subjects who complained of absent or reduced fetal movements (n + 167) 67 percentage felt fetal movements after FAST, and 82.5 percentage of the total subjects (n + 423) noticed fetal movements after FAST. Fetal acoustic stimulation test is a reliable, cost effective screening test for fetal hypoxia. It should be introduced to Sri Lanka. and 90 respectively taking, NST as the gold standard, and showed a 65 positive predictive value for fetal asphyxia if delivered within 24hours after the test. 47 of initial non reactive NST results become reactive after FAST. Of the subjects who complained of absent or reduced fetal movements (n+167) 67 felt fetal movements after FAST, and 82.5 of the total subjects (n= 423) noticed fetal movements after FAST; Conclusion: Fetal acoustic stimulation test is a reliable, cost effective screening test for fetal hypoxia. It should be introduced to Sri Lanka