Applicability of pocket ultrasound during the first trimester of pregnancy

To determine the applicability of pocket ultrasound as a complementary method for clinical evaluation during the first trimester of pregnancy.

A prospective cross-sectional study was conducted with 86 pregnant women attended in an emergency. The same operator performed the first examination with pocket device Vscan (General Electric, Vingmed Ultrasound, Horten, Norway) and then repeated the exam using a traditional handset high resolution Voluson 730 Expert (General Electric Healthcare Ultrasound, Milwaukee, WI, USA). Data were recorded with individual diagnoses by means of yes/no binary as the visualization of variables: gestational sac, embryo, embryo heartbeat, topical or ectopic pregnancy. Concordance was calculated using the kappa coefficient with its respective 95% confidential intervals (CI).

There was no disagreement between the methods when compared the pocket and conventional ultrasounds. The best comparative result between the devices was as the visualization of the embryo heartbeat with kappa coefficient of 0.84 (95% CI 0.76 to 0.89). However, the pocket ultrasound had a low correlation for diagnosis of ectopic pregnancy, with kappa coefficient of -0.02 (95% CI -0.23 to 0.19). The smaller structure visualized and studied using the pocket ultrasound was an embryo of 3.4 mm.

The method of pocket ultrasound has the potential to become a complementary and easy access for diagnostic tool in obstetric patients during the first trimester. However, in ectopic pregnancy cases the diagnosis should be realized by conventional ultrasound.