Page 143 - Ultrasonography in Prehospital and Emergency Medicine - Rein Ketelaars

Prehospital chest ultrasound by a Dutch helicopter emergency medical service 141
51 (16%) examinations. Quality of imaging depended on body weight as shown in Figure 6.2. The differences are statistically significant (chi-squared p < 0.001).
For all 326 US examinations, a cardiac or pulmonary diagnosis was recorded as shown in Table 6.2. The cardiac US diagnoses are shown separately for trauma patients and for pa- tients in whom there was primary CPR.
Of the 59 (21%) patients transported to our hospital, a CXR and a CT scan were performed. Sensitivity and specificity of prehospital US for pneumothorax were 38% and 97%, respec- tively. Positive and negative predictive values were 90% and 69%, respectively. In the 15 pa- tients for whom US examinations were false negative, there were false-negative CXRs in 12 cases. Positive and negative test results are shown in Table 6.3.
The diagnosis of hemothorax was specifically excluded six times and confirmed only once by US examination. There were no false-positive and no false-negative US results.
Table 6.2 Ultrasound examination diagnoses and observations
Injury
Trauma patient n (%)
Primary CPR n (%)
Total n (%)
Cardiac
Asystole
Poor myocardial contractility Poor ventricular filling Pulmonary
Pneumothorax
Hemothorax
Pulmonary contusion
CPR, cardiopulmonary resuscitation.
Table 6.3 Comparison of ultrasound
transported to the Radboud university medical center
26 (8) 9 (3) 9 (3)
25 (9) 2 (1) 2 (1)
22 (7) 8 (2) 3 (1)
– – –
for
48 (15) 17 (5) 12 (4)
25 (9) 2 (1) 2 (1)
in patients
examination
with
CT
pneumothorax
Test result
CT +
CT –
Total
US+ 9 1 10 US– 15 34 49 Total 24 35 59
CT, computed tomography; +, positive test result; –, negative test result.
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