Automated lung sound analysis in patients with pneumonia.
OBJECTIVE
To determine whether objectively detected lung sounds were significantly different in patients with pneumonia than those in asymptomatic subjects, and to quantify the pneumonia findings for teaching purposes.


METHODS
At a community teaching hospital we used a multi-channel lung sound analyzer to examine a learning sample of 50 patients diagnosed with pneumonia and 50 control subjects. Automated quantification and characterization of the lung sounds commonly recognized to be associated with pneumonia were used to generate an "acoustic pneumonia score." These were examined in the learning sample and then prospectively tested in 50 patients and 50 controls.


RESULTS
The acoustic pneumonia score averaged 13 in the learning sample and 11 in the test sample of pneumonia patients. The scores were 2 and 3 in the controls. The positive predictive value of a score higher than 6 was 0.94 in the learning sample and 0.87 in the test sample. The sensitivities in the 2 groups were 0.90 and 0.78, and the specificities were 0.94 and 0.88, respectively. Adventitious sounds were more common in pneumonia patients (inspiratory crackles 81% vs 28%, expiratory crackles 65% vs 9%, rhonchi 19% vs 0%).


CONCLUSIONS
Our lung sound analyzer found significant differences between lung sounds in patients with pneumonia and in asymptomatic controls. Computerized lung sound analysis can provide objective evidence supporting the diagnosis of pneumonia. We believe that the lung-sound data produced by our device will help to teach physical diagnosis.
Murphy
Raymond L H
RL
Brigham and Women's/Faulkner Hospital, 1153 Centre Street, Suite 40, Boston MA 02130, USA. rmurphy@faulknerhospital.org
Vyshedskiy
Andrey
A
Power-Charnitsky
Verna-Ann
VA
Bana
Dhirendra S
DS
Marinelli
Patricia M
PM
Wong-Tse
Anna
A
Paciej
Rozanne
R
D000368:Aged; D001314:Auscultation / Q000379:methods*; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation / Q000379:methods*; D004867:Equipment Design; D005260:Female; D005387:Finland; D006764:Hospitals, Community; D006784:Hospitals, Teaching; D006801:Humans; D008297:Male; D015588:Observer Variation; D011014:Pneumonia / Q000175:diagnosis*; D012984:Software; D019023:Stethoscopes; D013664:Teaching Materials