Background: Internal thoracic impedance (ITI) measurement is a sensitive method for detecting preclinical pulmonary edema and pleural effusion.
Objectives: To investigate the efficacy of this non-invasive method for detecting early pleural effusion among geriatric patients and to monitor increased ITI during its resolution.
Methods: This prospective, controlled study was conducted between July 2012 and August 2015. The study comprised 70 patients aged 65 to 94 years; and 39 of the patients had pleural effusion. ITI was measured continuously with a RS-207 monitor. The predictive value of ITI monitoring was determined based on a total of eight measurements taken at 12-hour intervals over 84 hours.
Results: As a result of medical treatment, the median ITI of the study group increased from 31 (interquartile range [IQR] 28-33 ohms) to 41 ohms (IQR 38-41 ohms; P < 0.001) compared to non-significant changes in the control group. Average respiratory rate (per minute) in the study group decreased from 29 (IQR 28-34) to 19 (IQR 18-20).
Conclusions: ITI monitoring is efficient for diagnosis and for ongoing clinical evaluation of the treatment of elderly patients with pleural effusion. Timely treatment may prevent serious complications of effusions avoiding extended hospitalization.