[Pulmonary function tests in home medical care].

Home medical care for the aged has become important with the increasing population of elderly people in Japan. Home oxygen therapy (HOT) is a representative treatment for aged patients with chronic obstructive pulmonary diseases (COPD) or sequelae of pulmonary tuberculosis. In order to provide appropriate and safe home medical care, the pulmonary function tests need to be performed easily and simply at home. These tests include a pulse oximeter for arterial blood oxygen saturation monitoring in HOT, a peak flow meter or a handy-type spirometer for air way monitoring in asthmatic patients and a handy-type monitor for screening patients with sleep apnea syndrome (SAS). In using a pulse oximeter, the users need to keep in mind that the case is sometimes severe even though the oxygen saturation values are in the normal ranges, and also that, when oxygen saturation is low, high concentrated oxygen exposure sometimes deteriorates hypercapnia in patients with type II respiratory failure. A peak flow meter is not suitable for air way monitoring in patients with COPD or small air way diseases. The handy-type monitor for SAS needs to be improved not to interfere with the patient's natural sleep, and also to provide more simple analysis programs. Doctors should educate patients to go to hospital to see a doctor and to undergo close examinations whenever unexpected abnormal values are obtained. Equipment which can provide high quality test results with easier maneuver ability and analysis needs to be developed in the future.