[Survey of patients with obstructive ventilatory disturbance by spirometry and cooperation among departments in university hospital].

The purpose in this study was to reveal the number of chronic obstructive pulmonary diseases (COPD) among the patients who examined spirometry in Shinshu University Hospital. We prospectively picked up the patients over 40 years of age who showed obstructive ventilatory disturbance on spirometry who examined for about 6 months, and send the results with the comments to introduce the patients to the department of respiratory medicine to the doctors who ordered spirometry. Spirometry was examined in 1,657 patients, and 246 patients (14.8%) who showed their FEV1/FVC < 70%. Among 246 patients, 177 patients were ordered spirometry from the departments (83.6%; pre-operative spirometry) except for respiratory medicine. Seventy-two of 177 patients (40.7%) were introduced to the department of respiratory medicine following the comments, and 43 and 13 patients were diagnosed as COPD and asthma, respectively. These findings suggest that laboratory technologist can contribute to the early intervention of COPD by supporting corporation among departments in hospital.

[Usefulness of a new sheet-like apparatus (SD-101) for screening of sleep apnea syndrome].

Polysomnography (PSG) is the gold standard for the diagnosis of sleep apnea syndrome (SAS). However, PSG is not suitable as a first-line examination for all people suspected as having SAS because PSG requires hospitalization. Therefore, it is hoped that a simple examination can be developed which is available for use in the home. The present study evaluated the usefulness of a new sheet-like apparatus (SD-101) which is equipped with 162 pressure sensors for SAS diagnosis. One hundred patients hospitalized for PSG were simultaneously examined using the SD-101, and 25 patients, who underwent both PSG and SAS screening with MORPHEUS R, were also studied. The SD-101 is inserted between a sheet and the bed, and detects pressure from many points on the patient's body as it presses against the bed. Continuous changes of these pressure points are converted to respiratory movement. A very close correlation was seen between the apnea hypopnea index of PSG and a respiratory disturbance index of SD-101 (r=0.90), although there was a significant but lower correlation between data obtained PSG and MORPHEUS R(r=0.84). The sensitivity and specificity of the examination using SD-101 were 98.2% and 55.8%, respectively. These findings suggested that a new apparatus, SD-101, may be useful for the screening of SAS.

Compound muscle action potentials during repetitive nerve stimulation.

When using repetitive nerve stimulation to examine neuromuscular transmission, the change in compound muscle action potential (CMAP) size is usually assessed by measurement of negative-peak or peak-to-peak amplitude. Technological developments now allow automatic measurement of CMAP area, but some patients show increment of CMAP amplitude and decrement of CMAP area. This study systematically analyzed the changes in these CMAP parameters in 23 neurologically healthy subjects. CMAPs were recorded when the ulnar nerve was stimulated at frequencies of 1, 2, 5, 10, 20, 30, and 50 HZ (five pulses per train). CMAP amplitude showed significant increment within a train when stimulus frequency was above 5 HZ (probably due to increased muscle-fiber conduction velocity), whereas CMAP area hardly changed at any frequencies. Measurement of CMAP area produces less ambiguous results than amplitude measurement in repetitive nerve stimulation studies.

Peripheral nerve function in patients with familial amyloid polyneuropathy after liver transplantation.

To evaluate the therapeutic efficacy of liver transplantation in patients with ATTR Val30Met familial amyloid polyneuropathy (FAP), were repeatedly examined the neurophysiological function of peripheral nerves in nine patients. The maximal motor and sensory conduction velocities (MCV and SCV) of the ulnar and tibial nerves, size of compound muscle action potential (CMAP), terminal latency of CMAP, skin temperature of extremities, CVR-R, blood pressure, heart rate, and Schellong's test were examined before and every 6 months after the operation. Although there were no changes in CVR-R, blood pressure, or heart rate, the skin temperature of foot and hand increased soon after surgery and did not decrease during the period of observation. The temperature-adjusted MCV of tibial nerve gradually increased, but the MCV of ulnar nerve showed no change. The temperature-adjusted tibial nerve SCV worsened slightly soon after transplantation and remained at that level in the distal part. The ulnar nerve SCV worsened and subsequently improved. Liver transplantation is very effective for halting the progression of this type of FAP, but the recovery of peripheral nerve function in patients seems to be very slow and limited, especially the function of large diameter myelinated fibers.