Biomedical subjects

Tatsuo Tanita

Publications and source records attributed to Tatsuo Tanita.

4 recordsLinked to original sources

PubMed2005

[Lung cancer in elderly patients: lung cancer and lung function].

The incidence of bronchogenic carcinoma is increasing as life expectancy rises. With increase in the aged population in Japan, the number of patients suffering from lung cancer and candidates for lung resections are increasing. In this paper, the author lists up indispensable procedures for diagnosis, namely, lung function tests, unilateral pulmonary arterial occlusion test and exercise tolerance test. The cut-offs for identifying candidates for elderly patients for lung resections can be applied the same cut-offs for younger patients. Also the author indicates the importance of postoperative management for lung lobe resections. In order to prevent postoperative problems such as congestive heart failure that might be a fetal complication, the most useful check values after the lung surgery for elderly patients are rate of transfusion and urine volume. In conclusion, when elderly patients assert their rights to undergo lung surgery, we, the thoracic surgeons, should reply their requests under the equal quality of safe surgery as that for younger patients. Besides, it is desirable that even elderly patients, over 80 years old, who undergo lung surgery should guarantee their quality of daily life after surgery.

Age Factors↗

PubMed2004

[Preoperative evaluation for lung resection using right ventricular hemodynamic functions by unilateral pulmonary arterial occlusion test].

We performed a unilateral pulmonary arterial occlusion (UPAO) test for the preoperative evaluation of right ventricular functions as a loading test in patients undergoing a lung resection without cardiac complications preoperatively. We investigated the relationship between changes in right ventricular hemodynamic functions and postoperative cardiac complications, namely right heart failure or arrhythmia. To evaluate the right ventricular hemodynamic function test, we measured the mean pulmonary arterial pressure, cardiac index, right ventricular ejection fraction end-diastolic volume, and stroke volume before and during the UPAO test using the thermodilution method, and calculated the total pulmonary vascular resistance and right ventricular stroke work indexes. The incidence of postoperative cardiac complications was not related to the changes in the total pulmonary vascular resistance index. However, the postoperative cardiac complications were common in patients whose right ventricular end-diastolic volume index was increased by more than 20% during the UPAO test. These results suggest that the changes in the right ventricular end-diastolic volume index during the UPAO test can predict postoperative cardiac complications in patients undergoing a pulmonary resection.

Arrhythmias, Cardiac↗

PubMed2004

Review of preoperative functional evaluation for lung resection using the right ventricular hemodynamic functions.

Surgery for patients with lung cancer diminishes their lung functions, due to removal of their lung lobes. Therefore, thoracic surgeons have to consider postoperative lung function of patients. In this review, we explained recent approaches of estimation of postoperative lung function by spirometrical and also pulmonary circulatory measurement values. The most common and simple way to estimate postoperative conditions for patients who undergo lung resections is calculated by numbers of segments that are removed by surgery. However, these methods are not so accurate when the patients have chronic obstructive pulmonary disease. Another method for estimating postoperative conditions using right heart catheterization is a unilateral pulmonary arterial occlusion (UPAO) test. Applying this method, surgery related deaths have been decreased. Since, UPAO test mimics the postoperative state by occluding the pulmonary artery prior to lung surgery, it is supposed to be very accurate. Recently, a novel method to estimate postoperative right heart reserve functions was developed. Using this method, postoperative right heart failures can be anticipated prior to lung resections. In this review, we explain these kinds of methods to prevent impairment of postoperative quality of life.

Heart Failure↗

PubMed2003

Endothelial barrier strengthening by activation of focal adhesion kinase.

Endothelial cell barrier (EC) properties regulate blood tissue fluid flux. To determine the role of endothelial-matrix interactions in barrier regulation, we induced cell shrinkage by exposing confluent endothelial monolayers to hyperosmolarity. The dominant effect of a 15-min hyperosmolar exposure was an increase in the trans-endothelial electrical resistance, indicating the induction of barrier strengthening. Hyperosmolar exposure also increased activity of focal adhesion kinase and E-cadherin accumulation at the cell periphery. Concomitantly, the density of actin filaments increased markedly. In EC monolayers stably expressing constitutively active or dominant negative isoforms of Rac1, the actin response to hyperosmolar exposure was enhanced or blocked, respectively, although the response in trans-endothelial resistance was unaffected, indicating that the endothelial barrier enhancement occurred independently of actin. However, in monolayers expressing a kinase-deficient mutant of focal adhesion kinase, the hyperosmolarity-induced increases in activity of focal adhesion and peripheral E-cadherin enhancement were blocked and the induced increase of electrical resistance was markedly blunted. These findings indicate that in EC exposed to hyperosmolar challenge, the involvement of focal adhesion kinase was critical in establishing barrier strengthening.

Animals↗