[Intraoperative right-to-left shunting induced by supine position in simultaneous lung resection with repair of atrial septal defect].

This report describes the case of a 49-year-old woman, who was suffered severe hypoxemia attributable to right-to-left shunting through an atrial septal defect (ASD) during the combined surgery for lung cancer and ASD in supine position. Right-to-left shunting has been reported to occur after lung resection but not during it. According to our continuous measurement of pulmonary arterial pressure and oxygen saturation, changes in hemodynamics during lobectomy in supine position was supposed to differ from that in lateral position, which may contribute to right-to-left shunting. A combined lung resection with heart surgery was performed safely and resulted in preventing postoperative complications induced by ASD.

[Preoperative assessment of myocardial ischemia in thoracic surgery for lung cancer].

BACKGROUND: Morbidity of myocardial ischemia in the thoracic surgery for lung cancer has been reported in the literatures, although, the risk of myocardial ischemia is not well identified preoperatively. OBJECTIVES: The aim of this study was to describe the prevalence of severe coronary stenosis in the thoracic surgery for lung cancer. METHODS: From January 2004 to December 2006, data were collected concerning 175 consecutive patients underwent lung resection for lung cancer. Prior to the surgery, we performed coronary angiography on the patients with either ischemic change in the exercise electrocardiogram (ECG) testing or comorbid conditions (current or previous smoking, hypertention, diabetes mellitus, hyperlipidemia or history of chest pain). RESULTS: Fifty-eight (33%) patients underwent coronary angiography. Coronary stenosis was detected in 19 patients (10.9%), including 6 patients (3.4%) with severe stenosis. These 6 patients received percutaneous coronary intervention or coronary artery bypass grafting prior to the lung resection, which resulted in no incidence of perioperative myocardial ischemia. Three of 6 patients with severe stenosis were negative for ischemic changes in exercise ECG testing. CONCLUSION: The prevalence of severe coronary stenosis is 3.4%, which is supposed to indicate the risk of perioperative myocardial ischemia in the thoracic surgery for lung cancer.

[Results and problems of thymectomy in myasthenia gravis over 65 years old].

From June 1975 to March 1999, 300 cases of myasthenia gravis (MG) have undergone thymectomy. Twenty-eight patients over 65 years old were examined, focusing on the relationship between clinical appearances and microscopic findings of the thymuses. Among these cases, six were classified as ocular type (one case with thymoma) and 22 generalized type (eight cases with thymoma). According to the thymoma registering stages defined by Masaoka and colleagues, those nine cases with thymoma associated with stages I (n = 7), II (n = 1) and III (n = 1), respectively. The case of stage III (74 year old female) died four years and eight months after surgery. The case of stage II died of old age two years after the surgery. Complete remission was achieved in two cases of stage I. The follicular hyperplasia were seen in eight cases, and all resulted in improvement. Nine cases with no particular findings of thymuses classified into four ocular type and five generalized type including one fulminating type. Post-operative course of all these cases were uneventful. Although one recurrent of the thymoma and one death of the tumor were observed, post-operative outcomes of these elderly patients were generally satisfactory. We concluded that there is an operative indication of thymectomy for MG of even elderly patients, if no particular findings were recognized in the thymus.

Replacement of the ascending aorta and aortic valve with a composite graft: operative and long-term results.

The purpose of this study is to analyze our treatment experience on patients with ascending aortic aneurysms, with aortic regurgitation. From January 1974 to December 1995, 49 patients underwent replacement of the aortic valve and ascending aorta with a composite graft, in which primary operation cases were 44 and reoperation ones were 5. The Bentall technique was used in 20 patients, the button technique in 11, the interposition graft technique in 11, and a combination of the interposition graft and button technique in 7. All but one reoperation cases underwent the interposition graft technique. Hospital mortality was 30% for the Bentall technique, and 9.1% for the button technique and 9.1% for the interposition graft technique; there was no hospital mortality in the combination of the interposition graft and button technique. Hospital mortality of interposition graft technique in primary operation cases was 9.1%, and that in reoperation cases was 0%. Hospital mortality in patients underwent from 1974 to 1985 was 30.8%, 27.8% from 1986 to 1991, and 0% from 1992 to 1995. Five late deaths occurred in the Bentall group (35.7%) and one late death in the button technique (9.1%). Not late deaths in the other groups have occurred. In summary, operative mortality in Bentall technique group was higher than that of the other groups. Operative results were improved by the change of operative methods. The interposition graft technique is preferable for patients undergoing reoperation or when tension on the ostial anastomoses may occur. The button technique is best for patients with aortic dissection or inflammation involving the coronary ostia.

[Successful cardiac surgery using normothermic cardiopulmonary bypass in an elderly patient with cryoglobulinemia].

The case of 70-year-old woman with cryoglobulinemia who underwent urgent operation for angina pectoris and mitral regurgitation is reported. Three bypass grafts and mitral valvuloplasty were performed under normothermic cardiopulmonary bypass with continuous warm blood cardioplegia. The postoperative course was uneventful. Normothermic cardioplegia requires further study as a technique for managing patients with cold autoimmune diseases such as cryoglobulinemia who require cardiopulmonary bypass.

[Replacement of the prosthetic aortic valve within a composite graft].

In 1974, a 36-year-old man underwent composite graft replacement of the aortic valve and the ascending aorta with a Starr-Edwards prosthesis (2320). In 1993, he had hemolytic anemia due to cloth wear of the Starr-Edwards prosthesis. The prosthetic aortic valve was removed and replaced without replacement of the conduit. This technique was simple and safe, and was useful to avoid unnecessary dissection.

Acute hemodynamic changes after Fontan operation: an experimental study.

Seven adult mongrel dogs with an average body weight of 11.3 kg were subjected to experimental Fontan operation in order to evaluate acute hemodynamic changes at the Fontan circulation. The Fontan circulation was established by occlusion of the tricuspid valve with tightening a purse-string suture which was placed around the valve under inflow occlusion and was passed through the anterior right atrial wall, and by connection with a 10 mm Gore-Tex graft between right atrium and pulmonary artery. When the Fontan circulation was established, aortic pressure and cardiac output (CO) decreased from 94.9 +/- 22.0 mmHg to 41.9 +/- 6.0 mmHg and 0.907 +/- 0.179 liter/min to 0.259 +/- 0.072 liter/min, respectively. There were no significant changes in heart rate and systemic vascular resistance between normal and the Fontan circulations. On the other hand, pulmonary vascular resistance (PVR) increased from 11.6 +/- 7.3 units in the normal circulation to 21.8 +/- 13.0 units in the Fontan circulation. From this study it was concluded that main changes in hemodynamic parameters immediately after establishing the Fontan circulation were marked decrease in systemic arterial pressure and CO, and an increase in PVR. Therefore, one should consider a possibility of an increase in the PVR to the critical level when the Fontan operation was applied to patients with pulmonary hypertension.

[Experimental study on avoidance of surgical heart block in septation for single ventricle].

A new method was developed to prevent surgical injury of the atrioventricular conduction system in septation for single ventricle. The new method includes the use of small Teflon pledgets to cover the conduction system at the crossing sites of suture line, and so that stitches can be placed on the pledgets to skip the conduction system. This paper describes the results of an experimental study to delineate the effects of covering pledgets on the morphology and function of the underlying conduction tissues. Deep hypothermia was employed for this experiment in 15 mongrel dogs. The small Teflon pledgets were sutured to bridge the endocardial surface of the atrioventricular node through the right atriotomy. They were subjected to sacrifice at 1 week to 12 months postoperatively. Electrophysiological study including electrocardiography. His bundle electrography and responsiveness of the atrioventricular conduction to rapid stimulation was done before the sacrifice. The resected heart was embedded in Ceroidin-Paraffin and serially sectioned for pathological study. No noticeable injuries were noted in the underlying conduction system. The electrophysiological study showed normal sinus rhythm at the time of sacrifice. No significant changes were noted in PQ intervals comparing to preoperative state. There were no significant differences in AH intervals, HV intervals and responsiveness to rapid atrial stimulation between experimental and normal control groups. In conclusion, the Teflon felt pledgets were demonstrated to have no detrimental effects on the atrioventricular conduction system in the chronic stage.

[Expanded indication of percutaneous transluminal coronary angioplasty to the infarcted zone--using thallium-201 exercise scintigram after rehabilitation].

In some cases of old myocardial infarction (OMI), left ventricular wall motion was improved after revascularization, though viability of the infarcted myocardium was not detected by left ventriculography (LVG) and exercise thallium-201 myocardial scintigraphy (EX-Tl). So to obtain more correct information of the viability, EX-Tl was performed again after ergometer rehabilitation for an OMI patient whose myocardial viability of the infarcted zone could not detected by LVG and EX-Tl. Incomplete fill in was showed in the EX-Tl after rehabilitation. So percutaneous transluminal coronary angioplasty (PTCA) was performed. Left ventricular wall motion was improved after three months. EX-Tl after rehabilitation is useful to evaluate the viability that could not detected by LVG and EX-Tl.

Blood levels and distribution of talampicillin and bacampicillin in NZW rabbits.

Parameters for blood concentrations of the peroral antibiotics talampicil in and bacampicillin, in NZW rabbits were determined using a two compartment model. On the basis of these pharmacokinetic parameters, a three compartment model was prepared for the concentrations of these drugs in the tongue, gingiva, submandibular gland, parotid gland, cervical lymph-node and mandibular bone. Simulation curves based on the parameters of tissue concentrations revealed visual conformity to the measured values.

[Fundamental and clinical studies of cefaclor in oral surgery].

Fundamental and clinical studies on cefaclor (CCL) have been performed and the following results were obtained. CCL was orally administered to NZW rabbits at the dose of 20 mg/kg, and its concentrations in blood and various tissues of oral organs were determined. Pattern of change in its blood concentration after the administration was similar to that of change in its concentration in the tissues of oral organs. Its concentration in blood was the highest followed by gingiva, parotid gland, submandibular gland, cervical lymph node and tongue in descending order. Comparative studies of CCL against cephalexin (CEX) were conducted in 5 healthy volunteers with cross over method. The 5 volunteers were orally given 500 mg of CCL or CEX at 1 dose after meal. Peak blood levels of CCL and CEX were 14.8 micrograms/ml at 2 hours and 11.5 micrograms/ml at 3 hours, respectively. The dose of 750 or 1,500 mg/day of CCL in 3 divided doses was orally administered to 71 patients with acute purulent infections in oral tissues for 3 to 13 days. Evaluation of effect was determined by the criteria for evaluation of antimicrobial agents in oral surgery. Out of the 70 patients, excellent clinical response was observed in 18 patients, good in 40, and poor in 12. Effective rate was 83%. In vitro antibacterial activities (MIC) of CCL and CEX were studied in 74 out of 81 strains (41 from aerobes and 40 from anaerobes) isolated from 47 patients. CCL showed stronger antibacterial activities than CEX. MICs of CCL against 30 strains of Gram-positive anaerobes were distributed from 0.10 to 3.13 micrograms/ml with a peak of 0.78 micrograms/ml. As adverse reaction due to CCL, eruption was observed in only 1 patient. Laboratory tests in 61 patients who received CCL showed elevation of GOT in 1 patient and elevation of GOT and GPT in 1 patient. From the above fundamental and clinical results, CCL was considered to be a useful antibiotic for the treatment of acute purulent infections caused by aerobes and anaerobes in oral surgery field.

[Study on distribution to oral tissues of long acting amoxicillin].

The distribution of L-AMPC, a newly developed long acting amoxicillin granules, was studied in oral tissues using New Zealand White rabbits. The antibiotic was dosed at 20 mg/kg and the tissue concentrations were measured in the tongue, gingiva, submaxillary gland, cervical lymph node and the parotid gland. Amoxicillin concentrations in liver and kidney were monitored for reference and urinary recovery was measured over 5 hours. All tissue concentrations were both high and persistent whereas amoxicillin concentrations in kidney and liver were high and low, respectively, the observation consistent with the published data for amoxicillin.