PubMed Health⌕ Search

Biomedical subjects

I Takenaka

Publications and source records attributed to I Takenaka.

At least 19 recordsLinked to original sources
PubMed2000

A new method of predicting pulmonary capillary wedge pressure: the arterial pressure ratio.

The response of arterial blood pressure to an increase in intrathoracic pressure has been shown to be predictive of pulmonary capillary wedge pressure. We devised a new method, which we termed the arterial pressure ratio. We defined arterial pressure ratio as the ratio of systolic blood pressure of the final beat during the strain phase of the Valsalva manoeuvre to that during apnoea before the manoeuvre, and tested the accuracy of arterial pressure ratio in predicting pulmonary capillary wedge pressure. In 30 patients scheduled for elective abdominal aortic reconstruction, following induction of general anaesthesia and tracheal intubation, a 20-G catheter and pulmonary artery catheter were inserted through the radial artery and right internal jugular vein, respectively. Pulmonary capillary wedge pressure was then measured during a brief period of apnoea and the Valsalva manoeuvre was performed by application of pressure to the reservoir bag. Airway pressure was maintained at 30 cmH2O for 10 s and then released. Radial arterial pressure and airway pressure were recorded simultaneously, and arterial pressure ratio was calculated. There was a close linear correlation between arterial pressure ratio and pulmonary capillary wedge pressure (r = 0.88, p < 0.0001).

Aged↗
PubMed2000

Spermatogenic disturbance induced by di-(2-ethylhexyl) phthalate is significantly prevented by treatment with antioxidant vitamins in the rat.

Phthalate esters, now regarded as endocrine disruptors, are widely used in the plastics industry. In particular, di-(2-ethylhexyl) phthalate (DEHP) is produced in large quantities, and is used in blood storage bags, catheters and haemodialysis instruments. Previous studies have demonstrated that treatment of rats with DEHP induces testicular atrophy with liver enlargement, although the precise nature and mechanism of the action of DEHP on these organs remains unclear. In the present study, we produced an experimental model of DEHP-induced spermatogenic disturbance in rats by feeding them a DEHP-containing diet. Liver enlargement occurred in rats fed either a 1 or 2% DEHP-containing diet. However, testicular atrophy accompanied by aspermatogenesis was induced by feeding with the 2% but not with the 1% DEHP-containing diet. This suggests that the critical DEHP dose for gonadotoxicity is higher than that for hepatotoxicity. Using the 2% DEHP-dose, the effect of simultaneous administration of antioxidant vitamins (= vitamins C and E) was next examined. It was found that the vitamin supplementation significantly prevented the testicular injury. The results suggest that antioxidant vitamins can protect the testes from DEHP-toxicity.

Animals↗
PubMed2000

[A case of free rupture of abdominal aortic aneurysm into the peritoneal cavity during posture change after induction of anesthesia].

We report a case in which posture change for radiography after induction of anesthesia caused free rupture of the abdominal aortic aneurysm (AAA) into the peritoneal cavity, resulting in shock, although in the patient an AAA had ruptured into only the retroperitoneal space and hemodynamics had been stable preoperatively. The massive bleeding was controlled with autotransfusion using a washing salvaging autotransfusion device and a roller pump for hemodialysis. In addition, international mild hypothermia was effective for protection of the brain from suspected ischemia during shock. Meticulous attention should be paid for anesthetic management of patients with ruptured AAA even if their hemodynamic status is stable.

Aged↗
PubMed2000

[Anesthetic management of a patient with deep venous thrombosis using temporary inferior vena cava filter].

A patient with deep venous thrombosis caused by a huge uterine leiomyoma underwent abdominal hysterectomy. To prevent pulmonary thromboembolism, the patient received anticoagulant therapy until 6 hr before surgery and temporary inferior vena cava filter was placed. A combination of preoperative anticoagulant therapy and the filter placement during perioperative period enabled this patient to be successfully-managed.

Anesthesia, General↗
PubMed1999

Fibreoptic assessment of laryngeal aperture in patients with difficult laryngoscopy.

PURPOSE: To determine the relationship between the area of the laryngeal aperture (LA) seen fibreoptically during laryngoscopy and the difficulty of tracheal intubation in patients with difficult laryngoscopy METHODS: In 587 adult patients after induction of general anesthesia and muscle relaxation, the best laryngoscopic view of the larynx using a Macintosh 3 blade was classified according to Cormack. When the LA could not be seen, with laryngoscope blade in place, the LA view provided by a fibreoptic bronchoscope (FOB)-camera passed nasally was photographed. Then, the laryngoscopist attempted to intubate the trachea using the Macintosh blade. Tracheal intubation requiring more than three attempts was defined as difficult. After the third attempt, the trachea was intubated orally aided by FOB. The LA view after jaw thrust during FOB-aided intubation was photographed. RESULTS: Laryngoscopy was difficult in 17 of 587 patients. In four, intubation was difficult. In the remaining 13 patients the trachea was easy to intubate. The LA area obtained by the FOB in the difficult group (median, 0.19; intra-quartile range, 0.14 to 0.39 cm2) was smaller than that in the easy group (2.43; 1.84 to 2.93 cm2)(P = 0.003). In contrast, the LA area provided by jaw thrust during the FOB-aided intubation in the difficult group (2.28; 1.99 to 2.73 cm2) was similar to that during laryngoscopy in the easy group. CONCLUSION: Inability of the laryngoscope to provide an adequate LA view is one cause of difficult intubation with the Macintosh laryngoscope in patients with difficult laryngoscopy.

Adult↗
PubMed1999

Development of rapid atrial fibrillation with a wide QRS complex after neostigmine in a patient with intermittent Wolff-Parkinson-White syndrome.

We report the case of a 67-yr-old man with intermittent Wolff-Parkinson-White (WPW) syndrome in whom neostigmine produced life-threatening tachyarrhythmias. The patient was scheduled for microsurgery for a laryngeal tumour. When he arrived in the operating room, the electrocardiogram showed normal sinus rhythm with a rate of 82 beat min-1 and a narrow QRS complex which remained normal throughout the operative period. On emergence from anaesthesia, the sinus rhythm (87 beat min-1) changed to atrial fibrillation with a rate of 80-120 beat min-1 and a normal QRS complex. We did not treat the atrial fibrillation because the patient was haemodynamically stable. Neostigmine 1 mg without atropine was then administered to antagonize residual neuromuscular block produced by vecuronium. Two minutes later, the narrow QRS complexes changed to a wide QRS complex tachycardia with a rate of 110-180 beat min-1, which was diagnosed as rapid atrial fibrillation. As the patient was hypotensive, two synchronized DC cardioversions of 100 J and 200 J were given, which restored sinus rhythm. No electrophysiological studies of anticholinesterase drugs have been performed in patients with WPW syndrome. We discuss the use of these drugs in this condition.

Aged↗
PubMed1999

Malposition of the epiglottis after tracheal intubation via the intubating laryngeal mask.

The intubating laryngeal mask has been reported to be a successful method of tracheal intubation although advancement of the tracheal tube via the laryngeal inlet into the trachea cannot be seen. Damage to the larynx or other tissues may occur during blind passage of a tracheal tube. We report a case in which the tracheal tube, advanced blindly, tucked the epiglottis into the laryngeal inlet, resulting in oedema of the epiglottis. This case illustrates the potential for airway obstruction after extubation when using the intubating laryngeal mask as a blind intubation guide.

Epiglottis↗
PubMed1999

[Clinical statistics of stage I testicular tumor].

PURPOSE: A survey of stage I testicular tumors in the Chugoku-Shikoku district was taken in order to explore the clinical characteristics. PATIENTS AND METHODS: Three hundred and forty eight cases of stage I testicular tumor treated at 46 facilities in the Chugoku-Shikoku district between 1984 and 1992 were collected. Subjects' background factors, treatment methods and prognosis were studied. RESULTS: Tissue types were 249 (71.6%) seminoma and 99 (28.4%) non-seminoma. Adjuvant therapy for seminoma cases included 138 post-operative radiotherapy (4 recurrences, 3 cancer deaths), 57 chemotherapy (no recurrences, 2 contralateral testis tumor cases) and 48 were under surveillance (no recurrence). Adjuvant therapy for non-seminoma cases included 47 chemotherapy (1 recurrence) and retroperitoneal lymph node dissection was performed on 6 cases. Forty cases were under surveillance (1 recurrence). Of 8 (2.3%) cases with recurrence, 6 showed onset within two years and 2 after two years. Four of the 8 cases with recurrence were seminoma (1.1% of seminoma cases) and the other 4 were non-seminoma (4.0% of non-seminoma cases). All 3 (0.9% of all cases) of the cancer death cases were seminoma that received post-operative radiotherapy, while there were no cancer deaths in non-seminoma cases. CONCLUSION: Prognosis of stage I testicular tumor is good. Although the recurrence rate was higher in non-seminoma cases, cancer deaths were only observed in seminoma cases.

Adolescent↗
PubMed1999

[Anesthetic management of a patient with Bartter's syndrome].

A 48-year-old woman with Bartter's syndrome underwent right mastectomy under general anesthesia. Her operative course was uneventful. She was preoperatively complicated with severe hypokalemia but had no signs and symptoms of hypokalemia. In anesthetic care of patients with Bartter's syndrome, even when they have no symptoms of hypokalemia, the meticulous intravenous administration of potassium chloride is required in order to maintain the preoperative level of the serum potassium during anesthesia. In addition, attention should be paid to factors causing an additional reduction in the serum potassium concentration, such as alkalosis, elevated beta 2-adrenergic activity, increased availability of insulin and hypothermia.

Anesthesia, General↗
PubMed1999

[Light-guided tracheal intubation using a Trachlight: causes of difficulty and skill acquisition].

We studied the reasons why tracheal intubation using a lighted stylet (Trachlight) was sometimes difficult for unexperienced intubators. We also examined light-guided intubation skill acquisition in inexperienced anesthesiologists. Two anesthesiologists, with no prior experience in using a Trachlight, performed orotracheal intubation using a Trachlight in 60 anesthetized patients (30 patients each). During intubation, an assistant observed the advancement of the tracheal tube using a fiberscope passed nasally and recorded the reason for difficulty in intubation. The time to successful intubation was also measured. Data were divided into epochs of 10 cases, and the intubation time and the incidence of difficult cases were compared between the groups. Tracheal intubation was successful using the Trachlight in 59 of 60 patients. The incidence of difficult cases, defined as cases requiring two or more attempts, was 31.7%. Fiberscopy showed that when the tube tip was located in the vallecula or in the esophagus, it was sometimes difficult to determine the position of the tube tip by transillumination of the soft tissues of the neck, and this results in the need for multiple attempts. Both the intubation time and the incidence of difficult cases decreased significantly between the first and last epoch. The present study confirms that light-guided intubation is sometimes difficult when the tube tip is advanced to the vallecula or to the esophagus. An acceptable level of skill in light-guided intubation is achieved within 30 uses.

Adult↗