PubMed Health⌕ Search

Biomedical subjects

A Tajiri

Publications and source records attributed to A Tajiri.

At least 19 recordsLinked to original sources
PubMed2000

Colonoscopic polypectomy with cutting current: is it safe?

BACKGROUND: Coagulation and blended electrosurgical current are currently recommended for colonoscopic polypectomy, whereas pure cut current is believed to be associated with a higher risk of bleeding. However, the outcome of polypectomy performed with a cut current has not been evaluated in a large case series. Our objective was to study the incidence and nature of complications when polypectomy is performed with a pure cut current. METHODS: Among 9555 colonoscopic examinations, polypectomy cases were retrospectively reviewed for complications. The electrosurgical current applied was always the cutting waveform. RESULTS: Electrosurgical polypectomy using pure cut current was performed to remove 4735 lesions. Hemoclips were applied to the excision site after polypectomy to prevent bleeding in 12% of the cases. Hemorrhage occurred in 1.1% of the polypectomies (3.1% of patients). The incidence of bleeding with the different methods was snare polypectomy 0.9%, endoscopic mucosal resection 1.6%, "hot" biopsy 0.4%, and piecemeal polypectomy 7.3%. Bleeding was immediate in 66.1% of episodes and delayed in 33.9%. Patients with delayed postpolypectomy bleeding were significantly younger than those with immediate bleeding (50.5 and 64.7 years, respectively, p < 0.001). There was 1 case of transmural burn, but no perforations. CONCLUSION: Polypectomy can be performed with pure cut current with a bleeding rate comparable to that seen with the use of coagulation or blended current, provided that hemoclip placement can be used readily. Expertise in hemoclip placement is advisable if this method of polypectomy is to be used.

Adult↗
PubMed1996

[Severe laryngeal edema immediately after extubation in a 93 year old female].

A 93-year-old female, who had post-operative respiratory insufficiency, was treated with artificial ventilation for 8 days. Immediately after extubation, dyspnea, cyanosis and unconsciousness occurred. Severe laryngeal edema was found by bronchofiberscopy and reintubation seemed impossible. She underwent emergency tracheotomy and barely survived the critical state. It should be kept in mind that severe laryngeal edema might develop immediately after long term intubation in supergeriatric patients associated with hyponutrition.

Aged↗
PubMed1994

[Effects on hemolysis of the manually operated portable cardiopulmonary bypass system].

We studied the effects on hemolysis of our manually operated, portable cardiopulmonary bypass system with two self-inflatable reservoir-pumps in parallel by using bovine blood. The blood shed from both the jugular vein and the carotid artery, immediately after slaughter, was divided into three plastic containers, one for the control, one for manual circulation, and the other for conventional circulation with a roller-pump. Small bore catheters were intentionally placed into the inflow and outflow routes of both circulation systems to simulate clinical situations. Free hemoglobin and potassium in plasma were measured every 30 min during the experimental circulation for 120 min. The free hemoglobin in plasma increased gradually under manual circulation, but this increase was statistically insignificant when compared with the variances of those in the conventional circulation and the control blood groups. The values of the potassium in the plasma showed no differences among the three blood groups. Our manually operated, portable cardiopulmonary bypass system will be a valuable adjunct for emergency medicine.

Animals↗
PubMed1993

[A manually operated cardiopulmonary bypass circuit with two self-inflating reservoir-pumps].

We improved our manually operated cardiopulmonary bypass circuit by adding another reservoir-pump in parallel to continue the venous blood withdrawal. The two reservoir-pumps were alternately and maximally compressed by hand, and hydrodynamics of the device was examined in vitro by using a physiological saline solution. When a 21 Fr, 52 cm catheter for venous drainage and a 17 Fr, 17 cm catheter for arterial infusion were used, the bypass flow rate was about 2.1 l.min-1 even under no waterhead. It was further increased to about 3.1 l.min-1 by adding a head of 60 cmH2O. The upper body of a patient undergoing resuscitation is occupied by other personnel performing mandatory procedures such as cardiac massage and endotracheal intubation. Therefore, the catheter insertion site is limited to the femoral vessels, and a long arterial return catheter will be necessary for a better cerebral oxygen supply. When a 17 Fr long arterial return catheter with 52 cm in length was used, the maximal flow rate achieved about 2.8 l.min-1 under a head of 60 cmH2O, though slightly smaller than that with the 17 cm catheter. This double reservoir-pump circuit with a long arterial return catheter will facilitate emergency cardiopulmonary bypass during acute critical resuscitation and much improve the perfusion to the vital organs.

Cardiopulmonary Bypass↗
PubMed1993

[A manually operated portable cardiopulmonary bypass circuit for emergency and its hydrokinetics].

We developed a manually operated portable cardiopulmonary bypass circuit for emergency. The priming volume of the circuit is about 300 ml, including the self-inflating reservoir-pump of 120 ml in capacity. The self-inflating reservoir-pump with two one-way valves can drain venous blood via the femoral vein without a water head, and return the blood into the femoral artery through a membrane lung. Bypass flow under various conditions was measured with an electromagnetic flowmeter. Pressure resistance of the artificial lung was also measured. When a DLP 21 Fr size catheter was used as a venous drainage catheter and DLP 17 Fr size for arterial infusion, bypass flow was 0.8-1.2l.min-1 without a water head for venous drainage, or 1.4-1.7l.min-1 with a 60 cm water head, respectively. One investigator could repeat squeezing the reservoir-pump for two hours under each condition. The bypass flow rates of the circuit depend upon the height of the water head and the internal diameters of the venous drainage catheter. The diameter of the arterial catheter affects the squeezing pressure, but it is overcome by manual force and has no influence on the flow rate. The lung had no significant resistance either to blood flow or insufflation gases.

Cardiopulmonary Bypass↗
PubMed1992

Gas-exchange function of a preprimed pediatric oxygenator stored for one year for emergency cardiopulmonary bypass.

To save priming time and perform more rapid initiation of emergency cardiopulmonary bypass for acute cardiopulmonary failure, an extracorporeal circuit with a hollow-fiber oxygenator (EL-2000 for pediatric use; Kurary Co. Ltd., Osaka, Japan) was preprimed, and the gas-exchange function was evaluated after 1 year of storage. EL-2000 has a dense polyolefin membrane with a surface area of 0.3 m2. When the bypass flow rates were 250, 500, 1,000, and 1,500 ml/min with 100% oxygen at the same flow rate as the bypass blood flow (namely, V/Q = 1) to the oxygenator, oxygen transport rates of the stored oxygenator were 19.6 +/- 0.3, 38.3 +/- 0.41, 64.4 +/- 0.9, and 76.4 +/- 2.7 ml/min (n = 5, mean +/- SD), respectively. PCO2 differences between pre- and postoxygenator blood (delta PCO2) were 18.6 +/- 1.4, 12.0 +/- 1.6, and 4.4 +/- 1.2 mm Hg at V/Q = 1 and the same bypass blood flow rates, respectively, excluding 1,500 ml/min, the data for which were excluded because of preparatory failure. PCO2 removal indices (defined as the ratio of delta PCO2 to PCO2 in preoxygenator blood) were 0.45 +/- 0.03, 0.29 +/- 0.12, and 0.10 +/- 0.03, respectively. Though the evaluation was done using only a single oxygenator, we feel strongly that the gas-exchange function of the preprimed dense-membrane hollow fiber oxygenator will be preserved even after 1 year of storage.

Cardiopulmonary Bypass↗
PubMed1992

[A patient with severe ventricular tachycardia who was saved by prolonged extracorporeal lung and heart assist].

A 47-y-o man had been suffering from cardiac failure due to refractory ventricular tachycardia (VT) after myocardial infarction. He underwent resection of the left ventricular aneurysm and cryocoagulation of the arrhythmogenic foci. On the 2nd post-operative day, VT often recurred in spite of repeated cardioversion and drug therapy, and threatened his life, even under IABP. Therefore, a veno-arterial bypass route was made and extracorporeal lung and heart assist, ECLHA, was started with a heparin bonded Maxima lung on the following day. Even under ECLHA, VT continued to recur. Cryocoagulation of the VT foci was tried again, without immediate success. A record high dose of beta-blockers, given under the circulatory support by ECLHA, stopped VT on the following day. The patient was weaned from the ECLHA circuit 12 days after the first operation, then from IABP on the 14th day. During the 10 day course of surgeries and ECLHA, the patient had almost 100 defibrillations. But for ECLHA, we may say that the patient couldn't have survived two open heart surgeries, administration of a great amount of beta-blockers, and repeated cardiac arrest without neurological sequelae.

Adult↗
PubMed1992

[A volume-variable reservoir-pump for a manually operated cardiopulmonary bypass circuit for emergency].

We developed a manually operated portable cardiopulmonary bypass circuit for resuscitation. The circuit is composed of, in turn, a venous drainage catheter, one-way valve, self-inflating reservoir, one-way valve, artificial lung, and an arterial catheter. These components are interlocked with conducting tubes with quick connectors. The priming volume of the circuit is about 300 ml including the self-inflating reservoir of 120 ml in capacity. For a patient with small stature, stroke volume is easily controlled by changing manual compression of the reservoir, but dilution of circulating blood with the priming solution is inevitable. For a controllable reduction of the reservoir volume, we incorporated a thin-walled balloon, which is inflatable from the outside, into the room of the reservoir. If the balloon is inflated with some amount of liquid, the same volume of functional capacity of the reservoir is lost. Thus the reservoir volume is adjusted, the hemodilution with a priming solution is minimized, and an excessive stroke volume with an inadvertent compression of the reservoir-pump is prevented as well. This innovation will make our standard size bypass circuit applicable to almost all patients, except for a newborn or infant who requires a special size of bypass circuit, and improve the survival rate of cardiopulmonary resuscitation.

Cardiopulmonary Bypass↗
PubMed1990

Isolation of multiple cytomegalovirus strains from a patient with adult T cell leukemia.

A 66-year-old male with adult T cell leukemia had an ulcer on the left medial thigh. The biopsy of the skin lesion revealed enlarged endothelial cells with acidophilic intranuclear inclusion bodies, suggesting cytomegalovirus (CMV) infection. At autopsy, CMV was isolated from a nodular skin lesion of the scrotum. The urine constantly tested positive for CMV. Restriction endonuclease cleavage analysis of DNA of the isolates from the skin and urine indicated that this patient was infected with two different strains of CMV.

Aged↗
PubMed1989

Separation of human neutrophils in self-generated continuous density gradients of Percoll.

Human neutrophils were separated into two fractions using a continuous density gradient of Percoll solution. A marked decrease in O2- production was observed in the low-density neutrophil fraction. There was little erythrocyte contamination in the high-density neutrophil fraction (less than 0.5%), and thus the hypotonic or ammonium chloride lysis of erythrocytes was not necessary.

Cell Separation↗
PubMed1989

[T-cell lymphomas of the skin: a study of 7 cases excluding mycosis fungoides and adult T-cell leukemia/lymphoma].

Seven cases of T-cell lymphomas of the skin, excluding mycosis fungoides and adult T-cell leukemia/lymphoma, treated at the Department of Dermatology, Miyazaki Medical College for the previous 5 years were studied. Five were males and 2 were females, with a mean age of 61 years. Six patients presented either multiple skin tumors or subcutaneous indurations. Histologically, all cases presented dense infiltrations of the tumor cells showing variable morphological characteristics. Surface markers were also variable, suggesting that these were not a single entity. Treatment consisted of chemotherapy in 5 cases and electron beam therapy in 5 (localized in 4 and generalized in 1). Complete remission was obtained in 5 cases. The mean period from the first examination to death in the three fatal cases was 11.7 months, and the mean period of observation from the first examination to the present time in 4 cases ranged from 12 months to 40 months. Clinicopathological characteristics of these cases were compared with those of adult T-cell leukemia/lymphoma.

Adult↗