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Biomedical subjects

K Kono

Publications and source records attributed to K Kono.

At least 253 records · Page 14Linked to original sources
PubMed1981

Plasma vasopressin levels and urinary sodium excretion during cardiopulmonary bypass with and without pulsatile flow.

The use of pulsatile perfusion during bypass should create a more physiological milieu and thus attenuate the vasopressin stress response. To determine this, 20 patients scheduled for elective coronary artery bypass operation were studied in two groups. Group 1 had a standard nonpulsatile perfusion, and in Group 2 a pulsatile pump was used. Measurements were made before and after anesthesia, after surgical incision, and at 15 and 30 minutes during and after cardiopulmonary bypass. In both groups, vasopressin levels were significantly elevated after sternotomy (4.5 +/- 1.5 to 37 +/- 10 pg/ml in Group 1 and 3.1 +/- 1.2 to 33 +/- 9 pg/ml in Group 2, p less than 0.05) and during bypass (198 +/- 19 pg/ml in Group 1 and 113 +/- 16 pg/ml in Group 2) but were higher in Group 1 (p less than 0.05). With comparable perfusion pressures in both groups, Group 2 required higher flow (4.2 +/- 0.2 versus 3.5 +/- 0.3 L/min, p less than 0.05) and had lower resistance (1,351 +/- 182 versus 1,841 +/- 229 dynes sec cm-5, p less than 0.05) and higher urine Na+ (123 +/- 5 versus 101 +/- 8 mEq/L, p less than 0.05). These data demonstrate that pulsatile flow can significantly attentuate the vasopressin stress response to bypass. Since vasopressin, at these concentrations, is a potent vasoconstrictor and is capable of producing a Na+ diuresis, this may partially explain the higher flow requirements and the decrease in Na+ excretion.

Blood Pressure↗
PubMed1981

The use of H1 and H2 histamine antagonists with morphine anesthesia: a double-blind study.

High doses of morphine can produce significant cardiovascular effects generally attributed to histamine release. The authors examined the possibility that H1 and H2 histamine antagonists might prove beneficial in preventing these responses. In a randomized double-blind study, four groups of 10 patients each received 1 mg/kg morphine and either a placebo, diphenhydramine (H1), cimetidine (H2), or both of the histamine antagonists. The morphine-placebo group demonstrated a marked elevation in plasma histamine levels (880 +/- 163 to 7437 +/- 2684 pg/ml), a decrease in systemic vascular resistance (SVR) (15.5 to 9.0 l torr/(l . min-1) and diastolic BP (71 +/- 3 to 45 +/- 4 torr) and an increase in cardiac index (CI) (2.4 +/- 0.2 to 3.0 +/- 0.21 . min-1 . m-2). The administration of either cimetidine or diphenhydramine with morphine provided minimal protection. Those patients who received morphine and both antagonists demonstrated significant attenuation of these responses (CI 2.5 +/- 0.2 to 2.5 +/- 0.1 l . min-1 . m-2; SVR 17.4 to 14.6 torr/(l . min-1) although plasma histamine levels showed a comparable increase (1059 +/- 222 to 7653 +/- 4242 pg/ml). These data demonstrate directly that many of the hemodynamic effects of morphine can be attributed to histamine release. They further demonstrate that significant hemodynamic protection can be obtained by the use of histamine antagonists and the combination of H1 and H2 antagonists is superior to either given alone.

Blood Pressure↗
PubMed1981

Pili mediated agglutination of Serratia marcescens in human urine.

Of 51 strains of Serratia marcescens isolated from patients with urinary or respiratory tract infections, 35 agglutinated in human urine. The agglutinating strains possessed numerous pili which were morphologically distinct from common pili or type I pili. The diameter of the pili was 3 nm and the average length was 0.3 micrometer. Electron microscopic examination showed that 80% or more of the cells of the agglutinating strains and 0 to 8% of the cells of the nonagglutinating strains were piliated. When an agglutinating strain was heated at 55 C for 10 min, it lost its agglutinating capacity and concomitantly its pili. These results suggest that the agglutination might occur because of interactions between the pili and some factors in human urine. The urinary slime appears to contain these agglutinating factors.

Agglutination↗
PubMed1981

Attenuation of the stress response to cardiopulmonary bypass by the addition of pulsatile flow.

The effect of pulsatile flow during cardiopulmonary bypass on the hormonal stress response was studied in 26 patients. Thirteen had routine and 13 had pulsatile bypass with an average pulse pressure of 30 mm Hg. Plasma vasopressin levels were significantly elevated during bypass in both groups, but were lower with pulsation (66 +/- 11 vs 36.3 pg/ml, p less than 0.05). Epinephrine levels increased in both groups during bypass, but were higher after bypass (1179 +/- 448 vs 713 +/- 140 pg/ml, p less than 0.05) and in the recovery room (1428 +/- 428 vs 699 +/- 155 pg/ml, p less than 0.05) in the nonpulsatile group. The same response was noted in the norepinephrine levels (924 +/- 225 vs 465 +/- 90 pg/ml, p less than 0.05; 1015 +/- 491 vs 717 +/- 112 pg/ml, p less than 0.05). There were no significant changes in renin activity in either group, but the increase after cardiopulmonary bypass was greater in the nonpulsatile group (2.0 +/- 0.7 vs 1.36 +/- 0.4 ng/ml/hr, NS). These data suggest that pulsatile flow significantly attenuates the vasopressin and catecholamine stress response to cardiopulmonary bypass. This may explain the increased flow requirements and better tissue perfusion and organ function and the decreased incidence of postoperative hypertension after bypass using pulsatile flow.

Blood Gas Analysis↗
PubMed1981

Renal function and stress response during halothane or fentanyl anesthesia.

The effects of anesthesia on hormonal stress response and renal function were measured before institution of cardiopulmonary bypass in two groups of patients undergoing elective coronary artery surgery. Group 1 (10 patients) received fentanyl, 100 microgram/kg, and N2O/O2; group 2 (12 patients) received halothane and N2O/O2. Patients in group 1 showed no significant changes in plasma levels of vasopressin, renin, or aldosterone during anesthesia or operation. This same group, however, demonstrated significant decreases in plasma levels of cortisol (8.4 +/- 1 to 4.2 +/- 1 microgram%, p less than 0.01), epinephrine (260 +/- 72 to 97 +/- 28 pg/ml, p less than 0.05), and norepinephrine (715 +/- 177 to 322 +/- 46 pg/ml, p less than 0.05) during operation. This was accompanied by an increase in urine volume (2.1 +/- 0.8 to 7.6 +/- 2 ml/min, p less than 0.05), a decrease in urine osmolality (610 +/- 82 to 166 +/- 60 mOsm/kg, p less than 0.01), and urine Na+ (54 +/- 12 to 16 +/- 4 meq/L, p less than 0.01) and no change in creatinine clearance. In contrast, in the group 2 patients during operation plasma levels of cortisol (11.7 +/- 2 to 31.1 +/- 2 microgram%, p less than 0.01), aldosterone (60 +/- 14 to 106 +/- 2 pg/ml, p less than 0.01), and vasopressin (10.4 +/- 1 to 23.3 +/- 3 pg/ml, p less than 0.01) all increased. This was accompanied by a significant decrease in creatinine clearance (148 +/- 52 to 92 +/- 12 ml/min/m2, p less than 0.05). The data demonstrate that high dose fentanyl anesthesia can significantly attenuate the hormonal stress response to operation and preserve renal function. They also suggest that decreases in renal function observed with anesthesia and operation may be a reflection of the hormonal changes associated with surgical stimulation.

Aldosterone↗
PubMed1978

Cancer chemotherapy model using autochthonous large bowel cancer in rats.

Chemotherapy of methylnitrosourea-induced autochthonous large bowel cancer in rats, which is similar to that in man, was studied to evaluate the intrarectal administration or topical application of chemotherapeutic agents. Rats with large bowel tumors confirmed by endoscopic examination received an intrarectal instillation of 1 mg of 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU), 1 mg of 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea (Me-CCNU), or 5 mg of 5-fluorouracil (ir groups), or intraperitoneal injection of 2.5 mg of 5-fluorouracil (ip group) daily for 8 weeks. All the rats, including non-treated control rats, were necropsied after the treatment. The number of large bowel tumors per rat detected by endoscopy before the treatment was mostly the same among groups, whereas that observed at necropsy after the treatment was significantly smaller in ir groups, compared to non-treated group and ip group. The tumors increased significantly in rats of non-treated group and ip group between the time of endoscopy and necropsy, but not in rats of ir groups. These results showed that the maximum tolerated dosage of the agents administered intrarectally suppressed the development of new tumors after start of the treatment and also the growth of tumors which were detected by endoscopy before the treatment.

Administration, Topical↗