Biomedical subjects

O Yuge

Publications and source records attributed to O Yuge.

At least 19 recordsLinked to original sources

PubMed2001

Small dose of prostaglandin E(1) increases cardiac output without altering blood volume.

STUDY OBJECTIVE: To investigate the effect of small dose of intravenous (IV) prostaglandin E(1) (PGE(1)) on blood volume (BV) and cardiac output (CO) by pulse dye-densitometry (PDD) in patients administered isoflurane anesthesia. DESIGN: Prospective, randomized study. SETTING: University hospital. PATIENTS: 14 ASA physical status I and II adult patients undergoing elective neurosurgery. INTERVENTIONS: Patients were randomly assigned to either the PGE(1) group (n = 7) or the control group (n = 7). Anesthesia was induced with thiamylal, fentanyl, and vecuronium, and maintained with isoflurane and nitrous oxide. When the cardiovascular system stabilized after craniotomy and incision of the dura mater, we administered a small dose of PGE(1) at a rate of 0.02 microg/kg/min (PGE(1) group) or saline at a rate of 2 mL/min (control group). MEASUREMENTS AND MAIN RESULTS: Blood volume, CO, and mean transit time (MTT) were measured by PDD before and 60 minutes after the start of administration. At the same timing, mean arterial pressure (MAP), heart rate (HR), and central venous pressure (CVP) were measured, and systemic vascular resistance (SVR), cardiac index (CI), and CO/BV were computed. As for MAP, there was no significant difference within a group and between groups. In the PGE(1) group, significant increases were noted in CI from 2.54 +/- 0.46 to 3.24 +/- 0.83 (mean +/- SD) L/min/m(2) (p < 0.05), in CO/BV from 0.90 +/- 0.24 to 1.19 +/- 0.33 (p < 0.05), and in HR from 65.7 +/- 10.1 to 74.9 +/- 12.1 bpm (p < 0.05), and a significant decrease was observed in MTT from 22.3 +/- 6.5 to 18.2 +/- 5.1 seconds (p < 0.05 ). Cardiac index and CO/BV in the PGE(1) group increased higher than in the control group, while BV, CVP and SVR remained consistent in both groups. CONCLUSIONS: A small dose of PGE(1), low enough not to provoke hypotension, increased CO without alterations in BV. The increase in CO seemed to be mainly due to an increase in HR.

Alprostadil↗

PubMed2001

Glucose loading during primary culture has opposite effects on the viability of hepatocytes exposed to potassium cyanide and to iodoacetic acid.

Whether or not to apply nutritional pretreatment and how to do so are controversial issues with respect to the liver about to undergo aggressive intervention. We studied the effects of glucose loading on the viability of hepatocytes that were subsequently exposed to the inhibitors of carbohydrate metabolism, potassium cyanide (KCN) and iodoacetic acid (IAA). After rat hepatocytes were cultured for 24 hours in Leibovitz's L-15 medium containing 0, 10, 20, and 30 mmol/L glucose, the medium was replaced with modified Hanks-HEPES buffer with or without 2.5 mmol/L KCN or 0.5 mmol/L IAA. Lactate dehydrogenase (LDH) activity, lactate concentration, and pH of the supernatant were measured after 0, 2, 4, and 6 hours of exposure to KCN and after 0, 20, 40, and 60 minutes of exposure to IAA. Glycogen and adenosine triphosphate (ATP) contents in the hepatocytes were measured simultaneously. Hepatocytes cultured with various concentrations of glucose for 24 hours stored levels of glycogen in proportion to the glucose concentration in the culture medium without any significant difference in viability. The hepatocytes cultured with higher glucose concentrations maintained a higher ATP content and released less LDH and more lactate, and the pH decreased in the supernatant during exposure to KCN. Conversely, hepatocytes cultured with lower glucose concentrations maintained a higher ATP content and released less LDH during exposure to IAA. In conclusion, prior glucose loading appears to be beneficial for hepatocytes if oxidative phosphorylation is to be inhibited, whereas withholding glucose appears to be beneficial if glycolysis is to be inhibited.

Adenosine Triphosphate↗

PubMed2001

A prospective multicenter trial to determine the incidence of transient neurologic symptoms after spinal anesthesia with phenylephrine added to 0.5% tetracaine.

The addition of vasoconstrictors for spinal anesthesia is controversial, since an increase in the incidence of transient neurologic symptoms (TNS) has been reported. A multicenter, randomized, double-blind study was conducted to assess the effectiveness of spinal anesthesia with phenylephrine in addition to tetracaine as well as the incidence of neurological complications. We studied 64 patients with comparable demographic characteristics who were scheduled for elective surgery for a lower limb, or a gynecological or urological procedure. The patients were allocated randomly into 2 groups. Group P (n = 34) received 0.5% tetracaine in 10% glucose with 0.025% phenylephrine, while group C (n = 30) received 0.5% tetracaine in 10% glucose. Our results showed that only 2 patients (6.7%) in group C experienced TNS, and their symptoms disappeared within 72 hr after anesthesia, while none of the patients (0%) in group P complained of symptoms. The incidence of TNS was thus not significantly different between the two groups. Six hours after the sensory block, group P patients demonstrated sensory disturbance, with the median spinal dermatome corresponding to the L1 segment. Moreover, systolic blood pressure in group P was significantly higher than that in group C, 5 min, 15 min, and 20 min after injection. The incidence of TNS in the present study does not seem to be greater after surgery with spinal anesthesia using 0.5% hyperbaric tetracaine and 0.5 mg phenylephrine than without phenylephrine. Randomized, double-blind, cross-over trials with a larger sample size would be required in the future to obtain more reliable results.

Anesthesia, Spinal↗

PubMed2001

[Patient-controlled epidural analgesia with bupivacaine and fentanyl suppresses postoperative delirium following hepatectomy].

Postoperative delirium occurs frequently following major surgery, especially after hepatectomy. We hypothesized that better methods of postoperative pain control would decrease postoperative delirium. To clarify the magnitude of postoperative pain and incidence of postoperative delirium in hepatectomy patients, subjects received patient-controlled epidural analgesia (PCEA) using bupivacaine and fentanyl (Group P), or continuous epidural mepivacaine (Group E) following intraoperative epidural administration of morphine. The magnitude of postoperative pain was estimated by use of an analgesic adjuvant and delirium was classified as mild (insomnia, disturbance of sleepwake cycle), moderate (disorientation, hallucination), or severe (restlessness, confusion, agitation), based on the medical records. Analgesic adjuvant usage was less in Group P than in Group E, while the incidences of moderate and severe delirium were significantly less frequent in Group P than in Group E (35.7% versus 75.0%, and 14.3% versus 50.0% respectively). Moreover, less amount of antipsychotic drugs was given in Group P than in Group E. These results suggest that the better pain relief and patient satisfaction provided by PCEA contributed to a decrease in the incidence of delirium, because of continuous opioid administration and patient-control analgesia. We concluded that PCEA with bupivacaine and fentanyl can limit postoperative delirium following hepatectomy.

Aged↗

PubMed2001

Endoscopic thoracic sympathicotomy in Japan.

We sent our members questionnaire asking about their activities. From December 1992 to the end of 2000, endoscopic thoracic sympathicotomy (ETS) was utilized in 7,017 cases in 50 hospitals and institutes. Of which 6,776 (96.6%) were performed on hypersweating. There have been no deaths related to ETS either during the hospital stay or following discharge. Intraoperative bleeding was reported in 28 cases (0.3%) and an open chest procedure to stop bleeding was required in 6 cases (0.08%). Short term Horner's syndrome after the operation was found in a few cases, however, permanent symptoms were recognized in only 18 (0.28%). The most common postoperative complaint was compensatory sweating on the chest, back, or abdomen. Most of these patients countered this condition by using several methods of prevention or protection and continued on their daily life with little restriction. However, 83 cases (1.2%) experienced severe compensatory sweating and consulted their doctors repeatedly for more than one year. All operators who perform ETS recognized the excellent results for hand and facial sweating. Further, many doctors prefer this procedure as a first treatment for vascular disorders in upper extremities.

Humans↗

PubMed2001

Propofol relaxes extrapulmonary artery but not intrapulmonary artery through nitric oxide pathway.

The object of this study was to compare vasorelaxing responses to propofol by the intrapulmonary artery (IPA) and the extrapulmonary artery (EPA), and to identify the mechanisms of action. Rat pulmonary arterial rings were isolated and suspended in organ chambers where isometric tension development was measured under optimal resting tension. All pulmonary arterial rings were pre-contracted with phenylephrine. Propofol (Diprivan) and the vehicle (10% Intralipid) were administered cumulatively in the presence or absence of N(omega)-nitro-L-arginine methyl ester (L-NAME). Sodium nitroprusside (SNP), a nitric oxide donor, was administered cumulatively. Propofol relaxed both EPA and IPA in a dose dependent manner (p<0.05), while the vehicle alone showed no effect. The vasorelaxing responses to propofol were significantly higher in EPA than IPA at higher concentrations (10(-4) M and 10(-4.5) M) (p<0.05), and were decreased by L-NAME in EPA (p<0.05), though it had no effect in IPA. The concentration for SNP causing 50% relaxation was not significantly different between the two arteries. We concluded that the response of smooth muscle to nitric oxide was the same between EPA and IPA; however, the vasorelaxing mechanisms of propofol seemed to be different between them at higher doses, suggesting that a mechanism exists and operates through the nitric oxide pathway.

Animals↗

PubMed2001

[A comparison of finger and nose probes in pulse dye-densitometry measurements of cardiac output, blood volume and mean transit time].

We compared finger and nose probes in measurement of cardiac output (CO), blood volume (BV) and mean transit time (MTT) with pulse dye-densitometry. These probes were intraoperatively applied to 6 patients under general and continuous epidural anesthesia. Indocyanine green (ICG) 20 mg, was given via peripheral venous route, and CO, BV and MTT were measured with DDG-2001 (NihonKoden, Japan). Eighteen measurements were done successfully. There was no significant difference between F-CO (CO with a finger probe, 4.48 +/- 1.40 l.min-1, mean +/- SD) and N-CO (CO with a nose probe, 4.14 +/- 1.87 l.min-1). F-MTT (32.9 +/- 11.1 sec) was significantly longer than N-MTT (19.9 +/- 6.4 sec, P < 0.01). The limits of agreement of F-CO and N-CO (mean difference +/- 2 SD) were -3.6 and +4.2 l.min-1, respectively. There was a significant negative correlation between differences in MTT and F-CO/N-CO (R2 = 0.448, P < 0.01). There was no significant difference between F-BV (3.97 +/- 1.23 l) and N-BV (3.97 +/- 0.98 l). The limits of agreement of F-BV and N-BV were -1.3 and +1.3 l, respectively. In conclusion, the measured values in BV showed good agreement and reliability with both finger and nose probes, while CO was less reliable when differences in MTT increased.

Anesthesia, Epidural↗

PubMed2001

A formula based on body length for determining the size of an uncuffed endotracheal tube for pediatric cardiac anesthesia.

Three hundred and thirty-four pediatric patients less than 4 years old who underwent surgery for congenital heart disease were retrospectively studied to devise a practical formula for predicting the appropriate size for an uncuffed endotracheal tube for pediatric cardiac anesthesia. Furthermore, this formula was compared with that for non-cardiac anesthesia obtained from 409 patients without congenital heart disease. A simple regression equation between tube size and body length resulted in the simple predictive formula: "tube size = 0.04 x body length + 1.6" for pediatric cardiac anesthesia. This formula had the same slope and an approximately 0.3 mm larger intercept on the Y-axis compared with that for pediatric non-cardiac anesthesia. Therefore, a one-size larger endotracheal tube is more suitable for use in pediatric cardiac anesthesia than in pediatric non-cardiac anesthesia for the same body length.

Anesthesia↗

PubMed2000

Effects of pneumoperitoneum on cardiac autonomic nervous activity evaluated by heart rate variability analysis during sevoflurane, isoflurane, or propofol anesthesia.

BACKGROUND: The effects of pneumoperitoneum on the activity of the cardiac autonomic nervous system have not been completely understood. METHODS: In this study, 45 unpremedicated adult patients who underwent laparoscopic cholecystectomy were anesthetized with either 3.5% sevoflurane, 2% isoflurane, or 8 mg/kg/h propofol (15 patients in each group). The status of cardiac autonomic nervous activity was evaluated by heart rate variability analysis three times: once when the patient was awake, once after induction of general anesthesia, and once after insufflation for pneumoperitoneum. Intra-abdominal pressure was maintained automatically at 10 mm Hg by a carbon dioxide (CO(2)) insufflator. For each measurement, electrocardiogram was recorded for 256 s and played back offline to detect R-R intervals. Power spectral analysis of heart rate variability was applied, and the low-frequency (LF, 0.04-0.15 Hz) and high-frequency (HF, 0.15-0. 40 Hz) bands of the spectral density of the heart rate variability were obtained from a power spectra of R-R intervals using the fast-Fourier transform algorithm. The HF/LF ratio also was analyzed. RESULTS: Measurements of heart rate variability in the three groups showed similar change. Although the power of HF, which represents parasympathetic nervous activity, did not change, the power of LF, which represents both sympathetic and parasympathetic nervous activity, decreased during the anesthetized stage and increased during the insufflated stage. The HF/LF ratio, which represents the balance of parasympathetic and sympathetic activity, increased after induction of general anesthesia, and decreased after insufflation. CONCLUSIONS: Our results suggest that pneumoperitoneum increases sympathetic cardiac activity. The choice of general anesthetic did not seem to have a major influence on the change in the cardiac autonomic nervous system after induction of pneumoperitoneum for laparoscopic cholecystectomy.

Adult↗

PubMed2000

Differential action of spasmolytic vasodilators on platelet aggregation and endothelial cell-dependent anti-aggregation.

BACKGROUND: The perioperative use of spasmolytic vasodilators during reconstructive or vascular surgery is an important therapeutic procedure to prevent vascular spasm. Platelet aggregation at vascular endothelium injured by the surgical manipulation is thought to be associated with the persistency of spasm, although little is known about the effects of these drugs on platelet aggregation and on anti-aggregation provoked by endothelial cells. METHODS: (1) To test the direct effect of vasodilators against platelet aggregation, change in light transmission through platelet-rich plasma (PRP) stimulated with 4 microg/ml collagen was measured in the absence or presence of pentobarbital, papaverine, prostaglandin E1 (PGE1), trinitroglycerin, nitroprusside, nicardipine, and diltiazem. (2) Effects of these drugs on endothelial cell-dependent anti-aggregation were then evaluated. Incubation buffer of cultured porcine aortic endothelial (PAE) cells, which were preincubated with vasodilators for 10 min prior to a 1-min stimulation with 1 microM bradykinin, was transferred to collagen-stimulated PRP. RESULTS: (1) Papaverine and PGE1 directly inhibited platelet aggregation in a concentration-dependent manner. All other drugs failed to inhibit aggregation. (2) Incubation buffer of PAE cells stimulated with bradykinin showed a potent anti-aggregation. Pentobarbital concentration-dependently inhibited the endothelial cell-dependent anti-aggregation. Every other drug did not inhibit the anti-aggregation by PAE cells. CONCLUSION: Because of the direct anti-aggregatory effect without inhibiting endothelial cell-dependent anti-aggregation, we suggested that papaverine and PGE1 were the most promising vasodilators of all drugs examined in this study while further evaluation is required for the clinical relevance of the present study.

Alprostadil↗

PubMed2000

Perioperative temporal profile of cognitive function in elderly patients undergoing hip surgery.

To test the hypothesis that elderly patients who have surgery for femoral neck fractures may have delirium not only after surgery but before surgery, we prospectively investigated the perioperative temporal profile of cognitive function in such patients. We performed the Abbreviated Mental Test (AMT) six times in each patient (on the day of admission, 3 days after admission, on the day before surgery, 2 days after surgery, 7 days after surgery, and on the day of discharge). Patients were given no premedication and were anesthetized with spinal anesthesia using 0.2% hypobaric tetracaine. Of the 68 patients who were admitted because of a diagnosis of fractured neck of the femur and were scheduled to have surgery, 27 patients were subjected to analysis. Four and three patients showed a significant decrease (3 or more points) in AMT score 2 and 7 days after surgery, respectively. We conclude that surgery may have a stronger impact on cognitive function than environmental change shortly after admission in elderly patients with femoral neck fractures.

Aged↗

PubMed2000

Albumin permeability across endothelial cell monolayer exposed to reactive oxygen intermediates: involvement of reversible functional alteration of the cell membrane Ca2+ channels.

This study was designed to test the idea that the redox state of sulfhydryl (SH)-groups in cell-membrane Ca2+ channels plays a pivotal role in Ca2+ influx, which in turn causes an increase in albumin permeability across the cultured monolayer of porcine pulmonary artery endothelial (PPAE) cells exposed to xanthine/xanthine oxidase (X/XO). Albumin permeability as well as the concentration of intracellular Ca2+ ([Ca2+]i) was increased by X/XO. A H2O2 scavenger (catalase), an iron chelator (o-phenanthroline), and a hydroxyl radical scavenger (dimethyl sulfoxide) inhibited these changes provoked by X/XO, in which intracellular iron-catalyzed hydroxyl radical generation was suggested to be involved. The increase in albumin permeability and [Ca2+]i continued once the PPAE cells were exposed to X/XO. The [Ca2+]i was decreased by a Ca2+ channel blocker, Ni2+, while the removal of Ni2+ increased [Ca2+]i again, suggesting the sustained Ca2+ influx through cell-membrane Ca2+ channels was responsible for the [Ca2+]i elevation. Ni2+ failed to inhibit albumin permeability sustained after the removal of X/XO. In contrast, SH-reducing agents (dithiothreitol and glutathione) inhibited the sustained permeability as well as Ca2+ influx. We concluded that the redox alteration of SH-groups in cell-membrane Ca2+ channels was involved in the increase in albumin permeability after exposure of the endothelial cells to oxidative stress.

Albumins↗

PubMed2000

[Risk of bradycardia after endoscopic electrocautery of the upper thoracic sympathetic ganglia].

We evaluated risk of bradycardia after endoscopic electrocautery of the upper thoracic sympathetic ganglia (ETS). Enrolled in this study were 24 patients. Bradycardia, defined as heart rate below 50 beats per min continuing for more than 5 min, was found in 12 patients (50%). All patients were divided into two groups; bradycardia group and non-bradycardia group. Age, sex, region of electrocautery, fentanyl dosage, and operation time were not different between the two groups. Power spectral analysis of heart rate variability revealed that sympathetic activity decreased after ETS. Multivariate analysis indicates that postoperative-minimal heart rate depends upon preoperative heart rate at rest. We conclude that careful monitoring after ETS is necessary in a patient with heart rate below 60 bpm preoperatively.

Aged↗

PubMed2000

[Pain management for patients with cancer--current problems in a pain clinic].

One hundred and twenty-three patients with early or advanced cancer who had been referred to our pain clinic were studied retrospectively to investigate current problems with pain management for cancer patients. Pain due to advanced cancer and prolonged post-thoracotomy pain were two major reasons for referral. It was found that 51.7% of the patients with advanced cancer had not been treated appropriately with the WHO protocol for cancer pain relief before referral; however, increased administration of morphine did not necessarily relieve cancer pain, and in fact decreased the QOL of some patients; and 47.7% of patients with cancer pain were effectively treated with nerve block therapy. The present investigation also indicates that many patients who had undergone thoracotomy suffered prolonged post thoracotomy pain. Although post-thoracotomy pain was refractory to NSAIDs, trigger point injections with or without intercostal nerve block were effective in 65.4% of such patients. We conclude that further propagation of the WHO protocol for cancer pain relief, appropriate use of nerve block and establishment of practical guidelines for multidisciplinary management of pain are mandatory for improving the QOL of patients with cancer.

Aged↗

PubMed2000

[Left lung lavage affected the cardiac autonomic nervous activity more than right lung lavage during one lung ventilation in a patient with pulmonary alveolar proteinosis].

A 31-year-old man with pulmonary alveolar proteinosis underwent whole lung lavage using differential lung ventilation under general anesthesia with propofol and fentanyl. Left lung lavage was performed under the differential lung ventilation using extracorporeal lung assist. A month later, right lung lavage was performed under the differential lung ventilation alone. We compared left lung lavage with right one in the effects on heart rate variability and relationships between heart rate and arterial pressure. In the left lung lavage compared with the right one, arterial pressure was maintained higher; sympathetic nervous activity was kept tonic as shown in the power spectral analysis of heart rate variability; coherency showed lower; and a phase relationship analysis indicated a delay of almost 180 degrees. Therefore, we conclude that left lung lavage affected the cardiac autonomic nervous activity more than right one in differential lung ventilation.

Adult↗

PubMed1999

Perioperative blood transfusion as a prognostic indicator in patients with hepatocellular carcinoma.

We studied the relation of perioperative blood transfusion and the outcomes in 175 patients with hepatocellular carcinoma (HCC) who underwent hepatic resection from 1986 to 1994 in our hospital. Hepatectomy was performed in 23 (13.1%) patients with and 152 (86. 9%) without blood transfusions. The cumulative cancer-free survival rates for patients who had received blood transfusion was significantly lower than that for patients who had not received blood transfusions (p = 0.003). Further examinations revealed a significant difference in cancer-free survival rates for stage I-II patients (n = 75) of HCC (p = 0.02) but not for stage III-IV patients (n = 56) (p = 0.06). Cox regression analysis for recurrence revealed that blood transfusion was the most significant prognostic indicator (p = 0.001) for recurrence in stage I-II patients but not in stage III-IV patients (p = 0.99). These results suggest that a perioperative blood transfusion may be a significant prognostic indicator for patients with HCC who had underwent hepatectomy, especially in stage I-II patients of HCC.

Adult↗

PubMed1999

Topographical features of cutaneous tactile hypoesthetic and hyperesthetic abnormalities in chronic pain.

Tactile sensory abnormalities, such as tactile hypoesthesia and mechanical allodynia, are frequently present in patients with chronic pain. A growing body of evidence indicates that hyperesthetic phenomena, like mechanical allodynia, are at least in part due to altered processing by neurons in the CNS. We propose that the hyperesthesia is associated with a functional tactile hypoesthesia that is similarly mediated by altered processing by CNS neurons, and that this association is characterized by a particular topography that may be related to the receptive field organization of somatosensory CNS neurons. Moreover, we propose that the hyperesthetic-hypoesthetic association is dynamically modulated in tandem by pain input.

Chronic Disease↗

PubMed1999

Cytosolic Ca2+ movements of endothelial cells exposed to reactive oxygen intermediates: role of hydroxyl radical-mediated redox alteration of cell-membrane Ca2+ channels.

1. The mode of action of reactive oxygen intermediates in cysosolic Ca2+ movements of cultured porcine aortic endothelial cells exposed to xanthine/xanthine oxidase (X/XO) was investigated. 2. Cytosolic Ca2+ movements provoked by X/XO consisted of an initial Ca2+ release from thapsigargin-sensitive intracellular Ca2+ stores and a sustained Ca2+ influx through cell-membrane Ca2+ channels. The Ca2+ movements from both sources were inhibited by catalase, cell-membrane permeable iron chelators (o-phenanthroline and deferoxamine), a *OH scavenger (5,5-dimethyl-1-pyrroline-N-oxide), or an anion channel blocker (disodium 4, 4'-diisothiocyano-2, 2'-stilbenedisulphonic acid), suggesting that *O2- influx through anion channels was responsible for the Ca2+ movements, in which *OH generation catalyzed by intracellular transition metals (i.e., Haber-Weiss cycle) was involved. 3. After an initial Ca2+ elevation provoked by X/XO, cytosolic Ca2+ concentration decreased to a level higher than basal levels. Removal of X/XO slightly enhanced the Ca2+ decrease. Extracellular addition of sulphydryl (SH)-reducing agents, dithiothreitol or glutathione, after the removal of X/XO accelerated the decrement. A Ca2+ channel blocker, Ni2+, abolished the sustained increase in Ca2+, suggesting that Ca2+ influx through cell-membrane Ca2+ channels was extracellularly regulated by the redox state of SH-groups. 4. The X/XO-provoked change in cellular respiration was inhibited by Ni2+ or dithiothreitol as well as inhibitors of Haber-Weiss cycle, suggesting that Ca2+ influx was responsible for *OH-mediated cytotoxicity. We concluded that intracellular *OH generation was involved in the Ca2+ movements in endothelial cells exposed to X/XO. Cytosolic Ca2+ elevation was partly responsible for the oxidants-mediated cytotoxicity.

Animals↗