Hidenori Toyooka

The Ottawa Hospital, Ottawa, Ontario, Canada

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Publications (282)712.9 Total impact

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    Canadian Anaesthetists? Society Journal 05/2013; 60(6). DOI:10.1007/s12630-013-9960-4 · 2.31 Impact Factor
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    Yoshitaka Fujii, Hidenori Toyooka, Hiroyoshi Tanaka
    Canadian Anaesthetists? Society Journal 05/2013; 60(6). DOI:10.1007/s12630-013-9962-2 · 2.31 Impact Factor
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    Canadian Anaesthetists? Society Journal 05/2013; 60(6). DOI:10.1007/s12630-013-9961-3 · 2.31 Impact Factor
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    Yoshitaka Fujii, Hidenori Toyooka, Hiroyoshi Tanaka
    Canadian Anaesthetists? Society Journal 05/2013; 60(6). DOI:10.1007/s12630-013-9963-1 · 2.31 Impact Factor
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    Canadian Anaesthetists? Society Journal 04/2013; 60(6). DOI:10.1007/s12630-013-9958-y · 2.31 Impact Factor
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    Canadian Anaesthetists? Society Journal 04/2013; 60(6). DOI:10.1007/s12630-013-9959-x · 2.31 Impact Factor
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    Canadian Anaesthetists? Society Journal 04/2013; 60(6). DOI:10.1007/s12630-013-9946-2 · 2.31 Impact Factor
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    Canadian Anaesthetists? Society Journal 04/2013; 60(6). DOI:10.1007/s12630-013-9956-0 · 2.31 Impact Factor
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    Yoshitaka Fujii, Hidenori Toyooka
    Canadian Anaesthetists? Society Journal 04/2013; 60(6). DOI:10.1007/s12630-013-9945-3 · 2.31 Impact Factor
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    ABSTRACT: We studied the circulatory responses to laryngoscopy and tracheal intubation in 37 hypertensive patients who received nicardipine 30 μg · kg−1 iv (Group N, n = 12), diltiazem 0.3 mg · kg−1 (Group D, n = 12) or saline placebo (Group C, n = 13) 60 sec before the initiation of laryngoscopy. Anaesthesia was induced with thiopentone 5 mg · kg−1 iv, and succinylcholine 2 mg · kg−1 iv was used to facilitate tracheal intubation after precurarization with vecuronium 0.02 mg · kg−1 iv. In patients in Group C heart rate (HR) increased from 79 ± 14 (baseline) to 110 ± 12 (P < 0.05) associated with tracheal intubation; mean arterial pressure (MAP) increased from 116 ± 8 to 140 ± 77 (P < 0.05) and rate-pressure product (RPP) increased from 13385 ± 2393 to 21251 ± 3883 (P < 0.05). The changes from baseline values in HR and RPP after tracheal intubation in Group D were less than those in Groups C and N (P < 0.05). The increase in MAP following tracheal intubation in Groups N and D was lower than that in Group C (P < 0.05). We conclude that, compared with nicardipine, administration of diltiazem iv is associated with less circulatory response to tracheal intubation in hypertensive patients.
    Canadian Anaesthetists? Society Journal 11/2012; DOI:10.1007/s12630-012-9836-z · 2.31 Impact Factor
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    Yoshitaka Fujii, Hidenori Toyooka, Keisuke Amaha
    Canadian Anaesthetists? Society Journal 11/2012; 59(12). DOI:10.1007/s12630-012-9842-1 · 2.31 Impact Factor
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    Yoshitaka Fujii, Hiroyoshi Tanaka, Hidenori Toyooka
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    ABSTRACT: The prophylactic antiemetic efficacy of combined granisetron and dexamethasone was evaluated in a randomized doubleblind manner in 88 patients undergoing general anaesthesia for major gynaecological surgery. Immediately after recovery from anaesthesia, patients received a single dose of either placebo (saline, n = 22), granisetron (20 μg · kg− 1, n = 22), dexamethasone (8 mg, n = 22) or combined granisetron and dexamethasone (20 μg · kg− 1 and 8 mg, respectively, n = 22) iv. The treatment groups were similar for patient demography, surgical procedures, anaesthetics administered and opioids given. Postoperatively, the frequency of nausea was 32%, 23%, 27% and 5% after administration of placebo, granisetron, dexamethasone and granisetron plus dexamethasone, respectively; the corresponding frequencies of vomiting were 23%, 23%, 23% and 5%. The incidence of adverse events postoperatively were not different among the groups. It is concluded that prophylactic administration of combined granisetron and dexamethasone is effective in preventing postoperative nausea and vomiting after anaesthesia.
    Canadian Anaesthetists? Society Journal 11/2012; DOI:10.1007/s12630-012-9837-y · 2.31 Impact Factor
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    Canadian Anaesthetists? Society Journal 11/2012; 59(12). DOI:10.1007/s12630-012-9843-0 · 2.31 Impact Factor
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    Yoshitaka Fujii, Hidenori Toyooka, Keisuke Amaha
    Canadian Anaesthetists? Society Journal 11/2012; DOI:10.1007/s12630-012-9838-x · 2.31 Impact Factor
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    Yoshitaka Fujii, Hiroyoshi Tanaka, Hidenori Toyooka
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    ABSTRACT: The effects of laryngeal mask airway (LMA) insertion and tracheal intubation on circulatory responses were studied in normotensive (n = 24) and hypertensive (n = 22) patients. In a randomized, double-blind manner, LMA insertion or tracheal intubation was performed after induction of anaesthesia with thiopentone and muscle relaxation with succinylcholine. In both normotensive and hypertensive patients, heart rate (HR), mean arterial pressure (MAP) and rate-pressure product increased after tracheal intubation or LMA insertion compared with base-line (P < 0.05). The haemodynamic changes were greater after intubation than after LMA insertion (P < 0.05). Following intubation of the trachea or insertion of the LMA, HR increased more markedly in hypertensive patients than in normotensive patients (P < 0.05). Plasma adrenaline and noradrenaline concentrations after tracheal intubation or LMA insertion increased compared with baseline values (P < 0.05) in normotensive and hypertensive patients. The increase in noradrenaline concentration after tracheal intubation was greater than that after LMA insertion (P < 0.05). No patient revealed ECG evidence of myocardial ischaemia. We conclude that insertion of LMA is associated with less circulatory responses than tracheal intubation in both normotensive and hypertensive patients.
    Canadian Anaesthetists? Society Journal 11/2012; DOI:10.1007/s12630-012-9839-9 · 2.31 Impact Factor
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    Yoshitaka Fujii, Hiroyoshi Tanaka, Hidenori Toyooka
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    ABSTRACT: The antiemetic effects of granisetron, a selective 5-hydroxy-tryptamine type 3 receptor antagonist, on postoperative nausea and vomiting were studied and compared with placebo and metoclopramide in 60 patients undergoing general anaesthesia for major gynaecological surgery. The patients received a single iv dose of either granisetron (3 mg, n = 20) metoclopramide (10 mg, n = 20), or placebo (saline, n = 20) immediately after recovery from anaesthesia. The effects were assessed during the first three and the next 21 hr after recovery from anaesthesia by means of a nausea and vomiting score; 0 = no emetic symptoms, 1 = nausea, 2 = vomiting. The mean scores during 0–3 hr were 0.8, 0.1 and 0.1 after administration of placebo, metoclopramide and granisetron, respectively; the corresponding scores during 3–24 hr were 0.6, 0.5 and 0.1. The scores of the metoclopramide and the granisetron groups were different from the placebo group in the first three hours (P < 0.05). Although there were no differences in the scores during 0–3 hr between the metoclopramide and the granisetron groups, there were differences during 3–24 hr (P < 0.05). It is concluded that granisetron is superior to metoclopramide in the long-term prevention of postoperative nausea and vomiting after anaesthesia.
    Canadian Anaesthetists? Society Journal 11/2012; 59(12). DOI:10.1007/s12630-012-9841-2 · 2.31 Impact Factor
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    Yoshitaka Fujii, Hiroyoshi Tanaka, Hidenori Toyooka
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    ABSTRACT: Purpose Dexamethasone decreases chemotherapy-induced emesis when added to antiemetic regimens. This study was designed to compare the effectiveness of granisetron and dexamethasone with granisetron alone in the prevention of postoperative vomiting after strabismus repair, tonsillectomy with or without adenoidectomy in children. Methods In a randomized, double-blind study, 60 healthy children, 4–10 yr of age, received either granisetron 40 μg · kg−1 and saline (Group S) or granisetron 40 μg · kg−1 and dexamethasone 4 mg (Group D) iv immediately after the induction of anaesthesia. All subjects received anaesthetics consisting of sevoflurane and nitrous oxide in oxygen. Postoperative pain was treated with acetaminophen pr or pentazocine iv. Postoperatively, during the first 24 hr after anaesthesia, the frequencies of retching and vomiting, and the incidence of adverse events were recorded by nursing staff. Results There were no differences between the treatment groups with regard to demographics, surgical procedure, anaesthetic administered or analgesics used for postoperative pain. The frequency of the symptoms was 27% and 7% in Groups S and D, respectively (P < 0.05). The incidence of adverse events was comparable in the two groups. Conclusion The prophylactic administration of granisetron and dexamethasone was more effective than granisetron alone in the prevention of postoperative vomiting in paediatric subjects undergoing strabismus repair, tonsillectomy and adenoidectomy.
    Canadian Anaesthetists? Society Journal 11/2012; DOI:10.1007/s12630-012-9829-y · 2.31 Impact Factor
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    Yoshitaka Fujii, Hidenori Toyooka, Hiroyoshi Tanaka
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    ABSTRACT: Purpose This study was to identify the minimum effective dose of granisetron, a selective 5-hydroxytryptamine type 3 receptor antagonist, to prevent postoperative vomiting in children who have undergone strabismus repair, tonsillectomy or tonsillectomy with adenoidectomy. Methods In a randomized, double-blind fashion, 80 healthy children aged 4–10 yr were assigned to receive either placebo (saline) or granisetron in a dose of 20, 40 or 80 μg· kg−1 iv immediately following the induction of anaesthesia. All subjects received a standardized anaesthetic, which consisted of sevoflurane in nitrous oxide and oxygen. Rescue antiemetics were administered if two or more episodes of vomiting occurred. Postoperative pain was treated with acetaminophene pr or pentazocine iv. During the first 24 hr after anaesthesia, the frequencies of retching and vomiting were recorded in a standardized fashion by nursing staff while subjects were in a hospital. Results There were no differences among four treatment groups with regard to subject characteristics, surgical procedures, anaesthetic and postoperative management or adverse effects. The frequencies of these symptoms were as follows: 65%, 60%, 20% and 15% after administration of placebo, granisetron 20, 40 or 80 μg· kg−1. Three children who had received either placebo or granisetron 20 μg · kg−1 required another rescue antiemetic drug, whereas none who had received granisetron 40 or 80 μg · kg−1 needed rescue drugs. Conclusion Granisetron 40 μg · kg−1 is an effective antiemetic for preventing retching and vomiting following strabismus repair and tonsillectomy in children. Increasing the dose to 80 μg ·kg −1 provided no demonstrable benefit in reducing postoperative emesis.
    Canadian Anaesthetists? Society Journal 11/2012; DOI:10.1007/s12630-012-9831-4 · 2.31 Impact Factor
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    Yoshitaka Fujii, Hidenori Toyooka, Hiroyoshi Tanaka
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    ABSTRACT: Purpose This randomized, placebo-controlled, double-blind study was to evaluate the effects of granisetron, a selective 5-hydroxytryptamine type 3 receptor antagonist, for preventing postoperative nausea and vomiting in 110 patients with (n = 50) and without (n = 60) a history of motion sickness undergoing general anaesthesia for major gynaecological surgery. Methods The patients received a single dose of either granisetron (40 μg · kg−1) or placebo (saline) iv over 2–5 min immediately before induction of anaesthesia. Postoperatively, during the first 24 hr after anaesthesia, the frequencies of nausea and vomiting were recorded. Results Except for a positive history of motion sickness, the treatment groups were similar for patient characteristics, types of surgery, anaesthetics administered and opioids given. Postoperatively, the frequency of nausea was 44% and 16% after administration of placebo and granisetron in patients with motion sickness, and was 30% and 7% in patients without it, respectively; the corresponding frequencies of vomiting were 28%, 8%, 13% and 3%. The incidence of adverse events postoperatively were not different among the groups. Conclusion These results suggest that preoperative prophylactic administration of granisetron is effective and safe for preventing postoperative nausea and vomiting in patients with motion sickness as well as in patients without it.
    Canadian Anaesthetists? Society Journal 11/2012; DOI:10.1007/s12630-012-9832-3 · 2.31 Impact Factor
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    Yoshitaka Fujii, Hiroyoshi Tanaka, Hidenori Toyooka
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    ABSTRACT: The effects of granisetron for preventing postoperative nausea and vomiting were investigated in a randomized, double-blind comparison with droperidol and placebo in 100 patients undergoing general anaesthesia for major gynaecological surgery. The patients received a single dose of either granisetron (40 μg · kg− 1, n = 25), dropéridol (1.25 mg, n = 25; 2.5 mg n = 25) or placebo (saline, n = 25) iv over two to five minutes immediately before induction of anaesthesia. The antiemetic effects of these drugs were evaluated during the first three and the next 21 hr after recovery from anaesthesia. During 0– 3 hr after anaesthesia, the frequency of nausea and vomiting was 60%, 12%, 16% and 12% after administration of placebo, granisetron, droperidol 1.25 mg or droperidol 2.5 mg, respectively. The corresponding frequencies during 3– 24 hr after anaesthesia were 44%, 8%, 36% and 12%. The efficacy of granisetron in preventing postoperative nausea and vomiting was almost equal to that of droperidol 2.5 mg. The awakening time in the patients who had received droperidol 2.5 mg was prolonged by approximately three minutes compared with the placebo group (P < 0.05), and postoperative drowsiness/sedation was observed in these patients. In conclusion, preoperative prophylactic administration of granisetron is superior to that of droperidol in the prevention of postoperative nausea and vomiting after anaesthesia.
    Canadian Anaesthetists? Society Journal 11/2012; DOI:10.1007/s12630-012-9834-1 · 2.31 Impact Factor

Publication Stats

3k Citations
712.90 Total Impact Points

Institutions

  • 2012–2013
    • The Ottawa Hospital
      Ottawa, Ontario, Canada
    • Tsukuba Memorial Hospital
      Tsukuba, Ibaraki, Japan
  • 1998–2013
    • University of Tsukuba
      • • Department of Anesthesiology
      • • Institute of Clinical Medicine
      Tsukuba, Ibaraki-ken, Japan
  • 1987–2012
    • Tokyo Medical and Dental University
      • • Department of Medicine
      • • Faculty of Medicine
      • • Department of Critical Care Medicine
      • • Department of Anesthesiology
      Edo, Tōkyō, Japan
  • 2011
    • Teikyo University Hospital
      Edo, Tōkyō, Japan
  • 2006
    • Teikyo University
      • Department of Anesthesiology
      Edo, Tōkyō, Japan
  • 2003–2005
    • St. Luke's International Hospital
      Edo, Tōkyō, Japan
  • 1999
    • Hamamatsu University School of Medicine
      Hamamatu, Shizuoka, Japan
  • 1990
    • Tokyo Metropolitan Hiroo Hospital
      Edo, Tōkyō, Japan