Biomedical subjects

H Toyooka

Publications and source records attributed to H Toyooka.

At least 55 records · Page 3Linked to original sources

PubMed2000

[Preparation and clinical evaluation of orally-disintegrating clonidine hydrochloride tablets for preanesthetic medication].

Orally-disintegrating tablets of clonidine hydrochloride, an alpha 2-adrenergic agonist, were prepared by the method of drying an aqueous suspension. The suspension was prepared using powdered lactose, and the composition ratio was 2:1 (powdered lactose: 0.048% clonidine hydrochloride solution). The suspension was dried under 4 +/- 1 degrees C (72 +/- 15% R.H.). We obtained tablets containing clonidine hydrochloride (40 micrograms/tablet). Physical properties of the tablets were as follows: hardness was 4.0 kgf, and disintegration time was 41.7 s (in vitro). In the clinical use, 8 patients, aged 1-2 year and weighing 9-11 kg, received approximately 4 micrograms/kg body weight as clonidine hydrochloride. The tablet was administered 90 min before entering the operating room. All patients were willing to accept the tablet. The quality of separation from parents, sedation and a mask acceptance were excellent on all patients. These results suggest that the orally-disintegrating tablet of clonidine hydrochloride was useful in a clinical situation for the preanesthetic medication of pediatric patients aged 1-2 year.

Administration, Oral↗

PubMed2000

[Complications of hysteroscopical myomectomy: a report of two cases].

Hysteroscopical myomectomy has recently become popular in Japan. We present two patients who developed water intoxication and air embolism during surgery. [Case 1] Hysteroscopical myomectomy was performed under general anesthesia in a 37-yr-old woman (ASA I). Three hours after the start of the surgery, the patient's serum sodium concentration dropped to 118 mEq.l-1. She was treated with furosemide and recovered without sequelae. [Case 2] A 39-yr-old woman (ASA I) was scheduled to have hysteroscopical myomectomy under spinal and epidural anesthesia. Forty-five minutes after the start of the surgery, the patient complained of severe back pain, her blood pressure decreasing to 40 mmHg, SpO2 decreased to 80%, and ECG showed atrial fibrillation. After administration of ephedrine 5 mg, she recovered within 20 min. No abnormality was observed in echocardiogram, although some negative spots were detectable in a lung scintigraphy. She was discharged without sequelae. The hysteroscopical procedure is considered a non-invasive surgery, but the cases presented here emphasize the necessity for close attention to complications, especially pulmonary embolism.

Adult↗

PubMed1999

Early oral intake after arthroscopic surgery under spinal anesthesia.

PURPOSE: We investigated the tolerability of early oral feeding (EOF) and its effects on the recovery of bowel function after spinal anesthesia. METHODS: Thirty-one healthy adult patients undergoing knee arthroscopy or arthroscopic surgeries were randomly assigned to either the EOF group (n = 16) or the nil per os (NPO, n = 15) group. Spinal anesthesia was performed using hyperbaric tetracaine solution in all patients. Patients in the EOF group were allowed free access to solid and liquid food immediately after surgery before analgesia from spinal tetracaine resolved. Oral intake was prohibited for 24 h after completion of surgery in the NPO group. RESULTS: Two patients in each group were mildly nauseated without the need for treatment. While degree of appetite determined by a visual analog scale before the first meal and time to the first gas emission showed no significant differences between groups, the median time to the first defecation in the EOF group (20.6 h) was significantly shorter than that of the NPO group (33.5 h, P = 0.005). No other complications associated with anesthesia, surgery, or EOF were noted. CONCLUSION: Our results suggest that the restriction of EOF after surgery not involving the gastrointestinal tract under spinal anesthesia may not be rational, and that EOF may facilitate recovery of bowel function.

Clinical Trial↗

PubMed1999

Heme oxygenase-1 expression in oral squamous cell carcinoma as involved in lymph node metastasis.

Thirty-eight oral squamous cell carcinomas (SCCs) were semi-quantitatively analyzed by immunohistochemical staining, and the relation between heme oxygenase-1 (HO-1) expression and the clinical status were correlated. High immunostaining of HO-1 was detected in lymph node metastasis negative groups (P = 0.0018) and in well-differentiated SCCs (P = 0.0016). There were no significant correlations between heme oxygenase-1 expression and other factors, such as size of the tumor, staging, age and sex. These findings further support the proposition that high heme oxygenase-1 expression in oral SCCs can be useful in identifying patients at low risk of lymph node metastasis.

Adult↗

PubMed1999

Combined diltiazem and lidocaine reduces cardiovascular responses to tracheal extubation and anesthesia emergence in hypertensive patients.

PURPOSE: Hypertensive patients exhibit exaggerated cardiovascular responses to tracheal extubation. This study was undertaken to compare the efficacy of combined diltiazem and lidocaine with each drug alone in suppressing the hemodynamic changes during tracheal extubation. METHODS: Sixty hypertensive patients (ASA II), defined as systolic blood pressure > 160 mmHg and/or diastolic blood pressure > 95 mmHg (WHO), undergoing elective orthopedic surgery received, in a randomized, double-blind manner, 0.2 mg x kg(-1) diltiazem, 1.0 mg x kg(-1) lidocaine, or 0.2 mg x kg(-1) diltiazem plus 1.0 mg x kg(-1) lidocaine (n=20 of each) i.v. before tracheal extubation. Changes in heart rate (HR), mean arterial pressure (MAP) and rate-pressure product (RPP) were measured before and after tracheal extubation. RESULTS: Hemodynamic changes during tracheal extubation were less in patients receiving diltiazem plus lidocaine than in those receiving diltiazem or lidocaine as a sole medicine (RPP; 10322 +/- 1674 (combined) vs 11532 +/- 1802 (diltiazem), 15388 +/- 2050 (lidocaine), mean +/- SD, P < 0.05). CONCLUSION: Combined diltiazem and lidocaine is more effective prophylaxis than diltiazem or lidocaine alone for attenuating the cardiovascular responses to tracheal extubation and emergence from anesthesia in hypertensive patients.

Aged↗

PubMed1999

Ramosetron vs granisetron for the prevention of postoperative nausea and vomiting after laparoscopic cholecystectomy.

PURPOSE: To compare the efficacy of ramosetron with granisetron for the prevention of postoperative nausea and vomiting (PONV) after laparoscopic cholecystectomy. METHODS: In a randomized, double-blind study, 80 female inpatients received 3 mg granisetron or 0.3 mg ramosetron i.v. (n=40 of each) at the completion of surgery The standardized anesthetic included isoflurane and nitrous oxide in oxygen. RESULTS: Complete response, defined as no PONV, during the first 24 hr (0-24 hr) after anesthesia was 85% with granisetron and 93% with ramosetron, respectively (P=0.241); the corresponding incidence during the next 24 hr (24-48 hr) after anesthesia was 63% and 90% (P=0.004). No clinically important adverse events due to the study drug were observed in any of the groups. CONCLUSION: Ramosetron was more effective than granisetron for prevention of PONV during 0-48 hr after anesthesia for laparoscopic cholecystectomy.

Adult↗

PubMed1999

Landiolol decreases a dysrhythmogenic dose of epinephrine in dogs during halothane anesthesia.

PURPOSE: To examine the effect of landiolol (ONO-1101), a new ultra-short acting and highly selective beta blocker, on epinephrine-induced ventricular arrhythmias in halothane-anesthetized dogs. METHODS: We administered five different doses (0, 0.1, 0.5, 1.0, 10 microg x kg(-1) x min(-1)) landiolol and determined the dysrhythmogenic dose of epinephrine (DDE), defined as the smallest dose producing four or more PVCs within 15 sec, at each dose of landiolol and after cessation of infusion. RESULTS: The control value of DDE during 1.3 MAC halothane anesthesia was 1.26 +/- 0.44 (mean +/- SD) microg x kg(-1) x min(-1) and the corresponding plasma concentration of epinephrine (PCE) was 12.2 +/- 8.3 ng x ml(-1). Concomitant administration of 10 microg x kg(-1) x min(-1) landiolol increased DDE and corresponding PCE (P < 0.05). At 30 min after cessation of landiolol infusion, DDE and corresponding PCE returned to the control values. CONCLUSIONS: Landiolol, at a dose of 10 microg x kg(-1) x min(-1), has an antiarrhythmic effect on epinephrine-induced ventricular arrhythmias in dogs during anesthesia with halothane.

Adrenergic beta-Agonists↗

PubMed1999

Prophylactic antiemetic therapy with droperidol in patients undergoing laparoscopic cholecystectomy.

PURPOSE: The incidence of postoperative nausea and vomiting (PONV) following laparoscopic cholecystectomy (LC) is relatively high when no prophylactic antiemetic is given. We have studied the efficacy of a commonly used and well-established antiemetic, droperidol, for the prevention of PONV in patients undergoing LC. METHODS: In a randomized, double-blind, placebo-controlled study, 60 patients received placebo (saline) or droperidol 50 microg.kg(-1) (maximum dose, 2.5 mg) intravenously immediately before the induction of anesthesia (n = 30 of each). A standard general anesthetic technique was employed throughout. RESULTS: A complete response, defined as no PONV and no need for another rescue antiemetic medication during the first 24 h after anesthesia, was 57% and 83% in patients who had received placebo and droperidol 50 microg.kg(-1), respectively ( P < 0.05). No clinically serious adverse events were observed in any of the groups. CONCLUSION: Prophylactic antiemetic therapy with droperidol 50 microg.kg(-1) (maximum dose, 2.5 mg) is highly effective for preventing PONV after LC.

Clinical Trial↗

PubMed1999

Combination of granisetron and droperidol in the prevention of nausea and vomiting after middle ear surgery.

STUDY OBJECTIVES: To evaluate the efficacy and safety of granisetron-droperidol combination for the prevention of postoperative nausea and vomiting (PONV) after middle ear surgery. DESIGN: Prospective, randomized, double-blind study. SETTING: University hospital. PATIENTS: 150 ASA physical status I patients (108 females, 42 males) scheduled for elective middle ear surgery. INTERVENTIONS: Patients received granisetron 40 micrograms/kg (n = 50), droperidol 20 micrograms/kg (n = 50), or granisetron 40 micrograms/kg plus droperidol 20 micrograms/kg (n = 50) intravenously immediately before induction of anesthesia. MEASUREMENTS AND MAIN RESULTS: A standard general anesthetic technique and postoperative analgesia were used throughout the study. A complete response, defined as no PONV and no need for another rescue antiemetic, from 0 to 3 hours after anesthesia occurred in 78%, 56%, and 94% of patients who had received granisetron, droperidol, and granisetron plus droperidol, respectively. The corresponding incidence between 3 and 24 hours after anesthesia was 80%, 52% and 94%. Thus, a complete response within the first 24-hour postanesthetic period was greater in patients receiving granisetron-droperidol combination than in those receiving granisetron alone or droperidol alone (p < 0.05). No clinically adverse events were observed in any of the groups. CONCLUSIONS: A combination of granisetron and droperidol is more effective than droperidol or granisetron alone for the prevention of PONV after middle ear surgery.

Adult↗

PubMed1999

Anti-emetic efficacy of prophylactic granisetron compared with perphenazine for the prevention of post-operative vomiting in children.

We have compared the efficacy of granisetron with perphenazine in the prevention of vomiting after tonsillectomy with or without adenoidectomy in children. In a prospective, randomized, double-blind study, 90 paediatric patients, ASA I, aged 4-10 years, received granisetron 40 mg kg-1 or perphenazine 70 mg kg-1 (n = 45 each) intravenously immediately after an inhalation induction of anaesthesia. A standard general anaesthetic technique was employed throughout. A complete response, defined as no emesis with no need for another rescue antiemetic, during the first 3 h (0-3 h) after anesthesia was 87% with granisetron and 78% with perphenazine (P = 0.204). The corresponding incidence during the next 21 h (3-24 h) after anaesthesia was 87% and 62% (P = 0.007). No clinically serious adverse events were observed in any of the groups. We conclude that granisetron is a better anti-emetic than perphenazine for the long-term prevention of post-operative vomiting in children undergoing general anaesthesia for tonsillectomy.

Adenoidectomy↗

PubMed1999

Prophylactic therapy with combined granisetron and dexamethasone for the prevention of post-operative vomiting in children.

This study was undertaken to compare the efficacy and safety of granisetron, a 5-hydroxytryptamine type 3 receptor antagonist, and dexamethasone and each drug alone for the prevention of post-operative vomiting by children, with no history of motion sickness and/or previous post-operative vomiting, undergoing general inhalational anaesthesia for surgery (inguinal hernia and phimosis). In a randomized, double-blind manner, 150 children, ASA physical status 1, aged 4-10 years, were assigned to receive granisetron 40 mg kg-1, dexamethasone 150 mg kg-1, or granisetron 40 mg kg-1 plus dexamethasone 150 mg kg-1 intravenously immediately after inhalation induction of anaesthesia (n = 50 of each). A complete response, defined as no emesis and no need for another rescue anti-emetic during the first 24 h after anaesthesia, was 86% with granisetron, 68% with dexamethasone and 98% with granisetron plus dexamethasone, respectively (P < 0.05; overall Fisher's exact probability test). No clinically serious adverse events were observed in any of the groups. In conclusion, prophylactic therapy with combined granisetron and dexamethasone was more effective than was each anti-emetic alone for the prevention of vomiting after paediatric surgery.

Anesthesia, Inhalation↗

PubMed1999

Milrinone enhances the contractility of fatigued diaphragm in dogs: a dose-ranging study.

The dose-related effects of milrinone, a phosphodiesterase (PDE) III inhibitor, on the contractility of fatigued diaphragm were studied in dogs. Animals were divided into three groups of eight each. Diaphragmatic fatigue was induced by intermittent supramaximal bilateral electrophrenic stimulation at a frequency of 20 Hz applied for 30 min. After the production of fatigue, Group I received no study drug; Group II was infused with milrinone (50 mg kg-1 loading dose plus 0.2 mg kg-1 min-1 maintenance dose); Group III was infused with milrinone (50 mg kg-1 loading dose plus 0.5 mg kg-1 min-1 maintenance dose). Diaphragmatic contractility was assessed by measurement of transdiaphragmatic pressure. After the fatigue-producing period, transdiaphragmatic pressure at low-frequency stimulation (20-Hz) decreased from the prefatigued values in all groups (P < 0.05), whereas transdiaphragmatic pressure at high-frequency (100-Hz) stimulation did not change. Compared with Group I, transdiaphragmatic pressure to each stimulus increased during milrinone infusion in Groups II and III (P < 0.05). The increase in trans-diaphragmatic pressure was greater in Group III than in Group II (P < 0.05). It is concluded that milrinone is associated with a dose-related effect on the contractility of fatigued diaphragm in dogs.

Animals↗

PubMed1999

Prevention of post-operative nausea and vomiting with combined granisetron and droperidol in women undergoing thyroidectomy.

We have compared the efficacy and safety of combined granisetron and droperidol with each anti-emetic alone for preventing post-operative nausea and vomiting after thyroidectomy. In a prospective, randomized, double-blind study, 180 women received granisetron 40 micrograms kg-1, droperidol 20 micrograms kg-1, or granisetron 40 micrograms kg-1 plus droperidol 20 micrograms kg-1 (n = 60 of each) intravenously immediately before induction of anaesthesia. A standard general anaesthetic technique and post-operative analgesia were used. A complete response, defined as no post-operative nausea and vomiting and no need for another rescue anti-emetic, during the first 24 h after anaesthesia occurred in 88%, 60% and 98% of patients who had received granisetron, droperidol and granisetron plus droperidol (P < 0.05; overall Fisher's exact probability test). No clinically important adverse events due to the drugs were observed in any of the groups. In summary, prophylactic use of combined granisetron and droperidol is more effective than each drug alone for the prevention of post-operative nausea and vomiting in female patients undergoing thyroidectomy.

Adult↗

PubMed1999

Combination of granisetron and droperidol for the prevention of vomiting after paediatric strabismus surgery.

This study was undertaken to compare the efficacy of granisetron plus droperidol with each antiemetic alone for the prevention of vomiting after paediatric strabismus surgery. In a prospective, randomized, double-blinded trial, 120 ASA physical status I children, aged 4-10 years, received granisetron 40 microg.kg- 1, droperidol 50 microg.kg- 1, granisetron 40 microg.kg- 1 plus droperidol 50 microg.kg- 1 (n=40 of each) intravenously after an inhalation induction of anaesthesia. A complete response, defined as no vomiting, no retching and no need for another rescue antiemetic medication, during 0-3 h after anaesthesia was 80% with granisetron, 45% with droperidol and 98% with granisetron plus droperidol, respectively; the corresponding incidence during 3-24 h after anaesthesia was 78%, 38% and 98% (P< 0.05; overall chi-squared test with Yates continuity correction). No clinically important adverse events were observed in any of the groups. In conclusion, a combination of granisetron and droperidol was more effective than granisetron or droperidol as a sole antiemetic for the prevention of postoperative vomiting in children undergoing strabismus repair.

Analysis of Variance↗

PubMed1999

Prevention of postoperative vomiting with granisetron in paediatric patients with and without a history of motion sickness.

A history of motion sickness is one of the patient-related factors associated with postoperative emesis. This prospective, randomized, double-blind, placebo-controlled study was undertaken to assess the efficacy of granisetron, a selective 5-hydroxytryptamine type 3 receptor antagonist, for preventing postoperative vomiting after tonsillectomy in 120 children with (n = 60) and without (n = 60) a history of motion sickness. Patients received a single dose of granisetron (40 micrograms.kg-1) or placebo (saline) (n = 30 of each) intravenously after an inhalation induction of anaesthesia. A complete response, defined as no vomiting, no retching and no need for another rescue medication, during the first 24 h after anaesthesia was 77% and 13% in patients with a history of motion sickness who had received granisetron or placebo, respectively; the corresponding incidence was 83% and 40% in those without it (P < 0.05; chi 2 test with Yates' continuity correction). No clinically serious adverse effects due to the study drug were observed in any of the groups. In conclusion, prophylactic antiemetic therapy with granisetron is effective for preventing postoperative emesis in children with a history of motion sickness as well as in those without it.

Antiemetics↗

PubMed1999

Flumazenil antagonizes midazolam-induced airway narrowing during nasal breathing in humans.

We measured nasal resistance (Rn) while awake, during midazolam-induced sedation and after antagonism with flumazenil (n = 9). Nasal and oral airflow were measured. Rn was calculated by dividing the difference between maximal nasal mask and oropharyngeal pressures by inspiratory airflow at minimum pharyngeal pressure. During sedation, two subjects developed obstructive apnoeic events and four subjects had snoring events. Each apnoea was ended by mechanisms other than a change in breathing route. After antagonism with flumazenil, apnoeic and snoring events were abolished. Rn during midazolam sedation (median 1.46 (25th percentile 1.00, 75th 2.61) kPa litre-1 s) was significantly greater than before midazolam (0.29 (0.25, 0.48) kPa litre-1 s) and after flumazenil (0.41 (0.25, 0.58) kPa litre-1 s) (P < 0.01 in each subject). We conclude that midazolam increased Rn, sometimes leading to obstruction, and flumazenil abolished this increase in Rn.

Adult↗

PubMed1999

End-tidal sevoflurane concentration for tracheal extubation (MACEX) in adults: comparison with isoflurane.

Sevoflurane has a non-pungent odour and provides smooth induction of anaesthesia. In contrast, isoflurane is irritating to the airway when used for induction, and this may also be evident during emergence from anaesthesia. We measured the end-tidal concentration of anaesthetic that prevented response to extubation in 50% of patients (MACEX) in adults receiving either sevoflurane or isoflurane. Airway complications during emergence from anaesthesia were also noted. We studied 51 adult patients, ASA 1, aged 36-59 yr. Patients received sevoflurane (n = 29) or isoflurane (n = 22) for elective intraocular surgery. The concentration at which extubation was attempted was determined by a modification of Dixon's up-and-down method. When tracheal extubation was accomplished without coughing and gross purposeful muscular movements within 1 min after extubation, it was considered a smooth tracheal extubation. Patients who developed breath-holding or laryngospasm immediately after tracheal extubation were regarded as not having been extubated smoothly. In addition, patients were observed for respiratory events during the remainder of the emergence period. MACEX values for sevoflurane and isoflurane were 1.07% and 0.83%, respectively. ED95 values of sevoflurane and isoflurane were 2.04% and 1.19%, respectively. In 12 patients in the isoflurane group, extubation was smooth but six patients had coughing episodes during the remainder of the emergence period. In contrast, one of 15 patients in the sevoflurane group in whom tracheal extubation was smooth coughed later (P = 0.035). Airway obstruction was frequent when tracheal extubation was performed at end-tidal concentrations exceeding 1 MACEX for each anaesthetic.

Adult↗

PubMed1999

Bleeding from a tear in the gastric mucosa caused by transoesophageal echocardiography during cardiac surgery: effective haemostasis by endoscopic argon plasma coagulation.

We present an unusual complication of transoesophageal echocardiography (TOE) during cardiac surgery. Although the patient had no oesophageal or gastrointestinal disease, a gastric mucosal tear of approximately 2 cm long occurred in the mucosa just distal to the gastrooesophageal junction caused by the TOE probe. Bleeding from the tear was stopped using endoscopic argon plasma coagulation.

Argon↗