Biomedical subjects

H Toyooka

Publications and source records attributed to H Toyooka.

At least 73 records · Page 4Linked to original sources

PubMed1999

Granisetron/dexamethasone combination for reducing nausea and vomiting during and after spinal anesthesia for cesarean section.

UNLABELLED: We compared the efficacy of granisetron plus dexamethasone with that of granisetron alone for preventing nausea and vomiting in parturients undergoing cesarean section under spinal anesthesia. In a randomized, double-blinded manner, 120 patients received either granisetron 3 mg (Group I, n = 60) or granisetron 3 mg plus dexamethasone 8 mg (Group II, n = 60) IV immediately after clamping of the fetal umbilical cord. A complete response, defined as no emetic symptoms and no need for another rescue antiemetic medication in the intraoperative, postdelivery period was 83% in Group I and 98% in Group II (P = 0.008); the corresponding rates during the first 24 h after surgery was 85% and 98% (P = 0.016). No clinically serious adverse events were observed in any of the groups. In conclusion, the prophylactic use of a granisetron/dexamethasone combination is more effective than granisetron alone for reducing nausea and vomiting in patients during and after spinal anesthesia for cesarean section. IMPLICATIONS: Intraoperative, postdelivery, and postoperative nausea and vomiting are distressing to patients undergoing cesarean section under spinal anesthesia. The combination of granisetron plus dexamethasone was evaluated and found to be effective for preventing these emetic symptoms.

Adult↗

PubMed1999

The effects of clonidine premedication on sevoflurane requirements and anesthetic induction time.

UNLABELLED: We assessed the effects of oral clonidine preanesthetic medication (4.5 microg/kg) on the vital capacity rapid-inhalation anesthetic induction time (VCRII time) and minimum alveolar anesthetic concentration (MAC) to prevent a response to a verbal command in 50% of patients (MAC-Awake) by its hypnotic effect, and on MAC-Skin incision for the analgesic effect in patients anesthetized with sevoflurane. We studied 104 adult patients (control group: n = 52, clonidine group: n = 52) aged 30-48 yr scheduled to undergo general anesthesia. Fifty-two patients received oral clonidine 4.5 microg/kg 1.5 h before arrival in the operating room (clonidine group). The patients exhaled to residual volume and took three vital capacity breaths of 5% sevoflurane in oxygen. The VCRII time was defined as the time interval between the initiation of the VCRII and the disappearance of the response to verbal command. Anesthesia was maintained with sevoflurane in oxygen and air. The end-tidal (ET) sevoflurane concentration reached a predetermined value, then the ratio of predetermined ET to inspiratory concentration was maintained at > or =0.95 for at least 15 min before skin incision. After skin incision, the patients were observed for gross purposeful muscular movements. MAC was defined as the average of the cross-over midpoints in each cross-over. After maintaining the ET sevoflurane concentration for 15 min, patients were judged to be awake or asleep. Average times for VCRII using 5% sevoflurane were achieved in 44+/-11 s (mean +/- SD) and 27+/-6 s in the control and clonidine groups, respectively (P = 0.0001). MAC-Awake values of sevoflurane were 0.66%+/-0.03% and 0.35%+/-0.02% (P = 0.0001), and MAC-Skin incision values were 1.97%+/-0.19% and 1.29%+/-0.13% (P = 0.0001) in the control and clonidine groups, respectively. These results suggest that clonidine may have a more potent hypnotic effect than analgesic effect. IMPLICATIONS: Oral clonidine preanesthetic medication (4.5 microg/kg) significantly reduces vital capacity rapid inhalation anesthetic induction time and minimum alveolar anesthetic concentration awake for sevoflurane.

Adult↗

PubMed1999

Comparison of ramosetron and granisetron for preventing postoperative nausea and vomiting after gynecologic surgery.

UNLABELLED: In a prospective, randomized, double-blinded study, we evaluated the efficacy of granisetron and ramosetron for preventing postoperative nausea and vomiting (PONV) in major gynecologic surgery. One hundred twenty patients, ASA physical status I or II, aged 23-65 yr, received i.v. granisetron 2.5 mg or ramosetron 0.3 mg (n = 60 each) at the end of surgery. A standard general anesthetic technique and postoperative analgesia were used. The incidence of a complete response, defined as no PONV and no need for another rescue medication, 0-3 h after anesthesia was 87% with granisetron and 90% with ramosetron; the corresponding incidence 3-24 h after anesthesia was 85% and 90%; the corresponding incidence 24-48 h after anesthesia was 70% and 92% (P < 0.05). No clinically serious adverse events due to the drugs were observed in any of the groups. In conclusion, prophylactic therapy with ramosetron is more effective than granisetron for the longterm prevention of PONV after major gynecologic surgery. IMPLICATIONS: We compared the efficacy of granisetron and ramosetron for preventing postoperative nausea and vomiting in major gynecologic surgery. Prophylactic therapy with ramosetron was more effective than granisetron for preventing postoperative nausea and vomiting 24-48 h after anesthesia.

Adult↗

PubMed1999

Fentanyl pretreatment does not impair the reliability of an epinephrine-containing test dose during propofol-nitrous oxide anesthesia.

UNLABELLED: We designed this study to determine the hemodynamic responses to and the efficacy of a simulated IV test dose during propofol anesthesia based on the conventional heart rate (HR; positive if increase > or =20 bpm), the modified HR (positive if increase > or =10 bpm), and the systolic blood pressure (SBP; positive if increase > or =15 mm Hg) criteria. Eighty healthy patients were randomized to receive 2 mg/kgpropofol or propofol plus fentanyl (100 microg) at the induction of anesthesia (n = 40 each). After endotracheal intubation, anesthesia in both groups was maintained with propofol 8 mg x kg(-1) x h(-1) and 67% nitrous oxide in oxygen. Each group of patients was further divided into a test dose group receiving 1.5% lidocaine 3 mL plus epinephrine 15 microg (1:200,000) or a saline group (n = 20 each) receiving 3 mL of isotonic sodium chloride solution i.v. HR and SBP were monitored for 4 min after the i.v. injection of the study drug. The i.v. injection of the test dose produced a HR increase > or =20 bpm in 20 and 17 patients in the propofol and propofol-fentanyl groups, respectively, whereas all patients receiving the test dose and none receiving saline had HR increases > or =10 bpm. Therefore, in the propofol-fentanyl group, sensitivity, specificity, positive predictive value, and negative predictive value were 85%, 100%, 100%, and 87% according to the conventional HR criterion, and all were 100% according to the modified HR criterion. In the propofol group, 100% efficacy was obtained based on both HR criteria. However, all patients receiving the test dose and none receiving saline developed a SBP increase > or =15 mm Hg, resulting in 100% efficacy based on the conventional SBP criterion in both groups. Our results indicate that both the modified HR criterion and the SBP criterion are clinically applicable during propofol anesthesia with or without supplemental fentanyl. IMPLICATIONS: To determine whether an epidural catheter is in a blood vessel, an epidural test dose containing 15 microg of epinephrine is used. We found that, during propofol anesthesia with or without fentanyl, a heart rate increase > or =10 bpm and a systolic blood pressure increase > or =15 mm Hg are reliable indicators for detecting accidental intravascular injection.

Adrenergic alpha-Agonists↗

PubMed1999

The effect of olprinone compared with milrinone on diaphragmatic muscle function in dogs.

UNLABELLED: We compared the effect of olprinone with milrinone on the contractility of fatigued diaphragms in dogs. Animals were divided into four groups of 10 each. In each group, diaphragmatic fatigue was induced by intermittent supramaximal bilateral electrophrenic stimulation at a frequency of 20 Hz applied for 30 min. After producing fatigue, Group I received only maintenance fluids; Group II was given a bolus injection (50 microg/kg) followed by continuous infusion (0.5 microg x kg(-1) x min(-1)) of milrinone; Group III was infused with olprinone (10 microg/kg initial dose plus 0.3 microg x kg(-1) x min(-1) maintenance dose); Group IV was infused with nicardipine (5 microg x kg(-1) x min(-1)) during olprinone administration. After the fatigue-producing period in each group, transdiaphragmatic pressure (Pdi) at low-frequency (20 Hz) stimulation decreased from the prefatigued values (P < 0.05), whereas there was no change in Pdi at high-frequency (100-Hz) stimulation. In Groups II and III, during study drug infusion, Pdi at both stimuli increased from fatigued values (P < 0.05). The increase in Pdi was larger in Group III than in Group II (P < 0.05). In Group IV, the augmentation of Pdi by olprinone was abolished in the fatigued diaphragm with an infusion of nicardipine. We conclude that olprinone is more effective than milrinone for the improvement of contractility in he fatigued diaphragm and that the potentiating mechanism of olprinone may be closely related to the transmembrane calcium movement. IMPLICATIONS: Diaphragmatic fatigue may contribute to the development of respiratory failure. Compared with milrinone, olprinone improves the contractility in fatigued diaphragm in dogs.

Animals↗

PubMed1999

Halothane minimum alveolar anesthetic concentration and neuronal nitric oxide synthase activity of the dorsal horn and the locus ceruleus in rats.

UNLABELLED: There is some evidence of a relationship between nitric oxide and pain control pathways. However, it is still controversial whether nitric oxide synthase (NOS) inhibitors affect minimum alveolar anesthetic concentration (MAC). We examined the effects of 7-nitro indazole (7-NI), a selective neuronal NOS (nNOS) inhibitor, on halothane MAC. With nicotinamide adenine dinucleotide phosphate diaphorase histochemistry, we also investigated the nNOS activity of the dorsal horn and the locus ceruleus in 26 Sprague-Dawley rats. 7-NI (100, 500, 1000 mg/kg intraperitoneally) reduced halothane MAC to 0.34% +/- 0.12%, 0.1% +/- 0.03%, and 0.05% +/- 0.12%, dose dependently (P < 0.01). 7-NI also reduced the number of nicotinamide adenine dinucleotide phosphate diaphorase-positive cells by 20% to 65% (P < 0.05 or 0.01) and the staining intensity of the axons in the locus ceruleus and lumbar and thoracic spinal cord as compared with the control group. 7-NI reduced the MAC observed with halothane anesthesia, which was accompanied by nNOS activity suppression in the spinal cord and the locus ceruleus. Our results support the hypothesis that the nitric oxide signaling pathway is related to MAC. IMPLICATIONS: We examined the effects of a selective neuronal nitric oxide synthase inhibitor, 7-nitro indazole, on halothane minimum alveolar anesthetic concentration and measured the nitric oxide synthase activity in the spinal cord and the locus ceruleus of Sprague-Dawley rats using nicotinamide adenine dinucleotide phosphate diaphorase staining method. 7-Nitro indazole decreased both the minimum alveolar anesthetic concentration and neuronal nitric oxide synthase activity.

Anesthetics, Inhalation↗

PubMed1999

Propofol decreases diaphragmatic contractility in dogs.

UNLABELLED: Volatile anesthetics depress diaphragmatic muscle function; however, no data are available regarding the effect of propofol on diaphragmatic contractility. We therefore studied this effect in dogs. Pentobarbital-anesthetized animals were divided into three groups of 10 each. Group I received only maintenance fluid; Group II was infused with a subhypnotic dose of propofol (0.1-mg/kg initial dose plus 1.5-mg x kg(-1) x h(-1) maintenance dose); Group III was infused with an anesthetic dose of propofol (0.1-mg/kg initial dose plus 6.0-mg x kg(-1) x h(-1) maintenance dose). We assessed diaphragmatic contractility by transdiaphragmatic pressure (Pdi). With an infusion of propofol in Groups II and III, Pdi at low-frequency (20-Hz) stimulation decreased from the baseline values (P < 0.05), whereas Pdi at high-frequency (100-Hz) stimulation did not change. Compared with Group I, Pdi at 20-Hz stimulation decreased during propofol administration in Groups II and III (P < 0.05). The decrease in Pdi was more in Group III than in Group II (P < 0.05). We conclude that propofol is associated with a dose-related inhibitory effect on diaphragmatic contractility in dogs. IMPLICATIONS: Propofol is an effective IV anesthetic for the induction and maintenance of anesthesia. Subhypnotic and anesthetic doses of propofol decrease diaphragmatic contractility in dogs.

Anesthetics, Intravenous↗

PubMed1999

Protection from diaphragmatic fatigue by nitric oxide synthase inhibitor in dogs.

The role of endogenous nitric oxide (NO) in producing diaphragmatic fatigue was examined in 26 anaesthetized, mechanically ventilated dogs divided into four groups. In Group Ia (n = 5), dogs without fatigue received only Ringer's lactate solution. In Group Ib (n = 5), dogs without fatigue were given i.v. L-arginine analog N omega-nitro-L-arginine methyl ester (L-NAME) 10 mg.kg-1 to inhibit NO synthase (NOS). Groups IIa and IIb (n = 8 of each) received the same doses of i.v. lactate and L-NAME as Groups Ia and Ib effectively. Following administration of the i.v. solution, diaphragmatic fatigue was induced by intermittent supramaximal bilateral electrophrenic stimulation at a frequency of 20 Hz applied for 30 min. Diaphragmatic contractility was assessed in each group by measuring transdiaphragmatic pressure (Pdi). No difference in Pdi was observed between Groups Ia and Ib. After the fatigue-producing period, in Group IIa, Pdi at low-frequency (20 Hz) stimulation decreased from the pre-fatigued values (P < 0.05), whereas Pdi at high-frequency (100 Hz) stimulation did not change. In Group IIb, given L-NAME before producing fatigue, Pdi at both stimuli did not change. In conclusion, L-NAME inhibits the production of diaphragmatic fatigue. This finding suggests that endogenous NO plays an important role in producing diaphragmatic fatigue.

Animals↗

PubMed1999

Blood flow velocity in the middle cerebral artery response to tourniquet release.

This study was undertaken to examine the effects of tourniquet release on middle cerebral arterial (MCA) blood flow velocity in patients undergoing general anaesthesia for orthopaedic surgery. In 30 patients (ASA physical status 1 or 2) undergoing orthopaedic procedures on the upper (Group U, n = 15) and lower (Group L, n = 15) extremities, MCA blood flow velocity was measured before and after tourniquet deflation using transcranial Doppler sonography. The MCA blood flow velocity increased after release of the intraoperative tourniquet and remained elevated for two minutes in Group U (P < 0.05) and for four minutes in Group L (P < 0.05). The increase in MCA blood flow velocity was greater in Group L than in Group U (P < 0.05). A positive linear correlation between MCA blood flow velocity and PETCO2 after tourniquet deflation was observed in both groups (P < 0.001).

Adult↗

PubMed1999

[Ketamine infusion therapy for refractory neuralgia in spinal disease: report of two cases].

We report two cases of refractory pain in a spinal disease. One case was a 60-year-old male who presented intractable pain in bilateral upper extremities after anterior fusion (C5/6, 6/7) for cervical spondylosis. The other was a 63-year-old female who also had intractable pain in the left anterio-lateral chest wall with no remarkable past history. Both cases were refractory to nonsteroidal anti-inflammatory drugs (NSAIDs) or minor tranquilizer or local anesthesia with bupivacaine. However, their pain was significantly relieved by the intravenous administration of a test dose (5mg) of ketamine which is a noncompetitive blocker of N-methyl-D-aspartate (NMDA) receptors. As for case 1, the effect of the injection of the test dose lasted, so continuing infusion therapy of ketamine was cancelled. In case 2, recurrence of the pain was recognized gradually. She underwent continuing infusion therapy of 2mg/kg of ketamine, and it brought about continued pain relief. We conclude that ketamine infusion therapy should also be considered for therapy of refractory neuralgia in spinal disease.

Analgesics↗

PubMed1999

[Epidural anesthesia for cesarean section in a patient with dilated cardiomyopathy (DCM)].

A 23-year-old patient with dilated cardio myopathy (DCM) was scheduled for a cesarean section. We inserted an epidural catheter at the L 2/3 interspace and injected 1.5% lidocaine 6 ml with epinephrine 30 micro g and fentanyl 50 micro g. The analgesic level 15 minutes after injection was achieved up to the eighth thoracic dermatome. Dopamin 5 micro g.kg-1.min-1 was infused simultaneously. Analgesia was sufficient for the surgery, and heart rate and blood pressure were stable throughout the operation. The infant's apgar scores were 9 and 10. Epidural anesthesia is one of the options for cesarean section in pregnant women with DCM.

Adult↗

PubMed1998

Thoracic epidural block attenuates cardiovascular response to apnea in rabbits.

PURPOSE: Apnea is one of the potential complications during anaesthesia. If sympathetic nerve activity is blocked by epidural anaesthesia, circulatory responses to apnea might change. Our objective was to assess the potential modifying effects of epidural anaesthesia on the cardiovascular responses to apnea in the animals. METHODS: Twenty rabbits anaesthetised with pentobarbital (25 mg.kg-1 i.v., 8 mg.kg-1.hr-1) and pacuronium bromide (0.2 mg.kg-1.hr-1 i.v.) were randomly assigned to one of two groups: control (n = 10) and epidural (n = 10). In the control group, 0.6 ml saline, and in the epidural group, 0.6 ml lidocaine 1% was injected into the epidural space respectively. After mechanical ventilation with FIO2 0.4, apnea was induced by disconnecting the anaesthetic circuit from the endotracheal tube, and mean arterial pressure (MAP), heart rate (HR), and time to cardiac arrest were measured. RESULTS: Before apnea MAP was lower in the epidural than in the control group (73 +/- 10 vs 91 +/- 10 mmHg, P < 0.05). Heart rate was not different between groups (264 +/- 36 vs 266 +/- 24 bpm). Mean arterial pressure increased in the control group after apnea, but not in the epidural group. The time to cardiac arrest was less in the epidural group than in the control group (420 +/- 67 vs 520 +/- 61 sec, P < 0.05). Heart rate decreased markedly after apnea in the control group whereas it decreased gradually in the epidural group. CONCLUSION: Thoracic epidural anaesthesia attenuated cardiovascular response to apnea and reduced the time to cardiac arrest.

Anesthesia, Epidural↗

PubMed1998

Calcium channel blockers attenuate cardiovascular responses to tracheal extubation in hypertensive patients.

PURPOSE: Hypertensive patients exhibit exaggerated cardiovascular responses to tracheal extubation. This study was undertaken to examine the inhibitory effects of calcium channel blockers, nicardipine and diltiazem, on haemodynamic changes after tracheal extubation. METHODS: Sixty hypertensive patients (ASA physical status II) undergoing elective orthopaedic (upper and lower extremity) surgery received, in a randomized, double-blind manner, 30 micrograms.kg-1 nicardipine, 0.2 mg.kg-1 diltiazem or saline (as a control) (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: The HR, MAP and RPP increased after tracheal extubation in the control group (P < 0.05). The increases in these haemodynamic variables were attenuated with nicardipine or diltiazem. The inhibitory effects of diltiazem on these cardiovascular responses to tracheal extubation were greater than those of nicardipine (HR; 86 +/- 7 vs 101 +/- 10, RPP; 11,437 +/- 1,575 vs 14,675 +/- 2,874, mean +/- SD, P < 0.05). CONCLUSION: Compared with nicardipine, administration of diltiazem produced greater attenuating the circulatory responses to tracheal extubation in hypertensive patients.

Adult↗

PubMed1998

Diltiazem-lidocaine combination for the attenuation of cardiovascular responses to tracheal intubation in hypertensive patients.

PURPOSE: Hypertensive patients are prone to haemodynamic changes after laryngoscopy and tracheal intubation. This study was undertaken to compare the efficacy of a combination of diltiazem and lidocaine with that of each drug alone for suppressing the cardiovascular responses to tracheal intubation. METHODS: Sixty hypertensive patients (ASA II), defined as systolic blood pressure > 160 mmHg and/or diastolic blood pressure > 95 mmHg (World Health Organization), undergoing elective surgery received, in a randomized, double-blind manner, 0.3 mg.kg-1 diltiazem, 1.5 mg.kg-1 lidocaine, or 0.3 mg.kg-1 diltiazem plus 1.5 mg.kg-1 lidocaine i.v. (n = 20 of each) before the initiation of laryngoscopy. Anaesthesia was induced with 5 mg.kg-1 thiopentone i.v., and tracheal intubation was facilitated with 2 mg.kg-1 succinylcholine i.v. after precurarization with 0.02 mg.kg-1 vecuronium i.v. Changes in heart rate (HR), mean arterial pressure (MAP) and rate-pressure product (RPP) were measured before and at immediate, 1, 2, 3, 5 and 10 min after tracheal intubation. RESULTS: The inhibitory effects of diltiazem-lidocaine combination on cardiovascular responses to tracheal intubation was greater than those of diltiazem or lidocaine as a sole medicine (RPP; 10,602 +/- 1448 (combination) vs 11,787 +/- 1345 (diltiazem), 15,428 +/- 1756 (lidocaine), mean +/- SD, P < 0.05). CONCLUSION: Prophylactic therapy with diltiazem-lidocaine combination is more effective than diltiazem or lidocaine alone for attenuating the cardiovascular changes associated with tracheal intubation in hypertensive patients.

Aged↗

PubMed1998

Prophylactic antiemetic therapy with granisetron-droperidol combination in patients undergoing laparoscopic cholecystectomy.

PURPOSE: A relatively high incidence of postoperative nausea and vomiting (PONV) occurs in patients undergoing laparoscopic cholecystectomy. This study was undertaken to compare the efficacy of granisetron-droperidol combination with each drug alone for the prevention of PONV after laparoscopic cholecystectomy. METHODS: In a randomized, double-blind manner, 150 female inpatients received 3 mg granisetron (Group G), 1.25 mg droperidol (Group D) or 3 mg granisetron plus 1.25 mg droperidol (Group GD)(n = 50 for each) i.v. immediately before the induction of anaesthesia. The same standard general anaesthetic technique, which consisted of isoflurane and nitrous oxide in oxygen, was used. Nausea, vomiting and safety assessments were performed continuously during the first 24 hr after anaesthesia. RESULTS: Complete response, defined as no PONV and no administration of rescue antiemetic medication, was 86% in Group G, 64% in Group D and 98% in Group GD (P = 0.03 vs Group G, P = 0.001 vs Group D). No clinically adverse events were observed in any group. CONCLUSION: Granisetron-droperidol combination is more effective than each antiemetic alone in the prevention of PONV after laparoscopic cholecystectomy.

Adult↗

PubMed1998

Prevention of PONV with granisetron, droperidol or metoclopramide in patients with postoperative emesis.

PURPOSE: A high incidence of postoperative nausea and vomiting (PONV) has been noted in patients with a history of postoperative emesis. This study was undertaken to compare the efficacy of granisetron, droperidol and metoclopramide, in the prevention of PONV in such patients undergoing general anaesthesia for major gynaecological surgery. METHODS: In a randomised, double-blind study, 90 female patients received 2.5 mg granisetron, 1.25 mg droperidol or 10 mg metoclopramide (n = 30 of each) i.v. immediately before induction of anaesthesia. The same standard general anaesthetic technique, which consisted of isoflurane in nitrous oxide and oxygen, was used. Nausea, vomiting and safety assessments were performed continuously during the first 24 hr after anaesthesia. RESULTS: The incidence of PONV was 20% with granisetron, 57% with droperidol and 60% with metoclopramide (P < 0.05; overall Fisher's exact probability test). No clinically adverse events were observed in any group. CONCLUSION: Granisetron is more effective than droperidol or metoclopramide in preventing PONV in female patients with a history of postoperative emesis.

Adult↗

PubMed1998

Cardiovascular responses to tracheal extubation or LMA removal in children.

PURPOSE: This study was designed to investigate the cardiovascular effects related to tracheal extubation or laryngeal mask airway (LMA) removal in children. METHODS: Sixty children, ASA physical status 1, 4-10 yr of age, undergoing minor elective surgery (inguinal hernia and phimosis) were allocated randomly to have their surgery performed with endotracheal intubation (Group ET, n = 30) or LMA (Group LMA, n = 30) and were studied for cardiovascular responses related to extubation or LMA removal. Changes in heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured before and 1, 2, 3, 5, and 10 min after tracheal extubation or LMA removal when the patients were awake. RESULTS: The maximal changes in HR, SBP and DBP were less in Group LMA than in Group ET during the observation period (HR; 12 vs 26, SBP; 14 vs 28, DBP; 9 vs 13, median, P < 0.05). CONCLUSION: Laryngeal mask airway removal elicited less haemodynamic change than tracheal extubation in paediatric patients.

Blood Pressure↗

PubMed1998

Anaesthetic induction time for tracheal intubation using sevoflurane or halothane in children.

The current study was designed to determine the anaesthetic induction time required for tracheal intubation (TimeEI) with equipotent inspired concentrations of 5% sevoflurane and 2.5% halothane in oxygen. TimeEI that prevents 50% and 95% of patients from coughing and gross purposeful muscular movements after intubation was defined as TimeEI50 and TimeEI95, respectively. Thirty-six patients aged 1-7 years were enrolled in the study. Anaesthesia was induced via mask and when TimeEI attained a predetermined value, intubation was performed using an uncuffed tube. Each TimeEI at which tracheal intubation was attempted was predetermined according to the up-and-down method. When intubation was accomplished without gross purposeful muscular movements, it was considered a smooth intubation. Determination with this method revealed that TimeEI50 and TimeEI95 for the sevoflurane/halothane groups were 147/214 s and 194/255 s, respectively. In conclusion, it is possible to determine TimeEI using an inspired sevoflurane concentration of 5% and halothane 2.5% in oxygen. The technique with 5% sevoflurane seems more practical for paediatric anaesthesia induction in busy clinical situations.

Anesthetics, Inhalation↗