PubMed Health⌕ Search

Biomedical subjects

K Kitaguchi

Publications and source records attributed to K Kitaguchi.

At least 19 recordsLinked to original sources
PubMed2004

Double lumen tube location predicts tube malposition and hypoxaemia during one lung ventilation.

BACKGROUND: Poor positioning of an endobronchial double lumen tube (DLT) could affect oxygenation during one lung ventilation (OLV). We set out to relate DLT position to hypoxaemia and DLT misplacement during OLV. METHODS: We recruited 152 ASA physical status I-II patients about to have elective thoracic surgery. The trachea was intubated with a left-sided DLT. Tube position was assessed by fibre-optic scope and correction was made after patient positioning and during OLV. If Pa(O(2)) was less than 10.7 kPa, the DLT position was checked and then PEEP, continuous positive airway pressure (CPAP), oxygen insufflation, or two lung ventilation (TLV) were tried. RESULTS: The DLT was found to be misplaced in 49 patients (32%) after patient positioning, and in 38 patients (25%) during OLV. PEEP to the dependent lung, CPAP or apneic oxygen insufflation to the non-dependent lung, or brief periods of TLV, were applied in 46 patients (30%). Patients who had DLT malposition after placing the patient in the lateral position had a greater incidence of DLT malposition during OLV (59 vs 9%) and also required each intervention more frequently (57 vs 10%). Patients with DLT malposition during OLV also required interventions more often (84 vs 12%). CONCLUSIONS: Patients who have DLT malposition after placing the patient in the lateral position had more DLT malposition during OLV and hypoxaemia during OLV.

Adult↗
PubMed2004

Inclusion of epinephrine to hyperbaric tetracaine and the supine position enhance the cephalad spread of spinal anaesthesia compared with hyperbaric teracaine alone in the lithotomy position.

BACKGROUND: Intrathecal epinephrine can produce prolongation of duration of spinal anaesthesia by reducing vascular absorption of the local anaesthetics. The patient's positioning can change the cephalad spread of hyperbaric local anaesthetics by affecting the lordosis of the vertebral canal. These factors combined are expected to affect the cephalad spread of sensory block levels. The purpose of this study was to investigate whether combined use of epinephrine with hyperbaric tetracaine in the supine position can enhance the cephalad spread of sensory block levels compared with hyperbaric tetracaine alone in the lithotomy position. METHODS: ASA physical status I or II 48 urological (lithotomy group) and 48 orthopaedic patients (supine group) scheduled to undergo elective surgical procedures in the lithotomy or supine position under spinal anaesthesia were enrolled. Patients in each group were randomly divided into two subgroups to receive intrathecal 10 mg of hyperbaric tetracaine with or without 0.2 mg of epinephrine (Groups L, LE, S, and SE). The extent of sensory blockade was assessed by loss of cold sensation. After achievement of sensory blockade up to T10, the patients in Groups L and LE were immediately placed in the lithotomy position. Patients in Groups S and SE were maintained in the supine position. RESULTS: The highest sensory blockade in the SE Group was on average statistically significantly higher than in the L Group. The mean time taken to the highest sensory blockade in the SE Group was statistically significantly longer than in Groups L and S. Atropine for bradycardia was used more frequently in the SE Group than in the other groups. CONCLUSIONS: Combined use of epinephrine with hyperbaric tetracaine in the supine position can enhance the cephalad spread of sensory block levels compared with hyperbaric tetracaine alone in the lithotomy position.

Aged↗
PubMed2003

Plasma propofol concentration and EEG burst suppression ratio during normothermic cardiopulmonary bypass.

BACKGROUND: During cardiopulmonary bypass (CPB), several factors affect drug disposition and action. This topic has not been studied extensively during normothermic CPB. In this study, we related propofol dose to plasma propofol concentration and burst suppression of the EEG during normothermic bypass. METHODS: After institutional approval and informed consent, 45 patients having cardiac surgery were assigned randomly to receive propofol infusions at 4 (Group A), 5 (Group B) and 6 (Group C) mg kg(-1) h(-1) during normothermic CPB. In all patients, small to moderate doses of fentanyl were also administered. Plasma propofol concentration and burst suppression ratio (BSR) were measured at the following times: (1) 10 min before CPB, (2) 10 min after the start of CPB, (3) 30 min after the start of the CPB, (4) just after aortic declamping, and (5) 60 min after CPB. RESULTS: At baseline, plasma propofol concentrations were similar among the three groups. After the start of CPB, the concentrations of propofol decreased significantly by 41, 35, and 30% of control values in Groups A, B, and C, respectively. In Group A, the concentration of propofol during CPB remained unchanged at less than the concentration before bypass. In Groups B and C, plasma propofol concentrations gradually increased during CPB to the pre-bypass concentrations. In Group A, BSR values did not change significantly during CPB. In Groups B and C, BSR values gradually increased and became significantly greater than baseline values. No patient reported intraoperative awareness. CONCLUSION: The pharmacokinetics and pharmacodynamics of propofol change during normothermic CPB. During normothermic CPB, the efficacy of propofol may be enhanced compared with before CPB.

Adult↗
PubMed2003

Comparison of the effects of sevoflurane and propofol on cooling and rewarming during deliberate mild hypothermia for neurosurgery.

BACKGROUND: Because the time available for cooling and rewarming during deliberate mild hypothermia is limited, studies of the rate of the cooling and rewarming are useful. The decrease in core hypothermia caused by heat redistribution depends on the anaesthetic agent used. We therefore investigated possible differences between sevoflurane and propofol on the decrease and recovery of core temperature during deliberate mild hypothermia for neurosurgery. METHODS: After institutional approval and informed consent, 26 patients were assigned randomly to maintenance of anaesthesia with propofol or sevoflurane. Patients in the propofol group (n=13) received propofol induction followed by a continuous infusion of propofol 3-5 mg kg(-1) h(-1). Patients in the sevoflurane group (n=13) received propofol induction followed by sevoflurane 1-2%. Nitrous oxide and fentanyl were also used for anaesthetic maintenance. After induction of anaesthesia, patients were cooled and tympanic membrane temperature was maintained at 34.5 degrees C. After surgery, patients were actively rewarmed. RESULTS: There was no difference in the rate of decrease and recovery of core temperature between the groups. There was also no difference in skin surface temperature gradient (forearm to fingertip), heart rate and mean arterial blood pressure between the groups. CONCLUSIONS: Sevoflurane-based anaesthesia did not affect cooling and rewarming for deliberate mild hypothermia compared with propofol-based anaesthesia.

Adult↗
PubMed2002

Long-term retention of motor skill in macaque monkeys and humans.

Remarkable human performance, such as playing the violin, is often based on motor skills that, once acquired, are retained for a long time. To examine how motor skills are retained, we trained monkeys and humans extensively to perform many visuomotor sequences and examined their performance after a long retention period of up to 18 months. For both monkeys and humans, we found strong evidence for long-term retention of motor skills. Each of the monkey subjects initially learned 6-18 sequences of button presses extensively by trial-and-error for up to 18 months. After a long retention period, they were asked to perform the previously learned (OLD) sequences together with completely new (NEW) sequences. The performance for OLD sequences was much better than for NEW sequences in terms of accuracy (assessed by the number of errors to criterion) and speed (assessed by the performance time). However, the retention was interfered with in two conditions, but in selective manners: (1) Learning of other sequences during the retention period interfered with accuracy, but not speed, of performance; (2) Inter-manual transfer was absent for speed, but not accuracy, of performance. The human subjects performed basically the same task as the monkeys. Each subject initially learned one sequence of 20 button presses by trial-and-error during an 8-10 day learning session. After 16 months, they were asked to perform the previously learned sequence (OLD sequence) and additional sequences including RECENT sequences (learned one day before) and NEW sequences. Their performance was considerably better on OLD and RECENT sequences than NEW sequences. Whereas the number of errors (reflecting 'accuracy') was lower for RECENT than for OLD sequences, the performance time (reflecting 'speed') was shorter for OLD than for RECENT sequences. Interestingly, the subjects were unaware that they had experienced OLD sequences. The results suggest that a motor skill is acquired and retained in two different forms, accuracy and speed. This occurs separately but concurrently. This conclusion is consistent with the hypothesis that at least two neural mechanisms operate independently to represent a motor skill.

Adult↗
PubMed2001

The association of high jugular bulb venous oxygen saturation with cognitive decline after hypothermic cardiopulmonary bypass.

UNLABELLED: This study was conducted to investigate whether jugular bulb venous oxygen saturation (SjVO(2)) predicted cognitive decline after cardiac surgery with hypothermic cardiopulmonary bypass (CPB). We studied 35 patients undergoing cardiac surgery. After the induction of anesthesia, a 5.5F fiberoptic oximetry catheter was retrogradely inserted into the jugular bulb, and SjVO(2) and other cerebral oxygenation variables were analyzed before, during, and after CPB. At each point, an oxyhemoglobin dissociation curve was drawn, and the P(50) value of jugular bulb venous blood was calculated by computer analysis. Cognitive function was assessed with the revised version of Hasegawa's Dementia Scale and the Benton Revised Visual Retention Test before and early after the operation. In 15 patients (the Decline group), cognitive function was declined after surgery, whereas it remained unchanged in 20 patients (the Normal group). SjVO(2) was significantly higher and cerebral oxygen extraction was significantly lower before and during CPB in the Decline group than in the Normal group (P < 0.05). The oxygen pressure at an oxygen saturation of 50% was significantly lower before and after CPB in the Decline group than in the Normal group (P < 0.05). Logistic regression analysis showed that high SjVO(2) was a predictor of cognitive decline after cardiac surgery. We conclude that high SjVO(2) was associated with cognitive decline after cardiac surgery with hypothermic CPB. IMPLICATIONS: Jugular bulb venous oxygen desaturation has been suggested as a predictor of cognitive decline after cardiac surgery. However, the clinical value of jugular bulb venous oxygen saturation (SjVO(2)) may be limited during hypothermic cardiopulmonary bypass (CPB) when oxygen affinity to hemoglobin is increased. This study shows that high SjVO(2) before and during hypothermic CPB is a predictor of subsequent cognitive decline.

Adult↗
PubMed2001

Effect of mild hypothermia on nicorandil-induced vasodilation of pial arterioles in cats.

OBJECTIVE: Nicorandil is characterized as hybrid between nitrates and potassium channel activators. Recent evidence suggested that mild hypothermia may alter cerebral vasodilation induced by a nitrate agent and potassium channel opener. However, the effect of mild hypothermia on nicorandil-induced vasodilation is not known. The present study was conducted to investigate whether mild hypothermia could alter nicorandil-induced cerebral vasodilation. In addition, the effects of mild hypothermia on cerebral vasodilation induced by nitroglycerin, a nitrate agent, and cromakalim, a selective adenosine 5'-triphosphate-sensitive potassium channel opener, were assessed in the same model. DESIGN: Prospective, randomized, experimental study with repeated measures. SETTING: Investigational animal laboratory. SUBJECTS: Twenty-four cats. INTERVENTIONS: Animals were anesthetized with pentobarbital. The cranial window technique, combined with microscopic video recording, was used to measure small (50-100 microm) and large (100-200 microm) pial arteriolar diameter in an experiment. Animals were assigned randomly to either a normothermic (37 degrees C) or a hypothermic (33 degrees C) group. Nicorandil, nitroglycerin, or cromakalim at concentrations of 10(-8), 10(-6), or 10(-4) mol/L was applied topically in the cranial window, and the diameter of pial arterioles was measured. MEASUREMENTS AND MAIN RESULTS: Topical administration of nicorandil, nitroglycerin, and cromakalim significantly dilated both small and large pial arterioles in a dose-dependent manner during normothermia. Nicorandil-induced vasodilation of either large or small pial arterioles was not affected by hypothermia. However, hypothermia significantly attenuated nitroglycerine-induced vasodilation in both large and small pial arterioles and enhanced cromakalim-induced vasodilation in both large and small pial arterioles. CONCLUSIONS: Nicorandil-induced vasodilation of cerebral pial arterioles was not affected by mild hypothermia. By contrast, mild hypothermia significantly attenuated nitroglycerin-induced vasodilation and enhanced cromakalim-induced vasodilation.

Administration, Topical↗
PubMed2001

[Effect of colforsin daropate hydrochloride after cardiopulmonary bypass].

We evaluated the effects of colforsin daropate hydrochloride (CDH) after cardiopulmonary bypass (CPB) in comparison with milrinone. CDH or milrinone were given during and after CPB combined with cathecholamines so as to maintain mean arterial pressure (mABP > 60 mmHg) and cardiac index (CI > 3.0 l.min-1.m-2). Hemodynamics measurement was done immediately after CPB (A 1), one hour after CPB (A 2) and after the chest closure (A 3). In CDH group, mABP was significantly higher compared with milrinone group. Also, CDH group showed a significant reduction in the cases of combined use of dobutamine (at A 2, A 3) and norepinephrine (at A 1, A 2) compared with milrinone group. In conclusion, colforsin daropate hydrochloride exerts more inotropic effect and could reduce the necessity of combined use of cathecholamine compared with milrinone.

Aged↗
PubMed2001

[Assessment of anesthesia satisfaction using direct interviews at post-anesthesia clinic].

The authors studied 5,034 consecutive patients undergoing elective surgery. Preoperative, intraoperative, and postoperative variables were gathered and patient satisfaction was assessed using direct interviews at pre- and post-anesthesia clinic. Fifty-nine percent of the 4,717 responders showed satisfaction and 4% showed dissatisfaction with anesthesia. The most undesirable perioperative outcome was vomiting/nausea. Other undesirable outcomes include discomfort of urine catheter, sore throat, memory of extubation, postoperative pain and so on. Anesthesiologist can improve the quality of anesthesia by preoperative explanation and preventative management for undesirable perioperative outcomes.

Anesthesia↗
PubMed2001

[Anesthetic management of the King-Denborough syndrome].

The King-Denborough syndrome (KDS) is a congenital myopathy with musculoskeletal abnormalities, and definitely associated with susceptibility to malignant hyperthermia (MH). We present the first report in Japan concerning the management of a KDS patient. A 2-year-old boy was scheduled for cryptorchidopexy. He had some physical signs of KDS, e.g. pectus excavatum, low-set ears, malar hypoplasia, micrognathia, ptosis and down-slanting palpebral fissures. Moreover, his mother and maternal grand-uncle had medical history of MH. Therefore, he was diagnosed as KDS by pediatricians. All of the preoperative examinations, including serum creatine phosphokinase level, are normal. Previous 15 case-reports suggest that in KDS patients MH might be triggered by volatile anesthetics. To avoid the trigger, we maintained the general anesthesia with propofol, fentanyl and vecuronium. During perioperative period, his body temperature was 36.3-38.1 degrees C, and no symptom of MH was observed. It is rare that a diagnosis of KDS is made preoperatively since the MH-induction is involved in the criteria of this syndrome. In the anesthesia of patients who are suspected of KDS from their characteristic features or familial histories, an anesthesiologist should pay attention to prevent MH. The total intravenous anesthesia method appears useful for the management of KDS.

Abnormalities, Multiple↗
PubMed2001

[Ketamine lollipop for pediatric premedication].

Lollipop containing ketamine (50 mg) was evaluated for the premedication of pediatric patients. The subject of this study were 12 children aged from 1 year 7 months to 6 years. They received the lollipop and showed relatively good emotional state and no typical side effects. These results suggest good possibility of ketamine lollipop as the premedication for pediatric patients.

Administration, Oral↗
PubMed2001

[Propofol Concentration during Maintenance of and Emergence from Propofol/Epidural Anesthesia: Comparison between Younger and Elderly Patient].

To investigate the influence of patient age on the sensitivity to propofol, we measured blood propofol concentrations in ten elderly (over 70 years of age) and ten younger (under 60 years of age) patients undergoing elective abdominal surgery during propofol/epidural anesthesia. Bispectral index (BIS) was continuously recorded for monitoring anesthetic effect, and the infusion rate of propofol was controlled to keep BIS at 50 after the induction of anesthesia with propofol. At steady-state before skin incision, propofol concentrations to maintain BIS at 50 in younger and elderly patients were 4.3 +/- 1.6 micrograms.ml-1 and 3.2 +/- 1.3 micrograms.ml-1, respectively, and there was no significant difference. Mean blood propofol concentrations were 4.0 +/- 1.5 micrograms.ml-1 for the younger group and 3.2 +/- 1.7 micrograms.ml-1 for the elderly group at the end of surgery immediately before discontinuation of propofol, and they were 1.9 +/- 0.7 micrograms.ml-1 (BIS = 86 +/- 7) for the younger group and 1.5 +/- 0.8 micrograms.ml-1 (BIS = 84 +/- 3) for the elderly group at the time of eye opening with no significant difference. We found appreciable individual variations in the propofol concentrations both in younger and elderly patients in this study.

Abdomen↗
PubMed2001

[Relationship between minimum alveolar concentration and electroencephalographic bispectral index as well as spectral edge frequency 95 during isoflurane/epidural or sevoflurane/epidural anesthesia].

To investigate the relationship between minimum alveolar concentration (MAC) and electroencephalographic variables, we measured the bispectral index (BIS) and the spectral edge frequency 95 (SEF 95) in 17 patients undergoing elective surgery during isoflurane/epidural (n = 8) or sevoflurane/epidural (n = 9) anesthesia. Patients received 2.0 MAC end-tidal concentrations of isoflurane or sevoflurane, and the BIS and the SEF 95 were recorded after 15 min of an unchanged end-tidal concentration. The concentration of the inhalational agent was decreased to 1.2 MAC, and measurements were repeated again. During isoflurane anesthesia, the BIS increased significantly (3.6 +/- 3.9 at 2.0 MAC, 43.5 +/- 9.2 at 1.2 MAC [mean +/- SD]). In contrast, the BIS did not change significantly during sevoflurane anesthesia (35.3 +/- 8.4 at 2.0 MAC, 42.8 +/- 6.1 at 1.2 MAC). There were significant differences in the BIS and the SEF 95 at 2.0 MAC between isoflurane and sevoflurane groups. In contrast, the BIS and the SEF 95 showed no difference at 1.2 MAC between the groups. These findings suggest that different inhalational anesthetics may have different effects on the BIS and the SEF 95.

Adult↗
PubMed2001

[The memory of tracheal extubation during emergence from general anesthesia].

The authors evaluated the memory of tracheal extubation during emergence from general anesthesia. We screened 3,039 consecutive patients undergoing elective surgery from November 1, 1998 to December 31, 1999. Of 3,039 patients, 1,993 were interviewed postoperatively at the anesthesia clinic and 202 had the memory of tracheal extubation. The incidence was higher in the groups of female, younger and propofol anesthesia compared to male, elder and inhalational anesthesia, respectively. The patients who were dissatisfied with anesthesia were more in the patients with the memory of tracheal extubation compared to the patients without the memory. We consider that the memory of tracheal extubation contributes to the dissatisfaction with anesthesia.

Adolescent↗
PubMed2001

[Intraoperative unilateral changes in myogenic motor evoked potentials in patients undergoing thoracic aortic surgery].

Motor evoked potentials (MEPs) can be employed for monitoring the functional integrity of the descending motor pathways during thoracic aortic surgery. Since MEPs can be affected by a variety of intraoperative factors, intraoperative MEP changes have to be carefully interpreted. In this report, we describe two patients undergoing thoracic aortic surgery, in whom MEPs from the unilateral lower limb disappeared after femoral artery cannulation, and MEPs' recovered by modifying the position or removing the cannula. MEPs in the contralateral side remained unchanged. Neither patients showed postoperative neurologic dysfunction in the lower limbs. These observations suggest that regional ischemia of the lower limbs caused by femoral artery cannulation can affect intraoperative MEP finding.

Aorta, Thoracic↗
PubMed2001

[A case of awareness during propofol anesthesia using bispectral index as an indicator of hypnotic effect].

A 77-year old, woman weighing 44 kg with mild liver dysfunction underwent lower abdominal surgery. Anesthesia was induced with propofol 60 mg and fentanyl 0.1 mg. Tracheal intubation was facilitated with vecuronium 8 mg, and the lungs were ventilated with 33% oxygen in air. The bispectral index (BIS) was continuously monitored. Anesthesia was maintained with propofol infusion and analgesia was provided by thoracic epidural infusion of lidocaine 1.5%. The infusion rate of propofol was altered to maintain the BIS value between 40 and 50. The patient was hemodynamically stable with propofol 1.5 mg.kg-1.hr-1 and the BIS value was maintained about 40 during the operation. Near the end of the operation the patient moved suddenly. Suspecting inadequate anesthesia, a total of 40 mg of propofol i.v. and 5 ml of the epidural infusion were given. Immediately before the movement the BIS value was about 40. The operation was completed 30 min later. On discharge from the operating room the patient declared that she had been awake. She had heard voices and felt the surgeon working, but had suffered no pain. The BIS is a useful indicator for hypnotic effect, but this case demonstrates that awareness might occur even when BIS value indicates adequate hypnotic state.

Aged↗
PubMed2000

Characteristics of sequential movements during early learning period in monkeys.

We previously demonstrated that the organization of a learned sequential movement, after long-term practice, is based on the entire sequence and that the information pertaining to the sequence is largely specific to the hand used for practice. However, it remained unknown whether these characteristics are present from the beginning of learning. To answer the question, we examined the performance of four monkeys for the same sequential procedure in the early stage of learning. The monkeys' task was to press five consecutive pairs of buttons (which were illuminated), in a correct order for every pair, which they had to find by trial-and-error during a block of trials. We first examined whether the memory of a sequential procedure that was learned once was specific to the hand used for practice. The second time that the monkeys attempted to learn a novel sequence, they were required to use either the same hand they used the first time or the opposite hand. The number of errors decreased to a similar degree in the same-hand condition and in the opposite-hand condition. The performance time decreased in the same-hand condition, but not in the opposite-hand condition. The results suggest that, in the early stage of learning, memory of the correct performance of a sequential procedure is not specific to the hand originally used to perform the sequence (unlike the well-learned stage, where the transfer was incomplete), whereas memory of the fast performance of a sequential procedure is relatively specific to the hand used for practice (like the well-learned stage). We then examined whether memory of a sequential procedure depends on the entire sequence, not individual stimulus sets. For the second learning block, we had the monkey learn the sequence in the same or reversed order. In the reversed order, the order within each set was identical, but the order of sets was reversed. The number of errors decreased in both the same-order and reversed-order conditions to a similar degree for two out of four monkeys; the decrease was larger in the same-order condition for the other two monkeys. For all monkeys, the performance time decreased in the same-order condition, but not in the reversed-order condition. The results suggest that the memory structure for correct performance varies among monkeys in the early stage of learning (unlike the well-learned stage, where the memory of individual sets was consistently absent). On the other hand, memory of the fast performance of a sequential procedure is relatively specific to the learned order used for practice (like the well-learned stage).

Animals↗