석탄계용융환원 Fe-Cr 제조법

이일옥,조종민 대한금속재료학회(대한금속학회) 1987 대한금속·재료학회지 Vol.25 No.7

척수 손상시 Fentanyl, Halothane 마취에 의한 뇌 체성 감각 유발 전위 변화에 관한 연구

이일옥,최영석 대한마취과학회 1992 Korean Journal of Anesthesiology Vol.25 No.6

Spinal cord injury may occur during surgical correction of spinal deformity. In this situations, administrations of opiate receptor antagonists have known to improve spinal cord damage. Although those therapeutic modalities for the management of acute trauma of the spinal cord, impsoved the mean systemic arterial pressure controversy continues regarding their effectiveness Because opioids or inhalational anesthetics are used clinically, the effect of an opiate antagonist was evaluated by cortical somatosensory evoked potentials(cortical SEPs) which occur in 24 cats undergoing compressive injury on the posterior spinal cord during fentanyl or halothane anesthesia. Anesthesia was induced with pentobarbiturate(50 mg/kg, im). A balloon tipped catheter was inserted in the epidural space with tip located at thoracolumbar Junction. Spinal cord compressive injury was produced by balloon inflation for 20 minutes during intravenous saline infusion (control group), fentanyl(group l) or halothane(group 2) anesthesia Naloxone(5mg/kg) was administered intravenously following injury to all animals. Cortical SRPs were determined before and after induction of anesthesia, during the spinal cord compressive injury for 5 minutes, 10 minutes, l5 minutes, 20 minutes, after naloxone administration, and after removal of compressive injury. General anesthesia resulted in increases of latency and reductions of amplitude in the cortical SEPs. The reductions of amplitude were more marked than increases of latency in group 1, 2. During the cord injury, group 1 resulted in more reductions of amylitude than the other groups. But there were no significant differences among the groups. The administration of naloxone far improved latencies and amplitudes in the cortical SEPs of group 1 more than in other two groups. But there were no significant differences among the groups. Less recovery of the cortical SRPs response to naloxone in control group than the other groups. These results do nat support the supposition that opioid anesthesia produces an adverse effect upon cortical SEPs following spinal cord compressive injury and treatment with naloxone in the dose used in this study improves neurologic recovery of cortical SEPs less significantly

노인의 수술전 자율기능 검사는 기관내 삽관시 정주한 Labetalol 의 심혈관계에 대한 효과를 예측할 수 있는가 ?

이일옥 대한마취과학회 1996 Korean Journal of Anesthesiology Vol.30 No.3

Background: This study was to evaluate the relationship of preoperative autonomic tests to the labetalol effect on cardiovascular responses to intubation of geriatrics(65 years of age or older, n=23). The autonomic tests consisted of heart rate response to deep breathing(HRdb), Valsalva ratio(VR), 30/15 ratio(30/15) to assess parasympathetic function. The systolic blood pressure change response to standing(△ SBP) and mean arterial pressure change response to standing(△MAP) were to assess sympathetic function. Methods: These autonomic tests were taken preoperatively. At a separate time, labetalol 1.0 mg/kg was injected as a bolus 3 minutes before induction with thiopental sodium (4 mg/kg), succinylcholine (1 mg/kg). The anesthesia was maintained with enflurane, oxygen, nitrous oxide and vecuronium (0.08 mg/kg). The blood pressure and heart rate(HR) were recorded at one minute intervals for 5 minutes after intubation. The hypotension (SBP$lt;90 mmHg) or bradycardia (HR$lt;60 beats/minute) were recorded for 10 minut after intubation. After anesthesia, they were divided two groups according to presence(old abnormal group, n=10, who required intraoperative vasopressors) or absence(old normal group, n=13, who did not require intraoperative vasopressors) of hypotension or bradycardia. Results: The VR and △MAP revealed significant correlation with SBP and HR after intubation and 5 minutes later(p$lt;0.05). The autonomic test results revealed significant autonomic dysfunction(p$lt;0.05) among old abnormal group compared with old normal group. HR and SBP declined to a greater degree(p$lt;0.05) during induction of anesthesia in old abnormal group compared with old nortnal group. There was less(p$lt;0.05) increase in the same parameters following intubation in old abnormal group. The highest sensitive autonomic test was VR and the highest specific autonomic test was △MAP. Conclusions: Geriatric patients are at increased risk for cardiovascular instability during intubation. The preoperative evaluation with autonomic tests may be useful indentifying those at high risk for perioperative hypotension or bradycardia when pre-induction intravenous labetalol 1.0 mg/kg is indicated.

소아의 성장 발육하는 뇌와 마취

이일옥 대한마취통증의학회 2010 Anesthesia and pain medicine Vol.5 No.2

Neuronal cell death after general anesthesia has been documented in several immature animal models.The possibility of anesthesia- induced neurotoxicity during an uneventful anesthetic in neonates or infants has led to serious questions about the safety of pediatric anesthesia.However, the applicability of animal data to clinical anesthesia remains uncertain.In this review, the evidence of the effects of commonly used anesthetics on neural structures and neurocognitive function in newborn humans and animals.Experimental evidences and human studies were reviewed.A growing number of studies in immature animal models demonstrate degenerative effects of several anesthetics on neuronal structure. Several retrospective reviews evaluating neurocognitive function in children demonstrate temporary neurological sequela after prolonged anesthetic exposure in young children and larger studies identify long-term neurodevelopmental impairment after neonatal surgery and anesthesia.The evidence for anesthesia induced neurodegeneration in animal models is compelling and represent the challenge within the practice of pediatric anesthesiology, however, extends well beyond pediatric anesthesiology because the implicated drugs are widely used in a variety of settings of newborn and young children around the world.No data source until now is complete with this regard to the critical elements necessary to address this question: therefore, further investigations of this phenomenon are imperative both in animals and in young children and governments around the world will be needed to adequately address this critical issue.

Vecuronium 의 근이완 작용에 대한 Neostigmine 과 Pyridostigmine 의 조기 투여 효과에 대한 비교

이일옥,윤석민,김종욱 대한마취과학회 1991 Korean Journal of Anesthesiology Vol.24 No.3

To compare the time course of neostigmine and pyridostigmine antagonism of profound neuromuscular blockade (no-twitch: when no response to peripheral nerve stimulation could be elicited) induced by vecuronium, the authors studied 30 patients who were ASA Physical Status I or II undergoing minor surgery, free from neuromuscular, renal or hepatic dieases. Train-of Four[TOF] stimulation was applied to the ulnar nerve every ISseconds and the force of contraction of adductor pollicis muscle was recorded. In all patients, anesthesia was induced with thiopental sodium(5 mg/kg) and vecuronium (0.1 mg/kg), endotracheal intubation was performed at 100% depression of the T₁(the first response in the train-of-four sequence). Patients were randomly assigned to one of two groups Five minutes after intubation, when there was no detectable twitch response, each patient received either neostigmine(0.03 mg/kg) with atropine sulfate(0.02 mg/kg). Neuromuscular fuction in another ten subjects were allowed to recover spontaneously. The results were as follows; 1) Profound neuromuscular blockade was not rapidly antagonized by either neostigmine or pyridostigmine but the use of anticholinesterase was effeetive for recovery. 2) The results demonstrated that there were no difference in antagonism of vecuronium induced profound neuromuscular block between neostigmine and pyridostigmine. 3) The time to 100% depression of T₁ after vecuronium injection was 190.5±38.7 sec. 4) After anticholinesterase administration, in all groups, the changes of mean arterial pressure and heart rate were within ±10% of control after anticholinesterase dministration were observed.

국소 마취하 성인 편도절제술시 수술 전 투여한 Tiaprofenic Acid의 술후 제통 효과에 대한 관찰

이일옥 대한마취과학회 1998 Korean Journal of Anesthesiology Vol.35 No.4

Background : The aim of this study was to compare the pre-emptive effect of preoperative with postoperative tiaprofenic acid in adult local tonsillectomy. Methods : We compared in forty adults the effect of preoperative with postoperative tiaprofenic acid on pain after tonsillectomy in a double-blind, randomized study, which was approved by the Ethics Committee. Informed consents were obtained. Patients were allocated randomly to receive a tiaprofenic acid (200 mg) intravenously either before (n=20) or immediately after (n=20) surgery. Postoperative pain was rated by self-rating visual analog scale for the first 24 hours. Tiaprofenic acid (200 mg) was given when patient complained pain. Time to the first analgesic administration, total requirement of analgesics for 48 hours and the first time of swallowing 100 ml water were checked. Results : Postoperative 1 hour pain score of the preoperative group was significantly lower than postoperative groups (p<0.05). Times to the first analgesic administration, the ttal requirement of analgesics for 48 hours and the times of the first swallowing of 100 ml water were not significantly different between the two groups. Conclusions : Preoperative intravenous tiaprofenic acid (200 mg) in adult local tonsillectomy was effective on the reducing the intensity of the postoperative pain only 1 hour after operation. The use of preoperative tiaprofenic acid in adult local tonsillectomy was associated with a more calm recovery. The results of this study do not support the theory of preemptive analgesia. (Korean J Anesthesiol 1998; 35: 745∼750)

척추 마취시 환자의 체위, 천자 방법, 천자 방향에 따른 척추 천자 후 두통

이일옥 대한마취과학회 1995 Korean Journal of Anesthesiology Vol.29 No.1

Postdural puncture headache is one of the well-known complications of spinal anesthesia. The sitting position is adequate for perineal and urologic operations, or when obesity makes difficult identification of midline anatomy in the lateral position. This study was done to see the effect of position (lateral or sitting position during spinal anesthesia), needle bevel direction (parallel or vertical to longitudinal dural fiber), and angle of approach (paramedian or midline) on the incidence, onset, location, severity of postdural puncture headache in the 160 patients underwent spinal anesthesia with 25-gauge Quincke needles. We observed the following results: 1) The total incidence of postdural puncture headache was 8.1%(13 cases). 2) The incidence of postdural puncture headache were 6%(lateral position), 10%(sitting position), 3%(parallel to longitudinal dural fiber), 11%(vertical to longitudinal dural fiver), 8%(paramedian approach) and 9%(midline approach). A significant increase in incidence was found with 25-gauge Quincke needles when the bevels were oriented so as to be vertical rather than parallel to the longitudinal dural fibers. 3) The onset of postdural puncture headache were within 3 days after spinal anesthesia in the almost cases (92.3%). 4) The location of postdural puncture headache were frontal(31%), occipital(15%), temporal(8%), and whole region(46%). 5) According to the duration of postdural puncture headache, two day headache was 31%, four day one was 15%, six day one was 15%, and over six day one was 38%. A significant increase in duration was found with sitting position when the bevels were oriented so as to be vertical rather than parallel to the longitudinal dural fibers. 6) The treatments of postdural puncture headache were bed rest(20%), analgesics(54%), and epidural blood patch(31%). In conclusion, the significant increase in incidence and duraion were found with 25-gauge Quincke needles when the bevels were oriented so as to be vertical rather than parallel to the longitudinal dural fibers. (Korean J Anesthesiol 1995; 29: 112~117)

소아의 편측 수종 절제술과 환상 절제술시 Low-dose Ketamine의 술후 통증에 대한 효과

이일옥 대한마취과학회 1998 Korean Journal of Anesthesiology Vol.35 No.2

Backgrounds : Brief noxious stimuli are found to produce long-lasting neuronal sensitization. This cumulative depolarization results from the activation by glutamate of N-methyl-D-aspartic acid (NMDA) receptor. Ketamine at subanesthetic doses blocks the channel associated with the NMDA receptor. The aim of this study was to investigate the pre-emptive effect of ketamine in children after circumcision with unilateral hydrocelectomy. Materials and Methods : We have compared the effect of preoperative ketamine (0.3 mg/kg) in a double-blind, randomized study, which was approved by the local Ethics Committee. Informed consents were obtained from their parents. After induction of anesthesia, patients were allocated randomly to receive a ketamine (n=20) or placebo (n=20) intravenously before surgery. Postoperative pain was rated on a faces scale for the first 24 hours. If pain occurred, children received tiaprofenic acid in a dose related to body weight. The cumulative pain score, the time of the first requirement of analgesics, and total requirement of analgesics for 24 hours were also checked. Results : The pain scores at 4, 5, 6, 7, 8, 9, and 12 hours after operation were significantly low in ketamine group. The cumulative pain scores for the first 8 hours and the total requirements of analgesics were significantly low in ketamine group. The time of the first requirement of analgesic was significantly delayed in ketamine group. Conclusions : Preoperative ketamine in the pediatric circumcision with unilateral hydrocelectomy is effective on the reducing the intensity of the postoperative pain. The results of this study support the theory of pre-emptive analgesia of ketamine. (Korean J Anesthesiol 1998; 35: 334∼340)

탄재 내장 Chromite 의 환원거동에 미치는 FeO , Fe 의 영향

이일옥,정원섭,김동의 대한금속재료학회 1990 대한금속재료학회 학술대회 개요집 Vol.1990 No.0

철광석의 환원반응속도에 미치는 광석입경의 영향

이일옥,정우창,소야양일,정원변,강흥원 대한금속재료학회(대한금속학회) 1997 대한금속·재료학회지 Vol.35 No.3

In order to investigate the effect of particle size on gaseous reduction rate of iron ore, two kinds of iron oxide pellets of different diameters were reduced with CO-CO₂ gas mixture. Results were analyzed using two models, the intermediate model and the unreacted-core model. From the analysis of the former model, the effective diffusivity through product layer, D_s, the effective diffusivity through reactant layer, D_(so), and volume-based chemical reaction rate constant k_v, were not changed with particle diameter while Thiele's modulus φ and effectiveness factor, E₁ were changed. From that of the latter model, the effective diffusivity through product layer, D_s was not varied with particle diameter, while the interface chemical reaction rate constant, k_c was varied. Investigation revealed that particle size affected a gas-solid reaction modules and that this affected gaseous reduction rate.