• 제목/요약/키워드: electrical injury

검색결과 173건 처리시간 0.022초

초저체온하 대동맥수술 환자에서 완전 순환차단의 안전한 체온 및 기간에 대한 연구 - 뇌파 Compressed Spectral Array의 임상적 응용 - (Clinical Application of Compressed Spectral Array During Deep Hypothermia)

  • 장병철;유선국
    • Journal of Chest Surgery
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    • 제30권8호
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    • pp.752-759
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    • 1997
  • 복합 심장질환이나 대동맥궁 수술시 뇌손상을 보호하기 위하여 오래전부터 초저체온하 완전순환정지법 을 이용하고 있다. 수술후 뇌손상을 예방하기 위하여 여러 방법들을 이용하여 왔으며, 1994년이후 저자들은 뇌대사를 감시하기 위한 방법으로 수술중 뇌파감시를 하고 있다. 저자들은 심장수술실에 사용이 편리한 뇌 파 압축 스펙트럼 정렬(compressed spectral array; CSA) 시스템을 개발하여 이를 대동맥수술시 초저체온 및 설 전순환차단하에 뇌파감시에 적용하여 이의 유용성을 검증하고, 초저체온하 뇌파를 연속감시하여 뇌파가 소 실되고 다시 나타나는 온도를 확인하여 순환정지의 안전한 온도와 시간을 연구하였다. 급성 대동맥박리증 3 례와 대동맥궁 대동맥류 3례(2례는 가성)의 대동맥질환 환자를 연구대상으로 하였다. 직장과 식도체온을 연 속 감시하였으며,마취후 뇌파를 연속감시하였다. 대상환자들중 3례는 초저체온하 완전순환차단하에 수술을 하였으며, 3례는 초저체온하 선택적 뇌관류하에(500 700Ml분) 수술을 하였다. 환자의 체온을 하강하여 뇌 파가 소실된 후 약 3분 후에 순환정지나 선택적 뇌관류를 하였다. 뇌파가 소실된 체온은 직장\ulcorner온이 $16.1^{\circ}C-22.1^{\circ}C(평균:$ $18.4\pm2.0),$ 식도체온이 $12.7^{\circ}C~16.4^{\circ}C(평균:$ $14.7\pm1.6)였다.$ 완전순환차단 환자의 경우 뇌 허혈 시간은 각각 30, 36, 및 56분이었으며, 뇌관류 환자의 경우 각각 41, 56, 92분이었다. 수술중 뇌파가 다시 나 타난 시간 및 체온은(증례 3~6) 5~23분후에 직장체온이 $14.1^{\circ}C~20.3^{\circ}C,$ 식도체온이 $11.7^{\circ}C~15.4^{\circ}C에서$ 나타났다. 수술후 뇌손상의 증상은 없었으며,수술과 관련된 사망은 없었다. 이상의 결과로 식도체온이 $16^{\circ}C이하에서도$ 뇌파가 23분이내에 다시 나타난 것으로 보아 식도체온이 $15^{\circ}C이하는$ 되어야 약 30분간의 완전순환 차단에 안전하리라 생각되었으며, 대동맥 수술시 CSA를 이용한 뇌파감시는 전기뇌활동을 감시하는데 유용 한 방법으로 생각되었다.

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전침자극이 흰쥐척수후각세포의 유해자극반응에 미치는 효과의 특성 (Characterization of Electroacupuncture Effects on the Responses of Rat Dorsal Horn Neurons to Noxious Stimulation)

  • 신홍기;박동석;이서은;김진혁
    • Journal of Acupuncture Research
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    • 제19권4호
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    • pp.167-182
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    • 2002
  • This experiment was designed to investigate the effects of electroacupuncture (EA) on chronic pains and factors that affected EA effects. The responses of wide dynamic range (WDR) cells to electrical stimulation of $A{\delta}$ & C afferent fibers were used as an index of pain in rats with chronic pains induced by intraplantar injection of complete Freund's adjuvant or peripheral nerve injury. In rats with chronic pains, low (2Hz) and high (100Hz) frequency EA stimulation applied to zusanli caused the inhibition of WDR cell responses in about 60% of rats and the inhibitory actions were dependent on the stimulus strength. EA stimulation also induced an excitation of WDR cell responses in 23.9% of rats and no effect in 15.8% of rats. However, it seemed that in normal rats compared to the rat with chronic pains, the incidence of which EA stimulation caused the excitation or no effect was high. Reversible spinalization almost completely blocked EA-induced inhibitory or excitatory effects. EA stimulation more frequently induced the excitation of WDR cell responses in lightly anesthetized (0.6%) rats and the enhanced responses of WDR cells were inhibited by EA stimulation in the rat anesthetized with 1.5% enflurane. These experimental findings suggest that in rats with chronic pain, EA stimulation inhibited WDR cell responses to slow $A{\delta}$ and C fiber stimulation and EA-induced inhibitory action was under the control of descending inhibitory system and degree of anesthesia.

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이하선에 발생한 안면신경 신경초종의 치험례 (FACIAL NERVE SCHWANNOMA IN PAROTID GLAND: A CASE REPORT)

  • 최세경;최종명;김현실;김형준;차인호;남웅
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제32권1호
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    • pp.68-71
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    • 2010
  • Facial nerve schwannomas (FNSs) are usually painless, slow-growing, and without specific symptoms, so that early diagnosis may be difficult. They are particularly liable to being misdiagnosed as parotid gland origin benign tumor before surgery, which can lead to unnecessary parotidectomy or unexpected facial nerve injury. To prevent these complications, it is important that the correct diagnosis is performed at least in intraoperative time. When an adhesion between the mass and the facial nerve is exist or when electrical stimulation of the mass triggers facial movement, FNS is highly suggested diagnosis. In such cases, frozen section analysis should always be performed. In this case, the pre-operative diagnosis from clinical examination and MRI was pleomorphic adenoma. However, intraoperative features led us to suspect that the mass originated from facial nerves, and intraoperative frozen section analysis yielded results consistent with a schwannoma. Based on this intraoperative diagnosis, we carried out a successful conservative treatment with preservation of facial nerve.

Impedance Parameter Variations at Intravenous (IV) Infiltration Using Bioelectrical Impedance: A Pilot Study

  • Kim, Jaehyung;Lee, Mansup;Baik, Seungwan;Kim, Gunho;Hwang, Youngjun;Jeon, Gyerok
    • 한국멀티미디어학회논문지
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    • 제20권10호
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    • pp.1678-1688
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    • 2017
  • Infiltration is one of detrimental problems occurring in nursing or medical settings. Early detection of infiltration is essential to minimize the risk of injury from infiltration. To perform a preliminary study on the point of care and automated infiltration detection system, bioelectrical impedance was investigated using bioelectrical impedance analyzer. We would like to report experimental results that allow impedance parameters to effectively distinguish infiltration. Electrodes were attached to both sides of the transparent dressing on the fusion site where IV solution was being infused. Then, impedance parameters before and after infiltration were measured as a function of time and frequency. The experimental results are as follows. After infiltration was intentionally induced by puncturing the vein wall with a needle, the resistance gradually decreased with time. That is, when an alternating current having a frequency of 20 kHz was applied to the electrodes, the resistance gradually decreased with time, reflecting the accumulation of IV solution in the extracellular fluid since the current could not pass through the cell membrane. Impedance parameters and equivalent circuit model for human cell were used to examine the mechanism of current flow before and after infiltration, which could be used for early detection of infiltration.

만성통증이 유발된 흰쥐에서 관찰된 침진통효과의 세로토닌성 기전 (Activation of spinal Serotonergic Receptor Contributes to Electroacupuncture Analgesia in Rat with Chronic Pain)

  • 박동석;신홍기;이경희
    • 대한한의학회지
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    • 제26권3호
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    • pp.239-248
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    • 2005
  • Objectives : Electroacupuncture (EA)-induced analgesia has been known to be mediated through the activation of opioid, noradrenergic and serotonergic receptors. However, little study on serotonergic mechanism has been performed in an animal model of chronic pain. The present study was designed to elucidate the type of serotonergic receptors responsible for EA analgesia in the chronic pain model. Methods : In rats with complete Freund's: adjuvant-induced inflammation and spinal nerve injury, spinal wide dynamic range (WDR) cell responses to graded electrical stimulation of afferent C fiber were recorded before and after spinal application of selective 5-hydroxytryptamine (5-HT) receptor antagonists. EA stimulation (2Hz, 0.5msec, 3mA) was applied to the contralateral Zusanli point for 30 min. Results : In both models of chronic pain, WDR cell responses were greatly inhibited after EA stimulation. EA-induced inhibition of WDR celt responses was significantly attenuated by spinal application of non-selective 5-HT receptor antagonist, dihydroergocristine Of 5-HT receptor antagonists tested, 5-HT1A (WAY 100635) and 5-HT2 (LY53857) receptor antagonists strongly reduced an ability of EA stimulation to inhibit WDR cell responses. However, 5-HT1B (GR55562) and 5-HT3 (LY278584) receptor antagonists also had weak but significant blocking action on EA-induced inhibitory effect on chronic pain. Conclusions : Dorsal hem cell responses, afferent C fiber stimulation, chronic pain, electroacupuncture, serotonergic receptors.

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교감신경 중재 통증 보유 모델 쥐에서 교감신경 활동에 의한 배근절세포의 흥분성 (Sympathetic Excitation of Afferent Neurons within Dorsal Root Ganglia in a Rat Model of Sympathetically Medicated Pain)

  • 임중우;강민정;백광세;남용택
    • The Korean Journal of Pain
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    • 제9권1호
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    • pp.26-38
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    • 1996
  • In a normal state, sympathetic efferent activity does not elicit discharges of sensory neurons, whereas it becomes associated with and excites sensory neurons in a pathophysiological state such as injury to a peripheral nerve. Although this sympathetic-sensory interaction is reportedly adrenergic, involved subtypes of adrenoreceptors are not yet clearly revealed. The purpose of this study was to determine which adrenorceptor subtypes were involved in sympathetic-sensory interaction that was developed in rats with an experimental peripheral neuropathy. Using rats that received a tight ligation of one or two of L4-L6 spinal nerves 10~15 days previously, a recording was made from afferent fibers in microfilaments teased from the dorsal root that was in continuity with the ligated spinal nerve. Electrical stimulation of sympathetic preganglionic fibers in T13 or L1 ventral root (50 Hz, 2-5 mA. 0.5 ms pulse duration, 10 sec) was made to see if the activity of recorded afferents was modulated. About half of afferents showing spontaneous discharges responded to sympathetic stimulation, and had the conduction velocities in the A-fiber range. Most of the sympathetically induced afferent responses were excitation. This sympathetically induced excitation occurred in the dorsal root ganglion (DRG), and was blocked by yohimbine (${\alpha}_2$ blocker), neither by propranolol ($\beta$ blocker) not by prazosine (${\alpha}_1$ blocker). The results suggest that after spinal nerve ligation, sympathetic efferents interact with sensory neurons having A-fiber axons in DRG where adrenaline released from sympathetic nerve endings excites the activity of sensory neurons by acting on 2-adrenoreceptors. This 2-adrenoreceptor mediated excitation of sensory neurons may account for sympathetic involvement in neuropathic pain.

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척수 아교질 신경세포의 흥분성에 대한 활성산소종의 역할 (Roles of Reactive Oxygen Species on Neuronal Excitability in Rat Substantia Gelatinosa Neurons)

  • 최정희;김재효;임성준;박병림;권강범
    • 동의생리병리학회지
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    • 제21권2호
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    • pp.432-437
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    • 2007
  • Reactive oxygen species (ROS) are toxic agents that may be involved in various neurodegenerative diseases. Recent studies indicate that ROS are also involved in persistent pain through a spinal mechanism. In the present study, whole cell patch clamp recordings were carried out on substantia gelatinosa (SG) neurons in spinal cord slice of neonatal rats to investigate the effects of ROS on neuronal excitability and excitatory synaptic transmission. In current clamp condition, tert-buthyl hydroperoxide (t-BuOOH), an ROS donor, induced a electrical hyperexcitability during t-BuOOH wash-out followed by a brief inhibition of excitability in SG neurons. Application of t-BuOOH depolarized membrane potential of SG neurons and increased the neuronal firing frequencies evoked by depolarizing current pulses. Phenyl-N-tert-buthylnitrone (PBN), an ROS scavenger, antagonized t-BuOOH induced hyperexcitability. IN voltage clamp conditions, t-BuOOH increased the frequency and amplitude of spontaneous excitatory postsynaptic currents (sEPSCs). In order to determine the site of action of t-BuOOH, miniature excitatory postsynaptic currents (mEPSCs) were recorded. t-BuOOH increased the frequency and amplitude of mEPSCs, indicating that it may modulate the excitability of the SG neurons via pre- and postsynaptic actions. These data suggest that ROS generated by peripheral nerve injury can induce central sensitization in spinal cord.

수술적 방법으로 유도된 3단계 고도(高度) 발목염좌 모델에서 혈위(穴位)에 따른 전침효과의 비교 (Comparison Study for Analgesic Effects of Electroacupuncture on Surgical Ankle Sprain Model Classified as Grade 3 in Rats)

  • 양승범;손인철;이성호;조상훈;김재효
    • Korean Journal of Acupuncture
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    • 제30권1호
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    • pp.47-55
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    • 2013
  • Objectives : The purpose of this study was to determine whether electroacupuncture(EA) is effective in reducing pain on the severe ankle sprain classified as grade 3 in rats. Methods : The severe(grade 3) ankle sprain model was induced surgically by ankle ligament injury(the anterior talofibular, the calcaneofibular and the posterior talofibular) in the Sprague-Dawley rats(180~250 g). The effects of EA on weight bearing forces(WBR) of the affected foot were examined in a rat model of ankle sprain. EA was applied to either SI6, ST37, GB34, GB39 or GB42 acupoints by trains of electrical pulses(2 Hz, 1 ms pulse width, 2 mA intensity) for 15 min. Results : Cutting of the lateral ankle ligament complex produced the severe ankle sprain symptoms as grade 3. EA of the contralateral SI6 resulted in more analgesic effect than one of ipsilateral SI6 even though there was significant effect. EA of the ipsilateral GB34 and GB39 produced potent analgesic effects on the surgical ankle sprained pain behaviors. However, there were no significant analgesic effects in the contralateral GB34 and GB39 EA groups. In addition, both side of ST37 and GB42 did not result in analgesic effect on the surgical ankle sprained rat. Conclusions : The data suggest that EA induced analgesia shows point specificity on the severe ankle sprained pain model classified as grade 3.

Hall 센서를 이용한 엘리베이터 와이어 로프의 비파괴 검출시스템의 개발 (Development of Nondestructive Detecting System for Elevator Wire Ropes using Hall-effect Sensors)

  • 김성덕
    • 센서학회지
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    • 제10권1호
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    • pp.33-41
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    • 2001
  • 와이어 로프는 무거운 중량을 안전하게 운반하거나 기계적인 에너지를 빠르게 전송하는 곳과 같은 산업응용 분야에 광범위하게 사용되어 왔다. 특히, 운전 중 엘리베이터의 와이어 로프가 파손되면 큰 재산 상 손실과 주변 인명의 심각한 상해를 초래할 수 있다. 따라서, 와이어 로프의 정기적인 검사는 매우 중요하다. 와이어 로프의 고장 검출은 로프의 구조, 특성, 결함 특성, 검출방법과 신호처리 방법에 대한 기본적인 이해가 요구된다. 이 연구에서는 엘리베이터에 노화된 와이어 로프에 대한 마모, 단선, 부식과 형붕괴와 같은 결함을 검출하기 위하여, Hall 센서를 결합한 새로운 결함 검출시스템의 개발에 대하여 다룬다. 휴대용 계측기로서 검출기를 사용하기 위하여, Hall 센서를 가진 센싱 부분과 아날로그 신호처리 및 프로그램의 제작에 대한 몇 가지 특성들이 서술되었다. 제작된 검출시스템에 대한 실험과 실장시험 결과 역시 제시되었다. 그 결과, 검출시스템은 사용 중인 노화된 와이어 로프의 결함을 검출하는데 양호한 효율성을 갖는다는 것을 확인하였다.

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스마트 거울을 활용한 실시간 자세교정 피트니스 시스템 (Fitness System for Correcting Real-time Posture Using Smart Mirror)

  • 서재식;신민호;문미경
    • 전기전자학회논문지
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    • 제23권1호
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    • pp.74-79
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    • 2019
  • 인구 고령화와 웰빙 열풍으로 인해 건강관리 욕구가 증가하면서 피트니스에 대한 관심은 점점 더 높아지고 있다. 사람들은 운동을 하기 위해 헬스장을 가지만, 많은 이들이 운동하는 방법을 몰라 운동 순서나 운동 자세를 틀리게 하는 경우가 많다. 이러면 운동 효과도 미비할 뿐만 아니라 부상의 위험도 커진다. 본 논문에서는 스마트 거울 앞에서 영상을 보며 혼자서 운동을 따라 할 수 있고 운동 자세가 잘못되었을 경우 실시간으로 틀린 곳을 확인시켜주는 스마트 거울을 활용한 피트니스 시스템의 개발 내용에 대해 기술한다. 이 시스템을 사용함으로써 사람들은 혼자서도 트레이너의 도움 없이 바른 자세로 운동을 할 수 있게 될 것이며, 이로 인해 그룹 또는 개인 트레이너를 기다려야 하는 시간이나 비용의 제약에 얽매이지 않고 운동을 할 수 있게 될 것이다.