The Effect of Blood Pressure on Cerebral Perfusion During Vascular Surgery
The Effect of Blood Pressure on Cerebral Perfusion and Oxygenation During Vascular Surgery
연구 개요
상세 설명
Background: Induction of anesthesia reduces mean arterial pressure (MAP) and cerebral blood flow is normally considered to be maintained by cerebral autoregulation despite changes in MAP between 60 - 150 mmHg and standard of care during anesthesia is to maintain MAP above 60 mmHg. Vascular surgical patients are often elderly with hypertension and atherosclerotic manifestations that may impair cerebral autoregulation of importance for anesthesia-induced reduction in blood pressure.
Objective: To assess the effect of MAP for preservation of cerebral blood flow and oxygenation during vascular surgery.
Hypothesis: The primary hypothesis is that during general anesthesia in vascular surgical patients, cerebral blood flow velocity and oxygenation is higher with MAP maintained at 80-90 mmHg, compared with a MAP maintained at a minimum of 60 mmHg.
MAP is controlled in both groups using continuous infusion of phenylephrine. Phenylephrine is used as a tool in order to assess the effect of MAP on the cerebral circulation. In both groups, central blood volume is optimized by infusion of lactated Ringer´s solution using a goal directed fluid therapy following induction of anaesthesia and before commencement of phenylephrine infusion.
Trial size: The investigators will include 40 participants (2 x 20) in order to detect or reject a 20% difference in middle cerebral artery velocity with a type I error risk of 5% and a type II error risk of 20% (power at 80%). Interim analysis will be conducted after inclusion of 20 patients (2 x 10). Excluded patients will be replaced.
연구 유형
단계
- 해당 없음
연락처 및 위치
연구 장소
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Copenhagen Ø, 덴마크, 2100
- Rigshospitalet, Anæstesi og Operationsklinikken 2043
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참여기준
자격 기준
공부할 수 있는 나이
건강한 자원 봉사자를 받아들입니다
연구 대상 성별
설명
Inclusion Criteria:
- Patients undergoing one of the following vascular surgical interventions in general anesthesia: Infra-inguinal bypass, femoro-femoral cross-over bypass or iliofemoral bypass surgery.
- Age > 18 years. Informed consent
Exclusion Criteria:
- Use of monoamine oxidase inhibitors
- Allergy to phenylephrine
- Patients that cannot cooperate during examination
- Dementia defined as Mini-Mental State Examination < 24
- Anesthesia within the last 30 days
- Alcohol consumption at or above 420 grams per week
- Lack of fluency in written and spoken Danish
- Severe hearing and vision impairment
- Neurological disease
공부 계획
연구는 어떻게 설계됩니까?
디자인 세부사항
- 주 목적: 지지 요법
- 할당: 무작위
- 중재 모델: 병렬 할당
- 마스킹: 삼루타
무기와 개입
참가자 그룹 / 팔 |
개입 / 치료 |
|---|---|
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실험적: MAP maintained at 80 mmHg
During anesthesia MAP is maintained at 80 - 90 mmHg MAP using continuous infusion of phenylephrine.
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Intervention group, MAP is maintained at 80 - 90 mmHg during anesthesia using continuous infusion of phenylephrine.
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활성 비교기: MAP maintained at 60 mmHg
During anesthesia MAP is maintained at minimum of 60 mmHg using continuous infusion of phenylephrine.
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Control group, MAP is maintained at minimum of 60 mmHg during anesthesia using continuous infusion of phenylephrine.
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연구는 무엇을 측정합니까?
주요 결과 측정
결과 측정 |
측정값 설명 |
기간 |
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Middle cerebral artery blood velocity
기간: During surgery
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Middle cerebral artery blood velocity measured in [cm/s] assessed by transcranial Doppler.
Changes in middle cerebral artery blood velocity reflects changes in cerebral blood flow.
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During surgery
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2차 결과 측정
결과 측정 |
측정값 설명 |
기간 |
|---|---|---|
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Change in serum S100B as compared between subjects in the control- and intervention groups
기간: Blood is sampled 10 min prior to induction of anesthesia and at the end of surgery
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Serum concentrations of S100B, a marker of neuronal injury
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Blood is sampled 10 min prior to induction of anesthesia and at the end of surgery
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Change in serum neuron-specific enolase as compared between subjects in the control- and intervention groups
기간: Blood is sampled 10 min prior to induction of anesthesia and at the end of surgery
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Serum concentrations of neuron-specific enolase, a marker of neuronal injury
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Blood is sampled 10 min prior to induction of anesthesia and at the end of surgery
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Regional cerebral oxygenation as compared between subjects in the control- and intervention groups
기간: During surgery
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Frontal lobe oxygenation measured as the percentage of oxyhemoglobin of total hemoglobin [%] evaluated by near-infrared spectroscopy
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During surgery
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Cardiac output as compared between subjects in the control- and intervention groups
기간: During surgery
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Cardiac output measured in [l/min] evaluated by pulse contour analysis of the arterial blood pressure curve
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During surgery
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Stroke volume as compared between subjects in the control- and intervention groups
기간: During surgery
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Stroke volume measured in [ml/min] evaluated by pulse contour analysis of the arterial blood pressure curve
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During surgery
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공동 작업자 및 조사자
수사관
- 수석 연구원: Niels D. Olesen, MD, Rigshospitalet, Anæstesi og Operationsklinikken 2043, Denmark
연구 기록 날짜
연구 주요 날짜
연구 시작 (예상)
기본 완료 (예상)
연구 완료 (예상)
연구 등록 날짜
최초 제출
QC 기준을 충족하는 최초 제출
처음 게시됨 (추정)
연구 기록 업데이트
마지막 업데이트 게시됨 (실제)
QC 기준을 충족하는 마지막 업데이트 제출
마지막으로 확인됨
추가 정보
이 정보는 변경 없이 clinicaltrials.gov 웹사이트에서 직접 가져온 것입니다. 귀하의 연구 세부 정보를 변경, 제거 또는 업데이트하도록 요청하는 경우 register@clinicaltrials.gov. 문의하십시오. 변경 사항이 clinicaltrials.gov에 구현되는 즉시 저희 웹사이트에도 자동으로 업데이트됩니다. .
MAP maintained at 80 mmHg에 대한 임상 시험
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Weill Medical College of Cornell UniversityNational Heart, Lung, and Blood Institute (NHLBI)완전한