Evaluation of Possible Neurotoxicity of Anesthesia Guided by Olfactory Changes in Middle-aged Patients
试验速览
- 阶段
- 不适用
- 入组人数
- 600
- 试验地点
- 1
- 主要终点
- olfactory threshold
研究概览
简要总结
for the last 20 years, the increasing reports from non-human studies have raised suspicion that general anesthetics may cause neurotoxic changes in the developing brain that lead to adverse neurodevelopmental outcomes later in life.there are several case reports of reversible smell and taste dysfunction following exposure to general anesthesia suggesting a possible relationship between anesthetic agents and olfactory dysfunction.
this study is to assess the possible neurotoxicity of sevoflurane,isoflurane,and propofol based anesthesia guided by olfactory changes
详细描述
the primary inhibitory neurotransmitter GABA is found in neuronal synapses involving olfactory bulb. So, the involvement of common GABA pathway implies a possible interaction of general anesthetics with olfactory function.
olfactory identification is an associative memory which is found to be facilitated by action of melatonin. involvement of GABA receptor in the transfer of light information from suprachiasmatic nuclei to pineal gland suggests possible interaction of melatonin and anesthetic agents.
the aim of the study is to evaluate the possible neurotoxicity of sevoflurane,isoflurane,and propofol based anesthesia guided by olfactory changes
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 50 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •patients aged 18-50 years
- •American society of Anesthesiologists' physical status I and II
- •elective surgery of duration 90-120 minutes
排除标准
- •patients's refusal
- •recent airway infection
- •allergic rhinitis
- •nasal polyps
- •history of alcoholism
- •pregnancy
- •menstruating female
- •mental retardation
- •psychiatric illness
- •neurosurgical or oto-rhino-laryngeal surgery
- •history of olfactory deficits or cognitive impairment
- •CNS disease e.g. epilepsy
- •history of first degree relative with alzheimer's disease,dementia, or cognitive dysfunction
- •those who are unable to answer the tests themselves
研究组 & 干预措施
sevoflurane
surgical procedures which will be performed under general anesthesia and sevoflurane will be used for maintenance of anesthesia
干预措施: Anesthesia Agent (Drug)
regional anesthesia
surgical procedures which will be performed under intrathecal anesthesia without sedation
干预措施: Anesthesia Agent (Drug)
isoflurane
surgical procedures which will be performed under general anesthesia and isoflurane will be used for maintenance of anesthesia
干预措施: Anesthesia Agent (Drug)
propofol
surgical procedures which will be performed under general anesthesia and propofol infusion will be used for maintenance of anesthesia
干预措施: Anesthesia Agent (Drug)
结局指标
主要结局
olfactory threshold
时间窗: olfactory threshold will be measured at 12 hours preoperative then at 6, 24 and 48 hours postoperative
we will use (10 dilutions) of 4% n-butyl alcohol. The odorant and a blank will be presented to the participant. The test will be progressed from weaker-to-stronger concentrations of odorant. Two bottles will be presented to each participant, an odorant bottle and an identical bottle filled with distilled water. The participant will sniff each one for 9 seconds and then will chose which one smelled stronger. If the participant is incorrect at one concentration, the next higher concentration will be presented. When the correct choice is made, the same concentration of odorant will be presented to the participant until four consecutive correct responses are given.
次要结局
- serum melatonin concentrations(serum melatonin will be measured at 12 hours preoperative then at 6, 24 and 48 hours postoperative)
- olfactory identification(Smell identification will be measured at 12 hours preoperative then at 6, 24 and 48 hours postoperative)
- cognitive dysfunction(Cognitive dysfunction will be evaluated at 12 hours preoperative then at 6, 24 and 48 hours postoperative)
研究者
Mona Raafat Elghamry
principal investigator
Tanta University