The Relationship Between Different Doses of Propofol and the Occurrence of Dreams in Short Surgery Under General Anesthesia

Study Overview
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Brief Summary
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Dreams are a remarkable experiment in psychology and neuroscience, conducted every night in every sleeping person. 74% of awakenings from REM sleep resulted in recall of a dream, as compared with only 9% of awakenings from NREM sleep. The association between dreaming and REM sleep was subsequently replicated by many other investigators; typically, around 80% of REM awakenings yield dreams. It became clear over time that there is a good deal of mental activity that occurs during NREM sleep. Typically, it is more thought like, fragmentary, and related to daily concerns than the vivid, hallucinatory, predominantly visual narratives that are most commonly reported from REM sleep. But even this distinction appears not to be absolute. There is now wide acceptance of the view that some dreaming that is indistinguishable from REM sleep dreaming occurs in NREM sleep, most frequently in the sleep-onset period. General anesthesia causes a drug-induced state of unconsciousness and is a non-physiological process that is similar to natural sleep. Patients receiving propofol for maintenance of general anesthesia often report higher incidences of dreaming than patients maintained with volatile anesthetics. One explanation is that propofol and volatile anesthetic have different pharmacological effects in the central nervous system. An alternative explanation is that propofol is associated with more rapid emergence from anesthesia than the older volatile anesthetics, allowing patients to report their dreams before they are forgotten. In order to further verify the hypothesis, the investigators choose gynecological general anesthesia to observe whether the generation of dreams is related to the dose of general anesthesia maintenance .

Official Title
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The Relationship Between Different Doses of Propofol and the Occurrence of Dreams in Short Surgery Under General Anesthesia

Conditions
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Dreaming, General Anesthesia

Intervention / Treatment
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* Drug: Propofol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: between 18 and 70 years with an ASA physical status of I or II Exclusion Criteria: presence of sleep disorders pain syndrome cardiovascular disease sleep apnea syndrome psychosis history of opioid usage history of abnormal operation or anesthesia recovery unwillingness to provide informed consent a patient with a language communication disorder

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low maintenance dose propofol group<br>The low maintenance dose propofol group was maintained at 4-6 mg/kg/h | Drug: Propofol<br>* The low maintenance dose propofol group was maintained at 4-6 mg/kg/h ；and The high maintenance dose propofol group was maintained at 8-12 mg/kg/h<br>|
| Experimental: High maintenance dose propofol group<br>The high maintenance dose propofol group was maintained at 8-12 mg/kg/h | Drug: Propofol<br>* The low maintenance dose propofol group was maintained at 4-6 mg/kg/h ；and The high maintenance dose propofol group was maintained at 8-12 mg/kg/h<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean blood pressure (systolic and diastolic) | record mean blood pressure during the surgery | 5 minutes after entering the operation room | 
| Mean blood pressure (systolic and diastolic) | record mean blood pressure during the surgery | Anesthesia induction to fall asleep | 
| Mean blood pressure (systolic and diastolic) | record mean blood pressure during the surgery | at the end of surgery | 
| Mean blood pressure (systolic and diastolic) | record mean blood pressure during the surgery | Upon awakening from anesthesia | 
| Mean blood pressure (systolic and diastolic) | record mean blood pressure during the surgery | leaving the operation room | 
| heart rate | record heart rate during the surgery | entering the operation room | 
| heart rate | record heart rate during the surgery | Anesthesia induction to fall asleep | 
| heart rate | record heart rate during the surgery | at the end of surgery | 
| heart rate | record heart rate during the surgery | Upon awakening from anesthesia | 
| heart rate | record heart rate during the surgery | leaving the operation room | 
| BIS | record BIS during the surgery | entering the operation room | 
| BIS | record BIS during the surgery | Anesthesia induction to fall asleep | 
| BIS | record BIS during the surgery | at the end of surgery | 
| BIS | record BIS during the surgery | Upon awakening from anesthesia | 
| BIS | record BIS during the surgery | leaving the operation room | 
| Total dose of propofol | record total dose of propofol | at the end of surgery | 
| Dream | Dreaming during anesthesia was defined as any experience that was described by the patient as dreaming and was thought by the patient to have occurred between the induction of anesthesia and the first moment of consciousness after anesthesia.27 Awareness was defined as postoperative recall of intraoperative events. All patients who reported dreaming were considered to be dreamers for the purpose of the analyses, whether or not they could remember the narrative of the dream. However, only dreaming reports where the narrative was remembered were classified using five-point Likert scales as follows. Emotional content (1 very negative; 5 very positive) ● Memorability (1 can't remember narrative of dream; 5 most memorable ever) ● Visual vividness (1 not at all vivid; 5 most vivid ever) ● Amount of sound (1 no sound; 5 most sound ever) | at the end of surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative adverse effects | record postoperative adverse effects | 24 hours after surgery |