Regimen of Alfentanil in Propofol Sedative Fibro-bronchoscopy

Phase 4

Completed

Interventions: Drug: Alfentanil
Drug: Normal saline
Device: Targeted controlled infusion
Drug: Propofol

Brief Summary: Alfentanil (Alf) is used in combination with Propofol (Pro) in fiber-bronchoscopy and in many other conscious sedation procedures. Alf and Pro have the characteristic of rapid anesthetic onset and quick recovery, synergic sedative effect and unwanted side effects too. However, the amount of Alf needed in combination with Pro for induction and the timing of administration was no standardized. The investigators designed this study to evaluate the optimal regimen, dose and timing of Alf in Target-Controlled infusion (TCI) of Pro for flexible bronchoscopy sedation, and also to evaluate the influence of variable regimen of Alf and Pro on hypoxemia, hypotension, cough severity, and Pro injection related pain.

Detailed Description: Alfentanil (Alf) is used in combination with Propofol (Pro) in fiber-bronchoscopy and in many other conscious sedation procedures. Alf and Pro have the characteristic of rapid anesthetic onset and quick recovery, synergic sedative effect and unwanted side effects too. However, the amount of Alf needed in combination with Pro for induction and the timing of administration was no standardized. The investigators designed this study to evaluate the optimal regimen, dose and timing of Alf in Target-Controlled infusion (TCI) of Pro for flexible bronchoscopy sedation.

Method: patients will be enrolled and assigned randomly into five groups. In group 1, normal saline two minutes before and Alf 2.5μg/kg before Pro were given; In group 2, normal saline two minutes before and Alf 5μg/kg before Pro were given; In group 3, Alf 2.5μg/kg two minutes before and normal saline before Pro were given; In group 4: Alf 5μg/kg two minutes before and normal saline before Pro were given; in group 5, normal saline two minutes and before Pro were given.

Concentration of effect site to loss of consciousness (LOC), dose of Pro to LOC, and induction time of variable regimen, as well as hypoxemia, hypotension, cough severity, and Pro injection related pain will be recorded and analyzed.

Recruitment & Eligibility

Inclusion Criteria

Exclusion Criteria

any physical, psychiatric, social problem that avoid from conscious level evaluation,
hypersensitivity or allergy to Propofol, Alfentanil
severe chronic obstructive pulmonary disease (forced expiratory volume in 1 s ,50% of predicted value, or requirement for oxygen therapy)
unstable haemodynamic status (defined as a heart rate < 60 or ≧ 120 bpm and/or
a systolic blood pressure (SBP) < 100 or ≧ 180 mmHg)
predictable difficult upper airways (Mallampati classification score of IV)
severe obstructive sleep apnea with apnea hypopnea index (AHI) > 45
Body mass index (BMI) more than 42 in male and 35 in female
renal insufficiency
liver cirrhosis

Arm && Interventions

Group	Intervention	Description
Group2	Normal saline	Alfentanil 5μg/kg before propofol
Group2	Targeted controlled infusion	Alfentanil 5μg/kg before propofol
Group 3	Normal saline	Alfentanil 2.5μg/kg two minutes before propofol
Group 4	Normal saline	Alfentanil 5μg/kg two minutes before propofol
Group1	Alfentanil	Alfentanil 2.5μg/kg before propofol
Group1	Normal saline	Alfentanil 2.5μg/kg before propofol
Group2	Alfentanil	Alfentanil 5μg/kg before propofol
Group1	Targeted controlled infusion	Alfentanil 2.5μg/kg before propofol
Group 3	Targeted controlled infusion	Alfentanil 2.5μg/kg two minutes before propofol
Group 5 Control	Normal saline	propofol alone
Group 4	Targeted controlled infusion	Alfentanil 5μg/kg two minutes before propofol
Group 5 Control	Targeted controlled infusion	propofol alone
Group 4	Propofol	Alfentanil 5μg/kg two minutes before propofol
Group1	Propofol	Alfentanil 2.5μg/kg before propofol
Group2	Propofol	Alfentanil 5μg/kg before propofol
Group 3	Alfentanil	Alfentanil 2.5μg/kg two minutes before propofol
Group 3	Propofol	Alfentanil 2.5μg/kg two minutes before propofol
Group 4	Alfentanil	Alfentanil 5μg/kg two minutes before propofol
Group 5 Control	Propofol	propofol alone

Primary Outcome Measures

Name	Time	Method
Induction Time, Time Period That Will be Required for Conscious Level to Reach OAAS-3	All participants wil be follow for the duration of bronchoscope room stay, an expect average of 2 hours	After the administration of Alfentanil and Propofol, the time period required to reach conscious level OAAS-3 will be recorded.
Propofol Dose Needed to Reach Conscious Level OAAS-3	All participants wil be follow for the duration of bronchoscope room stay, an expect average of 2 hours	After the administration of Alfentanil and Propofol, the Propofol dose needed to reach conscious level of observer assessment of alertness and sedation scale 3 (OAAS-3) will be recorded.
Effect Site Concentration When Conscious Level Reaches OAAS-3	All participants wil be follow for the duration of bronchoscope room stay, an expect average of 2 hours	After the administration of alfentanil and propofol, the effect site concentration was recorded at the time when the consciousness level reaches observer assessment of alertness and sedation scale 3 (OAAS-3). The effect site concentration is the concentration of drug propofol in brain calculated by TCI using Schnider model.

Secondary Outcome Measures

Name	Time	Method
Hypotension	All participants wil be follow for the duration of bronchoscope room stay, an expect average of 2 hours	Check the frequency of hypotension episode during induction, procedure and recovery time
Hypoxemia	All participants wil be follow for the duration of bronchoscope room stay, an expect average of 2 hours	Check the frequency of hypoxemia episode during induction, procedure, and recovery time