Alternative Sedation During Bronchoscopy (DEX)

• Minute ventilation [ Time Frame: About 2-3 hours during the bronchoscopy procedure only ] [ Designated as safety issue: Yes ]
  This will be assessed by calibrated respiratory inductance plethysmography
• Time to adequate sedation and procedure duration [ Time Frame: About 2-3 hours during the bronchoscopy procedure only ] [ Designated as safety issue: No ]
  Amount of time and duration of adequate sedation of the patient

• Cardiopulmonary stability [ Time Frame: About 2-3 hours during the bronchoscopy procedure only ] [ Designated as safety issue: Yes ]
  assessed by heart rate and pulse oximetry
• Patient compliance [ Time Frame: About 2-3 hours during the bronchoscopy procedure only ] [ Designated as safety issue: Yes ]
  assessed by the number of coughs per minute during the procedure
• Fentanyl/midazolam/benadryl consumption [ Time Frame: About 2-3 hours during the bronchoscopy procedure only ] [ Designated as safety issue: No ]
  The measurement of the amount of the standard of care sedation medications will be used during the procedure.
• Frequency of rescue from inadequate sedation [ Time Frame: About 2-3 hours during the bronchoscopy procedure only ] [ Designated as safety issue: Yes ]
  Measurement of time frame of inadequate sedation requiring intervention from the anesthesiologist.
• Patient and endoscopist satisfaction [ Time Frame: About 2-3 hours during the bronchoscopy procedure only ] [ Designated as safety issue: Yes ]
  assessed by Likert scale

This protocol hopes to determine whether the use of dexmedetomidine-ketamine can reduce the use of standard of care fentanyl-midazolam sedation during bronchoscopy. This may result in less respiratory depression while providing better compliance with the procedure.

All patients enrolled in the study will be undergoing bronchoscopy, which is typically performed with sedation. All procedural sedation carries some risk. Several features of the study may lower the risk of sedation relative to that of conventional sedation. An anesthesiologist will be present throughout the procedure. Continuous monitoring of respiration with RIP will be employed. Administration of sedation will be via a volumetric syringe pump. Benefits specific to dexmedetomidine-ketamine include the lack of respiratory depression and greater hemodynamic stability.

• Drug: dexmedetomidine and ketamine Study Medication
  Experimental Dexmedetomidine 200 µg in 50 ml Ketamine 30 mg Ketamine 200 mg in 20 ml Midazolam 10 mg + Fentanyl 250 µg + saline 5 ml Benadryl 25 mg
• Drug: placebo + Standard of Care of midazolam and fentanyl
  Control Saline 50 ml Midazolam 2 mg + Fentanyl 50 µg Saline 20 ml Midazolam 10 mg + Fentanyl 250 µg + saline 5 ml Benadryl 25 mg

• Placebo Comparator: Placebo + Standard of Care of midazolam and fentanyl
  1. Nebulized lidocaine 2% (maximum dose 200 mg) will be administered for 20 minutes.
  2. Following nebulization, syringe A (placebo) will be given at a rate of 1 µg/kg (based on a concentration of 4 µg/ml) for 10 minutes. Supplemental topical anesthesia will be administered by the pulmonologist during this time.
  3. After step 2, syringe B (midazolam 2 mg and fentanyl 50 µg) will be administered by the anesthesiologist. The infusion rate of syringe A (placebo) will be decreased to 0.7 µg/kg/hr. Syringe C (placebo) will be infused at 4 µg/kg/min (based on 10 mg/ml concentration)
  4. Boluses of 0.5 mg midazolam and 12.5 µg fentanyl will be administered by the pulmonologist from syringe D as needed for patient comfort. Syringe E (benadryl 25 mg) will be administered in entirety by the anesthesiologist after the 6th and 16th bolus of midazolam/fentanyl.
  Intervention: Drug: placebo + Standard of Care of midazolam and fentanyl
• Active Comparator: dexmedetomidine and ketamine + Standard of Care
  1. Nebulized lidocaine 2% (maximum dose 200 mg) will be administered for 20 minutes.
  2. Following nebulization, syringe A (dexmedetomidine) will be given at a rate of 1 µg/kg (based on a concentration of 4 µg/ml) for 10 minutes. Supplemental topical anesthesia will be administered by the pulmonologist during this time.
  3. After step 2, syringe B (ketamine 30 mg) will be administered by the anesthesiologist. The infusion rate of syringe A (dexmedetomidine) will be decreased to 0.7 µg/kg/hr. Syringe C (ketamine) will be infused at 4 µg/kg/min (based on 10 mg/ml concentration)
  4. Boluses of 0.5 mg midazolam and 12.5 µg fentanyl will be administered by the pulmonologist from syringe D as needed for patient comfort. Syringe E (benadryl 25 mg) will be administered in entirety by the anesthesiologist after the 6th and 16th bolus of midazolam/fentanyl.
  Intervention: Drug: dexmedetomidine and ketamine Study Medication

Inclusion Criteria:

• Adults over the age of 18 scheduled for elective flexible bronchoscopy in the endoscopy suite or OR of HUP

Exclusion Criteria:

• History of inability to complete bronchoscopy attributable to inadequate sedation
• Requiring more than 2 LPM supplemental oxygen to maintain SaO2 > 90%
• History of allergy to study medications
• Pregnancy
• A history of psychosis
• Any condition deemed likely by the pulmonologist or anesthesiologist to pose a significant risk due to elevation of blood pressure, including cerebral/aortic aneurysm, and or ischemic cardiovascular disease
• Bradydysrhythmia deemed significant by the anesthesiologist or pulmonologist
• A diagnosis of significant renal or hepatic impairment