Non-anesthesiologist-administered Propofol During the Flexible Bronchoscopy

Flexible bronchoscopy (FB) is a fundamental procedure for the diagnosis and treatment of respiratory diseases. Although midazolam is the recommended sedative agent by most guidelines, propofol has gained popularity due a short recovery time, however, evidence to propofol use for sedation during FB is scarce. There is little evidence about transcutaneous CO2 pressure (PtcCO2) behavior among patients sedated with propofol when it is administered by non-anesthesiologist and in combination with intravenous opioids for analgesia and cough inhibition.

The investigators performed a randomized controlled trial to determine whether non-anesthesiology-administered balanced-sedation with propofol was related to high values of values of PtcCO2 compared with guideline-based sedation (midazolam and opioid). The investigators included data from outpatients 18 years or older with an indication for FB in a university hospital in northern of Mexico. Secondary outcomes were recuperation time, patient satisfaction and adverse effects.

The investigators prospectively included ambulatory patients aged \> 18 years with an indication for flexible bronchoscopy. Bronchoscopic procedures were performed by residents of Respiratory and Critical Care Medicine subspecialty under the supervision of an attendant professor in a university-tertiary-referral center in northern Mexico. Patients with tracheostomy, known allergy to drugs used during procedural sedation, inability to answer the satisfaction questionnaires, psychiatric illness, pregnancy, or with ASA class IV or V, were excluded.

Patients were randomly assigned to receive sedation with midazolam or propofol. In the group of midazolam the initial dose was 0.05 mg/kg and in propofol group, the starting dose was 0.1 mg /kg. Additional doses of the corresponding drug (2 mg of midazolam or 10 mg of propofol) were allowed to reach a score level of 3 to 4 in the Observer´s assessment of alertness/ sedation scale. All patients received nalbuphine in a starting dose of 2 mg with additional doses of 1 mg if it was necessary. Prior to insertion of the bronchoscope, lidocaine spray was applied to the nasal mucosa and pharynx for bronchoscope nasal insertion, and only in the pharynx for bronchoscope oral insertion. Topical lidocaine was applied using the spray-as-you-go technique, at a maximum dose of 7 mg/kg.

In both groups, transcutaneous CO2 measurement was carried out with the system SenTec digital monitoring (Artemis Medical, Kent, London) by applying a Stow-Severinghaus (V-Sign sensor) type sensor in the ear lobe. All patients received supplementary oxygen and were monitored with intermittent non-invasive blood pressure measurements every 3 min and with continuous EKG and SO2 surveillance.

The assessment of the state of residual sedation was performed with the Aldrete scale at five, 10 and 15 minutes after complete FB. At the time of discharge from the bronchoscopy suite, a satisfaction questionnaire was applied to patients.

Sedation and analgesia were prescribed by the resident responsible for conducting FB without the support of specialists in anesthesiology. One collaborator blinded to the study group to which each patient belonged recorded all data derived from the procedure. The Bronchoscopist was blinded to PtcCO2 values.

Eligibility Criteria:
Inclusion Criteria:

* Ambulatory patients aged \> 18 years with an indication for flexible bronchoscopy.

Exclusion Criteria:

* tracheostomy
* known allergy to drugs used during procedural sedation
* inability to answer the satisfaction questionnaires
* psychiatric illness, pregnancy
* ASA class IV or V