Evaluation of a Disposable Flexible Bronchoscope, aScope IV

Flexible bronchoscopes are typically reusable and therefore need high level disinfection to prevent inadvertent spread of microbial pathogens from patient to patient. The process of disinfection is time consuming and expensive. Moreover, a bronchoscope being processed may not be readily available for another patient. One solution to this problem was to use a single use disposable sheath that covers a flexible bronchoscope protecting all surfaces of the bronchoscope.(Colt, Beamis, Harrell, \& Mathur, 2000). Another way to eliminate potential hazards with a reusable bronchoscope is the use of a disposable bronchoscope. Such a disposable bronchoscope has been developed (Ambu aScope, Ambu, Glen Burnie, MD) and has been used successfully for intubations in manikins(Scutt et al., 2011) and patients. (Kristensen \& Fredensborg, 2013; Pujol, López, \& Valero, 2010; Tvede, Kristensen, \& Nyhus-Andreasen, 2012). Further advancement in the imaging and handling of this disposable flexible bronchoscope now allows for the purpose of bronchoscopy and broncho-alveolar lavage in critically ill patients with pulmonary compromise. (FDA approval: 05-11-2013 date)

The aim of the study is to compare image clarity, suction capacity, and handling performance of a reusable flexible bronchoscope to the disposable flexible bronchoscope. In addition, the investigators intend to perform a cost analysis.

Description

Patients will be monitored by standard NIBP or invasive arterial lines, ECG and oxygen saturation. All patients are intubated due to their respiratory insufficiency or for airway protection. Patients will be anesthetized for the procedure. Anesthesia will be induced with versed 2mg, fentanyl 100 µg and paralyzed with 0.1mg/kg vecuronium. Anesthesia will be maintained with propofol infusion 50-150 µg/kg/min.

Study Procedures All patients will be under general anesthesia. Standard monitoring will be applied. This includes a blood pressure cuff or an arterial line, EKG and a pulse-oximeter. Patients will receive 2 mg/kg propofol, 1µg/kg fentanyl and 0.1mg/kg vecuronium for the procedure. After induction of anesthesia the FiO2 will be turned to 1.0 and a bronchoscopy adaptor will be interposed in the breathing circuit next to the endotracheal tube. Patients will be randomized to receiving either the non-disposable bronchoscope (Storz 8402 2x, El Segundo, CA) or the single use aScope 3 first. After randomization, bronchoscopy will be started with an inspection of the trachea and carina. Next the right lung bronchial tree will be inspected systematically beginning with the right upper lobe, following with the right middle lobe and finishing with the right lower lobe. All segmental bronchi will be inspected and cleaned by suction as deemed necessary. The bronchoscope will then be removed from the bronchial tree and rinsed with saline Subsequently, the bronchoscope will be re-inserted and advanced to the basal segmental bronchi of the right lower lobe. The tip of the bronchoscope will be brought into wedge position in one of the basal segments for broncho-alveolar lavage (BAL). A saline flush of 20 ml will be administered. The flow of saline will be observed at the distal tip of the bronchoscope. After 10 seconds of maintaining a wedge position, gentle suction will be applied to collect the lavage specimen in the collection trap. This step will be repeated 4 more times (total of 80ml) to obtain an adequate specimen. The same procedure will be repeated on the left lung using the alternate bronchoscope according to randomization. At the end of the procedure, a chest radiograph will be obtained to rule out pneumothorax.

Measurements

Before starting the procedure the set up time of each bronchoscope will be recorded. The view, image, and light of each bronchoscope will be assessed, then the inspection of the upper lobe segmental bronchi will be conducted. The time of lavage and suctioning until no more specimen can be collected will be measured. The volume of the obtained specimen will be measured. The specimen will be evaluated by a blinded observer after the procedure is completed.(clear fluids, mucous secretions, viscous secretions, pus, blood etc). The blinded observer will evaluate the quality and quanity of the sample for obtaining cultures.The blinded observer will be an attending or resident from the infectious disease department.

The overall ease of handling will be rated directly after the procedure by the investigator. All bronchoscopies will be taped and view-clarity, image and light-brightness will be assessed by a second blinded observer. This blinder observer can be another investigator not present during the procedure or an internist who was not present and is part of the study team.

All assessments will be performed using a VAS scale of 0 to 10 cm as shown below. The investigator will mark directly on the scale.

We will only enroll patients who were admitted to a critical care unit at the University of Louisville and who are intubated.

Eligibility Criteria:
Inclusion Criteria:

1. Adult 18 years old and older
2. Capable of giving informed consent or have an acceptable surrogate capable of giving legally authorized consent on the subject's behalf.
3. Indication of a diagnostic and or therapeutic bronchoscopy as determined by the attending critical care physician
4. Being cared for in the critical care units at the U of L Hospital

Exclusion Criteria:

1) Patient is moribund and a bronchoscopy is very unlikely to reduce impending mortality or can avert death