Role of bronchoscopy in modern medical intensive care unit

Bronchoscopy during COVID-19 pandemic, ventilatory strategies and procedure measures

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has changed bronchoscopy practices worldwide. Bronchoscopy is a high-risk aerosol-generating procedure with a potential for direct SARS-CoV-2 exposure and hospital-acquired infection. Current guidelines about personal protective equipment and environment considerations represent key competencies to minimize droplets dispersion and reduce the risk of transmission. Different measures should be put in field based on setting, patient's clinical characteristics, urgency and indications of bronchoscopy. The use of this technique in SARS-CoV-2 patients is reported primarily for removal of airway plugs and for obtaining microbiological culture samples. In mechanically ventilated patients with SARS-CoV-2, bronchoscopy is commonly used to manage complications such as hemoptysis, atelectasis or lung collapse when prone positioning, physiotherapy or recruitment maneuvers have failed. Further indications are represented by assistance during percutaneous tracheostomy. Continuous positive airway pressure, non-invasive ventilation support and high flow nasal cannula oxygen are frequently used in patient affected by Coronavirus Disease-2019 (COVID-19): management of patients' airways and ventilation strategies differs from bronchoscopy indications, patient's clinical status and in course or required ventilatory support. Sedation is usually administered by the pulmonologist (performing the bronchoscopy) or by the anesthetist depending on the complexity of the procedure and the level of sedation required. Finally, elective bronchoscopy for diagnostic indications during COVID-19 pandemic should be carried on respecting rigid standards which allow to minimize potential viral transmission, independently from patient's COVID-19 status. This narrative review aims to evaluate the indications, procedural measures and ventilatory strategies of bronchoscopy performed in different settings during COVID-19 pandemic.

Bronchoscopy in intubated and non-intubated intensive care unit patients with respiratory failure

Bronchoscopy is one of the important tool for the pulmonary and critical care physicians to diagnose and treat various pulmonary conditions. It is increasingly being used by the intensivist due to its safety and portability. The utilization of bronchoscopy in the intensive care unit (ICU) has made the diagnosis and treatment of many conditions more feasible to intensivists. Sedation, topical or intravenous, usually helps better tolerate the procedure. However, the risks and benefits of bronchoscopy should be carefully considered in critically ill patients. The hypoxic patients in ICU pose a challenge as hypoxemia is one of the known complications of bronchoscopy, and this risk is exacerbated in patients with hypoxic respiratory failure. Bronchoscopy is relatively contraindicated in patients with severe hypoxemia and coagulopathy. However, bronchoscopy in hypoxic patients can have diagnostic as well as therapeutic implications. In patients with hypoxic respiratory failure, the use of non-invasive ventilation (NIV) during bronchoscopy has been shown to reduce the risk of intubation. On the other hand, bronchoscopy in mechanically ventilated patients is not contraindicated and has been widely used. Staying focused, monitoring vital signs closely, limiting the scope time in the airway, and understanding patient’s physiology may help decrease risk of complications. In this review, we discuss indications, techniques, complications, and yield associated with bronchoscopy in critically ill hypoxic patients.

Recovery process and determinants of adverse event occurrence in bronchoscopic procedures performed under general anaesthesia

OBJECTIVE

Regarding the fact that rigid bronchoscopy is generally performed under general anaesthesia and this patient subgroup is remarkably morbid, encountering procedure and/or anaesthesia related complications are highly likely. Here, we aimed to assess factors influencing recovery and detect possible determinants of adverse event occurrence during these operations performed in a tertiary referral centre.

METHODS

Eighty-one consecutive ASA I-IV patients were recruited for this investigation. In the operating theatre after induction of anaesthesia and advancement of the device, maintenance was provided with total intravenous anaesthesia. Neuromuscular blockage was invariably administered, and patients were ventilated manually. In addition to preoperative demographic and procedural characteristics, perioperative hemodynamic variables, recovery times and observed adverse events were noted.

RESULTS

Basic demographic properties, ASA and Mallampati scores, and procedure specific variables as lesion localization, lesion and procedure type were comparable among groups assembled with reference to event occurrence. Patients who had experienced adverse event had higher heart rates. Recovery times were comparable between Event (-) and Event (+) groups. Relationship of recovery process were individually tested with all variables and only lesion type was detected to have an effect on respiration and extubation times. Among all parameters only procedural time seemed to be associated with adverse event occurrence (mins, 22.9 ± 11.9 vs 41.6 ± 28.8, P < .001).

CONCLUSION

Recovery times related with return of spontaneous respiration were significantly lower in procedures performed for treatment of tumoral diseases in this study and procedure length was determined to be the ultimate factor which had an impact on adverse event occurrence.

Therapeutic bronchoscopy vs. standard of care in acute respiratory failure: a systematic review

BACKGROUND

We aimed to assess patient-important benefits and harms of therapeutic bronchoscopy vs. standard of care (no bronchoscopy) in critically ill patients with acute respiratory failure (ARF).

METHODS

We conducted a systematic review with meta-analysis and trial sequential analysis (TSA) according to the Cochrane Handbook and GRADE methodology, including a predefined protocol (PROSPERO no. CRD42016046235). We included randomized clinical trials (RCTs) comparing therapeutic bronchoscopy to standard of care in critically ill patients with ARF. Two reviewers independently assessed trials for inclusion, extracted data and assessed risk of bias. Risk ratios (RR) with 95% confidence intervals (CI) were estimated by conventional meta-analysis. The risk of random errors was assessed by TSA. Exclusively patient-important outcomes were evaluated.

RESULTS

We included five trials (n = 212); all were judged as having high risk of bias. There was no difference in all-cause mortality between therapeutic bronchoscopy and standard of care (TSA adjusted RR 0.39; 95% CI 0.14 to 1.07; I² 0%), and only 3% of the required information size had been accrued. There was no difference in ICU length of stay. A shorter duration of mechanical ventilation was suggested by conventional meta-analysis, however TSA highlighted that only 42% of the required information size had been accrued, indicating high risk of random errors. No trials reported data on adverse events, hospital length of stay, quality of life or performance status.

CONCLUSIONS

The quantity and quality of evidence supporting therapeutic bronchoscopy in critically ill patients with ARF is very low with no firm evidence for benefit or harm.

Full Airway Drainage by Fiber Bronchoscopy Through Artificial Airway in the Treatment of Occult Traumatic Atelectasis

The objective of this study is to investigate the effects of full airway drainage by fiber bronchoscopy through artificial airway in the treatment of traumatic atelectasis with occult manifestations. From May 2006 to May 2011, 40 cases of occult traumatic atelectasis were enrolled into our prospective study. Group A (n = 18) received drainage by nasal bronchoscope; group B underwent airway drainage by fiber bronchoscopy through artificial airway (n = 22). The effects of treatment were evaluated by the incidence of adult respiratory distress syndrome (ARDS), lung abscess, and the average length of hospital stay. Compared with nasal fiber-optic treatment, airway drainage by fiber bronchoscopy through artificial airway reduced the incidence of ARDS (p = 0.013) and lung abscess (p = 0.062) and shortened the mean length of stay (p = 0.018). Making the decision to create an artificial airway timely and carry out lung lavage by fiber bronchoscopy through artificial airway played a significant role in the treatment of occult traumatic atelectasis.

Safety of research bronchoscopy in critically ill patients

OBJECTIVE

Bronchoscopy and bronchoalveolar lavage (BAL) are common procedures in intensive care units; however, no contemporaneous safety and outcomes data have been reported, particularly for critically ill patients.

DESIGN

This is a retrospective analysis of prospectively collected data from teaching hospital adult intensive care units.

INTERVENTIONS

One hundred mechanically ventilated patients with severe sepsis, septic shock, acute lung injury (ALI), and/or acute respiratory distress syndrome underwent bronchoscopy with unilateral BAL. Data collected included demographics, presence of sepsis or ALI, Pao2 to Fio2 ratio, positive end-expiratory pressure, Acute Physiology and Chronic Health Evaluation score, Sequential Organ Failure Assessment score, and peri- or postprocedural complications.

RESULTS

Men comprised 51% of the patients; 81% of the patients were black, and 15% were white. The mean age was 52 (SD, ±16) years. The mean Acute Physiology and Chronic Health Evaluation score was 22 (±7.5), whereas the median Sequential Organ Failure Assessment score was 9 (interquartile range, 5-12). Ten patients (10%) had complications during or immediately after the procedure. Hypoxemia during or immediately after the BAL was the most common complication. Ninety percent of the complications were related to transient hypoxemia, whereas bradycardia and hypotension each occurred in 1 patient. Age, female sex, and higher positive end-expiratory pressure were associated with complications.

CONCLUSIONS

Bronchoscopy with BAL in critically ill patients with sepsis and ALI is well tolerated with low risk of complications, primarily related to manageable hypoxemia.

Indications and Efficacy of Fiberoptic Bronchoscopy in the ICU: Have They Changed Since Its Introduction in Clinical Practice?

Purpose. We describe characteristics, utility, and safety of fiberoptic bronchoscopy (FOB) in an intensive care unit (ICU). Methods. Prospective and descriptive cohort of patients admitted to a respiratory ICU from March 2010 to June 2012. Results. A total of 102 FOBs were performed in 84 patients among 580 patients that were admitted to the ICU. Mean age was 48±17 years. FOB was useful in 65% of diagnostic procedures and 83% of therapeutic procedures, with an overall utility of 75%. Indications and utility according to indication were pneumonia in 31 cases, utility of 52%; percutaneous tracheostomy guidance in 26 cases, utility of 100%; atelectasis in 25 cases, utility of 76%; airway exploration in 16 cases, utility of 75%; hemoptysis in two cases, utility of 100%; and difficult airway intubation in two cases, utility of 100%. A decrease in oxygen saturation (SpO2) of >5% during FOB was present in 65% of cases, and other minor complications were present in 3.9% of cases. Conclusions. Reasons for performing FOB in the ICU have remained relatively stable over time with the exception of the addition of percutaneous tracheostomy guidance. Our series documents current indications and also the utility and safety of this procedure.

Safety of performing fiberoptic bronchoscopy in critically ill hypoxemic patients with acute respiratory failure

BACKGROUND

The safety of fiberoptic bronchoscopy (FOB) in nonintubated critically ill patients with acute respiratory failure has not been extensively evaluated. We aimed to measure the incidence of intubation and the need to increase ventilatory support following FOB and to identify predictive factors for this event.

METHODS

A prospective multicenter observational study was carried out in eight French adult intensive care units. The study included 169 FOB performed in patients with a PaO(2)/FiO(2) ratio ≤ 300. The main end-point was intubation rate. The secondary end-point was rate of increased ventilatory support defined as an increase in oxygen requirement >50 %, the need to start noninvasive positive pressure ventilation (NI-PPV) or increase NI-PPV support.

RESULTS

Within 24 h, an increase in ventilatory support was required following 59 bronchoscopies (35 %), of which 25 (15 %) led to endotracheal intubation. The existence of chronic obstructive pulmonary disease (COPD; OR 5.2, 95 % CI 1.6-17.8; p = 0.007) or immunosuppression (OR 5.4, 95 % CI 1.7-17.2; p = 0.004] were significantly associated with the need for intubation in the multivariable analysis. None of the baseline physiological parameters including the PaO(2)/FiO(2) ratio was associated with intubation.

CONCLUSIONS

Bronchoscopy is often followed by an increase in ventilatory support in hypoxemic critically ill patients, but less frequently by the need for intubation. COPD and immunosuppression are associated with the need for invasive ventilation in the 24 h following bronchoscopy.

Feasibility and safety of transglottic bronchoscopy in mechanically ventilated sheep

PURPOSE

Although bronchoscopy can be safely performed through endotracheal tube in most intubated critically ill patients, sometimes it could lead to complications such as hypoxia and high airway pressures. Theoretically, transglottic bronchoscopy (TGB) does not interfere with mechanical ventilation and could avoid these complications. In a two-period crossover study, we compared this technique with trans-endotracheal tube bronchoscopy (TEB) in normal anesthetized sheep.

METHODS

In five sheep, we did TGB first. The bronchoscope was introduced through the nasal nares and passed into the trachea via space between endotracheal tube and vocal folds. Heart rate, V(T), P(peak), and O(2) saturation were recorded. One week later, we did TEB. In another five sheep, we did TEB first and TGB later.

RESULTS

P(peak) increased and V(T) and O(2) saturation decreased during TEB (53.2 ± 5.7 vs. 27.6 ± 0.6, P = 0.002; 210 ± 32 vs. 285 ± 26, P = 0.002; 94.3 ± 1.3 vs. 97.5% ± 0.5, P = 0.041, respectively), but not during TGB. The only statistically significant abnormal finding during TGB was a mild tachycardia (96.7 ± 5.7 vs. 94.7 ± 5.5, P = 0.034).

CONCLUSION

Although TGB is time consuming and less convenient than TEB, it has minimal interference with mechanical ventilation. Expertise with this technique could be useful in patients with anticipated significant hypoxia and high airway pressures during bronchoscopy.

Evaluation of a 24-hour emergency bronchoscopy service in a tertiary care hospital

BACKGROUND

Flexible bronchoscopy has become an important diagnostic and therapeutic tool for the management of patients with various diseases of the chest. Availability of a 24-hour bronchoscopy service equipped with experienced personnel is becoming increasingly important especially for intensive care patients. However, such services have been implemented only in a few medical centres. The aim of this study was to evaluate the usage of a 24-hour emergency service in a large university hospital with a 1 year prospective analysis of emergency bronchoscopy service in a tertiary care centre.

METHODS

Frequencies, indications and efficiency of therapeutic interventions were evaluated after each bronchoscopy using a specially designed questionnaire. All bronchoscopies were performed as emergency procedures out of operational schedule. A total of 614 emergency bronchoscopies were performed, 88% of them in intensive care units.

RESULTS

The vast majority (84.5%) of the procedures were necessary for therapeutic interventions; that is, atelectasis, airway secretion, aspiration or bronchopulmonary bleeding. According to prespecified criteria, 37.6% (n = 195) of therapeutic procedures were assessed as 'very helpful' and 3.9% (n = 20) as 'life saving'. Diagnostic bronchoscopies were performed mainly to collect airway material for microbiological evaluations in immunocompromised patients. In these cases, the diagnostic yield was approximately 50%.

CONCLUSION

The availability of a 24-hour bronchoscopy service has been found to improve patient care and was occasionally considered life saving. Thus, comparable services should be made more widely available.

Use of an ultrathin bronchoscope in the assessment of central airway obstruction

STUDY OBJECTIVE

To assess the utility of an ultrathin bronchoscope (UB) in the assessment of central airway obstruction (CAO).

DESIGN

Prospective evaluation

SETTING

Tygerberg Hospital, a tertiary teaching hospital.

PATIENTS

Consecutive patients referred to the Lung Unit with CAO.

INTERVENTIONS

Fiberoptic bronchoscopy (FOB) was performed with a prototype UB (Olympus BF XP40; Olympus Europe; Hamburg, Germany; outer diameter, 2.8 mm; working channel, 1.2 mm). The UB was used whenever a standard bronchoscope (SB) could not pass the obstruction or could not be tolerated by the patient.

MEASUREMENTS AND RESULTS

Data relating to indication and performance of FOB, patient demographics, utility in establishing a diagnosis, and planning definitive management were documented. Twenty-four patients (17 men; mean age, 46 years) were studied. Twelve patients (50%) had malignant CAO, 8 patients (33%) had benign tracheal stenosis, 3 patients (12.5%) had stent occlusion, and 1 patient (4%) had bilateral vocal cord paralysis. In 42% of patients, an initial attempt at passing the obstruction with an SB had failed. Vocal cords or trachea were involved in 62% of patients. The mean luminal occlusion was 84% of the total airway lumen (range, 50 to 100%). One complication (desaturation) led to early termination of FOB. In all but three patients with complete obstruction, the UB was able to pass the CAO and allowed assessment of the obstruction and the distal airways (87%).

CONCLUSION

UB-FOB was useful and safe in the assessment of patients with CAO from both benign and malignant disease. It aided in establishing a diagnosis and/or planning of definitive management in all patients examined.

Fibrobroncoscopia en el niño con ventilación mecánica

Fiberoptic bronchoscopy can be performed at the patient's bedside. This technique allows direct visualization of the upper and lower airways up to the segmental and subsegmental bronchi. Its most frequent indications are airway examination ot evaluate damage produced by toxins or the endotracheal tube, patency of the endotracheal tube and extubation failure. It is also used to obtain microbiological samples, facilitate intubation when difficult, aspirate airway sections or mucus plugs, perform bronchoalveolar lavage and administer drugs. With prior preparation, adequate monitoring and sedation, material according to the size of the patient and correct techniques, there are few complications. However, the procedure can produce trauma and obstruction of the airway, bronchial hemorrhage, barotrauma, loss of alveolar recruitment, bronchospasm, hypoxemia, bradycardia, and bronchopulmonary infection.