Bronchoscopy: The Past, the Present, and the Future

Pre-operative nasal probe tests with adrenaline and lidocaine ease insertion during flexible bronchoscopy and reduce post-operative bleeding: a randomized controlled trial

BACKGROUND

Nasal insertion is the preferred method for non-intubated patients in flexible bronchoscopy; however, the relatively narrow nasal cavity results in difficulties related to bronchoscope insertion. This study aimed to investigate whether pre-operative nasal probe tests could reduce the time to pass the glottis, improve the first-pass success rate and patients' tolerance, and reduce postoperative bleeding.

METHODS

This three-arm prospective randomized controlled trial was conducted in a tertiary hospital between May and October 2020. Three hundred patients requiring diagnosis and treatment using flexible bronchoscopy were randomly allocated to three groups: control group, simple cotton bud detection group (CD group), and adrenaline + lidocaine detection group (AD group). The primary outcome was the time to pass the glottis. Secondary outcomes included the first-pass success rate, the patients' tolerance scores, and post-operative bleeding. One-way analysis of variance, Kruskal-Wallis H test, Chi-squared test, Fisher's exact test, and Bonferroni's multiple comparison tests were used in this study.

RESULTS

In total, 189 men and 111 women were enrolled in this study, with a mean age of 55.72 ± 12.86 years. The insertion time was significantly shorter in the AD group than in the control group (18.00 s [12.00-26.50 s] vs . 24.00 s [14.50-45.50 s], P = 0.005). Both the AD (99% vs . 83%, χ2 = 15.62, P < 0.001) and CD groups (94% vs . 83%, χ2 = 5.94, P = 0.015) had a significantly higher first-pass success rate than the control group. Compared with the control group, post-operative bleeding (1% vs . 13%, χ2 = 11.06, P < 0.001) was significantly lower in the AD group. However, no significant difference was found in the patients' tolerance scores.

CONCLUSIONS

Pre-operative nasal cavity probe tests especially with adrenaline and lidocaine during flexible bronchoscopy can significantly reduce the time to pass the glottis, improve the first-pass success rate, and reduce post-operative nasal bleeding. Pre-operative nasal probe tests are recommended as a time-saving procedure for patients undergoing flexible bronchoscopy.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR), ChiCTR2000032668; http://www.chictr.org.cn/showprojen.aspx?proj=53321 .

Portable electronic bronchoscopy for clinical application: a multi-institutional randomized instrument validation study

OBJECTIVE

Electronic bronchoscopy is routinely used for the diagnosis and treatment of lung and bronchial disorders. However, the devices used are normally large and costly. Here, we evaluated the clinical effectiveness of a portable electronic bronchoscope produced by Zhejiang UE Medical Corp., the UE-EB.

METHODS

We conducted a multi-institutional, randomized, single-blind, non-inferiority and parallel-group controlled clinical trial. Participants were randomly assigned 1:1 to the experimental group or control group. The primary indicator was the effectiveness of the device. Safety indicators were assessed from enrollment to 3 days after the operation.

RESULTS

The UE-EB had good consistency between groups during the procedure, and the effective rate was 100.00% in both groups. The difference value (95% confidence interval) between the two groups was 0.00% (-5.45%, 5.45%), and the lower limit was greater than -10% (negative non-inferiority margin). There was also no difference between the two groups in terms safety indicators.

CONCLUSIONS

The portable electronic bronchoscope described in this study showed reliable effectiveness and safety. This device is worth promoting and applying in clinical practice.Research registry number: ZXLB20200295 (Zhejiang Medical Products Administration, China).

Efficacy and Safety of HSK3486 for Anesthesia/Sedation in Patients Undergoing Fiberoptic Bronchoscopy: A Multicenter, Double-Blind, Propofol-Controlled, Randomized, Phase 3 Study

BACKGROUND

Fiberoptic bronchoscopy is a complex procedure with the need for sufficient patient anesthesia/sedation while maintaining safety. This trial aimed to evaluate the efficacy, safety, and pharmacokinetics of HSK3486 during fiberoptic bronchoscopy.

METHODS

This multicenter, double-blind, randomized, non-inferiority, parallel-group phase 3 trial was conducted in patients who underwent fiberoptic bronchoscopy. Patients randomly received HSK3486 0.4 mg/kg (N = 134) or propofol 2.0 mg/kg (N = 133). The primary efficacy endpoint was the successful rate of fiberoptic bronchoscopy, and secondary efficacy endpoints included successful induction of anesthesia/sedation, duration, time to being fully alert, and time to patient discharge. Safety assessments and drug concentrations were also measured.

RESULTS

A total of 267 patients completed fiberoptic bronchoscopy, with a success rate of 100% and a 95% confidence interval of - 2.8 to 2.8% for the difference between the groups, which met the predesigned criteria of > - 8%, confirming the non-inferiority of anesthesia/sedation produced by HSK3486 compared to propofol. Among the secondary efficacy endpoints, only time to full alertness (median 8.50 vs. 6.00 min, P = 0.012) and time to discharge (median 13.00 vs. 9.87 min, P = 0.002) were slightly longer in the HSK3486 group. The incidence of adverse events was significant lower in the HSK3486 group (52.6 vs. 76.5%, P < 0.001) mainly because of less pain on injection (4.4 vs. 39.4%, P < 0.001) compared to the propofol group. HSK3486 had a similar terminal elimination half-life as propofol.

CONCLUSIONS

HSK3486 exhibited non-inferiority anesthesia/sedation compared to propofol in patients undergoing fiberoptic bronchoscopy, and had a good safety profile with a lower incidence of pain on injection.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT04111159, registered on 1 October 2019.

Multi-material three dimensional printed models for simulation of bronchoscopy

Background

Bronchoscopy involves exploration of a three-dimensional (3D) bronchial tree environment using just two-dimensional (2D) images, visual cues and haptic feedback. Sound knowledge and understanding of tracheobronchial anatomy as well as ample training experience is mandatory for technical mastery. Although simulated modalities facilitate safe training for inexperienced operators, current commercial training models are expensive or deficient in anatomical accuracy, clinical fidelity and patient representation. The advent of Three-dimensional (3D) printing technology may resolve the current limitations with commercial simulators. The purpose of this report is to develop and test the novel multi-material three-dimensional (3D) printed airway models for bronchoscopy simulation.

Methods

Using material jetting 3D printing and polymer amalgamation, human airway models were created from anonymized human thoracic computed tomography images from three patients: one normal, a second with a tumour obstructing the right main bronchus and third with a goitre causing external tracheal compression. We validated their efficacy as airway trainers by expert bronchoscopists. Recruited study participants performed bronchoscopy on the 3D printed airway models and then completed a standardized evaluation questionnaire.

Results

The models are flexible, life size, anatomically accurate and patient specific. Five expert respiratory physicians participated in validation of the airway models. All the participants agreed that the models were suitable for training bronchoscopic anatomy and access. Participants suggested further refinement of colour and texture of the internal surface of the airways. Most respondents felt that the models are suitable simulators for tracheal pathology, have a learning value and recommend it to others for use in training.

Conclusion

Using material jetting 3D printing to create patient-specific anatomical models is a promising modality of simulation training. Our results support further evaluation of the printed airway model as a bronchoscopic trainer, and suggest that pathological airways may be simulated using this technique.

Bronchoscopy: Diagnostic and Therapeutic for Non-Small Cell Lung Cancer

The bronchoscope has gone through much advancement from its origin as a thin metal tube. It has become a highly sophisticated tool for clinicians. Both rigid and the flexible bronchoscopes are invaluable in the diagnosis and treatment of non-small cell lung cancer. Treatment of this disease process hinges on accurate diagnosis and lymph node staging. Technologies, such as endobronchial ultrasound, navigational bronchoscopy, and autofluorescence, have improved efficacy of endobronchial diagnosis and sample collection. If a patient is not a candidate for surgery and has a complication from a centrally located mass, the bronchoscope has been used to deliver palliative therapies.

Evaluation of a flexible bronchoscope prototype designed for bronchoscopy during mechanical ventilation: a proof-of-concept study

Bronchoscopy during mechanical ventilation of patients' lungs significantly affects ventilation because of partial obstruction of the tracheal tube, and may thus be omitted in the most severely ill patients. It has not previously been possible to reduce the external diameter of the bronchoscope without reducing the diameter of the suction channel, thus reducing the suctioning capacity of the device. We believed that a better-designed bronchoscope could improve the safety of bronchoscopy in patients whose lungs were ventilated. We designed a flexible bronchoscope prototype with a drumstick-shaped head consisting of a long, thin proximal portion; a short and large distal portion for camera docking; and a large suction channel throughout the length of the device. The aims of our study were to test the impact of our prototype on mechanical ventilation when inserted into the tracheal tube, and to assess suctioning capacity. We first tested the efficiency of the suction channel, and demonstrated that the suction flow of the prototype was similar to that of conventional adult bronchoscopes. We next evaluated the consequences of bronchoscopy when using the prototype on minute ventilation and intrathoracic pressures during mechanical ventilation: firstly, in vitro using a breathing simulator; and secondly, in vivo using a porcine model of pulmonary ventilation. The insertion of adult bronchoscopes into the tracheal tube immediately impaired the protective ventilation strategy employed, whereas the prototype preserved it. For the first time, we have developed an innovative flexible bronchoscope designed for bronchoscopy during invasive mechanical ventilation, that both preserved the protective ventilation strategy, and enabled efficient suction flow.

Utility of Cell-Block of Bronchial Washings in Diagnosis of Lung Cancer- A Comparative Analysis with Conventional Smear Cytology

INTRODUCTION

Bronchoscopy is a safe & effective means of diagnosing bronchogenic carcinoma with a varying diagnostic yield of different bronchoscopic procedures. Cell-Block (CB) preparation of cytology specimen has been shown to increase the diagnostic yield further. To the authors' knowledge, the diagnostic value of CB as an adjunct to conventional smear cytology (CS) of bronchial washing specimens in the detection of bronchogenic carcinoma has not been well evaluated.

AIM

The present study was aimed to evaluate the diagnostic utility of CB of bronchial washings when compared with CS.

MATERIALS AND METHODS

A total of 104 patients of suspected bronchogenic carcinoma were subjected to bronchoscopy as per British Thoracic Society (BTS) protocol. Bronchial biopsy, brushings and washings were collected. Smears were prepared immediately of bronchial washings and another aliquot was subjected to CB preparation and further processing by paraffin embedding and H&E staining.

RESULTS

Out of 104 patients, 92 were diagnosed by bronchoscopy with a cumulative diagnostic yield of all sampling techniques being 88.46%. Yield of CB of bronchial washings (44.23%) was higher than Bronchial washings - conventional smears (36.53%). CB detected additional 8 cases of malignancy where corresponding bronchial washings-conventional smears were negative. Exclusive diagnosis by CB was obtained in 2 cases. Brushings and biopsy confirmed malignancy in 49.03% and 57.69% cases.

CONCLUSION

CB of bronchial washings had a higher yield as compared to corresponding conventional smears. Increase in yield was also noted when CB of bronchial washings was combined with biopsy and compared to bronchial washings- conventional smears combined with biopsy. In limited resource settings, CB preparation is a simple method that increases diagnostic yield of flexible bronchoscopy, is cost effective & hence can be routinely used. The immunohistochemical and molecular studies are possible with CB only, which is a distinct advantage over conventional smears of bronchial washings.

Advances in diagnostic interventional pulmonology

The recent advances in diagnostic pulmonary procedures have revolutionized the evaluation of abnormal thoracic findings including lung nodules and masses, mediastinal lymphadenopathy, and pleural diseases. Bronchoscopies with endobronchial ultrasonography and electromagnetic navigation are examples of new technology that has significantly improved the specificity and sensitivity of these procedures in diagnosis and staging of lung cancer without the need for more invasive procedures. This report describes the different diagnostic pulmonary interventions providing a description of the procedures, their indications, diagnostic yield and drawback.

Operative rigid bronchoscopy: indications, basic techniques and results

Palliative airway treatments are essential to improve quality and length of life in lung cancer patients with central airway obstruction. Rigid bronchoscopy has proved to be an excellent tool to provide airway access and control in this cohort of patients. The main indication for rigid bronchoscopy in adult bronchology remains central airway obstruction due to neoplastic or non-neoplastic disease. We routinely use negative pressure ventilation (NPV) under general anaesthesia to prevent intraoperative apnoea and respiratory acidosis. This procedure allows opioid sparing, a shorter recovery time and avoids manually assisted ventilation, thereby reducing the amount of oxygen needed, while maintaining optimal surgical conditions. The major indication for NPV rigid bronchoscopy at our institution has been airway obstruction by neoplastic tracheobronchial tissue, mainly treated by laser-assisted mechanical dissection. When strictly necessary, we use silicone stents for neoplastic or cicatricial strictures, reserving metal stents to cover tracheo-oesophageal fistulae. NPV rigid bronchoscopy is an excellent tool for the endoscopic treatment of locally advanced tumours of the lung, especially when patients have exhausted the conventional therapeutic resources. Laser-assisted mechanical resection and stent placement are the most effective procedures for preserving quality of life in patients with advanced stage cancer.

Flexible bronchoscopy

Although bronchoscopy technology continues to evolve at a fairly rapid pace, basic procedures, such as bronchoalveolar lavage, transbronchial lung biopsy, and transbronchial needle aspiration, continue to play a paramount role in the diagnosis of bronchopulmonary diseases. Pulmonologists should be trained in these basic bronchoscopic procedures.