Isolation of the lung: Double-lumen tubes and endobronchial blockers

Protecting the non-operative lobe/s of the operative lung can reduce the pneumonia incidence after thoracoscopic lobectomy: a randomised controlled trial

Lung isolation usually refers to the isolation of the operative from the non-operative lung without isolating the non-operative lobe(s) of the operative lung. We aimed to evaluate whether protecting the non-operative lobe of the operative lung using a double-bronchial blocker (DBB) with continuous positive airway pressure (CPAP) could reduce the incidence of postoperative pneumonia. Eighty patients were randomly divided into two groups (n = 40 each): the DBB with CPAP (Group DBB) and routine bronchial blocker (Group BB) groups. In Group DBB, a 7-Fr BB was placed in the middle bronchus of the right lung for right lung surgery and in the inferior lobar bronchus of the left lung for left lung surgery. Further, a 9-Fr BB was placed in the main bronchus of the operative lung. In Group BB, routine BB placement was performed on the main bronchus on the surgical side. The primary endpoint was the postoperative pneumonia incidence. Compared with Group BB, Group DBB had a significantly lower postoperative pneumonia incidence in the operative (27.5% vs 5%, P = 0.013) and non-operative lung (40% vs 15%) on postoperative day 1. Compared with routine BB use for thoracoscopic lobectomy, using the DBB technique to isolate the operative lobe from the non-operative lobe(s) of the operative lung and providing CPAP to the non-operative lobe(s) through a BB can reduce the incidence of postoperative pneumonia in the operative and non-operative lungs.

Left-Sided Double-Lumen Tube vs EZ-Blocker for One-Lung Ventilation in Thoracic Surgery: A Systematic Review and Meta-Analysis

Background. The EZ-Blocker is the newest generation of bronchial blocker and offers a potential alternative to left-sided double lumen tubes for lung isolation and one-lung ventilation during thoracic surgery. Methods. Databases were searched for randomized controlled trials comparing left-sided double lumen tube to the EZ-Blocker for one-lung ventilation during thoracic surgery. The time for placement, incidence of intraoperative displacement, and surgeons' rating of lung collapse quality were designated as coprimary outcomes. The safety profiles of the two devices, including the incidence of airway trauma and post-extubation discomfort were also examined. Results. Six randomized controlled trials (495 patients) were analyzed. Compared to the EZ-Blocker, the left-sided double lumen tube was faster to place by a weighted mean difference of [95% CI] of -61.24 seconds [-102.48, -20.00] (P = .004) and was much less likely to become displaced during lung isolation with an odds ratio [95% CI] of .56 [.34, .91] (P = .02). The left-sided double lumen tube and the EZ-Blocker provided similar surgeon-rated quality of lung isolation. Although the left-sided double lumen tube caused a greater degree of post-extubation sore throat, there was a similar incidence of carinal trauma and post-extubation hoarseness compared to the EZ-Blocker. Conclusion. Our analysis suggests that the left-sided double lumen tube can be placed more quickly and is less prone to intraoperative displacement compared to the EZ-Blocker; the quality of lung collapse is similar. Thus, evidence appears to support the continued utilization of the left-sided double lumen tube for routine thoracic surgery requiring one-lung ventilation.

Is fibre-optic bronchoscopy necessary to confirm the position of rigid-angled endobronchial blockers before thoracic surgery? A randomized controlled trial

OBJECTIVES

To determine the success rate of blind insertion and the usefulness of fibre-optic bronchoscopy for directing rigid-angled endobronchial blockers (EBs) to the correct side and achieving satisfactory surgical fields.

METHODS

A randomized trial was designed to determine the extent to which the Coopdech Endobronchial Blocker Tube (Daiken Medical Co., Ltd) could successfully be placed through either auscultation (n = 57) or fibre-optic bronchoscopy (n = 55) in patients scheduled for thoracic surgery. The placement time was recorded and quality of the thoracoscopic operation field was determined by the thoracic surgeon. Anaesthesiologists with varying thoracic experience levels were enrolled.

RESULTS

The success rates of insertion through auscultation were 100% (32 of 32) for the right side and 88% (22 of 25) for the left side. Placement through auscultation was faster than that through bronchoscopy (mean 89.6 vs 141.1 s, P = 0.008) in the right-sided procedure but non-significant in the left-sided procedure (mean 138.5 vs 130 s, P = 0.795). Surgical grading of the operation field was not significantly different between both techniques (P = 0.502). Experienced anaesthesiologists took less time to position EBs (mean 91.0 vs 138.0 s, P = 0.015). Surgical grading was comparable between specialists and residents (P = 0.058).

CONCLUSIONS

Once an EB was correctly inserted and confirmed through auscultation, the corresponding surgical satisfaction was comparable to that through bronchoscopy. In the majority of cases, bronchoscopy is unnecessary for correct and efficient EB positioning. However, bronchoscopy is still mandatory in left-sided EB insertion and in patients with deviated tracheobronchial anatomy.

Clinical registration number

NCT02133235, registered at ClinicalTrials.gov [https://clinicaltrials.gov/ct2/show/NCT02133235 (8 July 2017, date last accessed)].

Congenital Lung Malformations: Shifting from Open to Thoracoscopic Surgery

BACKGROUND

Over the years the need for surgical treatment, timing of intervention, and the type of surgical approach have been discussed, but the treatment of congenital lung malformations remains controversial. The aim of this study was to compare the thoracotomy approach with the thoracoscopic technique by evaluating different surgical outcomes (duration of surgery, postoperative hospital stay, and complications).

METHODS

All patients operated from January 2011 to March 2015 for suspected congenital cystic lung were included in the study. Patients treated for congenital lobar emphysema and tracheobronchial neoplasms were excluded from the study.

RESULTS

In the analyzed period, 31 asymptomatic patients were treated: 18 lung resections were performed with thoracotomy (Group A) and 13 with the thoracoscopic approach (Group B). No significant differences were observed between the age and weight at surgery, length of the procedures, complications, and the need for postoperative intensive care between the two groups. The postoperative hospital stay in Group A was twice that for Group 2 (p = 0.0009).

CONCLUSION

Comparing thoracoscopic surgery with the traditional open approach, we confirmed the superiority of minimally invasive treatment in terms of postoperative hospital stay. Common technical recommendations can help pediatric centers to develop the thoracoscopic approach for the treatment of congenital pulmonary malformations.

Combined use of a double-lumen tube and Fogarty catheter to prevent the endobronchial spread of infection: a case report

Huntington's disease is a neurodegenerative disorder with an autosomal dominant inheritance pattern. Patients with Huntington's disease show an increased risk of aspiration pneumonia when the pharyngeal muscle is invaded. We report a case of advanced-stage Huntington's disease in which the patient received right middle lobectomy for a lung abscess caused by repeated aspiration. The best lung isolation technique has not yet been established in these patients. We successfully performed selective lobar isolation of the right lower and middle lobes using a double lumen tube and a Fogarty embolectomy catheter.

Bronchial blockers under pressure: in vitro model and ex vivo model

BACKGROUND

Pressures (Pe) exerted by bronchial blockers on the inner wall of the bronchi may cause mucosal ischaemia. Our aims were as follows: (i) to compare the intracuff pressure (Pi) and Pe exerted by commercially available bronchial blockers in an in vitro and an ex vivo model; (ii) to investigate the influence of both the inflated intracuff volume and cuff diameter on Pe; and (iii) to estimate the minimal sealing volume (VSmin) and the corresponding Pe for each bronchial blocker studied.

METHODS

The Pe exerted by seven commercial bronchial blockers was measured at different inflation volumes using a custom-designed system using in vitro and ex vivo animal models with two internal diameters (12 and 15 mm).

RESULTS

In the same conditions, Pi was significantly lower than Pe (P<0.05), and Pe was higher in the in vitro model than in the ex vivo model. The Pe increased with the inflated volume, with use of the small-diameter model (P<0.05). Ex vivo models needed a higher minimal sealing volume than the in vitro models, and this volume increased with the diameter (e.g. the VSmin at a positive pressure of 25 cm H2O required a Pe ranging from 12 to 78 mm Hg on the 15 mm ex vivo model and from 66 to 110 mm Hg on the 12 mm ex vivo model).

CONCLUSIONS

The Pi cannot be used to approximate Pe. The diameter of the model, the inflated volume, and the bronchial blocker design all influence Pe. A pressure higher than the critical ischaemic threshold (i.e. 25 mm Hg) was needed to prevent air leak around the cuff in the in vitro and ex vivo models.

Design and characterization of a measurement system for monitoring pressure exerted by bronchial blockers: In vitro trials

Bronchial blockers (BBs) allow occluding the bronchial duct and collapsing the "dependent" lung in a number of thoracic surgery. The occlusion is obtained through a cuff that, inflated with a proper air volume, exerts a pressure, Pe, on the inner wall of the mainstem bronchus. In this work a measurement chain, based on two piezorestistive force sensors, was developed and calibrated to measure Pe exerted by six BBs, as a function of inflated volume on in vitro models (two latex ducts with diameters similar to the ones of the adult mainstem bronchi: 12 mm and 15 mm). Pe showed wide changes considering different BBs, and significantly increases with the decrease of the model's diameter, at the same inflated volume. Lastly, the minimum occlusive volume (MOV) to sail the two models was estimated for each BB. These experiments were performed by applying a pressure difference across the cuff of 25 cmH2O, in order to simulate the worst condition in a clinical scenario. Results show that MOV depends on both the type of BB and the duct diameter. The knowledge of this volume allows estimating the minimum value of Pe exerted by BBs to avoid air leakage.