Combined use of a Total Control Introducer and a hyperangulated video laryngoscope to place a left-sided double lumen endotracheal tube in a patient with a history of difficult laryngoscopy

We describe the use of a Total Control Introducer (TCI) in combination with video laryngoscopy (VL) to place a left-sided double-lumen endotracheal tube (DLT) in a patient with a history of difficult laryngoscopy undergoing video-assisted thoracoscopic surgery (VATS). VL was used to obtain visualisation of the glottis and a TCI articulating introducer was used to dynamically navigate the airway and access the trachea. A 39 French DLT was subsequently passed over the TCI shaft and into the trachea under indirect visualisation. The TCI shaft was removed and the DLT was gently guided into the left main bronchus. Successful endobronchial intubation was confirmed with capnography, auscultation and fibreoptic bronchoscopy. We propose that the combined use of VL and a TCI can facilitate placement of a DLT in a patient with a known difficult airway who may otherwise be limited to a bronchial blocker placement for lung isolation during VATS.

Independent Lung Ventilation-Experimental Studies on a 3D Printed Respiratory Tract Model

Independent lung ventilation (ILV) is a life-saving procedure in unilateral pulmonary pathologies. ILV is underused in clinical practice, mostly due to the technically demanding placement of a double lumen endotracheal tube (ETT). Moreover, the determination of ventilation parameters for each lung in vivo is limited. In recent years, the development of 3D printing techniques enabled the production of highly accurate physical models of anatomical structures used for in vitro research, considering the high risk of in vivo studies. The purpose of this study was to assess the influence of double-lumen ETT on the gas transport and mixing in the anatomically accurate 3D-printed model of the bronchial tree, with lung lobes of different compliances, using various ventilation modes. The bronchial tree was obtained from Respiratory Drug Delivery (RDD Online, Richmond, VA, USA), processed and printed by a dual extruder FFF 3D printer. The test system was also composed of left side double-lumen endotracheal tube, Siemens Test Lung 190 and anesthetic breathing bag (as lobes). Pressure and flow measurements were taken at the outlets of the secondary bronchus. The measured resistance increased six times in the presence of double-lumen ETT. Differences between the flow distribution to the less and more compliant lobe were more significant for the airways with double-lumen ETT. The ability to predict the actual flow distribution in model airways is necessary to conduct effective ILV in clinical conditions.

Monitoring of carbon dioxide in ventilated neonates: a prospective observational study

ObjectiveTo assess the reliability, accuracy and precision of distal end-tidal capnography (detCO2) in neonates compared with transcutaneous (tcCO2) carbon dioxide measurements.DesignObservational, prospective clinical study.SettingNeonatal intensive care unit at Medical University of Vienna.ParticipantsConventionally ventilated neonates with a body weight between 1000 g and 3000 g.InterventionEnd-tidal partial pressure of CO2 was measured in distal position using the separate lumen of a double-lumen endotracheal tube connected to an external side-stream capnometer. Three consecutive detCO2 and tcCO2 values were recorded simultaneously and compared with simultaneous arterialised partial pressure of CO2 (paCO2) measurements in each patient.Main outcome measuresReliability, accuracy and precision of detCO2 and tcCO2 measurements compared with paCO2 in neonates.ResultsTwenty-five neonates were included with a median (range) weight at enrolment of 1410 (1010–2980) g, from which 81 simultaneous measurements of detCO2, tcCO2 and paCO2 were obtained. The mean (SD) of paCO2, detCO2 and tcCO2 was 45.0 (8.6) mmHg, 42.4 (8.4) mmHg and 50.4 (20.4) mmHg, respectively. The intraclass correlation between paCO2 and detCO2 and between paCO2 and tcCO2 reached 0.80 (95% CI 0.71 to 0.87, p<0.001) and 0.59 (95% CI 0.43 to 0.72, p<0.001), respectively. In the Bland-Altman analysis, bias and precision of detCO2 with respect to paCO2 amounted to −2.68 mmHg and 10.62 mmHg (95% CI 8.49 to 14.51), respectively. Bias and precision of tcCO2 with respect to paCO2 amounted to 5.39 mmHg and 17.22 mmHg (95% CI 13.21 to 23.34), respectively.ConclusionDetCO2 had better reliability, accuracy and precision with paCO2 than tcCO2 in ventilated neonates without severe lung diseas.Trial registration numberNCT03758313.

Improvement of surgical complications using single-lumen endotracheal tube intubation and artificial carbon dioxide pneumothorax in esophagectomy: a meta-analysis

Background Esophageal cancer has a poor prognosis. Surgery is the main treatment but involves a high risk of complications. Some surgical strategies have tried to eliminate complications. Our meta-analysis tried to find the benefits of single-lumen endotracheal tube intubation with carbon dioxide (CO2) inflation. Methods A systematic search of studies on esophagectomy and CO2 inflation was conducted using PubMed, Medline, and Scopus. The odds ratio of post-operative pulmonary complications and anastomosis leakage were the primary outcomes. The standardized mean difference (SMD) in post-operative hospitalization duration was the secondary outcome. Results The meta-analysis included four case-control studies with a total of 1503 patients. The analysis showed a lower odds ratio of pulmonary complications in the single-lumen endotracheal tube intubation in the CO2 inflation group (odds ratio: 0.756 [95% confidence interval, CI: 0.518 to 1.103]) compared to that in the double-lumen endotracheal tube intubation group, but anastomosis leakage did not improve (odds ratio: 1.056 [95% CI: 0.769 to 1.45])). The SMD in hospitalization duration did not show significant improvement. (SMD: -0.141[95% CI: − 0.248 to − 0.034]). Conclusions Single-lumen endotracheal tube intubation with CO2 inflation improved pulmonary complications and shortened the hospitalization duration. However, no benefit in anastomosis leakage was observed.

SLL-PEEP Ventilation to Improve Exposure in Minimally Invasive Right Anterolateral Minithoracotomy Aortic Valve Replacement

Objective An accepted landmark to assess feasibility of surgical aortic valve replacement (SAVR) via right anterolateral minithoracotomy (RALT) is the aortic-midpoint to right-sternal-edge distance. We aimed to evaluate single left lung positive-end-expiratory-pressure (SLL-PEEP) ventilation inducing an intraoperative rightward shift of the ascending aorta to improve exposure. Methods Nineteen patients with aortic stenosis undergoing SAVR via RALT were prospectively analyzed. SLL-PEEP ventilation (20,395 cmH2O) via a double-lumen endotracheal tube was applied immediately before transthoracic aortic cross-clamping, thereby inducing rightward shift of the ascending aorta to enhance exposure. We analyzed preoperative computed tomography (CT) reconstructions and intraoperative video recordings. Primary endpoint was extent of rightward shift induced by SLL-PEEP ventilation; secondary endpoints were procedure times and safety events. Results Mean age was 61 ± 14.8 years and 6 of 19 (31.6%) were female. Mean EuroSCORE II was 0.81% ± 0.04%, STS-PROM was 1.13% ± 0.74%, and mean aortic rightward shift induced by SLL-PEEP ventilation was 10.32 ± 4.14 mm (4 to 17 mm; P = 0.003). Median shift in the group considered suitable for the RALT approach by preoperative CT-scan evaluation was 14.2 mm (IQR 11) and in the less suitable group 11.5 mm (IQR 5). Mean procedure time was 167 ± 28.9 min, CPB time was 105.7 ± 18.4 min, and cross-clamp time was 64.5 ± 13 min. Fifteen patients (79%) received SAVR via RALT with implantation of a bioprosthesis, whereas a rapid-deployment-prosthesis was used in 4 patients (21%). Ten of 19 (53%) patients who were classified as less suitable preoperatively received SAVR via RALT after SLL-PEEP ventilation. No strokes were observed. Conclusions The SLL-PEEP ventilation maneuver during SAVR via RALT significantly enhances aortic exposure. There were no safety events associated with this maneuver and we were able to demonstrate significant rightward aortic shift in every single patient.

Changes in the Bronchial Cuff Pressure of Left-Sided Double-Lumen Endotracheal Tube by Lateral Positioning: A Prospective Observational Study

Proper bronchial cuff pressure (BCP) is important when using a double-lumen endotracheal tube (DLT), especially in thoracic surgery. As positional change during endotracheal tube placement could alter cuff pressure, we aim to evaluate the change in BCP of DLT from the supine to the lateral decubitus position during thoracic surgery. A total of 69 patients aged 18–70 years who underwent elective lung surgery were recruited. BCP was measured at a series of time points in the supine and lateral decubitus positions after confirming the DLT placement. The primary outcome was change in the initial established BCP (BCPi), which is the maximum pressure at which the BCP did not exceed 40 cmH2O without air leak in the supine position, after lateral decubitus positioning. As the primary outcome, the BCPi increased from 25.4 ± 9.0 cmH2O in the supine position to 29.1 ± 12.2 cmH2O in the lateral decubitus position (p < 0.001). Out of the 69 participants, 43 and 26 patients underwent surgery in the left-lateral decubitus position (LLD group) and the right-lateral decubitus position (RLD group) respectively. In the LLD group, the BCPi increased significantly (p < 0.001) after lateral positioning and the beginning of surgery and the difference value, ∆BCPi, from supine to lateral position was significantly higher in the LLD group than in the RLD group (p = 0.034). Positional change from supine to lateral decubitus could increase the BCPi of DLT and the increase was significantly greater in LLD that in RLD.