A Randomised Control Study Comparing Ultrasonography with Standard Clinical Methods in Assessing Endotracheal Tube Tip Positioning.

Introduction: Airway ultrasound has been increasingly used in correct positioning of endotracheal tube. We hypothesize that a safe distance between endotracheal tube tip and carina can be achieved with the aid of ultrasound. Aim of the study: Our primary objective was to determine whether ultrasound guided visualisation of proximal end of endotracheal tube cuff is better when compared to conventional method in optimal positioning of tube tip. The secondary objective was to find the optimal endotracheal tube position at the level of incisors in adult Indian population. Materials and Methods: There were 25 patients each in the conventional group and the ultrasound group. Conventional method includes auscultation and end tidal capnography. In the ultrasound group the upper end of the endotracheal tube cuff was positioned with an intent to provide 4 cm distance from the tube tip to the carina. X ray was used in both groups for confirmation of tip position and comparison between the two groups. Further repositioning of the tube was done if indicated and the mean length of the tube at incisors was then measured. Results: After x ray confirmation, endotracheal tube repositioning was required in 24% of patients in the USG group and 40 % of patients in the conventional group. However, this result was not found to be statistically significant (p = 0.364). The endotracheal tube length at the level of teeth was 19.4 ± 1.35 cm among females and 20.95 ± 1.37 cm among males. Conclusions: Ultrasonography is a reliable method to determine ETT position in the trachea. There was no statistically significant difference when compared to the conventional method. The average length of ETT at the level of incisors was 19.5 cm for females and 21 cm for males.

Evaluation of the position of the central venous catheter tip of implantable venous access devices in the occurrence of postoperative thrombotic and non-thrombotic complications.

BACKGROUND: The position of the catheter tip of totally implantable venous access devices (TIVAD) is a risk factor for postoperative complications. The study aim was to assess the early and late complications (EC and LC) associated with the position of the catheter tip in cancer patients. METHODS: We reviewed cancer patients who had a TIVAD placed in 2020. EC (≤ 90 days), LC (> 90 days) and risk factors for TIVAD-associated complications were assessed. The vertical mismatch of the catheter tip was compared to an "ideal position" (> 10 mm below the carina and ≥ 20 mm below the right main bronchus (RMB)) using chest x-ray, post-implantation. RESULTS: 301 patients were included. Median follow-up after TIVAD implantation was 9.4 months. All TIVAD catheters were inserted via the internal jugular vein (IJV). The mean distance between the catheter tip and the carina and the RMB was 21.3 mm and 6.63 mm respectively. In total, 11.3% patients developed EC and 5.6% had LC. An association was found between the position of the catheter tip from the carina (≤ 10 mm vs. > 10 mm) and the occurrence of EC (18.3% vs. 8.6%, p = 0.01) and for the catheter insertion side (left IJV vs. right IJV) (19.1% vs. 9.0% p = 0.02). Multivariate analysis showed that left IJV catheter insertion (OR 2.76), and a catheter tip located ≤ 10 mm below the carina (OR 2.71) are significant independent risk factors of EC. CONCLUSIONS: TIVAD catheter tip located at ≤ 10 mm below the carina, and a left-side inserted catheter, are higher risk of EC.

Case report: Complex left-carina resection: three-year single-center experience.

Carinal and tracheobronchial angle tumors have long been a contraindication for surgical removal; the technique of tracheal sleeve pneumonectomy makes it possible to approach this malignancy but still represents a surgical challenge. Left sleeve pneumonectomy is less common compared with right sleeve pneumonectomy and represents a minority component in the literature's case series due to the complexity of the anatomy. In addition, there is no standard for treatment strategy, and it must be assessed on a case-by-case basis. From 2020 to 2023, we performed three left tracheal sleeve pneumonectomies and one neocarina reconstruction surgery for benign lesions without lung resections. All cases were performed without cardiovascular support such as cardiopulmonary bypass and via median sternotomy. With a median length of stay of 21.5 days (between 14 days and 40 days), all patients were transferred to a physiotherapeutic rehabilitation facility for functional reactivation, where they received physiotherapeutic respiratory therapy given the slow functional recovery. The recorded 30-day mortality was 0. There is no standardized approach for left-sided sleeve pneumonectomy, and it is still a surgical challenge due to intraoperative and postoperative difficulties.

Role of VV ECMO tracheal surgery and carinal resection: Two case reports.

The aim of this study is to describe the anaesthesia management of two patients undergoing carinal resection under veno-venous extracorporeal membrane oxygenation (VV ECMO). In both cases, anaesthesia was induced and then maintained with inhalational agents during pneumonectomy and mediastinoscopy (respectively). Then the jugular and femoral veins were cannulated and VV ECMO was started after heparinization. One of the patients presented bleeding during surgery, which was treated with low-dose vasopressors (norepinephrine) and transfusion of platelets, fresh frozen plasma, and concentrated red blood cells. During VV ECMO, anaesthesia was maintained with target-controlled infusion of propofol. VV ECMO can be expected to improve surgical conditions in tracheal surgery; however, it is still a novel technique in this context. In selected patients, it would guarantee ventilatory support during carinal resection, but it is essential to carefully plan anaesthesia maintenance and prepare for VV ECMO-related complications. This technique should only be used in tertiary centres with experience in VV ECMO management.

One-year outcomes of wide antral cryoballoon ablation guided by high-density mapping vs. conventional cryoballoon ablation for atrial fibrillation: a propensity score-matched study.

Background: Pulmonary vein isolation with wide antral ablation leads to better clinical outcomes for the treatment of atrial fibrillation, but the isolation lesion is invisible in conventional cryoballoon ablation. In this study, we aim to investigate the efficacy of the wide pulmonary vein isolation technique that includes the intervenous carina region, guided by high-density mapping, compared with pulmonary vein isolation alone without the mapping system. Methods: We conducted a propensity score-matched comparison of 74 patients who underwent a wide cryoballoon ablation guided by high-density mapping (mapping group) and 74 controls who underwent conventional cryoballoon ablation in the same period (no-mapping group). The primary outcome was a clinical recurrence of documented atrial arrhythmias for >30 s during the 1-year follow-up. Results: Of 74 patients in the mapping group, residual local potential in the pulmonary vein antrum was found in 30 (40.5%) patients, and additional cryothermal applications were performed to achieve a wide pulmonary vein isolation. Compared with the no-mapping group, the use of the mapping system in the mapping group was associated with a longer fluoroscopic time (26.97 ± 8.07 min vs. 23.76 ± 8.36 min, P = 0.023) and greater fluoroscopic exposure [339 (IQR181-586) mGy vs. 224 (IQR133-409) mGy, P = 0.012]. However, no significant differences between the two groups were found in terms of procedural duration and left atrial dwell time (104.10 ± 18.76 min vs. 102.45 ± 21.01 min, P = 0.619; 83.52 ± 17.01 min vs. 79.59 ± 17.96 min, P = 0.177). The rate of 12-month freedom from clinical atrial arrhythmia recurrence was 85.1% in the mapping group and 70.3% in the no-mapping group (log-rank P = 0.029). Conclusion: Voltage and pulmonary vein potential mapping after cryoballoon pulmonary vein isolation can identify residual potential in the pulmonary vein antrum, and additional cryoablation guided by mapping leads to improved freedom from atrial arrhythmias compared with conventional pulmonary vein isolation without the mapping system. Clinical Trial Registration Number: ChiCTR2200064383.

Lower contact force predicts right pulmonary vein carina breakthrough after ablation index-guided pulmonary vein isolation using high-power short-duration.

INTRODUCTION: Carina breakthrough (CB) at the right pulmonary vein (RPV) can occur after circumferential pulmonary vein isolation (PVI) due to epicardial bridging or transient tissue edema. High-power short-duration (HPSD) ablation may increase the incidence of RPV CB. Currently, the surrogate of ablation parameters to predict RPV CB is not well established. This study investigated predictors of RPV CB in patients undergoing ablation index (AI)-guided PVI with HPSD. METHODS: The study included 62 patients with symptomatic atrial fibrillation (AF) who underwent AI-guided PVI using HPSD. Patients were categorized into two groups based on the presence or absence of RPV CB. Lesions adjacent to the RPV carina were assessed, and CB was confirmed through residual voltage, low voltage along the ablation lesions, and activation wavefront propagation. RESULTS: Out of the 62 patients, 21 (33.87%) experienced RPV CB (Group 1), while 41 (66.13%) achieved first-pass RPV isolation (Group 2). Despite similar AI and HPSD, patients with RPV CB had lower contact force (CF) at lesions adjacent to the RPV carina. Receiver operating characteristic (ROC) curve analysis identified CF < 10.5 g as a predictor of RPV CB, with 75.7% sensitivity and 56.2% specificity (area under the curve: 0.714). CONCLUSION: In patients undergoing AI-guided PVI with HPSD, lower CF adjacent to the carina was associated with a higher risk of RPV CB. These findings suggest that maintaining higher CF during ablation in this region may reduce the occurrence of RPV CB.

A Cadaveric Case Report of a Double Right Coronary Artery and Its Clinical Implications.

A double right coronary artery is one of the rarest variations of the coronary arterial system. This case report presents a unique variation: a right coronary and an accessory coronary artery arise from a single ostium within the right aortic sinus. The two vessels appeared externally to have a common trunk but were partitioned internally by a carina-like septum. This report underscores the importance of understanding the embryological development of coronary arteries and recognizing potential variations. It discusses the specific variation observed in this case and its clinical implications. The aim is to contribute to the limited literature on this condition and highlight the importance of recognizing and managing such anomalies in clinical procedures.

The impact of endotracheal intubation on oxygen delivery, trachea pressure and wall deformation.

This paper concerns improving endotracheal tube (ETT) insertion through advanced computational science modelling. The study aims to better understand endotracheal intubation (ETI) and reduce medical errors in intensive and critical care units since ETT insertion is unique for each patient, depending on age, gender, size, physiology, and underlying health conditions. We have employed computational fluid dynamics and biomechanics modelling to investigate the effect of ETT for three ventilation modes on (a) local oxygen delivery to the lungs, (b) air pressure and wall shear stress at the tracheal walls, and (c) oscillatory elastic deformation of the tracheal tissues and muscle. For the first time, we reveal how the ventilation mode and ETT insertion in the trachea may induce major complications, especially in long periods of ETT. We show that rotating the ETT or displacing it by 2 mm only can induce a significant rise in the tracheal pressure up to 177 cmH2O. This study, for the first time, shows the vital role of computers in biology and medicine to provide enhanced decision-making-support to clinicians and medical doctors dealing with ETI.

Ideal endotracheal intubation depth at the vocal-cord level to avoid single-lung intubation using the percentage ratio of the tracheal length to body height.

INTRODUCTION: Our previous study revealed racial differences in the tracheal length of cardiac paediatric patients between Germany and Japan. The current study was conducted in two stages, aiming to determine whether the tracheal length differs between cardiac and non-cardiac paediatric patients and whether the results could also be generalised to adults. MATERIAL AND METHODS: The first stage was a retrospective observational evaluation of 335 cardiac and 275 non-cardiac paediatric patients in Japan. The tracheal length, the distance between the vocal cords and carina tracheae, was measured on preoperative chest radiographs taken in the supine position. The second stage was a validation process including 308 Japanese patients. Endotracheal intubation was performed based on the results of the first-stage investigation. RESULTS: It was revealed that the tracheal length ranged from 7 to 11% of the body height in both the cardiac and non-cardiac Japanese paediatric patients. None of 308 Japanese paediatric and adult patients underwent single-lung intubation after the endotracheal tube was inserted at a depth of 7% of the body height at the vocal-cord level, corresponding to the minimum tracheal length for Japanese patients. The distance between the endotracheal tube tip and carina tracheae on postoperative chest radiographs was generally less than 4% of the body height across all paediatric and adult Japanese patients. CONCLUSIONS: The current study demonstrated that endotracheal intubation avoiding single-lung intubation can be achieved by inserting endotracheal tubes to the minimum tracheal length for a specific ethnic group at the vocal-cord level in paediatric patients, including neonates and premature infants, as well as adults.

Short- and medium-term outcomes of video-assisted thoracoscopic surgery versus thoracotomy for carinal lung resection combined with carina reconstruction in locally advanced non-small cell lung cancer patients.

BACKGROUND: The application of video-assisted thoracoscopic surgery (VATS) for complex carina surgeries in treating non-small cell lung cancer (NSCLC) patients with involved carina is controversial. This study compared short- and medium-term outcomes of VATS versus thoracotomy for carinal lung resection with carina reconstruction in treating locally advanced NSCLC, aiming to assess the potential benefit of VATS over thoracotomy for these patients. METHODS: A total of 37 consecutive NSCLC cases receiving VATS (n = 14) or thoracotomy (n = 23) for carinal lung resection with carina reconstruction from 2016 to 2021 were retrospectively identified. Baseline clinicopathological characteristics, perioperative outcomes, and survival profiles were investigated. RESULTS: Patients in the VATS and thoracotomy groups had comparable baseline clinicopathological characteristics (all p > 0.050). VATS decreased postoperative drainage volume compared with thoracotomy (1280 [1170-1510] vs. 1795 [1510-1905] mL, p = 0.012). Regarding surgical-related pains, VATS reduced numeric rating scale scores on the postoperative day 1 (4 [3, 4] vs. 5 [4, 5], p = 0.021) and day 2 (3 [3, 4] vs. 5 [3-5], p = 0.023) than thoracotomy. No difference was found between the VATS and thoracotomy groups in other perioperative outcomes, postoperative complications, and assessment of lymph nodes (LNs) and LN stations (all p > 0.050). Moreover, patients in the two groups had comparable 3-year disease-free survival (DFS), overall survival (OS), and recurrence and mortality patterns. Further subgroup and Cox hazards regression analyses also observed no difference in DFS or OS between the two groups. CONCLUSIONS: VATS reduced postoperative drainage volume and ameliorated surgical-related pain, and achieved comparable medium-term survival compared to thoracotomy for carinal lung resection with carina reconstruction in treating locally advanced NSCLC.

Neo-carina after carina resection and right upper lobectomy in a patient with adenoid cystic carcinoma: Alternative technique.

Surgical treatment of carinal tumors that extend into the lobar bronchus is a procedure that challenges thoracic surgeons. There is no consensus on the suitable technique for a safe anastomosis in lobar lung resection with carina. The preferred Barclay technique has a high rate of anastomosis-related complications. Although a lobe-sparing end-to-end anastomosis technique has been previously described, the double-barrel method can be applied as an alternative technique. We present a case where we performed double-barrel anastomosis and neo-carina formation after tracheal sleeve right upper lobectomy.

The spine and carina as a surrogate for target registration in cone-beam CT imaging verification in locally advanced lung cancer radiotherapy.

BACKGROUND: The aim of the study was to evaluate the accuracy of volumetric lung image guidance using the spine or carina as a surrogate to target for image registration, as the best approach is not established. PATIENTS AND METHODS: Cone beam computed tomography images from the 1st, 10th, 15th, and 20th fraction in 40 lung cancer patients treated with radical radiotherapy were retrospectively registered to planning CT, using three approaches. The spine and carina alignment set-up deviations from a reference (tumour/lymph nodes) registration in the lateral (LAT), longitudinal (LONG) and vertical (VRT) directions were analysed and compared. Tumour location and nodal stage influence on registration accuracy were explored. RESULTS: The spine and carina mean set-up deviation from reference were largest in the LONG, with the best match in the VRT and LAT, respectively. Both strategies were more accurate in central tumours, with the carina being more precise in 50% LAT and 66% LONG mean deviations. For all measurements in all patients a carina vs. spine registration comparison showed improved carina accuracy in LAT and LONG. In comparative subgroup analysis the carina was superior compared to spine in LAT and LONG in centrally located tumours, N2 and N3. Both strategies were comparable for peripheral tumours and N0. CONCLUSIONS: Carina registration shows greater accuracy compared to spine in the LAT and LONG directions and is superior in central tumours, N2 and N3. The spine and carina surrogates are equally accurate for peripheral tumours and N0. We propose the carina as a surrogate to target for CBCT image registration in locally advanced lung cancer.

Differential gap location after radiofrequency versus cryoballoon pulmonary vein isolation: Insights from a randomized trial with protocol-mandated repeat procedure.

INTRODUCTION: Reconnections to pulmonary vein (PV) triggers of atrial fibrillation (AF) are the primary cause of AF recurrence after PV isolation (PVI) with radiofrequency (RF) or cryoballoon catheter ablation (CRYO), but method-specific contributions to PV reconduction pattern and conductive gap location are incompletely understood. METHODS: The objective of this radiofrequency versus cryoballoon catheter ablation for paroxysmal atrial fibrillation substudy was to determine procedure-specific patterns of PV reconduction in a randomized population with protocol-mandated repeat procedures, irrespective of AF recurrence. Each PV was assessed in turn and PV reconnection sites were identified by high-density electroanatomical mapping and locating the earliest activation site. Gap locations were verified by PV re-isolation. RESULTS: In 98 patients, 81% versus 76% previously isolated PVs remained isolated after CRYO versus RF (risk ratio [RR]: 1.06; 95% confidence interval [CI]: 0.96-1.18; p = .28). There were no significant differences for any PV: left superior PV: 90% versus 80%; left inferior PV: 80% versus 78%; right superior PV: 81% versus 80%, and right inferior PV: 76% versus 73%. For each reconnected PV, 34% of ipsilateral PVs were also reconnected after CRYO compared with 64% after RF (RR: 0.54; 95% CI: 0.32-0.90; p = .01). After RF, gaps were clustered by the carina and adjacent segments, whereas they were more heterogeneously distributed after CRYO. CONCLUSION: Although RF and CRYO produce similar proportions of durably isolated PVs, gap locations appear to develop in procedure-specific patterns. After RF, ipsilateral PV reconduction is more frequent and gap sites cluster by the carina, suggesting that this region should be selectively ablated for more durable PVI.

Intraobserver repeatability for a standardized protocol to quantify keel bone damage in laying hens using discrete and continuous radiographic measures.

Sternal carina damage (keel bone damage, KBD) is an important welfare concern for laying hen producers and backyard flock owners. Quantitative radiographic measures of KBD severity are helpful for researchers who study causes for this problem and the effects of novel interventions. The objectives of the current retrospective secondary analysis study were to develop and test intraobserver repeatability for a standardized protocol to quantify three categories of radiographic KBD using open-source image analysis software and discrete and continuous variables. The standardized protocol was developed and evaluated using triplicate measurements of 470 keel bone radiographs that had been previously acquired for a prospective study. Intraobserver repeatability was assessed using intra-class correlation coefficient (ICC) and control chart methods. Based on control chart analyses, measures within the acceptable range of intra-observer variation using the standardized protocol were the number of complete cranial fractures (97.02%), incomplete cranial fractures (96.38%), complete caudal fractures (95.32%), incomplete caudal fractures (98.09%), cranial calluses (99.79%), and caudal calluses (98.09%); proportion of deviation (POD) measurements (97.87%); and angle of displacement (AOD) measurements (93.60%). Findings can be used as background to support future research studies on KBD in laying hens.

Shape differences of the Carina sterni in birds of various locomotion types.

The anatomy of the sternum in birds varies according to their habitats and type of locomotion. In particular, the carina sterni manifest different shape variations. In this study, the shape of the carina sterni was investigated by means of geometric morphometrics. Birds of different types of locomotion were used in the study: flying, swimming, and terrestrial. Ducks and chickens show a wider variety of shapes. Pigeons are the species with the least differences. The margo cranialis carinae in a turkey is the flattest compared to other species. In chickens, the apex carinae is more caudally than the base of the carina sterni. The margo cranialis of the carina sterni in ducks is concave. The differences in centroid size and shape differences between species collectively are statistically significant (p < 0.0001). The most distinct shape contrast is between the duck and turkey (p: 0.0003). Form differences between the ducks and geese as well as between the chicken and turkey are statistically insignificant. There is less variation in the shape of the carina sterni among avian species representing the same type of locomotion. Although there are many comparative morphological and morphometric studies of birds, shape analysis studies revealing the interspecific differences and similarities of the sternum are very limited. Morphology of the carina sterni can be useful in taxonomic investigations.

Tracheal Bronchus Detected During General Anesthesia: A Case Report.

A tracheal bronchus is a congenital abnormality of the tracheobronchial tree in which a displaced or accessory bronchus arises from the trachea superior to its bifurcation. We herein report a case in which a tracheal bronchus was incidentally found after induction of general anesthesia, and we discuss the potential airway management problems that may have ensued. An 80-year-old man was scheduled for buccal mucosa resection and abdominal skin grafting for treatment of squamous cell carcinoma of the left buccal mucosa. Because of trismus and anticipated airway difficulty, an awake intubation was performed under sedation. A 3-branched structure was incidentally observed at the first branching site that was supposed to be the carina. The tip of the endotracheal tube was repositioned 3 cm above the tracheal trifurcation, and the rest of the procedure proceeded uneventfully. A flexible fiberoptic scope is not used in many anesthesia cases, making the identification of such tracheal or bronchial abnormalities more difficult. Therefore, it is important to carefully check the bronchial morphology on any available chest radiographs before surgery, listen to lung sounds after intubation, and assess thoracic lung compliance without neglecting routine safety checks.

Three cases of rigid bronchoscopic removal of carinal masses: Case report.

Tracheal tumors are rare diseases. They can cause narrowing of a central airway, a severe respiratory distress, and death. The objective of this case series is to highlight the role of rigid bronchoscopy in diagnosing and treating carina masses which are difficult to remove surgically. Tumor excision was performed by the rigid bronchoscopic intervention. Additional treatment was administered according to the diagnosis of each individual patient. After the procedure, patients' symptoms were improved and stenotic central airways were reopened. Rigid bronchoscopy can be a good therapeutic option to reestablish airway patency and a bridge treatment for further definitive treatment.

Inability to perform 'en bloc' pulmonary vein isolation requiring ablation of the intervenous carina increases recurrence of atrial fibrillation: A meta-analysis.

INTRODUCTION: Failure to isolate ipsilateral pulmonary veins (PV) "en bloc" by wide-area circumferential ablation (WACA) may necessitate ablation at the intervenous carina. It is unknown how this scenario impacts rates of atrial fibrillation (AF) recurrence. METHODS: A standard random-effect meta-analysis of randomized or observational studies were performed, where the outcome of first-time AF ablation was reported in patients with "en bloc" isolation of PVs by WACA as compared with those in whom ablation at the intervenous carina was needed after WACA to achieve complete isolation. RESULTS: A total of five single-center, observational studies (N = 1185) and one, multi-center randomized trial (N = 234) were enrolled. PV isolation could be achieved by WACA "en bloc" in 902/1419 (63.6%) cases. The rest required additional ablation at one or both of the left and right intervenous carinas to achieve isolation. The follow-up time after ablation ranged from 1 to 2 years in the included trials. The incidence of AF recurrence proved to be significantly lower in patients with successful "en bloc" isolation compared to those requiring carina ablation(s) to achieve complete bilateral PV isolation (MH-OR 1.89, 95% CI 1.42-2.53, p < .01) CONCLUSION: This present meta-analysis demonstrates a lower arrhythmia recurrence rate in patients with bilateral "en bloc" isolation, as compared to those who needed additional carina ablation for complete PVI. Therefore, it is imperative that every effort be made to isolate ipsilateral PVs "en bloc" during PVI.

Trachway® flexible stylet facilitates the correct placement of double-lumen endobronchial tube: a prospective, randomized study.

BACKGROUND: The mainstream facilitation of one-lung ventilation is using double-lumen endobronchial tubes. However, it is more difficult to be positioned properly and more likely to cause airway injuries. How to place double-lumen endobronchial tubes rapidly and correctly is important for thoracic anesthesiologists. METHODS: One hundred eight patients with an American Society of Anesthesiologists physical status of I to III were 20 years of age or over, and required one-lung ventilation for thoracic surgery. They were randomly assigned to the conventional technique group (n = 36), the flexible fiberoptic bronchoscopy group (n = 36), or the Trachway® flexible stylet group (n = 36). The primary endpoint was the time needed for intubation. T1, the time from the tip of the blade passing between the patient's lips to identification of the vocal cords; and T2, the time from identification of the vocal cords to the bronchial lumen was in the correct position. RESULTS: T1 had no significant difference between groups, but T2 was significantly shorter in the Trachway® flexible stylet group (p < 0.0001) and longer in the conventional technique group (p < 0.0001). CONCLUSIONS: Using Trachway® flexible stylet for correct placement of double-lumen endobronchial tubes not only significantly shortened the intubation time, but also reduced incidence of carinal injuries. It is an alternative, and a choice with good safety. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02364622, 18/02/2015, Retrospectively registered.