RAPID IDENTIFICATION OF ETIOLOGICAL AGENTS OF RESPIRATORY TRACT INFECTIONS DURING THE COVID-19 PANDEMIC USING THE MULTIPLEX-PCR METHOD.

Objective. Most respiratory infections have similar symptoms, so it is clinically difficult to determine their etiology. This study aimed to show the importance of molecular diagnostics in identifying the etiological agent of respiratory infections, especially during the coronavirus disease 2019 (COVID-19) pandemic. Methods. A total of 849 samples from patients hospitalized at the University Clinical Center Kragujevac (from January 1 to August 1, 2022) were examined using automated multiplex-polymerase chain reaction (PCR) tests. The BioFire-FilmArray-Respiratory Panel 2.1 test was used for 742 nasopharyngeal swabs [identification of 19 viruses (including SARS-CoV-2) and four bacteria], while the BioFire-FilmArray-Pneumonia Panel was used [identification of 18 bacteria and nine viruses] (BioMerieux, Marcy l'Etoile, France) for 107 tracheal aspirates. The tests were performed according to the manufacturer's instructions, and the results were available within an hour. Results. In 582 (78.4%) samples, the BioFire-FilmArray-Respiratory Panel 2.1 plus test identified at least one pathogen. The rhinovirus (20.6%), SARS-CoV-2 (17.7%), influenza A (17.5%), respiratory syncytial virus (12.4%), and parainfluenza 3 (10.1%) were the most common. Other viruses were found less frequently, and Bordetella parapertussis was detected in one sample. In 85 (79.4%) samples, the BioFire-FilmArray-Pneumonia Panel test identified at least one bacterium or virus. The most prevalent bacteria were Staphylococcus aureus (42.4%), Haemophilus influenzae (41.2%), Streptococcus pneumoniae (36.5%), Moraxella catarrhalis (22.3%), and Legionella pneumophila (2.4%). Among viruses, rhinovirus (36.5%), adenovirus (23.5%), influenza A (11.8%), and the genus Coronavirus (4.7%), were detected. Conclusion. Multiplex-PCR tests improved the implementation of therapeutic and epidemiological measures, preventing the spread of the COVID-19 infection and Legionnaires' disease.Copyright © 2022, Serbian Medical Society. All rights reserved.

INVESTIGATION OF THE ANTIBIOTIC RESISTANCE PROFILE OF KLEBSIELLA PNEUMONIAE ISOLATES ISOLATED FROM DIFFERENT CLINICAL SPECIMENS: ONE-YEAR DATA DURING THE COVID-19 PANDEMIC PROCESS.

Objective: In recent years, the rapid spread of resistance caused by the production of extended-spectrum beta-lactamase (ESBL) among bacteria has increased the importance of K. pneumoniae bacteria. Regular monitoring of antibiotic resistance rates of bacteria is very important for the treatment of infections and new treatment methods that can be developed. In the study, it was aimed to determine the antibiotic resistance profiles and ESBL positivity rates of K. pneumoniae isolated from patients who applied to Biruni University Hospital between March 2020 and March 2021, covering the COVID-19 Pandemic. Material(s) and Method(s): In the study, antibiogram test results and ESBL presences of K. pneumoniae bacteria isolated from samples sent from different outpatient clinics and services were evaluated retrospectively. GraphPad InStat V. 3.05 was used for statistical analysis. Result and Discussion: In the study, 423 K. pneumoniae bacteria were isolated from different clinical samples. Of the isolates, 161 (38%) were obtained from the endotracheal aspirate (ETA) sample, and 349 (82.5%) were obtained from the intensive care clinic. In addition, 358 (84.63%) of the isolates were ESBL positive and 65 (15.36%) ESBL negative. It was observed that the majority of the isolates obtained were resistant to ampicillin, and almost all of the ESBL positive isolates were resistant to ceftazidime. Both the studies and the results of the study show that the number of K. pneumoniae strains showing multiple antibiotic resistance has increased over time and this increase continues exponentially.Copyright © 2023 University of Ankara. All rights reserved.

Identification of Host Proteins Interacting with IBV S1 Based on Tracheal Organ Culture.

Infectious bronchitis virus (IBV) belongs to the gamma-coronavirus genus of Coronaviridae and causes serious infectious diseases in the poultry industry. However, only a few IBV strains can infect avian passage cell lines, seriously hindering the progress of basic research on IBV pathogenesis. Whereas IBV field strains can replicate in tracheal ring organ culture (TOC) without any previous adaptation in chicken embryos or primary cells. In this study, to investigate the potential use of TOC as an in vitro infection model for the study of IBV-host interaction, we first established a chicken embryo TOC culture system and carried out an investigation on the IBV replication kinetics in the system. We found that the selected strains of the IBV GI-1, GI-7, GI-13, GI-19, and GI-22 genotypes could successfully replicate in TOC and bring about damage to the infected trachea. Next, we identified host proteins of the chicken embryo trachea that interact with the IBV S1 protein by immunoprecipitation and protein mass spectrometry. A total of 127 candidate proteins were initially identified with major involvement in cell adhesion pathways and apoptosis- and autophagy-related pathways. The heat shock protein 70 (HSP70) was selected for further investigation in the interaction with IBV viral proteins. Our results showed that HSP70 interacted with IBV S1 in both TOC and CEK cells, whereas HSP70 overexpression inhibited viral replication. This study indicates that TOC is a good system for the elucidation of IBV-host interactions and HSP70 is a potential host antiviral factor.

Efficacy of McGRATH®MAC videolaryngoscope blade 1 for tracheal intubation in small children: a randomized controlled clinical study.

BACKGROUND: Videolaryngoscopes may not be as effective in small children as they are in older children and in adults. The size 1 blade is commercially available for the McGRATH®MAC videolaryngoscope (Covidien, Medtronic, Tokyo, Japan), but its efficacy in comparison with a Macintosh laryngoscope blade 1 is not known. AIM: The main aim of this study was to assess the efficacy of McGrath®MAC blade 1 in comparison with a conventional Macintosh laryngoscope blade 1, in children aged less than 24 months. METHODS: Thirty-eight children aged less than 24 months were randomly allocated to one of two groups, and tracheal intubation was attempted using either a direct laryngoscope with a Macintosh blade 1 or a videolaryngoscope with a McGRATH®MAC blade 1. In another 12 children aged 2-4 years, the same comparisons were made with blade 2. The primary outcome measure was time to tracheal intubation using a size 1 blade. RESULTS: Tracheal intubation took significantly longer with a McGRATH®MAC blade 1 (median (interquartile range): 38.0 (31.8-43.5) s) than with the Macintosh blade 1(27.4 (25.9-29.2) s) (p < 0.0001; median difference (95% CI for the median difference): 10.6 (6.4-14.0) s), mainly due to difficulty in advancing a tube into the trachea. No significant difference was observed for the size 2. CONCLUSIONS: In small children without predicted difficult airways, time to intubate the trachea was significantly longer for a McGRATH®MAC blade 1 than a Macintosh blade 1. CLINICAL TRIAL REGISTRATION: jRCT1032220366.

Analysis of Risk Factors for Tracheal Stenosis Managed during COVID-19 Pandemic: A Retrospective, Case-Control Study from Two European Referral Centre.

INTRODUCTION: Benign subglottic/tracheal stenosis (SG/TS) is a life-threatening condition commonly caused by prolonged endotracheal intubation or tracheostomy. Invasive mechanical ventilation was frequently used to manage severe COVID-19, resulting in an increased number of patients with various degrees of residual stenosis following respiratory weaning. The aim of this study was to compare demographics, radiological characteristics, and surgical outcomes between COVID-19 and non-COVID patients treated for tracheal stenosis and investigate the potential differences between the groups. MATERIALS AND METHODS: We retrospectively retrieved electronical medical records of patients managed at two referral centers for airways diseases (IRCCS Humanitas Research Hospital and Avicenne Hospital) with tracheal stenosis between March 2020 and May 2022 and grouped according to SAR-CoV-2 infection status. All patients underwent a radiological and endoscopic evaluation followed by multidisciplinary team consultation. Follow-up was performed through quarterly outpatient consultation. Clinical findings and outcomes were analyzed by using SPPS software. A significance level of 5% (p < 0.05) was adopted for comparisons. RESULTS: A total of 59 patients with a mean age of 56.4 (±13.4) years were surgically managed. Tracheal stenosis was COVID related in 36 (61%) patients. Obesity was frequent in the COVID-19 group (29.7 ± 5.4 vs. 26.9 ± 3, p = 0.043) while no difference was found regarding age, sex, number, and types of comorbidities between the two groups. In the COVID-19 group, orotracheal intubation lasted longer (17.7 ± 14.5 vs. 9.7 ± 5.8 days, p = 0.001), tracheotomy (80%, p = 0.003) as well as re-tracheotomy (6% of cases, p = 0.025) were more frequent and tracheotomy maintenance was longer (21.5 ± 11.9 days, p = 0.006) when compared to the non-COVID group. COVID-19 stenosis was located more distal from vocal folds (3.0 ± 1.86 vs. 1.8 ± 2.03 cm) yet without evidence of a difference (p = 0.07). The number of tracheal rings involved was lower in the non-COVID group (1.7 ± 1 vs. 2.6 ± 0.8 p = 0.001) and stenosis were more frequently managed by rigid bronchoscopy (74% vs. 47%, p = 0.04) when compared to the COVID-19 group. Finally, no difference in recurrence rate was detected between the groups (35% vs. 15%, p = 0.18). CONCLUSIONS: Obesity, a longer time of intubation, tracheostomy, re-tracheostomy, and longer decannulation time occurred more frequently in COVID-related tracheal stenosis. These events may explain the higher number of tracheal rings involved, although we cannot exclude the direct role of SARS-CoV-2 infection in the genesis of tracheal stenosis. Further studies with in vitro/in vivo models will be helpful to better understand the role of inflammatory status caused by SARS-CoV-2 in upper airways.

Diagnostic Dilemma: A Patient With Pulmonary Fibrosis Who Presented for Severe Tracheal Stenosis After COVID-19 Pneumonia.

A 44-year-old man with pulmonary fibrosis presented to our pulmonary hypertension clinic with biphasic stridor and dyspnea. He was sent to the emergency department, where he was found to have 90% subglottic tracheal stenosis and was successfully treated with balloon dilation. Seven months prior to the presentation, he required intubation for coronavirus disease 2019 (COVID-19) pneumonia complicated by hemorrhagic stroke. He was discharged after percutaneous dilatational tracheostomy, which was decannulated after three months. Our patient possessed several risk factors for tracheal stenosis, including endotracheal intubation, tracheostomy, and airway infection. Furthermore, our case is of great importance given the developing literature on COVID-19 pneumonia and its subsequent complications. Additionally, his history of interstitial lung disease may have confounded his presentation. Therefore, it is important to understand stridor, as it is an important exam finding that clinically distinguishes upper and lower airway disease. Our patient's biphasic stridor is consistent with the diagnosis of severe tracheal stenosis.

Bronchoscopy in the post-acute phase of COVID-19: an observational study.

BACKGROUND: Bronchoscopy is a useful technique adopted in the management of patients with COVID-19. 10-40% of COVID-19 survivors experience persistent symptoms. A comprehensive description of the utility and safety of bronchoscopy in the management of patients with COVID-19 sequelae is lacking. The aim of the study was to evaluate the role of bronchoscopy in patients with suspected post-acute sequelae of COVID-19. METHODS: An observational, retrospective study was carried out in Italy. Patients requiring bronchoscopy for suspected COVID-19 sequelae were enrolled. RESULTS: 45 (21, 46.7%, female) patients were recruited. Bronchoscopy was more frequently indicated for patients with a previous critical disease. The most frequent indications were tracheal complications, mostly performed in patients who were hospitalized during the acute phase than treated at home (14, 48.3% VS. 1, 6.3%; p-value: 0.007) and persistent parenchymal infiltrates, more frequent in those treated at home (9, 56.3% VS. 5, 17.2%; p-value: 0.008). 3 (6.6%) patients after the first bronchoscopy required higher oxygen flow. Four patients were diagnosed with lung cancer. CONCLUSION: Bronchoscopy is a useful and safe technique in patients with suspected post-acute sequelae of COVID-19. The severity of acute disease plays a role in the rate and indications of bronchoscopy. Endoscopic procedures were mostly performed for tracheal complications in critical, hospitalized patients and for persistent lung parenchymal infiltrates in mild-moderate infections treated at home.

RAPID IDENTIFICATION OF ETIOLOGICAL AGENTS OF RESPIRATORY TRACT INFECTIONS DURING THE COVID-19 PANDEMIC USING THE MULTIPLEX-PCR METHOD.

Objective. Most respiratory infections have similar symptoms, so it is clinically difficult to determine their etiology. This study aimed to show the importance of molecular diagnostics in identifying the etiological agent of respiratory infections, especially during the coronavirus disease 2019 (COVID-19) pandemic. Methods. A total of 849 samples from patients hospitalized at the University Clinical Center Kragujevac (from January 1 to August 1, 2022) were examined using automated multiplex-polymerase chain reaction (PCR) tests. The BioFire-FilmArray-Respiratory Panel 2.1 test was used for 742 nasopharyngeal swabs [identification of 19 viruses (including SARS-CoV-2) and four bacteria], while the BioFire-FilmArray-Pneumonia Panel was used [identification of 18 bacteria and nine viruses] (BioMerieux, Marcy l'Etoile, France) for 107 tracheal aspirates. The tests were performed according to the manufacturer's instructions, and the results were available within an hour. Results. In 582 (78.4%) samples, the BioFire-FilmArray-Respiratory Panel 2.1 plus test identified at least one pathogen. The rhinovirus (20.6%), SARS-CoV-2 (17.7%), influenza A (17.5%), respiratory syncytial virus (12.4%), and parainfluenza 3 (10.1%) were the most common. Other viruses were found less frequently, and Bordetella parapertussis was detected in one sample. In 85 (79.4%) samples, the BioFire-FilmArray-Pneumonia Panel test identified at least one bacterium or virus. The most prevalent bacteria were Staphylococcus aureus (42.4%), Haemophilus influenzae (41.2%), Streptococcus pneumoniae (36.5%), Moraxella catarrhalis (22.3%), and Legionella pneumophila (2.4%). Among viruses, rhinovirus (36.5%), adenovirus (23.5%), influenza A (11.8%), and the genus Coronavirus (4.7%), were detected. Conclusion. Multiplex-PCR tests improved the implementation of therapeutic and epidemiological measures, preventing the spread of the COVID-19 infection and Legionnaires' disease.Copyright © 2022, Serbian Medical Society. All rights reserved.

Acute stress disorder and post traumatic stress disorder after ICU admission for acute respiratory failure due to COVID-19

Introduction: ICU survivors may present symptoms of acute stress disorder(ASD) or post traumatic stress disorder (PTSD) [1], as defined by the Diagnostic and Statistical Manual of Mental Disorders. Prevalence of PTSD in ARDS affects 20% of survivors but is higher in SARS/ MERS patients [2];risk factors are delirium, ICU sedation, altered memories or ICU amnesia [3]. Method(s): We enrolled patients discharged from our ICU (Pavia-Italy) after admission for acute respiratory failure due to COVID-19. Written consent was collected. Inclusion criteria: age >= 18 years, ICU admission between February 2020 and July 2021 for severe COVID-19, SARSCoV-2 infection confirmed by positive nasal swab/tracheal aspirate, available follow-up visit. Exclusion criteria: refuse to attend the follow up visit, refuse to perform the psychological tests. To assess ASD/ PTSD we used the IES-R: a total mean score >= 33 was the cut-off value for ASD/PTSD;subscale scores for avoidance, intrusion, hyperarousal were calculated. Quantitative and categorical variables are expressed as median [IQR] and number (%). Result(s): Of the 491 patients admitted to ICU, 113 patients were included (males 84(74.3%), age 61.0[52.0-66.0] years, BMI 28.2[25.8- 31.6] kg/m2, SAPS2 31.0[26.0-41.5], ICU stay 17.0[8.0-28.0] days, invasive mechanical ventilation 61(54.0%). They were assessed in median 107.0 [82.0-150.0] days after ICU discharge. 37 patients (32.7%) had ASD/PTSD, higher than the expected 20% in general ARDS population (p < 0.001). Both intrusion 11.0[5.0-17.0] and avoidance 7.0[3.0-13.0] median scores were higher than hyperarousal 5.0[2.0-9.0]. Conclusion(s): ASD/PTSD is frequent after discharge to ICU for severe COVID-19, this prevalence is higher than other ARDS population, maybe for stigma, difficulties with quarantine and isolation. Patients have higher intrusion and avoidance scores, maybe because during the pandemic isolation was unavoidable.

Incidence and microbiological characteristics of ventilator-associated pneumonia assessed by bronchoalveolar lavage and endotracheal aspirate in COVID-19 patients: COV-AP study

Introduction: Diagnosis of ventilator-associated pneumonia (VAP) in COVID-19 patients remains challenging. Also, the lack of gold standard for microbiological sampling undermines clinical judgement and management. We studied incidences of microbiologically-confirmed VAP comparing endotracheal aspirate (ETA) and bronchoalveolar lavage (BAL) in COVID-19 patients. Etiological agreement between ETA and BAL was then assessed. Method(s): Single-center prospective cohort study (NCT04766983). Patients were enrolled within 48 h from intubation;surveillance ETA ( ETASURV) was performed twice weekly. ETA ( ETACX) and BAL ( BALCX) samples were collected upon VAP suspicion (Johanson's criteria). CDC definitions were used for microbiological confirmation. ETA-BAL agreement (interrater reliability and Cohen's kappa) and clinical/microbiological data were assessed for the first episodes of suspected VAP per patients. Result(s): Ninety intensive care (ICU) patients enrolled from 01/2021 to 05 06/2022, of which 26 females (28.9%);median age was 60 [52-66] years. In-ICU mortality was 30/90 (33.3%), median length of stay in survivors 19 (10-32) days. Fifty-three patients (58.9%) had >= 1 episode of suspected VAP after 6 [5;10] days from ICU admission. ETASURV were available in 52 cases, 2 [1;3] days before VAP suspect, and tested positive in 28 (53.8%). ETACX and BALCX resulted positive in 35 (66.0%) and 29 (54.7%) of episodes. Main microbiological results are displayed in Fig. 1, panel A. Etiological agreement between techniques is shown in Fig. 1, panel B. Incidence rate of VAP suspicions per 1000 ventilator-days was 60.2 (95% CI 43.9-76.4), while incidence rates of microbiologically-confirmed VAP were 27.4 (18.3-36.5) with ETACXand 18.9 (95% CI 12.0-25.8) with BALCX, respectively. Conclusion(s): We observed different incidence of VAP in COVID-19 ICU patients depending on sampling method. Etiological agreement between techniques yielded limited interrater reliability. The potential clinical impact needs further studies.

Upper Airway Complications in COVID-19: A Case Series.

Prolonged intubation is associated with several complications leading to upper airway obstruction, including tracheal stenosis and tracheomalacia. Tracheostomy may potentially decrease the risk of tracheal injury in patients with upper airway obstruction. The ideal timing to perform tracheostomy remains controversial. Prolonged intubations were particularly common during the initial phase of the coronavirus disease 2019 (COVID-19) pandemic. This study aimed to present a series of five cases of upper airway complications in patients who underwent mechanical ventilation in the setting of COVID-19 and discuss their clinical aspects, risk factors, and therapeutic strategies.

Laryngotracheal Stenoses Post-Acute Respiratory Distress Syndrome due to COVID-19: Clinical Presentation, Histopathological Findings and Management. A Series of 12 Cases.

Coronavirus disease 2019 (COVID-19) has increased the risk of developing severe acute respiratory distress syndrome and subsequent moderate to severe laryngotracheal stenoses (LSTs) with an early presentation that occurs between two and three months after SARS-CoV-2 infection. We present a series of 12 cases of LST following SARS-CoV-2 infection. Dense lymphocyte infiltration with multinuclear giant cell granulomas was found on biopsy with intranuclear inclusions, suggestive of viral cytopathic effects in one case and intravascular fibrin thrombi with perivascular mononuclear infiltrate of CD3 + T lymphocytes. We present the largest and only series that describes clinical and histopathological characteristics of LTS and the management and outcomes after early laryngotracheal reconstruction in the context of the SARS-CoV-2 outbreak.

Airway management in patients with COVID-19: an updated guide for clinicians in the emergency department

The coronavirus disease, also known as Coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome-coronavirus-2 virus has changed the characteristics of many methods used by healthcare providers. These modifications aimed to provide safety and reduce the risk of virus transmission. Some of the recommendations to reduce the risk of aerosol transmission during the intubation are usage of personal protective equipment (PPE) and video laryngoscopy (VL). After satisfactory preoxygenation, along with sedation and paralysis of the patient, modified rapid sequence induction is the recommended technique. Intubation timing and period should be arranged well in order to minimize aerosol spread. During intubation, barrier devices, such as screens and intubation boxes should be considered. Patient coughing during intubation can generate aerosols and should be avoided. Gentle airway manipulation is assured. It is prudent to use VL rather than direct laryngoscopy for intubation because VL increases the distance between the healthcare worker's face and the patient's face, which may minimize the risk of contamination. In this narrative review, we aimed to focus on protective measures and modifications occurred during COVID-19 pandemic. Copyright (C) 2022 Wolters Kluwer Health, Inc. All rights reserved.

Complicated Laryngotracheal Stenosis Occurring Early after COVID-19 Intubation

Background: Airway stenosis is a known complication of prolonged intubation in hospitalized patients. With the high rate of intubations in patients with COVID-19 pneumonia, laryngotracheal stenosis (LTS) is a complication of COVID-19 that drastically reduces quality of life for patients who may remain tracheostomy-dependent. Methods: Patient medical history, laryngoscopy, and CT imaging were obtained from medical records. Results: We report four cases of complicated LTS following intubation after COVID-19 pneumonia and explore the current literature in a narrative review. Four patients developed LTS following intubation from COVID-19 pneumonia. Three patients remain tracheostomy-dependent, and the fourth required a heroic operative schedule to avoid tracheostomy. Conclusion: Intubation for COVID-19 pneumonia can result in severe LTS, which may persist despite endoscopic intervention. © 2022 by the authors.

Microbiological monitoring of COVID-19 patients in the ICU: a prospective observational study.

Objective. To study spectrum of pathogens and the time to colonization of respiratory samples in patients with severe and critical COVID-19 as well as to analyze incidence of nosocomial infections and structure of prescribed antibacterial drugs. Materials and methods. The prospective observational study included patients aged 18 years and older with confirmed severe and critical COVID-19 from December 2021 to February 2022. During the first 48 hours and then every 2-3 days of hospitalization, a respiratory sample was collected: sputum, tracheal aspirate (if intubated), bronchoalveolar lavage (if bronchoscopy was performed) for microscopy and microbiological examination. Some patients were screened for invasive aspergillosis. Clinical and demographic data, comorbidities, pathogenetic therapy for COVID-19, antibiotic therapy, cases of probable/documented bacterial nosocomial infections, antibiotic-associated diarrhea, and hospital treatment outcomes were recorded. Results. A total of 82 patients were included in this study. Patients with lung parenchyma involvement of more than 50% by computer tomography predominated;most of them (77%) required intubation and mechanical ventilation due to progression of respiratory failure, and 76% of patients had a lethal outcome. During the first 48 hours, a respiratory sample was obtained from 47 patients;the rest of the patients presented with non-productive cough. No growth of microorganisms was detected in 31 (36.8%) cases;clinically significant pathogens were detected in 16 (19.5%) patients. A subsequent analysis included data from 63 patients with a sufficient number of samples for dynamic observation were used. During the first 3 days of ICU stay, the most common bacterial pathogens were Klebsiella pneumoniae without acquired antibiotic resistance and methicillin-susceptible Staphylococcus aureus. From 3rd day and afterwards, an increase in the proportion of Acinetobacter baumannii, other non-fermenting bacteria, and carbapenem-resistant Enterobacterales was noted. Among the pathogens causing lower respiratory tract infections, A. baumannii and carbapenem-resistant K. pneumoniae were predominant pathogens and accounted for 76% of cases. Positive galactomannan test results were obtained in 4 cases. Conclusions. The study confirmed importance of bacterial nosocomial infections in patients with severe and critical COVID-19. In the case of the development of nosocomial lower respiratory tract infections, empirical antimicrobial therapy should take into account the predominance of carbapenem-resistant Enterobacteria and A. baumannii, as well as the possibility of invasive aspergillosis.Copyright © 2022, Interregional Association for Clinical Microbiology and Antimicrobial Chemotherapy. All rights reserved.

A rabbit model of tracheal collapse for optimal self-expanding metal stents.

Investigating the characteristics of tracheas can help the understanding of diseases related to the trachea, particularly tracheal collapse (TC) in dogs. This study aimed to compare the mechanical properties of tracheas from New Zealand White (NZW) rabbits and dogs and to introduce a method for inducing a model of TC in the normal trachea. Tracheal samples were obtained from NZW rabbit cadavers (n=5) weighing 3.62-3.92 kg and from dog cadavers (n=5) weighing 2.97-3.28 kg. Three live NZW rabbits weighing 3.5-4.0 kg were used to establish the model. The radial forces of both sample sets were measured using a digital force gauge and statistically compared. Subsequently, TC was surgically induced in three female NZW rabbits by physically weakening their tracheal cartilage under general anesthesia. Their clinical signs were monitored for 3 months, and radiographic examinations were performed monthly for 3 months. The mean radial forces of the two sample sets were comparable (P>0.05). The clinical signs, radiographic examinations, and macroscopic examinations were all comparable to those of dogs with TC. The cadaveric study between the rabbits and dogs demonstrated that the surgically induced rabbit model of TC is an excellent candidate for the experimental study of dogs with TC. This study also provides a reference of tracheal radial force values to enable selection of appropriate mesh types and wire diameters of self-expanding metal stents.

Tracheal tube cuff pressure during anesthesia for robotic-assisted laparoscopic prostatectomy and the efficacy of an automatic cuff pressure controller (SmartCuff): observational studies of 1-sample paired data.

PURPOSE: The cuff pressure of a tracheal tube may increase during robot-assisted laparoscopic surgery for prostatectomy (RALP), which requires pneumoperitoneum in a steep head-down position, but there have been no studies which confirmed this. METHODS: In study 1, we studied how frequently the cuff pressure significantly increased during anesthesia for the RALP. In study 2, we studied if the SmartCuff (Smiths Medical Japan, Tokyo) automatic cuff pressure controller would minimize the changes in the intracuff pressure. With approval of the study by the research ethics committee (approved number: 20115), we measured the cuff pressures in anesthetized patients undergoing RALP and in those undergoing gynecological laparotomy (as a reference cohort), with and without the use of the SmartCuff. RESULTS: In 21 patients undergoing RALP, a clinically meaningful increase (5 cmH2O or greater) was observed in all the 21 patients (P = 0.00; 95% CI for difference: 86-100%), whereas in 23 patients undergoing gynecological laparotomy, a clinically meaningful decrease (5 cmH2O or greater) was observed in 21 of 23 patients (91%, P < 0.0001; 95% CI for difference: 72-99%). With the use of the SmartCuff, there was no significant increase in the incidence of a clinically meaningful change in the intracuff pressure in either cohort. CONCLUSION: The cuff pressure of a tracheal tube would frequently increase markedly in patients undergoing RALP, whereas it would frequently decrease markedly in patients undergoing gynecological laparotomy. The SmartCuff may inhibit the changes in the cuff pressure during anesthesia.

Not only acute respiratory failure: COVID-19 and the post-intubation/tracheostomy upper airways lesions†.

Background: An increasing number of patients have been subjected to prolonged invasive mechanical ventilation due to COVID-19 infection, leading to a significant number of post-intubation/tracheostomy (PI/T) upper airways lesions. The purpose of this study is to report our early experience in endoscopic and/or surgical management of PI/T upper airways injuries of patients surviving COVID-19 critical illness. Materials and Methods: We prospectively collected data from patients referred to our Thoracic Surgery Unit from March 2020 to February 2022. All patients with suspected or documented PI/T tracheal injuries were evaluated with neck and chest computed tomography and bronchoscopy. Results: Thirteen patients (8 males, 5 females) were included; of these, 10 (76.9%) patients presented with tracheal/laryngotracheal stenosis, 2 (15.4%) with tracheoesophageal fistula (TEF) and 1 (7.7%) with concomitant TEF and stenosis. Age ranged from 37 to 76 years. Three patients with TEF underwent surgical repair by double layer suture of oesophageal defect associated with tracheal resection/anastomosis (1 case) or direct membranous tracheal wall suture (2 cases) and protective tracheostomy with T-tube insertion. One patient underwent redo-surgery after primary failure of oesophageal repair. Among 10 patients with stenosis, two (20.0%) underwent primary laryngotracheal resection/anastomosis, two (20.0%) had undergone multiple endoscopic interventions before referral to our Centre and, at arrival, one underwent emergency tracheostomy and T-tube positioning and one a removal of a previously positioned endotracheal nitinol stent for stenosis/granulation followed by initial laser dilatation and, finally, tracheal resection/anastomosis. Six (60.0%) patients were initially treated with rigid bronchoscopy procedures (laser and/or dilatation). Post-treatment relapse was experienced in 5 (50.0%) cases, requiring repeated rigid bronchoscopy procedures in 1 (10.0%) for definitive resolution of the stenosis and surgery (tracheal resection/anastomosis) in 4 (40.0%). Conclusions: Endoscopic and surgical treatment is curative in the majority of patients and should always be considered in PI/T upper airways lesions after COVID-19 illness.