Gastrointestinal tissue as a "new" target of pollution exposure.

Airborne pollution has become a leading cause of global death in industrialized cities and the exposure to environmental pollutants has been demonstrated to have adverse effects on human health. Among the pollutants, particulate matter (PM) is one of the most toxic and although its exposure has been more commonly correlated with respiratory diseases, gastrointestinal (GI) complications have also been reported as a consequence to PM exposure. Due to its composition, PM is able to exert on intestinal mucosa both direct damaging effects, (by reaching it either via direct ingestion of contaminated food and water or indirect inhalation and consequent macrophagic mucociliary clearance) and indirect ones via generation of systemic inflammation. The relationship between respiratory and GI conditions is well described by the lung-gut axis and more recently, has become even clearer during coronavirus disease 2019 (COVID-19) pandemic, when respiratory symptoms were associated with gastrointestinal conditions. This review aims at pointing out the mechanisms and the models used to evaluate PM induced GI tract damage.

Cuffed versus uncuffed tracheal tubes in a rabbit training model for establishing an emergency front-of-neck airway in infants: a prospective trial.

BACKGROUND: There is a paucity of evidence regarding the optimal type of tracheal tube to be advanced over a Frova catheter when performing a 'bougie' emergency front-of-neck airway (eFONA) technique in infants during a 'cannot intubate, cannot oxygenate' situation. METHODS: A prospective non-inferiority trial in a rabbit cadaver surgical tracheotomy model to assess the performance of the eFONA technique with an uncuffed 3.5 mm ID tracheal tube vs a cuffed 3.0 mm ID tracheal tube. Queried outcomes include success rate, performance time, and severe secondary airway injuries among tracheal tube types. RESULTS: In 60 tracheostomies performed by 30 participants, the overall success rate was 98%. Performance time was independent from tracheal tube choice (uncuffed: 61 s [95% confidence interval (CI), 52-76], cuffed: 64 s [95% CI, 55-79]; P = 0.82). No tracheal tube type was preferred in terms of usability by participants. The cuffed tracheal tube required increased force to be advanced over the Frova catheter and was associated with a risk ratio of 2.5 (95% CI, 0.53-11.9; number needed to harm, 10) for severe secondary airway injuries when compared with the uncuffed tracheal tube. CONCLUSION: In performing eFONA in the rabbit cadaver model, an ID 3.5 uncuffed is non-inferior to an ID 3.0 cuffed tracheal tube regarding performance time and preference by the operator. Greater force application to advance the cuffed tube over the Frova catheter and more severe airway injuries may argue for the standardised performance of the eFONA technique with a uncuffed tracheal tube in infants.

Airway Rupture Caused by Double-Lumen Tubes: A Review of 187 Cases.

The double-lumen tubes (DLTs) are the most widely used devices to provide perioperative lung isolation. Airway rupture is a rare but life-threatening complication of DLTs. The primary aim of this review was to collect all cases reported in the literature about airway rupture caused by DLTs and to describe the reported possible contributors, diagnosis, treatment, and outcomes of this complication. Another aim of this review was to assess the possible factors associated with mortality after airway rupture by DLTs. A comprehensive literature search for all cases of airway rupture caused by DLTs was performed in the PubMed, EMBASE, Ovid, Wanfang Database, and CNKI. The extracted data included age, sex, height, weight, type of operation, type and size of DLT, site of airway rupture, possible contributors, clinical presentation, diagnosis timing, treatment, and outcome. We included 105 single case reports and 22 case series with a total number of 187 patients. Most of the ruptures were in the trachea (n = 98, 52.4%) and left main bronchus (n = 70, 37.4%). The common possible contributors include use of a stylet, cuff overdistention, multiple attempts to adjust the position of a DLT, difficult intubation, and use of an oversized DLT. Most of the airway ruptures were diagnosed intraoperatively (n = 138, 82.7%). Pneumomediastinum, air leakage, hypoxemia, and subcutaneous emphysema were the common clinical manifestations. Most patients were treated with surgical repair (n = 147, 78.6%). The mortality of the patients with airway rupture by DLTs was 8.8%. Age, sex, site of rupture, diagnosis timing, and method of treatment were not found to be associated with mortality.

National estimations of airway foreign bodies in children in the United States, 2000 to 2009.

OBJECTIVE: Identify risk factors associated with airway foreign bodies in children in the United States and report observed trends over time. DATA SOURCE: KID database (2000-2009). METHODS: ICD-9-CM codes for airway foreign bodies were used to identify patients. Risk factors were used for univariate analysis and a multivariate model to identify any increased risk of mortality. These factors were then also trended over time. RESULTS: Children with airway foreign bodies demonstrate similar risk factors as previously reported, such as male gender, age less than five years and lack of private insurance. The weighted mortality rate for paediatric inpatients with airway foreign bodies was about 2.75%. Fortunately, the rate remained relatively unchanged from 2000 to 2009. Geographically, urban hospital settings appeared to be more affected. Increased risks of mortality were noted for older age, urban hospital setting and teaching hospital status. CONCLUSIONS: Our findings confirm previous findings and identified that the diagnosis of airway foreign bodies in children were associated with male gender, age <5 years, lack of private insurance and geographic location in an urban setting. Further investigation may be warranted to provide clarity on other factors found to have increased association with mortality for quality improvement.

Host protective roles of type 2 immunity: parasite killing and tissue repair, flip sides of the same coin.

Metazoan parasites typically induce a type 2 immune response, characterized by T helper 2 (Th2) cells that produce the cytokines IL-4, IL-5 and IL-13 among others. The type 2 response is host protective, reducing the number of parasites either through direct killing in the tissues, or expulsion from the intestine. Type 2 immunity also protects the host against damage mediated by these large extracellular parasites as they migrate through the body. At the center of both the innate and adaptive type 2 immune response, is the IL-4Rα that mediates many of the key effector functions. Here we highlight the striking overlap between the molecules, cells and pathways that mediate both parasite control and tissue repair. We have proposed that adaptive Th2 immunity evolved out of our innate repair pathways to mediate both accelerated repair and parasite control in the face of continual assault from multicellular pathogens. Type 2 cytokines are involved in many aspects of mammalian physiology independent of helminth infection. Therefore understanding the evolutionary relationship between helminth killing and tissue repair should provide new insight into immune mechanisms of tissue protection in the face of physical injury.

Airway foreign bodies in pediatric patients: anatomic location of foreign body affects complications and outcomes.

BACKGROUND: Airway foreign bodies (FB) are a common medical emergency within the pediatric population. While deaths are not uncommon, the in-hospital mortality rates and correlation with anatomic location of the airway foreign body have not been previously reported. METHODS: The KID database was reviewed for 2003, 2006, 2009, and 2012 for pediatric patients with a discharge diagnosis of airway foreign body using ICD-9 codes (933.1, 934.x). RESULTS: 11,793 patients, ages 0-17, were found to have an airway FB. Of patients admitted for airway FB 21.2 % required mechanical ventilation during their hospitalization, and the overall mortality rate was 2.5 %. Location of the airway FB was dependent on age (p < 0.01). Use of mechanical ventilation was dependent on the location of the airway FB (p < 0.01) and being transferred from another hospital (OR 2.59, p < 0.01). Univariate analysis demonstrated differences in in-hospital mortality based on location (p < 0.01), use of a ventilator during hospitalization (OR 24.4, p < 0.01), and transfer from another hospital (OR 2.11, p < 0.01). CONCLUSIONS: The in-hospital mortality rate for airway foreign bodies is 2.5 %. The anatomic location of airway FB in pediatric patients varies by age, and affects the need for mechanical ventilation and in-hospital mortality.

[INJURY PREVENTION WHILE ENSURING THE AIRWAY DURING SURGERY IN THE NOSE AND SINUSES.]

THE AIM: A comparative analysis of the injuries of upper airways flexible reinforced laryngeal mask and endotracheal intubation by examining the stress response reaction of the cardiovascular system, as well as the frequency and variety of complications. Blood pressure, heart rate, glucose and cortisol, and complications of airway management in children were analyzed. METHODS: The influence of the method of airway management with surgery in nose and sinuses in children in the stress response, hemodynamics, injuries of the airway were studied. The study included 140 patients aged 3 to 17 years. RESULTS: LMA FlexibleTMhas a minimal negative impact on the hemodynamics. Stress response is less pronounced when installing laryngeal mask than with tracheal intubation, which manifests itself in less cortisol concentration of 3.7%, 11.4% glucose. After removing the flexible reinforced laryngeal mask less than after extubation occurs: cough by 21%, 10% hoarseness, and sore throat by 26%. CONCLUSION: The use of the laryngeal mask airway during surgery in the nose and paranasal sinuses safer and less trau- matic manipulation compared with tracheal intubation.

Penetrating aerodigestive injuries in the neck: a proposed CT-aided modified selective management algorithm.

OBJECTIVES: To determine the specific CT findings of penetrating neck wound profile predicting aerodigestive injuries, diagnostic performance of CTA and to propose a modified selective management algorithm to reduce nontherapeutic invasive procedures. METHODS: We retrospectively evaluated CTAs of 102 patients to determine the presence of various CT signs. "Trajectory"-based signs included trajectory of the wound extending into the aerodigestive tract and trajectory violating the deep neck spaces. "Conventional" signs included transcervical injury; wall defect; air or blood in the deep neck spaces; irregular or thickened aerodigestive tract; and active mucosal bleeding. RESULTS: Trajectory of the wound extending into the aerodigestive tract (sensitivity 76 %, specificity 97 %) and trajectory of the wound violating the suprahyoid deep neck spaces or the infrahyoid visceral space (sensitivity 97 %, specificity 55 %) were the best predictors of injury on regression analysis. The most specific "conventional" CT signs were "wall defect" and "active mucosal bleed", but had very low sensitivity. The sensitivity of CTA for detecting an injury ranged from 89.5 % to 92 %, specificity ranged from 62.5 % to 89 %. CONCLUSION: CTA can be a useful technique in detecting aerodigestive injury. Our proposed management algorithm can exclude an injury with high degree of confidence (sensitivity 97 %). KEY POINTS: • Trajectory-based CT signs predict aerodigestive injury after penetrating neck trauma. • Surgery should be considered when trajectory extends into the infra-arytenoid aerodigestive tract. • Endoscopy or exploration should be considered when trajectory violates deep neck spaces. • This modified approach can decrease negative explorations and invasive diagnostic procedures.

Systematic review of the anaesthetic management of non-iatrogenic acute adult airway trauma.

INTRODUCTION: Non-iatrogenic trauma to the airway is rare and presents a significant challenge to the anaesthetist. Although guidelines for the management of the unanticipated difficult airway have been published, these do not make provision for the 'anticipated' difficult airway. This systematic review aims to inform best practice and suggest management options for different injury patterns. METHODS: A literature search was conducted using Embase, Medline, and Google Scholar for papers after the year 2000 reporting on the acute airway management of adult patients who suffered airway trauma. Our protocol and search strategy are registered with and published by PROSPERO (http://www.crd.york.ac.uk/PROSPERO, ID: CRD42016032763). RESULTS: A systematic literature search yielded 578 articles, of which a total of 148 full-text papers were reviewed. We present our results categorized by mechanism of injury: blunt, penetrating, blast, and burns. CONCLUSIONS: The hallmark of airway management with trauma to the airway is the maintenance of spontaneous ventilation, intubation under direct vision to avoid the creation of a false passage, and the avoidance of both intermittent positive pressure ventilation and cricoid pressure (the latter for laryngotracheal trauma only) during a rapid sequence induction. Management depends on available resources and time to perform airway assessment, investigations, and intervention (patients will be classified into one of three categories: no time, some time, or adequate time). Human factors, particularly the development of a shared mental model amongst the trauma team, are vital to mitigate risk and improve patient safety.

Civilian Airway Trauma: A Single-Institution Experience.

BACKGROUND: Injuries to the airway in the neck and thorax are uncommon, but may be potentially life threatening. The objective of this study is to determine the clinical characteristics and outcomes for patients with airway injury. METHODS: From 1974 to 2014, a prospectively entered trauma database at a Level 1 trauma center was accessed to identify patients with injuries to the larynx, cervical trachea, or thoracic airway. Hospital charts were reviewed to obtain data on demographics, presentation, injury management, in-hospital and long-term morbidity and in-hospital mortality. Multivariate logistic regression was used to estimate predictors of mortality and long-term vocal cord morbidity. Data are expressed as N (%). RESULTS: One hundred and twenty patients were included (median injury severity score: 19 [interquartile range: 10-27]). There were 65 (54 %) blunt and 55 (46 %) penetrating injuries, with 90 (75 %) suffering multiple injuries. Sixteen (13 %) patients died from associated injuries (7: in ER; 9: after admission). Injuries were located in the cervical airway [101 (84 %)], thoracic airway [21 (18 %)], or both [2 (2 %)]. Eighty-six (72 %) patients were managed surgically. Predictors of in-hospital mortality included hemodynamic instability (OR 6.54, 95 % CI 1.11-37.14), GCS < 8 upon presentation (OR 4.35, 95 % CI 3.24-5.41), and head trauma (OR 4.10, 95 % CI 1.91-6.30). Fracture of cricoid or thyroid cartilages was a strong predictor of long-term vocal cord injury (OR 3.93, 95 % CI 1.25-12.59). CONCLUSIONS: Airway trauma remains a major challenge for early diagnosis, airway control, and management of both acute life-threatening injury and long-term morbidity.

Toxic exposure to caustics and respiratory irritants.

Toxic exposure to caustics and respiratory irritants. Toxic emergencies for which the ENT physician is con- sulted mainly involve toxic exposure of the upper airway and digestive tract to caustics and respiratory irritants. The ENT physician may, however, also be involved as a first responder in the case of poisoned patients. This article therefore aims to provide a comprehensive general approach to patients with suspected poisoning and to present a more elaborate discussion on the diagnosis and management of patients following exposure to caustics and respiratory irritants. This survey, however, does not intend to be a substitute for the need for consultation with an emergency physician and a clinical toxicologist qualified in the diagnosis and treatment of poisoned patients.

[The effect and injury to the airways of different sputum aspiration pressure in a rat model of mucus hypersecretion].

OBJECTIVE: To explore the optimal pressure of sputum aspiration to ensure the effectiveness and safety of clinical operation. METHODS: We established a rabbit model of airway mucus hypersecretion by aerosol acrolein inhalation, and the animals were divided into 4 groups randomly with different sputum aspiration pressure as follows: group A -75 mmHg (1 mmHg=0.133 kPa), group B -150 mmHg, group C -225 mmHg, group D -300 mmHg. Sputum aspiration efficiency and tracheal mucosal damage degree were evaluated by sputum volume, oxygen saturation changes, the pathological sections of tracheal mucosa and the expressions of IL-1ß and TNF-α in airway secretion. RESULTS: The sputum suction volume of group A, B, C, D were (2.72±0.24), (4.81±0.32), (5.03±0.37) and (6.29±0.51) ml, respectively, which was significantly higher in group D, but lower in group A, as compared to other groups (P<0.05). There were no significant differences between B and C groups. The maximal SpO2 decrease of C and D groups [(18.1±5.2)% and(32.4±8.4)%]were significantly higher than those in A and B groups [(4.4±1.7)% and (6.3±2.9)%], and group D was significantly more than group C, and the difference was statistically significant (P<0.05). There were no significant differences between A and B groups. HE staining of tracheal mucosa in C and D groups showed that the inflammatory cell infiltration and mucosal damage were more serious than A and B groups, but the airway mucosal damage of group A was the least. CONCLUSION: The pressure of -150 mmHg was more effective with high oxygen saturation and less airway injury, which may be suitable for clinical sputum aspiration.

Intubation with VivaSight or conventional left-sided double-lumen tubes: a randomized trial.

INTRODUCTION: Double-lumen endotracheal tubes (DLTs), which are commonly used for single-lung ventilation during surgery, are difficult to insert. In addition, they often move during surgical lung manipulation which can cause life-threatening complications. Flexible bronchoscopy is used routinely to establish and confirm proper DLT placement. The newly designed VivaSight DLT has an integrated camera, allowing continuous visualization of its position in the trachea. We hypothesized that the time to intubation using the VivaSight DLT would be faster than with a conventional DLT. METHODS: We enrolled 40 adults scheduled for thoracic surgery. Patients were randomized to conventional DLT (n = 20) or VivaSight DLT (n = 20). Time to intubation was our primary outcome. Secondary outcomes were insertion success without flexible bronchoscopy, frequency of tube displacement, ease of insertion, quality of lung collapse, postoperative complaints, and airway injuries. RESULTS: Time [mean (SD)] to successful intubation was significantly faster with the VivaSight DLT [63 (58) sec] compared with the conventional DLT [97 (84) sec; P = 0.03]. The VivaSight DLTs were correctly inserted during all attempts. When malpositioning of the VivaSight DLT occurred, it was easily remedied, even in the lateral position. The devices were comparable with respect to postoperative coughing, hoarseness, and sore throat. Airway injuries tended to be more common with the VivaSight DLT, although this study was underpowered for airway injuries. CONCLUSION: The VivaSight DLT camera allowed faster insertion and facilitated initial positioning. It also confirmed proper tube positioning intraoperatively and facilitated repositioning when necessary. This trial was registered at clinicaltrials.gov: NCT01807676.

Adverse airway events in parturient compared with non-parturient patients. Is there a difference? Results from a quality management project.

AIM: The fear of airway problems often leads to prolonged attempts to obtain neuroaxial (spinal anesthesia or epidural anesthesia) anesthesia in obstetric anesthesia. The aim of this institutional quality management study was to revisit existing anesthesia care in the obstetric department, focusing on the frequency of delayed or failed neuroaxial anesthesia as well as the risk of airway problems in parturient and non-obstetric patients. METHODS: The clinical records from 8 consecutive years (2005-2013) were analyzed retrospectively. Cases of cesarean delivery with general anesthesia were analyzed and compared with an age-matched group of female patients undergoing non-obstetric abdominal or gynecological surgery with rapid sequence induction. Poor laryngeal visualization (Cormack-Lehane grade III or IV) and failed intubation were recorded. RESULTS: The records of 6393 cesarean deliveries including 851 with general anesthesia were analyzed. In 175 cases insufficient or delayed onset of regional anesthesia led to requirement for general anesthesia. The rate of poor laryngoscopic view in parturient women undergoing cesarean delivery was 14/851, and 4/814 in the reference group (P = 0.023). Failed intubation occurred in three patients undergoing cesarean delivery (0.4%) and in one non-obstetric patient (0.1%; P = 0.339). CONCLUSION: The rate of failed intubations in patients undergoing cesarean delivery may be equivalent to non-obstetric patients. In time-challenging cesarean deliveries, delay of conversion from non-successful neuroaxial anesthesia to general anesthesia in order to avoid adverse airway events does not appear to be justified.

Toxic inhalational exposures.

Respirable toxicants are a spectrum of irritant and nonirritant gases, vapors, fumes, and airborne particles that can be entrained into the body through the respiratory tract, resulting in exposures that cause pulmonary injury and/or systemic disease. Sources of respirable toxicants include structural fires, industrial accidents, domestic mishaps, and intentional releases of injurious agents on the battleground (warfare) or in civilian settings (acts of terrorism). Acute toxic inhalational exposures may result in respiratory failure, multisystem organ dysfunction, and death. Management of victims includes assessment and protection of the airway, monitoring and treatment of systemic toxicity, and delivery of exposure-specific and nonspecific therapies that improve outcomes. Treatments may include antidotes, hyperbaric oxygen, and other nonspecific life-supporting interventions.

Airway trauma in a high patient volume academic cardiac electrophysiology laboratory center.

BACKGROUND: Providing anesthesia and managing airways in the electrophysiology suite can be challenging because of its unique setting outside of the conventional operating room. We report our experience of several cases of reported airway trauma including tongue and pharyngeal hematoma and vocal cord paralysis in this setting. METHODS: We analyzed all of the reported airway trauma cases between December 2009 and January 2011 in our cardiac electrophysiology laboratories and compared these cases with those without airway trauma. Data from 87 cases, including 16 cases with reported airway trauma (trauma group) and 71 cases without reported airway trauma from the same patient population pool at the same period (control group), were collected via review of medical records. RESULTS: Airway trauma was reported for 16 patients (0.7%) in 14 months among 2434 anesthetic cases. None of these patients had life-threatening airway obstruction. The avoidance of muscle relaxants during induction in patients with a body mass index less than 30 was found to be a significant risk factor for airway trauma (P = 0.04; odds ratio, 10; 95% confidence interval, 1.1-482). Tongue or soft tissue bite occurred in 2 cases where soft bite block was not used during cardioversion. No statistically significant difference was found between the trauma and the control groups for preprocedure anticoagulation, anticoagulation during the procedure, or reversal of heparin at the end of the procedure. CONCLUSIONS: The overall incidence of reported airway trauma was 0.7% in our study population. Tongue injury was the most common airway trauma. The cause seems to have been multifactorial; however, airway management without muscle relaxant emerged as a potential risk factor. Intubation with muscle relaxant is recommended, as is placing a soft bite block and ensuring no soft tissue is between the teeth before cardioversion.

BrdU pulse labelling in vivo to characterise cell proliferation during regeneration and repair following injury to the airway wall in sheep.

The response of S-phase cells labelled with bromodeoxyuridine (BrdU) in sheep airways undergoing repair in response to endobronchial brush biopsy was investigated in this study. Separate sites within the airway tree of anaesthetised sheep were biopsied at intervals prior to pulse labelling with BrdU, which was administered one hour prior to euthanasia. Both brushed and spatially disparate unbrushed (control) sites were carefully mapped, dissected, and processed to facilitate histological analysis of BrdU labelling. Our study indicated that the number and location of BrdU-labelled cells varied according to the age of the repairing injury. There was little evidence of cell proliferation in either control airway tissues or airway tissues examined six hours after injury. However, by days 1 and 3, BrdU-labelled cells were increased in number in the airway wall, both at the damaged site and in the regions flanking either side of the injury. Thereafter, cell proliferative activity largely declined by day 7 after injury, when consistent evidence of remodelling in the airway wall could be appreciated. This study successfully demonstrated the effectiveness of in vivo pulse labelling in tracking cell proliferation during repair which has a potential value in exploring the therapeutic utility of stem cell approaches in relevant lung disease models.

Management of penetrating neck injuries.

BACKGROUND: Routine surgical exploration after penetrating neck injury (PNI) leads to a large number of negative neck explorations and potential iatrogenic injury. Selective non-operative management (SNOM) of PNI is gaining favour. The present study assessed the feasibility of SNOM in PNI. METHODS: Seventy-seven consecutive patients with PNI presenting to a tertiary trauma centre were included in this prospective study from September 2009 to December 2009. All patients were managed according to Advanced Trauma Life Support guidelines, and either underwent emergency surgery or were managed without surgery, based on clinical presentation and/or outcome of special investigations. RESULTS: Eight patients (10 per cent) were haemodynamically unstable at presentation. Foley catheter balloon tamponade (FCBT) was successful in stopping active bleeding in six of these patients, and diagnostic angiography revealed an arterial injury in five. The remaining 69 patients were managed using SNOM. Angiography or computed tomography was done in 41 patients (53 per cent), and showed arterial injury in 15. These injuries were treated surgically (7 patients), radiologically (stenting in 3) or conservatively. Contrast swallow and/or endoscopy were performed in 37 patients (48 per cent) for suspected oesophageal injury, but yielded no positive results. During follow-up no missed injuries were detected. CONCLUSION: FCBT was useful in patients with PNI and active bleeding. Stable patients should undergo additional investigation based on clinical findings only.