Management of tracheal stenosis after corrosive acid ingestion: A case report.

Although corrosive injury of the digestive tract is a well-known clinical entity, damages of the airway and a critically life-threatening condition, have not been clearly documented. Tracheal stenosis is very rare associated with corrosive acid ingestion. We report the case of a 4-year-old girl child who presented to the emergency department three weeks after accidentally drinking an acidic cleaning agent stored in an unlabeled bottle. Rigid bronchoscopy was administered to observe the stenosis. She was treated by serial dilation, repair of tracheal laceration, and placement of a temporary polyurethane-coated nitinol stent. Careful and accurate stent placement may provide significant and life-saving airway improvement as observed in the presenting pediatric case.

Glutamine Inhibition Reduces Iatrogenic Laryngotracheal Stenosis.

OBJECTIVE/HYPOTHESIS: Glutamine inhibition has been demonstrated an antifibrotic effect in iatrogenic laryngotracheal stenosis (iLTS) scar fibroblasts in vitro. We hypothesize that broadly active glutamine antagonist, DON will reduce collagen formation and fibrosis-associated gene expression in iLTS mice. STUDY DESIGN: Prospective controlled animal study. METHODS: iLTS in mice were induced by chemomechanical injury of the trachea using a bleomycin-coated wire brush. PBS or DON (1.3 mg/kg) were administered by intraperitoneal injection (i.p.) every other day. Laryngotracheal complexes were harvested at days 7 and 14 after the initiation of DON treatment for the measurement of lamina propria thickness, trichrome stain, immunofluorescence staining of collagen 1, and fibrosis-associated gene expression. RESULTS: The study demonstrated that DON treatment reduced lamina propria thickness (P = .025) and collagen formation in trichrome stain and immunofluorescence staining of collagen 1. In addition, DON decreased fibrosis-associated gene expression in iLTS mice. At day 7, DON inhibited Col1a1 (P < .0001), Col3a1 (P = .0046), Col5a1 (P < .0001), and Tgfß (P = .023) expression. At day 14, DON reduced Co1a1 (P = .0076) and Tgfß (P = .023) expression. CONCLUSIONS: Broadly active glutamine antagonist, DON, significantly reduces fibrosis in iLTS mice. These results suggest that the concept of glutamine inhibition may be a therapeutic option to reduce fibrosis in the laryngotracheal stenosis. LEVEL OF EVIDENCE: N/A Laryngoscope, 131:E2125-E2130, 2021.

Relaxant effects of Peperomia hispidula (Sw.) A. Dietr. on isolated rat tracheal rings / Efecto relajante de Peperomia hispidula (Sw.) A. Dietr. sobre anillos aislados de tráquea de rata

Peperomia hispidula (Sw.) A. Dietr. is used in Mexican traditional medicine for treating respiratory illnesses such as asthma. The latter disorder results from an excessive and inappropriate constriction of airway smooth muscle. The aim of the present study was to evaluate the relaxant activity of P. hispidula on isolated rat tracheal rings contracted with carbachol. The methyleugenol was identified as the main active constituent in the dichloromethane extract. To explore the possible mechanism of action, concentration-response curves were constructed in the presence and absence of propranolol (3 µM), indomethacin (10 µM), glibenclamide (1 µM), and L-NAME (300 µM), finding that neither reduced methyleugenol-induced smooth muscle relaxation. In conclusion, P. hispidula herein displayed relaxant activity on rat tracheal rings. The effect of methyleugenol, was probably not related to the activation of ß2-adrenoceptors, prostaglandins, K+ATP channels or nitric oxide.

Peperomia hispidula (Sw.) A. Dietr. es utilizada en la medicina tradicional mexicana para tratar enfermedades respiratorias como el asma. Este último trastorno es el resultado de una contracción excesiva e inapropiada del músculo liso de las vías respiratorias. El objetivo del presente estudio fue evaluar la actividad relajante de P. hispidula sobre anillos aislados de tráquea de rata contraídos con carbacol. El metileugenol fue identificado como el principal constituyente activo en el extracto de diclorometano. Para explorar el posible mecanismo de acción, se construyeron curvas concentración-respuesta en presencia y ausencia de propranolol (3 µM), indometacina (10 µM), glibenclamida (1 µM), y L-NAME (300 µM), encontrando que ninguno redujo la relajación del músculo liso inducida por metileugenol. En conclusión, P. hispidula muestra actividad relajante en anillos de tráquea de rata. El efecto de metileugenol, al parecer no está implicado con la activación de los receptores ß2-adrenérgicos, prostaglandinas, canales de K+ATP u óxido nítrico.

Tracheoplasty With Use of an Intercostal Muscle Flap for Caustic Necrosis.

We report a case of intercostal muscle flap used in tracheobronchial reconstruction for extensive necrosis after burn lesions of the posterior wall. A 32-year-old man attempted suicide by ingestion of caustic material. He underwent emergency total esogastrectomy, tracheostomy, and feeding jejunostomy. Ten days later, endoscopy showed complete destruction of the membranous trachea, extending from the tracheostomy to the carina. Reconstruction was conducted with the patient under venovenous extracorporeal membrane oxygenation by use of a pedicled intercostal muscle flap. The patient was weaned from respiratory support on the 14th postoperative day. Examination of a biopsy specimen from the flap 7 months after tracheoplasty showed ciliated neoepithelium.

Dysregulated Macrophages Are Present in Bleomycin-Induced Murine Laryngotracheal Stenosis.

OBJECTIVE: To define the inflammatory cell infiltrate preceding fibrosis in a laryngotracheal stenosis (LTS) murine model. STUDY DESIGN: Prospective controlled murine study. SETTING: Laboratory. SUBJECTS AND METHODS: Chemomechanical injury mice (n = 44) sustained bleomycin-coated wire-brush injury to the laryngotracheal complex while mechanical injury controls (n = 42) underwent phosphate-buffered saline (PBS)-coated wire-brush injury. Mock surgery controls (n = 34) underwent anterior transcervical tracheal exposure only. Inflammatory and fibrosis protein and gene expression were assessed in each condition. Immunohistochemistry served as a secondary outcome. RESULTS: In chemomechanical injury mice, there was an upregulation of collagen I (P < .0001, P < .0001), Tgf-ß (P = .0023, P = .0008), and elastin (P < .0001, P < .0001) on day 7; acute inflammatory gene Il1ß (P = .0027, P = .0008) on day 1; and macrophage gene CD11b (P = .0026, P = .0033) on day 1 vs mechanical and mock controls, respectively. M1 marker inducible nitric oxide synthase (iNOS) expression decreased (P = .0014) while M2 marker Arg1 (P = .0002) increased on day 7 compared with mechanical controls. Flow cytometry demonstrated increased macrophages (P = .0058, day 4) and M1 macrophages (P = .0148, day 4; P = .0343, day 7; P = .0229, day 10) compared to mock controls. There were similarities between chemomechanical and mechanical injury mice with an increase in M2 macrophages at day 10 (P = .0196). CONCLUSIONS: The bleomycin-induced LTS mouse model demonstrated increased macrophages involved with the development of fibrosis. Macrophage immunophenotype suggested that dysregulated M2 macrophages have a role in abnormal laryngotracheal wound healing. These data delineate inflammatory cells and signaling pathways in LTS that may potentially be modulated to lessen fibroblast proliferation and collagen deposition.

Long-term management of extensive tracheal stenosis due to formic acid chemical burn.

We report on a 26-year-old woman who during early infancy (6 months) suffered from a chemical burn of the skin and upper airways due to spill of formic acid powder. Twenty years after the initial injury, she presented with dyspnea and stridor due to severe tracheal stenosis. Several interventional bronchoscopic manipulations were initiated: incision of the stenotic lesion with Nd:YAG laser and dilatation with a valvuloplasty balloon which enabled silicone stent placement which was subsequently kept in place for 3 years. Complications during the 4th year after stenting led to the successful replacement of this stent by two autoexpandable metallic stents covering the total length of the trachea from the subglottic area to the carina. In post-burn inhalation injuries, a complex inflammatory process may be active for many years after the initial insult. These injuries respond to prolonged tracheal stenting and a conservative approach is recommended.

Tracheobronchial stenosis following sulfur mustard inhalation.

Sulfur mustard inhalation leads to different respiratory complications. In this article, we describe late stenotic effects of mustard gas inhalation on major airways. About 15 yr after exposure, suspect cases suffering from severe respiratory disorders underwent complete workup for central airway stenosis. Patients were evaluated with bronchoscopy and tracheal computerized tomography scan. The mean age of patients was 43+/-8 yr. The mean exposure time was 16+/-0.7 yr. The mean time between injury and diagnosis of tracheobronchial stenosis was 11.7+/-4.8 yr. Among the 33 referred cases with no other risk factor of stenosis, 8 cases had significant stenosis in their major airways, confirmed by tracheal computerized tomography scan and bronchoscopy. We conclude that direct toxic effects of sulfur mustard can lead to tracheobronchial stenosis with different degrees of involvement ranging from diffuse tracheal stenosis to stenosis of the isolated left main bronchus or glottic and subglottic stenosis.

The presence of working memory without explicit recall in a critically ill patient.

UNLABELLED: We describe an intubated patient sedated with propofol who interacted with caregivers, demonstrating intact "working memory." When neuromuscular blockade and bispectral index (BIS) monitoring were instituted, a greatly reduced amount of sedative achieved BIS values less than 60. Neither the sedation that allowed working memory nor the lighter sedation that produced BIS values less than 60 resulted in recall. This experience suggests that working memory demonstrated when BIS values are less than 60 is unlikely to lead to recall. IMPLICATIONS: The presence of intact working memory during sedation is a poor predictor of explicit recall when bispectral index values are maintained less than 60.

Tracheobronchial stenosis from acid aspiration presenting as asthma.

We report a case of a 42-year-old man who fell in a vat of hydrochloric acid, resulting in ingestion and aspiration of acid. Initially, he suffered from a chemical pneumonitis and GI burns. He was released from the hospital without complications, only to return with signs and symptoms consistent with asthma. Evaluation revealed multiple areas of large airway stenosis, resulting from the chemical burns. The stenoses were treated with multiple stents.

[A fatal case of anaphylactoid shock after administration of nonionic contrast medium].

We report a case of fatal anaphylactoid shock caused by a CT examination using nonionic contrast medium. A 79-year-old female patient was diagnosed with right recurrent nerve plasy. There was no known history of drug allergy or exposure to contrast medium. Approximately 50 seconds after contrast medium bolus injection began, the patient was noted to be apneic. Despite cardiopulmonary resucitation, the patient died. An autopsy demonstrated marked laryngeal edema and showed extensive mast cell infiltration.

Upper airway compromise after inhalation injury. Complex strictures of the larynx and trachea and their management.

OBJECTIVE: Strictures of the upper airway caused by burns have features distinct from other benign stenoses. The authors reviewed their experience with burn-related stenoses to define the principles of treatment. SUMMARY BACKGROUND DATA: The combined effects of inhaled gases and heat in burn victims produce an intense, often transmural, inflammation of the airway, further complicated by intubation. The incidence of laryngotracheal strictures in survivors of inhalation injury is high, but the reported experience with their treatment is limited and often unduly separated into injuries of larynx and trachea. METHODS: Presentation, treatment, and long-term follow-up are reviewed in 9 women and 9 men age 9 to 63 years, who were evaluated over a 22 year period for chronic airway compromise after inhalation injury. There were 18 tracheal stenoses, 14 subglottic strictures, and 2 main bronchial stenoses. Laryngotracheal strictures stenosis. T-tubes were placed in 15 patients, in low subglottic or tracheal stenosis below the vocal cords, in high subglottic stenosis through the vocal cords, and as a stent after resection of subglottic stenosis. RESULTS: There were two deaths during follow-up, one from respiratory failure and one from an unrelated cause. Two patients underwent evaluation only. Early in this series, one tracheal and one laryngotracheal resection resulted in prompt restenosis. Of the remaining 14 patients, 9 are without airway support from 2 to 20 years later. Four have permanent tracheal tubes. One patient required tracheostomy 8 years after successful subglottic reconstruction. CONCLUSIONS: Strictures of the upper airway related to inhalation injury are associated with prolonged inflammation and involve larynx and trachea in a majority of patients. These complex injuries respond to prolonged tracheal stenting (mean, 28 months) and resection or stenting of subglottic stenoses with recovery of a functional airway and voice in most patients. Early tracheal resection should be avoided.

Subglottic stenosis in Wegener's granulomatosis: development during cyclophosphamide treatment with response to carbon dioxide laser therapy.

A patient with Wegener's granulomatosis rapidly developed a circumferential subglottic stenosis while on a cyclophosphamide regimen that had caused resolution of systemic symptoms and pulmonary infiltrates. The stenosis developed in the area of previously noted tracheal ulceration and responded satisfactorily to carbon dioxide laser therapy.

The tracheal nonadrenergic noncholinergic inhibitory system during antigen challenge.

This study was undertaken to test the hypothesis that malfunction of the nonadrenergic noncholinergic inhibitory system (NANCIS) induces hyperreactive airways. Antigen sensitized guinea pigs were divided into four groups: (1) antigen challenge (n = 6), (2) 2 min oxyhemoglobin (HbO2) + antigen challenge (n = 5), (3) 27 min HbO2 + antigen challenge (n = 4), and (4) 2 min HbO2 + transmural stimulation (TS) + antigen challenge (n = 6). These animals were sensitized with ovalbumin 10 days before the study. In addition, 12 normal control animals without antigen sensitization were used for comparison. Under artificial ventilation, the anesthetized-paralyzed animals were hourly injected with atropine (0.2 mg/kg) and propranolol (1 mg/kg). Cervical segment of the trachea was converted to a closed tracheal pouch filled with Krebs solution containing also atropine (1 microM) and propranolol (3.5 microM). A change in the pouch pressure (Pp) reflected NANCIS TS- or antigen (5 micrograms) challenge-induced relaxation and/or constriction. HbO2 was used to inhibit NANCIS transmitter. There was no significant difference between normal and sensitized animals in the NANCIS TS-induced relaxation. Antigen challenge resulted in biphasic alteration in Pp, an initial increase and then a decrease after about 7 min. HbO2 pretreatment alone did not potentiate antigen-induced increase in Pp. HbO2 + TS, however, significantly abolished the late relaxation phase after antigen challenge.

Near-fatal complication of tracheal T-tube use.

Stenosis of the larynx and trachea is an unfortunate sequel to many thermal injuries. Numerous surgical techniques have been developed for correction of such problems, many involving use of a tracheal T-tube. We report a serious complication attributed to the use of such a tube. Factors contributing to this complication are analyzed and methods for avoiding similar near-catastrophes discussed.

[Possible embryofetopathy caused by beta-blocker (sotalol) taken throughout the pregnancy]. / Possible embryofoetopathie par betabloquant (sotalol) pris pendant toute la grossesse.

The authors envisage the hypothesis of an embryofetal intoxication by a beta-blocker (B-), sotalol, taken by the mother, not hypertensive, during all her pregnancy (160 mg/day). The fullterm newborn, hypotrophic and hypothermic, is suffering from facial dysmorphy with microcephaly, and present a severe tracheal stenosis associated with cardiopathy and important rhythm disorders: bradycardia and permanent bigeminate ventricular extrasystoles for three days. Course is fatal at five months old. On the occasion of this probable intoxication, a brief recall about pharmacology and physiopathology of transplacental passage of B- during pregnancy is done. Then, are enumerated the experimental repercussion of B blockers and their more often theoretical than real undesirable effects, on the fetus. Sotalol is possibly a B-specially aggressive, when it is prescribed abusively, on account of its excellent diffusibility and of its high tissular impregnation.