Diagnosis and conservative management of late tracheotomy complications in chronic ventilator-dependent patients

Myeloid Phenotypes in Tracheostomy-Associated Granulation Tissue

OBJECTIVE(S)

Tracheostomy-associated granulation tissue is a common, recurrent problem occurring secondary to chronic mucosal irritation. Although granulation tissue is composed of predominantly innate immune cells, the phenotype of monocytes and macrophages in tracheostomy-associated granulation tissue is unknown. This study aims to define the myeloid cell population in granulation tissue secondary to tracheostomy.

METHODS

Granulation tissue biopsies were obtained from 8 patients with tracheostomy secondary to laryngotracheal stenosis. Cell type analysis was performed by flow cytometry and gene expression was measured by quantitative real-time polymerase chain reaction. These methods and immunohistochemistry were used to define the monocyte/macrophage population in granulation tissue and were compared to tracheal autopsy control specimens.

RESULTS

Flow cytometry demonstrated macrophages (CD45+CD11b+) and monocytes (CD45+FSClow SSClow ) represent 23.2 ± 6% of the granulation tissue cell population. The M2 phenotype (CD206) is present in 77 ± 11% of the macrophage population and increased compared to the M1 phenotype (p = 0.012). Classical monocytes (CD45+CD14high CD16low ) were increased in granulation tissue compared to controls (61.2 ± 7% and 30 ± 8.5%, p = 0.038). Eighty-five percent of macrophages expressed pro-inflammatory S100A8/A9 and 36 ± 4% of macrophages co-localized CD169, associated with tissue-resident macrophages. M2 gene expression (Arg1/CD206) was increased in granulation tissue (3.7 ± 0.4, p = 0.035 and 3.5 ± 0.5, p = 0.047) whereas M1 gene expression (CD80/CD86) was similar to controls (p = 0.64, p = 0.3). Immunohistochemistry of granulation tissue demonstrated increased cells co-localizing CD11b and CD206.

CONCLUSIONS

M2 macrophages are the dominant macrophage phenotype in tracheostomy-associated granulation tissue. The role of this cell type in promoting ongoing inflammation warrants future investigation to identify potential treatments for granulation tissue secondary to tracheostomy.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:2346-2356, 2023.

37-Year-Old Tracheostomized Woman With Overdistended Tracheostomy Cuff and Difficulty Ventilating

CASE PRESENTATION

A 37-year-old woman with a medical history of myasthenia gravis resulting in progressive respiratory failure requiring continuous mechanical ventilation via tracheostomy, as well as multiple cardiac arrests leading to severe anoxic brain injury, was brought to the hospital from a nursing home because of difficulties with ventilation and oxygenation. On presentation to the ED, the patient was found to be agitated and tachypneic on a ventilator, generating low tidal volumes despite elevated peak airway pressures. Before the current presentation, the patient had been mechanically ventilated at a long-term acute care facility for the past 5 years. More recently, staff has noted intermittent loss of tidal volumes, temporarily responding to overinflation of tracheostomy cuff. Additionally, the tracheostomy tube was exchanged for an extra-long tracheostomy tube to improve tidal volumes; however, the problem persisted, prompting the current presentation.

Factors associated with the occurrence of stomal stenosis after tracheostomy in adults

OBJECTIVE

Although tracheal stomal stenosis can be life-threatening, factors associated with the occurrence of stomal stenosis remain unknown. This study was performed to evaluate these factors in adult patients.

METHODS

We retrospectively identified adult patients who underwent tracheostomy from 2010 to 2016 using a Japanese national inpatient and outpatient database. We performed Cox proportional hazard regression analyses to evaluate factors associated with the occurrence of tracheal stomal stenosis.

RESULTS

We obtained data on 25,436 eligible patients. The proportion of tracheal stomal stenosis was 0.9%. Tracheal stomal stenosis was significantly less likely to occur in patients with regular use of oral steroids [hazard ratio (HR), 0.28; 95% confidence interval (CI), 0.09-0.88; P = 0.03] and in male patients (HR, 0.75; 95% CI, 0.57-0.97; P = 0.03). The occurrence of tracheal stomal stenosis was significantly associated with use of a mechanical ventilator at home (HR, 2.54; 95% CI, 1.55-4.15; P < 0.001) and a body mass index of <18.5 kg/m² (HR, 1.45; 95% CI, 1.06-1.99; P = 0.02).

CONCLUSION

Our study revealed several factors that are associated with tracheal stomal stenosis. These findings may help physicians to manage tracheal stomas.

Long-Term Mechanical Ventilation: Recommendations of the Swiss Society of Pulmonology

Long-term mechanical ventilation is a well-established treatment for chronic hypercapnic respiratory failure (CHRF). It is aimed at improving CHRF-related symptoms, health-related quality of life, survival, and decreasing hospital admissions. In Switzerland, long-term mechanical ventilation has been increasingly used since the 1980s in hospital and home care settings. Over the years, its application has considerably expanded with accumulating evidence of beneficial effects in a broad range of conditions associated with CHRF. Most frequent indications for long-term mechanical ventilation are chronic obstructive pulmonary disease, obesity hypoventilation syndrome, neuromuscular and chest wall diseases. In the current consensus document, the Special Interest Group of the Swiss Society of Pulmonology reviews the most recent scientific literature on long-term mechanical ventilation and provides recommendations adapted to the particular setting of the Swiss healthcare system with a focus on the practice of non-invasive and invasive home ventilation in adults.

Endotracheal tube size to leakage ventilation and tracheal dilatation

PURPOSE

This study analyzed the clinical factors with the aim to determine the relationship between endotracheal tube (ETT) size and leakage ventilation (LV) and tracheal dilatation.

METHODS

All patients with ETT intubation and ventilator support for more than 6 months were retrospectively evaluated. The inner tracheal diameter (TD) was measured over image at the starting and 6 months after ventilator initiated. We compared the clinical factors, outcomes and complications between patients with and without LV, as well as with and without a TD enlarging more than 25% after 6 months (TDn). Logistic regression analyses of factors related to the LV and TDn were performed. The cut-off points of the ratio of outer diameter of ETT (OD) to TD were set and evaluated for their accuracy of predicting LV and TDn.

RESULTS

689 patients were enrolled initially and eventually 199 patients were included, of which 52 and 66 patients were identified to have LV and TDn, respectively. Patients with LV had a higher peak inspiratory pressure (PIP), smaller initial ETT OD/TD and higher incidence of pneumonia. Patients with TDn had a higher PIP, larger initial OD/TD and higher incidence of pneumonia. A higher PIP and smaller initial OD/TD were significantly related to LV and a higher PIP and larger initial OD/TD were significantly related to TDn. The incidence of LV and TDn was higher in patients with an initial OD/TD less than 0.51 and more than 0.54, respectively.

CONCLUSION

The initial ETT OD/TD ratio is a predictor for LV and TDn.