Pulmonary barotrauma including orbital emphysema following inhalation of toxic gas

Inhalation lung injury induced by smoke bombs in children: CT manifestations, dynamic evolution features and quantitative analysis

Background

This retrospective study aimed to investigate the computed tomography (CT) manifestations, short-term dynamic evolution features and quantitative lung CT analysis of inhalation lung injury induced by smoke bomb flare.

Methods

Eleven pediatric patients (aged 11 to 13) who inhaled the smoke of smoke bombs underwent several low-dose chest CT scans. The image characteristics and their dynamic changes were observed and quantitative CT values were analyzed. The quantitative CT indicators included lung injury CT score (LICTS), lung fibrosis CT score (LFCTS), mean lung density (MLD), normally aerated volume ratio (NAVR) and reductively aerated volume ratio (RAVR). Box-plot was used to analyze the dynamic changes of each indicator and Spearman statistical method was used to analyze the correlation between any two indicators.

Results

(I) In most cases, there were multiple consolidation and massive ground-glass opacities (GGOs) in the two lungs, which aggravated in the early stage and then gradually dissoluted in the later stage. LICTS was positively correlated with MLD (r=0.811, P=0.000), while it was negatively correlated with NAVR (r=-0.712, P=0.000). There existed interstitial fibrosis in the later stage, and LFCTS was positively correlated with RAVR (r=0.382, P=0.028). (II) In one case, the patterns were like layered cake, i.e., consolidation with air bronchus signs in the accumulation area, GGOs in the aforementioned area and normal lung in the top area. The patterns aggravated in the early stage and quickly dissolved in the later stage, and only a few residual fibrotic lesions existed on the final scan. (III) For severe cases, pneumomediastinum and subcutaneous emphysema aggravated in the early stage and then gradually dissolved in the later stage.

Conclusions

The chest CT manifestations of inhalation lung injury induced by smoke bombs are predominantly GGOs and consolidation. They aggravate in the early stage and gradual dissolute in the later stage. CT quantitative values can contribute to evaluating the extent of this disease, and NAVR and RAVR can be used to assess pulmonary function.

Zinc Chloride (Smoke Bomb) Inhalation Lung Injury

STUDY OBJECTIVES

Zinc chloride smoke inhalation injury (ZCSII) is uncommon and has been rarely described in previous studies. We hypothesized that structural changes of the lung might correlate with pulmonary function. To answer this question, we correlated findings from high-resolution CT (HRCT) scan and the results of pulmonary function tests (PFTs) in patients with ZCSII.

DESIGN

Retrospective cohort study.

SETTING

University hospital.

PATIENTS

Twenty patients who had been hospitalized with ZCSII-related conditions.

MEASUREMENTS

The study included HRCT scan scores (0 to 100), static and dynamic lung volumes, and diffusing capacity of the lung for carbon monoxide (D(LCO)).

RESULTS

HRCT scans and PFTs were performed initially after injury (range, 3 to 21 days) in all patients and during the follow-up period (range, 27 to 66 days) in 10 patients. The predominant CT scan findings were patchy or diffuse ground-glass opacities with or without consolidation. The majority of patients showed a significant reduction of FVC, FEV1, total lung capacity, and D(LCO), but normal FEV1/FVC ratio values. Changes of functional parameters correlated well with HRCT scan scores. Substantial improvements in CT scan abnormalities and pulmonary function were observed at follow-up.

CONCLUSIONS

The majority of our patients with ZCSII presented with a predominant parenchymal injury of the lung that was consistent with a restrictive type of functional impairment and a reduction in Dlco rather than with obstructive disease. Our results suggest that HRCT scanning and pulmonary function testing may reliably predict the severity of ZCSII.

Orbital emphysema and diplopia following thoracotomy

PURPOSE

To describe the clinical and radiological findings in a patient with diplopia and orbital emphysema following thoracotomy.

METHODS

Reported is a 71-year-old woman who presented with diplopia several days following thoracotomy.

RESULTS

Physical examination revealed diffuse subcutaneous emphysema and a right hypertropia. Head computed tomography revealed facial and palpebral subcutaneous emphysema extending into the infratemporal fossa and orbits bilaterally. A chest tube was replaced and her diplopia resolved.

CONCLUSIONS

Subcutaneous emphysema can lead to diplopia and orbital emphysema in the absence of orbital trauma. Contrary to previously suggested mechanisms of orbital emphysema associated with subcutaneous emphysema, computed tomography imaging suggested that air entry into the orbit in this case was through the inferior orbital fissure.

Orbital emphysema: case reports and review of the literature

OBJECTIVE

This study was designed to describe the usual clinical findings of orbital emphysema as well as unusual and infrequent but important causes of this condition.

DESIGN

We present seven detailed cases of orbital emphysema and review the pertinent English-language literature published since 1900.

MATERIAL AND METHODS

Characterization of the seven patients with orbital emphysema illustrates the various causes and clinical findings of the disorder. Additionally, we review 78 previously published cases of orbital emphysema to determine the treatment and prognosis of this condition.

RESULTS

Trauma is the most frequent cause of orbital emphysema; however, orbital emphysema also may occur spontaneously or as a complication of pulmonary barotrauma, infection, and operation. In most cases, orbital emphysema resolves spontaneously without compromising ocular function. If excessive amounts of air accumulate within the orbit, however, complications such as occlusion of the central retinal artery or compressive optic neuropathy may lead to loss of vision if not recognized promptly and treated.

CONCLUSION

In most cases, orbital emphysema is an incidental, benign finding that resolves with time. Careful observation is the only treatment necessary unless an orbital fracture involves an infected sinus, in which case prophylactic orally administered antibiotics may be prescribed.