Six month follow-up of fourteen victims with short-term exposure to chlorine gas

Chlorine and its impact on an emergency department

INTRODUCTION

An incident involving the release of chlorine gas from the pump room at a local swimming pool resulted in 54 patients seeking treatment in the emergency departments (EDs) of two local, tertiary-level hospitals in Singapore. The hospital hazardous materials (HAZMAT) disaster plan was activated. This report describes how one of the EDs organized in response to the disaster.

EVENT

Of the 54 people seeking treatment, 36 were treated in the ED at the Singapore General Hospital. The patients were decontaminated at shower facilities prior to entering the ED. The ED was reorganized to cope with existing patients, as well as the large influx of patients from the event site. A protocol was established in coordination with the local drug and poison information center to manage the patients who suffered from chlorine inhalation. Most patients were observed in the ED and subsequently discharged. Outpatient review appointments were scheduled.

INJURIES

Acute respiratory symptoms were the most common symptoms., Four children and four adults were admitted to the hospital, and the other patients were discharged from the ED after observation. All of the chest x-rays were normal on the day of the chlorine inhalation. There were no mortalities or significant morbidities, even up to six months after the incident.

CONCLUSIONS

Although this chlorine HAZMAT incident did not cause severe injuries, and only a limited number of persons required admission to the hospital, some valuable lessons were learned.

Longitudinal monitoring of lung injury in children after acute chlorine exposure in a swimming pool

RATIONALE

Acute exposure to chlorine gas results in respiratory impairment, but few data are available on the pathobiology of the underlying lung damage.

OBJECTIVES

To assess lung function and potential lung damage pathways in the acute phase and longitudinally over a 15-mo follow-up after acute chlorine exposure.

METHODS

Ten previously healthy children were accidentally exposed to chlorine gas at a swimming pool because of an erroneous servicing procedure. The fraction of nitric oxide in exhaled air (Fe(NO)), exhaled breath condensate compounds, and serum Clara cell-specific protein CC16 were repeatedly measured.

MAIN RESULTS

In the acute phase, all patients had respiratory distress (one child required mechanical ventilation) and reduced lung function (median and interquartile range: FVC, 51 [43-60]% predicted; FEV(1), 51 [46-60]% predicted). This was accompanied by low Fe(NO) (4.7 [3.9-7.9] ppb), high exhaled breath condensate leukotriene B(4) (LTB(4)) levels (24.4 [22.5-24.9] pg/ml), and increased serum CC16 levels (mean +/- SEM, 23.4 +/- 2.5 microg/L). Lung function returned to normal in 15 d (FVC, 97% predicted [82-108], and FEV(1), 92% predicted [77-102]). Fe(NO) reached normal values after 2 mo (12.6 [11.4-15] ppb), whereas LTB(4) levels were still increased (12 [9.3-17.1] pg/ml).

CONCLUSION

Children acutely exposed to chlorine in a swimming pool presented a substantial lung function impairment associated with biochemical exhaled breath alterations, represented mainly by an increase in LTB(4) and a reduction in Fe(NO). Although lung function and Fe(NO) improved within a few weeks, the increased levels of exhaled LTB(4) persisted for several months.

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.

Short term respiratory effects of acute exposure to chlorine due to a swimming pool accident

OBJECTIVE

Acute exposure to chlorine causes lung damage, and recovery may proceed slowly for several weeks. The short term respiratory effects of acute chlorine inhalation during a swimming pool accident were examined.

METHODS

A total of 282 subjects (134 children, aged <14 years) inhaled hydrogen chloride and sodium hypochlorite during an accident caused by a malfunction of the water chlorinating system in a community pool in Rome in 1998. Most people received bronchodilators and cortisone at the emergency room; five children were admitted to hospital. A total of 260 subjects (92.2%) were interviewed about duration of exposure (<3, 3--5, >5 minutes), intensity of exposure (not at all or a little, a moderate amount, a lot), and respiratory symptoms. Lung function was measured in 184 people (82 children) after 15--30 days. The effects of exposure to chlorine were analysed through multiple linear regression, separately in adults and in children.

RESULTS

Acute respiratory symptoms occurred among 66.7% of adults and 71.6% of children. The incidences were highest among those who had chronic respiratory disease and had a longer duration of exposure. In about 30% of the subjects, respiratory symptoms persisted for 15--30 days after the accident. Lung function levels were lower in those who reported a high intensity of exposure than in those who reported low exposure, both in children and in adults (mean (95% confidence interval (95% CI)) differences in forced expiratory volume in 1 second (FEV(1,)) were -109 (-310 to 93) ml, and -275 (-510 to -40) ml, respectively).

CONCLUSION

Persistent symptoms and lung function impairment were found up to 1 month after the incident. Although community pool accidents happen rarely, the medical community needs to be alerted to the possible clinical and physiological sequelae, especially among susceptible people.

Chlorine inhalation: the big picture

BACKGROUND

Causes of acute chlorine exposures from community pool accidents have many reported etiologies. This case series involves 13 children exposed to high levels of chlorine at two community pools after an unusual mishap in the chlorination maintenance procedure.

CASE REPORT

During maintenance, the water feeding lines to pools are normally turned off, the chemicals replaced, the water turned back on, and the chemicals then reinjected into the line. In two separate disasters in the summer of 1996, the feeding lines were not reprimed with water before the reactants, sodium hypochlorite and muriatic acid, were injected. This caused an unusually high volume of concentrated chlorinated water to be released when refed to the pool.

RESULTS

All patients were treated with beta agonists and humidified oxygen, and five were admitted. None received bicarbonate inhalation. An extensive literature review of chlorine inhalation injuries indicates considerable variance in opinions of the pathophysiology, clinical presentation and treatment modalities, especially steroids and bicarbonate inhalation.

CONCLUSION

In community pools, failure to reprime feeding lines with water after replacing and injecting chlorinating reactants may result in severe and large-scale chlorine exposures. Beta agonist administration and humidified oxygen remains the mainstay of treatment; steroid therapy and bicarbonate inhalation are still inadequately supported.

Inhalation of chlorine gas

The clinical features of acute chlorine gas inhalation, and its management are reviewed. Current medical views on the chronic effects of an acute overwhelming exposure on lung function (reactive airways dysfunction syndrome), and the more controversial field of lung disease secondary to repeated inhalations of lower concentrations of chlorine gas are discussed.