Chlorine inhalation injury with acute respiratory distress syndrome treated by extra-corporeal membrane oxygenation system

A 57-year old man who had been hitherto working in the electric industry for many years was presented in the emergency department of our institution. Throughout the same day, he had been working in a non-ventilated room without mask protection while pure chlorine leaked from a pipe occurred for 3 hours. He experienced headache, dyspnea, palpitations and chest tightness 4 hours later and was sent to our hospital with an oxygen mask, anxious consciousness, and obvious tachypnea.

https://www.peertechz.com/journals/global-journal-of-medical-and-clinical-case-reports Citation: Chen  physical examination. Consequently, he was intubated. A chest x-ray was ordered and it showed diffuse increased haziness over bilateral pulmonary parenchyma (Figure 1-A). Complete blood count and biochemistry profi les including liver function test, electrolytes, renal function test and coagulation profi le were within normal limits. Furthermore, the serum and urine toxicology ascertained no remarkable fi ndings. Arterial blood gas revealed a pH of 7.35, pCO 2 of 42.8 mmHg and pO 2

Discussion
Chlorine is one of the most pervasive toxic inhalants, although it was discovered in 1772. It is a yellow-green gas at room temperature with detectable odor. However, with prolonged exposure to chlorine, the ability to detect it tends to vanish. Chlorine is of widespread use in both households and industrial fi elds, and it has even been used as a weapon during previous wars [1]. Currently, human exposure to chlorine Most of the patients with acute chlorine exposure recovered without remarkable sequelae and only supportive therapy was deemed mandatory. The mean hospital stay length was less than 4 days. The long term sequelae had been described before and they include the development of occupational asthma (3), reactive airways dysfunction syndrome [4,5], and increased airway responsiveness [6].
The main destructive features of chlorine inhalation are direct mucosal injury and the release of free radicals which consequently give rise to an infl ammation process which produces Acute Lung Injury (ALI) or ARDS. Hypoxia is the hallmark of Cl 2 inhalation injuries [7]. The specifi c cause of hypoxia may be both V/Q mismatch and shunt formation [8].
According to the thoroughly reviewed literature regarding chlorine inhalation injury, ARDS is a rare presentation and mechanical ventilation is seldom used. The outcomes have been reported to be generally good with a low mortality rate, which was only 0.58% in cases of accidental chlorine exposure according to Evans' review [9]. On the other hand, should the patient develop ALI or ARDS, the administration of mechanical ventilation for a brief period of time, could be a life-saving measure. The cases that required mechanical ventilation are summarized in Table 1 [10][11][12][13][14][15][16]. Up to 39 cases that needed ventilation support after chlorine inhalation can be found in the reported cases. Among them, 15 cases had a mortal outcome, which yields a mortality rate of 38.5%. The majority of deaths occurred within the fi rst 3 days. The length of hospital stay ranged from 6 to 28.5 days and the complications included asthma and pneumothorax.
The ventilator settings for ARDS typically include: high PEEP, high frequency, permissive hypercapnia, and lower tidal volume ventilation [17]. The usage of intravenous corticosteroids and inhalation of beta-agonists had been widely discussed before for chlorine-related inhalation injury [14,18]. The goal of systemic corticosteroids administration in chlorine-related ARDS patients is to minimize the fi broproliferative phase of ARDS in lieu of the acute infl ammatory phase [19]. However, should a higher concentration of chlorine exposure occur along with its consequent ARDS and unstable hemodynamics, the course in the fi rst 72 hours would be miserable, in spite of thoughtful therapeutic management. According to a study with sheep, individuals with ARDS and shock will have stabilized vital signs 3 days after the chlorine exposure [20]. Therefore, it is important to focus on optimal management during this fi rst critical period time which is mainly the fi rst 72 hours after the insult. Under clinically feasibility, the veno-arterial

Conclusion
Chlorine inhalation injury accompanied with ARDS and necessity of ventilator support is a rarely seen clinical situation. A fatal outcome or concomitant refractory shock and hypoxemia under conventional therapeutic intervention are even rarer occurrences. In order to offer the patients a better chance to overcome the acute stage of chlorine inhalation injury, provided an ECMO system is clinically available, its application may be a life-saving and worthy intervention.

Consent
Written informed consent was obtained from the patient for publication of this Case report and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal.

Competing interests
In the past fi ve years we have never received reimbursements, fees, funding, or salary from an organization that may in any way gain or lose fi nancially from the publication of this manuscript, either now nor in the future. There are no nonfi nancial competing interests (political, personal, religious, ideological, academic, intellectual, commercial or any other) to declare in relation to this manuscript.

Authors' contributions
Te-Fu Chen carried out the patient primary care, medical records, reference collection and drafted the manuscript.
Chih-Hsien Wang and Gonzalez Lain Hermes conceived of the study, and participated in its design and coordination and helped to draft the manuscript. Wen-Je Ko are corresponded of this manuscript. All authors read and approved the fi nal manuscript.