Smoke inhalation injury is roughly defined as the injury of the bronchial tree and the respiratory system developing as a result of inhalation of particulate matter (soot) and chemical or thermal irritants found in smoke and accounts for up to 10,000 deaths every year in the United States [1]. Some of the most important compounds responsible for this type of injury are carbon monoxide (CO), hydrogen cyanide (HCN), free oxygen radicals (reactive oxygen species, or ROS), sulfur dioxide (SO2), benzene and other aromatic hydrocarbons, as well as ammonia (NH3) [2] [3] [4]. Despite their increasing concentrations in the industrial setting and markedly higher occupational exposure, inhalation of smoke during fires is the predominant mode of smoke related injury, as extensive nasopharyngeal irritation promotes breathing through the mouth and subsequent introduction of large amounts of smoke directly into the bronchial tree [1]. The clinical presentation depends on the amount of smoke inhaled, the concentration of gasses found in the smoke, and the ability of the individual's respiratory tract to cope with chemical and thermal injury [1] [2]. In most cases, mucosal edema and irritation eventually result in stridor, hoarseness, dyspnea, hypoxia, and tachypnea, whereas accompanying burns on the face and surrounding area is quite common [1] [3]. The presence of soot in the nasopharynx and sputum has also been documented as an important finding [3]. Loss of consciousness and respiratory insufficiency are signs of life-threatening smoke inhalation injury, in which case rapid therapeutic measures (mainly in the form of cessation of exposure to smoke) are mandatory [3] [4] [5].

• Hypoxemia

  Early hypoxemia is a contributor to over 50% of deaths. There are several clinical entities: upper airway obstruction, bronchospasm, consolidation, pulmonary edema, ARDS, and late pneumonia. [ncbi.nlm.nih.gov]

  The casts may completely occlude airways, including the upper airways, resulting in airway obstruction and hypoxemia. [clinicaladvisor.com]

  […] respiratory compliance if known Parameter Finding Value Rx.Torax no alveolar consolidation 0 alveolar consolidation de 1 quadrant 1 alveolar consolidation de 2 quadrant 2 alveolar consolidation de 3 quadrant 3 alveolar consolidation de 4 quadrant 4 Hypoxemia [clinicaltrials.gov]

  A physiological shunt causes profound hypoxemia and acute microvascular injury in severe cases. [dovepress.com]

  On ICU day 2, this patient developed moderate ARDS based on the onset, severity of hypoxemia, and radiographic result (Berlin definition for ARDS). [ispub.com]

• Congestive Heart Failure

  If positive, the pattern may be mixed, show an alveolar infiltrate, an interstitial infiltrate, or congestive heart failure. Infiltrates are more common in the upper lung fields. [ahcmedia.com]

• Cough

  […] with corrosives Soot on lips Burns of the mucosa Mucosal oedema Pharynx Inhalation of superheated smoke or steam Carbonised material in the pharynx Pharyngeal oedema Difficulty swallowing Larynx Inhalation of superheated smoke or steam Hoarse voice Cough [derangedphysiology.com]

  The most common symptom was cough, 46.7% and 73.3% in fire smoke and chronic cough group, respectively ( Table 2 ). [jtd.amegroups.com]

  However, patients who have a cough with wheezing (bronchospasm), indicating that the bronchial airways are narrowed or blocked, may be given a bronchodilator to relax the muscles and increase ventilation. [medical-dictionary.thefreedictionary.com]

  Cough : When the mucous membranes of the respiratory tract get irritated, they secrete more mucus. Bronchospasm and increased mucus lead to reflex coughing. [webmd.com]

  A cough When the mucous membranes of the respiratory tract get irritated, they secrete more mucus. Bronchospasm and increased mucus production lead to reflex coughing. [emedicinehealth.com]

• Hoarseness

  Clinical features of airway burns include soot in the airway, stridor, hoarseness, singed nose hair, and mucosal ulceration Historically, survivors of explosions and fires in enclosed spaces are more likely to have suffered airway burns Consequences of [derangedphysiology.com]

  No statistically significant correlation was found between intubation and any of the classic symptoms of smoke inhalation: stridor, hoarseness, drooling, and dysphagia (all p = 1.0). [ncbi.nlm.nih.gov]

  Call 911 if you experience the following symptoms with smoke inhalation: Hoarse voice Difficulty breathing Drawn out coughing spells Mental confusion Someone with smoke inhalation can get worse quickly. [webmd.com]

  If the patient has signs and symptoms of upper airway problems (hoarseness), they will most likely be intubated. The doctor places a tube down the throat to keep the airway from closing due to swelling. [emedicinehealth.com]

  In most cases, mucosal edema and irritation eventually result in stridor, hoarseness, dyspnea, hypoxia, and tachypnea, whereas accompanying burns on the face and surrounding area is quite common. [symptoma.com]

• Stridor

  Clinical features of airway burns include soot in the airway, stridor, hoarseness, singed nose hair, and mucosal ulceration Historically, survivors of explosions and fires in enclosed spaces are more likely to have suffered airway burns Consequences of [derangedphysiology.com]

  No statistically significant correlation was found between intubation and any of the classic symptoms of smoke inhalation: stridor, hoarseness, drooling, and dysphagia (all p = 1.0). [ncbi.nlm.nih.gov]

  Upper airway injury usually causes symptoms within minutes but occasionally over several hours; upper airway edema may cause stridor. [msdmanuals.com]

  In most cases, mucosal edema and irritation eventually result in stridor, hoarseness, dyspnea, hypoxia, and tachypnea, whereas accompanying burns on the face and surrounding area is quite common. [symptoma.com]

• Dyspnea

  In most cases, mucosal edema and irritation eventually result in stridor, hoarseness, dyspnea, hypoxia, and tachypnea, whereas accompanying burns on the face and surrounding area is quite common. [symptoma.com]

  Nonsoluble gases cause fewer immediate symptoms but can cause dyspnea or cough. Patients who develop ARDS have worsening dyspnea and increasing oxygen requirements. [merckmanuals.com]

  In some cases, there is a lower respiratory tract injury that results in wheezing, coughing, rhonchi, and dyspnea, among other symptoms. [pulgininorton.com]

  […] inhalation effects if exposed to fire in a confined space assess for airway injury and respiratory compromise — features of airway burns — upper airways: singed nasal airs, facial burns, soot in nose and pharynx, stridor, hoarseness — lower airways: wheeze, dyspnea [lifeinthefastlane.com]

• Tachypnea

  In most cases, mucosal edema and irritation eventually result in stridor, hoarseness, dyspnea, hypoxia, and tachypnea, whereas accompanying burns on the face and surrounding area is quite common. [symptoma.com]

  Clinical Manifestations of Hydrogen Cyanide Poisoning Early signs include anxiety, confusion, headache, hypertension, dyspnea, and tachypnea. Subsequently, coma, seizures, pupillary dilatation, hypotension, bradycardia, and arrhythmias occur. [clinicaladvisor.com]

  In small doses, headache, confusion, anxiety, dizziness, nausea, palpitations, tachycardia, tachypnea, and combativeness all may be found. [ahcmedia.com]

• Choking

  If the patient has respiratory distress or mental status changes, they may also be intubated to enable the staff to help with breathing, to suction mucus, and keep the patient from choking on secretions. [emedicinehealth.com]

  The survivors from fire accidents may inhale toxic combustion products generated by fires and present with symptoms that resemble asthma, such as severe cough, sputum, choking sensation, and wheezing ( 2 - 4 ). [jtd.amegroups.com]

• Gagging

  If the patient has an alteration of consciousness or loss of the gag reflex, intubation is indicated for airway protection and to provide 100% oxygen. A pediatric flexible fiberoptic bronchoscope requires a 4-mm tube orifice to pass. [ahcmedia.com]

• Chest Pain

  Primary endpoints were death, chest pain, and adverse changes in cardiopulmonary hemodynamics (arrhythmia, arterial blood pressure, electrocardiographic [ST segment] changes, and peak inspiratory pressure). [ncbi.nlm.nih.gov]

  But they often include Coughing and phlegm A scratchy throat Irritated sinuses Shortness of breath Chest pain or tightness Headaches Stinging eyes A runny nose If you have a chronic heart or lung problem, an inhalation injury can make it worse. [icdlist.com]

  Symptoms of CO are related to the amount of carboxyhemoglobin present in the blood as well as age and health of patient and can range from a slight headache or confusion to chest pain, stroke, or seizure, coma, & death. [cdemcurriculum.com]

• Cyanosis

  Note whether there is cyanosis. Note whether the chest wall moves normally and symmetrically. Assess the airway but, if there is any risk of cervical spine trauma, be careful with the neck. Note respiratory rate. Listen to the chest. [patient.info]

  (Table 2) Table 2 Clinical Manifestations of Carbon Monoxide Poisoning General Signs of Inhalational Injury Burns of the neck and face Singed nasal hair Soot-laden oral and nasal secretions Cough, hoarseness, dysphonia, and stridor Tachypnea, cyanosis [clinicaladvisor.com]

  The skin should be checked for cyanosis, cherry red color, or brownish tinge. The inhaled toxin may lead to necrosis, ulcers, or frank burns on exposed skin. Bullae formation on dependent parts is particularly common in carbon monoxide poisoning. [ahcmedia.com]

• Tachycardia

  Tachycardia, increased cardiac output, arrhythmias, and cardiac ischemia may also be evident. Retinal hemorrhages and cherry-red skin color, the “classic” manifestations of carbon monoxide poisoning, are relatively uncommon. [clinicaladvisor.com]

  […] icteric sclera, neck supple, no lymphadenopathy, no mass/carotid bruit, unable to assess oral cavity due to presence of endotracheal tube, dry and mild swollen lips Cardiovascular : S1/S2 with regular rate and rhythm, no murmurs/rubs/gallops, sinus tachycardia [ispub.com]

  In small doses, headache, confusion, anxiety, dizziness, nausea, palpitations, tachycardia, tachypnea, and combativeness all may be found. [ahcmedia.com]

• Facial Burn

  Intubation was positively correlated with physical examination findings of soot in the oral cavity (p < 0.001), facial burns (p = 0.025), and body burns (p = 0.025). [ncbi.nlm.nih.gov]

  "Upper airway sequelae in burn patients requiring endotracheal intubation or tracheostomy." Annals of surgery 201.3 (1985): 374. Bartlett, Robert H., et al. "Acute management of the upper airway in facial burns and smoke inhalation." [derangedphysiology.com]

  Furthermore, findings such as facial burns, soot in the nasopharynx and sputum, as well as voice changes are highly indicative signs of smoke inhalation injury, which is why the role of a proper physical exam must not be overlooked. [symptoma.com]

  — upper airways: singed nasal airs, facial burns, soot in nose and pharynx, stridor, hoarseness — lower airways: wheeze, dyspnea, APO, ARDS suspect significant systemic toxicity if severity of presentation is out of keeping with degree of burns (e.g. [lifeinthefastlane.com]

• Irritability

  Smoke inhalation injury refers to the chemical and thermal injury of the respiratory tract, as well as systemic toxicity, arising from inhalation of various irritants found in smoke. [symptoma.com]

  Smoke is heterogeneous and unique to each fire; it comprises particulates, respiratory irritants and systemic toxins as well as heat, all contributing to the pathological insult. [ncbi.nlm.nih.gov]

  It is more common for smoke to cause mild throat irritation, which is not a sign of a significant burn to the airway. [uhs.berkeley.edu]

• Confusion

  As many patients develop altered consciousness and confusion, a heterogeneous anamnesis (friends, relatives, or coworkers who were exposed together with the patient) can be of great help in identifying the circumstances that preceded the development of [symptoma.com]

  Smoke inhalation can cause a host of other injuries, including: Difficulty breathing Coughing Nose or throat irritation Nausea Headaches Fainting Confusion Seizures Coma Corneal and other eye damage If negligence played any kind of role in a fire, the [winstonbriggslaw.com]

  Symptoms of carbon monoxide poisoning include headache, nausea, drowsiness, confusion, and coma. Damage to the windpipe, breathing passages, or lungs can cause cough, wheezing and/or shortness of breath. [msdmanuals.com]

  Symptoms of smoke inhalation include Local irritant phenomena: Cough, wheezing, stridor Hypoxic manifestations: Confusion, lethargy, coma Carboxyhemoglobin (COHb) levels Bronchoscopy Chest x-ray Smoke inhalation is suspected in patients with respiratory [merckmanuals.com]

• Altered Mental Status

  Pulmonary injury should be considered in any patient with history of burn in a closed space, loss of consciousness, or altered mental status. [totalburncare.com]

  Carboxyhemoglobin and methemoglobin levels : This level should be obtained in all smoke inhalation victims with respiratory distress, altered mental status, low blood pressure, seizures, fainting, and blood pH changes. [webmd.com]

  Carboxyhemoglobin and methemoglobin levels: These levels should be measured in all smoke inhalation victims with respiratory distress, altered mental status, low blood pressure, seizures, fainting, and blood pH changes. [emedicinehealth.com]

  mental status to hypotension, arrhythmia, and cardiovascular collapse followed by shock. [emedicine.medscape.com]

  Ethanol levels should be determined, particularly if the patient has any altered mental status. Likewise, toxicology screens may be appropriate for some patients. Cyanide levels often are unavailable or greatly delayed. [ahcmedia.com]

• Dizziness

  Common side effects of carbon monoxide poisoning include: Dizziness Headaches Nausea Vomiting Carbon Monoxide is especially dangerous because it can not be smelled (odorless) or seen (colorless). [skylawgroup.com]

  Changes in mental status: The presence of chemicals and low levels of oxygen can cause symptoms such as dizziness, confusion, seizures or even lack of consciousness and fainting. [work4youlaw.com]

  In small doses, headache, confusion, anxiety, dizziness, nausea, palpitations, tachycardia, tachypnea, and combativeness all may be found. [ahcmedia.com]

  […] respiratory distress Nausea and vomiting Neurologic findings, including loss of consciousness Carboxyhemoglobin >10% within the first hour Clinical Manifestations of Carbon Monoxide Poisoning With mild exposure, neurologic symptoms include headache, dizziness [clinicaladvisor.com]

• Agitation

  In addition, if the patient is intubated, the presence of an endotracheal tube, invasive monitor devices, suctioning, and mechanical ventilation further increases a patient’s discomfort and increases agitation. [ispub.com]

  […] changes, hoarseness, stridor (these are particularly worrying symptoms), cough, burns to the face, lips, tongue, mouth, pharynx, or nasal mucosa, soot in the sputum, nose, and mouth, respiratory distress, decreased level of consciousness or confusion, agitation [academic.oup.com]

The need for rapid treatment necessitates a prompt clinical workup by the physician, but in order to gain sufficient evidence for a presumptive diagnosis, a detailed patient history, and a thorough physical examination must be performed. As many patients develop altered consciousness and confusion, a heterogeneous anamnesis (friends, relatives, or coworkers who were exposed together with the patient) can be of great help in identifying the circumstances that preceded the development of symptoms [4]. Furthermore, findings such as facial burns, soot in the nasopharynx and sputum, as well as voice changes are highly indicative signs of smoke inhalation injury, which is why the role of a proper physical exam must not be overlooked [1]. As soon as clinical suspicion is raised, both laboratory and imaging studies should be performed [3] [6]. A complete blood count (CBC), pulse oximetry, and arterial blood gas (ABG) analysis are vital for evaluating the status of tissue perfusion and oxygen content, whereas computed tomography (CT) of the thorax is the recommended imaging modality [1] [3] [4] [5]. Pulmonary function testing (spirometry), electrocardiography (ECG), and measurements of carboxyhemoglobin are also a part of the initial workup, but in order to make a definite diagnosis and establish the severity of smoke inhalation injury, fiberoptic bronchoscopy (FOP), although being an invasive procedure, is the gold standard [2] [6].

• Atelectasis

  Although he survived the acute stages following injury, his pulmonary function subsequently deteriorated with a damaged trachea and bronchi, repeated attacks of pneumonia, atelectasis, pneumothorax and lung fibrosis, leading to death with hypercapnia [ncbi.nlm.nih.gov]

  Subglottic stenosis, bronchiectasis, pulmonary oedema and atelectasis can occur. [patient.info]

  Chronic bronchitis, bronchiolitis obliterans, bronchial stenosis, lung fibrosis, bronchiectasis and atelectasis have been reported to be resulted from exposure to fire smoke and subsequent inflammatory consequences ( 16 ). [jtd.amegroups.com]

  Results in: increased airway resistance post-obstructive atelectasis and emphysema 24-48 h after injury microvascular permeability is increased with resultant low pressure pulmonary oedema Clinical features Following should raise suspicion of inhalation [aic.cuhk.edu.hk]

  There is limited evidence in victims of smoke inhalation that these techniques limit atelectasis and barotrauma, 16–18 but it is a common sense strategy to avoid ventilator-induced lung injury in these at-risk patients A regimen of aerosolized heparin [academic.oup.com]

• Pulmonary Infiltrate

  On ICU day 5, she was weaned from vasopressor support, her chest x-ray showed decreasing bilateral pulmonary infiltrates, and she had a decreased FiO2 requirement with increasing PaO2/FiO2 ratio of 210. [ispub.com]

  Although some authors reported that bronchial wall thickening was sometimes found on initial chest radiographs, patients with inhalation injuries often have a normal chest radiograph at initial stages. 38 In contrast, the presence of pulmonary infiltrates [dovepress.com]

• Bilateral Pulmonary Infiltrates

  On ICU day 5, she was weaned from vasopressor support, her chest x-ray showed decreasing bilateral pulmonary infiltrates, and she had a decreased FiO2 requirement with increasing PaO2/FiO2 ratio of 210. [ispub.com]

• Hypercapnia

  Severe hypercapnia tended to be more frequent during HFOV among patients with smoke inhalation. [ncbi.nlm.nih.gov]

  Permissive hypercapnia can be used if the targeted pH is above 7.25. [dovepress.com]

  Patients must be closely monitored and early intubation should be considered if the patient demonstrates hypoxia/hypercapnia or carbon monoxide/cyanide toxicity [3]. [nuemblog.com]

  Burns 2007 ; 33 : 2 – 13 17 Permissive hypercapnia as a ventilatory strategy in burned children: effect on barotrauma, pneumonia, and mortality. [academic.oup.com]

• Base Deficit

  Avoid large fluid volumes aiming to either correct any base deficit or target urine output in excess of 0.5 ml kg −1 h −1. [academic.oup.com]

This case review details the treatment of a 32-year-old woman who was at 36 weeks of gestation on admission to the Evans-Haynes Burn Center. The authors will report her injuries and the course of treatment. [ncbi.nlm.nih.gov]

Moreover, no worldwide consensus criteria exist for its diagnosis, severity grading, and prognosis. Therapeutic approaches are highly variable depending on the country and burn centre or hospital. [ncbi.nlm.nih.gov]

Prognosis Although the outcome depends of the severity of the smoke inhalation and the severity of any accompanying burns or other injuries, with prompt medical treatment, the prognosis for recovery is good. [medical-dictionary.thefreedictionary.com]

Due to its relative rarity, information on prognosis is not abundant. [patient.info]

Predicting prognosis in thermal burns with associated inhalational injury: a systematic review of prognostic factors in adult burn victims. J Burn Care Res 2010;31:529-539. [ Links ] 28. Mackie DP, van Dehn F, Knape P, et al. [scielo.org.co]

Carbon monoxide and cyanide toxicity: etiology, pathophysiology and treatment in inhalation injury. Expert Rev Respir Med 2013;7:159-170. [ Links ] 21. Burillo-Putze G, Nogué-Xarau S, Pérez-Castrillón JL, Dueñas-Laita A. [scielo.org.co]

Etiology and consequences of respiratory failure in thermally injured patients. Am J Surg 1993;166:592-597. 20. Peters WJ. Inhalation injury caused by the products of combustion. Can Med Assoc J 1981;125:249. 21. Rue LW, Cioffi WG, Mason AD, et al. [ahcmedia.com]

We aimed to investigate the epidemiology and outcomes of this select patient population. [ncbi.nlm.nih.gov]

الصفحة 441 - Becklake MR: Asbestos-related diseases of the lung and other organs: Their epidemiology and implications for clinical practice. ‏ الصفحة 279 - Intravascular activation of complement and acute lung injury. [books.google.com]

Epidemiology of burn injuries globally. UpToDate. [Cited 10 Apr 17]. Available at: https://www.uptodate.com/contents/epidemiology-of-burn-injuries-globally. [ Links ] 2. World Health Organization. Burns. 2016; [Cited 17 Apr 17]. [scielo.org.co]

In contrast, Akgun & Gorguner (2010) report that acute lung injury due to inhalation of flaming gas seems to be epidemiologically more common among miners, because of the combination of inescapable confinement and limited fresh gas supply. [derangedphysiology.com]

Epidemiology Most burns managed in hospitals are from scalds (54%) and contact burns (23%). [academic.oup.com]

Treatment strategies should be planned based on these pathophysiological aspects. [ncbi.nlm.nih.gov]

How can smoke inhalation be prevented? To prevent fires, make sure that electrical wiring, chimneys, wood stoves, and space heaters are working properly. Use flammable liquids safely and store them in a locked area out of the reach of children. [uhs.berkeley.edu]

Primary prevention is the most important way to reduce the poor outcome from significant exposure. [ncbi.nlm.nih.gov]

All were back to work, except for two who continued to need artificial airways. [ 27 ] Prevention The prevention of smoke injury is largely the prevention of fire but, if it does occur, then early warning is necessary. Smoke detectors save lives. [patient.info]

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