What is the Morbidity Rate for Smoke Inhalation?

Patient Presentation
An 18-month-old male came to clinic with cough for ~ 3 days that occurred throughout the day and night.
It was more pronounced when he was actively playing. He also had runny nose but no fever. The family had tried his albuterol inhaler without much change in the cough. The past medical history was postive for acute intermittent bronchospasm/asthma that had required 2 courses of steroids but no emergency room or hospital admissions.
The social history revealed that the families duplex home had been destroyed by fire 4 days previously. The child had been in the home but all family members and the residents of the other part of the duplex had gotten out. The father had been treated for smoke inhalation at the emergency room and released. The family had been living in temporary housing since the fire. There were sick contacts at the child’s daycare with viral illnesses.

The pertinent physical exam showed a well-appearing male with normal vital signs and growth. His oxygen saturation was 99% on room air. He had clear rhinorrhea and normal tympanic membranes. His lungs had coarse breath sounds but no wheezing or rales. The rest of his examination was negative.

The diagnosis ofan upper respiratory tract infection was made. The pediatrician recommended symptomatic relief. The mother said that she was concerned because of the asthma and the smoke because “He was around all the smoke while the fire was burning. We just stayed there and watched. I didn’t think that it could make him sick,” she said. The pediatrician noted that the child was well around the time of the fire, and now looked like he had only the viral syndrome. “Mild smoke inhalation is usually treated in the emergency room with oxygen just like his father, so I don’t think that is the problem. It is possible that he was around some chemicals or particles in the smoke, but at this point there really isn’t anything that I can do. I think this is just a virus, but if he gets sicker, please call us or bring him back.” He also had the clinic social worker talk with the family to try to identify other needs they might have because of the fire.

Discussion
A recent systematic review of house fires in high-income countries found that the risk factors for unintentional house fire incidents included: more children under 5 years of age, more people in the home, more males in the home, adults who are not working, low-income, household smokers, non-privately owned housing, poor condition housing. Other risk factors are not having smoke detectors, but more importantly not having a working smoke detector.

Risk factors for injuries or fatalities is similar to the the risk factors for incidents but also includes people who are vulnerable such as a disabled resident, someone living alone, or someone impaired by drugs/alcohol. Nights, weekends and winter time also increase the risk of injuries/fatalities. Fire related deaths in children were up to 38 times higher in a a household where the adults are non-working or with long-term unemployement. Households with children between 5 and 17 years, or residents 65+ years have a decreased risk fo fire fatality.

Learning Point
“Inhalation injury is present in approximately 30% of all cutaneous burning patients. Localized pulmonary damage occurs as a result of both thermal injury and chemical irritation from contents of combustion.” Airway edema and potential airway obstruction are the concerns above the larynx due to thermal injury. Chemical burns occur below the larynx due to incomplete products of combustion including carbon monoxide and hydrochloric acid. With inhalation injury surfactant is inactivated leading to microatelectesis, and perfusion ventilation mismatch. Pulmonary shunting leads to pulmonary edema and microvascular injury. Severe inhalation injury can also trigger systemic inflammatory response. “Resulting pulmonary dysfunction last four months even after patients appear to have recovered from initial insult.” “The presence of inhalation injury and it’s associated pulmonary complications increases cutaneous burn mortality and morbidity rates from 3-10% to 20-30%.” Pediatric patients with smoke inhalation injury are less common than in adults but those with inhalation injuries usually have increased total burn surface areas which also indicates more significant injury.

Questions for Further Discussion
1. What are indications for admission because of a burn? A review can be found here
2. What should families do for fire safety? A review can be found here
3. What types of chemicals can be given off in a house fire?
4. What resources are available in your community for families after a house fire?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for these topics: Inhalation Injuries and Burns.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Wood RL, Teach SJ, Rucker A, Lall A, Chamberlain JM, Ryan LM. Home Fire Safety Practices and Smoke Detector Program Awareness in an Urban Pediatric Emergency Department Population. Pediatr Emerg Care. 2016 Nov;32(11):763-767.

Tan A, Smailes S, Friebel T, Magdum A, Frew Q, El-Muttardi N, Dziewulski P. Smoke inhalation increases intensive care requirements and morbidity in paediatric burns. Burns. 2016 Aug;42(5):1111-1115.

Turner SL, Johnson RD, Weightman AL, Rodgers SE, Arthur G, Bailey R, Lyons RA. Risk factors associated with unintentional house fire incidents, injuries and deaths in high-income countries: a systematic review. Inj Prev. 2017 Apr;23(2):131-137.

Author
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa