Modeling thermal burns due to airbag deployment

Prompt Management of Airbag Burn Injuries Leads to Optimized Patient Outcomes: A Pilot Study

BACKGROUND

Dual airbags are required to be installed and available for use in all motor vehicles since 1997. The National Highway Traffic Safety Administration reported that 50,457 lives were saved by airbags from 1987 to 2017; however, airbag deployment can cause injuries, including thermal and chemical burns, hyperpigmentation, and dysaesthesia. There is little information available in the literature regarding differences in outcomes between promptly visiting a plastic surgeon and waiting for treatment, especially as an injury may not be immediately apparent or patients may not know that airbag burn injuries may be delayed in presenting.

METHODS

This is a retrospective cohort pilot study conducted among 14 patients who presented to a plastic surgeon between January 1, 2019 and June 30, 2022 owing to injuries from airbag deployment. An early visit was considered ≤30 days, and a late visit was >30 days. Other variables collected included age, sex, Fitzpatrick skin type, smoking status, comorbidities, type of injury, injury site, pain status, hyper/hypopigmentation, dysaesthesia, epithelialization, and improvements in pain, pigmentation, and dysaesthesia from treatment.

RESULTS

The mean age was 36.0 years (standard deviation (SD) 17.9). The majority were female (85.7%), non-smokers (87.5%), and not diabetic (75.0%). Only six patients (42.9%) visited their doctor within one month of injury. Most patients experienced dysaesthesia (85.7%) and pain (71.4%). Thirteen of the 14 patients had hyperpigmentation or hyperemia, and one had hypopigmentation. Full or slight epithelialization was seen in 35.7%, and nine of the 14 patients had no epithelialization. Ongoing issues were a factor for 64.3% of these patients; 42.9% had ongoing issues with hyperpigmentation. A full recovery was seen in 28.6% of the patients. The patients who saw the plastic surgeon by day 30 or less (early) from the time of injury had a 66.7% improvement in pigmentation and 33.3% resolution in pain. Of those who went to the surgeon beyond 30 days (late), 25% had improvement in pigmentation and 37.5% had resolution of pain. Improvement in dysaesthesia occurred in both groups, but those who saw the plastic surgeon early had 33.3% resolution, while 37.5% of those who went late improved. Of those who went late to the surgeon, only 12.5% had epithelialization, while 66.7% of those who went within 30 days showed signs of (full or slight) epithelialization.

CONCLUSION

Patients involved in motor vehicle collisions (MVCs) should be informed of the delayed fashion in which airbag burns can develop. An ostensibly mild burn may portend long-term consequences, especially if such injuries are not addressed in a prompt manner. Our study demonstrates how airbag burn injuries and their sequelae are best addressed with early care.

A case report on air bag induced skin burn in a road traffic injury: An experience

INTRODUCTION

Air bag deployment after high velocity trauma has been associated with burn injuries. So, we aimed to present a clinical case report associated with air bag deployment experienced by the author himself.

CASE PRESENTATION

The author was driving a hatchback car which collided head on with the high speeding vehicle from opposite direction. He sustained a burn injury around 4 × 3 cm in size in the flexor aspect of right forearm involving epidermis and some part of dermis which was superficial partial thickness in nature when the air bag deployment was observed at both the sides. Burn injury was healed with topical antibiotics and regular dressings with no any complications.

DISCUSSION

Air bag deployment has always been a safety measures for the road traffic injuries but the safety comes with a cost. It has been associated with burn injuries, especially chemical induced, thermal and frictional burns. Timely diagnosis of type of burn and intervention is required in order to minimize complications associated with burns.

CONCLUSION

Though burn injuries associated with air bag deployment cause less harm or complications, the companies making such commodities should explore the further options in order to develop burn injury free vehicle safety.

Paediatric Burns From Deployment of a Concealed Aviation Seatbelt Airbag

The advantages of airbags in reducing the rate of severe injuries and fatalities in motor vehicle crashes are well known but the physical act of airbag deployment can lead to injury to the passenger and the spectrum of airbag trauma resulting from deployment of vehicle airbags has been extensively reported. We present the first reported case of a pediatric burn injury resulting from the accidental deployment of an airbag in an aircraft. A four-year-old female child sustained injuries to the left side of her face and body while she was aboard a stationary airplane and the airbag concealed within the seat belt of her airplane seat unexpectedly and inexplicably deployed just before departure. We are presenting the case to increase awareness of the possibility of this injury in aircraft and to enable minimization of such accidents as well as help establish protocols for dealing with such mishaps if there were to happen.

A Systematic Review on Airbag-Induced Burns

Airbags significantly reduce fatalities and injuries in automobile crashes, but they have been found to be associated with burns. Specifically, airbags can cause burns through thermal or chemical mechanisms and commonly affect the arms, hands, face, and eyes. While most airbag-induced burns are minor, some may cause unfavorable outcomes. Our study aimed to systematically review airbag-induced burns to assess etiology, type, and treatment of these injuries. A systematic review of case reports pertaining to airbag-induced cutaneous and ocular burns was conducted. Data reviewed included type/location of burns, severity of burn, total number of patients, treatment, complications, and outcome after treatment. We identified 21 case reports that met our inclusion criteria with a total of 24 patients reported in the studies. Of the studies identified, 38% were chemical burns and 25% were thermal burns. Most commonly the upper extremities were burned in 42% of cases, followed by eyes (25%) and face (21%). Most burns identified were superficial partial thickness (58%). Treatment outcomes were good for cutaneous burns, with 95% healing without complication. However, ocular injuries lead to permanent impaired eye function in 71% of cases. In our systematic review, we highlighted the common risk factors, prognosis, and treatment for thermal, chemical, and ocular burns. Airbag-induced burns have a relatively good prognosis but must be recognized and treated immediately to reduce the risk of serious sequelae.

Airbag Burns: An Unfortunate Consequence of Motor Vehicle Safety

Thousands of people are injured in motor vehicle collisions daily and the mandated installation of airbags protects passengers but can also cause injuries from deployment including cutaneous burns. We sought to characterize the patterns and outcomes of burns resulting from airbag deployment by performing a retrospective review of all patients evaluated by the burn service from May 1, 2015 to April 30, 2019. Inclusion criteria were patients of all ages with burn injuries related to airbag deployment. Demographic data, burn characteristics, and outcomes were reviewed. Seventeen patients met the inclusion criteria: 82.4% female and 17.6% male. The average age was 40.4 years. Fifteen patients had second-degree and two had third-degree burns. The average TBSA was 0.45%. The hands or upper extremity (88%) were most often injured, but there were two chest, one neck, and one anterior thigh burns. Eight patients suffered multiple burns. Burn etiology (chemical vs thermal) was often not specified. No patients required hospitalization or surgical intervention, and all wounds healed with wound care. The average time to re-epithelialization was 11 days. Although airbags prevent mortality and serious injury, the exothermic chemical reaction that inflates the airbag is responsible for deployment-related burns. Since there is a chemical and thermal component, all airbag-related burns should undergo chemical decontamination on the initial presentation. Burns related to airbag deployment tend to be small and do not require grafting; however, patients suffer from associated pain, scarring, and burn management can be a financial and time burden to the patient.

Injuries, death and vehicle airbag deployment

Airbags are impact-activated safety devices which deploy from the interior of vehicles to protect occupants from trauma during crashes. Although airbags effectively reduce the risk of death and injury, this it is not without issues. For example, high-impact unbelted rigid-barrier testing in the USA led to the adoption of powerful, large airbags that were associated with numerous airbag-related deaths and injuries. In contrast, European designs were tested and certified in conjunction with the use of three-point restraint systems, meaning that the airbags could be smaller with reduced ‘punch-out’ power. An overview is provided of the mechanism of action of airbags and the associated non-lethal and lethal injuries that may be sustained by vehicle occupants.

Airbag deployment: Infrared thermography and evaluation of thermal damage

The performance of airbag and its deployment are based on a fast exothermic-chemical reaction. The hot gas resulting from the chemical reaction which results in airbag deployment can cause thermal damage and skin burning for the car passenger. The thermal burns due to airbags are of two types: burns due to direct contact with the airbag surface and burns resulting from exposure to the hot gas leaving the deflation vents of the airbag. In this research, for experimental study of the burns resulting from exposure of the skin to airbag, using infrared thermography, the extent of temperature rise of the airbag surface was detected and measured from the zero moment of its inflation. Next, using Henriques equation, the extent of thermal damage caused by airbag deployment and its resulting burn degree was calculated. The results indicated that during the inflation of airbag, the maximum temperature of its surface can be 92 °C ± 2 °C. Furthermore, if the vehicle's safety system functions within the predicted time intervals, the risk of thermal damage is virtually zero. However, if even a slight delay occurs in detachment of the passenger's head and face off the airbag, second- and third-degree burns could develop.

Systems biology and inflammation

Inflammation is a complex, multiscale biological response to threats - both internal and external - to the body, which is also required for proper healing of injured tissue. In turn, damaged or dysfunctional tissue stimulates further inflammation. Despite continued advances in characterizing the cellular and molecular processes involved in the interactions between inflammation and tissue damage, there exists a significant gap between the knowledge of mechanistic pathophysiology and the development of effective therapies for various inflammatory conditions. We have suggested the concept of translational systems biology, defined as a focused application of computational modeling and engineering principles to pathophysiology primarily in order to revise clinical practice. This chapter reviews the existing, translational applications of computational simulations and related approaches as applied to inflammation.

Translational systems biology of inflammation

Inflammation is a complex, multi-scale biologic response to stress that is also required for repair and regeneration after injury. Despite the repository of detailed data about the cellular and molecular processes involved in inflammation, including some understanding of its pathophysiology, little progress has been made in treating the severe inflammatory syndrome of sepsis. To address the gap between basic science knowledge and therapy for sepsis, a community of biologists and physicians is using systems biology approaches in hopes of yielding basic insights into the biology of inflammation. “Systems biology” is a discipline that combines experimental discovery with mathematical modeling to aid in the understanding of the dynamic global organization and function of a biologic system (cell to organ to organism). We propose the term translational systems biology for the application of similar tools and engineering principles to biologic systems with the primary goal of optimizing clinical practice. We describe the efforts to use translational systems biology to develop an integrated framework to gain insight into the problem of acute inflammation. Progress in understanding inflammation using translational systems biology tools highlights the promise of this multidisciplinary field. Future advances in understanding complex medical problems are highly dependent on methodological advances and integration of the computational systems biology community with biologists and clinicians.

Translational systems biology: introduction of an engineering approach to the pathophysiology of the burn patient

The pathophysiology of the burn patient manifests the full spectrum of the complexity of the inflammatory response. In the acute phase, inflammation may have negative effects via capillary leak, the propagation of inhalation injury, and development of multiple organ failure. Attempts to mediate these processes remain a central subject of burn care research. Conversely, inflammation is a necessary prologue and component in the later stage processes of wound healing. Despite the volume of information concerning the cellular and molecular processes involved in inflammation, there exists a significant gap between the knowledge of mechanistic pathophysiology and the development of effective clinical therapeutic regimens. Translational systems biology (TSB) is the application of dynamic mathematical modeling and certain engineering principles to biological systems to integrate mechanism with phenomenon and, importantly, to revise clinical practice. This study will review the existing applications of TSB in the areas of inflammation and wound healing, relate them to specific areas of interest to the burn community, and present an integrated framework that links TSB with traditional burn research.