Burns

1.0 CHAPTER ONE

INTRODUCTION

B urns are injuries sustained from contact with heat energies, chemical agents or their combined effect and are classified as chemical, electrical, fire or radiation. External and internal structures can be affected depending on the intensity and duration of exposure since a burn wound remain a function of the heat load, the duration of contact and the conductibility of the affected tissue. Inhaled smoke causes respiratory distress that may be life threatening.

Burns occur mainly due to negligence, carelessness, civilization, family indulgence and other risky practices that are avoidable with destruction of houses, markets, offices, institutions, oil installations and farmlands. Survival possibility for badly burned victims is doubtful but those that escape death live with scars, disfigurement or disability.

Burn incidences are more frequent during summer or harmatan season due to the dry nature of the atmosphere and the environment. The elderly and the very young are mostly at risk while factory workers face challenges from flammable, hazardous and electrical materials.

Management of burn victims is always an intensive practice by a team of the medical profession with specialized training. The objective of treatment is to resuscitate, stabilize and sustain the victim. Burn casualties usually stay longer on admission than other patients attracting bills that may require ‘donations’ to pay.

Burns constitute public health hazard and global tragedies. Lost lives are irreplaceable and some properties irretrievable. Monetary losses are only estimated not exactly quantified by individuals, corporate bodies or government. Concerted efforts are recommended as remedies but preventive measures are gold standards.

2.0 CHAPTER TWO

TYPES OF BURNS

2.1 BURNS FROM FIRES

B urns from fires or flame burns occur frequently and the extent of structural injury depends upon several factors including the intensity of heat tissue affected. The conductance of the tissues affected determines the rate of dissipation or absorption of heat. Operating factors are the peripheral circulation, water content of the tissue, thickness of the skin and its pigmentation, of the presence or absence of external insulting substances such as hair and skin oil. Of these factors the most important in determining the degree of injury is the peripheral circulation. The rate of blood flow through the heat-exposed tissues can be altered rapidly. This mechanism is of major importance in determining the amount of cellular destruction associated with the transfer of heat to the tissue. Flame burns occur through ignition of clothing from unguarded gas and electric fires, open coal fires, explosion of paraffin and petrol ignited bonfires, car fires following road traffic accidents, car radiator-related burns, stored petrol in homes, and smoking in petrol stations and generators.

Thermal injury due to hot air is rare. For such a burn to occur, the air stream from some form of artificial heat source such as a hair drier or fan heater has to be concentrated on a localized area of the victim’s body. The source has to be close enough to the skin to raise the temperature sufficiently to cause injury. During an epileptic fit, victims are susceptible since they cannot remove themselves from the source.

Hot metal burns are not rare. Burns due to molten metal occur in men working in foundries. In the typical injury, the molten metal is splashed or spilled onto the legs and some of it may run down inside the boots, causing burns of the feet. Home radiators and hot pipe are other sources of burn injury and may result in full skin structural burn. The elderly along with children and people with handicaps are at increased risk in the normal domestic environment..

Burns occur by the use of cigarettes and oxygen therapy especially with admitted patients. Most scald injuries are considered to be home accidents involving tea, coffee or boiling water. Although simple precautions could virtually eliminate this major cause of burn mobidity, there is little evidence that the incidence of tap water scald burns has decreased significantly. It seems clear that the young, the elderly and black skinned people are the groups at highest risk for tape water scald burn injury, whether fatal or not.

Injuries due to accidental contact with steam are occasionally encountered. This type of injury can result in serious work-related disability. Blistering and slough of the bronchial mucosa are common. The severity of injury depends on the temperature of the steam, duration of exposure, distance of the victim from the source of the steam and the ability of the worker to escape the steam.

Elderly people are particularly at risk of accidents in the home. Domestic hot water burns are a common and preventable cause of injury. Elderly people tend to have reduced mobility that result in slower reaction times, making them more susceptible to scalds. The elderly people suffer increased mortality and morbidity and a reduction in independence, even after minor burns. Partial thickness burns in adults can occur in thirty seconds at a temperature of 55oC, five seconds at 60oC and one second at 65oC. Elderly people have thin skin and poor microcirculation, hence heat is removed from burned tissues rather slowly when compared to younger adults, often resulting in scalds that are more serious. Hot water should be stored at a temperature of greater than 60oC to avoid infection by organisms that thrive at low temperatures. In facilities with body immersion, showers and baths there should be thermostatic mixers, located in the hot water system before the tap, which cut off hot water in less than one second at temperature above 45oC.

The mechanism of burn injury is one of the most important determinants of the severity of tissue damage by burn. Although only hot liquid burn is regarded as scalds, the burn caused by liquids with higher boiling point such as certain oils, can cause significantly deep burn injury. The other important determinant of the severity is the contact period as in case of immersion scalds.

Earthquake related burns occurs along with wide-scale destruction of buildings and infrastructures. Disruption of gas, fuel pipes, tankers and multiple home fires lead to fire related death.

Quick freeze injury or frost bite following exposure to cold liquids and gases at extremely low temperature is an occupational hazard. This occurs with liquid helium at -273oC and vapour at -269oC to -180oC. Cold injuries due to accidental leakage of nitrous oxide, frostbite following recreational use of nitrous oxide and gas are possibilities, others are injuries caused by the use of liquid nitrogen, liquid propane, quick freeze injury by spray containing propane and butane as propellants and frostbite injury to the oral cavity with inhaled aerosolized propane propellant.

The widespread use of pressurized aerosol cans and subsequent disposal in domestic and public burnable trash is a source of superficial flash burn. A prominent warning of the fire and explosive hazard of these cans on the front side of the can as well as increased public awareness of the potential dangers of these containers, would be helpful in decreasing the incidence of these injuries.

Burns can also be sustained by standing or walking barefoot on the street especially during the summer months when the ground temperature is estimated to be in the range of 50-60C. Burn injuries that involve the sole