دپارتمان سوختگي امام رضا(ع) - آرشیو 1391/10

Resuscitation

Along with early excision and grafting, one of the central tenets of current

burn care is fluid resuscitation of the burn victim. Many different methods have

been proposed, all valid, but with no universal acceptance for one formula. They

vary in their use of crystalloid and colloid components and are in continuing

evolution as we understand the pathophysiology of the burn wound better. The

most important principle in burn resuscitation is that any of these formulas are

only guidelines and individual fluid requirements are to be judged by clinical and

hemodynamic parameters as endpoints. Without adequate resuscitation, tissue

perfusion suffers and the burn shock cascade is perpetuated. Delay to adequate

resuscitation is one of the factors identified with increased mortality.

One of the many functions of the skin is to maintain fluid and electrolyte hemostasis.

After burn injury, the integrity of skin is lost and leakage of plasma occurs.

This is complicated by edema secondary to loss of endothelial integrity and

further sequestration of fluid in tissues not directly affected by the burn itself.

Thermal injuries of greater than 30% have been demonstrated to initiate a cascade

of inflammatory mediators leading to capillary leak that lea ds to the anasarca

in unburned areas and pulmonary edema. These mediators include histamine,

bradykinin, and serotonin but the exact mechanism to initiate the cascade

has not been elucidated. Attempts at modulation of the cascade are reported, but

have not been successfully applied in a clinical setting. Adequate resuscitation aims

to counter these effects and reduce this process of postburn shock.

Intravenous access should be established early in the initial evaluation of the

burn patient after the airway has been secured according to standard trauma protocols.

Peripheral, large bore IVs provide excellent access and can actually administer

greater volumes of fluid due to diminished resistance of the catheter secondary

to a shorter length. Central venous access may be difficult to establish with the

crowding of people around the torso of a newly arrived trauma victim, and also

carry risks of pneumothorax or inability to control bleeding from inappropriate

placement. In children it can be particularly difficult to establish intravenous access,

and the intra-osseous route can be used emergently for fluids and medicines.

Calculations of fluid requirements are based on the amount of body surface

involved in second or third degree burns (not first-degree burns). The “Rule of

Nines” has been used to estimate the body surface area burned (Fig. 3.1), but this

does have limitations in the pediatric population where the head is proportionally

larger than the body when compared to the adult. Modifications of this burn diagram

are available (Fig 3.2) or nomograms are available as well (Fig 3.3) to calculate

body surface area and percent burn. On a more practical note, knowing that

 the patient’s palm (not the examiner’s) is equal to 1% of total body surface, body

surface area (BSA) burned can be estimated by “patting out” the burned areas

when a quick evaluation is needed.