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Assessment. All patients should be removed of clothing from head to toe. This allows for complete visualization of the entire body surface, which helps to limit missed injuries. Chemical and enviromental contamination and chemical burning is also lessened by removing contaminated clothing.

Treatment. Hypothermia must be addressed rapidly to avoid complicating the patient's hemodynamic status. Heated blankets, warmed IV fluids, and raising the ambient room temperature are excellent ways to limit hypothermia.

Secondary survey. After the primary survery is complete and immediate life -threatening manuevers are under way, the physcian should perform a detailed head-to -toe assessment to evaluate minor injuries and to diagnose occult life - or limb -threatening injuries. In brief, the physcian should place a finger or instrument in every orifice. Constant reevalutation of the patient's ABCDE's is vital (see C I 5).

Head and neck . Pupil size and character, tympanic membranes, and facial stability should all be assessed. Fractures should be evaluated for airway compromise. Rhinorrhea and otorrhea should be suspected with clear drainage. Raccoon eyes and Battle's sign indicate a base of skull fracture. Computed tomography (CT) is the imaging of choice for these injuries.

Thorax. Tension pnuemothorax and massive hemothorax are often diagnosed and treated on the primary survey. Pulmonary contusion, rib fractures, small effusions, and small pneumothoraxes are found on chest radiographs, which should be performed early on during the resuscitation.

Tamponade is decreased cardiac output secondary to poor right ventricular filling that is impaired by fluid (blood) around the heart.

Echocardiography is a noninvasive means to look for pericardial fluid and right ventricular collapse.

Pericardial window is a surgical procedure where the pericardium is directly visualized from a subxyphoid approach.

Pericardial centesis should only be used to decompress a tamponade that is awaiting surgery.

Blunt aortic tears and penetrating great vessel injury

Chest x-ray. Widened mediastinum, deviation of nasogastric (NG) tube, depressed left mainstem bronchus, pleural cap, blurring of aortic knob, and first and second rib fractures all could indicate great vessel injury. Knowing the mechanism of injury is important because the chest x-ray can also be normal.

Transesophageal echocardiography , which is operator dependent, is useful as a screening tool while the patient undergoes emergent surgery.

Angiography is the gold standard. May be replaced eventually with CT or magnetic resonance (MR) angiography.

Esophageal perforation must be evaluated with esophagoscopy and contrast swallow.

Abdomen. Assessment of the abdomen for intracavitary injury can be difficult on the polytrauma patient. Subtle exam findings are often masked due to pain from extremity or spine fractures. Patients may be under the influence of various drugs and alcohol, making the exam unreliable. Tests for abdominal injury are chosen based on the injury pattern, stability of the patient, and index of

suspicion.

Diagnostic peritoneal lavage is an invasive test in which a surgeon places a catheter in the peritoneal cavity and irrigates with 1 L of saline. The test is considered positive if the fluid cell count is greater than 100,000 red blood cells or greater than 500 white blood cells or if vegetative matter or bacteria is present. The lavage is sensitive but not specific to the organ injured.

Ultrasound is a noninvasive exam performed by the trauma surgeon in the emergency department. The study is quick and sensitive but not specific.

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CT scan is a noninvasive test with excellent sensitivity and specificity. The exam is also the only modality that evaluates the retroperitonium. The test often requires transfer of the patient out of the resuscitation area.

Surgery. Once ongoing bleeding or perforation is diagnosed, prompt laparotomy should be performed. Solid organ injury (liver/spleen) can be managed nonoperatively, depending on the clinical situation in relatively stable patients.

Genitourinary injuries (see Chapter 25, VII)

Urethral injury

Blood at the meatus is an indication for retrograde urethrography. Even gentle insertion of a Foley catheter can disrupt a partially divided urethra.

Major injuries should be repaired surgically.

Bladder injuries usually heal spontaneously if adequate urinary drainage is established. (Generally, intraperitoneal bladder ruptures require operative repair.)

Kidneys are commonly injured organs.

Most renal injuries can be managed nonoperatively; however, renal pedicle disruption or major parenchymal damage with hemorrhage are the primary indications for surgery.

Intravenous pyelography provides a good test of renal function, but it is not adequate for determining anatomic continuity of the organ. Extravasated contrast medium is an indication for drainage of the area where the leakage occurred.

Soft tissue injuries

Debridement is the key to avoiding infection and promoting rapid healing.

All devitalized tissue must be removed during debridement.

It is helpful to understand how different tissues respond to injury. The degree of injury often depends on the density of the tissue and its water content.

The lung tends to receive relatively minor degrees of damage remote from the missile tract.

By contrast, muscle or liver, because of their greater density and water content, develop large temporary cavities and require extensive debridement beyond the apparent missile tract.

Muscle

Wide areas of devitalized tissue occur in high-velocity wounds and require debridement.

Viable muscle tissue visibly contracts when touched with an electrosurgical instrument set on a low power. It also contracts when gently pinched with forceps.

Muscle that does not react must be removed, although weakness and deformity will result.

Arteries

Palpable pulses do not rule out arterial injury.

Grossly injured vascular areas that exhibit intramural bleeding or disruption require removal. It is not necessary to remove apparently normal areas of arteries.

Repair should be done with autogenous material, if at all possible. There is an increased incidence of infection and failure when prosthetic material is used (see Chapter 7, VIII ).

Fasciotomies are almost always required in conjunction with vascular repair if there has been prolonged ischemia or concominant venous injury. It is far better to do a fasciotomy early in anticipation of swelling and tension in muscle compartments than to wait until tissue loss has occurred.

Stab wounds and missile tracts in proximity to major vascular structures require either surgical exploration or, at a minimum, emergency arteriography.

Major veins should be repaired when injured.

Nerves. It is not necessary to debride nerves that are injured. Exposed nerves should be covered with normal muscle or fat, leaving definitive repair for a future time.

Bone. Contaminated small pieces of bone that are not attached to soft tissue may be removed. Attached bones should generally be left in situ to speed healing.

Lung tissue is usually resistant to remote damage. Because of its spongy nature, the lung absorbs shock without injury, so a missile tract generally contains all of the injury.

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Parenchymal organs , such as the liver and kidney

Bleeding is the major problem. Devitalized tissue should be removed with as much functional tissue left as possible.

An effort should be made to salvage an injured spleen , particularly in a child. There is evidence that a small spleen slice, reimplanted in the omentum, will grow and provide some splenic function.

Genitalia. Very conservative debridement is indicated. Exposed testicular tissue should be covered with scrotal skin or reimplanted under attached skin, if possible.

Fractures (see Chapter 28, II A 3)

A fracture is seldom a major priority in the presence of other life -threatening injuries.

Hemorrhage or vascular compromise associated with a fracture gives it a higher priority, as does a threat to the viability of an extremity.

Bleeding associated with a fracture can account for a large portion of a patient's circulating blood volume, and hypovolemic shock is commonly associated with bilateral femoral fractures.

Early fractures that are open can be treated in accordance with the associated soft tissue injury.

Debridement, vascular repair, and other soft tissue surgery should be performed before stabilization of the fracture.

However, adequate splinting and stabilization should be accomplished because it decreases the risk of fat embolism syndrome.

Internal fixation devices are generally hazardous in the presence of extensive soft tissue injury and should be avoided, if possible.

Tendon injuries require conservative debridement only. Tendons should be covered with normal tissue; otherwise, they become devitalized and useless.

Special situations

Pediatrics. Young children have different injury patterns due to their pliable skeletons and head-to -body ratio. Intravenous access is sometimes difficult and requires intramedullary access. Pediatrics should be involved early in the management.

Pregnancy. Assessment and treatment is directed toward the mother, as her health is primarily important to the fetus. Early obstetrical input as well as fetal ultrasounds and monitoring are vital. Emergent cesarean section for fetal deterioration is performed in conjuction with the trauma surgeons. Elevation of the right hip displaces the gravid uterus from the inferior vena cava for increased cardiac return.

Transfer to definitive care. After the initial resuscitation, all patients who have injuries or suspicion of injury that exceeds the institution's capability should be transferred. Physician -to -physician transfer to state -accredited trauma centers is optimal. Most hospitals have preexisting transfer agreements.

D Trauma severity scoring and quality assurance

Trauma centers are required to maintain trauma registries, which are used for quality assurance and center accreditation. It is necessary to provide an objective means of identifying patients whose injuries were apparently not of sufficient magnitude to justify death or a poor outcome (i.e., unexpected deaths). It is also helpful to identify patients who have survived injuries that predictably should have caused death (i.e., survivors). The scoring systems are based on anatomic or physiologic data.

The revised trauma score (RTS) is the most commonly used physiologic estimate of injury.

The RTS is based on the GCS , systolic blood pressure, and respiratory rate (Table 21 -3).

The RTS ranges from 1 to 8. A score of 4+ is associated with a probability of survival of 60%.

The GCS (Table 21 -2) is uniquely important and is a key component of RTS. It is important to the secondary survey.

The anatomic score is based on the abbreviated injury scale (AIS), which is a list of hundreds of injuries assigned values of 1 (minor) to 6 (usually fatal).

The AIS is summarized in the injury severity score (ISS). The ISS is calculated by summing the squares of the three highest AIS scores in different regions: head/neck, face, throat, abdomen and pelvis, intestines, and external.

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TABLE 21-3 Glasgow Coma Scale

1.Eye opening

Spontaneous________________ 4 To voice____________________ 3 To pain_____________________ 2 None_______________________ 1

2.Verbal response

Oriented___________________ 5 Confused___________________ 4 Inappropriate words__________ 3 Incomprehensible sounds______ 2 None_______________________ 1

3.Motor response

Obeys commands_____________ 6 Localizes pain_______________ 5 Withdraw (pain)_____________ 4 Flexion (pain)_______________ 3 Extension (pain)_____________ 2 None_______________________ 1

Total Glasgow Coma Scale points (1 + 2 + 3) ________

The ISS ranges from 1 to 75. An AIS 6 injury receives an ISS score of 75. An ISS in the 40+ range is associated with approximately a 50% survival.

The above methodology (i.e., trauma score and ISS) is combined in outcome evaluation using the trauma and injury severity score (TRISS) methodology (Fig. 21 -1)

Revised trauma score (RTS) is plotted against ISS (Fig. 21 -1), and a 50% probability of survival (PS) isobar is drawn.

Deaths should be above the PS 50 isobar, and survivors below it. Outliers are cases worthy of audit; they are not necessarily truly unexpected survivors or deaths unless the audit confirms the TRISS - predicted outcome.

Many statistical methods have been developed to compare the probable outcome of a given injury to the actual outcome seen in the trauma center. The ultimate statistical tool has yet to be developed.

FIGURE 21-1 “TRISS” methodology combines the revised trauma score and the injury severity score. Deaths are plotted above the 50% probability of survival (PS 50) isobar, whereas survivors fall below the isobar. However, there are some unexpected deaths, which are plotted below the PS 50 isobar, and some unexpected survivors, which are plotted above the PS 50 isobar.

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II Burns

A Overview

The initial treatment of burns is based on the same principles and priorities as for other forms of trauma (see I A 2 b [1]). However, one special priority is to stop any continuing burn injury caused by smoldering clothes or corrosive chemicals by using neutral solutions to flush away all garments from the injured area. It is also mandatory to assess any concomitant injuries. The management of the burned patient depends on the depth, extent, and location of the burned area. Transfer of the burn patient to a burn center or consultation with the center should be considered for all but minimal burn injuries.

Depth of burns

First -degree burns (involvement of epidermis only). Clinical findings are limited to erythema.

Second -degree (partial -thickness or intradermal) burns

Clinical findings include vesicles, swelling, and a moist surface.

Partial -thickness burns are painful and are hypersensitive to a light touch or even the movement of air.

Epithelial remnants (skin appendages) are spared.

Intravenous fluid resuscitation is required for all partialor full -thickness burns extending over 20% or more of the BSA.

Location of burns

Inpatient treatment is required for secondor third -degree burns of the face, hands, feet, or genitalia.

Secondor third -degree burns involving major flexion creases usually require hospital treatment to minimize contractures and other late problems.

Second and third -degree burns exceeding 20% BSA.

B Airway control and ventilation

Airway obstruction may develop rapidly after inhalation injury or may be delayed. Delayed airway obstruction is due to progressive swelling and is apt to develop 24–48 hours after the injury. The possibility should be suspected if any of the following conditions are present:

A history of being burned in a confined space

A facial burn or singed facial hair

Charring or carbon particles in the oropharynx

Carbonaceous sputum

Circumferential burns of the trunk, especially those with a thick eschar (which may require emergency excision—see II D 5)

Measurement of arterial blood gases (see Chapter 1, VII C 5 f ) is indicated as well as measurement of carbon monoxide level (carboxyhemoglobin value over 10% is significant) (Rx: F i O 2 100%).

Endotracheal intubation should be performed before the patient develops respiratory problems. Intubation is preferable to a tracheostomy in the patient with burns of the face, neck, or respiratory tract because tracheostomy through a burn carries a high mortality.

C Circulatory support and fluid resuscitation

Major burns—those involving 20% or more of the BSA—call for fluid resuscitation.

Intravenous fluids should be administered through a 14 - or 16 -gauge intravenous catheter.

The catheter may be placed through the burn wound, if required.

Intravenous fluids should not be given via a lower extremity because the site is prone to sepsis and its increased mortality risk.

Fluid resuscitation should begin with lactated Ringer's solution.

The volume to be given is calculated as follows:

For adults: % BSA burned × kg body weight × 2–4 mL electrolyte solution

For children: % BSA burned × kg body weight × 3 mL electrolyte solution