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hypotension, tachycardia, and oliguria with a high CVP (presenting as distendedneck veins). Treat ment acutely consists of pharmacologic circulatory support,followed by attempts to restore perfusion and/or cardiac function. Differentialdiagnosis is essential, because additional fluid and blood administration in thissetting could be lethal, as the failing heart becomes easily overloaded.Neurogenic/spinal shock is often associated with low BP and bradycardia. It canalso result in circulatory collapse. Patients are flushed, “pink and warm” with alow CVP. Treatment with phenylephrine and fluids is aimed at filling dilatedveins and restoring peripheral resistance.http://ebook2book.ir/

DISABILITY (D)Neurologic evaluation (disability) is also an important component of the PrimarySurvey. Key points include assessing for the patient's ability to move allextremities, looking for gross defects. Level of consciousness, usually graded bythe Glasgow Coma Score (GCS) is also performed and documented.http://ebook2book.ir/

EXPOSURE (E)Staying aware of modesty at all times, remove the patient's clothing to allow fora thorough physical examination. Check for signs of trauma, bleeding, skinirritations, needle marks, and warm body temperature.http://ebook2book.ir/

SECONDARY SURVEYAfter the ABCs have been evaluated and any immediate life-threateningemergencies addressed, trauma evaluation continues with the secondary surveywhich is composed of a complete physical exam to evaluate for occult injuriesfollowed by chest x-ray and pelvic x-ray (although many include chest x-ray,pelvis x-ray, and FAST as part of the primary survey under “C,” to identifylocation of hemorrhage). The secondary survey may be augmented with furtherimaging studies depending on the mechanism of injury and findings onexamination. Any change that occurs requires complete re-evaluation, includingrechecking that there has not been a change in the ABCs.http://ebook2book.ir/

A REVIEW FROM HEAD TO TOEHEAD TRAUMAPenetrating head trauma as a rule requires surgical intervention and repair ofthe damage, although brain gunshot wound (especially transcranial gunshotwounds) are frequently lethal.Linear skull fractures are left alone if they are closed (no overlying wound).Open fractures require wound closure. If comminuted or depressed, treat inthe OR.The threshold for obtaining a brain CT should be very low. Almost anyonewho has lost consciousness or has GCS 13-14 should undergo CT imaging.Those with positive findings should get a neurosurgical consult, while thosewith normal findings who are neurologically intact (GCS 15) can beconsidered for discharge if they are able to be accompanied by family/friendsfor the next 24 hours.Basilar skull fractures can be difficult to diagnose. Signs of a fracture affectingthe base of the skull include raccoon eyes, rhinorrhea, otorrhea or ecchymosisbehind the ear (Battle’s sign). CT scan of the head is required to rule outintracranial bleeding and should be extended to include the neck (withreconstruction) to evaluate for a cervical spinal injury. Expectant management isthe rule and antibiotics are not usually indicated.Traumatic brain injury (TBI) from trauma can be caused by 3 components:Initial blow/direct injuryhttp://ebook2book.ir/

Intra-cranial bleeding resulting in a hematoma that displaces the brainstructures (e.g., compression of brain parenchyma, midline shift)Development of increased intracranial pressure (ICP) due to cerebral edemaThere is no treatment for the first (other than prevention), surgery can relieve thesecond, and medical measures can prevent or minimize the third.Acute epidural hematoma occurs with modest trauma to the side of the head,and has a classic sequence of trauma, unconsciousness, followed by a lucidinterval (a completely asymptomatic patient who returns to his previousactivity), gradual lapsing into coma again, fixed dilated pupil (90% of the timeon the side of the hematoma), and contralateral hemiparesis with decerebrateposturing. CT scan shows a biconvex, lens-shaped hematoma, typically in thefronto-temporal area. Emergency craniotomy produces a dramatic cure. Becausemost patients with a history of having been unconscious get a CT scan, the fullblown picture with a fixed pupil and contralateral hemiparesis is seldom seen.Acute subdural hematoma (SDH) also arises from a blow to the head, but theforce of the trauma is typically much larger and the patient is usually muchsicker (not fully awake and asymptomatic at any point), due to more severeneurologic damage. CT scan will show semilunar, crescent-shaped hematoma. Ifmidline structures are deviated, craniotomy to evacuate the blood is indicated,but the prognosis is frequently poor. If there is no deviation, therapy is centeredon preventing further damage from subsequent increased ICP.Invasive ICP monitoring, head elevation, modest hyperventilation, avoidance offluid overload, and diuretics such as mannitol or furosemide can decrease ICP.However, do not diurese to the point of lowering systemic arterial pressure, ascerebral perfusion pressure mean arterial pressure minus intracranialpressure. Hyperventilation is recommended when there are signs of herniation,http://ebook2book.ir/

and the goal is PCO2 35 mm Hg. Sedation is used to decrease brain activity andoxygen demand. Moderate hypothermia is currently recommended to furtherreduce cerebral oxygen demand.Diffuse axonal injury occurs in more severe trauma secondary to anoxia ordecreased cerebral perfusion. CT scan shows diffuse blurring of the gray-whitematter interface and multiple small punctate hemorrhages. Since there is not adiscrete hematoma, there is no role for surgery. Therapy is directed at preventingfurther damage from increased ICP.Chronic subdural hematoma (SDH) may be seen in the setting ofunrecognized subdural or expansion of acute SDH that was not drained. Chronicsubdural hematoma may develop from minor trauma, often in older individualswith underlying brain atrophy, from a tear of the venous sinuses. Over severaldays or weeks, mental function deteriorates as hematoma forms. Neurologicsymptoms may arise from a sub-clinical hematoma as the red blood cells lyseleading to osmotic expansion of the fluid collection. CT scan is diagnostic, andsurgical evacuation provides dramatic improvement.Hypovolemic shock cannot happen from intracranial bleeding: there isn’tenough space inside the head for the amount of blood loss needed to produceshock. Look for another source.http://ebook2book.ir/

NECK TRAUMAFor the purpose of evaluating penetrating neck trauma, the neck has beendivided into 3 zones.Zone 1 begins at the clavicles and extends to the level of the cricoid cartilageZone 2 is located between the cricoid cartilage and the angle of the mandibleZone 3 runs from the angle of the mandible to the base of the skullSurgical exploration for penetrating trauma to the neck is indicated in caseswhere there is an expanding hematoma, deteriorating vital signs, and signs ofesophageal or tracheal injury such as coughing or spitting up blood.For injuries to zone 1, evaluate with CTA and neck CT esophagogram (watersoluble, followed by barium if negative), esophagoscopy, and bronchoscopyto help decide if surgical exploration is indicated and to determine the idealsurgical approach.Historically, all penetrating injuries to zone 2 mandated surgical exploration,with a recent trend toward selective exploration based on physical exam andimaging studies.If the patient is stable with low index of suspicion of a significant injury,use CTA and neck CT to potentially avoid unnecessary surgicalexploration.If the patient’s condition changes or deteriorates urgent surgicalexploration is indicated.For injuries to zone 3, evaluate with CT angiography to identify any vascularinjury.http://ebook2book.ir/

In all patients with severe blunt trauma to the neck, the integrity of the cervicalspine has to be ascertained. Unconscious patients and conscious patients withmidline tenderness to palpation should be evaluated initially with CT scan,potentially followed with MRI depending on findings. Conscious patients withno symptoms (are not intoxicated, have not used drugs, or have no ‘distracting’injury) can be clinically evaluated for a cervical spinal injury; however if CTscan of the head is being obtained, it is generally accepted to extend the study toinclude the cervical spine.http://ebook2book.ir/

SPINAL CORD INJURYThe level and mechanism determine the impact of quality of life and thepotential for recovery. Transection of the spinal cord results in irreversiblecomplete loss of motor and sensory neurologic function below the level of theinjury. With high spinal cord injury, loss of sympathetic innervation and theresulting vasodilation (and in many cases, loss of sympathetic cardiac drive) canresult in neurogenic/spinal shock. Spinal shock should be considered in the acutetrauma setting if there is hypotension and paralysis, often accompanied bybradycardia.A few specific conditions related to spinal cord injury follow.Complete transection is unlikely to be on the exam because it is too easy:nothing works, sensory, or motor, below the level of the injury.Hemisection (Brown-Sequard) is typically caused by a clean-cut injury such asa knife blade, and results in ipsilateral paralysis and loss of proprioception alongwith contralateral loss of pain perception below the level of the injury.Anterior cord syndrome is typically seen with burst fractures of the vertebralbodies. There is loss of motor function, pain and temperature sensationbilaterally below the injury, but vibratory and positional sense are preserved.Central cord syndrome occurs in the elderly with forced hyperextension of theneck, such as a rear-end collision. There is paralysis and burning pain in theupper extremities, with preservation of most functions in the lower extremities.http://ebook2book.ir/

Management necessitates precise diagnosis of a cord injury, best done with MRI.There is some evidence that high-dose corticosteroids immediately after theinjury may help, but that concept is still controversial. Further surgicalmanagement is too specialized for the exam.http://ebook2book.ir/

CHEST TRAUMARib fractures can be deadly in the elderly, because pain impairs respiratoryeffort, which leads to hypoventilation, atelectasis, and ultimately, pneumonia. Toavoid this cycle, treat pain from rib fractures with a local nerve block or epiduralcatheter, in addition to oral and IV analgesics.http://ebook2book.ir/

Figure I-1-1. X-ray of Multiple Rib Fractures due to TraumaCopyright 2007 Shout Pictures - Custom Medical Stock Photo. All rights reserved.Simple pneumothorax results from collapse of the lung. Mechanisms includepenetrating injury, rib fracture with puncture of lung, and secondary iatrogeniccauses (e.g., CVC placement). There is typically moderate shortness of breathwith absence of unilateral breath sounds and hyperresonance to percussion.Diagnosis is confirmed with chest x-ray, and management consists of chest tubeplacement.Hemothorax occurs when blunt or penetrating injury results in bleeding into thechest cavity. The blood can originate directly from the lung parenchyma or fromthe chest wall, such as an intercostal artery. Physical examination revealsdecreased breath sounds on the affected side, accompanied by dullness topercussion. Diagnosis is confirmed with chest x-ray. Chest tube placement isnecessary to enable evacuation of the accumulated blood to prevent latedevelopment of a fibrothorax or empyema, but surgery to stop the bleeding issometimes required. If the lung is the source of bleeding, it usually stopsspontaneously as it is a low pressure system.In some cases where a systemic vessel such as an intercostal artery is the sourceof bleeding, thoracotomy is needed to stop the hemorrhage. Indications forthoracotomy include:Evacuation of 1,500 mL when the chest tube is insertedCollecting drainage of 1 L of blood over 4 hours, i.e., 200mL/hrhttp://ebook2book.ir/

Severe blunt trauma to the chest may cause obvious injuries such as ribfractures with a flail chest or sucking chest wound, as well as less apparentinjuries such as pulmonary contusion, blunt cardiac injury, diaphragmatic injury,and aortic injury.Sucking chest wounds are obvious from physical exam. If there is a flap thatsucks air with inspiration and closes during expiration it could lead to a tensionpneumothorax. A sucking chest wound can also arise from an openpneumothorax, where a larger open wound leads to the inability to exchange airon the side of the injury. Initial management is with a partially occlusivedressing secured on 3 sides, with one open side acting as a one-way valve. Thisallows air to escape but not to enter the pleural cavity (to prevent iatrogenictension pneumothorax).Flail chest involves fracture 3 ribs with 2 segments broken. This allows asegment of the chest wall to retract during inspiration and bulge out duringexpiration (so-called, “paradoxical breathing”). The real problem is theunderlying pulmonary contusion. A contused lung is very sensitive to fluidoverload, thus treatment includes fluid restriction and aggressive painmanagement. Pulmonary dysfunction may develop, thus serial chest x-rays andarterial blood gases have to be monitored.Pulmonary contusion may be detected immediately after chest trauma with“white-out” of the affected lung(s) or can be delayed up to 48 hours. Significantforce is necessary to result in a flail chest, so traumatic dissection or transectionof the aorta should be evaluated for using a CT angiogram. Finally, ARDS maydevelop in this scenario.Blunt cardiac injury should be suspected with the presence of sternal fractures.ECG monitoring will detect any abnormalities. Although serum troponin levelhttp://ebook2book.ir/

was historically obtained, elevations do not generally change management andare therefore not indicated, and treatment is focused on the complications of theinjury such as arrhythmias.Traumatic rupture of the diaphragm shows up with the bowel in the chest (byphysical exam and x-rays), almost always on the left side (the liver protects theright hemidiaphragm). If diaphragmatic injury is suspected it should beevaluated with laparoscopy, although gas insufflation of the peritoneum maycomplicate anesthetic care. Surgical repair is typically done from the abdomen.Traumatic rupture of the aorta is the ultimate “hidden injury.” It mostcommonly occurs at the junction of the arch and the descending aorta where therelatively mobile aorta is tethered by the ligamentum arteriosum. Such an injurycan occur in the setting of a significant deceleration injury and may be totallyasymptomatic until the hematoma contained by the adventitia ruptures resultingin rapid death. Aortic injury should be suspected if:Mechanism of injury, high energy deceleration mechanismWidened mediastinum on chest x-ray or mediastinal hematoma on chest CTPresence of atypical fractures such as the first or second rib, scapula, orsternum, all of which require great force to fractureDiagnosis is made with CT angiogram. Surgical repair is indicated once thepatient has been stabilized and more immediate live-threatening injuries havebeen managed. Repair of aortic injury can be done in an open or endovascularfashion.Traumatic rupture of the trachea or major bronchus is suggested by thepresence of subcutaneous emphysema in the upper chest and lower neck, or by alarge “air leak” from a chest tube. Chest x-ray and CT scan confirm the presencehttp://ebook2book.ir/

of air outside the bronchopulmonary tree, and fiberoptic bronchoscopy mayidentify the injury and allow intubation past the injury to secure an airway.Surgical repair is indicated.Differential diagnosis of subcutaneous emphysema also includes rupture of theesophagus and tension pneumothorax.Air embolism can produce sudden cardiovascular collapse and cardiac arrest. Itshould be suspected when sudden death occurs in a chest trauma patient who isintubated and on a respirator. It also can occur in a spontaneously breathingpatient if the subclavian vein is opened to the air (e.g. supraclavicular nodebiopsies, central venous line placement or lines that becomedisconnected). Immediate management includes cardiac massage, with thepatient positioned in Trendelenburg with the left side down to “trap” air in theatria until it can be absorbed or aspirated. Prevention of air embolism includesuse of the Trendelenburg position when the great veins at the base of the neckare to be accessed.Fat embolism may also produce respiratory distress in a trauma patient who iswithout direct chest trauma. The typical setting is the following:Patient with multiple traumatic injuries (including several long bonefractures) develops petechial rashes in the axillae and neck; fever,tachycardia, and low platelet countAt some point patient develops a full-blown picture of respiratory distress,with hypoxemia and bilateral patchy infiltrates on chest x-rayThe mainstay of therapy for fat embolism is respiratory support. Other therapiesfor this syndrome including heparin, steroids, alcohol, or low-molecular-weightdextran have been discredited.http://ebook2book.ir/

ABDOMINAL TRAUMAFor the sake of evaluation and management, abdominal trauma is divided intopenetrating and blunt trauma based on the mechanism of injury. Penetratingtrauma is further differentiated into gunshot wounds and stab wounds as thepattern of injury based on mechanism is quite different.Gunshot wounds to the abdomen require exploratory laparotomy forevaluation and possible repair of intra-abdominal injuries, not to “remove thebullet.” Any entrance or exit wound below the level of the nipple line isconsidered to involve the abdomen.Stab wounds allow a more individualized approach. “Selective management”with close observation of hemodynamically stable patients can avoid nontherapeutic laparotomy. However, the presence of protruding viscera or thedevelopment of peritoneal signs/evidence of ongoing bleeding requiresexploratory laparotomy.In the absence of the conditions above, local wound exploration may beperformed in the ED to assess whether or not the anterior rectus fascia has beenpenetrated.If the fascia is not violated, the intra-abdominal cavity likely has

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