Disclosure
Trauma has been dubbed the forgotten epidemic and the neglected disease of modern society. It kills and maims hundreds of thousands of individuals annually and costs society billions of dollars for direct expenditures and indirect losses. Trauma care has improved over the past 20 years, largely from improvements in trauma systems, assessment, triage, resuscitation, and emergency care. Work must still be done to continuously improve trauma care nationally, regionally, and institutionally. For this improvement to occur, the ongoing application of the unique principles and practice of intensive care medicine is necessary.
Trauma care means the right care at the right time and in the right place. Patient outcomes after major trauma have improved in regions where comprehensive trauma systems have evolved. Crucial components of such a system should include a coordinated approach to both prehospital and hospital care, and to training providers in both areas. Paramedics and medical staff should be provided with a clear and objective framework for assessing patients, establishing treatment protocols, following triage guidelines, engaging in transportation and communication protocols, and implementing ongoing quality-improvement programs. Triage Circumstances may differ from region to region. Therefore, the most seriously injured patients must be identified and safely transported to a designated trauma center where appropriate care is immediately available. This is the principle of triage. Trauma scoring Trauma scoring has emerged as a means of describing injury severity and has become an essential component of quality improvement. Various systems facilitate the prediction of patient outcomes and the evaluation of aspects of care. The scoring systems vary widely, with some relying on physiologic scores (eg, Glasgow Coma Scale [GCS] score, Revised Trauma Score), and others relying on descriptors of anatomic injury (eg, Abbreviated Injury Score, Injury Severity Score). No universally accepted scoring system has been developed, and each system contains unique limitations. This limitation has resulted in the use of a number of such systems in different centers around the world.
Principles involved in the initial assessment of a patient with major trauma are those outlined by the American College of Surgeons (ACS) in their Advanced Trauma Life Support (ATLS) guidelines or those of the Australasian College of Surgeons in the Early Management of Severe Trauma guidelines. The principles involved consist of (1) preparation; (2) primary survey and resuscitation, including monitoring, urinary and nasogastric tube insertion, and radiography; (3) secondary survey, including special investigations such as CT scanning or angiography; (4) ongoing reevaluation; and (5) definitive care (see Neurotrauma, Chest Trauma, Abdominal Trauma, Exsanguinating Pelvic Trauma, and Intensive Care for the Patient with Polytrauma). PreparationTrauma-receiving hospitals should receive advance warning about the impending arrival of seriously injured patients from the paramedic services. The patient's mechanism of injury, vital signs, and status should be communicated. This allows for the in-house trauma team to be called and for the emergency department (ED) staff to make appropriate preparations. The trauma team usually consists of specialists in intensive care (common in Australia, less common in the United States and may be a dual-certified surgeon), surgery, and emergency medicine. A team leader is identified, and it is the team leader's responsibility to ensure that the resuscitation proceeds in an organized and speedy manner through the diagnostic and therapeutic protocols. In addition to the care giving team, many trauma centers will also have present a trauma care coordinator, who will follow the patient through their hospital course. On the patient's arrival, a concise transfer of the patient from the paramedics should occur. One person should be talking, while everyone else is listening; this is crucial information for the whole team. Primary surveyThe primary survey aims to identify and immediately treat life-threatening injuries. Its basis is the ABCDE system. This system comprises airway control with stabilization of the cervical spine, breathing (work and efficacy), circulation including the control of external hemorrhage, disability or neurologic status, and exposure or undressing of the patient while also protecting the patient from hypothermia. Airway with control of the cervical spine Assess the airway, and determine its adequacy while maintaining the cervical spine in the neutral position. The latter is achieved by using a hard collar and, in some cases, sandbags and tape. A chin lift, a jaw thrust, or an oropharyngeal airway maneuver may overcome upper airway obstruction. Suctioning may help to clear the mouth and pharynx of secretions or vomit. Orotracheal intubation is usually necessary when (1) the airway is compromised, (2) oxygenation or ventilation is inadequate, (3) the airway is unprotected, (4) the level of consciousness is decreased (GCS score <8), (5) the patient is combative and at risk of self-injury, (6) immediate loss of the airway is a risk (eg, in patient with large-area burns), and (7) airway control is desired for therapeutic or diagnostic procedures. Airway control is achieved by means of rapid-sequence intubation performed with in-line stabilization of the cervical spine. Correct placement of the endotracheal tube is confirmed (1) with the aid of an end-tidal carbon dioxide monitoring device (2) by observation of the tube passing through the vocal cords, and (3) by auscultation of the chest. Breathing Assess the work of breathing and its efficacy by inspecting the patient and by palpating the trachea. Regarding inspection, ask these questions: (1) Is the patient breathing at all? Is the patient in respiratory distress, tachypneic, grunting, or wheezing or using their accessory muscles? (2) Are signs of disruption to the chest wall evident? (3) Is paradoxical movement of the chest present, and if so, is this associated with a flail chest? On palpation for the trachea, ask these questions: (1) Is crepitus present? (2) Is the trachea located in the midline? On percussion and auscultation of the chest, look for signs consistent with pneumothorax or hemothorax Inadequate respiration may result in hypoxemia, hypercarbia, cyanosis, depressed level of consciousness, bradycardia, or tachycardia. As a general rule, until stability has been assured, administer high-flow oxygen to all patients to help ensure adequate oxygen delivery. Treatment of a patient with immediately life-threatening physiological derangements may delay and in some cases may preclude completing the recommended diagnostic evaluation in the ED. Signs of a tension pneumothorax include a deviated trachea, distended neck veins, hypoxia, tachycardia, and hypotension. Tension pneumothorax is a clinical diagnosis and requires immediate decompression with a 14-gauge cannula in the second intercostal space (ICS) midclavicular line (MCL), to convert this life-threatening complication into a simple pneumothorax, which then can be treated with a chest tube (see Chest Trauma). Circulation and hemorrhage control Urgent treatment of patients with exsanguinating hemorrhage or shock can be lifesaving. This assessment includes identifying and managing rapid external hemorrhage. This can often be achieved with a simple pressure dressing, but surgical intervention may be required in some cases. Shock in trauma patients, defined as inadequate organ perfusion and tissue oxygenation, is most commonly caused by hypovolemia. Shock secondary to tension pneumothorax, cardiac tamponade, or spinal cord injury also may occur. Signs of shock include tachypnea, tachycardia, poor pulse volume, hypotension, pallor, poor capillary refill, oliguria, and a depressed level of consciousness. In patients with hypovolemia, the neck veins may be flat. Healthy mental status generally implies an adequate cerebral perfusion pressure, while diminished mentation may be associated with shock with or without intracranial trauma. During patient assessment, 1 or 2 members of the trauma team must be responsible for inserting at least 2 large-bore (14-gauge) peripheral lines; obtaining relevant bloods, including cross-matching; and initiating volume resuscitation. Initially, patient response to appropriate fluid boluses of 10 mg/kg can be assessed on clinical grounds. The ATLS recommendation for patients presenting with hypotension is a 2000-mL crystalloid volume challenge. A systematic approach for detecting the source of hypovolemic shock should consider 5 sources of ongoing hemorrhage: (1) external (eg, from the scalp, skin, or nose), (2) pleural cavities, (3) peritoneal cavity, (4) pelvis and/or retroperitoneum, and (5) long-bone fracture Ongoing hemorrhage and hypotension may require transfusion with uncrossed matched blood and immediate surgical intervention. In general, hypovolemia unresponsive to an initial 2000-mL fluid challenge implies substantial previous losses or ongoing hemorrhage. Disability During the resuscitation of a patient with trauma, a brief assessment of neurologic status should be performed. This assessment should include the patient's posture (ie, any asymmetry, decerebrate or decorticate posturing), pupil asymmetry, pupillary response to light, and a global assessment of patient responsiveness. The Australasian College of Surgeons and the ACS recommends the AVPU scale as follows: A = Patient is awake, alert, and appropriate. V = Patient responds to voice. P = Patient responds to pain. U = Patient is unresponsive. A more detailed assessment by using the GCS score can be made at this time or during the secondary survey. Exposure Patients should be completely disrobed during the initial assessment and the subsequent secondary survey. This helps ensure that significant injuries are not missed. At the same time, efforts to prevent significant hypothermia by using a warm ambient room (28-30°C), overhead heating, and warmed IV fluids, should be instituted. The patient's temperature should be monitored as early as possible, and strenuous efforts should be made to avoid significant hypothermia. Ongoing monitoring Use of urinary catheters is mandatory after severe injury; however, precautions to avoid urethral injury should be taken for patients with pelvic trauma and for those who have blood at the urethral meatus. Digital rectal examination to identify a high-riding prostate should precede catheter insertion. Abnormal findings from the rectal examination or concern as to the continuity of the urethra should prompt a retrograde urethrocystogram to identify a urethral injury. If this is identified, a suprapubic catheter should be inserted, and a urologist should be consulted. Gastric tubes should be inserted into all major trauma patients requiring endotracheal intubation. If a head injury is suspected, the gastric tube should be passed via the mouth. Children, in particular, are prone to gastric dilatation, which can significantly impair their respiration. Immediate decompression can greatly improve the patient's vital signs. Ongoing monitoring of pulse rate, blood pressure, respiratory rate, and urine output is required. Radiology Initial imaging in the resuscitation room should be limited to a lateral cervical spinal image, anteroposterior (AP) chest radiography, and AP pelvic image. The lateral cervical spinal image to the cervicothoracic junction depicts 90% of cervical lesions. Definitive clearing of the neck is managed in different ways in different institutions. Approaches vary from a 3-part series (lateral cervical spinal, AP, odontoid view) to a 5-point series, with addition of right and left oblique views and flexion and extension views, in a selected group who may have normal radiographs but ongoing pain. CT scanning of the entire cervical spine is now routine at many institutions for patients in whom a clinical assessment is not possible or is scheduled to undergo CT of the head. Chest radiographs should be assessed for the position of tubes and lines, the presence of treatable life-threatening conditions, the causes of shock (eg, pneumothorax, hemothorax), the presence of a widened mediastinum, lung parenchymal injuries, and injuries to the thoracic cage. A high-energy pelvic fracture may substantially contribute to shock and suggests the early need for stabilization or immobilization. Secondary surveyThis survey usually is not started until the immediate life-threatening injuries are addressed and the primary survey is complete. The secondary survey includes a detailed history, complete physical examination, additional indicated x-ray examinations, and special studies (eg, focused abdominal sonography for trauma [FAST], angiography, diagnostic peritoneal lavage [DPL] in rare cases, CT), and laboratory tests. These tests should be conducted in an organized fashion and should prompt the initiation of definitive treatment for identified injuries without delay. Many institutions include the FAST examination as part of the primary survey rather than in the secondary survey. The history should include assessment of the following items, which can be remember by using the AMPLE acronym: A = history of patient's allergies; M = patient's medication history; P = Past medical, surgical and social history; L = Time of last meal; and E = Full description of events leading to injury, scene findings, notable interventions, and recordings en route to the hospital. Examination of the patientHead and face and neurology Inspect the whole head. Look for scalp bleeding, and rapidly suture briskly bleeding lesions. Sutures or clips may be helpful in controlling bleeding from large flaps. Palpate for facial fractures and a mobile middle third of the face. Hemotympanum and the presence of bruising around the eyes (ie, raccoon eyes) and mastoid process (ie, Battle sign) suggest basal skull fractures. Recheck the pupils, and repeat GCS scoring. Evaluate the cranial nerves, peripheral motor and sensory function, coordination, and reflexes. Identify any neurologic asymmetry. All such patients and those with an altered level of consciousness should undergo a head CT scanning. Patients with a traumatic brain injury (TBI) are particularly susceptible to shock and hypoxia and under those circumstances have a greatly increased mortality rate. Neck While the collar is off, an assistant must stabilize the cervical spine to allow the neck to be examined closely. The neck must remain immobilized until the spine can be definitively cleared. Penetrating injuries of the neck may require angiographic, bronchoscopic, or radiologic examination. Chest Reexamine the chest. Initiate further investigations as indicated by physical examination findings or radiography results (eg, CT scan, aortography, or transesophageal echocardiography [TEE]). Abdomen Inspect, percuss, palpate, and auscultate the abdomen, noting tenderness and examining for fullness, rigidity, or guarding. Remember that blood is not always a peritoneal irritant, and hemoperitoneum may occur without obvious external signs. Inspection of the abdomen is confounded by distracting injuries and impaired consciousness from head injury or drugs and alcohol. FAST scans are now routine in the ED and may lead either to definitive operative care or further diagnostic examination by means of CT. DPL is now used on only rare occasions. Limbs Inspect, palpate, and move the limbs to determine their anatomic and functional integrity. Pay attention to the adequacy of the peripheral circulation and integrity of the nerve supply. Arterial insufficiency in patients with a displaced fracture or dislocation requires immediate treatment. Log roll The log roll refers to the slow controlled turning of the patient to assess the dependent part of the supine trauma victim. Care must be taken to avoid secondary injury from an as-yet undiagnosed unstable fracture. This examination concentrates on the back of the head, neck, back, and buttocks, and includes a rectal examination. Some practitioners believe that, in the setting of significant pelvic injury and hemodynamic instability, the potential to destabilize clot formation and to worsen exsanguination outweighs the benefits of log rolling. This procedure should be carried out by at least 4 people. The first person stabilizes the head and neck and manages the airway, the second and third turn the patient, and the fourth inspects and palpates the back. A fifth person could be responsible for guiding the feet and lower extremities. Depending on the mechanism of injury (high-speed motor vehicle accident, acceleration-deceleration injury) and the hemodynamic stability of the patient, imaging of the thoracic and lumbar regions may be performed at this stage of the patient assessment. According to local practice, this may be done by means CT or, more often, by means of traditional AP and lateral radiography performed in the resuscitation room or imaging facility. ReevaluationDuring the secondary survey, the ABCDE system should be used to constantly reevaluate the patient, and an ongoing diagnostic and therapeutic plan should be formulated and updated as required.
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Closed head injury occurs commonly in the setting of major trauma and contributes significantly to poor outcomes. Despite advances in all aspects of trauma care, severe TBI carries a mortality rate of 30%. Conservative estimates place the incidence of closed head injury at 200 cases per 100,000 patients. Predicting the outcome of the best and worst cases is usually possible, but the outcome prediction for patients between these ranges is more difficult. Survivors of severe and moderately severe head injuries are likely to be left with some degree of disability. These may vary from subtle changes in behavior, including depression and loss of independence and earning power, to major sensory and motor deficits, and, at worst, to being rendered vegetative. Treatment principlesThe principles of treatment for a patient with a brain injury apply equally at the time of initial assessment as they do during ongoing inpatient care. These principles are aimed at preventing secondary brain injury. Secondary brain injury symptoms commonly include hypotension, hypoxemia, hypercarbia, fever, seizure, and uncontrolled hyperglycemia. Sound prehospital care has a significant impact on patient outcome. This involves adequate oxygenation and ventilation and the maintenance of an adequate cerebral perfusion pressure. AssessmentPrehospital assessment The initial assessment is the same as for any trauma patient. Immediate protection from secondary injury by avoiding hypoxia and hypotension and preventing hypercarbia improves patient outcome. Early airway control in patients with a clinically significant depressed level of consciousness is essential. Hospital assessment Hospital assessment involves the history of trauma, physical examination, evaluation of posture and pupillary responses, and additional investigations. The history of trauma is gained from the patient, witnesses at the scene, attending ambulance staff, and knowledge of the mechanism of injury. The severity of the injury is defined by carefully examining the patient's mental status by using the GCS score, posture, and pupillary responses. The GCS score quantifies the patient's neurologic status and enables the rapid and uniform communication of the initial assessment of the patient's possible neurologic injury. The GCS score is a familiar descriptor used in the ED. It is derived from observation and responses to eye opening, best motor responses, and best verbal responses (Table). In the absence of confounding factors, such as drugs and alcohol use, a low GCS score is a strong predictor of a poor prognosis. Of the 3 parameters assessed, in trauma, the best motor response elicited is the most accurate prognostic indicator. A GCS score of 3-8 indicates a severe head injury, whereas a score of 14-15 is mild (a GCS score of 15 is normal). GCS Score
Assess the patient's posture and pupillary response. In patients who are comatose, note any decerebrate or decorticate posture and pupillary responses to light (normal response is constriction). As part of an accurate primary and secondary survey, closely examine the entirety of the head, including the ears (tympanic membranes) and face (bony stability, nasal septal hematoma, raccoon eyes, or Battle sign). In addition, a trauma series of plain radiographs should help assess the lateral cervical spine, chest, pelvis, and indicated spinal regions during the secondary survey. Additional noncontrast CT scans (of the brain and selected regions of the spine) should also be performed early in the patient assessment. Spinal images should undergo 3-dimensional reformation to better examine the structural alignment of the vertebral subunits. Although MRI does not have a role in the acute assessment of a patient with trauma and head injuries, it is a sensitive modality for prognostication when subtle or diffuse injuries may be present. However, MRI is rarely used at this stage of the assessment. Operative versus nonoperative treatment in the setting of head traumaIndications for operative intervention are (1) extra-axial collections with mass effect, (2) significant mass effect from contusion or hemorrhage resulting in a shift of intracranial structures, (3) penetrating head injury with necrotic foreign body tracks, (4) removal of a foreign body if it compromises neurologic function, and (5) significantly depressed (>1 cm) skull fractures. Nonoperative or medical therapies are aimed at providing the injured brain with an adequate cerebral perfusion pressure, avoiding hypoxia and hypercarbia, and decreasing the cerebral oxygen demand. Standard medical treatment is described below. Provide adequate oxygenation and ventilation. Ideally, the patient should be ventilated to normocarbia PCO2 of 4.5 kPa or 40 mm Hg. Hypoventilation (PCO2 >40 torr) and severe hyperventilation (PCO2 <30 torr) should be avoided. Care should be taken to avoid interfering with venous drainage from the face and head by not using tight endotracheal tube ties or ill-fitting cervical collars. The patient should be considered, at minimum, euvolemic, and he or she should have a mean arterial pressure (MAP) of at least 90 mm Hg, providing the intracranial pressure (ICP) is less than 20 mm Hg. Otherwise, the MAP may need to be higher to maintain a cerebral perfusion pressure (CPP) of 70-90 mm Hg. Hyperthermia should be avoided. Although no convincing evidence supports the routine use of moderate hypothermia, it is practiced by many units. The best outcomes appear to be in the younger age group of men with TBI. Mannitol 0.5-1 g/kg should be administered only to a patient with lateralizing neurologic findings, a surgically correctable lesion, and en route to the operating room. Otherwise, the routine use of mannitol may lead to intravascular volume depletion and diminished cerebral oxygen delivery due to cerebral hypoperfusion. ICU managementIn addition to those measures listed above, the ICU management team also focuses more specifically on monitoring and treating ICP elevations, manipulating cerebral perfusion, providing adequate nutrition, and controlling metabolism. In addition, an ongoing assessment of the patient's progress can be made through repeated clinical assessments, CT studies, and other hospital or regionally specific advanced monitoring techniques (eg, somatosensory-evoked potentials, positron emission tomography or single-photon emission computed tomography imaging). CPP can be estimated by subtracting the ICP from the MAP. CPP should remain at greater than 70 mm Hg. Cerebral blood flow (CBF), although difficult to measure, is autoregulated in the uninjured state over a wide range of MAPs. TBI uncouples this tightly coupled process such that CBF may not match or be adjusted in parallel with cerebral metabolic consumption of oxygen. This phenomenon is most notable immediately surrounding a zone of injury, but it also may affect uninjured segments. ICP monitoring is useful in titrating therapy to maintain a set CPP range. A normal ICP is 15 mm Hg, yet as much as 20 mm Hg is considered acceptable in a trauma patient. A strong correlation exists between elevations in ICP and a poor cerebral outcome. In the setting of induced coma, indications for ICP monitoring in patients with a closed head injury include monitoring and treating intracranial hypertension, which may lead to further imaging, surgery or medical therapy; managing acute hydrocephalus. Monitoring is also indicated after surgery for the early management of intra-axial or extra-axial collections. ICP can be measured by means of a variety of routes and devices, however, the criterion standard is considered to be a fluid-coupled ventriculostomy catheter inserted into a lateral ventricle. Other devices may be placed into the brain parenchyma; however, these devices do not afford the ability to remove CSF as a treatment for elevations in ICP.
Chest injuries are common and contribute to many deaths. Life-threatening blunt chest injuries may affect the chest wall, lung parenchyma, the great vessels, and the heart itself. Injuries to the heart and great vessels usually result in exsanguinating hemorrhage or shock. Pericardial tamponade, tension pneumothorax, and massive hemothorax can be fatal if not recognized and treated immediately. Ruptured thoracic aorta This condition usually results from deceleration forces. Blunt injuries affecting the ascending aorta usually are rapidly fatal, and few patients with this injury survive long enough to make it to the hospital. Blunt injuries to the descending thoracic aorta are often also rapidly fatal. Of these patients, 85-90% die before they reach the hospital. Of those patients who do survive long enough to be admitted, the mortality rate for those who go untreated is reported to be 1% per hour for the next 48 hours. Although this is commonly quoted, it is based on an old autopsy study. Those patients with major head injuries and / or major lung injuries are often managed medically until they are considered fit for surgery, and often do better as a result. Injuries to the descending thoracic aorta usually occur in the presence of other injuries to the brain, chest wall, lung, abdomen and long bones. The thoracic aorta is fixed at 3 places: the aortic valve, ligamentum arteriosum (most common site of rupture), and diaphragmatic hiatus. Tearing of the aorta occurs during sudden deceleration and results from continued movement of its more mobile portions relative to those that are fixed. Early diagnosis and treatment (medical or surgical) are essential. Diagnosis of descending thoracic aortic injury is typically based initially on clinical suspicion (mechanism of injury), plain chest radiographic findings (widened mediastinum, abnormal mediastinal contour) and is confirmed by aortography (criterion standard), contrast-enhanced CT, or TEE. Features of the plain AP chest radiograph warranting further examination include the following: left apical cap, widening of the mediastinum, loss of the contour of the aortic knuckle, depression of the left mainstem bronchus, loss of the paravertebral pleural stripe, and deviation of the nasogastric tube or esophagus to the right. Regarding treatment, the surgical techniques required for injury repair to the descending thoracic aorta vary from center to center but likely involve hypotensive anesthesia, temporary bypass shunts, or formal pump-assisted bypass. Regardless of the technique used, as many as 8-10% of these patients may develop paraplegia as a result of the injury itself or secondary to vascular compromise of the thoracic spinal cord during the repair procedure. If the patient has an accompanying intra-abdominal injury and a more stable thoracic hematoma, a laparotomy should be the first-choice procedure. Tension pneumothorax Tension pneumothorax is a potentially fatal condition unless immediately diagnosed and treated. Clinical features may include respiratory distress, tracheal deviation (away from the affected side), absence of breath sounds (on the affected side), hyper-resonant percussion note (on the affected side) and distended neck veins. Attendant shock with hypotension and tachycardia may occur. The plain chest radiograph demonstrates lucency on the affected hemothorax and shift of the mediastinum to the unaffected side. It is important to note that tension pneumothorax should be a clinical diagnosis and not a radiological one. Treatment consists of immediate decompression followed by drainage. Decompression can be achieved by inserting a large-bore cannula (14-gauge) into the second ICS in the MCL on the affected side. Drainage is obtained by inserting a large-caliber (32F or larger) chest tube MCL and anterior axillary lines in the fourth or fifth ICS. The chest tube is attached to a pleural drainage device that can maintain an underwater seal and can apply low pressure variable negative pressure throughout the system. Hemothorax Massive hemothorax may result from blunt or penetrating trauma and requires rapid decompression with circulating volume restoration. Clinical signs are hypovolemia, absence of breath sounds (on the affected side), and dullness to percussion (on the affected side). In extreme cases, the AP plain chest radiograph shows a whiteout on the affected side with a contralateral shift of the mediastinum away from that side. The x-ray appearance can be confused with substantial lobar collapse; however, in the case of parenchymal collapse with volume loss, the shift of the mediastinum is classically towards the affected side. Treatment includes adequate volume replacement and simultaneous pleural decompression. Appropriate intravenous access must be established with the insertion 2 large-bore intravenous cannulae (14-16 gauge). Decompression of the hemothorax is accomplished by inserting a large-bore (36F or 40F) chest tube into the pleural space of the affected side. In the setting of ongoing blood loss, crystalloids and colloids should be accompanied by cross-matched packed red blood cells according to local protocols and emerging evidence Surgical intervention is usually indicated if the initial blood loss was 1500 mL or in the setting of ongoing loss of greater than 200 mL/h for 4 h, or any lesser amount in association with ongoing hemodynamic instability. Flail chest Flail chest often occurs secondary to crush injuries involving multiple rib and sternal fractures, resulting in significant disruption to the thoracic cage. As a result of this extremely painful condition, the patient is unable to breathe effectively because of pain and paradoxical chest movement upon inspiration. However, the major problem is with the underlying pulmonary parenchymal injury, not the disrupted bony thoracic cage. Flail chest is clinically diagnosed by the presence of paradoxical chest-wall movement during spontaneous inspiration and palpation of the flail segment in association with crepitus. This is usually associated with trauma, marked respiratory distress and pain. Treatment of patients with a flail chest consists of airway, breathing, and circulatory (ABC) care and control, accompanied by adequate pain relief. Treatment may include narcotic analgesics, nonsteroidal anti-inflammatory drugs (NSAIDs) for patients not considered at risk of renal failure, and epidural analgesics. Adequate pain relief allows for physiotherapy, helps facilitate coughing to permit airway clearance, prevents atelectasis, and maintains adequate respiratory function. Full lung expansion may require temporary intermittent positive-pressure ventilation and as appropriate, pleural drainage. Flail-segment fixation may be considered in selected cases, but it is rarely done. Cardiac tamponade Cardiac tamponade causes shock as inadequate ventricular filling occurs as a result of compression of the cardiac chambers by blood in the pericardial sac. This usually is the result of a penetrating wound to the upper abdomen or chest. Shock can occur acutely, particularly when the pericardial sac fills quickly or more slowly in the setting of subacute bleeding and rebleeding. Classic cardiac tamponade is diagnosed by observing the presence of the Beck's triad. This comprises of elevated central venous pressure, hypotension, and reduced heart sounds on auscultation. This diagnosis must be considered in all patients who suffer penetrating injury to the chest, back and upper abdomen even in the setting of relative hemodynamic stability and positively ruled out in the hemodynamically unstable patient. Treatment: Restoring myocardial function by draining the pericardial collection and by properly treating the patient's underlying cause (eg, cardiac laceration) is essential to ensuring patient survival. Drainage of the collection may be achieved through pericardiocentesis although it should be noted that ATLS and EMST is moving away from teaching pericardiocentesis as it is no longer considered effective. A formal surgical approach is often the best via a pericardial window and if positive proceeding to median sternotomy or thoracotomy (often transverse). Other trauma complications Performing an emergency thoracotomy for the purposes of resuscitation is controversial. However, a resuscitative thoracotomy is indicated in a patient with penetrating thoracic trauma who loses vital signs en route to or in the ED. This procedure permits immediate access to the heart, great vessels and lungs, and facilitates internal cardiac massage, aortic cross-clamping to maintain cerebral perfusion, control of bleeding from pulmonary parenchyma, and pericardial decompression. The use of resuscitative thoracotomy to reduce abdominal injury hemorrhage has not met with great success. Instead, thoracotomy for this indication is associated with nearly uniform mortality. Both blunt and penetrating injury may cause diaphragmatic rupture. Blunt trauma often results in large radial tears of the diaphragm, whereas smaller punctures result from penetrating injuries. Ruptures are more commonly identified on the left, where the diaphragmatic crus is more mobile, compared with the other side, where it is more closely associated with, and protected by, the liver. Bilateral rupture is rare. Right-sided ruptures can be missed initially, only to be diagnosed later, usually as an incidental finding. This diagnosis can be difficult to make. Indeed, many times the diagnosis is made late or missed, and the rupture is detected years later. It is suggested by the presence of abnormal chest movements, acute respiratory distress, and chest radiographic findings that suggest the presence of viscera within the thorax or an abnormally elevated hemidiaphragm. Conclusive diagnosis is confirmed by a variety of means. A simple method is by locating the abnormal position of the stomach above the diaphragm, identified by the presence of a gastric decompression tube. Alternatively, the diagnosis may be established by means of CT scanning, laparoscopy or laparotomy.
Abdominal trauma, both blunt and penetrating, remains a significant cause of patient morbidity and mortality. Rapid diagnosis and treatment are essential to ensure a good patient outcome. Injury resulting from penetrating trauma is usually obvious on presentation. The likelihood of associated intra-abdominal injury is high, and subsequent diagnosis and treatment are usually more straightforward than those for other injuries. Blunt trauma is often associated with other injuries, and diagnosis may not be clear cut and may involve many diagnostic modalities including physical examination, ultrasonography, DPL, CT scanning, and laparotomy. The proportion of injuries occurring from penetrating or blunt trauma differs considerably from center to center and from country to country. For example, in New Zealand, penetrating abdominal injury is considerably less common than blunt trauma, whereas in the United States, many more cases of penetrating trauma are seen and treated. The spleen and liver are the most commonly involved organs after blunt trauma; however, all intra-abdominal organs are at risk of perforation or rupture. Although traffic accidents continue to be a major contributor to blunt abdominal trauma, the pattern of this trauma has changed with the introduction of compulsory seatbelt use. This has given rise to a newer constellation of injuries that include abdominal wall injury, visceral rupture, mesenteric avulsion and laceration, and lumbar vertebral fracture and dislocation. The shoulder harness of the seat belt can cause neck injury, rib fracture, pulmonary contusion, and great vessel rupture or thrombosis. Diagnosis Physical examination remains a useful means to detect pain, tenderness, and guarding in the neurologically intact patient and in those patients with obvious injury and hemodynamic instability. If the patient has an altered level of consciousness or has painful injuries elsewhere, especially to the thorax or pelvis, a physical examination alone is unreliable. In these patients, a more objective means of making a diagnosis is required. Focused abdominal sonography for trauma FAST is a highly accurate technique for the detection of free fluid in the abdomen, but accuracy is operator-dependent. FAST is especially indicated in the hemodynamically unstable patient, but it can also play a role in the hemodynamically stable patient. FAST can be performed rapidly in the ED to assess the peritoneal space for the presence of free fluid. FAST does not depict the site of origin of the fluid, nor does it confirm that the fluid is blood. FAST does not image the retroperitoneum. However, FAST does show the pericardial sac, it helps in assessing for incipient tamponade, and it helps in determining the presence of cardiac mechanical activity. The use of ultrasonography in the emergency setting is expanding and expertise with the technique widespread; in many centers it is an important adjunct in the initial evaluation of the trauma patient. FAST is also gaining a role in the assessment of penetrating abdominal trauma, particularly after low-velocity injuries, such as stab wounds. In the hemodynamically stable patient, free fluid in the presence of penetrating trauma indicates peritoneal penetration and therefore provides a quick means for determining the need for exploratory laparotomy. The absence of free fluid however, does not exclude peritoneal penetration. Therefore, FAST is specific but insensitive in the assessment of penetrating trauma. Diagnostic peritoneal lavage DPL was once a common screening technique used to aid in the diagnosis of hemoperitoneum and ruptured viscus in patients with multisystem trauma. In many centers, it is an important adjunct in the initial evaluation of the trauma patient. With the advent of FAST for the hemodynamically unstable patient, and CT for the stable patient, DPL is now only rarely performed. After the insertion of gastric and bladder catheters, DPL can be performed by using a closed trocar method or by using an open minilaparotomy technique. A catheter is inserted into the peritoneal space, from which aspiration of blood is attempted. If no blood is found, 1 L of warmed isotonic sodium chloride solution (or Ringer lactate) is run into the peritoneal cavity and out. The DPL result is positive when an initial aspiration yields more than 10 mL of fresh blood, when more than 100,000 RBCs/mm3 are observed, or when more than 500 WBCs/mm3 are observed. The results obtained from DPL are nonspecific, and the procedure is considered oversensitive. Only a small volume of free intraperitoneal blood can lead to a positive result; false-positive results can occur from a retroperitoneal leak, which cannot detect contained solid-organ injury but can confound later CT scans by introducing both air and fluid into the peritoneal cavity. This, together with a high incidence of nontherapeutic laparotomy and a move to a more conservative approach to the management of solid-organ injury, has caused this procedure to be redefined in the diagnostic armamentarium. Currently, DPL is used more commonly for patients who are hemodynamically unstable, when an ultrasound to search for free fluid is unavailable. CT scanning of the abdomen This study has become a routine screening test for stable patients with blunt abdominal trauma. A CT scan can depict free intraperitoneal fluid, localize its source, image the retroperitoneum, improve imaging of solid-organ injury, and depict injuries to hollow viscera. New technology is continually leading to improved quality of the images and the scanning time. Current drawbacks to the CT scan are that, in many institutions, the CT suite is not located within the receiving area of the ED, necessitating moving and monitoring the patient in a relatively foreign environment. Preparing and transporting the patient to the CT scan suite takes considerably longer than performing the scan, and patients with acute injuries may require both nonenhanced (of the brain) and contrast-enhanced scans (of the abdomen and/or pelvis). Penetrating abdominal trauma Stab and gunshot wounds account for most patient presentations of penetrating abdominal trauma, with some resulting in obvious peritoneal irritation and requiring immediate exploration. If a uniform policy of laparotomy existed for all penetrating injuries that have the potential to penetrate the abdominal cavity, an unacceptably high rate of negative results would occur. Observation is advocated by some high-volume trauma centers in which designated in-house trauma service staff are available 24 hours a day, 7 days a week to continually reassess patients for changes indicating peritoneal penetration). In other institutions wound exploration, sonography, DPL, and laparoscopy are the techniques most commonly used to determine the need for a laparotomy in a patient who is hemodynamically stable. Trauma to the diaphragm The most commonly injured area of the diaphragm from blunt trauma is the posterolateral left hemidiaphragm, resulting in tears that are 5-10 cm in length. Chest imaging may show loss of clear diaphragmatic air interface, elevation of the hemidiaphragm, obscuration of the hemidiaphragm by abnormal gas shadows, and a nasogastric tube observed in the thorax. Pancreatic injury Isolated pancreatic injury is difficult to diagnose in the absence of other indications for a laparotomy or abdominal CT. Severe blunt trauma injury to the abdomen can compress the pancreas against the vertebral column with sufficient force to rupture or lacerate the pancreatic parenchyma. In such cases, measuring serum amylase seldom is useful, measuring peritoneal amylase from a DPL may or may not be useful, and CT findings may be equivocal. However, CT scans obtained with intravenous and oral contrast enhancement usually demonstrate reduced contrast distribution to the area of injury. If duct transection is suspected, an emergency endoscopic retrograde cholangiopancreatography or laparotomy may be required. Pancreatic debridement, wide drainage, and duct drainage and/or reconstruction are required. Duodenal injury The duodenum is usually injured as a result of direct penetrating trauma or severe abdominal compression (eg, from a seat belt). Diagnosis of such injuries may be difficult: plain abdominal radiographs may show loss of the right psoas shadow or retroperitoneal air, DPL or ultrasonography seldom aid in diagnosis, CT findings (even those obtained by using double contrast agent) remain difficult to interpret in the absence of a grossly obvious duodenal deformity or contrast extravasation. Hence, the diagnosis is usually made at laparotomy performed for nonspecific abdominal findings or for a ruptured solid organ. Genitourinary system injuries Renal injury should be suspected when a patient presents with back or flank contusions or gross hematuria. CT helps in identify 95% of injuries resulting from blunt trauma. Finding a concomitant anterior pelvic fracture (ie, below the urogenital diaphragm) with urethral injuries is most common and is associated with microscopic hematuria. The anterior pelvic fracture occurs most commonly from a force directed to the pubic rami, whereas the posterior pelvic fracture above the urogenital diaphragm often is associated with multisystem pathology. However, even in the absence of gross hematuria, renal artery thrombosis and disruption of the renal pedicle may be present and are most easily diagnosed with a contrast-enhanced CT scan, renal arteriogram, or intravenous pyelogram.
Patients with exsanguinating pelvic trauma present with profound shock that is poorly responsive to even aggressive resuscitation. Pelvic fractures result from considerable force and are often accompanied by other injuries. When assessing and resuscitating such a patient, one must consider the other common sites of hemorrhage. Blood can collect into only 5 places: (1) the floor or dressings by means of external hemorrhage (eg, through the scalp), (2) the chest, (3) the abdomen, (4) the muscles adjacent to long bones, and (5) the retroperitoneum. The mechanism of injury, the presence of posterior pelvic disruption, and the presence of pelvic instability suggest the possibility of major pelvic hemorrhage. This condition usually results from injuries that disrupt the posterior pelvis after the application of an anterior or posterior force that widens the pelvic diameter. This usually manifests itself as an open-book fracture with a sprung symphysis pubis and an open sacroiliac joint. As a result, the internal iliac artery and accompanying veins may be damaged and under those circumstances, can bleed torrentially. Delayed diagnosis and treatment can prove to be rapidly fatal for the patient. A real dilemma that often confronts the trauma team is diagnosing and differentiating intraperitoneal bleeding from retroperitoneal hemorrhage that is associated with a pelvic fracture. In the patient who is unstable, the rapid diagnosis of intraperitoneal hemorrhage can be made most rapidly by using FAST scanning, DPL, or laparotomy. Techniques for the management of exsanguinating pelvic hemorrhage initially may include external compression (pelvic wraps using a sheet), external fixation, angiography with embolization, and, open pelvic packing performed in the context of damage control laparotomy. These patients are often best treated in a room where both surgery and angiography can be performed. Surgical approaches are usually used when a patient with a major pelvic disruption has hypotension and when an intraperitoneal component from another source is suspected. Having treated or ruled out such a source, the surgeon faces an expanding retroperitoneal hematoma. Depending on the circumstances, application of an external fixator or the performance of angiography and embolization might follow. Opening the hematoma at laparotomy destroys the tamponade effect of an intact retroperitoneum and can result in exsanguination. Alternatively, retroperitoneal hematomas may rupture into the peritoneal space, giving rise to a false-positive result on FAST scanning or DPL. Exploration reveals no intraperitoneal injury but discloses a sizable retroperitoneal hematoma and active (usually venous) hemorrhage. The scenario is then identical to the situation described above.
The specific task of the intensivist is to prevent and manage organ dysfunction. Historically, this task began as ventilation for respiratory failure and the management of acid-base disorders by using hemodialysis. Critical care in the new millennium more complex and involves multiple organ systems and increasingly advanced techniques. The educational background of the intensivist varies with the part of the world in which one practices. For example, in the United States, critical care specialists who care for trauma patients usually are surgeons. Not only do these specialists provide surgical care for the trauma victim, they also are responsible for the patient's care in the ICU. In other institutions, the critical care of trauma patients is performed by critical care specialists with a background in anesthesiology or internal medicine, in conjunction with the trauma surgeon. In Australasia, intensive care medicine is a distinct discipline with practitioners attracted from a variety of backgrounds; these practitioners include surgeons, internists, anesthesiologists, and emergency medicine specialists. These practitioners are based in the ICU, but they often have responsibilities to assess and help manage critically ill patients on the wards or in the ED. In New Zealand in particular, intensivists form part of the triaging and treating trauma team, and they are involved in patient care from the moment of presentation. In this role, the intensivists are direct healthcare providers, while simultaneously acting as healthcare brokers. Initially, the intensivists ensure that the patient progresses through the diagnostic and therapeutic protocols in a timely and effective fashion. Later, in the ICU, intensivists ensure that appropriate expertise is available to allow the patient to receive optimal treatment for multiorgan support and management.
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