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This chapter discusses critical care medicine and the management of critically ill patients. It focuses on multiple organ dysfunction syndrome (MODS), which involves dysfunction of many different organ systems at the same time. MODS can be caused by sepsis or trauma, and it carries a high risk of mortality. The lungs and cardiovascular system often fail first, leading to the failure of other organs. Treatment for MODS involves organ support and maintaining tissue perfusion. The goal is to address the underlying cause of infection and restore blood flow. Intravenous fluid therapy and medications are used to maintain blood pressure. Antimicrobial therapy should be started as soon as infection is suspected. The management of MODS also includes monitoring and maintaining central venous pressure, mean arterial pressure, and tissue oxygenation. Cultures and imaging studies are done to identify the source of infection. Antimicrobial therapy should be adjusted based on culture results and pati Chapter 1 Critical Care Medicine. This chapter is concerned with the management of critically ill patients. Patients can be critically ill from an acute illness, the exacerbation of a chronic illness, or from an acute traumatic injury. Many of these patients have damage to many organ systems requiring intensive treatment and support of organ or body systems. Critically ill patients are often cared for in the intensive care unit with one-to-one nursing and ventilator support. They are on several medications and receive treatment from many types of health professionals. Multiple Organ Dysfunction Syndrome. Multiple organ dysfunction syndrome, or MODS, involves having dysfunction of many different organ systems at the same time. There can be several causes of multiple organ system dysfunction, the most common of which is sepsis. MODS carries a high risk of mortality. At least two organ systems must be dysfunctional to be classified as multiple organ system dysfunction. These include the renal system, the liver, the heart, the respiratory system, the blood, and neurologic system. Signs and symptoms of MODS can involve many of the organ systems. There may be respiratory problems with difficulty in airway gas exchange. There can be hypoxemia from poor gas exchange in the lungs. The kidneys can also be involved. There can be poor urine output even when there is adequate fluid volume in the extracellular fluid space. Dialysis is sometimes necessary to keep the kidneys functioning normally. The heart can have abnormalities. It can suffer hypoxic injury from low oxygen levels in the blood and can begin to fail. The liver can fail, resulting in an excess of bilirubin. Many patients suffer from an altered state of consciousness, either from trauma or from metabolic toxicity. There can be blood disorders, the most common of which is thrombocytopenia or low platelet count. MODS is usually a secondary diagnosis with the primary cause being an insult to one or more organ systems. There is an inflammatory reaction from an infectious agent or from a severe organ system disease. As mentioned, the most common cause of MODS is sepsis, which results in a high degree of inflammation. Trauma can cause MODS by damaging tissues and muscles, causing toxicity, or having metabolic problems. Prolonged shock from sepsis or trauma can injure organs, resulting in MODS. Cardiopulmonary failure involves the failure of both the heart and lungs, which often fail together. Often, the beginning of MODS involves the failure of the heart or lungs, resulting in hypoxia and difficulties in many organ systems. A lack of proper oxygenation to the heart causes the heart muscle to fail, which impairs blood flow and oxygenation in the tissues. When the end organs are not adequately oxygenated, this results in diseases such as kidney failure and liver failure. Fluid can leak out of the blood vessels when the heart fails to pump blood adequately to the coronary arteries. This causes fluid to build up in the lungs, resulting in pulmonary edema. This restricts the function of the lungs and worsens oxygenation, leading to even worsened failure of end organs. Toxins build up that cannot be gotten rid of by the kidneys or liver. This worsens the damage to the end organs in a negative feedback loop, where there is ongoing worsening of oxygenation, blood flow, and end organ damage. Multiple organ dysfunction is difficult to treat with any type of medication. Treatment is directed at organ support and hemostasis of the respiratory system, cardiac system, and blood. The aim of treatment of MODS is to keep as much oxygenation to the tissues as possible in the face of decreased gas exchange and poor tissue perfusion. Many people need parenteral nutrition to be started as early as possible in the course of their disease to keep nutrients flowing to the end organs. Adequate nutrition decreases the risk of infectious complications and prevents malnutrition. Even with maximal treatment, the mortality rate is extremely high in patients with MODS. The more organ systems that are failing, the higher is the rate of death. Even with modern medical technologies, the rate of death in MODS continues to be high as there is little intervention that can be done besides providing the patient with maximal supportive care and nutrition. Sepsis is the number one cause of MODS and carries a high rate of death and subsequent disability. Generally, the lungs fail first, followed by the cardiovascular system. This results in the failure of other body systems that don't get adequate tissue perfusion. The goal is to keep the cardiovascular system going adequately so that the other end organs get properly perfused. If infection is the cause of MODS, the first goal is to find the source of the infection and treat it as soon as possible so the damage to the cardiovascular system can be minimized. The treatment of MODS secondary to sepsis involves three goals. The first is to restore blood flow when the blood pressure drops in the infectious process. Hypoxia, hypotension, and poor tissue perfusion need to be addressed simultaneously. The cause of the infection needs to be determined and adequate oxygenation needs to be re-established. If surgery is necessary to rid the patient's infection, this must be done as soon as the patient is hemodynamically stable. Finally, the third goal is to maintain homeostasis and functioning of the organ systems so that toxins don't build up and the endocrine system is maintained. Septic shock is recognized by the following characteristics. The patient generally has mental system changes consistent with brain hypoxia and toxin buildup. The patient often hyperventilates and may have either a low body temperature or a high body temperature. There may be a reduced white blood cell count or an extremely high white blood cell count. A source of infection may be obvious or difficult to identify, depending on the infection. These patients need urgent cardiovascular resuscitation with high volumes of intravenous fluid given. Vasoactive drugs may be necessary to bring the blood pressure into normal range. Many patients need endotracheal intubation and ventilator support as they have inadequate ventilation without ventilator support. Empiric intravenous antimicrobial medications must be given as soon as infection is suspected, with definitive antimicrobial medication given when cultures of the blood or infectious source are completed. Resuscitation begins with intravenous fluid therapy and medications that are directed at maintaining the blood pressure. Norepinephrine is the drug of choice for restoring blood pressure. However, if this fails, dopamine may be given. Dobutamine is another drug often used for hemodynamic stabilization. Epinephrine is not recommended in septic shock, but can be used in other types of shock, such as cardiogenic shock. Patients in shock quickly develop lactic acidosis and secondary metabolic acidosis. This can be difficult to treat as giving bicarbonate to correct the acidemia can worsen the acidosis happening inside the cells. Correcting acidemia in patients who have shock has not been found to be effective in improving homeostasis of the cardiovascular system. It is, however, recommended in patients who have an arterial pH level less than 7.20, or if the serum bicarbonate level is less than 9 millimoles per liter. The main damage from septic shock is the development of toxins and the increase in inflammation in the body secondary to widespread infection. Even though inflammation is felt to be the cause of much of the end-organ damage, correcting inflammation by giving the patient high-dose corticosteroids in shock has not been found to be particularly effective. Tight glycemic control is recommended in shock patients so that the blood glucose level is never higher than 150 milligrams per deciliter. The management of MODS patients begins with resuscitation and normalization of the blood pressure to minimize hypoperfusion of the tissues. The central venous pressure should be monitored and maintained, so the central venous pressure is between 8 and 12 millimeters of mercury at all times. The mean arterial pressure must be kept above 65 millimeters of mercury and the output should be higher than 0.5 milliliters per kilogram per hour. The oxygenation of the superior vena cava must be at least 65 to 70 percent. If the patient has elevated lactic acid levels, this must be brought down as fast as possible. Cultures of suspicious areas need to be done as well as blood pressure monitoring. Antimicrobial therapy must be started even when cultures are pending and an obvious source has not yet been identified. At least two sets of blood cultures should be obtained before starting antimicrobial therapy. Imaging studies need to be done to try and identify the source of the infection. IV antibiotics need to be given within the first hour that septic shock is identified to attempt to reverse the cause of the shock. One or more intravenous drugs should be used to cover for any bacterial or fungal agent that is causing the infection. There must be adequate tissue perfusion for the antimicrobials to get to the source of the infection. The choice of antimicrobial therapy must be continually re-evaluated as cultures come back or if the patient doesn't seem to be responding to the current antimicrobial treatment. Patients with severe neutropenia need to be on multiple antimicrobials for at least 7 to 10 days. Longer courses of antimicrobials need to be given if the patient slowly responds to the therapy or if there are documented cases of staphylococcal aureus infections, viral infections, or fungal infections. If the patient is neutropenic, the course of antimicrobial therapy needs to be longer. If a virus is the cause of the sepsis, antiviral therapy needs to be started. If the sepsis appears to be purely an inflammatory problem and no infectious source is identified, antimicrobials do not have to be started. In the absence of ongoing infection, there needs to be an attempt at reducing the risk of nosocomial infections. There needs to be selective oral and digestive decontamination and efforts made to reduce ventilator-associated pneumonia, which involves adequate oxygenation and aseptic technique whenever possible. Oral chlorhexidine gluconate can be given to decontaminate the mouth, reducing the chance of oral contamination to the lungs in septic patients. Crystalloids should be used primarily in the first stages of sepsis resuscitation. Experts in sepsis treatment do not recommend using hydroxyethyl starches. Albumin can be given along with crystalloids when resuscitating the shock patient, especially when large volumes of crystalloids need to be given in the resuscitation process. The choice of antibiotic is based on what the potential source of the infection is. The antibiotic must cover for gram-positive organisms, gram-negative organisms, and anaerobic bacteria. The doses of antibiotic therapy need to be high enough to be bactericidal as the patient's natural immune defenses can be expected to be low. It is better to give a high dose of a few or just one antibiotic than it is to give lower doses of several antibiotics. Anaerobic coverage is a priority when abdominal or perineal infections are suspected. If the patient is severely neutropenic, coverage against pseudomonas must be given. Burn patients need this type of coverage as well. If the patient is immunocompetent, then just one high-dose antibiotic needs to be given. A third-generation cephalosporin is adequate in these types of patients. In those types of patients suspected of being immunosuppressed, two broad-spectrum antibiotics should be given that overlap in coverage of microorganisms. There is no selection of antibiotic therapy that has been found to be superior to any other antibiotic selection. When fluid resuscitation is inadequate to restore blood pressure, then vasopressor medication must be used. Dopamine, norepinephrine, and phenylephrine have been successfully used. These drugs are able to maintain a reasonable blood pressure despite life-threatening sepsis and hypotension. The blood pressure must be kept high enough to perfuse the kidneys and abdominal organs. The first choice of vasopressor in sepsis is norepinephrine or dopamine. Epinephrine can be used if these fail to restore a normal blood pressure. Norepinephrine is started first, followed by vasopressin, which can help reduce the dose of dopamine or norepinephrine being used. Dopamine can precipitate tachyarrhythmias, so it should be used judiciously in patients with cardiovascular disease. Phenylephrine as a vasopressor is not recommended in treating shock patients except when the use of norepinephrine causes tachyarrhythmias or when dopamine and vasopressin fail to maintain the patient's blood pressure. Epinephrine can increase the mean arterial pressure because it increases the stroke volume of the heart, increases heart rate, increases systemic vascular resistance, and increases the cardiac index. It does, however, increase the lactic acid concentrations in the tissues, so it is only recommended if other vasopressive medications are unsuccessful in treating the hypotension. Besides increasing lactic acid concentrations, epinephrine can also worsen cardiac ischemia and can cause arrhythmias. It can decrease the flow of blood to the splanchnic organs. Dopamine can be used. It has the benefit of causing vasodilation of the kidney arteries, mesenteric arteries, and coronary arteries. It can increase the contractility of the heart and will increase the heart rate. Blood pressure will rise and there will be an increase in vasoconstriction. It is not as effective as norepinephrine in treating hypotension in septic shock patients. The main negative effect of dopamine is tachycardia and pulmonary shunting, which decreases oxygenation of the splanchnic organs. Phenylephrine is a selective alpha-1 adrenergic receptor agonist used in anesthesia settings to increase the patient's blood pressure. It has also been found to be effective in increasing the blood pressure in patients with septic shock. The downside of phenylephrine is that it increases oxygen consumption and may decrease the cardiac output. It is a good choice when the patient is at high risk for tachyarrhythmias. Most septic shock patients respond well to an increase in fluid volume alone so that the use of vasopressors is not always needed. The goal is to maintain oxygen delivery to the tissues using volume resuscitation first followed by vasopressors if volume resuscitation doesn't provide good tissue perfusion. Besides dopamine, norepinephrine, phenylephrine, and epinephrine, dobutamine can be used to maximize tissue perfusion. Corticosteroids are often used in the treatment of shock even though it has not been found to be effective in reducing shock, improving mortality, or preventing infection. The routine use of corticosteroids in shock patients isn't recommended at this time. Patients with refractory shock can be tried on intravenous hydrocortisone for up to a week or until vasopressors are no longer necessary to keep the patient's blood pressure in the normal range. The initial evaluation and management of a critically injured patient suffering from multiple trauma can be challenging. In the past few decades, there has been an improvement in the understanding of what goes on when a patient is injured and multiple organ systems are involved so that the mortality rate has declined dramatically. Deaths from trauma can be immediate, early, or late. Patients who die immediately generally have irreversible injury to the great vessels, heart, or brain. The patient generally dies at the scene of the trauma and is never treated in the emergency department. In some cases, these deaths can be prevented by maximizing resuscitative efforts at the scene. Early deaths from trauma occur within minutes to several hours following the injury. These patients usually make it to the emergency department and suffer death from overwhelming hemorrhage or cardiovascular collapse that is unresponsive to resuscitative efforts. Late deaths from trauma happen days to weeks after the injury. Adequate critical care is necessary to avert these types of deaths. Early deaths secondary to trauma stem from failure to oxygenate the vital organs. From severe trauma to the nervous system, infectious diseases, or a combination of these. Things like inadequate oxygenation, poor ventilation, circulatory collapse, and lack of perfusion of end organs contribute to the patient's demise. In cases of severe CNS trauma, signals to the heart and lungs are impaired and the patient cannot oxygenate or perfuse their organs. Early trauma deaths depend on the patient's age, gender, body habitus, or the environmental conditions surrounding the trauma. Patients who suffer trauma in rural areas have delayed access to trauma care and are at a greater risk of early trauma deaths. The development of the Advanced Trauma Life Support System has improved mortality because rural providers and ambulance personnel have begun to be trained using approaches developed by ATLS. Using ATLS protocols consistently has provided for the best resuscitation of patients with life-threatening injuries. The evaluation and treatment of trauma patients comes down to quickly finding those injuries that are life-threatening, adequately supporting the cardiovascular system, and arranging for definitive therapy, which usually involves rapid transfer to a trauma center. Triage The main objective of triage is to put patients in categories according to their chance of survival. The vital signs are assessed along with the patient's mechanism of injury, age, and suspected underlying medical conditions. Evidence that a faster workup is necessary include having multiple injuries, being extremely young or quite elderly, having severe neurological trauma, having an instability of the vital signs, having pre-existing cardiac disease, or having lung disease. The primary survey is performed first to identify those things that are life-threatening. Obstructed airway takes precedence over impaired circulation and things like the necessity of amputation or other organ injury. If possible, caregivers need to assess all body symptoms at the same time while simultaneously correcting those things that are correctable. By evaluating and treating at the same time, patients with multiple traumatic injuries can be treated and stabilized faster. The need for a resuscitation team is labor-intensive but is necessary in the trauma setting and in cases where there are mass casualties. When many victims are in need of care, the triage process allows for the maximal amount of care to be given to those patients who are expected to survive their injuries but that need intervention. In some cases, the most severely injured patients are not treated because they are not expected to survive, even with maximal resuscitation. The resuscitation team needs to be organized as soon as it is deemed necessary to treat one or more traumatized patients. Leadership roles need to be established early and equipment needs to be operable. In larger hospitals, surgeons need to be notified and available to correct any surgically correctable traumatic injuries. The team leader should be a physician skilled in the management of trauma patients. Other doctors or providers are designated to be responsible for the airway management, blood pressure control, and the secondary survey of the patient. If procedures need to be done, a health care provider skilled in that area needs to be available to provide the service. Nurses must be available for the continual monitoring of the vital signs, intravenous access, and the attainment of blood samples. If possible, respiratory therapists need to be on hand for airway management and x-ray services need to be available for radiologic studies. Neurosurgeons and orthopedic surgeons need to be contacted immediately as soon as it becomes evident they are needed. If there is severe CNS trauma, a neurosurgeon must be readily available to provide emergency neurosurgical intervention for patients with CNS trauma. The first step in trauma care is the performance of a primary survey. It involves the evaluation of the airway, breathing, circulation, disability, and environmental exposure. The first priority is airway. This is assessed by determining the availability of environmental air to enter lungs that are unobstructed. Obstruction of the airway can be due to direct injury to the pharynx or larynx, foreign bodies inside the airway, edema, or an inability of the individual to protect their airway because of a decreased level of consciousness. Treatment of airway disturbances can be done by removing excretions using suction or by intubating the patient. If facial trauma is present, the patient can have a surgical airway placed. The next step is to evaluate the patient's ability to spontaneously ventilate and oxygenate for themselves. Findings of impaired ventilation include the absence of spontaneous breathing, absent or asymmetric breath sounds, shortness of breath, or dullness of the chest wall during chest percussion. There can be disturbances of the chest wall suggestive of chest wall injury, a sucking chest wound, or flail chest. These can be managed by treating the hemothorax, pneumothorax, tension pneumothorax, or sucking chest wound with an emergency thoracostomy and chest tube placement. If the patient has flail chest, they need mechanical ventilation, which is often necessary for other injuries that are causing the ventilation difficulty. The circulation is next assessed by looking for evidence of low blood volume, cardiac tamponade, and external sources of bleeding. The neck veins need to be evaluated for collapse or distention, and there needs to be an assessment of the heart tones. The hypovolemia needs to be treated by placing two large-bore peripheral intravenous catheters containing Ringer's lactate and giving a large fluid bolus. Upper extremity catheters are preferred over lower extremity catheters. If there is cardiac tamponade, pericardiocentesis is warranted. This needs to be followed by immediate surgery to find and repair the cause of bleeding. External bleeding can be controlled by direct pressure or emergent surgery. The patient's estimated level of disability can be assessed by doing an initial gross mental status examination and a motor examination. Find out if there has been a serious head injury or spinal cord injury. Use the Glasgow Coma Scale to assess the patient's level of consciousness. The pupils need to be looked at for size, reactivity to light, and symmetry. Spinal cord injury needs to be assessed by observing motor movement. Pupillary findings or hemiplegia suggests possible upcoming herniation of the cerebrum through the tentoria incisora because of an expanding mass in the brain or because of cerebral edema. If these findings are seen, the patient needs emergency management for increased intracranial pressure. Treatment includes intravenous mannitol, hypertonic saline, sedatives, and muscle relaxants. This needs to be done after an adequate airway is established. Emergency neurosurgical intervention is necessary. If there is no decreased level of consciousness and the presence of paraplegia or quadriplegia, there is probably a spinal cord injury. The possibility of a spinal cord injury necessitates full spinal immobilization. If respiratory efforts are weak because of a high cervical spinal cord injury, endotracheal intubation is necessary. The last step in the primary survey includes evaluating the patient's exposure to a harmful environment and control of the environment. The patient's clothes need to be removed and a thorough physical examination needs to be undertaken. Treatment for hypothermia needs to be undertaken as removing their clothing can worsen this problem. Warm blankets can be provided along with warming of the intravenous fluids. Heat lamps may be used, and if available, warmed air-circulating blankets. There can be diagnostic intervention and monitoring along with the primary survey. The electrocardiogram leads can be placed, and pulse oximetry can be implemented. Monitors can provide information crucial to the resuscitation process. They need gastric intubation to remove excess stomach gas and fluids. If possible, a urinary catheter can be placed, which can allow for evaluation of the patient's fluid status. This can't be done in situations of a urethral injury. A retrograde pyelogram should be done if a urethral injury is suspected before a catheter can be placed. While the primary survey is going on, the provider is simultaneously making diagnoses and doing interventional procedures until the patient's condition is more stable. During this time, the patient has ongoing monitoring of the vital signs, protection of the airway, oxygenation, intravenous fluid resuscitation, and the administration of blood products. Patients who have multiple injuries may need several liters of crystalloid fluids over the first 24 hours to maintain an adequate blood pressure, tissue perfusion, and end-organ perfusion. The urine output needs to be adequate during this time. Blood is given for low blood volume that isn't responsive to intravenous crystalloids. If blood loss isn't controlled by direct pressure and transfusion, surgery or diagnostic imagery needs to be done to evaluate and treat the source of the bleeding. The endpoint of the resuscitative process includes normal vital signs, lack of ongoing blood loss, normal urine output, and lack of evidence of end-organ damage. Things like base deficits found in arterial blood gases and blood lactate levels may aid in the treatment of severely injured patients. The patient with abnormal vital signs suggesting low blood pressure is at a high risk for blood loss of at least 30 to 40 percent. After the primary survey is finished and after resuscitation, a head-to-toe evaluation of the patient's body is performed. The vital signs are continually reviewed, and the provider needs to repeat the primary survey to assess the patient's response to the resuscitative process. The patient's history is looked at, as well as any reports from pre-hospital personnel. If family members or witnesses are available, they can enhance the patient's history. Find out if the patient has any pre-existing medical conditions and if they are on any medications. Find out their allergies, tetanus status, time of last meal, and any events related to the injury. The secondary survey is done while paying attention to the mechanism of injury, the likelihood of a coexisting cold or heat injury, and the patient's overall physical status. Each body area needs to be evaluated for evidence of injury, including the abdominal organs and bones. A full neurological assessment needs to be undertaken as part of this survey. This should include a complete cranial nerve evaluation. The neck should be evaluated for evidence of airway injury or damage to the great vessels. The posterior aspect of the spine should be evaluated for cervical injury or tenderness to the cervical spine. Full spinal precautions need to be undertaken if there is blunt trauma and an unknown mechanism of injury. The chest should be palpated for injury to the chest wall. Crepitation, tenderness, or instability of the chest wall suggests a chest injury. The patient's heart and lungs need to be listened to. There should be an evaluation for penetrating trauma to the chest. Chest tubes need to be evaluated to make sure they are working, and a portable chest X-ray is necessary to assess for continued pneumothorax, mediastinal trauma, bony injuries, and to assess the placement of endotracheal tubes, gastric tubes, and chest tubes. The abdomen needs to be assessed for distension or other evidence suggestive of an intraabdominal injury or intraabdominal bleeding. If there is penetrating trauma, a local evaluation should be undertaken to see if the abdominal muscles were penetrated. High-velocity penetrating trauma needs surgical evaluation and intervention. The pelvis needs to be assessed for pelvic fractures. An AP pelvis film can be done to look for fracture. If a pelvic fracture is suspected, the pelvis should not be manipulated, as this can worsen the bleeding. Perineal evaluation needs to be undertaken, looking for bleeding, gross blood in the vaginal canal, blood in the rectum, or urethral blood. If there is no suspicion of urethral trauma, a Foley catheter can be placed. If there is a suspicion of spinal cord injury, the anal sphincter tone should be assessed during this part of the evaluation. An extremity evaluation should happen next. If long bones are fractured, these require stabilization. Plane films of the bones should be done to identify deformities, tenderness, or bone instability. Temporary splints need to be placed before discharging the patient from the emergency room to another part of the hospital. If there is extremity evidence of vascular compromise, this should be treated, as ischemic injury to the extremities can result in irreversible damage to these areas. The neurological examination is usually done during the secondary survey, but now is the time to formally assess the patient's spine for injuries. The entire spine needs to be palpated for bony abnormalities, tenderness, or deformity. A detailed evaluation of the back should be undertaken to evaluate for bruising or penetrating injuries. X-ray imaging can provide critical data that are used to guide the initial evaluation. X-rays should be done in a particular order so that life-threatening injuries are identified and treated first, with lesser injuries identified and treated last. The patient needs to be fully resuscitated before being transferred to radiology for secondary X-rays. The most important X-ray in trauma patients is the AP chest X-ray. It can be performed in the resuscitation phase and can help identify lung contusions, pneumothorax, or hemothorax. This X-ray can also identify positioning of the endotracheal tube, chest tubes, and gastric tubes. An AP portable pelvis film can be taken in the resuscitative phase, which can help identify life-threatening sources of bleeding. If the pelvis is bleeding, angiographic embolization or external fixation needs to be undertaken. After X-rays, a focused abdominal sonogram for trauma, or FAST, needs to be undertaken. This should be done by a trauma clinician who is skilled in this technique. The ultrasound does not take very much time and can identify multiple things, including pneumothorax, hemothorax, pericardial effusion, and free fluid in the peritoneal cavity. This is the fastest and most effective way of evaluating the trauma patient for chest and abdominal injuries. It is usually done in major trauma centers as it takes a lot of skill to do this examination. The CT scan can provide definitive evidence of injuries. It can evaluate the patient for abdominal, pelvic, chest, cervical spine, and cranial injuries. Overuse of the CT scan can be harmful if the patient needs emergency surgery, as this can delay the surgery and may not be helpful in treating the patient. If the patient is hypotensive and has a major abdominal injury, they need to have emergency surgery before undertaking a CT scan. When time provides, a CT scan of the head should be done to identify any intracranial injuries that need assessment by the neurosurgeon. The CT scan should be done without intravenous contrast and should be done prior to doing a contrast CT study of the pelvis and abdomen. Scanning of the cervical spine can be done at the same time as the head CT. A CT scan of the chest can be done to evaluate the patient for any mediastinal injuries. CT scanning can evaluate the patient for aortic or other great vessel trauma and is superior to doing angiographic studies of these organs. It is also a more sensitive test for evaluation of rib fractures, pneumothorax, hydrothorax and pulmonary contusion when compared to the chest X-ray. CT scans of the pelvis, head, abdomen or chest are enough to guide the surgeons as to which areas of the body need to be treated surgically. CT scans of the pelvis and abdomen are usually done together using oral and intravenous contrast. Abdominal and pelvic organ damage can be identified along with retroperitoneal and pelvic injuries. This eliminates the need for angiographic study of these areas. However, angiographic interventions may still be necessary. CT scanning is a good replacement for plain radiographs in evaluating patients with spinal trauma. While CT scanning of the spine is being done, there can be simultaneous evaluation of the chest, pelvis and abdomen. If these studies aren't done by the emergency room staff, they are often done by the consulting orthopedist or neurosurgeon. If CT scanning is unavailable, plain films of the spine may be helpful. If the patient is at low risk for spinal injury, this evaluation can be undertaken at a later time. If there is an urgent need to rule out a cervical spine injury, a portable x-ray of the lateral cervical spine can be undertaken in the emergency department during resuscitation. Eventually, a full spinal series needs to take place to evaluate the entire spine. If a cervical fracture is found, there is a 10% chance that the patient has another spinal injury. Magnetic resonance imagery can be done to rule out injuries to the ligaments and muscles around the spine. Nerve root injury can be found on an MRI scan. Angiography can be both a diagnostic test and a therapeutic test. The most common reason why an angiography is ordered in the emergency department is to identify and control bleeding from an arterial source in blood vessels supplying the pelvis or retroperitoneum. Angiographic embolization is the preferred method of treating these types of hemorrhages and helps avoid surgery to treat these things. Angiography can be done after a CT scan with contrast reveals a major bleed in the abdomen or pelvis. The most important lab test to do in the early stages of trauma management is the type and cross-match, which is usually available in 20 minutes. Arterial blood gases can also be done in this period. However, continuous pulse oximetry may be just as valuable and less invasive. A baseline hemoglobin can be done but may not reflect a major hemorrhage in the early stages. This may need to be repeated after fluid resuscitation to fully evaluate the patient for hemorrhaging. Urine drug screens for illicit drugs and an alcohol screen are often done at major trauma centers to see if these things are interfering with the resuscitation process. Blood alcohol and glucose testing can help identify possibly correctable reasons for a low level of consciousness. Assessments of coagulation, electrolytes, and cell counts are not very useful in trauma patients. Key takeaways The most common cause of multiple organ dysfunction syndrome is bacterial sepsis. Patients decompensate because of poor oxygenation that leads to cardiac dysfunction and poor end-organ perfusion. Resuscitation with fluids is the treatment of choice in sepsis. However, vasopressors and albumin can be used to restore volume. Early empiric antibiotic therapy can improve outcome in multiple organ dysfunction syndrome. Trauma patients need to have their airway, breathing, circulation, nervous system, and environment evaluated first. Patients can die immediately, early in the course of trauma, and late in the course. After the primary and secondary surveys, imaging can take place to further evaluate the head, cervical spine, abdomen, and pelvis. Simultaneous examination and treatment offer the best chance of survival. Trauma patients often need care at a trauma center, as these can provide the services a trauma patient needs for definitive care. Quiz Number 1 A patient is seen on the medical ward with new onset hypotension, low body temperature, and changes in mentation. How do you further evaluate this patient? A. Obtain a CT scan of the head to rule out intracranial pathology. B. Obtain a bedside radiograph of the chest to rule out pneumonia. C. Send the patient to the intensive care unit and begin a thorough evaluation for sepsis. D. Start IV antibiotics and look for a source of infection. Answer D. This patient is presenting with all the signs of septic shock. They need intensive care treatment and a thorough workup for sepsis that can only be done in the intensive care unit. Number 2 You are evaluating a patient for sepsis who is otherwise immunocompetent. Blood cultures are obtained as are cultures of suspected infected areas. How do you further treat the patient? A. Start them on at least two bactericidal antibiotics while awaiting culture. B. As the patient is immunocompetent, you can await the culture results before starting the patient on an appropriate antibiotic. C. Start the patient on a third-generation cephalosporin and await the results of the culture. D. Start the patient on an intravenous aminoglycoside and await the results of the culture. Answer C. An immunocompetent patient with sepsis can be placed on a single-agent course of third-generation cephalosporin while awaiting the results of the culture. An aminoglycoside doesn't provide adequate coverage and the patient doesn't need more than one antibiotic. Antibiotic therapy should start before cultures return. Number 3. The patient is being treated for sepsis and has not had normal blood pressure readings after fluid resuscitation. How do you respond next? A. Give the patient intravenous phenylephrine. B. Give the patient intravenous dopamine. C. Give the patient intravenous albumin. D. Give the patient intravenous norepinephrine. Answer D. The initial treatment of choice if volume resuscitation doesn't work is to start a vasopressor. The vasopressor that should be tried first is norepinephrine with the other choices being used only if norepinephrine fails or gives adverse side effects. Intravenous albumin will not restore the blood pressure. Number 4. You are caring for a patient with multiple end organ failure from serious burns. What organism should you consider if the patient is suspected of having sepsis? A. Pseudomonas. B. Klebsiella. C. Staphylococcus. D. Streptococcus. Answer A. The patient is at a high risk of sepsis secondary to pseudomonas because of burns. This patient needs an antimicrobial agent that covers for this in cases of sepsis. Number 5. You are called to the scene of a motor vehicle accident with one victim. The victim was seat belted and was involved in a high velocity single car accident. The victim is found pulseless with no cardiac activity and no evidence of external trauma. What injury has the patient likely sustained? A. Blunt abdominal trauma. B. Head injury. C. Injury to the aorta. D. Cervical spine injury. Answer C. Patients who die at the scene without evidence of external trauma have generally died from cardiac trauma or trauma to the great vessels. There is no evidence of head trauma as the patient was seat belted. Number 6. What is a common cause of late deaths in trauma patients? A. Hemorrhage of the pelvis. B. Pneumonia. C. Cervical spine injury. D. Open orthopedic injury. Answer B. Most late deaths from trauma are secondary to an infectious process such as pneumonia and not from an orthopedic injury or hemorrhage. Number 7. You are evaluating a trauma patient with an intact airway and normal ventilation who is found to be hypotensive. In managing this, what do you do? A. Give typed and cross-matched blood as soon as it is available. B. Place two IVs in two peripheral veins and give Ringer's lactate solution until the blood pressure normalizes. C. Give IV fluids with albumin to diminish the chance of cerebral edema. D. Place a central line and give IV normal saline until the central venous pressure is normal. Answer B. Peripheral lines should be placed and Ringer's lactate solution should be given. Blood transfusions take too long and albumin is unnecessary in the early stages of resuscitation. A central line would take too long and is unnecessary unless a peripheral IV cannot be placed. Number 8. What is the advantage of the ATLS system? A. It helps get trauma patients to a trauma center faster. B. It has standardized trauma care for individuals in all parts of the country. C. It teaches advanced interventional techniques to ambulance personnel. D. It allows rural victims to have a better chance of survival. Answer B. The main advantage of the ATLS system is that it has standardized trauma care throughout the country so that victims from just about anywhere can receive adequate resuscitative efforts. It does indirectly help rural patients have a better chance of survival. Number 9. What is the main purpose of doing angiography in a trauma patient? A. It is the only way that arterial bleeding can be diagnosed. B. It is a fast way to identify bleeding sources. C. It can be used along with arterial embolization to control severe bleeding. D. It can confirm findings seen on an MRI evaluation. Answer C. Angiography can be done to identify bleeding sources, but it is not very fast and is mainly used when anticipating arterial embolization to control severe bleeding. Number 10. Which imaging test is usually done first in trauma patients? A. CT scan of the head. B. CT scan of the cervical spine. C. AP x-ray of the cervical spine. D. PA x-ray of the chest. Answer D. The first imaging test usually done in cases of trauma involve a PA x-ray of the chest to look for pneumothorax, hemothorax, and placement of tubes and lines.
