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TRAUMA CARE Table 3: Acidosis: Respiratory & Metabolic RESPIRATORY METABOLIC PROBLEM PCO2 EXAMPLES OF CAUSES RESPONSE Hypoventilation, poor exchange of gasses (COPD, infection) Kidney absorb NaHCO3 excrete H+ ; Not related to PCO2 Diabetic acidosis, lactic acidosis, high fat intake, ingested substances Hyperventilation, kidney reabsorb NaHCO3 , excrete H+ Alkalosis: Respiratory & Metabolic RESPIRATORY PROBLEM EXAMPLES OF CAUSES RESPONSE ¯ PCO2 Hyperventilation from a variety of causes Kidney removes NaHCO3 reabsorbs H+ remove carbon dioxide through effective breathing (Table 3).18–23 Metabolic acidosis can be caused by several different pathways.18–23 In meta- bolic acidosis, the lungs and kidneys try to compensate. If the acidosis continues, the body's pH buffering system can be overwhelmed. This can result in lowered blood pH, triggering stimulation of the central nervous system, resulting in tachypnea. Tachypnea can increase the amount of carbon dioxide exhaled. The renal system may compensate by excreting more acid in the urine. Both mechanisms can be overwhelmed if the body continues to produce too much acid, leading to severe acidosis and eventually, if not reversed, death.18–23 Many symptoms of acidosis can be similar to those of underlying diseases or medical conditions. Symptoms can include tachypnea, tachycardia, brady- cardia, dysrhythmias, vasodilation and hypotension, ; METABOLIC Not related to PCO2 Vomiting, excessive ingestion of alkali (e.g. toothpaste) Hypoventilation, kidney removes NaHCO3 , reabsorb H+ weakness.2–4,18–23 Prehospital treatment of acidosis should focus on managing the suspected cause (e.g., the injury) and contributing underlying diseases. In the setting of multisystem trauma, management of hypoxia and hypoperfusion is impor- tant. Providers should ensure that the patient's airway is patent and oxygen is administered. Recalling that hypovo- lemia and hypoperfusion can lead or contribute to acidosis, give intravenous fluids per local protocol. In the prehos- pital setting, administering medications such as sodium bicarbonate to overcome acidosis is rarely indicated.2–4,18–23 Coagulopathies Coagulopathies, or bleeding disor- altered mental status, nausea, vomiting and fatigue. While it's not always possible to differen- tiate the symptoms of respiratory and metabolic acidosis in the field, respira- tory acidosis may include headaches, confusion and bradypnea. Metabolic acidosis can include tinnitus (ringing in the ears), vertigo, blindness, blurred vision, visual changes, photophobia (fear of light), tachycardia, palpitations, chest pains, hyperventilation, dyspnea, headache, altered mentation, nausea, vomiting, abdominal pain, diarrhea, polyphagia and generalized muscle 48 FEBRUARY 2012 | EMSWORLD.com ders, can result from a number of different events, including excessive fluid dilution, metabolic events (e.g., acidosis), hypo- thermia and disseminated intravascular coagulation (DIC). When a healthy person is injured, proteins in the blood become activated and travel to the site of injury to assist with clotting. In normal situations the clotting factors are replaced as they are consumed. In DIC widespread thrombus formation occurs, along with depletion of platelets and clotting factors. This leads to clotting complications, clot break- downs and an inflammatory response by the body. As a result, small blood clots begin to form in the blood vessels; these can occlude vessels and cut off blood supply to organs. As this cycle continues, clotting factors are consumed, and simul- taneous hemorrhage and thrombosis can occur. The systemic activation of the coagulation process leads to deple- tion of coagulation factors as clots are formed and broken down.6–8,24,25 Symptoms associated with DIC include hemorrhage, renal complica- tions, hepatic dysfunction, respiratory compromise, hypotension, tachycardia, CNS dysfunction, epistaxis, gingival bleeding, mucosal bleeding and fever. Skin abnormalities can include pete- chiae (small red or purple spots on the body), jaundice (yellowish pigmentation of the skin indicating liver dysfunction) and purpura (red or purple discolorations on the skin that do not blanch when pres- sure is applied). Acral cyanosis (persis- tent blue or cyanotic discoloration of the extremities), skin necrosis on the lower limbs, gangrene, wound bleeding and deep subcutaneous hematomas may occur.2–4,24–25 Prehospital treatment options for coagulopathies are limited and tend to be supportive. Providers should focus on securing the patient's ABCs, administering supplemental oxygen, managing external hemorrhage with direct pressure, wound care, maintaining the patient's temperature, and providing overall support.2–4,24,25 Prehospital Care Considerations As with any situation, providers should ensure that the basics of patient assessment and treatment take priority. Prehospital treatment is likely to be the foundation for continued treatment in the hospital. ASSESSMENT The patient assessment should begin with an overview of the patient's overall appearance. When possible, obtain a detailed physical assessment, review of systems and detailed medical history. Questions to consider include: What is the patient's level of consciousness? Do they have a chief complaint? Do they appear to be in obvious distress? Are there clues on scene that reveal a possible cause of their symptoms, such