Acute Biologic Crisis
Content
Lippincott Manual of Nursing Practice, 8 Ed
Acute Biologic Crisis
mikEL rlh mantong
ENVIRONMENTAL EMERGENCIES Heat Exhaustion
Heat exhaustion is the inadequacy or the collapse of peripheral circulation due to volume and electrolyte depletion. Heat exhaustion is one condition in the spectrum of heat-related illnesses, including heat rash, heat edema, heat cramps, and heat syncope. Untreated heat exhaustion may progress to heatstroke.
Heatstroke
Heatstroke is a medical emergency that can result in significant morbidity and mortality. It is defined as the combination of hyperpyrexia (105° F [40.6° C]) and neurologic symptoms. It is caused by a shutdown or failure of the heat-regulating mechanisms of the body.
Primary Assessment and Interventions
y y y Assess airway, breathing, and circulation. LOC may be altered. Expect to intervene immediately if cardiovascular collapse occurs. Obtain a history from accompanying person about environmental conditions, activity, underlying health, and medications that may have contributed to heatstroke. Perform a neurologic assessment. o Initially, the patient may exhibit bizarre behavior or irritability. This may progress to confusion, combativeness, deliriousness, and coma. Other central nervous system (CNS) disturbances include tremors, seizures, fixed and dilated pupils, and decerebrate or decorticate posturing. Temperature greater than 105° F. Hypotension. Rapid pulse; may be bounding or weak. Rapid respirations.
Primary Assessment and Interventions
y y Expect the patient to be alert without significant cardiorespiratory or neurologic compromise. If vital functions are significantly impaired, suspect secondary condition, such as MI or stroke. Obtain history of headache, fatigue, dizziness, muscle cramping, and nausea. Inspect skin usually pale, ashen, and moist. The temperature may be normal, slightly elevated, or as high as 104° F (40° C). Measure vital signs for hypotension, orthostatic changes, tachycardia, and tachypnea. The patient will be awake but may give a history of syncope or confusion. Laboratory analysis will show hemoconcentration and hyponatremia (if sodium depletion is the primary problem) or hypernatremia (if water depletion is the primary problem). The ECG may show dysrhythmias without evidence of infarction. Move the patient to a cool environment, and remove all clothing. Position the patient supine with the feet slightly elevated. If the patient complains of nausea or vomiting, do not give fluids by mouth. Start an I.V. line with Ringer's lactate or normal saline until electrolyte results are confirmed. Monitor the patient for changes in the cardiac rhythm and vital signs. Vital signs should be taken at least every 15 minutes until the patient is stable. Provide fans and cool sponge baths as cooling methods. Provide patient education. o Advise the patient to avoid immediate reexposure to high temperatures; the patient may remain hypersensitive to high temperatures for a considerable length of time. Emphasize the importance of maintaining an adequate fluid intake, wearing loose clothing, and reducing activity in hot weather. Athletes should monitor fluid losses, replace fluids, and use a gradual approach to physical conditioning, allowing sufficient time for acclimatization.
Subsequent Assessment
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Subsequent Assessment
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Assess vital signs. o o o o
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General Interventions
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The skin may appear flushed and hot; in early heatstroke, the skin may be moist, but, as the heatstroke progresses, the skin will become dry as the body loses its ability to sweat. ABGs show metabolic acidosis. Provide cooling measures. o o Reduce the core (internal) temperature to 102° F (38.9° C) as rapidly as possible. Evaporative cooling is the most efficient. Spray tepid water on the skin while electric fans are used to blow continuously over the patient to augment heat dissipation. Apply ice packs to neck, groin, axillae, and scalp (areas of maximal heat transfer). Soak sheets/towels in ice water and place on patient, using fans to accelerate evaporation/cooling rate. Immersion in cold water is contraindicated. If the temperature fails to decrease, initiate core cooling: iced saline lavage of stomach, cool fluid peritoneal dialysis, cool fluid bladder irrigation, or cool fluid chest irrigations. Place the patient on a hypothermia blanket. Discontinue active cooling when the temperature reaches 102° F. In most cases, this will reduce the
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General Interventions
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Lippincott Manual of Nursing Practice, 8 Ed
Acute Biologic Crisis
mikEL rlh mantong
chance of overcooling because the body temperature will continue to fall after cessation of cooling. y Oxygenate patient to supply tissue needs that are exaggerated by the hypermetabolic condition: 100% nonrebreather mask or intubate the patient if necessary to support a failing cardiorespiratory system. Monitor condition. o Monitor and record the core temperature continually during cooling process to avoid hypothermia; also, hyperthermia may recur spontaneously within 3 to 4 hours. Monitor the vital signs continuously, including ECG, CVP, blood pressure, pulse, and respiratory rate. Perform frequent (every 30 minutes) neurologic assessments. Start I.V. infusion using Ringer's lactate to replace fluid losses, maintain adequate circulation, and facilitate cooling. At least one I.V. line should be a central line. Fluid replacement is based on the patient's response and laboratory results. Dialysis for renal failure. Diuretics, such as mannitol (Osmitrol), to promote diuresis. Anticonvulsant agents to control seizures. Potassium for hypokalemia and sodium bicarbonate to correct metabolic acidosis, depending on laboratory results. Antipyretics are not useful in treating heatstroke. They may contribute to the complications of coagulopathy and hepatic damage. Intense shivering may be controlled by diazepam (Valium). Shivering will generate heat and increase the metabolic rate. Patients with depleted clotting factors may be treated with platelets or fresh frozen plasma.
Frostbite
Frostbite is trauma due to exposure to freezing temperatures that cause actual freezing of the tissue fluids in the cell and intracellular spaces, resulting in vascular damage. The areas of the body most likely to develop frostbite are the earlobes, cheeks, nose, hands, and feet. Frostbite may be classified as frostnip (initial response to cold, reversible), superficial frostbite, and deep frostbite.
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Primary Assessment and Interventions
y y y If not alert, assess airway, breathing, and circulation. Deficits may indicate coexisting hypothermia or underlying condition. Protect frostbitten interventions. tissue while performing other
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Subsequent Assessment
Frostnip y y History of gradual onset. Skin appears white.
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Replace fluids. o
y Numb, pain-free. Superficial Frostbite y y y Damage is limited to the skin and subcutaneous tissue. The skin will appear white and waxy. On palpation, the skin will feel stiff but the underlying tissue will be pliable, soft, and have its normal bounce.
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Other measures: o o o o
y Sensation is absent. Deep Frostbite y y y Skin will appear white, yellow-white, or mottled bluewhite. On palpation, the surface will feel frozen and the underlying tissue will feel frozen and hard. The affected part is completely insensitive to touch. Frostnip may be treated by placing a warm hand over the chilled area. Leave the frostbitten area alone until definitive rewarming is undertaken. Pad the extremity to prevent damage from trauma. Handle the part gently to avoid further mechanical injury. Remove all constricting clothing that can impair circulation, including watchbands and rings. Rewarming: o Rewarm the extremity by controlled and rapid rewarming. Rewarm with a temperature of 98.6° F to 104° F (37° C to 40° C) in a fairly large, tepid water bath where the part can be fully immersed without touching the side or bottom. If clothing, socks, or gloves are frozen to the extremity, they should be left on and removed after rewarming. More warm water may be added to the container by removing some cooled water and adding warm water. Slow rewarming is less effective and may increase tissue damage.
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General Interventions
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Insert an indwelling catheter with a urometer, and measure urine output at least hourly acute tubular necrosis is a complication of heatstroke. Perform continuous ECG monitoring and frequent cardiovascular assessments for possible ischemia, infarction, and dysrhythmias. Perform serial laboratory testing (clotting parameters, electrolytes, glucose, and serum enzymes). The patient should be admitted to an intensive care unit (ICU); complications can occur, including heart failure, cardiovascular collapse, hepatic failure, renal failure, disseminated intravascular coagulation, and rhabdomyolysis. Monitor the patient for the development of seizures, and provide for a safe environment in case of seizures.
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Lippincott Manual of Nursing Practice, 8 Ed
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Dry heat is not recommended for rewarming. The rewarming procedure may take 20 to 30 minutes. Rewarming is complete when the area is warm to the touch and pink or flushed.
Acute Biologic Crisis mikEL rlh mantong Primary Assessment and Interventions
y Assess airway and breathing. o o Spontaneous respirations may be extremely slow and imperceptible. Assist breathing and oxygenation with supplemental O2 at 100% or a bag-valve mask device. If intubation is necessary, extreme caution should be used because ventricular fibrillation may be precipitated. If the body temperature falls below 86° F (30° C), the heart sounds may not be audible even if the heart is still beating. Tissues conduct sound poorly at low temperatures. Blood pressure readings may be extremely difficult to hear because cold tissue conducts sound waves poorly. Pupil reflexes may be blocked by a decrease in cerebral blood flow, so the pupils may appear fixed and dilated. A patient with a heartbeat may present like a patient in cardiac arrest with fixed dilated pupils, no pulse, and no blood pressure. Provide CPR until further evaluation through ECG and hemodynamic monitoring.
Do not rub or massage a frostbitten extremity. The ice crystals in the tissue will lacerate delicate tissue. o
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Pharmacologic interventions: o Opioids for pain control. o o Antibiotics if there is an open wound. Tetanus prophylaxis. y o
Assess circulation.
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Protect the thawed part from infection. Large blisters may develop in 1 hour to a few days after rewarming; these blisters should not be broken. Place sterile gauze or cotton between affected fingers/toes to absorb moisture. Use strict aseptic technique during dressing changes. Frostbite injuries make the patient susceptible to infection. Make sure any dressings are loosely applied. Elevate the part to help control swelling. o Use a foot cradle to prevent contact with bedding if the feet are involved prevents further tissue injury. Perform a physical assessment to look for concomitant injury (soft-tissue injury, dehydration, alcohol coma, fat embolism due to fracture, immobility). Restore electrolyte balance; dehydration and hypovolemia occur frequently in frostbite victims. Whirlpool bath for the affected extremity to aid circulation, debride dead tissue, and help prevent infection. Escharotomy (incision through the eschar) to prevent further tissue damage, allow for normal circulation, and permit joint motion. Fasciotomy (incision in fascia to release pressure on the muscles, nerves, blood vessels) to treat compartment syndrome. Encourage hourly active motion of the affected digits to promote maximum restoration of function and to prevent contractures. Advise patient not to use tobacco because of the vasoconstrictive effects of nicotine, which further reduce the already deficient blood supply to injured tissues. Perform serial laboratory testing (urinalysis and serum enzymes) to monitor for the complications of rhabdomyolysis and subsequent renal failure. o
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Subsequent Assessment
y There is progressive deterioration marked by apathy, poor judgment, ataxia, dysarthria, drowsiness and, eventually, coma. Speech is slow and may be slurred. Shivering may be suppressed below a temperature of 90° F (32.2° C). Cardiac dysrhythmias cold disrupts the conduction system of the heart, and a variety of dysrhythmias may be seen. A hypothermic heart is extremely susceptible to ventricular fibrillation. Very cold hearts do not respond to drugs or defibrillation. The heartbeat and the blood pressure may be so weak that the peripheral pulsations become undetectable. Urine output may increase in response to peripheral vasoconstriction cold diuresis. Initial tachypnea followed by slow and shallow respirations, possibly two or three per minute in severe hypothermia. Fruity or acetone odor to the breath because the body may be metabolizing fat as a result of decreased insulin levels.
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Hypothermia
y Hypothermia is a condition in which the core (internal) temperature of the body is less than 95° F (35° C) as a result of exposure to cold. In response to a decreased core temperature, the body will attempt to produce or conserve more heat by (1) shivering, which produces heat through muscular activity; (2) peripheral vasoconstriction, to decrease heat loss; and (3) raising the basal metabolic rate. Hypothermia may be classified as mild, moderate, or severe.
General Interventions
Goal: rewarm without precipitating cardiac dysrhythmias. Supportive Measures y y Handle the patient carefully and gently to avoid triggering ventricular fibrillation. Continuously monitor core temperatures with a low reading rectal thermometer.
Lippincott Manual of Nursing Practice, 8 Ed
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Acute Biologic Crisis
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Continuously monitor ECG. Because you may be unable to obtain a pulse due to the hypothermia, rely on the cardiac monitor to determine the need for CPR. Monitor the patient's condition through vital signs, CVP, urine output, ABG values, and blood chemistry determinations. Maintain an arterial line for recording blood pressure and to facilitate blood sampling allows rapid detection of acid base disturbances and assessment of adequacy of ventilation and oxygenation.
TOXICOLOGIC EMERGENCIES
Toxicology is the study of the harmful effect of various substances on the body. Poisons are substances that are harmful to the body no matter how much or in what manner they enter the body. Drugs become toxic when they are taken in excess quantities or manners that are not therapeutic. Alcohol is considered a drug. The treatment goals of toxicologic emergencies are first, supportive; second, to prevent or minimize absorption; third, to provide an antidote.
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Start I.V. therapy with normal saline. Ringer's lactate is not recommended because the cold liver may not be able to metabolize the lactate. Rewarming Techniques y The type of rewarming depends on the degree of hypothermia. Rewarming should continue until the core temperature is 93.2° F (34° C). If the patient is in cardiac arrest, rewarming should continue until a temperature of 89.6° F (32° C) has been reached. Death in hypothermia is defined as a failure to revive after rewarming. y Passive external rewarming (temperature above 82.4° F [28° C]). o Remove all the wet or cold clothing, and replace with warm clothing. o Provide insulation by wrapping the patient in several blankets. o Provide warmed fluids to drink. o y Disadvantage: slow process. Provide external heat for the patient warm hot water bottles to the armpits, neck, or groin. (Do not apply hot water bottles directly to the skin.) Warm water immersion. Disadvantages: Causes peripheral vasodilation, returning cool blood to the core, causing an initial lowering of the core temperature. Acidosis due to the washing out of lactic acid from the peripheral tissues. An increase in the metabolic demands before the heart is warmed to meet these needs. Active external rewarming (temperature above 82.4° F). o
Ingested Poisons
Ingested poisons can produce immediate or delayed effects. Immediate injury is caused when the poison is caustic to the body tissues (ie, a strong acid or a strong alkali). Other ingested poisons must be absorbed into the bloodstream before they become harmful. Ingested poisoning may be accidental or intentional.
Primary Assessment and Interventions
y y Maintain an open airway some ingested substances may cause soft tissue swelling of the airway. Attain control of the airway, ventilation, and oxygenation; in the absence of cerebral or renal damage, the patient's prognosis depends largely on successful management and support of vital functions. Identify the poison. o Try to determine the product taken: where, when, why, how much, who witnessed the event, time since ingestion. o Call the poison control center in the area if an unknown toxic agent has been taken or if it is necessary to identify an antidote for a known toxic agent. Continue the focused assessment, observing any significant deviations from normal. Different poisons will affect the body in different ways. Obtain blood and urine tests for toxicology screening. Gastric contents may also be sent for toxicology screening in serious ingestions. Monitor neurologic status, including mentation; monitor the course of vital signs and neurologic status over time. Monitor for fluid and electrolyte imbalance.
Subsequent Assessment
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Active core rewarming (temperature below 82.4° F). o o o o o Inhalation of warmed, humidified oxygen by mask or ventilator. Warmed I.V. fluids. Warmed gastric lavage. Peritoneal dialysis with warmed standard dialysis solution. Mediastinal irrigation through open thoracotomy has been used successfully but has serious complications. Cardiopulmonary bypass. Disadvantage of active core rewarming is the invasiveness of the procedures.
General Interventions
Supportive Care y y y y Initiate large-bore I.V. access. Administer oxygen for respiratory depression. Monitor and treat shock. Prevent aspiration of gastric contents by positioning (on side with head down), use of oropharyngeal airway, and suctioning. Give supportive care to maintain vital organ systems. Insert an indwelling urinary catheter to monitor renal function.
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Lippincott Manual of Nursing Practice, 8 Ed
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Support the patient having seizures; many poisons excite the CNS, or the patient may convulse from oxygen deprivation.
Acute Biologic Crisis Primary Assessment
y Assess airway and breathing. o o
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Monitor and treat for complications: hypotension, coma, cardiac dysrhythmias, and seizures.
Psychiatric evaluations may be done after the patient is stabilized. Minimizing Absorption y The primary method for preventing or minimizing absorption is to administer activated charcoal with a cathartic to hasten excretion. Newer superactivated charcoals can reduce absorption of a toxic substance by as much as 50%. Administering activated charcoal plus a cathartic is just as effective or more effective than gastric lavage. o Administration of oral-activated charcoal absorbs the poison on the surface of its particles and allows it to pass with the stool. Multiple doses may be administered. Activated charcoal is usually mixed tap water to make a slurry.
Respiratory depression may be present. If the carbon monoxide poisoning is due to smoke inhalation, stridor (indicative of laryngeal edema due to thermal injury) may be present.
Primary Interventions
y Provide 100% oxygen by tight-fitting mask. (The elimination half-life of carboxyhemoglobin, in serum, for a person breathing room air is 5 hours 20 minutes. If the patient breathes 100% oxygen, the half-life is reduced to 80 minutes; 100% oxygen in a hyperbaric chamber will reduce the half-life to 23 minutes [treatment of choice].) Intubate if necessary to protect the airway. A thorough history is important: determine the type and length of exposure as well as possible other fumes inhaled. An underlying anemia, cardiac disease, or pulmonary disease may place a person at higher risk. Determine LOC the patient may appear intoxicated from cerebral hypoxia; confusion may progress rapidly to coma. Assess complaints of headache, muscular weakness, palpitation, dizziness. Inspect skin: may be pink, cherry red, or cyanotic and pale skin color is not a reliable sign. Monitor vital signs: increased respiratory and pulse rates are generally present. Be alert for altered breathing patterns and respiratory failure. Listen for rales or wheezes in the lungs (with smoke inhalation, indicates acute respiratory distress syndrome). Obtain arterial blood samples for carboxyhemoglobin levels. o Normal is less than 12%. o Severe carbon monoxide poisoning is present when levels are greater than 30% to 40%. History of exposure to carbon monoxide justifies immediate treatment. Goals are to reverse cerebral and myocardial hypoxia and hasten carbon monoxide elimination. Give 100% oxygen at atmospheric or hyperbaric pressures to reverse hypoxia and accelerate elimination of carbon monoxide. Patients should receive hyperbaric oxygen for CNS or cardiovascular system dysfunction. Use continuous ECG monitoring, treat dysrhythmias, and correct acid base and electrolyte abnormalities. Observe the patient constantly psychoses, spastic paralysis, visual disturbances, and deterioration of personality may persist after resuscitation and may be symptoms of permanent CNS damage.
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Subsequent Assessment
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Gastric lavage for the obtunded patient (see Procedure Guidelines 35-5, pages 1164 and 1165). Save gastric aspirate for toxicology screens. This procedure is controversial. Procedures to enhance the removal of the ingested substance if the patient is deteriorating. o o Forced diuresis with urine pH alteration to enhance renal clearance. Hemoperfusion (process of passing blood through an extracorporeal circuit and a cartridge containing an adsorbent, such as charcoal, after which the detoxified blood is returned to patient). Hemodialysis used in selected patients to purify blood and accelerate the elimination of circulating toxins. Repeated doses of charcoal nonabsorbed drugs/toxins. for binding
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General Interventions
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Gastric lavage may be used in conjunction with activated charcoal and a cathartic to maximize elimination of the substance.
Providing an Antidote y y An antidote is a chemical or physiologic antagonist that will neutralize the poison. Administer the specific antidote as early as possible to reverse or diminish effects of the toxin.
Carbon Monoxide Poisoning
Carbon monoxide poisoning is an example of an inhaled poison and is the result of the inhalation of the products of incomplete hydrocarbon combustion. It may occur as an industrial or household accident or as an attempted suicide. Carbon monoxide exerts its toxic effect by binding to circulating hemoglobin to reduce the oxygen-carrying capacity of the blood. The affinity between carbon monoxide and hemoglobin is 200 to 300 times that between oxygen and hemoglobin. (Carbon monoxide combines with hemoglobin to form carboxyhemoglobin.) As a result, tissue anoxia occurs.
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Insect Stings
Insect stings or bites are injected poisons that can produce either local or systemic reactions. Local reactions are characterized by
Lippincott Manual of Nursing Practice, 8 Ed
Acute Biologic Crisis
mikEL rlh mantong
Spray garbage cans with rapid-acting insecticide, and keep areas meticulously clean.
pain, erythema, and edema at the site of injury. Systemic reactions usually begin within minutes and produce mild to severe and lifethreatening reactions.
Primary Assessment and Interventions
y y y y y y Assess airway, breathing, and circulation. Anaphylactic reactions may produce unconsciousness, laryngeal edema, and cardiovascular collapse. Epinephrine is the drug of choice the amount and route depend on the severity of the reaction. Administer a bronchodilator bronchospasm. Prepare for CPR. to help relieve the
Snakebites
The majority of snakes in the United States are not poisonous. The poisonous varieties are pit vipers (rattlesnakes and copperheads) and coral snakes. Bites by these snakes may result in envenomation, an injected poisoning.
Primary Assessment and Interventions
y y y Assess airway, breathing, and circulation if patient is not alert. Severe envenomation may lead to neurotoxicity with respiratory paralysis, shock, coma, and death. Be prepared to resuscitate and provide advanced life support. Get a description of the snake, the time of the snakebite, and the location of the bite. Bites to the head and trunk may progress more rapidly and be more severe. o Pit vipers have triangular heads, vertical pupils, indentations between the eyes and nostrils, and long fangs. o Coral snakes are small, brightly colored, with short fangs and teeth behind them, and with a series of bands of yellow, red, yellow, and black (in that order). Assess for local reactions burning, pain, swelling, and numbness at the site. Local reactions to coral snakebites may be delayed several hours and may be very mild. A few hours after the bite, hemorrhagic blisters may occur at the site, and the entire extremity may become edematous. Watch for signs of systemic reactions, including nausea, sweating, weakness, lightheadedness, initial euphoria followed by drowsiness, difficulty in swallowing, paralysis of various muscle groups, signs of shock, seizures, and coma. Monitor vital signs closely because tachycardia or bradycardia may develop. Keep the patient calm and at rest in a recumbent position with the affected extremity immobilized. Administer oxygen. Start an I.V. line with normal saline or Ringer's lactate. Administer antivenin and be alert to allergic reaction (antivenin is horse serum-based). Administer vasopressors in the treatment of shock. Monitor for bleeding, and administer blood products for coagulopathy.
Initiate an I.V. with Ringer's lactate.
Subsequent Assessment
y y Obtain history of insect sting, previous exposure, and allergies. Inspect skin for local reaction erythema, edema, pain at site of injury as well as generalized pruritus, urticaria, and angioedema. Continue to monitor blood pressure and respiratory status for dyspnea, wheezing, and stridor. Apply ice packs to site to relieve pain. Elevate extremity with large edematous local reaction. Administer oral antihistamine for local reactions. Clean the wound thoroughly with soap and water or an antiseptic solution. Administer tetanus prophylaxis if not up to date. Provide patient education. o o o Always have epinephrine on hand (EpiPen). Wear medical emergency bracelets indicating hypersensitivity. Instructions when sting occurs: Take epinephrine immediately if stung. Remove stinger with one quick scrape of fingernail. Do not squeeze venom sac because this may cause additional venom to be injected. Report to nearest health care facility for observation. Avoid exposure. Avoid locales with stinging insects (camp and picnic sites). Stay away from insect feeding areas flower beds, ripe fruit orchards, garbage, fields of clover. Avoid going barefoot outdoors yellow jackets may nest on ground. Avoid perfumes, scented soaps, bright colors attract bees. Keep car windows closed.
Subsequent Assessment
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General Interventions
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Acute Biologic Crisis
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ENVIRONMENTAL EMERGENCIES Heat Exhaustion
Heat exhaustion is the inadequacy or the collapse of peripheral circulation due to volume and electrolyte depletion. Heat exhaustion is one condition in the spectrum of heat-related illnesses, including heat rash, heat edema, heat cramps, and heat syncope. Untreated heat exhaustion may progress to heatstroke.
Heatstroke
Heatstroke is a medical emergency that can result in significant morbidity and mortality. It is defined as the combination of hyperpyrexia (105° F [40.6° C]) and neurologic symptoms. It is caused by a shutdown or failure of the heat-regulating mechanisms of the body.
Primary Assessment and Interventions
y y y Assess airway, breathing, and circulation. LOC may be altered. Expect to intervene immediately if cardiovascular collapse occurs. Obtain a history from accompanying person about environmental conditions, activity, underlying health, and medications that may have contributed to heatstroke. Perform a neurologic assessment. o Initially, the patient may exhibit bizarre behavior or irritability. This may progress to confusion, combativeness, deliriousness, and coma. Other central nervous system (CNS) disturbances include tremors, seizures, fixed and dilated pupils, and decerebrate or decorticate posturing. Temperature greater than 105° F. Hypotension. Rapid pulse; may be bounding or weak. Rapid respirations.
Primary Assessment and Interventions
y y Expect the patient to be alert without significant cardiorespiratory or neurologic compromise. If vital functions are significantly impaired, suspect secondary condition, such as MI or stroke. Obtain history of headache, fatigue, dizziness, muscle cramping, and nausea. Inspect skin usually pale, ashen, and moist. The temperature may be normal, slightly elevated, or as high as 104° F (40° C). Measure vital signs for hypotension, orthostatic changes, tachycardia, and tachypnea. The patient will be awake but may give a history of syncope or confusion. Laboratory analysis will show hemoconcentration and hyponatremia (if sodium depletion is the primary problem) or hypernatremia (if water depletion is the primary problem). The ECG may show dysrhythmias without evidence of infarction. Move the patient to a cool environment, and remove all clothing. Position the patient supine with the feet slightly elevated. If the patient complains of nausea or vomiting, do not give fluids by mouth. Start an I.V. line with Ringer's lactate or normal saline until electrolyte results are confirmed. Monitor the patient for changes in the cardiac rhythm and vital signs. Vital signs should be taken at least every 15 minutes until the patient is stable. Provide fans and cool sponge baths as cooling methods. Provide patient education. o Advise the patient to avoid immediate reexposure to high temperatures; the patient may remain hypersensitive to high temperatures for a considerable length of time. Emphasize the importance of maintaining an adequate fluid intake, wearing loose clothing, and reducing activity in hot weather. Athletes should monitor fluid losses, replace fluids, and use a gradual approach to physical conditioning, allowing sufficient time for acclimatization.
Subsequent Assessment
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Subsequent Assessment
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General Interventions
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The skin may appear flushed and hot; in early heatstroke, the skin may be moist, but, as the heatstroke progresses, the skin will become dry as the body loses its ability to sweat. ABGs show metabolic acidosis. Provide cooling measures. o o Reduce the core (internal) temperature to 102° F (38.9° C) as rapidly as possible. Evaporative cooling is the most efficient. Spray tepid water on the skin while electric fans are used to blow continuously over the patient to augment heat dissipation. Apply ice packs to neck, groin, axillae, and scalp (areas of maximal heat transfer). Soak sheets/towels in ice water and place on patient, using fans to accelerate evaporation/cooling rate. Immersion in cold water is contraindicated. If the temperature fails to decrease, initiate core cooling: iced saline lavage of stomach, cool fluid peritoneal dialysis, cool fluid bladder irrigation, or cool fluid chest irrigations. Place the patient on a hypothermia blanket. Discontinue active cooling when the temperature reaches 102° F. In most cases, this will reduce the
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General Interventions
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Lippincott Manual of Nursing Practice, 8 Ed
Acute Biologic Crisis
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chance of overcooling because the body temperature will continue to fall after cessation of cooling. y Oxygenate patient to supply tissue needs that are exaggerated by the hypermetabolic condition: 100% nonrebreather mask or intubate the patient if necessary to support a failing cardiorespiratory system. Monitor condition. o Monitor and record the core temperature continually during cooling process to avoid hypothermia; also, hyperthermia may recur spontaneously within 3 to 4 hours. Monitor the vital signs continuously, including ECG, CVP, blood pressure, pulse, and respiratory rate. Perform frequent (every 30 minutes) neurologic assessments. Start I.V. infusion using Ringer's lactate to replace fluid losses, maintain adequate circulation, and facilitate cooling. At least one I.V. line should be a central line. Fluid replacement is based on the patient's response and laboratory results. Dialysis for renal failure. Diuretics, such as mannitol (Osmitrol), to promote diuresis. Anticonvulsant agents to control seizures. Potassium for hypokalemia and sodium bicarbonate to correct metabolic acidosis, depending on laboratory results. Antipyretics are not useful in treating heatstroke. They may contribute to the complications of coagulopathy and hepatic damage. Intense shivering may be controlled by diazepam (Valium). Shivering will generate heat and increase the metabolic rate. Patients with depleted clotting factors may be treated with platelets or fresh frozen plasma.
Frostbite
Frostbite is trauma due to exposure to freezing temperatures that cause actual freezing of the tissue fluids in the cell and intracellular spaces, resulting in vascular damage. The areas of the body most likely to develop frostbite are the earlobes, cheeks, nose, hands, and feet. Frostbite may be classified as frostnip (initial response to cold, reversible), superficial frostbite, and deep frostbite.
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Primary Assessment and Interventions
y y y If not alert, assess airway, breathing, and circulation. Deficits may indicate coexisting hypothermia or underlying condition. Protect frostbitten interventions. tissue while performing other
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Subsequent Assessment
Frostnip y y History of gradual onset. Skin appears white.
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y Numb, pain-free. Superficial Frostbite y y y Damage is limited to the skin and subcutaneous tissue. The skin will appear white and waxy. On palpation, the skin will feel stiff but the underlying tissue will be pliable, soft, and have its normal bounce.
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y Sensation is absent. Deep Frostbite y y y Skin will appear white, yellow-white, or mottled bluewhite. On palpation, the surface will feel frozen and the underlying tissue will feel frozen and hard. The affected part is completely insensitive to touch. Frostnip may be treated by placing a warm hand over the chilled area. Leave the frostbitten area alone until definitive rewarming is undertaken. Pad the extremity to prevent damage from trauma. Handle the part gently to avoid further mechanical injury. Remove all constricting clothing that can impair circulation, including watchbands and rings. Rewarming: o Rewarm the extremity by controlled and rapid rewarming. Rewarm with a temperature of 98.6° F to 104° F (37° C to 40° C) in a fairly large, tepid water bath where the part can be fully immersed without touching the side or bottom. If clothing, socks, or gloves are frozen to the extremity, they should be left on and removed after rewarming. More warm water may be added to the container by removing some cooled water and adding warm water. Slow rewarming is less effective and may increase tissue damage.
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General Interventions
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Insert an indwelling catheter with a urometer, and measure urine output at least hourly acute tubular necrosis is a complication of heatstroke. Perform continuous ECG monitoring and frequent cardiovascular assessments for possible ischemia, infarction, and dysrhythmias. Perform serial laboratory testing (clotting parameters, electrolytes, glucose, and serum enzymes). The patient should be admitted to an intensive care unit (ICU); complications can occur, including heart failure, cardiovascular collapse, hepatic failure, renal failure, disseminated intravascular coagulation, and rhabdomyolysis. Monitor the patient for the development of seizures, and provide for a safe environment in case of seizures.
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Dry heat is not recommended for rewarming. The rewarming procedure may take 20 to 30 minutes. Rewarming is complete when the area is warm to the touch and pink or flushed.
Acute Biologic Crisis mikEL rlh mantong Primary Assessment and Interventions
y Assess airway and breathing. o o Spontaneous respirations may be extremely slow and imperceptible. Assist breathing and oxygenation with supplemental O2 at 100% or a bag-valve mask device. If intubation is necessary, extreme caution should be used because ventricular fibrillation may be precipitated. If the body temperature falls below 86° F (30° C), the heart sounds may not be audible even if the heart is still beating. Tissues conduct sound poorly at low temperatures. Blood pressure readings may be extremely difficult to hear because cold tissue conducts sound waves poorly. Pupil reflexes may be blocked by a decrease in cerebral blood flow, so the pupils may appear fixed and dilated. A patient with a heartbeat may present like a patient in cardiac arrest with fixed dilated pupils, no pulse, and no blood pressure. Provide CPR until further evaluation through ECG and hemodynamic monitoring.
Do not rub or massage a frostbitten extremity. The ice crystals in the tissue will lacerate delicate tissue. o
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Pharmacologic interventions: o Opioids for pain control. o o Antibiotics if there is an open wound. Tetanus prophylaxis. y o
Assess circulation.
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Protect the thawed part from infection. Large blisters may develop in 1 hour to a few days after rewarming; these blisters should not be broken. Place sterile gauze or cotton between affected fingers/toes to absorb moisture. Use strict aseptic technique during dressing changes. Frostbite injuries make the patient susceptible to infection. Make sure any dressings are loosely applied. Elevate the part to help control swelling. o Use a foot cradle to prevent contact with bedding if the feet are involved prevents further tissue injury. Perform a physical assessment to look for concomitant injury (soft-tissue injury, dehydration, alcohol coma, fat embolism due to fracture, immobility). Restore electrolyte balance; dehydration and hypovolemia occur frequently in frostbite victims. Whirlpool bath for the affected extremity to aid circulation, debride dead tissue, and help prevent infection. Escharotomy (incision through the eschar) to prevent further tissue damage, allow for normal circulation, and permit joint motion. Fasciotomy (incision in fascia to release pressure on the muscles, nerves, blood vessels) to treat compartment syndrome. Encourage hourly active motion of the affected digits to promote maximum restoration of function and to prevent contractures. Advise patient not to use tobacco because of the vasoconstrictive effects of nicotine, which further reduce the already deficient blood supply to injured tissues. Perform serial laboratory testing (urinalysis and serum enzymes) to monitor for the complications of rhabdomyolysis and subsequent renal failure. o
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Subsequent Assessment
y There is progressive deterioration marked by apathy, poor judgment, ataxia, dysarthria, drowsiness and, eventually, coma. Speech is slow and may be slurred. Shivering may be suppressed below a temperature of 90° F (32.2° C). Cardiac dysrhythmias cold disrupts the conduction system of the heart, and a variety of dysrhythmias may be seen. A hypothermic heart is extremely susceptible to ventricular fibrillation. Very cold hearts do not respond to drugs or defibrillation. The heartbeat and the blood pressure may be so weak that the peripheral pulsations become undetectable. Urine output may increase in response to peripheral vasoconstriction cold diuresis. Initial tachypnea followed by slow and shallow respirations, possibly two or three per minute in severe hypothermia. Fruity or acetone odor to the breath because the body may be metabolizing fat as a result of decreased insulin levels.
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Hypothermia
y Hypothermia is a condition in which the core (internal) temperature of the body is less than 95° F (35° C) as a result of exposure to cold. In response to a decreased core temperature, the body will attempt to produce or conserve more heat by (1) shivering, which produces heat through muscular activity; (2) peripheral vasoconstriction, to decrease heat loss; and (3) raising the basal metabolic rate. Hypothermia may be classified as mild, moderate, or severe.
General Interventions
Goal: rewarm without precipitating cardiac dysrhythmias. Supportive Measures y y Handle the patient carefully and gently to avoid triggering ventricular fibrillation. Continuously monitor core temperatures with a low reading rectal thermometer.
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Continuously monitor ECG. Because you may be unable to obtain a pulse due to the hypothermia, rely on the cardiac monitor to determine the need for CPR. Monitor the patient's condition through vital signs, CVP, urine output, ABG values, and blood chemistry determinations. Maintain an arterial line for recording blood pressure and to facilitate blood sampling allows rapid detection of acid base disturbances and assessment of adequacy of ventilation and oxygenation.
TOXICOLOGIC EMERGENCIES
Toxicology is the study of the harmful effect of various substances on the body. Poisons are substances that are harmful to the body no matter how much or in what manner they enter the body. Drugs become toxic when they are taken in excess quantities or manners that are not therapeutic. Alcohol is considered a drug. The treatment goals of toxicologic emergencies are first, supportive; second, to prevent or minimize absorption; third, to provide an antidote.
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Start I.V. therapy with normal saline. Ringer's lactate is not recommended because the cold liver may not be able to metabolize the lactate. Rewarming Techniques y The type of rewarming depends on the degree of hypothermia. Rewarming should continue until the core temperature is 93.2° F (34° C). If the patient is in cardiac arrest, rewarming should continue until a temperature of 89.6° F (32° C) has been reached. Death in hypothermia is defined as a failure to revive after rewarming. y Passive external rewarming (temperature above 82.4° F [28° C]). o Remove all the wet or cold clothing, and replace with warm clothing. o Provide insulation by wrapping the patient in several blankets. o Provide warmed fluids to drink. o y Disadvantage: slow process. Provide external heat for the patient warm hot water bottles to the armpits, neck, or groin. (Do not apply hot water bottles directly to the skin.) Warm water immersion. Disadvantages: Causes peripheral vasodilation, returning cool blood to the core, causing an initial lowering of the core temperature. Acidosis due to the washing out of lactic acid from the peripheral tissues. An increase in the metabolic demands before the heart is warmed to meet these needs. Active external rewarming (temperature above 82.4° F). o
Ingested Poisons
Ingested poisons can produce immediate or delayed effects. Immediate injury is caused when the poison is caustic to the body tissues (ie, a strong acid or a strong alkali). Other ingested poisons must be absorbed into the bloodstream before they become harmful. Ingested poisoning may be accidental or intentional.
Primary Assessment and Interventions
y y Maintain an open airway some ingested substances may cause soft tissue swelling of the airway. Attain control of the airway, ventilation, and oxygenation; in the absence of cerebral or renal damage, the patient's prognosis depends largely on successful management and support of vital functions. Identify the poison. o Try to determine the product taken: where, when, why, how much, who witnessed the event, time since ingestion. o Call the poison control center in the area if an unknown toxic agent has been taken or if it is necessary to identify an antidote for a known toxic agent. Continue the focused assessment, observing any significant deviations from normal. Different poisons will affect the body in different ways. Obtain blood and urine tests for toxicology screening. Gastric contents may also be sent for toxicology screening in serious ingestions. Monitor neurologic status, including mentation; monitor the course of vital signs and neurologic status over time. Monitor for fluid and electrolyte imbalance.
Subsequent Assessment
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Active core rewarming (temperature below 82.4° F). o o o o o Inhalation of warmed, humidified oxygen by mask or ventilator. Warmed I.V. fluids. Warmed gastric lavage. Peritoneal dialysis with warmed standard dialysis solution. Mediastinal irrigation through open thoracotomy has been used successfully but has serious complications. Cardiopulmonary bypass. Disadvantage of active core rewarming is the invasiveness of the procedures.
General Interventions
Supportive Care y y y y Initiate large-bore I.V. access. Administer oxygen for respiratory depression. Monitor and treat shock. Prevent aspiration of gastric contents by positioning (on side with head down), use of oropharyngeal airway, and suctioning. Give supportive care to maintain vital organ systems. Insert an indwelling urinary catheter to monitor renal function.
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Support the patient having seizures; many poisons excite the CNS, or the patient may convulse from oxygen deprivation.
Acute Biologic Crisis Primary Assessment
y Assess airway and breathing. o o
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Monitor and treat for complications: hypotension, coma, cardiac dysrhythmias, and seizures.
Psychiatric evaluations may be done after the patient is stabilized. Minimizing Absorption y The primary method for preventing or minimizing absorption is to administer activated charcoal with a cathartic to hasten excretion. Newer superactivated charcoals can reduce absorption of a toxic substance by as much as 50%. Administering activated charcoal plus a cathartic is just as effective or more effective than gastric lavage. o Administration of oral-activated charcoal absorbs the poison on the surface of its particles and allows it to pass with the stool. Multiple doses may be administered. Activated charcoal is usually mixed tap water to make a slurry.
Respiratory depression may be present. If the carbon monoxide poisoning is due to smoke inhalation, stridor (indicative of laryngeal edema due to thermal injury) may be present.
Primary Interventions
y Provide 100% oxygen by tight-fitting mask. (The elimination half-life of carboxyhemoglobin, in serum, for a person breathing room air is 5 hours 20 minutes. If the patient breathes 100% oxygen, the half-life is reduced to 80 minutes; 100% oxygen in a hyperbaric chamber will reduce the half-life to 23 minutes [treatment of choice].) Intubate if necessary to protect the airway. A thorough history is important: determine the type and length of exposure as well as possible other fumes inhaled. An underlying anemia, cardiac disease, or pulmonary disease may place a person at higher risk. Determine LOC the patient may appear intoxicated from cerebral hypoxia; confusion may progress rapidly to coma. Assess complaints of headache, muscular weakness, palpitation, dizziness. Inspect skin: may be pink, cherry red, or cyanotic and pale skin color is not a reliable sign. Monitor vital signs: increased respiratory and pulse rates are generally present. Be alert for altered breathing patterns and respiratory failure. Listen for rales or wheezes in the lungs (with smoke inhalation, indicates acute respiratory distress syndrome). Obtain arterial blood samples for carboxyhemoglobin levels. o Normal is less than 12%. o Severe carbon monoxide poisoning is present when levels are greater than 30% to 40%. History of exposure to carbon monoxide justifies immediate treatment. Goals are to reverse cerebral and myocardial hypoxia and hasten carbon monoxide elimination. Give 100% oxygen at atmospheric or hyperbaric pressures to reverse hypoxia and accelerate elimination of carbon monoxide. Patients should receive hyperbaric oxygen for CNS or cardiovascular system dysfunction. Use continuous ECG monitoring, treat dysrhythmias, and correct acid base and electrolyte abnormalities. Observe the patient constantly psychoses, spastic paralysis, visual disturbances, and deterioration of personality may persist after resuscitation and may be symptoms of permanent CNS damage.
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Subsequent Assessment
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Gastric lavage for the obtunded patient (see Procedure Guidelines 35-5, pages 1164 and 1165). Save gastric aspirate for toxicology screens. This procedure is controversial. Procedures to enhance the removal of the ingested substance if the patient is deteriorating. o o Forced diuresis with urine pH alteration to enhance renal clearance. Hemoperfusion (process of passing blood through an extracorporeal circuit and a cartridge containing an adsorbent, such as charcoal, after which the detoxified blood is returned to patient). Hemodialysis used in selected patients to purify blood and accelerate the elimination of circulating toxins. Repeated doses of charcoal nonabsorbed drugs/toxins. for binding
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General Interventions
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Gastric lavage may be used in conjunction with activated charcoal and a cathartic to maximize elimination of the substance.
Providing an Antidote y y An antidote is a chemical or physiologic antagonist that will neutralize the poison. Administer the specific antidote as early as possible to reverse or diminish effects of the toxin.
Carbon Monoxide Poisoning
Carbon monoxide poisoning is an example of an inhaled poison and is the result of the inhalation of the products of incomplete hydrocarbon combustion. It may occur as an industrial or household accident or as an attempted suicide. Carbon monoxide exerts its toxic effect by binding to circulating hemoglobin to reduce the oxygen-carrying capacity of the blood. The affinity between carbon monoxide and hemoglobin is 200 to 300 times that between oxygen and hemoglobin. (Carbon monoxide combines with hemoglobin to form carboxyhemoglobin.) As a result, tissue anoxia occurs.
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Insect Stings
Insect stings or bites are injected poisons that can produce either local or systemic reactions. Local reactions are characterized by
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Spray garbage cans with rapid-acting insecticide, and keep areas meticulously clean.
pain, erythema, and edema at the site of injury. Systemic reactions usually begin within minutes and produce mild to severe and lifethreatening reactions.
Primary Assessment and Interventions
y y y y y y Assess airway, breathing, and circulation. Anaphylactic reactions may produce unconsciousness, laryngeal edema, and cardiovascular collapse. Epinephrine is the drug of choice the amount and route depend on the severity of the reaction. Administer a bronchodilator bronchospasm. Prepare for CPR. to help relieve the
Snakebites
The majority of snakes in the United States are not poisonous. The poisonous varieties are pit vipers (rattlesnakes and copperheads) and coral snakes. Bites by these snakes may result in envenomation, an injected poisoning.
Primary Assessment and Interventions
y y y Assess airway, breathing, and circulation if patient is not alert. Severe envenomation may lead to neurotoxicity with respiratory paralysis, shock, coma, and death. Be prepared to resuscitate and provide advanced life support. Get a description of the snake, the time of the snakebite, and the location of the bite. Bites to the head and trunk may progress more rapidly and be more severe. o Pit vipers have triangular heads, vertical pupils, indentations between the eyes and nostrils, and long fangs. o Coral snakes are small, brightly colored, with short fangs and teeth behind them, and with a series of bands of yellow, red, yellow, and black (in that order). Assess for local reactions burning, pain, swelling, and numbness at the site. Local reactions to coral snakebites may be delayed several hours and may be very mild. A few hours after the bite, hemorrhagic blisters may occur at the site, and the entire extremity may become edematous. Watch for signs of systemic reactions, including nausea, sweating, weakness, lightheadedness, initial euphoria followed by drowsiness, difficulty in swallowing, paralysis of various muscle groups, signs of shock, seizures, and coma. Monitor vital signs closely because tachycardia or bradycardia may develop. Keep the patient calm and at rest in a recumbent position with the affected extremity immobilized. Administer oxygen. Start an I.V. line with normal saline or Ringer's lactate. Administer antivenin and be alert to allergic reaction (antivenin is horse serum-based). Administer vasopressors in the treatment of shock. Monitor for bleeding, and administer blood products for coagulopathy.
Initiate an I.V. with Ringer's lactate.
Subsequent Assessment
y y Obtain history of insect sting, previous exposure, and allergies. Inspect skin for local reaction erythema, edema, pain at site of injury as well as generalized pruritus, urticaria, and angioedema. Continue to monitor blood pressure and respiratory status for dyspnea, wheezing, and stridor. Apply ice packs to site to relieve pain. Elevate extremity with large edematous local reaction. Administer oral antihistamine for local reactions. Clean the wound thoroughly with soap and water or an antiseptic solution. Administer tetanus prophylaxis if not up to date. Provide patient education. o o o Always have epinephrine on hand (EpiPen). Wear medical emergency bracelets indicating hypersensitivity. Instructions when sting occurs: Take epinephrine immediately if stung. Remove stinger with one quick scrape of fingernail. Do not squeeze venom sac because this may cause additional venom to be injected. Report to nearest health care facility for observation. Avoid exposure. Avoid locales with stinging insects (camp and picnic sites). Stay away from insect feeding areas flower beds, ripe fruit orchards, garbage, fields of clover. Avoid going barefoot outdoors yellow jackets may nest on ground. Avoid perfumes, scented soaps, bright colors attract bees. Keep car windows closed.
Subsequent Assessment
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