The geriatric population makes up a large portion of the emergency patient population. Geriatric patients have less reserve and more comorbid diseases. They are frequently on multiple medications and are more likely to require aggressive treatment during acute illness. Although it may not be obvious, it is important to recognize the signs of shock as early as possible. Special care and monitoring should be used when resuscitating the elderly. The use of bedside ultrasound and monitoring for coagulopathies are discussed. Clinicians should be constantly vigilant and reassess throughout diagnosis and treatment. Ethical considerations in this population need to be considered on an individual basis.
Key points
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Do not use age as the sole criteria to perform or withhold any type of resuscitation.
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Early signs of shock may not be apparent in the elderly.
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Do not assume that the cause of shock is apparent. Always keep a high level of suspicion for hemorrhage and obstructive forms of shock.
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Use bedside ultrasound as an adjunct to diagnosis and care.
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Frequent reassessment is necessary to gauge the effectiveness of resuscitation.
Introduction
The geriatric population is an ever growing demographic in the United States, and thus a significant representation of health care recipients. If 65 years of age is used as the demarcation, in 2010 a total of 13% of the US population was geriatric. Accordingly, by 2030 the percentage is projected to increase to more than 20%. A significant portion of this population will become dependent on the health care system. By the time a person reaches 65 years of age they will have on average three chronic medical conditions and close to a 20% risk for hospitalization per year. According to one source by the year 2050, a total of 39% of trauma admissions will be geriatric patients. Currently, nearly two-thirds of intensive care unit beds are occupied by those greater than 65 years of age. Emergency medical treatment of this expanding population is complicated by their relative fragility caused by nothing more than normal physiologic changes that occur with age. In general, these changes cause the individual to be at greater risk for illness and injury. In addition, many of these individuals have comorbidities that make resuscitation more complex. Trauma, sepsis, gastrointestinal (GI) bleeding, and cardiac arrest have all been shown to have an age-related increase in mortality. Most recent studies show that much of this increase is caused by comorbid disease states and not age alone. Comorbidities can decrease physiologic reserve and alter the body’s ability to resist external insults.
Introduction
The geriatric population is an ever growing demographic in the United States, and thus a significant representation of health care recipients. If 65 years of age is used as the demarcation, in 2010 a total of 13% of the US population was geriatric. Accordingly, by 2030 the percentage is projected to increase to more than 20%. A significant portion of this population will become dependent on the health care system. By the time a person reaches 65 years of age they will have on average three chronic medical conditions and close to a 20% risk for hospitalization per year. According to one source by the year 2050, a total of 39% of trauma admissions will be geriatric patients. Currently, nearly two-thirds of intensive care unit beds are occupied by those greater than 65 years of age. Emergency medical treatment of this expanding population is complicated by their relative fragility caused by nothing more than normal physiologic changes that occur with age. In general, these changes cause the individual to be at greater risk for illness and injury. In addition, many of these individuals have comorbidities that make resuscitation more complex. Trauma, sepsis, gastrointestinal (GI) bleeding, and cardiac arrest have all been shown to have an age-related increase in mortality. Most recent studies show that much of this increase is caused by comorbid disease states and not age alone. Comorbidities can decrease physiologic reserve and alter the body’s ability to resist external insults.
Ethical considerations
Before starting resuscitation a clinician should try to determine the patient’s wishes, whether they have advance directives in place, and evaluate the patient’s condition for medical futility. This is true in all populations but is more frequently an issue in the elderly. In a perfect world the patient or the patient’s agent/proxy would be readily available to express the patient’s wishes. More often the patient arrives by emergency medical service with limited information. The advance health care directives or advance directives were developed to provide a practical process for ensuring patient autonomy and self-determination at the end of life. Even though there are distinctions, for this discussion advance directives are used interchangeably with living will, a do-not-resuscitate order, or a Physician Orders for Life-Sustaining Treatment. These directives allow physicians and family to make treatment decisions that reflect the decisions that the patient would have made for himself or herself. Advance directives are not simply about avoiding treatment that would prolong life in undesirable conditions. They have become increasingly detailed and specific, often containing patient preferences for a variety of medical treatments in hypothetical medical scenarios. Most of the advance directives that affect the provider at this stage of resuscitation involve do-not-resuscitate or do-not-intubate orders.
When available and known, most physicians feel comfortable complying with these patient decisions. When physicians fail to comply with a patient’s advance directive, the patient or their representative may bring a civil law suit for damages. Unfortunately, the advance directives are often not known or not available at the initial stages of resuscitation. Often a call to the patient’s home/facility or a call to the next of kin needs to be made to clarify the proper action. If there is no information available then resuscitation should proceed as the physician deems appropriate. If an action, such as intubation, is taken and later the patient’s wishes to the contrary become known, it should be noted that there is little ethical distinction between not initiating care and withdrawing care. When patient’s wishes become known the providers should make every effort to apply them. Physicians may override the advance directive, but this should only be done in rare instances where there is evidence that the patient’s wishes have changed since the advance directives were written.
Not every patient presenting to the emergency department should be resuscitated. If the medical providers believe that an intervention is futile or that it may only bring harm to the patient, they should choose not to perform that intervention. Arguments against providing care that is futile include potential harm to patients; family members or caregivers with little or no likely benefits; and to a lesser extent, the diversion of resources that might otherwise be used to provide care to those patients who could positively respond to such care. The physician’s judgment should be unbiased, and should be based on available scientific evidence, and societal and professional standards. It should include an assessment of the likelihood that a patient could physically recover as a result of treatment, or the likelihood of such treatment to relieve a patient’s suffering. The American College of Emergency Physicians has a policy statement that provides some guidance and protection to the physician. The best course of action is to engage the patient and/or their proxies in the decision as to what is best for the patient and continue accordingly.
Resuscitation
Once the decision to resuscitate has been made, the emergency physician should act rapidly. There is a tendency to treat older persons less aggressively. However, recognizing illness early and starting appropriate therapy is essential in the geriatric population. Aggressive, early treatment has been shown to improve survival in the elderly. It is important to consider criteria other than just chronologic age, such as recent performance level, quality of life, comorbidities, and patient preference, when determining the aggressiveness of care. Efforts should be aimed at early recognition of shock states because the longer a patient is in extremis the lower the chance of full recovery. Elderly patients have less reserve and injuries and insults that seem minor in isolation may have catastrophic consequences in this population.
Airway
The geriatric airway evaluation starts with making sure that the airway is clear and patent, evaluating the neck and tracheal area for injury, swelling, or crepitus. Make note of facial hair, dentures, or dental appliances. Geriatric patients are more difficult to bag-valve-mask ventilate, even in the absence of these obstructions. There are several physiologic changes in the geriatric airway that should be noted. There is a loss of muscular pharyngeal support, making the elderly more susceptible to upper airway obstruction. There is also a decrease in respiratory effort in response to upper airway occlusion. The protective mechanisms of coughing and swallowing also diminish with age, placing geriatric individuals at higher risk for aspiration. Factors associated with a difficult airway that worsen with age include limited mouth opening caused by temporomandibular joint stiffening, limited mandibular protrusion, decreased thyromental distance, and decreased submandibular compliance. An individual’s Mallampati score increases with age and neck mobility decreases. These factors combine to make most geriatric airways by definition a difficult airway. If intubation becomes necessary the goals are to safely and quickly secure the airway, while minimizing the risk of aspiration without worsening shock. It is essential to prepare for a difficult airway with available fiberoptic and other airway adjuncts. Be prepared to use the LMA as a temporary or definitive airway when other options fail. Rapid sequence intubation or modified rapid sequence intubation is most commonly used to facilitate intubation and minimize the risk of active regurgitation.
Breathing
The second step is to assess breathing and ventilation. Examine the patient visually and with a stethoscope. Palpate the chest wall, and look for old surgical scars, pacemakers, and ports that may give clues to the past medical history. When treating geriatric patients at this stage of the examination, there are several important physiologic changes to be noted. Weakened respiratory muscles and decreased elastic recoil of the lungs may lead to reduced vital capacity, functional residual capacity, and forced expiratory volume in 1 second. There is a significant increase in dead space, sometimes called “senile emphysema,” which decreases the respiratory reserve. These changes indicate that this population is at increased risk for respiratory failure and acute lung injury, thus leading to intubation and support on mechanical ventilation.
The universal use of supplemental oxygen in patients with major illness has been the mainstay of the initial stabilization. However, recent studies have called this practice into question. Studies on diseases, such as myocardial infarction (MI) and congestive heart failure, have shown an increase in mortality with the use of supplemental oxygen. Furthermore, the geriatric population has more comorbid diseases, such as chronic obstructive pulmonary disease, which predispose to hypercarbia when patients are on supplemental oxygen. Depending on the case, when an oxygen saturation level becomes available, supplemental oxygen can be given to maintain oxygen saturation in the low 90% range or a Pa o 2 greater than or equal to 60 mm Hg. However, oxygen may not be needed in patients with normal oxygenation.
When available, use continuous pulse oximetry and capnometry or capnography to assess oxygenation and ventilation. Elderly patients often have a diminished response to hypercarbia, hypoxia, and acidosis. They may have a normal respiratory rate because it takes them longer to compensate. While examining the chest be aware of the increased fragility of the chest wall in geriatric patients. The elderly have a decreased ability to tolerate chest wall trauma. These patients are more likely to sustain injuries, such as rib fractures, sternal fractures, flail chest, hemopneumothorax, and pulmonary contusion and/or cardiac contusion.
Intubation
Intubation may be considered for a variety of reasons, including respiratory failure, patient fatigue, and airway protection. Although the decision is usually determined by clinical criteria, intubation should be considered when patients have a respiratory rate of greater than 40 breaths per minute, or a Pa o 2 less than 60 mm Hg or a Pa co 2 greater than 50 mm Hg. The decision to intubate is always an important one, but this is especially true in the elderly. For this population there is a higher rate of aspiration, ventilator-associated pneumonia, and failure to wean from the ventilator. Consider noninvasive ventilation when attempting to delay or avoid intubation. It has been proven beneficial despite difficulty securing the appropriately fitting mask because of poor dentition, dental appliances, and altered mental status. Noninvasive ventilation has proven beneficial for chronic obstructive pulmonary disease where it has been shown to drastically reduce symptoms and the need for intubation. It has symptomatic benefit in congestive heart failure and may be advantageous in other respiratory processes.
Once the decision to intubate is made, orotracheal intubation using neuromuscular blockade should be used in most cases. Doses for neuromuscular blocking agents do not have to be altered in the elderly, regardless of their renal function. Consider reducing the dosage when administering sedatives. The dose of benzodiazepines, etomidate, and barbiturates should be reduced by as much as half because renal and liver function affects their clearance. Reduced clearance may lead to complications, such as hypotension and prolonged sedation. Lower dosages of ketamine should also be considered because of increased duration of action and reduced clearance in the elderly.
A surgical airway may also be difficult in the geriatric population because the elderly have decreased cervical mobility; looser skin on the neck; and a stiffer, smaller cricothyroid membrane. Needle cricothyrotomies and bougie-assisted techniques may aid in securing the airway.
Mechanical ventilation can be a life-saving strategy in patients with acute respiratory failure. However, mechanical ventilation does have the potential to aggravate and precipitate lung injury. Once intubated, ventilator settings should be adjusted depending on the cause of respiratory failure. In the elderly there are data to suggest that low-volume, low-pressure ventilation (lung-protective ventilation) is associated with better outcomes. Therefore, settings of 6 mL/kg and plateau pressure 30 cm H 2 O or less should be considered.
Circulation
Circulation should be assessed by heart rate, blood pressure, skin perfusion, and mental status. Vital signs should be trended carefully instead of relying on just the initial triage vital signs. Blood pressure is often difficult to obtain in the very ill. It has been suggested that if a patient has peripheral pulses, then the pressure is about 60 mm Hg and if femoral pulses are palpable then they have a blood pressure of at least 40 mm Hg. Failure to palpate a pulse does not automatically mean the patient is in arrest. There may be organized mechanical activity with an insufficient cardiac output to give meaningful circulation. The use of point-of-care ultrasound has allowed direct visualization of heart motion and can be used to guide therapy.
When determining how to resuscitate a geriatric patient, the goal is to optimize cardiac output while carefully monitoring cardiac activity. There are several physiologic changes that occur in the elderly that affect circulation during resuscitation. There is progressive stiffening of arteries and of the myocardium, which decreases cardiac output and can contribute to ventricular hypertrophy. In the geriatric patient when there is hemorrhage, infection, or pain, the normal response of tachycardia may be absent because the myocardium is less sensitive to catecholamines. Moreover, many of these patients take β-blockers and calcium channel blockers or other chronotropic drugs that further blunt the expected tachycardia that occurs with pain, hypovolemia, and shock. This in turn may lead to a delay in recognizing the severity of injury and therefore, the aggressive early treatment that may be necessary. Additionally, geriatric patients have relatively increased blood pressure in comparison with younger populations. When a physician gets a normal blood pressure in a geriatric patient they should consider the possibility that this may indicate hypoperfusion.
Detecting shock
Shock is a life-threatening state where end-organ and tissue perfusion is insufficient and there is inadequate oxygen for normal metabolism. Advanced shock, regardless of cause, has a mortality of up to 40%. Patients in shock who are sweating, tachycardic, and hypotensive are easy to spot. The geriatric population, for a variety of reasons, do not always manifest these obvious signs. Early signs and symptoms of shock including confusion, anxiety, and shortness of breath are often missed until they manifest as altered mental status, hypotension, tachycardia, oliguria, cool clammy skin, and metabolic acidosis. In isolation these clinical features are neither sensitive nor specific for the diagnosis of shock. Factors that make the identification of shock more difficult in the geriatric population include changes in the cardiovascular reflexes, medication, comorbidities, and unknown baseline blood pressure. Baseline blood pressure increases with age, so a normal blood pressure in a patient who usually is hypertensive can represent a shock state. The National Trauma Triage Protocol has recognized that systolic blood pressure less than 110 mm Hg may represent shock in those older than 65 years old. Automated blood pressure machines may overestimate the blood pressure in elderly patients because their arteries are stiff.
The elderly may also be less aware of their own illness because they have a 40% to 50% decreased perception of, and ventilatory response to, hypoxia and hypercapnia. Because of physiologic changes and increased dead space, a normal respiratory rate in elderly patients may be as high as 25 breaths per minute. A rate of greater than 25 breaths per minute may be the first sign of a lower respiratory tract infection, heart failure, or other disorder. Geriatric patients who have lost up to 35% of their intravascular volume are often not tachycardic, so the absence of tachycardia should not reassure the clinician about volume status or blood loss. By the time there are vital sign changes, the patient may be in extremis. Skin turgor testing and capillary refill have been shown to have a specificity of around 10% and thus are not useful. Orthostatic testing has been the subject of much debate. Studies measuring orthostatics from the supine to standing position showed reasonable specificity. However, it should be noted that a lack of mobility can make standing difficult for the elderly. In patients who are healthy and are not on vasoactive medication a pulse increase of 20 beats per minute has specificity for hypovolemia of 98%. In addition, a decrease in systolic blood pressure of 20 mm Hg or greater has a specificity of 97%. A shock index (heart rate/systolic blood pressure) of greater than or equal to 0.7 has a specificity for hypovolemia of 99%. Decreased urinary output should probably not be solely relied on as a sign of shock because it can be a late finding and may represent comorbid pathology instead of volume status.
Laboratory testing may aid in early identification of shock in the elderly. Point-of-care end tidal CO 2 has been shown to be an early predictor of metabolic acidosis and may be a way to quickly assess a patient’s status. Blood-urea-nitrogen and creatinine have been studied separately and as a ratio. Changes often reflect end-organ dysfunction, but in isolation do not always reliably predict shock or dehydration. Studies have shown that an abnormal lactate, pH and HCO3 3 in sepsis and trauma correlate with increased morbidity and mortality. Lactate in particular has been effectively used as a marker for shock. Lactate can be produced as a by-product of inadequate blood perfusion and as a marker of strained cellular metabolism. It can be used not only to help identify shock but also, with repeated levels, as a marker of the effectiveness of resuscitation. In septic shock, however, 10% to 15% of people are not lactate producers and acidosis is often a very late sign of shock. Ultrasound is being used more often as a rapid way to evaluate early shock. It aids in identification of shock and in categorizing the type of shock. Bedside assessment of the heart, inferior vena cava, Morison pouch, left upper quadrant, pelvis, aorta, and lungs is done quickly and effectively. The inferior vena cava can be evaluated to assess a patient’s volume status. Specifically, the inferior vena cava can be visualized and the collapsibility estimated. Patients can then be fluid resuscitated and their response seen in real time with repeat point-of-care ultrasound. Moreover, if the inferior vena cava is not collapsing with respiration it may indicate that the patient is not hypovolemic and that other treatments, such as inotropes, may need to be considered. In the end, there is no single test that perfectly predicts the development of shock, so a high index of suspicion should be maintained.
Even when shock is suspected, the type of shock can be cryptogenic. In any age group shock can be broken into hypovolemic, vasodilatory, cardiogenic, or obstructive ( Table 1 ). In the elderly there is a tendency to assign hypotension to either septic or cardiogenic shock, even in the absence of supporting data. Many of the clinical manifestations provide clues to the underlying cause and are primarily used to narrow the differential diagnosis so that empiric therapies can be administered in a timely fashion. However, early assignment of the probable cause of shock may be wrong in up to 30% of cases. A good history from family or review of nursing home records is essential. In the age of electronic medical records it is often possible to get a reasonable picture of a patient’s past medical history, an old electrocardiogram, and a medication list that may become invaluable as resuscitation progresses. The physical examination that reveals a dialysis shunt or automatic implantable cardioverter-defibrillator often makes a significant difference in treatment. In the geriatric population there is more overlap between the four standard categories of shock, which may have additive effects. A patient, for example, with poor cardiac function that becomes septic has elements of both types of shock contributing to the overall clinical picture. Bedside ultrasound evaluation with protocols, such as the RUSH examination ( Fig. 1 ), can reliably guide early therapy and assess improvement throughout the resuscitation. By evaluating the inferior vena cava, the heart, the lungs, the abdomen, and the aorta, 80% of shock can be correctly identified and treatment begun in the first 15 minutes of care. Frequent repeat examinations can quickly and accurately gauge response to therapy and further guide resuscitation.
