Chapter 321 - Approach to the Patient with Critical Illness Flashcards
Critical care physicians often must redirect the goals of care from resuscitation and cure to comfort when the resolution of an underlying illness is not possible.
True or False?
True.
Severity-of-illness scoring systems are usefull tools to assess individual patient outcomes.
True or False?
False.
“Although these scoring systems have been validated as tools to assess populations of critically ill patients, their utility in predicting individual patient outcomes is not clear.”
Name the main usefulness of severity-of-illness (SOI) scoring systems. How were these scales obtained?
“SOI scoring systems are important for defining populations of critically ill patients. Such systematic scoring allows effective comparison of groups of patients enrolled in clinical trials. In verifying a purported benefit of therapy, investigators must be confident that different groups involved in a clinical trial have similar illness severities. SOI scores are also useful in guiding hospital administative policies, directing the allocation of resources such as nursing and ancillary care and assisting in assessments of quality of ICU care over time.”
“All existing SOI scoring systems are derived from patients who have already been admited to the ICU.”
Which Severity-of-Illness Scoring system is most commonly used in intensive unit cares in North America?
APACHE II.
Name the variables measured for APACHE II score calculation.
“Age, type of ICU admission (after elective surgery vs nonsurgical or after emergency surgery), chronic health problems, and 12 physiologic variables (the worst values for each in the first 24 h after ICU admission) are used to derive a score).”
The 12 physiologic variables include: rectal temperature, mean blood pressure, heart rate, respiratory rate, arterial pH, oxygenation, serum sodium, serum potassium, serum creatinine, hematocrit, white blood cell count and Glasgow Coma Score.
Which year was SAPS 3 developped?
2005
Name the differences between SAPS and APACHE.
“The SAPS II score, used more frequently in Europe than in the United States, was derived in a manner similar to the APACHE score. This score is not disease specific but rather incorporates these underlying disease variables: AIDS, metastatic cancer, and hematologic malignancy.”
There is no shock without hypotension.
True or False?
False.
How does one clinically differentiate diminished from increased cardiac output?
“Clinical evidence of dimished cardiac output includes a narrow pulse pressure - a marker that correlates with stroke volume - and cool extremities with delayed capillary refill. Signs of increased cardiac output include a widened pulse pressure (particularly with a reduced diastolic pressure), warm extremities with bounding pulses, and rapid capillary refill.”
How do you define shock and which clinical signs would you look for if you suspect that a patient might have a shock diagnosis?
“shock, a common condition necessitating ICU admission or occurring in the course of critical care, is defined by the presence of multisystem end-organ hypoperfusion. Clinical indicators include reduced mean arterial pressure (MAP), tachycardia, tachypnea, cool skin and extremities, acute altered mental status, and oliguria.”
Since mean arterial pressure is a product of cardiac output and systemic vascular resistance (SVR), if you find clinical signs of reduced cardiac output and hypotension, what might one infer as the cause of hypotension?
Reduced SVR.
Which of the following is the best predictor of fluid responsiveness: (A) static measurement of right atrial pressure; (B) change in right atrial pressure with spontaneous respiration.
B.
Patients with hypovolemic shock may also manifest larger changes in pulse pressure as a function of respiration during mechanical ventilation.
True or False?
True.
Which signs would you expect to find in a hypotensive patient with cardiac dysfunction?
“A hypotensive patient with increased intravascular volume and cardiac dysfunction may have an S3 and/or S4 gallops on examination, increased jugular venous pressure, extremity edema, and crackles on lung auscultation.”
In a patient with cardiogenic shock suspicion, which imagiologic signs would you expect to find on x-ray and electrocardiography?
“The chest x-ray may show cardiomegaly, widening of the vascular pedicle, Kerley B lines, and pulmonary edema. Chest pain and electrocardiographic changes consistent with ischemia may be note.”
What is the most common cause of high-cardiac-output hypotension?
Sepsis.
Name causes of high-cardiac-output hypotension other than sepsis.
“Other causes include liver failure, severe pancreatitis, burns and other trauma that elicit the systemic inflammatory response syndrome (SIRS), anaphylaxis, thyrotoxicosis, and peripheral arteriovenous shunts.”
Shock has only one category as its cause.
True or False?
False.
Which are the main categories of shock?
Hypovolemic, cardiogenic and high-cardiac-output with decreased systemic vascular resistance (high-output hypotension).
Septic and cardiogenic shock may have survival improvement if early resuscitation is conducted.
True or False?
True.
“The goal of early resuscitation is to reestablish adequate tissue perfusion and thus to prevent or minimize end-organ injury.”
Name the causes of acute hypoxemic respiratory failure.
“Acute hypoxemic respiratory failure may occur in patients with cardiogenic shock and pulmonary edema as well as in those who are in septic shock with pneumonia or acute respiratory distress syndrome (ARDS).”
What kind of pH disturbance would you expect to find in a patient with shock?
Acute metabolic (often lactic) acidosis.
Explain the pathophysiollogy for increased ventilatory load and consequent ventilatory failure in patients with cardiogenic shock.
Cardiogenic shock may lead to pulmonary edema and incrased ventilatory load. Shock with hypoperfusion (of any cause) may also include decreased vascularization of respiratory muscles and consequent lactic acid production.
“Lactic acid production from inefficient respiratory muscle activity presents an additional ventilatory load.”
The percentage of cardiac output dedicated to respiratory muscles may increasetenfold or more in shock patients.
True or False?
True.
What are the indicators of respiratory distress?
“Patients demonstrate respiratory distress by an inability to speak full sentences, accessory use of respiratory muscles, paradoxical abdominal muscle activity, extreme tachypnea (>40 breaths/min), and decrasing respiratory rate despite an increasing drive to breathe.”
Mechanical ventilation reduces median arterial pressure (MAP).
True or False?
Argue your answer.
True.
“ With the institution of mechanical ventilation for shock, further declines in MAP are frequently seen. The reasons include impeded venous return from positive-pressure ventilation, reduced endogenous catecholamine secretion once the stress associated with respiratory failure abates, and the actions of drugs used to facilitate endotracheal intubation (e.g., propofol, opiates).”
Name two major goals of mechanical ventilation.
“Mechanical ventilation may relieve the work of breathing and allow redistribution of a limited cardiac output to other vital organs.”
How many patients might need mechanical ventilatory support in UCI?
≥75% in some UCIs.
