ABSITE - Critical Care EXAM QUESTIONS WITH ACTUAL CORRECT VERIFIED
ANSWERS ALREADY GRADED A+ NEWEST EDITION REVISED BY EXPERTS
All are potential causes of cardiogenic shock except:
- Myocardial infarction.
- Pericardial tamponade.
- Tension pneumothorax.
- Cardiac arrhythmias.
- Excessive preload. - ANSWERS-Excessive preload.
(Excessive preload is typically not a cause of cardiogenic shock, but is a result of cardiogenic shock.)
A 60-year-old man has an arterial PO of 60 mm Hg when the calculated alveolar PO is 94 mm Hg. This
difference is most commonly due to - ANSWERS-a ventilation-perfusion mismatch
oxygen delivery and consumption - ANSWERS-- Under normal circumstances, approximately 20% to 30%
of the oxygen delivered to the capillary bed is extracted by the tissues.
- In conditions of decreased delivery of oxygen, tissues are capable of extracting up to 50% to 60% of the
oxygen content in the capillary blood.
- When cellular oxygen supply does not meet demand, anaerobic respiration results.
(The variables in the equation for the delivery of oxygen are cardiac output, hemoglobin level, oxygen
saturation of hemoglobin, and the partial pressure of oxygen dissolved in blood. Increases in the first
three variables all yield significant increases in the total amount of oxygen carried by blood. The partial
pressure of oxygen is multiplied by a factor of 0.003, however, and therefore has a miniscule
contribution to the total oxygen content.)
Dopamine at doses of 5 to 10 μg/kg/min - ANSWERS-has a largely inotropic action profile
(Dopamine has a dose-dependent action profile. At 3 to 5 μg/kg/min, its actions are largely to increase
renal blood flow. At doses of 5 to 10 μg/kg/min, it largely acts to stimulate myocardial β receptors and
,has an inotropic effect. At doses greater than 10 μg/kg/min, it stimulates α receptors and has a
chronotropic effect.)
As oxygen delivery increases on the flat horizontal portion of the oxygen consumption-delivery curve -
ANSWERS-Oxygen consumption remains the same
(On the flat horizontal portion of the oxygen consumption-delivery curve, oxygen delivery meets cellular
demand of oxygen; as oxygen delivery increases, oxygen consumption remains the same.)
Most disorganized ventricular arrhythmias (frequent PVCs, ventricular fibrillation) are caused by -
ANSWERS-Metabolic derangements.
(Most disorganized ventricular arrhythmias are caused by some sort of metabolic derangement such as
ischemia or magnesium or potassium deficiencies. These abnormalities are not well treated by
antiarrhythmic medications.)
The best management for a patient with a posterior knee dislocation - ANSWERS-Arteriogram.
(The patient may have fairly normal pulses and still have an intimal injury of the popliteal artery that is
similar to the intimal disruption that can be seen in aortic isthmus injury.)
the possible etiologies of multiorgan failure - ANSWERS-- Anticytokine antibodies have shown
therapeutic promise in animal studies.
- Evidence has shown that intestinal mucosa is made permeable by sepsis.
- The "two-hit" hypothesis postulates that after mounting an appropriate response to some physiologic
insult, the patient is left with a primed immune system which manifests an exaggerated immune
response to a second challenge.
- The early stages after injury actually appear to consist of an immediate proinflammatory state as the
organism tries to address the physiologic insult. When properly modulated, this is an appropriate
function. When overexpressed, this proinflammatory state leads to the systemic inflammatory response
syndrome. Later, anti-inflammatory and immunosuppressive mechanisms are brought into play to bring
the organism back to homeostasis. If overmanifested, they can lead to a relative generalized
immunosuppression and late incidents of sepsis or multiorgan failure.
compensatory mechanisms in shock - ANSWERS-Antidiuretic hormone causes the reabsorption of free
water by the kidney and has vasoconstrictive properties.
(Antidiuretic hormone is released from the posterior pituitary where it stimulates free water retention
by the kidney and acts as a powerful vasoconstrictor.)
,A 71-year-old man with colon cancer is in the intensive care unit following a left hemicolectomy. His
blood pressure is 72/38 mm Hg, pulse rate is 114/min, respiratory rate is 23/min, and oxygen saturation
is 94% on 2 L of oxygen by nasal cannulae. A pulmonary artery catheter shows a central venous pressure
of 8 cm H O, a pulmonary artery pressure of 22/8 mm Hg, a pulmonary artery wedge pressure of 6 mm
Hg, and a cardiac output of 3.4 L/min. The next step in management should be the intravenous
administration of - ANSWERS-a fluid bolus
pulmonary artery catheters - ANSWERS-Allow accurate approximation of left atrial pressure.
The magnitude of a left-to-right shunt in the presence of an ASD is determined by - ANSWERS-Difference
in compliance between left and right ventricles.
(The blood will tend to fill the more compliant ventricle which will usually be the right, until chronic
pulmonary hypertension yields right ventricular hypertrophy.)
Compared to conventional ventilation (endotracheal intubation), noninvasive ventilation (mask,
continuous positive airway pressure) is - ANSWERS-contraindicated in hemodynamically unstable
patients
According to the American College of Chest Physicians/Society of Critical Care Medicine Consensus
Conference, which of the following are not part of the diagnostic criteria for sepsis? - ANSWERS-
Hypotension defined as a systolic blood pressure less than 90 mm Hg.
(Sepsis is defined as bacteriologic evidence of infection superimposed on a clinical picture of SIRS.
According to the ACCP/SCCM, by definition these patients are hemodynamically stable. If they should
become hemodynamically unstable (defined as a systolic blood pressure <90 mm Hg), the name for the
condition changes to "severe sepsis.")
SIRS - ANSWERS-- Temperature greater than 38°C or less than 36°C.
- Heart rate greater than 90 bpm.
- Respiratory rate greater than 22 bpm
- White blood cell count greater than 12,000 or less than 4,000 and greater than 10% bands.
abdominal compartment syndrome - ANSWERS-Once diagnosed, treatment consists of reopening the
abdomen including doing so at the bedside if necessary.
, (The presence of an abdominal compartment syndrome requires decompression of the abdomen. If the
patient is too unstable to be transported to the operating room, the abdomen should be promptly
reopened at the bedside.)
carotid bruit - ANSWERS-a marker for generalized atherosclerosis
(In fact, studies have shown that a carotid bruit is a risk factor for coronary artery disease and future
myocardial infarction.)
alveolar ventilation - ANSWERS-The alveolar gas equation characterizes the potential for oxygen uptake
and carbon dioxide removal.
(Tachypnea at a given minute ventilation increases anatomic dead-space ventilation, not alveolar
ventilation. Minute ventilation is the volume of gas that is inspired and expired at the nasopharynx and is
different than that occurring at the alveolus by the anatomic dead-space volume. Although arterial Pco is
proportional to alveolar ventilation, arterial Po is not as it may be affected by physiologic shunting,
diffusion block, and so on. The RQ is constant under normal physiological conditions at ± 0.8; however, it
may change substantially under conditions such as anaerobic metabolism, overfeeding, and so on.
Because the alveolar gas equation characterizes the partial pressures of individual gases within the
alveolus, which in turn determine the individual gradients for diffusion, the equation does characterize
the potential for oxygen/carbon dioxide exchange. )
the following may constitute the physiological dead space of the respiratory system - ANSWERS--
Emphysematous lung.
- Lung involved with a pulmonary embolus.
- Proximal two thirds subsegmental bronchi.
- Zone one alveoli.
(The acinus, comprising the last seven generations of dividing subsegmental bronchi, is composed of
respiratory bronchioles, alveolar ducts, and alveolar air sacs surrounded by the pulmonary capillary
network and constitute the respiratory surface of the lung for gaseous exchange. All bronchi proximal to
these constitute conducting airways not involved in gaseous exchange and, therefore, constitute
anatomic dead space. Furthermore, nonperfused alveoli, such as may occur due to gravitational effects
with zone one alveoli and with certain pathologic conditions such as emphysema and PTE constitute
alveolar dead space. Each of these contributes to the physiological dead space.)
the pericardial space - ANSWERS-Allows access to all vessels entering and leaving the heart.
