Cardiorenal

Question 1

Question

Answer 1

E. Lactated Ringer Solution

This patient with fever, cough, and radiologic evidence of consolidation in the right lower lung has pneumonia. Her tachycardia, hypotension, and confusion (evidence of end-organ hypoperfusion) are most likely due to septic shock, which is characterized by increased permeability of the vascular endothelium with leakage of intravascular fluid into the extravascular space.

In the management of septic shock, rapid restoration of intravascular volume and adequate end-organ perfusion is critical. This is best accomplished with the administration of boluses of isotonic crystalloid in the form of 0.9% (normal) saline or lactated Ringer solution through large-bore, peripheral intravenous catheters. These solutions are ideal for volume resuscitation because they have osmolarity very close to the normal osmolarity of the blood (~285 mOsm/kg H2O), while the sodium and chloride ions help retain the fluid in the extracellular space.

Prompt initiation of appropriate empiric antibiotic therapy is also critical in the management of septic shock.

(Choices A and C) 0.45% (half-normal) saline is hypotonic; 5% dextrose in 0.45% saline is hypertonic initially but becomes hypotonic following infusion because the dextrose is rapidly metabolized. These hypotonic solutions are often used at low infusion rates for patients with a deficiency of free water (ie, hypernatremia) or for maintenance hydration. However, they are not effective for rapid volume resuscitation because the low osmolarity causes much of the fluid volume to shift into the intracellular space following infusion.

(Choice B) Infusion of 3% (hypertonic) saline can lead to rapid fluid-shifting from the intracellular to the extracellular space with potentially devasting consequences (eg, osmotic demyelination syndrome); therefore, 3% saline is not appropriate for rapid volume resuscitation. It is appropriate for careful use in patients with severe symptomatic hyponatremia.

(Choice D) Albumin solution is an isotonic colloid solution that can be used for rapid volume resuscitation. However, it is less preferred due to high cost and limited availability compared to isotonic crystalloid.

(Choice F) Sodium bicarbonate solutions can have variable tonicity and are typically used at low infusion rates for patients with severe metabolic acidosis. These solutions are generally not used for rapid volume resuscitation.

Educational objective:
The initial management of septic shock requires rapid fluid resuscitation to replace intravascular volume and restore adequate end-organ perfusion. This is best accomplished with intravenous boluses of isotonic crystalloid in the form of 0.9% (normal) saline or lactated Ringer solution because these solutions remain in the extracellular space.

Question 2

.9% saline use

Answer 2

volume resuscitation (eg hypovolemia and shock)

Question 3

Lactated Ringer solution use

Answer 3

volume resuscitation (eg hypovolemia and shock)

Question 4

Albumiun solution use

Answer 4

Volume replacement

Tx of Spontaneous bacterial peritonitis or hepatorenal syndrome

Question 5

Dextrose 5% use

Answer 5

Free water deficit

Question 6

0.45% (half-normal) saline

Answer 6

Free water deficit (hypernatremia)

Question 7

Dextrose 5% in 0.45 (half-normal) saline

Answer 7

Maintenance hydration

Question 8

3% (hypertonic saline) use

Answer 8

Severe symptomatic hyponatremia