VABC Pharmacology & Infusion Therapy 2 — Questions and Answers
Question 1: Which anticoagulant is most commonly used for locking central venous catheters to maintain patency between infusions?
- Warfarin
- Heparin (Correct answer)
- Alteplase
- Bivalirudin
Correct answer: Heparin
Heparin is the most widely used catheter lock solution due to its anticoagulant properties that prevent thrombus formation in the catheter lumen.
Question 2: A patient's IV site exhibits erythema, warmth, induration, and a palpable cord along the vein path. These findings are most consistent with:
- Extravasation
- Infiltration
- Phlebitis (Correct answer)
- Hematoma formation
Correct answer: Phlebitis
Phlebitis presents with erythema, warmth, pain, and a palpable venous cord caused by inflammation of the vein wall.
Question 3: Which medication preparation would be CONTRAINDICATED for peripheral IV administration due to its osmolarity?
- 0.9% Normal Saline (308 mOsm/L)
- Lactated Ringer's Solution (273 mOsm/L)
- Potassium Chloride 40 mEq in 100 mL (~800 mOsm/L) (Correct answer)
- 5% Dextrose in Water (252 mOsm/L)
Correct answer: Potassium Chloride 40 mEq in 100 mL (~800 mOsm/L)
KCl 40 mEq in 100 mL creates an osmolarity of approximately 800 mOsm/L, exceeding the peripheral threshold and carrying significant risk of phlebitis and cardiac arrhythmia if administered too rapidly.
Question 4: The 'SASH' flushing protocol for central venous catheters stands for which sequence?
- Sterile water, Antibiotic, Saline, Heparin
- Saline, Administer medication, Saline, Heparin (Correct answer)
- Sodium chloride, Aspiration, Saline, Hold
- Saline, Aspirate, Sterilize, Heparin
Correct answer: Saline, Administer medication, Saline, Heparin
SASH = Saline flush, Administer the medication, Saline flush, Heparin lock — a standardized protocol ensuring medication delivery and catheter patency.
Question 5: What is the maximum recommended infusion rate for potassium chloride (KCl) administered via a peripheral IV route?
- 5 mEq/hour
- 10 mEq/hour (Correct answer)
- 20 mEq/hour
- 40 mEq/hour
Correct answer: 10 mEq/hour
The standard maximum peripheral KCl infusion rate is 10 mEq/hour to prevent phlebitis, pain, and cardiac arrhythmias; higher rates require central venous access.
Question 6: Cytotoxic drugs that cause blistering, tissue necrosis, and permanent injury upon extravasation are classified as:
- Irritants
- Vesicants (Correct answer)
- Sensitizers
- Sclerosants
Correct answer: Vesicants
Vesicants are drugs capable of causing blistering and tissue destruction upon extravasation, requiring immediate intervention to minimize tissue damage.
Question 7: What is the key distinction between infiltration and extravasation?
- Infiltration involves air; extravasation involves blood
- Infiltration is leakage of non-vesicant solution; extravasation is leakage of a vesicant or blood product (Correct answer)
- Infiltration occurs centrally; extravasation occurs peripherally
- Infiltration causes necrosis; extravasation causes phlebitis
Correct answer: Infiltration is leakage of non-vesicant solution; extravasation is leakage of a vesicant or blood product
Infiltration refers to the leakage of non-vesicant solutions into surrounding tissue, while extravasation specifically involves vesicants or blood products that can cause serious tissue damage.
VABC Pharmacology & Infusion Therapy 2
Which anticoagulant is most commonly used for locking central venous catheters to maintain patency between infusions?