OSCE Procedural Skills 2 — Questions and Answers
Question 1: When performing a lumbar puncture, at which intervertebral space should the needle be inserted in an adult?
- L1-L2
- L2-L3
- L3-L4 (Correct answer)
- L5-S1
Correct answer: L3-L4
L3-L4 (or L4-L5) is preferred because the spinal cord ends at L1-L2, minimizing risk of cord injury.
Question 2: Which landmark is used to identify the correct level for lumbar puncture?
- Inferior angle of the scapula
- Posterior superior iliac spine (Tuffier's line) (Correct answer)
- Iliac crest at the umbilicus level
- Spinous process of T12
Correct answer: Posterior superior iliac spine (Tuffier's line)
Tuffier's line connects the posterior superior iliac spines and typically intersects at the L4 spinous process.
Question 3: During urinary catheterization of a male patient, resistance is felt at the external sphincter. What is the most appropriate next step?
- Apply firm continuous pressure to force the catheter through
- Withdraw the catheter and select a smaller size
- Ask the patient to relax and take deep breaths, then gently advance (Correct answer)
- Inflate the balloon to dilate the sphincter
Correct answer: Ask the patient to relax and take deep breaths, then gently advance
Having the patient relax the sphincter voluntarily by deep breathing allows gentle advancement without traumatizing the urethra.
Question 4: What is the correct sequence for donning sterile gloves using the open gloving technique?
- Pick up dominant-hand glove by the cuff, don it, then use gloved hand to slide under the cuff of the second glove (Correct answer)
- Pick up non-dominant glove first, then use bare fingers to pick up dominant-hand glove by its outer surface
- Open packaging with unsterile hands, then touch only the inner surfaces
- Don gloves in any order as long as hands are scrubbed
Correct answer: Pick up dominant-hand glove by the cuff, don it, then use gloved hand to slide under the cuff of the second glove
The dominant hand glove is donned first by grasping only the folded cuff, then the sterile gloved hand slides under the second glove's cuff.
Question 5: A patient requires nasogastric tube insertion. After passing the tube, how do you confirm correct gastric placement at the bedside?
- Listening for air sounds over the epigastrium while injecting 10–20 mL of air with a syringe (Correct answer)
- Asking the patient to speak normally
- Checking that the tube length at the nostril matches pre-measured distance
- Observing for coughing only
Correct answer: Listening for air sounds over the epigastrium while injecting 10–20 mL of air with a syringe
Auscultation of a 'whoosh' over the epigastrium after air injection is a standard bedside check, though radiographic confirmation is gold standard.
Question 6: When inserting a peripheral IV cannula, once blood flashback is seen, what is the next correct step?
- Immediately remove the needle and discard
- Advance the needle 1–2 mm further, then slide the cannula off the needle into the vein (Correct answer)
- Inflate a tourniquet more tightly before advancing
- Apply direct pressure proximal to the insertion site
Correct answer: Advance the needle 1–2 mm further, then slide the cannula off the needle into the vein
Advancing slightly ensures the cannula tip is within the vessel lumen before threading the plastic cannula over the needle.
Question 7: In a pelvic examination OSCE station, after inserting the speculum to visualize the cervix, what is the correct direction to open the speculum blades?
- Laterally (side to side)
- Vertically (up and down) (Correct answer)
- Diagonally at 45 degrees
- Rotate 90 degrees before opening
Correct answer: Vertically (up and down)
The speculum blades are opened in the vertical (anterior-posterior) plane to separate the anterior and posterior vaginal walls and expose the cervix.
OSCE Procedural Skills 2
When performing a lumbar puncture, at which intervertebral space should the needle be inserted in an adult?