During a pericardiocentesis performed via the subxiphoid (epigastric) route with the needle directed toward the left shoulder, which anatomical space is entered and what is the fluid's location?

• A Oblique pericardial sinus, between the left pulmonary veins and IVC
• B The general pericardial cavity (parietal pericardium to visceral pericardium/epicardium space) ✓
• C Transverse pericardial sinus, between the great arteries and veins
• D Left pleural cavity

Explanation

Pericardiocentesis drains fluid from the pericardial cavity — the potential space between the parietal layer of serous pericardium (lining the fibrous pericardium) and the visceral layer (epicardium covering the heart surface). Normally, 15-50 mL of pericardial fluid lubricates cardiac movement. In pericardial effusion (hemopericardium, tamponade), fluid accumulates here. The subxiphoid approach (needle directed 45° superiorly toward left shoulder) avoids lung injury and is the safest route. The transverse sinus is a passage posterior to the great arteries and anterior to the atria/pulmonary veins, formed during cardiac looping; the oblique sinus is a blind pocket posterior to the left atrium.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.