WBR0934

Author	PageAuthor::William J Gibson (Reviewed by Serge Korjian)
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Anatomy
Sub Category	SubCategory::Musculoskeletal/Rheumatology, SubCategory::Vascular
Prompt	[[Prompt::A 55-year-old smoker presents to his primary care physician for dyspnea. Physical examination reveals a right sided pleural effusion and chest-CT is concerning for malignancy. The physician is set to perform a thoracentesis, but must recall the positioning of the neurovascular bundle in the intercostal space. Which of the following represents the order of structures in the intercostal space from inferior to superior?]]
Answer A	AnswerA::Artery, Nerve, Vein
Answer A Explanation	AnswerAExp::The intercostal space contains the intercostal Vein, Artery, and Nerve (VAN) in that order from superior to inferior.
Answer B	AnswerB::Vein, Nerve, Artery
Answer B Explanation	AnswerBExp::The intercostal space contains the intercostal Vein, Artery, and Nerve (VAN) in that order from superior to inferior.
Answer C	AnswerC::Nerve, Artery, Vein
Answer C Explanation	AnswerCExp::The intercostal space contains the intercostal Vein, Artery, and Nerve (VAN) in that order from superior to inferior. Note that the question asks for the order from inferior to superior.
Answer D	AnswerD::Nerve, Vein, Artery
Answer D Explanation	AnswerDExp::The intercostal space contains the intercostal Vein, Artery, and Nerve (VAN) in that order from superior to inferior.
Answer E	AnswerE::Vein, Artery, Nerve
Answer E Explanation	AnswerEExp::The intercostal space contains the intercostal Vein, Artery, and Nerve (VAN) in that order from superior to inferior.
Right Answer	RightAnswer::C
Explanation	[[Explanation::Lung tumors are a common cause of pleural effusions. Thoracentesis is a procedure in which a needle is inserted through the intercostal space to aspirate excess fluid or air from the lung. The neurovascular bundle runs high in the intercostal space in the intercostal groove and is composed of the vein, artery and nerve (VAN) in that order from superior to inferior. When performing thoracentesis, the physician must insert the needle immediately superior to the bottom rib of the intercostal space to avoid injuring structures in the neurovascular bundle. This space is not free of neurovascular structures, but the existing ones are collaterals that are not as essential as the main intercostal artery and vein. Educational Objective: The intercostal space contains the Vein, Artery, and Nerve (VAN) in that order from superior to inferior. References: Moore KL, Agur AM, (II) AF. Essential Clinical Anatomy. Lippincott Williams & Wilkins; 2014.]]
Approved	Approved::Yes
Keyword	WBRKeyword::Vasculature, WBRKeyword::Nerve, WBRKeyword::Artery, WBRKeyword::Vein, WBRKeyword::Intercostal, WBRKeyword::Thoracic, WBRKeyword::Thoracic anatomy, WBRKeyword::Thorax, WBRKeyword::Rib, WBRKeyword::Ribs, WBRKeyword::Lungs, WBRKeyword::Lung, WBRKeyword::Pleural effusion, WBRKeyword::Pleurocentesis, WBRKeyword::Anatomy
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Order in Linked Questions	LinkedOrder::