1. Correct Answer: B. Bronchodilators and steroids

Rationale: Figure 74.1 shows a lung point sign: the point at which the lung (visceral pleura) begins to separate from the chest wall (parietal pleura). Initially thought to be pathognomonic for pneumothorax, a lung point sign can also be seen in patients with blebs from COPD or other disease processes in which the lung is adherent to the chest wall (e.g., asbestosis). This is confirmed by the presence of a lung pulse, that is, movement of the heart transmitted to and sensed at the pleural space, which can be seen on the right side of the image. The patient in this question is having a COPD exacerbation, so choice B is correct. Based on the vital signs, the patient is not in extremis, so choice A is incorrect. In a stable patient with COPD, you should obtain further imaging (computed tomography [CT] scan) before placing a chest tube, so choice C is incorrect. A small pleural effusion is not likely to cause significant dyspnea, so choice D is incorrect.

1. Aziz SG, Patel BB, Ie SR, Rubio ER. The lung point sign, not pathognomonic of a pneumothorax. Ultrasound Q. 2016;32(3):277-279.

2. Correct Answer: A. RED arrow

Rationale: Figure 74.8A shows a longitudinal view of the common femoral artery and its bifurcation into the superficial femoral artery and the deep femoral artery. Figure 74.8B shows a transverse view of the superficial femoral artery, the deep femoral artery, and the common femoral vein at the junction with the greater saphenous vein. The ideal location for femoral artery puncture is in the common femoral artery proximal to the bifurcation (choice A). This area is usually above the middle third of the femoral head (not pictured here). Puncture into the superficial femoral artery (choices B and C) increases the likelihood of unsuccessful cannula placement and increases the incidence of retroperitoneal bleeding and pseudoaneurysms. Choice D is the femoral vein. See Figure 74.8 for additional details.

1. Turi ZG. Ending “poke until you get a gusher”: part II-the evidence based approach to vascular access revisited. Catheter Cardiovasc Interv. 2017;89(7):1185-1192.

3. Correct Answer: B. Figure 74.3B

Rationale: Figure 74.3B shows pulsed-wave Doppler tracing of a vein, evidenced by the flow away from the probe during systole and diastole at a relatively slow velocity. Figure 74.3A shows pulsed-wave Doppler of an artery, evidenced by flow only during systole at a relatively faster velocity. Figure 74.3C shows M-mode without a corresponding B-mode image. M-mode alone is not used to identify a specific vessel. Since there is no B-mode image with the M-mode tracing, it would be difficult to differentiate an artery from a vein. Figure 74.3D shows color Doppler with flow going away and coming toward the probe. Based on this limited information, it would be difficult to differentiate the artery from the vein, although real-time visualization may help identify the appropriate vessel.

1. Troianos CA, Hartman GS, Glas KE, et al. Guidelines for performing ultrasound guided vascular cannulation: recommendations of the American Society of Echocardiography and the Society of Cardiovascular Anesthesiologists. J Am Soc Echocardiogr. 2011;24:1291-1318.

4. Correct Answer: D. Finding an alternative vessel is recommended.

Rationale: Figure 74.4 shows a thrombus within the internal jugular vein. Whenever a thrombus is visualized on ultrasound, it is recommended to find an alternative vessel for central line placement, so choice D is correct. Central line placement in this vessel would increase the risk of dislodging part or all of the thrombus, leading to a pulmonary embolism.

1. Saugel B, Scheeren TWL, Teboul JL. Ultrasound-guided central venous catheter placement: a structured review and recommendations for clinical practice. Crit Care. 2017;21(1):225.

2. Silverberg MJ, Kory P. Intensive care ultrasound: II. Central vascular access and venous diagnostic ultrasound. Ann Am Thorac Soc. 2013;10(5):549-556.