Exercise: Monitoring Devices

EXERCISE 3-6. MONITORING DEVICES

3-26. The complication of Swan-Ganz catheter placement in Case 3-26 (Figure 3-60) is

A.         malposition of the tip.

B.         pneumothorax.

C.         perforation.

D.         catheter coiling.

E.          catheter thrombosis.

3-27. The tip of the central venous catheter in Case 3-27 (Figure 3-61) is in the

·        inferior vena cava.

·        right ventricle.

·        azygous vein.

·        hemiazygous vein.

·        middle hepatic vein.

3-28. The malpositioned catheter in Case 3-28 (Figure3-62) is a(n)

A.   tracheostomy tube.

B.   intraaortic balloon pump.

C.   Swan-Ganz catheter.

D.   nasogastric tube.

E.   Blakemore tube.

3-29. The complication with the pacemaker shown in Case 3-29 (Figure 3-63) is

A.   right atrial lead dislodgement.

B.   right ventricular perforation.

C.   pneumothorax.

D.   right ventricular lead dislodgement.

E.   diaphragmatic pacing.

3-30. The catheter in Case 3-30 (Figure 3-64, arrow) is in the

A.         lung parenchyma.

B.         left superior vena cava.

C.         left upper lobe pulmonary vein.

D.         descending thoracic aorta.

E.          left pulmonary artery.

Radiographic Findings

3-26. The supine portable chest radiograph obtained after SG catheter placement in this case (Figure 3-60) is coiled within the right ventricle before it terminates in the proximal main pulmonary artery (D is the cor-rect answer to Question 3-26). This coiling of the catheter in the right ventricle may cause thrombosis or arrhythmia, and it is necessary to reposition this catheter.

3-27. The supine chest radiograph in this case (Figure 3-61) shows two turns in the course of the catheter after a difficult CVP placement. The catheter turns posteri-orly into the azygous vein and then descends on the right in the hemiazygous system (D is the correct answer to Question 3-27).

3-28. In this case (Figure 3-62), the chest radiograph ob-tained shows a nasogastric tube extending down the right main bronchus into the right lung (Figure 3-62, arrow) (D is the correct answer to Question 3-28).

3-29. In this case (Figure 3-63), the tip of the right ventric-ular pacemaker lead does not extend to the expected border of the myocardium. Usually a slight shoul-dering is encountered as the lead crosses the tricus-pid valve. In some cases, the right ventricular lead may be positioned higher along the interventricular septum and may take a more horizontal course. A vertical course, as in this case, indicates the tip is not lodged in the myocardium. This positioning results in a lack of normal pacing function. The right atrial lead is in an appropriate position. (D is the correct answer to Question 3-29.) midline to the superior vena cava, extends into the left superior pulmonary vein (C is the correct answer to Question 3-30). Because it is carrying blood returning from the pulmonary capillary bed, it is oxygenated like systemic arterial blood, but comes from a low-pressure system.

Discussion

As mentioned in the subsection on monitoring devices, a variety of catheters can be inserted into the heart and great vessels to monitor various hemo-dynamic parameters, particularly in the ICU setting. Table 3-3 lists the most common monitoring devices, and Table 3-4 shows the most common complications from place-ment of these devices. It is important to trace out and ac-count for each catheter individually. For instance, the nasogastric tube might have initially been mistaken for an ECG lead. The result of instilling fluid through this tube could have been disastrous. Even so, the result of this place-ment was a pneumothorax. We have reviewed the normal placement of catheters and some of the more common re-lated complications.