FIGURE 29.1 Patient with right upper lobe collapse and associated S-sign of Golden as demonstrated by the reverse S shape at the inferolateral border of the right upper lobe (arrow).
Pulmonary Edema
Massive fluid resuscitation, burns, opiate overdose, cardiac or traumatic brain injury and a multitude of other etiologies can result in volume overload in the ICU patient. The most common pattern is a “batwing” appearance of perihilar airspace opacification, with bilateral pleural effusions (Fig. 29.7). Patients with cardiogenic pulmonary edema secondary to heart failure often have accompanying enlargement of the heart chambers or stigmata of recent or prior cardiac event or surgery. Diffuse bilateral parenchymal opacification may also be seen in alveolar edema (3). Cardiovascular status of the patient, clinical history, and volume status are helpful in differentiating edema from infection or ARDS.
Pneumothorax
The critically ill patient is most often in the recumbent position, which can make the recognition of a pneumothorax difficult. A pneumothorax in the recumbent position may collect anteriorly, at the lung base, leading to the deep sulcus sign. The deep sulcus sign is the lucency at the lung base caused by air trapped in the most anterior portion of the pleural space in a recumbent patient (Fig. 29.8). Careful interrogation of a radiograph can also show the more easily recognized pleural reflection separate from the lateral thorax margin (Fig. 29.9). Pneumothorax in the ICU is often a complication of barotrauma, vascular access, or pleural drainage (5).
Support Lines and Tubes
The critical status of the ICU patient often requires the use of multiple support lines and tubes to monitor and administer therapy. Appropriate positioning after initial positioning should be performed with chest radiography to verify appropriate placement and to exclude complications such as atelectasis, pneumothorax, or hematoma.
Endotracheal Tube
The endotracheal tube (ET), is preferably located in the trachea 2 to 4 cm above the carina or projecting at the level of the clavicular heads (Fig. 29.10) (3,6). An ET that has been advanced too far caudally into the airway may enter one of the two main bronchi and result in lobar collapse and atelectasis of the contralateral lobe (see Fig. 29.2).
Central Catheter Placement
Central venous catheters used for fluid, antibiotic administration, or parenteral nutrition can be placed into the subclavian or jugular veins with its tip most preferably projecting into the superior vena cava (SVC). Catheters that are advanced too far into the right heart or even into the inferior vena cava should be retracted, leaving the tip in the SVC. Some central venous access catheters, notably dialysis catheters, are designed to terminate in the right heart (7). The apex of the lung is in close proximity to the puncture site for a subclavian approach and thus is at risk for a pneumothorax. A peripherally inserted central catheter (PICC) is a long intravenous catheter usually advanced from a peripheral upper extremity vein with optimal positioning of its tip in the SVC (Fig. 29.11).
A pulmonary artery catheter (PAC) is usually placed via an introducer into the subclavian or jugular vein and advanced into either the right (most commonly) or left pulmonary artery to facilitate its use as a monitor of cardiac function. The PAC ideally should be positioned in the proximal right or left pulmonary artery (Fig. 29.12) (3). If the catheter is advanced too far distally, the balloon tip can cause pulmonary infarction. If placed too proximal, as in the right ventricle, the PAC could trigger dysrhythmias and result in potential inaccurate measurements (8).