Radiographic Imaging and Bedside Ultrasound

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.

FIGURE 29.2 Placement of the endotracheal tube into the right mainstem bronchus (*arrow*), a not uncommon complication secondary to the more vertical orientation of the right main bronchus as compared to the left (carina; *dashed line*). There is associated atelectasis of the left lung and slight leftward cardiomediastinal shift.

FIGURE 29.3 Patient with complete opacification of the right hemithorax. There is ipsilateral mediastinal shift as would be expected with atelectasis (*arrows*).

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).

FIGURE 29.4 Right greater than left bilateral pleural effusions in a supine patient on portable anterior–posterior examination shows blunting of the costophrenic angles and obscuration of the hemidiaphragms.

FIGURE 29.5 Airspace opacity with branching linear lucencies represents outlining of bronchi by surrounding alveolar consolidation and air bronchograms (*arrow*). Findings are concerning for lobar pneumonia in the right middle lobe.

FIGURE 29.6 Intubated patient indicating respiratory failure. There are diffuse airspace opacities such as can be seen in the setting of adult respiratory distress syndrome.

FIGURE 29.7 Batwing or perihilar opacities in a patient with cardiomegaly and bilateral pleural effusions; the latter is indicated by blunting of the costophrenic angles. This finding indicates pulmonary edema.

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).

FIGURE 29.8 Chest radiograph demonstrates right basilar pneumothorax with deep sulcus sign (*curved arrow*). Note the large medially displayed right lower lung opacity caused by pneumonia (*straight arrow*).

FIGURE 29.9 Subtle pneumothorax after left-sided thoracentesis (*arrow*). Note the thin radiodense pleural reflection.

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).