On-Call Radiology

Particularly important to consider in ICU patients who are receiving positive end-expiratory pressure(PEEP). 5-15% of those on mechanical ventilation can develop extrapulmonary air (PTX, pneumomediastinum, subpleural air).

12-15% of patients will have malpositioning of the ETT on initial placement.

The tip of the ETT should be positioned 4-6 cm above the carina with the patient’s neck in a neutralposition.

Flexion of the neck = movement of ETT inferiorly (towards carina) on CXR and vice versa.

A CVC catheter tip should ideally be located at the cavoatrial junction.

A PICC line catheter tip should be located the inferior aspect of the SVC.

Common indications for NG tubes include decompression of the stomach (e.g. for ileus or bowel obstruction), medication administration, or enteral nutrition. Obstruction of the esophagus may occur if the NG tube is not inserted far enough into the stomach; at least 10 cm of the tip should be within the stomach.

NG tubes are contraindicated in esophageal strictures (risk of perforation) or basilar skull fracture or facial fracture (risk of intracranial misplacement), but safe in patients with varices.

The two most common types of NG tubes you will encounter are Salem Sump (suction tube; stiffer, has two lumens for aspiration and irrigation/medication delivery/feeding, more commonly used for decompression but can be irritating), and dobhoff (flexible feeding tube; more flexible, narrower, goes into duodenum, commonly used for feeding but cannot be used for decompression because they collapse with suction)

Ideal placement of feeding tubes depends partly on the clinical situation. In general, a feeding tube placed in the stomach poses no greater aspiration risk than a feeding tube placed beyond the pylorus. For patients with high reflux risk, placement beyond the pylorus is often recommended, though supportive data is lacking. IV metoclopramide may aid in the passage of feeding tubes beyond the pylorus.

Xrays are often not necessary for NG tubes (e.g. Salem Sump) used for decompression. Instead, clinical confirmation can be obtained by visualizing return of gastric contents or warm water that is flushed in with a syringe.

Xrays are necessary to confirm placement of feeding tubes (enteral tubes). The unintentional placement of a feeding tube into the airway is a potentially life-threatening complication that is not always obvious.

Placement is sometimes difficult to determine with a portable radiograph of a poorly positioned patient.

Merely assuring that the tip of the feeding tube is over the gastric bubble is not adequate confirmation – one must follow the entire course of the tube to ensure that it does not follow the course of a bronchus. If there is any question, do not clear the feeding tube for use.

X-ray confirmation is required before using for medication, fluids or feedings

Placement must be confirmed by a radiologist.