Pathology - Chest/Abdomen (Unit 1-2)

CXRs are used to verify the proper placement of what internal devices?

• Endotracheal tube

• Central venous catheter

• Swan-Ganz catheter

• Transvenous cardiac pacemaker

Placement and purpose of the Endotracheal Tube (ET):

• Keeps airway open if obstruction or respiratory failure.

• End of tube 5-7 cm above carina

Placement and purpose for Central Venous Catheter:

• Rapid infusion of fluids, nutrition, drugs, dialysis over a long period of time.

• Measures central venous pressure (CVP)

• Placement in internal jugular vein, subclavian vein, and common femoral vein.

Placement and purpose for Swan-Ganz Catheter:

• Monitors heart function and blood flow. Cardiac output and CVP

• Positioned in R or L main pulmonary artery, with the tip not extending beyond the medial lung field

Placement and purpose for Transvenous Cardiac Pacemaker:

• Maintain cardiac rhythm

• Tip of pacemaker electrode should be positioned at the apex of right ventricle

Cystic Fibrosis

Secretion of excessively viscous (thick) mucus causing severe damage to the lungs, digestive system, and other organs.

What is the typical life expectancy for individuals with cystic fibrosis?

30-40 years

Cystic Fibrosis: Additive or Destructive?

Additive condition - increase kVp

Hyaline Membrane Disease

Idiopathic respiratory distress syndrome is caused by lack of surfactant (lubricant) in immature lungs. In premature newborns.

Hyaline Membrane Disease: Additive or Destructive?

No exposure factor change necessary

Hyaline Membrane Disease looks like on XR

Air bronchogram (spiderweb air pocket)

COPD (Chronic Obstructive Pulmonary Disease)

Chronic obstruction of the airways leads to an ineffective exchange of respiratory gases and makes breathing difficult.

What are the two most common types of COPD?

• Chronic bronchitis

• Emphysema

Emphysema

Distension of the distal air spaces as a result of the destruction of alveolar walls and obstruction of small airways.

Emphysema: Additive or Destructive?

Destructive - decrease mAs

Emphysema looks like on XR

Severe overinflation of lungs along with flattening and even a superiorly concave configuration of the hemidiaphragms.

Chronic Bronchitis

Excessive tracheobronchial mucus production leading to the obstruction of small airways.

Tuberculosis (TB)

Lung disease caused by bacteria and spreads via droplets in the air; no longer prevalent in the US

• Latent and Active

Active TB

Infectious; chest pain, SOB, coughing. Curable

Latent TB

No symptoms, not infectious, ticking time bomb

Active TB: Additive or Destructive?

Additive - increase kVp

Pneumoconiosis

Inhaled irritants retained permanently in the alveolar sacs causing irreversible damage.

• Silicosis

• Asbestosis

• Anthracosis

Silicosis

Most common form of pneumoconiosis, caused by silica quartz dust in mining/sandblasting

Asbestosis

Pneumonconiosis caused by inhlation of asbestos in manufacturing.

Anthracosis

Pneumoconiosis caused by inhalation of anthracite (coal) dust.

Pneumoconiosis: Additive or Destructive?

No exposure factor change necessary

Pneumonia

Inflammation of the lung caused by bacteria and viruses

• Viral - both sides of lungs

• Bacterial - one side of lungs

What are the three types of pneumonia radiographic patterns?

• Alveolar, or air-space, pneumonia

• Bronchopneumonia

• Interstitial pneumonia

Alveolar Pneumonia

Homogenous consolidation of right lung with associated bronchograms. Bacterial. Inflammatory condition

Bronchopneumonia

Ill-defined consolidation at right base. Bacterial

Interstitial Pneumonia

Diffuse infiltrate; air space consolidation obscures heart border. Viral

Atelectasis

Complete or partial collapse of the entire lung caused by bronchial obstruction.

Atelectasis: Additive or Destructive?

Additive

Pneumothorax

Air in the pleural cavity resulting in partial or complete collapse of the lungs.

What are the causes of a Pneumothorax?

• Rupture of a subpleural bulla (air pockets)

• Spontaneous event

• Trauma

• Iatrogenic causes

Pneumothorax: Additive or Destructive?

Destructive

PA Chest: Image Criteria

• Manubrium superimposed by T4

• 1” of apices above clavicles

PA Chest Tilted Forward/Anteriorly

• Lungs and heart are foreshortened

• Vertical clavicles

• Manubrium at T5 or lower

• More than 1” of apices

• Ribs are more curved

• Upper MCP was tilted toward IR

PA Chest Tilted Backwards/Posteriorly

• Lungs and heart are foreshortened

• Horizontal clavicles

• Manubrium at T1-3

• Less than 1” of the apices

• Ribs are more horizontal

• MCP titled away from IR

PA Chest: Is this Image Good?

• Manubrium is at T1

  • Patient was tilted backwards. Bring pt towards IR.

• Did not get all 10 ribs

  • Have patient do a deeper inspiration

Distinguishing R and L lungs on Lateral Chest

1. Gastric bubble

2. Lung tissue

3. Heart Shadow

What position shifts the heart to superimpose the sternum anteriorly?

LPO

What position shifts the left lung toward the anterior direction?

LPO

What position demonstrates the left lung more anterior to sternum on image?

Describes an LPO position, but the left lung does not get demonstrated due to OID

What position shifts the heart posterior to the sternum?

LAO

What position demonstrates the right lung more anterior to sternum on image?

LAO

What position shifts the right lung more toward the anterior direction?

LAO

How much do ribs need to be separated on a lateral CXR for a correction to be necessary?

Greater than 0.5”

A left lateral chest xray demonstrates the right and left ribs separated about 0.25". what caused this and how should it be fixed?

Caused by rotation; however, no fix necessary because it is less than 0.5”.

Lateral Chest: Is this Image Good?

• R and L ribs are separated >0.5” (span of finger)

• Humeral soft tissue obscures anterior lung apices

  • Raise arms until humeri are vertical

• Do not see any anterior lungs which means patient is in an LPO

  • Rotate patient’s right thorax anteriorly

Lateral Chest: Is this Image Good?

• Need 10 ribs for good inspiration

  • Make the patient take a deeper inspiration and make sure to expose on second inspiration.

An AP CXR requires ______ angle to prevent clavicles from obscuring the apices.

± 5 degree caudad

• CR perp. to sternum

AP Chest: Is this Image Good?

• Poor inspiration

  • Patient needs to do a deeper inspiration

• Clavicles are too vertical

  • Depress the shoulders

AP Chest: Is this Image Good?

• <1” of apices

• Posterior ribs are horizontal

• CR was angled cephalically

  • Adjust so the angle is caudad

AP Chest: Is this Image Good?

• Left clavicle is foreshortened

• Left SC joint is farther from vertical column

• Left side posterior ribs are longer than the right

• Head and body are rotated to the left

  • Rotate left side away from the IR

Describe how the position of the SC joints can indicate the direction of rotation in a poorly positioned AP CXR

LPO - Left SC joint is farther from vertebral column. Right SC superimposed

RPO - Right SC joint is farther from vertebral column. Left SC superimposed

PA CXR SC Joints

RAO - Right SC joint is closer to midline than left

LAO - Left SC joint is closer to midline

If the left SC joint is demonstrated farther from the vertebral column than the right joint, the pt is rotated ____?

LPO/LAO

If the right SC joint is demonstrated farther from the vertebral column than the left joint, the pt is rotated ____?

RPO/RAO

Peritoneum

Double-walled sac that lines the abdominal cavity and covers organs (parietal and visceral).

Parietal Peritoneum

Along the abdominal wall

Visceral Peritoneum

Covers the organs

Peritoneal Cavity

Cavity contains serous fluid

Ascites

Abnormal accumulation of fluid in the peritoneal cavity of the abdomen

• Displaces the bowel centrally

Ascites: Additive or Descructive?

Additive - increase kVp

Causes of ascites

• Cirrhosis of the liver

• Metastatic disease to the peritoneal cavity

• May be treated with diuretics, drainage

Pneumoperitoneum

Free air in the peritoneal cavity

Causes of pneumoperitoneum

Perforation of a gas-containing viscus (intestine)

Pneumoperitoneum: Additive or destructive?

Destructive

What should you do if the patient cannot stand for the abdominal XR and you need to see air-fluid levels?

Do a Left Lateral Decub

Peritonitis

Redness and swelling (inflammation) of the lining of the peritoneum.

What can typically cause Peritonitis?

An infection from a hole in the bowel or a burst appendix.

Dynamic or Mechanical Bowel Obstruction

Partial or complete blockage in the intestine due to adhesions or foreign body

• Can happen anywhere in the intestinal tract, but common in small bowel

Fibrous adhesions

Fibrous band of tissue interrelates with the intestine, creating a blockage

• Most common cause of mechanically based obstruction

• Distended loops of air-filled small intestine

Fibrous Adhesions: Additive or Destructive?

Destructive

Ileus (Non-mechanical obstruction): Additive or Destructive?

Destructive

Ileus

Non-mechanical obstruction involving large amounts of air, often resolves within 1-3 days. Common for post-op patients.

Adynamic ileus

• Occurs more often than mechanical bowel obstruction

• Common disorder of intestinal motor activity

• Fluid and gas do not progress normally

Factors that impede intestinal motility:

• Neural

• Hormonal

• Metabolic

Causes of Adynamic ileus:

• Peritonitis

• Medications that decrease intestinal peristalsis

• Electrolyte and metabolic disorders

• Trauma

Intussusception

Telescoping of one part of the intestinal tract into another because of peristalsis

• Common in children

• Air-filled “coiled spring” appearance

Intussusception: Additive or Destructive?

Destructive

Volvulus

Twisting of a loop of intestine, which creates and obstruction

• Bird’s beak appearance

• Common sites: Cecum and Sigmoid

• Ischemia and necrosis is a concern

AP Abdomen: Image Criteria

• T12 to pubic symphysis

• L4 at center (iliac crest)

• Psoas muscles

Where should a Nasogastric Tube end?

Tip should be visible at least 10 cm (4”) beyond the gastroesophageal junction. In LUQ.

What is the purpose of NG tubes?

Used for feeding or removal of gas/secretions by suction (decompression).

Patient should be upright for to ______ minutes before taking images to allow ______ to move away from the abdominal structures and rise to levels of diaphragms.

• 5-20 minutes

• Air

Abdominal Breathing Instructions

First expiration

• Full expiration: T8-9

• Full inspiration: T12

The diaphragm can move as much as ___ inches from full inspiration to expiration.

4

KUB: Is this Image Good?

• Not centered to iliac crests; missing pubic symphysis.

  • Do a bladder shot or center CR 1 inch lower

Upright Abdomen: Is this Image Good?

• Domes of diaphragm not included

• CR centered too low

  • Bring the CR higher - 2” above crests

Upright Abdomen: Is this Image Good?

• Diaphragm is at T11; full inspiration

  • Diaphragm should be at T9; full expiration

• CR is good

Left Lateral Decub: Is this Image Good?

• Left ribs are elongated indicating LPO position

  • Rotate right side back toward IR

• CR is too high

  • Center CR 2” above crests

On abdomen XRs what does it look like when patient is improperly obliqued?

LPO - Left ribs elongated, left iliac wing is wider

• Rotate right side back to IR

RPO - Right ribs elongated, right iliac wing is wider

• Rotate left side back to IR