Introduction

Chest radiography with the portable unit is the most commonly requested X-ray examination in the neonatal unit. Achieving high quality images can be depectively difficult. This page examines the issues and techniques peculiar to the neonatal unit.

Abbreviations and Terminology

UAC: Umbilical artery catheter
UVC: Umbilical vein catheter
ETT: Endotracheal tube
NGT: Nasogastric tube
TPT: Transpyloric tube
VP Shunt: Ventriculo-peritoneal shunt
CVC: Central Venous Catheter
VLBW: Very Low Birthweight
NEC: Necrotising Enterocolitis

Ground Rules

You learn quickly that radiography in the neonatal unit is different. The patients are very small, vulnerable and sometimes very ill. The following are some very simple dot point tips:

• wash your hands before entering the unit and on exiting. Also, wash your hands between babies (important)
• ensure that the baby's name matches the one on the request form (careful you don't get confused with twins)
  
• check the clinical information on the request form- this can influence what you include on the image
  
• don't run the mobile machine into the cot/incubator (surprisingly easy to do)
• ask the nurses for help- they know the babies, know their illnesses, and are used to handling them
• be careful to avoid patient rotation, particularly with chest radiography
• use a side marker (see Baker Cone)- left and right are not always clear from the anatomy, particularly in chest radiography
• check departmental protocol re removal of ECG leads
• think about radiation protection- horizontal ray technique considerations, gonad protection, long bone protection, the nurses fingers
  
• you are not the boss- if the nurse says the baby cant be moved..the baby cant be moved.
• use a cassette tray if there is one built into the cot/isolette
  

The Patients
The neonatal unit patients are small- this doesn't make the job easier...in many respects it makes the job harder. The multitude of attachments is also a challenge. The attachments seem to overwhelm the baby.



Radiation Protection

Operator Irradiation

The person holding the baby can receive an undesirable bonus image of their fingers. This is largely avoided by education, coning and diligence. The nurse holding the baby may not be as aware of the significance of her fingers in the LBD light as you are.

Side Markers

Side markers in the neonatal unit are important. The difficulty is that your side marker can appear to be almost as big as the baby's chest. There are two solutions that I am aware of Baker Cones Baker cones are pieces of lead rubber that have the side marker punched into them. Dedicated Neonatal Markers The marker on the left is simply to large for use in the Neonatal Unit. You don't want to cone out to include this relatively large marker. The marker on the left is the type used by the radiographers at the Adelaide Womens and Childrens Hospital. They also use these small markers with the operators initials. Importantly, the operators initials are engraved laterally on the marker- ie to the right on a right marker and to the left on a left marker. This ensures that if the marker is partly coned off, it is the operators initials that are coned off and not the "L" or "R".

Radiographic Technique

Cassette Name Window

If you are not using digital radiography technique, be aware of the patient name window on the cassette. Placing important anatomy over the name window of the cassette is very easy to do. Also, the umbilical vein catheter (UVC) tip apears to be in the right jugular vein. Check your department protocol regarding the amount of upper airway that you should include on the image. Some centres require all of the baby's upper airway to be included on a chest image

Exposure

This image is overexposed. This problem tends to be masked with CR and DR systems because of their greater exposure lattitude.

Skin Folds

This is a non-digital film-screen radiograph. There are a number of issues with this image the projection is apical. Note that the baby's clavicles are projected clear of the ribs. This can be avoided with caudal tube angle or angling the baby/cot head up. no side marker There are multiple skin folds (white arrows) Thses can be misinterpreted as a pneumothorax

Operator's Hands

This is a non-digital film-screen radiograph. There are a number of issues with this image The operator's hands are covering the upper half of the chest no side marker Pre-processing film scratches in lower half of image

Operator's Hands II

This image is circa 1966 with film/screen and manual processing. Note the manual processing characteristic radiused corners. There are several valid criticisms/observations that can be levelled at this radiograph there is only one cone mark visible the operator's fingers are in the image the top artifact (white arrow) is probably a perspex head box (for O2 therapy) there is a circular artifact that is produced by a hole in the perspex of the isolette.

Coning

This image is circa 1961. Once again it is taken using film/screen technology and manual processing. Note the following there are no cone marks (leaves you wondering how wide the cones were). I believe LBDs were around in 1969. The "R" at the end of the ID number should be on the patient's right side. Tension pneumperitoneum noted

Coning