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When you are summoned to the neonatal unit (commonly known as NNU, SBCU or NICU) for a 'check X-ray', it is often to establish the position of a tube, line or catheter. A knowledge of these lines is useful in producing an image that is appropriately positioned and coned.

Everything in the neonatal unit (NNU) can be abbreviated into a three letter acronym (TLA).

UAC: Umbilical artery catheter
UVC: Umbilical vein catheter
ETT: Endotracheal tube
NGT: Nasogastric tube
TPT: Transpyloric tube
VPS: Ventriculo-peritoneal shunt
CVC: Central Venous Catheter
TPN: Total parenteral nutrition

Umbilical Vein Catheter Insertion

• Identify and dilate the umbilical vein
• Place line into the lumen and advance to your premeasured goal
• Check to see if the line draws back and flushes
• If feeling resistance or “bouncing” – likely coiled in the liver

Umbilical Artery Catheter Insertion

• Dilate one of the arteries, go for the least tortuous, cut down stump if both are very tortuous
• Insert catheter to calculated length
• If resistance early, 1 to 3 cm, consider side approach or trying other artery
• If resistance further along or no blood return, likely in the leg, try to pull back and reposition or try the other artery
• May also try giving fentanyl for vasospasm

www.youthclinic.com/Pediatric%20lectures/Line%20Placement.ppt

This video demonstrates the insertion technique for a umbilical catheter in a mannequin	This is an instructional video on how to insert an umbilical catheter. The sound quality is awful and is not in English.

Source : NeoRay™ Bedside Radiography In the NICU Women’s Hospital, Newburgh, Indiana

The Case for Checking Lines with DR in NICU

Source: Unreferenced Powerpoint presentation from Deaconess Women’s Hospital, Newburgh, Indiana

I found a powerpoint presentation from the Deaconess Women’s Hospital, Newburgh, Indiana that argued the case for checking line in the Neonatal unit with mobile DR. This has intuitive appeal- a malpositioned line can do harm in a variety of different ways. Also, the mobile DR technique is efficient in that a malpositioned line can be quickly assessed, repositioned then reassessed.

The positioning of umbilical catheters in particular is easier to digest if you understand the foetal vascular anatomy

Source: Unknown

"Oxygenated blood from the placenta enters through the umbilical vein. Blood is shunted away from the liver and directly toward the inferior vena cava through the ductus venosus. Oxygenated blood in the ductus venosus mixes with deoxygenated blood in the inferior vena cava. Blood empties into the right atrium. Most of the blood is shunted to the left atrium via the foramen ovale. Blood flows into the left ventricle and out the aorta. A small amount of blood enters the right ventricle and pulmonary trunk, but much of this blood is shunted to the aorta through ductus arteriosus. Blood travels to the rest of the body, and the deoxygenated blood returns to the placenta through umbilical arteries. " quoted from Human Anatomy, First Edition McKinley & O'Loughlin

• Placed into the umbilical artery, through to the descending aorta
• Allows continuous blood pressure monitoring
• Allows for frequent blood gas, lab sampling
  www.youthclinic.com/Pediatric%20lectures/Line%20Placement.ppt
  

• The umbilical arteries are the direct continuation of the internal iliac arteries.
• A catheter passed into an umbilical artery will usually (but not always) enter the aorta via the internal iliac artery.
• Occasionally it will pass into the femoral artery via the external iliac artery or into the gluteal arteries.
• The femoral artery or gluteal artery are unsuitable sites for sampling, infusion, or blood pressure monitoring

	adapted from source: unknown
The umbilical artery catheter (UAC) characteristically deviates inferiorly before tracking up the aorta. See the lateral decubitus abdominal image below for further appreciation of the course of the umbilical artery.

Lateral

The UAC and UVC are seen in this supine decubitus abdominal image. UAC The umbilical artery catheter (UAC) can be seen to track inferiorly and posteriorly from the umbilicus before tracking up the aorta.

UAC in High Position	adapted from www.youthclinic.com/Pediatric%20lectures/Line%20Placement.ppt
UAC in Low Position	adapted from www.youthclinic.com/Pediatric%20lectures/Line%20Placement.ppt
There are two potential tip positions for the UAC. These are described as "high" or "low". The high position is at the level of thoracic vertebral bodies T6-T9. This position is above the coeliac axis (T12), the superior mesenteric artery (T12-L1), and the renal arteries (L1). This position is essentially "above the diaphragm". The low position is at the level of lumbar vertebral bodies L3-L4. This position is below the structures as above, and is above the aortic bifurcation (L4-L5). The inferior mesenteric artery arises from L3-L4. This position is essentially "above the aortic bifurcation". source

	http://www.adhb.govt.nz/newborn/TeachingResources/Radiology/Umbilical/LeftSubclavianUAC.jpg
This UAC appears to have taken a course along the right iliac artery or gluteal artery The UVC tip is in the pulmonary circulation	UAC in left subclavian artery

• Goal is to place the UVC above the diaphragm but below the heart

• UVC is directed into the umbilical vein, through the ductus venous, into the inferior vena cava
• Allows infusion of more hypertonic solutions
• Allows better nutrition through TPN
• Provides emergency access for fluids, resuscitation drugs and blood products

Original artwork by M.J.Fuller

This graphic is based on a venogram and is therefore a reasonable representation of actual anatomy. The UVC normally moves up the umbilical vein in a cranial direction where it meets the junction with the left and right portal vein within the liver. There is a direct communication between the umbilical vein and the ductus venosis. After travelling through the ductus venosis it encounters a second venous cross-roads at the level of the left and right hepatic vein. On travelling further in a cranial direction the UVC enters the inferior venacava. Note the positions of the vertebral bodies- these provide a guide as to where the UVC might have taken a wayward path.

adapted from source: unknown

The umbilical vein catheter (UVC) takes a characteristically different path to the Umbilical Artery Catheter (UAC). The umbilical vein is 2-3cm long and 4-5mm in diameter From the umbilicus, it passes cephalad and a little to the right It joins the left branch of the portal vein after giving off several large intrahepatic branches. The ductus venosus arises from the point where the UV joins the left portal vein See the lateral decubitus abdominal image below for further appreciation of the course of the umbilical vein.

UVC This lateral image gives an appreciation of the course of the umbilical vein and ductus venosis in relation to the liver

http://www.hawaii.edu/medicine/pediatrics/neoxray/neoxray.html

In this image the UAC is on the baby's right and the UVC is on the baby's left. This is the reverse of the usual configuration. Can you explain this anomaly? hint1: scroll up the page and look at the lines in the lateral supine decubitus abdominal image hint 2: look at the ribs and pelvis

	Original artwork by M.J.Fuller
The baby is rotated RPO. The UVC has deviated medially at the level of the left portal vein. It may also have looped in the capacious space at the junction of the umbilical vein and left portal vein.

	Original artwork by M.J.Fuller
Again, the UVC may have looped at the junction of the left portal vein and then travelled up the left portal vein

	Original artwork by M.J.Fuller
The UVC has deviated to the left at T8 which is the level of the left hepatic vein. The UVC tip is most likely to lie within the left hepatic vein

	Original artwork by M.J.Fuller
A similar appearance to the case above but at T11. This is the level of the left portal vein and most likely represents its tip position.

	Original artwork by M.J.Fuller
UVC takes a bend at T12/L1. The level and angle of the catheter suggests that it is in the portal vein with the tip possibly in the SMV bilateral pneumothoraces noted NGT folded in oesophagus ?folded

www.youthclinic.com/Pediatric%20lectures/Line%20Placement.ppt	adpated from Lakshmana Das Narla, MD Mark Horn, MD GaryK Lofland, MD Williarn B. Moskowitz, MD. Evaluation of Umbilical Catheter and Tube Placements in Premature Infants
UVC extends across foramen ovale into the left atrium then left ventricle	UVC extends across foramen ovale into the left atrium then left ventricle

	adpated from Lakshmana Das Narla, MD Mark Horn, MD GaryK Lofland, MD Williarn B. Moskowitz, MD. Evaluation of Umbilical Catheter and Tube Placements in Premature Infants
The UVC tip is in the pulmonary vein	UVC through foramen ovale into the left atrium and pulmonary vein. The Foramen Ovale is a hole between the right and left atria allowing blood to pass from the right side of the heart to the left without passing through the lungs.

	adapted from source: unknown
Same patient as above UVC repositioned- now in jugular vein

	adapted from source: unknown
UVC well into jugular vein ? UVC in UA (double lumen catheter)and UAC in UV (single lumen catheter

	adapted from source: unknown
UVC tip in right atrium	UVC tip in right atrium

	Original artwork by M.J.Fuller
The UVC deviates to the right at the level of the right portal vein. ? Air in portal venous branches associated with umbilical venous catheter insertion

Transient Portalvenous air

The UVC tip has tracked into the liver and there appears to be portal venous gas. Air in portal venous branches can be associated with umbilical venous catheter insertion. Inconsequential transient portal venous air can be seen immediately after umbilical venous catheter insertion and should not necessarily be attributed to necrotizing enterocolitis. Alan E. Schlesinger1, Richard M. Braverman1 and Michael A. DiPietro2 AJR 2003; 180:1147-1153

Double Catheter Technique

Source: Mandel: J Pediatr, Volume 139(4).October 2001.591-592

The double catheter technique is based on the premise that once the first attempt catheter has occupied the wrong vessel, the second attempt catheter will be more likely to enter the correct vessel (the incorrect vessel is blocked by the catheter from the first attempt). Mandel, Dror MD; Mimouni, Francis B. MD; Littner, Yoav MD; Dollberg, Shaul MD The Journal of Pediatrics, Double catheter technique for misdirected umbilical vein catheter. Volume 139(4),October 2001,pp 591-592

The first catheter (UVC1) deviates to the left to enter (most likely) the splenic vein. The second catheter (UVC2) ascends vertically to enter the IVC and the right atrium. UAC indicates the umbilical artery catheter with the tip located at T6.

This Nasogastric tube (NGT) is in an acceptable position in the stomach.	This nasogastric tube (NGT) has become caught at the tip mid-oesophagus. As it has continued to be advanced it has caused a bend in the tube.

The transpyloric tube (TPT) is similar to a nasogastric tube (NGT) except that it is longer and intended to have its tip sited distal to the pylorus. The ventriculo-peritoneal shunt provides a drainage path from the ventricles of the brain to the peritoneal cavity

Starting at the top: endotracheal tube (black outline arrow) peripherally inserted venous line (white outline arrow) Nasogastric tube (solid white arrow) Transpyloric tube (solid black wrrow)

Peripheral Venous Catheter Insertion Sites

"1.Hand

Dorsal arch veins

Are best seen on the back of the hand but are usually larger and easier to enter just over the back of the wrist. Skin entry should be more distally. These veins can often be palpated in a larger infant rather better than they can be seen. IV's inserted here are easily splinted and any infiltration easily spotted, so are the preferred site.

Cephalic Vein, in anatomical snuffbox

This is often quite large, especially if the dorsal arch is well used. This vein can often be felt rather better than it can be seen and is one of the veins to try if one must do it "blind" in a large baby. The feeder veins over the dorsum of the hand in the first interspace need to be treated with respect, as it is possible to cannulate an artery here, risking loss of a thumb, or part thereof. (princeps pollicis artery). This is present in about 10% of infants. If present is usually the sole supply to thumb.
The cephalic vein is large and tends to last quite well. It is a good secondary site. It can also be used for insertion of percutaneous central venous catheters.

2.Wrist

Volar aspect

Veins are easily seen on the volar side of the wrist. They are usually quite small and fragile and, while easily cannulated, do not last well.
They are useful secondary sites, but must be carefully watched when noxious substances (eg Dopamine, Vancomycin) are infused, as they are prone to "burn".

3.Cubital Fossa

Median antecubital, Cephalic and Basilic veins

Are easy to hit and tend to last quite well if splinted properly. Median nerve and brachial artery are both vulnerable. These veins are the preferred sites for insertion of percutaneous central venous catheters. These should be avoided unless absolutely necessary in any infant likely to need long term IV therapy.

4.Foot

Dorsal arch

Are small, but easily cannulated and last surprisingly well. Vein on lateral aspect, running below malleolus, is easy of access but must be splinted carefully and watched for infiltration.
Veins leading up to short saphenous are often good value.

Saphenous vein, ankle

Runs reliably just anterior to medical malleolus and is large and straight. Easy to access and lasts well although not always readily visualised.

5.Leg

Saphenous vein. Knee

Runs just behind medial aspect of knee. Often visible both behind knee and as it curves around top of tibia. Access is easy and lasts well if properly splinted. However, this vein is a good site for the insertion of percutaneous central venous catheters and should be avoided if possible in any infant likely to need long term IV therapy.

6.Scalp

Superficial temporal

Runs anterior to ear and is accessible over a distance of 5-8 cm. in most babies. Is accessible and lasts well. However, this vein is a good site for the insertion of percutaneous central venous catheters and should be avoided if possible in any infant likely to need long term IV therapy.
One hazard is the proximity of the temporal artery, which runs beside it. In small infants it can be almost impossible to tell the difference, even when the catheter has been inserted. It is important to try to identify the vessels separately, by careful palpation and by observation in a good light (in the smaller infants one can see the artery pulsate). If the catheter is in an artery, it must be removed.

Posterior auricular

A moderate sized vein runs behind the ear and over the temporal bone. This vein and its branches are accessible and last quite well. There is a moderate risk of cannulating an artery in this area as well, so care must be taken.

Supratrochlear vein

This vein runs down from scalp over forehead and bridge of nose. It usually needs a shave of the hair to be accessible. Is quite easy to access and easily secured and lasts well.
The major drawback is that that the vein has anastomoses via the orbital plexus with the cavernous sinus. Thrombophlebitis of the vein has therefore a direct communication intracranially.
A further disadvantage is that any 'burn' caused by infiltration will be in the middle of the forehead. Because of these factors, it should only be used as a vein of last resort.
Scalp veins should only be used once other alternatives are exhausted. Most involve at least partial shaving of the head. Infants will take 6-12 months to grow hair back properly. This distresses parents and makes the baby look 'funny' for the first year or so."

Source Neonatal Handbook, Royal Childrens Hospital, Melbourne

Radiography Technique

Upper Limb

Check your departmental policy regarding the arm position for venous catheters. The Southern West Midlands Newborn Network recommend the following "If the cephalic vein has been cannulated the x-ray should be taken with the arm adducted. If the basilic vein has been cannulated the x-ray should be taken with the arm abducted. Contrast medium may be used to aid visualisation of the line. Although not reported in neonates, there is a theoretical risk of reaction to the contrast medium. The tip of the PICC should lie outside the heart, ideally by 1cm in a baby <1250g and by 2cm in a baby >1250g." (Southern West MIidlands Newborn Network) It is important to note that the catheter tip position will change with the baby's arm movements. The following research finding are noteworthy "Arm movements were associated with significant displacement of catheters. Catheters that were placed via the basilic or axillary vein migrated toward the heart with adduction of the arm, whereas those that were placed via the cephalic vein moved away from the heart with adduction. Flexion of the elbow displaced catheters that were placed in the basilic or cephalic vein below the elbow toward the heart but did not have any effect on catheters that were placed via the axillary vein. For catheters that were placed in the basilic vein, simultaneous shoulder adduction and elbow flexion caused the greatest movement toward the heart (15.11 + or - 1.22 mm). We were able to reposition correctly inappropriately placed catheters in 9 of 10 patients by using arm movements." Ali M. Nadroo, Ronald B. Glass, Jing Lin, Robert S. Green and Ian R. Holzman Central Catheters in Neonates, Pediatrics 2002;110;131-136 The person who has inserted the catheter may not appreciate it being repositioned by the radiographer!

source: unknown

	This longline was suspected to be in artery rather than vein. An ultrasound was requested to confirm the position.
	Original artwork by M.J.Fuller
This is an ultrasound image of the baby's left axillary vessels. It was clear on the live ultrasound image that the longline was within the axillary artery rather than vein. The ultrasound probe was positioned in the baby's axilla.	Note that the artery tends to keep a more uniform round shape. The vein is more likely to appear flattened and will change shape when compressed with the ultrasound probe. The doppler flow characteristics also clearly distinguished artery from vein

Source Ali M. Nadroo, Ronald B. Glass, Jing Lin, Robert S. Green and Ian R. Holzman Central Catheters in Neonates, Pediatrics 2002;110;131-136	Source Ali M. Nadroo, Ronald B. Glass, Jing Lin, Robert S. Green and Ian R. Holzman Central Catheters in Neonates, Pediatrics 2002;110;131-136
Note the position of this CVC in a baby with arm abducted and elbow extended	Same baby with same CVC line with arm adducted and elbow flexed.

Central Venous Catheter (CVC) Longline- leg

The central venous catheter has been inserted in the right leg and its tip is difficult to localise precisely. This is a common problem with CVC lines and emphasises the need for good quality images when checking CVC lines. A study of printed CR images vs soft copy CR images reported a long line detection rate of 66.7% vs 95.6% respectively. (A Evans, J Natarajan, C J Davies, 2004). Other suggestions include "The authors emphasise the importance of verifying neonatal long line position using contrast, as the exact localisation of the catheter tip can be difficult on plain radiographs. As an alternative, Groves et al4 have described the use of colour Doppler to aid ultrasonographic line tip visualisation." T M Berger, M Stocker, J Caduff Gonad protection could have been used to good effect

A magnified view demonstrates the CVC tip to be at the level of the first sacral vertebra

	This abdominal X-ray examination was requested after a difficult long line insertion into the left saphenous vein. Further clarification of the tip position was undertaken using ultrasound imaging. The longline tip position was established to be in the arterial circulation.

Central Venous Catheter (PICC) - arm

source: unknown

	adapted from source: unknown
The tip of the longline is in the proximal brachiocephalic vein. (lower white arrow) The top white arrow identifies the endotracheal tube (ETT) The black arrow identifies the nasogastric tube (NGT)

	adapted from source: unknown
Contrast injected through a subclavian line. ? tip in jugular vein

Injection of contrast into jugular CV line demonstrates filling of the vascular plexus in the right shoulder as well as filling of the subclavian vein and the axillary vein

	adapted from source: unknown
Central line in Right Ventricle (arrow)

	adapted from source: unknown
Long left central line in right heart then subclavian vein

	adapted from Ali M. Nadroo, Ronald B. Glass, Jing Lin, Robert S. Green and Ian R. Holzman Central Catheters in Neonates, Pediatrics 2002;110;131-136
Central line inserted in cephalic vein with tip in right axillary vein (tip arrowed)	Central line in right axillary vein graphic

This baby has a right sided pneumothorax. The top white arrow identifies the lung edge An intercostal drain is malpositioned in the soft tissues of the chest wall.

This baby has extensive subcutaneous emphysema. Both intercostal drains are malpositioned with their sideholes possibly in the chest wall soft tissues

This baby has a right sided pneumothorax. Also note LPO position intercostal tube malposition mediastinal shift deep suclus sign (white arrow) silhouette sign right hemidiaphragm NGT

ET tube placement, should be halfway between the thoracic inlet and the carina

The endotracheal tube tip is in the right main bronchus. A hint of opacity in the RUL suggests that it may be partly within the bronchus intermedius. There is atelectasis of the left lung. There are several skin folds over the left lung About 10% of ETT are initially placed in the right main stem bronchus With time, the left lung becomes atelectatic If on ventilator, the right lung may be hyperinflated May lead to pneumothorax or tension pneumothorax http://www.learningradiology.com/archives04/COW%20129-Atelectasis-ETT/atelectasiscorrect.htm

These two images on the same baby are taken 15 minutes apart. This image shows the tip of the ETT favouring the RMB to the detriment of the left lung.	With the ETT tube withdrawn a CXR 15 minutes later shows considerable improvement of the aeration of the left lung.

Point of Interest

	By Fred W. Wright Radiology of the Chest and Related Conditions: Together with an Extensive Illustrative Collection of Radiographs CRC Press, 2002

The endotracheal tube (ETT) tip is in the bronchus intermedius. When the tip is in the bronchus intermedius, RUL will also become atelectatic along with all of left lung

This baby has an ET tube malpositioned in the oesophagus. Note the baby's trachea has deviated to the right and is positioned alongside the ET tube