Mariam M. Said

Khodayar Rais-Bahrami

30 Umbilical Vein Catheterization

A. Indications

1. Primary

a. Emergency vascular access for fluid and medication

infusion and for blood drawing

b. Long-term central venous access in low-birthweight

infants. If the line is to be used long-term, particularly if parenteral nutrition is to be infused by this

route, the same aseptic techniques must be used to

prevent line-related sepsis as are used for any central

venous line (see Chapter 32).

c. Exchange transfusion

2. Secondary

a. Central venous pressure monitoring (if catheter

across ductus venosus)

b. Diagnosis of total anomalous pulmonary venous

drainage below the diaphragm (1)

B. Contraindications

1. Omphalitis

2. Omphalocele

3. Necrotizing enterocolitis

4. Peritonitis

C. Equipment

1. Catheter—same as for umbilical artery catheterization,

except:

a. 3.5-French (Fr) catheter for infants weighing <3.5 kg

b. 5-Fr catheter for infants weighing >3.5 kg

c. Double lumen umbilical venous catheters may be

used in critically ill neonates to allow administration

of inotropes or medications.

d. Catheters used for exchange transfusion (removed

after procedure) should have side holes. This

reduces risk of sucking thin wall of inferior vena

cava against catheter tip, with possible vascular perforation (2). Avoid double lumen catheters for

exchange transfusions.

2. Other equipment as for umbilical artery catheter, but

omit 2% lidocaine (see Chapter 29, C)

D. Precautions

1. Keep catheter tip away from origin of hepatic vessels,

portal vein, and foramen ovale. Catheter tip should

lie ideally at the junction of the inferior vena cava and

the right atrium. The tip should at least be well into the

ductus venosus to protect the liver from receiving inappropriate infusions (3). Sometimes it will not be possible to advance the catheter through the ductus venosus.

Vigorous attempts to advance are to be avoided. In an

emergency, vital infusions (avoid very hypertonic solutions) may be given slowly after pulling catheter back

into umbilical vein (approximately 2 cm) and checking

blood return.

2. Check catheter position prior to exchange transfusion.

Avoid performing exchange transfusion with catheter

tip in portal system or intrahepatic venous branch (see

Fig. 30.1)

3. Once secured, do not advance catheter into vein.

4. Avoid infusion of hypertonic solutions when catheter

tip is not in inferior vena cava.

5. Do not leave catheter open to atmosphere (danger of

air embolus).

6. Avoid using a central venous pressure monitoring catheter for concomitant infusion of parenteral nutrition

(risk of sepsis).

7. Be aware of potential inaccuracies of venous pressure

measurements in inferior vena cava (see Chapter 32).

E. Technique (See Procedures Website

for Video)

Anatomic note: In the full-term infant, the umbilical vein is

2 to 3 cm in length and 4 to 5 mm in diameter. From the

umbilicus, it passes cephalad and slightly to the right, where

it joins the portal sinus, a confluence of the umbilical vein

with the right and left intrahepatic portal veins. The portal

veins have intrahepatic branches that are distributed directly

to the liver tissue. The ductus venosus becomes a continuation of the umbilical vein by arising from the left branch of

the portal vein, directly opposite where the umbilical vein

joins it. The ductus is located in a groove between the right

 

63. Moncino MD, Kurtzberg J. Accidental heparinization in the newborn: a case report and brief review of the literature. J Perinatol.

1990;10:399.

64. Landers S, Moise AA, Fraley JK, et al. Factors associated with

umbilical catheter related sepsis in neonates. Am J Dis Child.

1991;145:675.

65. Narendran V, Gupta G, Todd DA, et al. Bacterial colonization of

indwelling vascular catheters in newborn infants. J Paediatr Child

Health. 1996;32:391.

66. Hwang H, Murphy JJ, Gow KW, et al. Are localized intestinal

perforations distinct from necrotizing enterocolitis? J Pediatr Surg.

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67. Book LS, Herbst JJ. Intraarterial infusions and intestinal necrosis

in the rabbit: potential hazards of umbilical artery injections of

ampicillin, glucose, and sodium bicarbonate. Pediatrics. 1980;

65:114.

68. Simpson JS. Misdiagnosis complicating umbilical vessel catheterization. Clin Pediatr. 1977;16:569.

69. Biagtan J, Rosenfeld W, Salazard D, et al. Herniation of the

appendix through the umbilical ring following umbilical artery

catheterization. J Pediatr Surg. 1980;15:672.

70. Bavikatte K, Hillard J, Schreiner RL, et al. Systemic vascular cotton fiber emboli in the neonate. J Pediatr. 1979;95:61.

71. Abramowsky CR, Chrenka B, Fanaroff A. Wharton jelly embolism: an unusual complication of umbilical catheterization.

J Pediatr. 1980;96:739.

72. McGravey VJ, Dabiri C, Bean MS. An unusual twist to umbilical

artery catheterization. Clin Pediatr. 1983;22:587.

73. Crie JS, Hajar R, Folger G. Umbilical catheter masquerading at

echocardiography as a left atrial mass. Clin Cardiol. 1989;12:728.

74. Sakurai M, Donnelly LF, Klosterman LA, et al. Congenital diaphragmatic hernia in neonates: variations in umbilical catheter

and enteri`c tube position. Radiology. 2000;216:112.

173

 

172 Section V ■ Vascular Access

52. Francis JV, Monagle P, Hope S, et al. Occlusive aortic arch

thrombusina pretermneonate.Pediatr Crit Care Med.2010;11:e13.

53. Gupta JM, Roberton NRC, Wigglesworth JS. Umbilical artery

catheterization in the newborn. Arch Dis Child. 1968;43:382.

54. Lividatis A, Wallgren G, Faxelius G. Necrotizing enterocolitis

after catheterization of the umbilical vessels. Acta Paediatr Scand.

1970;63:277.

55. Bauer SB, Feldman SM, Gellis SS, et al. Neonatal hypertension:

a complication of umbilical artery catheterization. N Engl J Med.

1975;293:1032.

56. Muñoz ME, Roche C, Escribá R, et al. Flaccid paraplegia as

complication of umbilical artery catheterization. Pediatr Neurol.

1993;9:401.

57. Henry CG, Gutierrez F, Joseph I, et al. Aortic thrombosis presenting as congestive heart failure: an umbilical artery catheter complication. J Pediatr. 1981;98:820.

58. Murphy KD, Le VA, Encarnacion CE, et al. Transumbilical intravascular retrieval of an umbilical artery catheter. Pediatr Radiol.

1995;25:S178.

59. Hillman LS, Goodwin SL, Sherman WR. Identification of plasticizer in neonatal tissues after umbilical catheters and blood products. N Engl J Med. 1975;292:381.

60. Gaylord MS, Pittman PA, Bartness J, et al. Release of benzalkonium chloride from a heparin-bonded umbilical catheter with

resultant factitious hypernatremia and hyperkalemia. Pediatrics.

1991;87:631.

61. Cochrane WD. Umbilical artery catheterization. In: Iatrogenic

Problems in Neonatal Intensive Care. Report of the 69th Ross

Conference of Pediatric Research. Columbus, OH: Ross

Laboratories; 1976:28.

62. Johnson JF, Basilio FS, Pettett PG, et al. Hemoperitoneum secondary to umbilical artery catheterization in the newborn.

Radiology. 1980;134:60.

 

38. Hermansen MC, Hermansen MG. Intravascular catheter complications in the neonatal intensive care unit. Clin Perinatol.

2005;32:141.

39. Miller D, Kirkpatrick BV, Kodroff M, et al. Pelvic exsanguination

following umbilical artery catheterization in neonates. J Pediatr

Surg. 1979;14:264.

40. Ramasethu J. Complications of Vascular Catheters in the

Neonatal Intensive Care Unit. Clin Perinatol. 2008;35:199.

41. MacDonald MG, Chou MM. Preventing complications from

lines and tubes. Semin Perinatol. 1986;10:224.

42. Schreiber MD, Perez CA, Kitterman JA. A double-catheter technique for caudally misdirected umbilical arterial catheters.

J Pediatr. 1984;104:768.

43. Chidi CC, King DR, Bates E. An ultrastructural study of intimal

injury induced by an indwelling umbilical artery catheter.

J Pediatr Surg. 1983;18:109.

44. Clark JM, Jung AL. Umbilical artery catheterization by a cut

down procedure. Pediatrics (Neonatol Suppl). 1977;59:1036.

45. Carey BE, Zeilinger TC. Hypoglycemia due to high positioning

of umbilical artery catheters. J Perinatol. 1989;9:407.

46. Van Leeuwen G, Patney M. Complications of umbilical artery

catheterization: peritoneal perforation. Pediatrics. 1969;44:1028.

47. Wyers MR, McAlister WH. Umbilical artery catheter use complicated by pseudoaneurysm of the aorta. Pediatr Radiol. 2002;32:199.

48. Giannakopoulou C, Korakaki E, Hatzidaki E, et al. Peroneal

nerve palsy: a complication of umbilical artery catheterization in

the full-term newborn of a mother with diabetes. Pediatrics.

2002;109:e66.

49. Seibert JJ, Northington FJ, Miers JF, et al. Aortic thrombosis after

umbilical artery catheterization in neonates: prevalence of complications on long-term follow-up. AJR. 1991;156:567.

50. Martin JE, Moran JF, Cook LS, et al. Neonatal aortic thrombosis

complicating umbilical artery catheterization: successful treatment with retroperitoneal aortic thrombectomy. Surgery. 1989;

105:793.

51. Greenberg R, Waldman D, Brooks C, et al. Endovascular treatment of renal artery thrombosis caused by umbilical artery catheterization. J Vasc Surg. 1998;28:949.

 

20. Dunn P. Localization of the umbilical catheter by post-mortem

measurement. Arch Dis Child. 1966;41:69.

21. Rosenfeld W, Biagtan J, Schaeffer H, et al. A new graph for insertion of umbilical artery catheters. J Pediatr. 1980;96:735.

22. Rosenfeld W, Estrada R, Jhaveri R, et al. Evaluation of graphs for

insertion of umbilical artery catheters below the diaphragm.

J Pediatr. 1981;98:627.

23. Shukla H, Ferrara A. Rapid estimation of insertional length

of umbilical catheters in newborns. Am J Dis Child. 1986;140:

786.

24. Latini G. Potential hazards of exposure to di-(2-ethylhexyl)-

phthalate in babies. Bio Neonate. 2000;78:269.

25. Bloom BT, Nelson RA, Dirksen HC. A new technique: umbilical

arterial catheter placement. J Perinatol. 1986;6:174.

26. Squire SJ, Hornung TL, Kirchhoff KT. Comparing two methods

of umbilical artery catheter placement. Am J Perinatol. 1990;7:8.

27. Stewart DL, Wilkerson S, Fortunate SJ. New technique for stabilizing umbilical artery catheters in very low birth weight infants.

J Perinatol. 1989;9:458.

28. Sherman NJ. Umbilical artery cutdown. J Pediatr Surg. 1977;

12:723.

29. Hashimoto T, Togari H, Yura J. Umbilical artery cutdown: an

improved procedure for reinsertion. Br J Surg. 1985;72:194.

30. Waffarn F, Devaskar UP, Hodgman JE. Vesico-umbilical fistula: a

complication of umbilical artery cutdown. J Pediatr Surg. 1980;

15:211.

31. Mata JA, Livne PM, Gibbons MD. Urinary ascites: complication

of umbilical artery catheterization. Urology. 1987;30:375.

32. Diamond DA, Ford C. Neonatal bladder rupture: a complication

of umbilical artery catheterization. J Urol. 1989;142:1543.

33. Nagarajan VP. Neonatal bladder injury after umbilical artery

catheterization by cutdown. JAMA. 1984;252:765.

34. Lehmiller DJ, Kanto WP Jr. Relationships of mesenteric thromboembolism, oral feeding and necrotizing enterocolitis. J Pediatr.

1978;92:96.

35. Davey AM, Wagner CL, Cox C, et al. Feeding premature infants

while low umbilical artery catheters are in place: a prospective,

randomized trial. J Pediatr. 1994;124:795.

36. Davies MW, Mehr S, Morley CJ. The effect of draw-up volume

on the accuracy of electrolyte measurements from neonatal arterial lines. J Pediatr Child Health. 2000;36:122.

37. Schulz G, Keller E, Haensse D, et al. Slow blood sampling from

an umbilical artery catheter prevents a decrease in cerebral oxygenation in the preterm newborn. Pediatrics. 2003;111:e73.

 

adding heparin in very low concentration to the infusate to prolong the patency of umbilical

artery catheters. Am J Perinatol. 1993;10:229.

9. Horgan MJ, Bartoletti A, Polansky S, et al. Effect of heparin

infusates in umbilical arterial catheters on frequency of thrombotic complications. J Pediatr. 1987;111:774.

10. Butt W, Shann F, McDonnell G, et al. Effect of heparin concentration and infusion rate on the patency of arterial catheters. Crit

Care Med. 1987;15:230.

11. Bosque E, Weaver L. Continuous versus intermittent heparin

infusion of umbilical artery catheters in the newborn infant.

J Pediatr. 1986;108:141.

12. Hentschel R, Weislock U, Von Lengerk C, et al. Coagulationassociated complications of indwelling arterial and central venous

catheters during heparin prophylaxis: a prospective study. Eur

J Pediatr. 1999;158:S126.

13. Barrington KJ, Umbilical artery catheters in the newborn: effects

of heparin. Cochrane Database Syst Rev. 2000;CD000507.

14. Westrom G, Finstrom O, Stenport G. Umbilical artery catheterization in newborns: thrombosis in relation to catheter tip and

position. Acta Paediatr Scand. 1979;68:575.

15. Fleming SE, Kim JH. Ultrasound-guided umbilical catheter

insertion in neonates. J of Perinatology. 2011;31:344.

16. Baker DH, Berdon WE, James LS. Proper localization of umbilical arterial and venous catheters by lateral roentgenograms.

Pediatrics. 1969;43:34.

17. Weber AL, Deluce S, Shannon DL. Normal and abnormal position of umbilical artery and venous catheter on the roentgenogram and review of complications. AJR. 1974;20:361.

18. Mokrohisky ST, Levine RL, Blumhagen RD, et al. Low positioning of umbilical artery catheters increases associated complications in newborn infants. N Engl J Med. 1978;229:561.

19. Barrington KJ. Umbilical artery catheters in the newborn: effects

of position of the catheter tip. Cochrane Database Syst Rev.

2000;CD000505.

 

170 Section V ■ Vascular Access

b. Infection (38,64,65)

c. Necrotizing enterocolitis (34,53,54)

d. Intestinal necrosis or perforation (66)

(1) Vascular accident

(2) Infusion of hypertonic solution (67)

e. Transection of omphalocele (Fig. 29.22) (68)

f. Herniation of appendix through umbilical ring (69)

g. Cotton fiber embolus (70)

h. Wharton jelly embolus (71)

i. Hypernatremia

(1) True

(2) Factitious (60)

j. Factitious hyperkalemia (60)

k. Bladder injury (ascites) (31–33)

l. Curving back of the catheter on itself as a result of it

catching in the intima (72)

m.Pseudocoarctation of the aorta (52)

n. Pseudomass in left atrium (73)

o. Displacement by thoracoabdominal abnormality (74)

p. Failure to obtain a lateral x-ray to confirm position

of a percutaneous femoral central line. This failure

led to the failure to recognize that the line is displaced into a spinal vein; it was interpreted by the

radiologist as a correctly placed high umbilical

artery line. (Fig. 29.23)(40)

Fig. 29.21. Anteroposterior roentgenogram demonstrating air

embolism from a UAC in the left subclavian artery (upper arrow)

and the femoral arteries (lower arrows).

Fig. 29.22. Small omphalocele. This gut-containing hernia

was transected during placement of a UAC.

Fig. 29.23. Failure to obtain a lateral radiographic view to confirm the position of this percutaneously placed femoral central

venous line led to failure to recognize that the line is displaced

into a spinal vein. The line was reported by the radiologist as a correctly positioned high umbilical arterial line.

Chapter 29 ■ Umbilical Artery Catheterization 171

References

1. Kanarek SK, Kuznicki MB, Blair RC. Infusion of total parenteral

nutrition via the umbilical artery. J Parenter Enter Nutr. 1991;

15:71.

2. Rand T, Weninger M, Kohlhauser C, et al. Effects of umbilical

arterial catheterization on mesenteric hemodynamics. Pediatr

Radiol. 1996;26:435.

3. Clawson CC, Boros SJ. Surface morphology of polyvinyl chloride

and silicone elastomer umbilical artery catheters by scanning

electron microscopy. Pediatrics. 1978;62:702.

4. Hecker JF. Thrombogenicity of tips of umbilical catheters.

Pediatrics. 1981;67:467.

5. Boros SJ, Thompson TR, Reynolds JW, et al. Reduced thrombus

formation with silicone elastomer (Silastic) umbilical artery catheters. Pediatrics. 1975;56:981.

6. Jackson JK, Derleth DP. Effects of various arterial infusion solutions on red blood cells in the newborn. Arch Dis Child Fetal

Neonatal Ed. 2000;83:F130.

7. Rajani K, Goetzman BW, Wennberg RP, et al. Effects of heparinization of fluids infused through an umbilical artery catheter on

catheter patency and frequency of complications. Pediatrics.

1979;63:552.

8. Ankola PA, Atakent YS. Effect of 

 

168 Section V ■ Vascular Access

A B

Fig. 29.16. Effect of abdominal mass stimulating catheter misplacement. Anteroposterior (A) and lateral (B) films show remarkable displacement of a UAC by a giant hematocolpos in a 1-day-old infant.

Fig. 29.17. Vascular compromise in the left

buttock and loin owing to a complication of a

UAC displaced into the internal iliac artery.

For vascular anatomy, see Fig. 29.4.

Chapter 29 ■ Umbilical Artery Catheterization 169

Fig. 29.20. Generalized mottling of skin in infant with severe

hypertension secondary to UAC-associated thrombus in renal

artery.

Fig. 29.19. Autoamputation of forefoot, owing to vascular complication of a UAC.

A B

Fig. 29.18. Arrows indicate mural thrombus in the abdominal aorta, which was associated with an

umbilical arterial line. Upon further dissection of this autopsy specimen, the left renal artery was found to

be occluded by thrombus. The left kidney is showing a degree of atrophy. Both kidneys showed scattered

infarction.

 

Fig. 29.15. Anteroposterior (A) and lateral (B) radiographs demonstrating passage of a UAC into the

pulmonary artery via a patent ductus arteriosus.

a. Umbilical tape must be tied on skin rather than

Wharton jelly.

b. Catheter has been in situ for longer than 48 hours,

because artery may have lost ability to spasm.

2. Withdraw catheter slowly and evenly, until approximately 5 cm remains in vessel, tightening purse-string

suture or umbilical tie.

3. Discontinue infusion.

4. Pull remainder of catheter out of the vessel at rate of

1 cm/min (to allow vasospasm). If there is bleeding,

apply lateral pressure to the cord by compressing

between thumb and first finger.

J. Complications (38–41)

Catheterization of the umbilical artery is probably always

associated with some degree of reversible damage to the

arterial intima (42,43).

1. Malpositioned catheter (Figs. 29.14–29.16)

a. Vessel perforation (44)

b. Refractory hypoglycemia with catheter tip opposite

celiac axis (45)

c. Peritoneal perforation (46)

d. False aneurysm (47)

e. Movement of catheter tip position because of

changes in abdominal circumference

 

166 Section V ■ Vascular Access

7. Catheter-related vascular compromise

8. Onset of platelet consumption coagulopathy

9. Peritonitis

10. Necrotizing enterocolitis

11. Omphalitis

C D

A B

Fig. 29.14. Various UAC malpositions. A: Unacceptable position at L2 because of the proximity

of the renal arteries. B: UAC in left brachycephalic artery. C: UAC in right brachycephalic artery.

D: UAC in pelvic artery.

Technique

1. Leave umbilical tie loose around cord stump as precaution against excessive bleeding.

Reinsertion of purse-string suture through dried

Wharton jelly is preferable if

Chapter 29 ■ Umbilical Artery Catheterization 167

f. Sciatic nerve palsy (48)

g. Misdirection of catheter into internal or external

iliac artery (see Figs. 29.14D and 29.17) (39).

Schreiber et al. (42) have described a doublearterial catheter technique to correct this problem.

2. Vascular accident

a. Thrombosis (Fig. 29.18) (49–52)

b. Embolism/infarction (Fig. 29.17) (17,27) seen days

or weeks after line insertion (38)

c. Vasospasm (17,38,53,54) is seen within minutes to a

few hours after insertion.

d. Loss of extremity (Fig. 29.19) (53)

e. Hypertension (Fig. 29.20) (18,55)

f. Paraplegia (56)

g. Congestive heart failure (aortic thrombosis) (57)

h. Air embolism (Fig. 29.21)

3. Equipment-related

a. Breaks in catheter and transection of catheter (58)

b. Plasticizer in tissues (59,60)

c. Electrical hazard

(1) Improper grounding of electronic equipment

(2) Conduction of current through fluid-filled

catheter

d. Intravascular knot in catheter (61)

4. Other

a. Hemorrhage (including that related to catheter loss

or disconnection and overheparinization) (39,62,63)

A B

 

1. Gloves

2. Alcohol swabs

3. Rubber-tipped clamps or disposable IV tubing clamps

4. Syringe of 0.6 mL of flushing solution

5. Syringe for cleaning line

6. Syringe for blood sample

7. Ice, if necessary for sample preservation

8. Appropriate requisition slips and labels

Technique

1. Wash hands and put on sterile gloves.

2. Form sterile field.

3. Clean the connection site of the stopcock/catheter

using an alcohol swab.

4. Clamp the umbilical catheter.

5. Connect the 3-mL syringe, release the clamp, and

slowly draw back 2 to 3 mL of fluid over 1 minute to

clear the line. Reclamp the catheter. Remove syringe

and place on sterile field. Data published by Davies

et al. (36) indicate that accurate measurements of electrolytes can be obtained after withdrawal of a minimum

of 1.6 mL of blood. However, if blood glucose values

are desired, a minimum of 3 mL from a 3.5-Fr and

4 mL from a 5-Fr catheter must be withdrawn.

6. Attach sampling syringe. Release clamp and draw back

specimen desired. Reclamp the catheter.

7. Reattach the syringe containing the fluid and blood

cleared from the line.

a. Clear the connection of air.

b. Slowly replace the fluid and blood cleared from the

line and remove the syringe.

8. Attach the syringe of flushing solution to the stopcock,

clear air from the connection, and slowly flush the line.

9. Clean the stopcock connection with alcohol.

10. Record on infant’s daily record sheet all blood removed

and volume of flush used.

A study was carried out that looked at cerebral

oxygenation and blood sampling from UAC in high

position in preterm infants (median gestational age

30 weeks). Although the clinical significance is unclear,

the study showed that blood sampling of 2.3 mL

(including flush volumes) through the UAC within

20 seconds resulted in a significantly decreased cerebral oxygenated hemoglobin and tissue oxygenation

index. It also caused an increase in deoxygenated

hemoglobin. This was not seen when the sampling

time was extended to 40 seconds (37).

I. Removal of UAC

Indications

1. No further clinical indication

2. Need for less frequent direct PO2 measurements

3. Sufficient stabilization of blood pressure to allow intermittent monitoring

4. Hypertension

5. Hematuria not due to other recognizable cause

6. Catheter-related sepsis and/or infections with

Staphylococcus aureus, gram-negative bacilli, or Candida

mandate removal of the catheter (38)

 

Removal of Catheter

1. Remove any tape and withdraw catheter slowly, as

described earlier in this chapter.

2. If the internal ligature around a catheter is too tight to

allow removal with reasonable traction, it may be necessary to dissect and cut the ligature, after sterile skin

preparation.

Fig. 29.13. Subumbilical cutdown. Anatomic view through

incision. (Redrawn from Sherman NJ. Umbilical artery cutdown.

J Pediatr Surg. 1977;12:723, with permission.)

Chapter 29 ■ Umbilical Artery Catheterization 165

3. Apply pressure for hemostasis.

4. Approximate wound edges with skin-closure tape.

Complications

1. Catheterization of urachus (30)

2. Vesicoumbilical fistula (30)

3. Transection of urachus with urinary ascites (31)

4. Perforation or rupture (32,33) of urinary bladder—

although Nagarajan (33) has suggested that the risk of

bladder injury is minimal if bladder is emptied prior to

procedure.

5. Transection of umbilical artery with hemorrhage

6. Incision of peritoneum (with possible evisceration)

7. Bleeding from incision

G. Care of Dwelling Catheter

For setup and maintenance of arterial pressure transducer,

see Chapter 9.

1. Keep catheter free of blood to prevent clot formation.

a. Flush catheter with 0.5 mL of flush solution, slowly

over at least 5 seconds, each time a blood sample is

drawn.

b. Between samples, infuse IV solution continuously

through catheter to prevent retrograde flow.

c. Note amounts of blood removed and IV fluid/flush

solution infused, and add to fluid balance record.

2. Watch for indications of clot formation.

a. Decrease in amplitude of pulse pressure on blood

pressure tracing

b. Difficulty withdrawing blood samples

3. Take appropriate action if clot forms.

a. Do not attempt to flush clot forcibly.

Remove catheter. Replace only if critical.

4. Enteral feeding in the presence of UACs remains controversial. Increased risk of mesenteric thromboembolism and its association with the development of necrotizing enterocolitis has been suggested (34). Other

studies have shown no increased incidence of feeding

problems or complications in infants fed with a UAC

in situ (35).

H. Obtaining Blood Samples from

Catheter

(With emphasis on aseptic technique and minimizing stress

to the vessel)

Equipment

 

The vessels with their surrounding tissues appear

larger than expected. When elevated, there will be no

caudal bulge, distinguishing them from the urachus. If

a previously attempted catheter was left “in place,” palpation of the area allows more ready identification of

the vessel. Previously unsuccessful attempts, with failure to pass more than a few centimeters, are usually

associated with perivascular hematoma formation from

unrecognized perforation and dissection through a false

tract. Visualization of a hematoma helps distinguish the

vessel from the urachus.

12. Try to avoid entering the peritoneum. In infants with

very little subcutaneous tissue, it may be impossible to

avoid penetrating the peritoneum. Should this occur,

replace any bowel that may protrude and carefully

close the peritoneum with absorbable suture, taking

extreme care not to include any bowel within the

suture. Start antibiotics for peritonitis prophylaxis.

13. Insert the tip of the mosquito forceps under the vessel

and pull a doubled strand of plain absorbable suture

under the vessel. Position sutures 1 cm apart.

14. While elevating the sutures and with suture scissors

directed cephalad, make a V-shaped incision through

three fourths of the diameter of the vessel. Take care not

to transect the vessel, but cut cleanly into the lumen.

If the artery is accidentally transected and if the

catheter insertion is unsuccessful, tie off the caudal end

of the artery to prevent hemorrhage.

15. Use curved tissue forceps or a catheter introducer to

dilate the artery.

16. Pass the catheter through the opening for the predetermined distance, checking for blood return after a few

centimeters. The catheter should advance without

resistance.

17. When the catheter is properly positioned, have an assistant check the perfusion in the lower extremities. If that

is satisfactory, secure the catheter by tying the lower

ligature firmly around the catheter.

18. Using absorbable suture, close the fascia and approximate the subcutaneous tissues.

Hashimoto et al. (29) proposed an alternative technique that allows for catheter reinsertion in case of

catheter thrombosis or occlusion. They use loose ligation around the artery once the catheter is in proper

position. They then fix the artery by using the same

sutures that close the fascia, thus creating an arteriocutaneous fistula, making it easy to find the insertion site

and use it for reinsertion.

19. Close the skin with nonabsorbable suture or with skinclosure tape after cleaning the area.

20. The catheter may be further secured with a tape bridge

(Fig. 38.14).