Indian Pediatrics 1999;36: 914-917

Peripheral Vessel Exchange Transfusion

From the Department of Pediatrics, Karnatak Institute of Medical Sciences, Hubli 580 022, India and Vithal Clinic and Children's Hospital, Dharwad 580 008, India.
Reprint requests: Dr. Devaraj V. Raichur, Assistant Professor, Department of Pediatrics, Karnatak Institute of Medical Sciences, Hubli 580 022, India.
Manuscript received: October 9, 1998;
Initial review completed: December 11, 1998;
Revision accepted: April 19, 1999

Nearly a decade ago peripheral vessel exchange transfusion (PVET)_drawing blood from a peripheral artery and infusing through a peripheral vein_was proposed to be consi-dered for all infants requiring exchange transfusion (ET) to avoid the various complications associated with the use of umbilical vessels for ET(1). However, none of the later works published in English literature used PVET as a method of choice in all of their babies requiring double volume exchange transfusion (DVET) except in one baby(2). We conducted a study to verify if PVET could successfully be employed for all cases needing ET, as a method of choice, especially in a set-up where transillumination by a fibre-optic light(3) is not available to aid arterial cannulation.

Subjects and Methods

From September 1997 to August 1998, we performed ET in 31 neonates through peripheral vessels. The gestational age of the neonates ranged from 30 weeks to 41 weeks (mean 36.5  weeks). Eighteen neonates were preterm and 13 neonates were term babies. Birth weight of the babies ranged from 1.1 kg to 3.3 kg (mean: 2.145 kg). Indications for ET included `hyperbilirubinemia only' in 15 cases, `septi-cemia only' in 4 cases and `septicemia with hyperbilirubinemia' in 11 cases. In one baby which presented with a septicemia like clinical picture, ET was done to tide over the crisis due to supsected inborn error of metabolism. Consent was taken from parents in all cases before performing the ET.

In all babies, after Allen's test(4) to confirm adequate collateral circulation, one of the radial arteries was tried for cannulation, for drawing blood, as the first choice. If this failed, the other side was tried after Allen's test. If radial artery cannulation failed on both the sides, one of the superficial temporal arteries or their terminal branches (parietal or frontal) was tried as an alternative. Percutaneous technique was used in all the cases for arterial cannulation. We did not use transillumination with a fibre-optic light to aid cannulation as this facility was not available.

In each case the artery was cannulated with a 24 gauge cannula and blood was drawn from the artery and discarded intermittently by one person through a 3-way tap in aliquots of 2 ml each and simultaneously equal volume of blood was replaced through a peripheral vein using a 22 or 24 gauge cannula by another person.The arterial line was flushed with 0.5 ml heparinized (5 units/ml) isotonic saline, over 5 to 10 seconds, after withdrawal of every 50 ml of blood. The arterial cannula was removed soon after the procedure in each case.

DVET was performed in all babies, except in 2 septicemic babies where single volume ET was done due to their unstable condition before starting the ET.

All surviving neonates were reviewed at the age of 6 weeks. In addition, those who had cannulation of superficial temporal artery were called for review at the age of 6 months.

Results

Of the 31 newborns in the study, cannulation of one of the radial arteries was successful in 25 babies and failed in 6 babies. The latter included 3 babies with sclerema and 3 term babies who were vigorously struggling. These babies were easily cannulated in superficial temporal artery. In one newborn where initially radial artery was cannulated, the arterial line failed to drain blood midway during the pro-cedure and in this case a superficial temporal artery was cannulated successfully and the ET was completed. In no babies in whom superficial temporal artery cannulation was attempted, the procedure failed. All the superficial temporal artery cannulations were required only during the first half of the study period. During the second half, attempts at radial artery cannulation were always successful.

In the study, we measured pre-exchange and post-exchange serum bilirubin levels in 10 of the cases with indirect hyperbilirubinemia. The fall in indirect bilirubin in post-exchange serum ranged from a value of 31.9% to 82.3% of the pre-exchange level (mean: 49.2%).

The duration of the procedure for DVET where only one artery was used for drawing blood throughout the procedure ranged from 60 to 180 minutes (mean: 109 minutes). Cannulation of the radial artery yielded relatively more fluent aspiration of blood (range: 60-170 minutes and mean: 106 minutes) than the superficial temporal artery (range: 90-180 minutes and mean: 122 minutes).

No baby had mortality during or within 12 hours of completing ET. Five of the septicemic neonates expired at a varying period after 12 hours. The baby with suspected inborn error of metabolism expired after 14 hours.

None of the babies had complications related to arterial cannulation except insignificant hematoma, though 3 babies required pressure on the artery for more than 10 minutes (15, 20 and 40 minutes, respectively) for the arterial leak to stop after removing the cannula. None of the babies in `hyperbilirubinemia only' group had sepsis during the period after ET till discharge from the neonatal unit.

At follow-up, all the babies who survived were normal, clinically, including neurological examination. Of the 7 babies who had temporal artery cannulation, one expired 3 days after the ET, one was lost to follow-up at 6 months and the remaining five were normal clinically (including neurological examination) at the age of 6 months.

Discussion

Although the complications of ET through umbilical vessels and the advantages of PVET in preventing such complications are well documented(1,2), the use of arterial catheters is not without risks. It has been observed, when arterial catheters were used for other indications, that cerebral embolism is possible by a clot originating from a catheter in radial artery(5-7) or in temporal artery(8-10). In addition, a rapid flush of the arterial catheter can elevate blood pressure and lead to intraventricular hemorrhage(11). These events occur when there is a significant retrograde flow along the artery, while flushing the catheter. Later investigators have used cannulae in various arteries_including radial and temporal arteries_by taking care to avoid such a retrograde flow(12).

To prevent thrombotic, embolic and intracranial complications due to PVET, we suggest the following precautions in relation to the arterial cannula, during the procedure: (i) As small cannula (in diameter and length) as practicable should be used(7,13); (ii) Cannulation should be done percutaneously rather than by a cutdown(14); (iii) Stasis of blood in the cannula should be prevented as it is an important factor for formation of a thrombus or clot; (iv) Entry of air into the artery should be prevented by promptly removing air bubbles, if any, from the cannula(3); (v) The isotonic saline used for flushing the cannula should be heparinized(9); (vi) Volume of the flush-solution should be kept as small as possible(6,7); (vii) Rate of flushing should be so controlled that local skin blanching does not occur(6,12). This prevents a significant retrograde flow. A suggested rate is 0.5 ml over 5 to 10 seconds; (viii) The cannula should be kept in place for as short duration as possible(7,14); (ix) If for some reason the cannula gets obstructed, it should be replaced with a fresh one, at a different site. A forceful flush to overcome the obstruction should not be attempted as such practice can result in embolism(7); and (x) The cannula should be placed as distant as possible from the cerebral circulation. We selected superficial temporal artery after failing to cannulate the radial arteries because, cannulation of the ulnar artery should be avoided if the radial artery of the same side has been punctured already(12) and, in our experience prior to the study-period, without transillumination cannulation of posterior tibial artery or dorsalis pedis artery is extremely difficult with very low success rates. However, we suggest that the latter two arteries should be preferred (when one of them has not already been punctured on the same side) over superficial temporal artery if fibre-optic light is available for transillumination.

Possibly, the difficulty in cannulation of arteries is the main reason why PVET has not been as popular among pediatricians as it deserves(1,2). Although transillumination by a fibre-optic light has improved the success rate in arterial cannulation, it is not available to most pediatricians caring for the neonates requiring ET. Cannulation of the arteries needs some skill and one can become adroit in the same by experience, as noted by us that during the second half of the study period, one of the radial arteries was cannulated successfully in all cases.

Our experience shows that it is possible to use PVET, with proper precautions, as a method of choice even when fibre-optic light is not available to facilitate arterial cannulation, with relatively little risk, thus avoiding the severe complications related to ET through umbilical vessels.

Acknowledgement

We thank the Director and the Principal, KIMS, Hubli and the Chief Pediatrician, Vithal Clinic and Children's Hospital, Dharwad for permitting to publish this study.

References

1. Fok TF, So LY, Leung KW. Use of peripheral vessels for exchange transfusion. Arch Dis Child 1990; 65: 676-678.

2. Merchant RH, Sakhalkar VS, Rajadhyaksha SB. Exchange transfusions via peripheral vessels. Indian Pediatr 1992; 29: 457-460.

3. Cole FS, Todres ID, Shannon DC. Technique for percutaneous cannulation of the radial artery in the newborn infant. J Pediatr 1978; 92: 105-107.

4. Allen EV. Thromboangitis obliterans: Methods of diagnosis of chronic occlusive arterial lesions distal to the wrist with illustrative cases. Am J Med Sci 1929; 178: 237-244.

5. Gaan D, Mallick NP, Brewis RAL, Seedat YK, Mahoney MP. Cerebral damage from declotting Scribner shunts. Lancet 1969; 2: 77-79.

6. Lowenstein E, Little JW, Lo HH. Prevention of cerebral embolization from flushing radial-artery cannulas. N Engl J Med 1971; 285: 1414-1415.

7. Downs JB, Rackstein AD, Klein ET, Hawkins IF. Hazards of radial-artery catehterization. Anesthesiology 1973; 38: 283-286.

8. Simmons MA, Levine RL, Lubchenco LO, Guggenheim MA. Warning: Serious sequelae of

temporal artery catheterization. J Pediatr 1978; 92: 284.

9. Prian GW, Wright GB, Rumack CM, O'Meara OP. Apparent cerebral embolization after temporal artery catheterization. J Pediatr 1978; 93: 115-118.

10. Bull MJ, Schreiner RL, Garg BP, Hutton NM, Lemons JA, Gresham EL. Neurologic complications following temporal artery catheterization. J Pediatr 1980; 96: 1071-1073.

11. Butt WW, Gow R, Whyte H, Smallhorn J, Koren G. Complications resulting from use of arterial catheters: Retrograde flow and rapid elevation in blood pressure. Pediatrics 1985; 76: 250-254.

12. Randel SN, Tsang BHL, Wung J, Driscoll JM, James LS. Experience with percutaneous indwelling peripheral arterial catheterization in neonates. Am J Dis Child 1987; 141: 848-851.

13. Wyatt R, Glaves I, Cooper DJ. Proximal skin necrosis after radial-artery cannulation. Lancet 1974; 1: 1135-1138.

14. Miyasaka K, Edmonds JF, Conn AW. Complications of radial artery lines in the pediatric patient. Can Anaesth Soc J 1976; 23: 9-14.