Saline May Be as Effective as Heparin in Pediatric Central Venous Catheter Flush

Dee Ann Omatsu, MS, APRN, PNP-BC, CPON

Following an intervention which found that saline flush had comparable safety and efficacy with heparin for tunneled catheters used in pediatric patients with cancer, a formal flushing guideline advising lower heparin concentrations and increased saline use was issued in Kapi‘olani Medical Center for Women and Children (KMCWC) institution. Results of the guideline change were published in the Clinical Journal of Oncology Nursing.¹

“This limited process improvement project was able to show the effectiveness and safety in the use of normal saline flushing and decreased heparin dose flushes to maintain tunneled [central venous catheter] CVC patency in the population of pediatric patients with cancer,” lead author Dee Ann Omatsu, MS, APRN, PNP-BC, CPON®, a nurse practitioner with Hawaii Pacific Health, and coinvestigators, wrote in the study. “This was evidenced by no statistically significant change in alteplase use recorded postimplementation. The decreased use of heparin resulted in cost savings for patients and families.”

CVCs are a key component in delivering long-term intravenous (IV) therapy to children with cancer. These devices are responsible for a variety of treatments, including parenteral nutrition, chemotherapy, and blood product infusions; however, for fluid infusions and blood draws, adequate CVC patency without catheter occlusions is required. Alteplase administration is the appropriate response when occlusion occurs. In certain cases of occlusion, the CVC may need to be removed.

Numerous studies have documented the efficacy of saline flush use in adults.^2-4 Yet there is insufficient literature detailing its efficacy and utility among pediatric patients. Heparin is a more expensive medication compared with saline⁵ and intermittent flushing with heparin throughout the day can place additional financial burden on the patient’s family because it is a medication that is not frequently covered by insurance.⁶ Thus, investigators sought to reduce the financial burden on patients if saline represented a viable option.

This study included 62 patients, of whom 42% were women and the mean age was 9.42 years. The 3 most common diagnoses among the study group were acute lymphoblastic leukemia (ALL; n = 15, 24%), osteosarcoma (n = 6, 10%), and T-cell ALL (n = 5, 8%). Eleven percent of patients (n = 7) were receiving were Children’s Oncology Group protocols AALL0932, 8% (n = 5) were receiving AALL1131, and 8% (n = 5) were receiving AOST0331.

Prior to the intervention, the institutional flushing guide included heparin administration for all tunneled lines, at a concentration 100 units/cm3 and various amounts depending on the weight of a patient and the type of device. However, a saline lock for all tunneled lines was added to the flushing guidelines as part of the implementation.

In the inpatient setting, a twice-daily schedule using the new push–pause method was implemented. In the outpatient setting, nurses locked the tunneled lines with saline using the push–pause method if their patient was actively receiving care in the unit. Saline lock was also used if patients needed daily infusion regiments and elected to keep their port needle in place.

The heparin lock changes were implemented at time of discharge of the port or deaccess of the external tunneled catheters. Although the port dosage remained the same with 5 ml (100 units/ mL), the implementation meant that the heparin dose decreased from 3 ml (100 units/mL) to 2 mL (10 units/mL) for tunneled catheters. Study interventions began on September 1, 2020, and data were collected over 5 months, with a cutoff at February 1, 2021.

Overall, the mean alteplase usage rate following implementation of saline flush was not statistically significant than with heparin flush after adjusting for age and sex (P = .89). In the preintervention heparin flush period, the mean alteplase usage rate was 2.17 per 2000-line days. The shift to heparin found a slight increase to 2.42 per 1000-line days. Of note, following the implementation, the cost per single lumen, a 30-count box of heparin (10 units/mL) 5 mL syringe, decreased from $520.20 to $366.24.

Providers may be able to safely decrease heparin use and opt for normal saline flush to maintain CVC patency, effectively reducing costs for patients and families, the authors concluded, noting that it is essential that nurses use the positive pressure lock and push-pause techniques.

References

1. Omatsu D, Thompson K, Maglasang B, Yuasa H, Kimata C. Heparin versus normal saline: flushing effectiveness in managing central venous catheters in pediatric patients with cancer. Clin J Oncol Nurs. 2022;26(3):300-307. doi:10.1188/22.CJON.300-307
2. Sharma SK, Mudgal SK, Gaur R, Sharma R, Sharma M, Thakur K. Heparin flush vs. normal saline flush to maintain the patency of central venous catheter among adult patients: A systematic review and meta-analysis. J Family Med Prim Care. 2019;8(9):2779-2792. doi:10.4103/jfmpc.jfmpc_6
3. Zhong L, Wang HL, Xu B, et al. Normal saline versus heparin for patency of central venous catheters in adult patients - a systematic review and meta-analysis. Crit Care. 2017;21(1):5. doi:10.1186/s13054-016-1585-x
4. López-Briz E, Ruiz Garcia V, Cabello JB, Bort-Martí S, Carbonell Sanchis R, Burls A. Heparin versus 0.9% sodium chloride locking for prevention of occlusion in central venous catheters in adults. Cochrane Database Syst Rev. 2018;7(7):CD008462. doi:10.1002/14651858.CD008462.pub3
5. Bradford NK, Edwards RM, Chan RJ. Normal saline (0.9% sodium chloride) versus heparin intermittent flushing for the prevention of occlusion in long-term central venous catheters in infants and children. Cochrane Database Syst Rev. 2020;4(4):CD010996. doi:10.1002/14651858.CD010996.pub3
6. UnitedHealthcare Medicare Advantage. UnitedHealthcare Medicare Advantage Coverage Summary: Medication drugs (Outpatient/Part B). United Healthcare Services Inc. Accessed July 13, 2022.