Direct cost of maintenance of totally implanted central venous catheter patency

ABSTRACT Objective: to identify the average direct cost of maintaining the patency of totally implanted central venous catheter with heparin at a Day Hospital of a public hospital of high complexity specialized in the treatment of cancer patients, and estimate the average direct cost of replacing heparin with sodium chloride 0.9%. Method: quantitative, exploratory-descriptive study, with a sample of 200 non-participant observations of the maintenance of totally implanted central venous catheters with heparin. The average direct cost was calculated by multiplying the (clocked) time spent by professionals to complete the procedure by the direct unit cost of workforce, added to the cost of materials and solutions. Results: the estimated total direct cost of catheter maintenance with heparin was US$ 9.71 (SD=1.35) on average, ranging from US$ 7.98 to US$ 23.28. The estimated total direct cost of maintenance with 0.9% sodium chloride in the place of heparin was US$ 8.81 (SD=1.29) on average, resulting in a reduction of US$ 0.90 per procedure. Conclusion: the results contributed to propose strategies to assist in cost containment/minimization in this procedure. The replacement of heparin by 0.9% sodium chloride proved to be an option to reduce the total average direct cost.


Introduction
Oncological treatment requires periodic actions to maintain the patency of totally implanted central venous catheter (CVC-TI), a safe and effective device for intravenous chemotherapy, and to maintain the integrity of the venous network of the patient (1)(2) . This procedure can be performed with heparin or 0.9% sodium chloride (1)(2) , and requires qualified human resources and specific materials whose costs are unknown by health organizations and the professionals responsible for carrying out the process. Such lack of knowledge may compromise the decision-making process when it comes to efficient resource allocation, in the sense of minimizing costs without impairing the quality of the assistance provided.
Increasing costs have called the attention of hospital managers, health professionals and payers of care, especially in hospital areas with considerable expenses and at the same time scarce financial resources, which increases the emphasis on cost control (3) .
Nursing professionals represent a significant part of the staff in health organizations and it is up to them to make decisions regarding structure, processes, human resources and institutional outcomes. Therefore, knowledge of the costs associated with the provision of nursing services may support their qualified participation in redefining priorities, rationalizing limited resources and monitoring productivity (4) .
Considering that nurses have been responsible for the coordination of health care teams, units/sectors/ services or even material management, it is imperative that they acquire knowledge regarding health costs (5) .
In view of the relevance of the procedure discussed here, in order to ensure the feasibility of chemotherapy treatment to cancer patients, it is worth noting that knowledge on incurred costs may help in the decisionmaking process, allowing cost control. The objective of this study was to identify the average direct cost of maintenance of CVC-FI patency with heparin at the Day Hospital of a highly complex public hospital specialized in the treatment of cancer patients and to estimate the average direct cost of replacement of heparin by 0.9% sodium chloride for maintaining CVC-TI patency.  the possibility of identification with the product or department. It refers to the costs that can be identified and quantified (6) , mainly represented by costs with direct workforce, materials, drugs, solutions and equipment used in the care process.

Method
Direct workforce comprises the personnel who work directly on a product or service provided, whose work time can be measured and identity at individual level can be known. Costs involve salaries, social charges, holiday provisions, and 13th salary (6) .
The cost of the direct nursing professional workforce was calculated based on the average salaries (salary, benefits, gratifications, and social charges) per category : The C P l mat The C P l sol ( ) is obtained by summing the average costs Cs k     of each solution/drug consumed (7) : Therefore, the C P l sol By replacing equation (9) in the equation (8) Finally, by replacing equations (4), (7) and (10) in the equation (1), we obtain equation (11) (7) :

Results
During the period of data collection, all nursing professionals at the Day Hospital, from shifts A and B, who     Table 5.

Discussion
The first step of CVC-TI heparinization, "collection of material in the MAC at the 11th floor", was mainly It was also pointed out that secondary and tertiary health care institutions use a greater quantity of drugs and other supplies, and thus the use of a unit dose drug distribution system at these levels could represent a greater opportunity for savings (9) .
In the second step, "material preparation and asepsis", the cost with material was significantly higher to the profession and care (14) .
The third and fourth steps of the procedure, namely, "puncture and CVC-TI heparinization" and "disposal of material", showed lower average total direct costs than the previous steps and was determined by the cost with the nurse workforce.
We reiterate the need for calculating the direct costs incurred by procedures carried out by nursing professionals, as well as providing an analysis of the consumption of resources to their feasibility and financial impact, so as to provide information to enable the adjustment of supplies and indicate possibilities for improvement in their implementation (4) .
In different work processes, nurses take on the task of supervising the teams under their responsibility, Among these assignments, it is important to note the indispensability of their participation in raising awareness among professionals about the rationalization of expenditures, aiming at minimal waste of resources and commitment with the assistance provided (15) .
It was observed in this study, that the use of some materials in larger quantities than the stipulated, or non-supply of some material (additional material) in the clinical protocol of CVC-IT heparinization, even though without significant costs, indicates the opportunity to sensitize nurses to prevent/minimize waste.
Maintenance of the patency of CVC-IT, as previously mentioned, can be done by replacing heparin with sodium chloride 0.9%. Both have the same purpose and effectiveness, but sodium chloride 0.9% has the advantage of being safer, without anticoagulant-related risks (1)(2) . A systematic review in 2015 showed that the concentration of heparin alone is not associated with the improvement of central venous catheter patency rates. Furthermore, its systemic effects may cause a problem as they contribute to the development of thrombocytopenia. In contrast, the use of sodium chloride 0.9% has been considered adequate, without significant differences in effectiveness when compared with heparin, and posing a lower risk of complications to the patients (16) .
Therefore, in addition to the scientific evidence available in the literature regarding the benefits of using 0.9% sodium chloride for CVC-IT patency maintenance, the results of the present study provide evidence of economic advantages of using saline solution in the place of heparin. It brings the possibility of cost savings without compromising the quality of the procedure and patient safety.
Finally, we agree that because of their high complexity, health institutions need to adopt economic, managerial and financial instruments to its administration, seeking to offer better budget control and generate gains in terms of efficiency and effectiveness. The use of cost per procedure is a useful method to establish the average price of each health procedure, estimating costs for trading of packages, as well as to contribute to the determination of profitability by stimulating cost control and reduction (17) .

Conclusion
The average direct total cost of CVC-TI heparinization was US$9.71 (SD=1.35), ranging from US$7.98 to US$23.28, with a median and mode of US$9.51.
Since scientific data supports the use of 0.9% sodium chloride for maintenance of CVC-TI patency, the simulation of its use in place of heparin indicated that no additional material would have to be included in the procedure, and the withdrawal of 20 ml syringes and a 0.9% sodium chloride ampoules would have an average direct total cost of US$8.81 (SD=1.29), achieving a reduction of US$0.90/procedure by the use of salinization.
Although the benefits of 0.9% sodium chloride have been identified for the maintenance of CVC-TI patency, the use of heparin is still common in several health organizations. Therefore, it is expected that the economic outcomes may represent a consistent evidence for nurses, in their spheres of governability, to subsidize their arguments to change the clinical practice, aiming at achieving better patient outcomes and the efficient resource allocation.