Continuous quality improvement in vascular access for hemodialysis
(Portuguese PDF version)

Fábio Linardi,1 José Luis Bevilacqua,2 José Francisco Moron Morad,3 José Augusto Costa4

1. Ph.D. Assistant professor, Department of Surgery, School of Medicine, Pontifícia Universidade Católica de São Paulo, Sorocaba, SP, Brazil.
2. Nephrologist, Dialysis Center, Hospital Evangélico de Sorocaba and Renal Therapy Service, Sorocaba, SP, Brazil.
3. M.Sc. Assistant professor, Department of Morphology, School of Medicine, Pontifícia Universidade Católica de São Paulo, Sorocaba, SP, Brazil.
4. Full professor, Department of Surgery, School of Medicine, Pontifícia Universidade Católica de São Paulo, Sorocaba, SP, Brazil.

Correspondence:
Fábio Linardi
Av. São Paulo, 2918, Jd. Gonçalves
CEP 18013-004 - Sorocaba, SP
Brazil
Tel.: +55 (15) 227.1612
Fax: +55 (15) 233.2833
E-mail: flinardi@terra.com.br

ABSTRACT

Objective: To present the elaboration and accomplishment of a program of continuous quality improvement for hemodialysis vascular access in 23 dialysis centers.

Method: From September 1998 to September 1999, the author visited and evaluated 23 dialysis centers located in seven Brazilian states, as a consultant physician of the Renal Therapy Service. During that period, all the aspects related to the vascular access for hemodialysis such as preparation, maintenance and utilization were assessed and a program based on continuous quality improvement was created and introduced in the centers after October 1999. In 2000, all the centers were assessed again.

Results: After visiting all the 23 centers and reviewing the literature, a continuous quality improvement program was created and implanted. The program focused on the Brazilian reality and was based on three basic concepts: 1) vascular access protection; 2) multidisciplinary team; and 3) experienced health care team. After 1 year of implementation, we verified a 5% decrease in catheterization of the subclavian vein (47.13 to 42.35%), and all units counted on the professional work of a health care team.

Conclusions: We conclude that the introduction of a continuous quality improvement program is very important for better results in maintenance, utilization and quality of hemodialysis vascular access.

Key-words: vascular access ports, renal dialysis, arteriovenous fistula.
Palavras-chave: vias de acesso vascular, hemodiálise, fístula arteriovenosa.

J Vasc Br 2004;3(3):191-6

Hemodialysis vascular access is a major cause of hospital admission in chronic renal patients in the U.S., accounting for 25% of the admissions in the first year of treatment and for 11% starting on the second year of hemodialysis, generating an yearly financial burden of more than 1 billion dollars.1

Such a high cost has been attributed to the high rate of arteriovenous fistula (AF) construction with interposition of an expanded polytetrafluoroethylene (PTFE) graft, which was reported to be as high as 85% in the southeastern US.2

In view of the situation, since 1995 several investigators have proposed programs for continuous quality improvement (CQI) of vascular access.3-10 The aim of CQI is to promote teamwork and early diagnosis of stenosis, and especially to decrease the use of PTFE.

In 1997, the National Kidney Foundation, through the Dialysis Outcomes Quality Initiative,3 elaborated a clinical guide which suggested that the use of PTFE grafts for hemodialysis vascular access should be decreased in 50%.

In 2000, Sesso11 presented data concerning vascular access in Brazil, showing that a PFTE graft was used in only 2% of patients.

In 2002, Linardi12 showed that in 2,559 patients from 23 hemodialysis units across seven Brazilian states, a PTFE graft was used in 3.2%. In these units, the cost of vascular access procedures accounted for 1% of the total operating cost.

Taking into consideration the different realities, the CQI programs for vascular access created in the U.S. would not be adequate for the Brazilian scenario. Thus, the development of a specific program addressing relevant issues in Brazil would be important.

After auditing 23 hemodialysis units and assessing their difficulties in terms of vascular access, a CQI program for vascular access in hemodialysis patients was proposed and implemented. This process is described below.

METHOD

In September 1998, the author of the present article was invited by Renal Therapy Service (RTS), a multinational hemodialysis company, to act as a consultant for hemodialysis vascular access. The work was to be carried out in 23 dialysis units to which the company was associated, distributed in seven Brazilian states.

RTS offers administrative guidance for hemodialysis units and has a Medical Advisory Board (MAB) which provides orientation (routine or on request) concerning relevant clinical aspects.

Within one year, all 23 units were visited. The visits were organized as follows:

  • interview with the clinical director and nurse in charge of the unit;
  • visit to the patients;
  • lecture for technicians; and
  • general meeting with nurses, nephrologists and surgeons.
During the interview, surgical and technical aspects and the supporting facilities were evaluated.

Concerning the surgical procedure, the following points were assessed: type of professional relationship between the unit and the surgical team (paid services or cooperation); mean time between the request and the construction of the access; postoperative follow-up and involvement of the surgeon with overall issues concerning the access.

The technical aspects discussed included antisepsis protocol, puncture technique, puncture distance, postdialysis needle site compression and the general knowledge of professionals about vascular access.

In relation to the supporting facilities, the points evaluated included the unit's location (in-hospital or not) and the location of the surgical vascular access procedure (in the unit or in a hospital surgical center).

During the visit to the patients, technical aspects concerning the handling of vascular access were discussed. Data were collected concerning the type and dysfunction of the access employed at that moment. Type of access was categorized as:
  • catheter or AF;
  • type of catheter - long or short-term;
  • catheter insertion site - femoral, subclavian or jugular vein;
  • type of AF - distal, proximal, interposition prosthetic graft, interposition saphenous vein graft, or lower-extremity saphenous vein transposition.
The lecture to technicians aimed at training these professionals in all aspects related to vascular access.

The focus of the general meeting with nurses, nephrologists and surgeons was the preparation of a general protocol for vascular access.

Relevant data

Surgical aspects

The main problems reported were the length of time between the request for vascular access and the performance of the procedure and the lack of involvement on the part of the surgeon in relation to postoperative follow-up.

In 17 cases, the surgical team provided paid services to the unit, and in six cases a cooperative relationship was in place. In the units with paid surgical services, the mean time between the request and the performance of the access procedure was 1 week; in the other units, it was 3 weeks. The involvement of the surgical team was better in units with paid services. The units with more than one surgical team had more problems than the units working with one single team. The most frequent problems observed in this case were the competition among teams and the different conducts followed in terms of the creation, maintenance and handling of vascular access.

Technical aspects

The lack of a protocol and conflicting information from nephrologists, surgeons and the nursing team were the most relevant problems.

Supporting facilities

There were eight in-hospital units and 15 satellite units. From the 23 units, five had a surgical room in which the access procedure was carried out.

The surgical teams had specific training in vascular surgery in 19 units, in heart surgery in three and in general surgery in one unit.

During the visit, 2,559 patients were evaluated. The most relevant observation was that subclavian catheters were employed in 47.13% of the cases.

In the presence of a radiocephalic AF, the distance between the punctures in the arterial and intravenous lines was in some cases 25 cm, with the first puncture in the forearm and the second in the arm.

RESULTS

After visiting all the units and observing the difficulties encountered, a CQI program was developed. It was based on three principles: 1) sparing extremity vessels; 2) working with a multidisciplinary team; and 3) employing paid surgical services.

Sparing vessels

Role of nephrologists

  • Initial guidance concerning peripheral vessels: guidance provided by the nephrologist to the chronic renal patient concerning extremity vessels at the pre-dialysis stage, so as to avoid puncture of major vessels during collection of blood for tests and drug infusion. This also prevents the deterioration of upper extremity superficial veins.
  • Indications for early access: The indication to perform internal vascular access for hemodialysis occurs when endogenous creatinine clearance reaches 10 ml/min in non-diabetic patients and 20 ml/min in diabetic patients. These values indicate that patients will need to start dialysis within 3 months.13 Creating the access before the beginning of dialysis is extremely important, since this measure prevents the need for a central venous catheter during the first dialysis sessions, decreasing the risks inherent to this type of procedure, as well as the cost.
  • Double lumen catheters: in urgent cases, a double lumen catheter must be used, and the access route for these catheters is a fundamental aspect to be considered. The following routes were proposed: internal jugular vein, subclavian vein, and femoral vein. The subclavian vein should be used if access to the jugular vein is unavailable. Double lumen catheters should be used for a maximum of three weeks to prevent vein stenosis.14
Role of the surgeon

Good vascular access is that which allows an arterial flow of at least 300 ml/min, two punctures with large caliber needles (16G) and venous return pressure below 80 mmHg.

The surgeon who intends to create hemodialysis vascular access must be familiar with these basic concepts and their relationship with hemodialysis sessions. Creating an AF is not the same as creating a vein-to-artery anastomosis to produce a loud and continuous murmur.

An ideal AF, as described by Ryan & Dennis15 in 1990, is long and superficial, allowing several puncture points with good distance between them; spares vessels for possible future construction; ensures comfort for patients during hemodialysis sessions; has a high degree of permeability and a low complication rate.

The best AF was considered to be that constructed at the wrist, employing the radial artery and the cephalic vein. Therefore, it is essential that the surgeon try the radio-cephalic AF as the first choice.

It is not always possible to perform a radio-cephalic AF, due to several reasons, such as co-morbidities, unavailability of vessels, and artery diseases, among others. Thus, it is important that the surgeon be aware of all the possible anatomical sites for the construction of a direct AF, avoiding, whenever possible, the use of synthetic prostheses.

To reach this objective, the surgeon must patiently examine the arterial pulses and superficial veins of upper extremities. If the clinical examination is not conclusive, the surgeon must request imaging tests, which can help in the correct identification of vessels to be used for AF construction.

The surgeon must also be familiar with the diagnosis and treatment of vascular access dysfunction, since it is the surgeon's responsibility to act on and solve any complications that may occur.

Role of the nursing team

A sterilization and anti-sepsis protocol was elaborated for patients and all the professionals that handle vascular access.

Also discussed were the technique for puncture and postdialysis needle compression, important aspects in terms of loss of access.

The site of puncture indicated in our program is located 5 cm above the arterial anastomosis and 5 cm from the venous line, sparing the proximal veins, which will be available for future constructions.

Multidisciplinary team

Usually, the professionals who have direct contact with the patient and who handle the vascular access everyday are technicians and nurses. Therefore, those professionals were trained to evaluate and diagnose all the changes that may affect vascular access.

A continuous education program was assembled for these professionals with the aim of training them to identify a poor functioning access. The continuous education program emphasizes specific variables that allow the early diagnosis of dysfunction, such as arterial flow, venous pressure, difficulty in performing the puncture, punctures that are too close by and early dilation of the vein.

The main objective was to prepare all the professionals for the early diagnosis of complications in vascular access, especially stenosis, which is the main cause of aneurysm formation and access thrombosis. The early diagnosis of changes allows for measures to be taken before acute loss of the access, which would necessarily lead to catheter implantation.

In the presence of any of these changes, the nursing team was advised to make contact with the nephrologist and the surgeon, so as to save the access before it is definitively lost.

Paid surgical services

It was proposed that all the units hire paid surgical services so that the rights and duties involved could be discussed between the parts.

After the implementation of the program the following objective results were observed:
  • Decrease in the use of the subclavian vein for insertion of short-term catheters, from 47.13% in September 1999 to 42.35% in September 2000.
  • In terms of paid surgical services: In September 1999 17 units employed paid surgical services; one year after the implementation of the program, all 23 units had hired paid services.
The most expressive results were expected for 5 years following the implementation of the program. An annual site visit was scheduled with new training sessions and verification of how the problems that had been previously identified had been solved.

For reasons beyond our control the program was interrupted and we were unable to collect long-term data.

DISCUSSION

The proposed program was based on the observation of each of the units under evaluation. For each of these units, the problems referring to the construction, maintenance and handling of vascular access were recorded and evaluated.

After one year of observation and an extensive review of the literature, a CQI program was proposed and implemented.

The review of the literature provided a strong basis for the conclusion of the project. The concept of sparing vessels was based on the ideal vascular access as described by Ryan & Dennis15 in 1990.

In 1997, Sands & Miranda10 reported that only 40% of terminal chronic renal patients had received some guidance concerning vascular access. In our project, we proposed more involvement on the part of physicians so as to guide patients and other health care professionals in charge of puncturing the vessels about the importance of avoiding the early deterioration of the superficial venous network.

The indication for early construction of the access was also discussed. According to Hakin,1 the relative risk for morbidity in patients in whom the access is constructed six months before the beginning of hemodialysis is half that of patients whose access is constructed one month before the start of the treatment.

The use of the subclavian vein for insertion of catheters is a great obstacle for maintaining vascular access, because after three weeks venous pressure may increase to 100 mmHg, without radiological signs; after five weeks, venous pressure may reach 120 mmHg with radiological evidence of stenosis.14 This fact would compromise the entire extremity in relation to the placement of a permanent access.

The role of the surgeon should not be restricted to the surgical act only. The involvement of surgeons must occur at the stages of creation, maintenance and handling of the access. Based on multivariate analysis, Hakin1 concluded that the surgeon was the most important factor associated with the loss of vascular access, in comparison to factors such as diabetes, age, and smoking, among others.

The multidisciplinary team approach was proposed based on the work published by Allon,16 in which the author proposes a full-time service for the construction of vascular access, with a dedicated coordinator, regular meetings to evaluate results, and participation of physicians specializing in angiology, radiology and ultrasonography, among others. The multidisciplinary team proposed for the Brazilian setting includes nurses, nephrologists and surgeons. The inclusion of angiology, radiology and ultrasonography specialists depends on the existence of these services at each unit.

The need to employ paid surgical services is supported by evidence observed during the site visits, since there was a major problem in terms of scheduling and connection between the clinical and surgical teams in the absence of a relationship involving paid services. This aspect has not been addressed in the literature.

CONCLUSIONS

The CQI program was created for implementation in hemodialysis units and long-term application. The initial proposal included yearly site visits and evaluation at all units to reinforce programmatic points and create the conditions for the continuous education of all professionals associated with vascular access.

The program was implemented and evaluated only once, after one year. The initial results were positive: the use of the subclavian vein decreased and paid surgical services were hired at all units. Possibly, this project could be the start of a research line, to be evaluated in the long-term.

ACKNOWLEDGEMENTS

The author thanks Renal Therapy Service - RTS, which made the program possible; Dr. Miguel Carlos Riella, for trusting the program and contributing to its creation; the 23 participating units and the physicians and nurses in charge, for making the program possible and for their invaluable contribution.

Participating Clinics:
Assistência Médica Nefrólogica de Guarulhos - São Paulo
Centro de Diálise e Transplante - Porto Alegre, state of Rio Grande do Sul
Centro Integrado de Nefrologia - Rio de Janeiro, state of Rio de Janeiro
Centro Nefrológico de Minas Gerais - Belo Horizonte, state of Minas Gerais
Clínica de Nefrologia Santa Teresa - Rio de Janeiro, state of Rio de Janeiro
Clínica Nefrológica de Minas Gerais - Belo Horizonte, state of Minas Gerais
Clínica N.S. Bonfim - Feira de Santana, state of Bahia
Clínica N. S. Bonfim - Salvador, state of Bahia
CLIRENAL - Caratinga, stage of Minas Gerais
Grupo de Assistência Médica Nefrológica - Rio de Janeiro, state of Rio de Janeiro
São Jorge Serviços Nefrológicos - São Paulo, state of São Paulo
Instituto de Hemodiálise de Sorocaba, state of São Paulo
Instituto do Rim - Fortaleza, state of Ceará
Nefromed - Ponta Grossa, state of Paraná
Néfron - Ribeirão Preto, state of São Paulo
Néfron - Contagem, state of Minas Gerais
Nephron Assistência Nefrológica - São Paulo, state of São Paulo
Núcleo de Nefrologia de Belo Horizonte, state of Minas Gerais
Clínica de Doenças Renais - Campos, state of Rio de Janeiro
Renalclin - Manhuaçu, state of Minas Gerais
Renalcor - Rio de Janeiro, state of Rio de Janeiro
Serviço de Nefrologia de Ribeirão Preto, state of São Paulo
Unidade Nefrologia e Transplante Renal - São Paulo, state of São Paulo

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J Vasc Br - Official Publication of the Brazilian Society of Angiology and Vascular Surgery