The Quest

Dr. Charmaine Lok’s research programs at the Toronto General Hospital focus on improving hemodialysis vascular access outcomes, improving neuromuscular function and mobility in CKD, and reducing cardiovascular events and mortality in CKD/ESRD. Many Kidney CARE members are directly involved, as students and/or volunteers, in several of these programs of research. A selection of these is presented here. Please feel free to contact us if you have any questions.

Dr. Lok’s Bibliography

Research Articles by Daisy Kosa

Dr. Lok’s Faculty Profile

Dr. Lok’s Research Highlights

Dr. Lok’s Breakthrough Technology

Prevention of Heart Attacks and other Serious Cardiovascular Events in Hemodialysis Patients

Protection against Incidences of Serious Cardiovascular Events Study (PISCES)*

Worldwide, over 5 million people with kidney failure require dialysis. Cardiovascular (CV), (heart and blood vessel) related events are the main causes of illness and death. However, there are no consistently proven medical therapies to reduce serious CV events. Fish oil may reduce risk factors that cause heart and blood circulation problems and improve health outcomes.

Dr. Lok and her research team are studying the effect of fish oil in reducing CV events in dialysis patients. In her clinical trial, over 1100 adult men and women on dialysis from different parts of the world have been enrolled. New knowledge gained from the results of this study could impact the care given to dialysis patients immediately. If fish oil is found to reduce serious CV events it will significantly improve patient health and may reduce CV-event-related deaths.

This international study is led by Dr. Charmaine Lok through the Toronto General Research Institute in Toronto, Canada. Dr. Kevan Polkinghorne is the lead investigator in Australia.

More information about the study can be found by clicking the button below.

STATUS: Ongoing

Maintenance of Hemodialysis Lifelines -- Vascular Access

My Vascular Access Mobile App – Updated!

Individuals with kidney failure who need hemodialysis need a “vascular access” to connect the patient’s blood circulation to the hemodialysis machine, so the patient’s blood can be cleaned. There are 3 main types of vascular access: arteriovenous fistula (fistula), arteriovenous graft (graft) and central venous catheter (catheter). The vascular access is known as the patient’s “lifeline” due to its importance, but each type of vascular access can encounter problems and are a focus of Dr. Lok’s research program.

A Mobile App to Help Clinicians Help Patients: My Vascular Access Mobile App – Updated!

Clinicians are guided by clinical practice guidelines for the management of many medical conditions. Guidelines often depend on expert opinion when rigorous evidence is lacking to provide strong guideline recommendations. Rightly so, expert opinion and evidence evolves with new technology, knowledge or data from well conducted studies.

Although clinical practice guidelines for the creation and maintenance of vascular access for hemodialysis exist, they offer general recommendations that are often not actionable on an individual patient level and the most appropriate type of hemodialysis vascular access for individual patients remains uncertain. In a previous study (here), using the RAND Appropriateness Method (RAM), a unique consensus process that combines the best available literature and expert opinion, a group of nephrologists, vascular surgeons, and transplant surgeons determined that vascular access selection should be dictated by patient-specific characteristics, including vascular anatomy, age, and functional status, rather than by a universal mantra such as “Fistula First”. The group also developed an algorithm and a mobile app (My Vascular Access mobile app) which was launched on the Apple and Android App Stores. Use the download links to access the free app. A web-based version of My Vascular Access can also be found here.

Since the original publication, newer technologies (e.g. early stick grafts, EndoAVF, HeRO graft and Humacyte AV access) which were not considered in the original study have evolved. As such, the RAM study and the My Vascular Access mobile app will be updated under the leadership of Kidney Care Network International’s Drs. Lok and Kosa, and the original lead investigator, Dr. David Cull. To date over 8,000 publications have already been reviewed to devlop this update.

STATUS: Ongoing

Perspectives of Hemodialysis Patients on Vascular Access

The Development of the Short Form- Vascular Access Questionnaire (SF-VAQ)

Patients receiving life-sustaining hemodialysis depend on a “vascular access” that connects their blood circulation to the hemodialysis machine, so that their blood can be cleaned. There are several forms of vascular access; and while the vascular access is known as the patient “lifeline”,  they each have their problems.

We developed a patient centred survey to measure hemodialysis patients’ satisfaction with their hemodialysis vascular access. The secondary objective was to evaluate the measurement tool’s psychometric properties to assess patient satisfaction with their vascular access (ie the “validity” of the tool).

We generated a comprehensive list of survey items related to patients’ views and satisfaction with their vascular access and administered it to participating in-center hemodialysis patients over 4 months. Following a factor analysis, the items were reduced and rescaled to generate the final short-form vascular access questionnaire (SF-VAQ). The SF-VAQ was then validated on a new cohort of hemodialysis patients.

We have successfully developed the SF-VAQ – a short, simple to administer vascular access-specific questionnaire with robust psychometric properties that can be used to obtain the patient’s views on their vascular access. Based on the newly developed SF-VAQ scores, patients were the most satisfied with a type of “native access” called fistulas.

The SF-VAQ has been translated into several languages and is being used around the world.

STATUS: Complete

Understanding how patients view the cosmetic appearance of their vascular access and how it may impact the patient.

Development of the AVACS Scale

Cosmetic appearance is a key concern for patients on hemodialysis with a fistula or graft, two types of vascular access. The fistula or graft  is often referred to as  “arteriovenous access” in medical terms. A significant number of patients with kidney failure who need hemodialysis deny creation and use of a fistula or graft (arteriovenous access) due to concerns of the disfigurement and stigma of having a visible reminder of their health condition.

At present there are no objective measures of vascular access appearance which could potentially help in choosing the right type of vascular access for the patient. This vascular access is so important because a patient cannot have life-sustaining hemodialysis without it.  Dr. Lok and others wanted to understand patient’s views so they could be addressed in future work on vascular access, to help bridge patients’ needs for vascular access and patient expressed concerns about living with vascular access.

Dr. Lok and team created a scale to measure the cosmetic appearance of AV accesses. This scale is called “AVACS”. This scale consists of two subscales: a) patient subscale, where the patients subjectively assess their accesses and categorize/score the questionnaire, b) clinician subscale, where the health care professionals involved in the patients’ care score the AV accesses.

To further test the validity of the cosmetic appearance measurement scale, a study has been undertaken to assess the feasibility of using it in the real-world situations. The study also looks at comparing the scores between the different health care professionals to test the reliability of the scale. An expert panel will finally evaluate and analyze the outcomes of these assessments to establish validity of the scale.

The AVACS has been translated into several languages and is being validated in different parts of the world

STATUS: Ongoing

Kidney CARE Network International

Hemodialysis Infection Prevention with Polysporin Ointment in Satellite Centres

HIPPO Shower Technique

Individuals with kidney failure who depend on hemodialysis (dialysis) are often advised not to shower if they have a central venous catheter (catheter), because of the potential increased risk of catheter-related infection (infection) when showering with a catheter. However, not being able to shower may impact a patient’s quality of life.

We developed a shower technique catheter protocol for dialysis patients with healed catheter exit sites, designed to permit showering but not increase infection risk. We want to test whether this shower technique protocol would allow patients to shower safely. However, before conducting a large “definitive” study, we need to see if such a study is feasible ie whether patients would want to participate and test out the shower technique protocol.

We tested the feasibility of conducting a rigorous study to compare the rate of infection in adult satellite dialysis patients using the shower technique protocol versus standard catheter care alone with 6 month follow up. Other important outcomes, such as patient quality of life are measured in Kidney CARE’s members related studies.

STATUS: Complete