The goal of this prospective observational study is to define a risk profile for cardiovascular surgery associated acute kidney injury (AKI), using clinical patient characteristics, operation parameters as well as blood and urine laboratory values. The main question it aims to answer is: • Does a combination of the factors mentioned above better predict patient outcome than classical factors used to date in clinical practice? Participants of this study are adults aged 18 and above who are scheduled for elective heart or main artery surgery, and who have given written informed consent.
The difficulty of precisely predicting AKI following major surgery is a clinical challenge and unmet need as treatment should be introduced within 24-48 hours. In addition there is no available treatment to date apart from supportive therapy such as renal replacement therapy. Therefore, early identification of patient-specific biomarkers and other clinical predictors could help to better understand the association with AKI and other patient outcomes. In addition to the "classical" risk factors (age, diabetes, pre-existing CKD), frailty might represent another important variable, as shown in previous observational studies. Importantly frailty is not unique to age, although it occurs in approximately 25% of those over 65 and affects more than half of the population aged 85 and older, as it has been shown to be highly prevalent in hospitalized patients and/or patients with CKD. Furthermore, in preclinical studies the serum protein Fetuin-A was identified as potential biomarker for vascular surgery associated AKI. PEAK is a single center, prospective observational study involving several clinics at the University Hospital Bern. Besides from demographic data and perioperative parameters, blood and urine are collected with high granularity during and immediately after surgery (15min after the first cut, start and end of cardiopulmonary bypass (CBP) or aortic clamping (X-clamp), 4 hours after surgery) and at day 1, 2, 3, and 7 (or discharge) post-surgery. In addition renal function will be assessed at day 90. Furthermore, study participants will answer the Edmonton frailty questionnaire at baseline and at day 90.
Study Type
OBSERVATIONAL
Enrollment
100
University Hospital Bern (Inselspital)
Bern, Switzerland
RECRUITINGChange from baseline of serum Fetuin-A values
Measurement of serum Fetuin-A at baseline and at the various sampling time-points mentioned above.
Time frame: Baseline to day 90
BMI
Body mass index of participants in (kg/m2), integer: min 15 (extreme underweight), max 45 (extreme overweight)
Time frame: Baseline and day 90
eGFR
estimated glomerular filtration rate in (ml/min)
Time frame: Baseline and day 90
Proteinuria
Albumin in urine normalized to creatinine in categorized into 3 groups: 1. \<30 mg/d 2. 30-300 mg/d 3. \>300 mg/d
Time frame: Baseline and day 90
ASA score
American Society of Anesthesiology classification of physical status (1-6) 1. \- Normal health 2. \- Mild systemic disease 3. \- Severe systemic disease 4. \- Severe systemic disease that is constant threat to life 5. \- Moribund, not expected to survive 24h with or without operation 6. \- Declared brain-dead
Time frame: Baseline
Euroscore II
Euroscore II, predicted mortality in (%)
Time frame: Baseline
STS score (only for cardiac surgery)
Society of Thoracic Surgeons Score in (%), higher values predict higher risk
Time frame: Baseline
Duration of ECC (only for cardiac surgery)
Time on extracorporeal circuit in (min)
Time frame: Peri-operative
Duration of X-clamp (only for aortic surgery)
Time of X-clamping in (min)
Time frame: Peri-operative
Lowest body temperature
Lowest body temperature recorded during surgery in (°C)
Time frame: Peri-operative
SAPS II score
Simplified Acute Physiology Score (SAPS) II°C), in-hospital mortality at ICU admission, integer min 1, max 200, higher values predict higher mortality
Time frame: After Operation to day 7
Urine output
Daily urine volume in (ml)
Time frame: After Operation to day 7
Assessment of AKI incidence and severity at day 7 in association with change in serum Fetuin-A levels over time
AKI will be assessed as a binary outcome (presence/absence) Biomarkers for AKI severity include levels of direct Fetuin-A targets, kidney function parameters, predictors of AKI or CKD (NGAL, suPAR, Nephrocheck®, or YKL-40), hemolysis (hemoglobin, transferrin), inflammatory mediators (cytokines, chemokines or growth factors), and exploratory assessments (proteomics, metabolomics).
Time frame: Baseline to day 7
Assessment of AKI to CKD progression at day 90 in association with change in serum Fetuin-A levels over time
CKD will be evaluated as a binary outcome (presence/absence) based on renal functional parameters.
Time frame: Baseline to day 90
Assessment of the patient-reported outcome measure (PROM) frailty in association with progression to CKD and worse clinical outcome
Frailty in terms of patient-related outcome will be reported as a paired difference of mean frailty score (Edmonton Frail Scale) between baseline and 90-days visit. The scale ranges from 0 (not frail) to 17 (severe frailty).
Time frame: Baseline and day 90
Grip strength
Grip strength of dominant hand in kg
Time frame: Baseline and day 90
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.