Acute Kidney Injury, Inflammation
Conditions
Brief summary
The goal of this study is to determine whether or not exposure to blue spectrum light reduces acute kidney injury and systemic inflammation in subjects undergoing cardiopulmonary bypass. Subjects scheduled to undergo cardiopulmonary bypass surgery will be exposed to either bright (1000 lux) blue spectrum (480nm) light or to ambient, white fluorescent light for a 24 hour photoperiod the day prior to surgery and for a 24 hour photoperiod in the immediate postoperative period.
Detailed description
Light modifies the biology and physiology of mammals, including humans. The cellular biology of both the immune system, as well as, the cells comprising tissues and organs (e.g., kidney, liver) are under the regulation of light and exhibit circadian rhythms. Studies show that the severity of organ injury varies with the time of the day, the duration of the day, and the season. This variation is due to the biology of circadian rhythms, and light is the principle environmental cue entraining circadian biology. More recent data suggest that modulating the spectrum of light to which an organism is exposed may therapeutically modulate the cellular response to stress or injury. Specifically, exposure to a short (24 hour) photoperiod of high illuminance, blue spectrum light attenuated liver and kidney injury when animals were subjected to ischemia/reperfusion (I/R), a model in which the blood flow to an organ is temporarily reduced and then restored. A predominant cause of organ injury in this model is the misdirected and exacerbated inflammation of a type of immune cell called the neutrophil. However, blue light inhibited neutrophil infiltration into the ischemic kidney and liver, and thereby reduced inflammation and neutrophil-mediated organ injury. Cardiopulmonary bypass (CPB) surgery is an operation characterized by excessive inflammation and a high risk of organ injury, particularly acute kidney injury (AKI). Thus, we hypothesize that exposure to blue light, by comparison to standard environmental, white fluorescent light, will reduce inflammation, organ injury and improve the outcome of patients undergoing CPB.
Interventions
OTHERBlue light
Exposure to high illuminance (1000 lux), blue spectrum (480 nm) light for a 24-hour photoperiod immediately before surgery and a 24-hour photoperiod immediately after surgery
Sponsors
University of Pittsburgh
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* age greater than or equal to 18 years * undergoing cardiopulmonary bypass surgery
Exclusion criteria
* Blindness * Immunocompromised or immunosuppressed state * Anticipated survival \< 24 hours
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in creatinine concentration | Change in serum creatinine concentration at 24 hours after surgery compared to preoperative baseline creatinine concentration | The change in serum creatinine after intervention compared to baseline. |
| Change in blood urea nitrogen (BUN) concentration | Change in serum BUN concentration at 24 hours after surgery compared to preoperative baseline BUN concentration | The change in serum BUN after intervention compared to baseline. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| duration of ICU stay | within 28 days after surgery | ICU length of stay 28 days after surgery and intervention |
| duration of hospital stay | within 28 days after surgery | Hospital length of stay 28 days after surgery and intervention |
| Inflammation | Change in serum cytokine concentrations comparing serum concentrations at 24 hours after surgery to serum concentrations immediately (with 1 hour) after surgery | The change in serum concentration of inflammatory mediators after intervention compared to baseline. |
| Duration of renal replacement therapy | within 28 days after surgery | Days of dialysis within the first 28 days after surgery and intervention |
| Ventilator-free days | within 28 days after surgery | Cumulative days without mechanical ventilation 28 days after surgery and intervention |
| all cause mortality | within 28 days after surgery | Death 28 days after surgery and intervention |
Countries
United States
Outcome results
None listed