Blue Light Therapy for Liver Surgery

Study Overview
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Brief Summary
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The investigators hypothesize that subjects undergoing liver resection and who are exposed preoperatively to high illuminance blue spectrum light will exhibit reduced organ injury, specifically liver dysfunction, than subjects exposed to standard ambient white fluorescent light.

Official Title
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Blue Light Therapy for Liver Surgery

Conditions
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Acute Kidney Injury, Liver Injury, Inflammation

Intervention / Treatment
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* Other: Blue light


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age greater than 17 years undergoing right or left hepatic lobectomy Exclusion Criteria: presence of acute traumatic brain injury blindness immunosuppression or immunocompromised condition

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Blue light<br>Subjects will be exposed to 24 hours of bright (1700 lux) blue (peak 442 nm) spectrum light the day prior to operative intervention and for the 24 hours after the operative intervention. | Other: Blue light<br>* Illumination: High illumination lighting will be instituted with a Day*Light Classic Light (Uplift Technologies, Dartmouth, NS) Blue wavelength: Each subject will be fitted with blue filtered goggles (Lee Filters, Burbank, CA). These goggles ensure the transmission of a bright (1700 lux) blue (peak 442 nm) spectrum light when the subject is within 12 inches. Photoperiod: A 24-hour photoperiod will be used that commences at 0800 the morning prior to surgery and continues for 24 hours. To account for potential variability in the exposure of interest, each subject will complete a diary to catalogue duration and distance of light exposure. Postoperatively the same photoperiod will be instituted and continued for one 24 hour period.<br>|
| No Intervention: Ambient light<br>Subjects will be exposed preoperatively to the lighting conditions of their living environment and postoperatively to the standard, white fluorescent lighting environment of the hospital. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from baseline creatinine concentration at 24 hours after surgery | a serum marker of acute kidney injury | preoperatively and 24 hours after surgery | 
| Change from baseline alanine aminotransferase (ALT) concentration at 24 hours after surgery | a serum marker of acute liver injury | preoperatively and 24 hours after surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in serum cytokine concentrations at 24 hours after surgery | serum will be analyzed for cytokines and inflammatory mediators | 24 hours after surgery | 
| Ventilator-free days |  | for the duration of postoperative inpatient hospital stay up to 28 days | 
| ICU length of stay |  | for the duration of postoperative inpatient hospital stay up to 28 days | 
| renal replacement therapy |  | for the duration of postoperative inpatient hospital stay up to 28 days | 
| Change in serum cytokine concentrations at 1 hour after surgery | serum will be analyzed for cytokines and inflammatory mediators | 1 hours after surgery |