The purpose of this study is to evaluate the effect of pharmacogenetics (PGx) guided treatment when implemented into the pre-operative process for patients undergoing bowel surgery, major urologic procedure, or major ventral hernia repair and requiring post-operative acute pain management in an inpatient basis, as compared to a group of subjects with the same attributes without the guidance of PGx testing (historical control group). This study will also evaluate the frequency with which the standard analgesic care plan is adjusted by test results.

The incidence of opioid-related adverse drug events can reach as high as 50% in surgical patients and poor pain management is a significant risk factor for early readmission. In addition, the rate of non- response to certain analgesics is double in patients who are poor metabolizers as demonstrated by mutations in both CPY26D alleles. There is a growing body of literature that indicate that ineffective acute pain management contributes significantly to the risk of chronic pain syndromes. Genetics and drug interactions can alter both the pharmacokinetics and pharmacodynamics of a multitude of drug compounds and in turn influence both the safety and efficacy of selected therapeutic regimens.

Pharmacogenetic-guided therapy selection can enhance patient response by facilitating the selection of the most appropriate medication at the most effective dose in the shortest possible time.

In this prospective, observational, single-blind study, the investigators will evaluate the clinical impact of pharmacogenetics-guided treatment on patient well-being as determined by post-op pain assessments and the frequency of changes in analgesics predicted by testing results. Additionally, the impact of PGx-guided treatment on narcotic consumption, time to mobilization, number of adverse events, length of stay, and re-admission rates compared to historical data will be evaluated during the duration of the study.

Inclusion Criteria:

• Male or female subjects over the age of 18
• Presenting to the site for a prep-op visit prior to undergoing a major bowel surgery, major urologic procedure or major ventral hernia repair. The pre-op visit must occur at least 3 days prior to the surgical procedure.
• Willing and able to comply with study procedures
• Able to provide written informed consent

Exclusion Criteria:

• Unwilling or unable to provide written informed consent and to comply with study procedures;
• Unwilling or unable to provide buccal swab sample
• History of chronic renal dysfunction, Chronic Kidney Disease (Stage 4 or 5);
• New York Heart Classification >3
• Abnormal hepatic function within the last 2 years (INR >1.2 not attributable to anticoagulant medications, AST/aspartate aminotransferase or ALT/alanine aminotransferase >1.5x normal, or suspected cirrhosis);
• History of malabsorption (short gut syndrome);
• Gastric or small bowel surgery less than 3 months prior to study enrollment;

Patients presenting to the site for a prep-op visit prior to undergoing a major bowel surgery, major urologic procedure or major ventral hernia repair. The pre-op visit must occur at least 3 days prior to the surgical procedure.