After surgery, most patients are eager to recover and get back to their normal routine. But, for nearly one-third of patients, anesthesia drugs make them sick to their stomach and they start vomiting. This is what physicians call post-operative nausea and vomiting. It can be an uncomfortable side effect from anesthesia or pain medications.
Some patients are at higher risk: women, nonsmokers, those with a history of motion sickness or those undergoing ear, eye or bariatric surgery. Medications are given to prevent nausea or treat it if it occurs after surgery – but not all patients get relief.
Researchers in the Mayo Clinic Center for Individualized Medicine are exploring whether a personalized approach to treat nausea after surgery will help improve recovery for all patients. They are studying the use of pharmacogenomics, the practice of understanding how each person’s genes affect how their body processes medications. This could help physicians identify better drugs to prevent nausea and vomiting.
“Anesthesiologists are perioperative physicians whose job is to take care of the patient throughout the perioperative period, not just provide medications to put the patient to ‘sleep’ during surgery. Pharmacogenomics may help improve all aspects of care before, during and after surgery. As a first step, we are focusing on how pharmacogenomics may help treat post-operative nausea and vomiting. This condition is a common complaint for patients. It can not only affect how they feel immediately after surgery, but could interfere with their recovery by causing damage to the surgical area if not properly treated,” says Timothy Curry, M.D., Ph.D., a Mayo Clinic anesthesiologist and director, Mayo Clinic Center for Individualized Medicine Education Program.
A closer look at patients who undergo bariatric surgery
Since patients who have bariatric surgery are at high risk of having post-operative nausea and vomiting, Yvette Martin, M.D., Ph.D. and her research team will explore how pharmacogenomics could help reduce or eliminate nausea for these patients.
“We are planning an innovative research effort that will use genetic information prior to bariatric surgery to guide treatment of post-operative nausea and vomiting. Patients will undergo genetic testing prior to surgery, and based on their test results, physicians will select an appropriate therapy to control nausea. In addition, we’ll be asking physicians to provide feedback on the benefit of using pharmacogenomics to guide patient care, with the hope of identifying any barriers to using this promising tool for future studies,” says Dr. Martin, a Mayo Clinic anesthesiologist and principal investigator for the initial research studies on post-operative nausea and vomiting.
The role of genetics
As part of this research effort, Mayo investigators are examining a gene that has been shown to affect how the body processes common medications. Studies show that the CYP2D6 gene affects how patients process ondansetron, a common medication used to prevent nausea and vomiting after surgery. That finding could guide physicians to other medications which are more compatible with a patient’s genetic blueprint.
“Some patients have a genetic variation that causes them to be ‘rapid metabolizers’ of ondansetron, meaning they process the medication very quickly. We believe the drug may not control nausea for these patients because they process it so fast. So these patients may benefit from an alternative treatment,” explains Dr. Martin. “On the other hand, we think that those patients with a CYP2D6 variation that causes them to be ‘poor or slow metabolizers’ will get better relief from nausea with ondansetron because the drug stays in their system longer.”
Researchers found early evidence of these differences after examining the genetic and surgical data of the first 1,000 participants in the RIGHT 10K study. The RIGHT Protocol (short for the Right Drug, Right Dose, Right Time: Using Genomic Data to Individualize Treatment) has enrolled 10,0000 participants whose genetic test results will be added proactively to their Mayo Clinic electronic health record for future use. The aim of the study is to see if doing so improves long-term outcomes for both the patient and the health care delivery system at large.
"Our results could help us individualize therapy for post-operative nausea and vomiting and identify alternative therapies for those who do not respond to ondansetron,” – Yvette Martin, M.D., Ph.D.
“To confirm our initial results, we’ll conduct a larger scale review by examining the genetic and surgical data from all 10,000 RIGHT study participants. Our results could help us individualize therapy for post-operative nausea and vomiting and identify alternative therapies for those who do not respond to ondansetron,” says Dr. Martin.
As part of this research effort, Dr. Martin is using information from OR Datamart, a unique database developed by Mayo anesthesiologist Daryl Kor, M.D., and his colleagues, that brings together clinical data for each patient from the Mayo Clinic surgical electronic health record system.
Join the conversation
See highlights from our recent Individualizing Medicine Conference 2017: Advancing Care Through Genomics:
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Tags: #bariatric surgery, #CIMCon17, #Dr. Yvette Martin, #individualized therapy, #Individualizing Medicine 2017, #ondansetron, #post-operative nausea and vomiting, center for individualized medicine, DNA Sequencing, Dr. Timothy Curry, Genetic Testing, mayo clinic, medical research, pharmacogenomics, Precision Medicine