An HSS research team, led by Michael P. Ast, MD,  a hip and knee surgeon and chief innovation officer at HSS, designed a pilot study to gather data on the use of oral ketamine + aspirin as a post-operative pain management tool for total knee arthroplasty patients.

Dr. Ast and his team enrolled 22 men and women between the ages of 47 and 81 who were scheduled to have a total knee replacement procedure. The participants had no history of opioid use. Each person received an oral dose of aspirin and ketamine four times a day until discharge (up to 72 hours).

“This formulation of ketamine allows for oral use and is also manufactured in a way that it cannot be abused by melting or crushing. It allows the patient to let the pill’s coating dissolve for about 20 seconds and then swallow, which primes the system to absorb the drug. That mechanism of action seems to change the bioavailability of ketamine, which was always a huge challenge,” explained Dr. Ast. 

“The combination of oral ketamine and aspirin had previously been studied in a Brooklyn, NY emergency room where that particular research team compared opioids to an oral ketamine/aspirin combination for pain relief. They reported excellent results so that made me think that this might work for TKR [total knee replacement] as well,” said Dr. Ast. 

“Because of this formulation’s unique bioavailability and the low dose, we found the use during this study to be extremely safe. Anecdotally, patients obtained excellent pain relief. The majority of patients—18 of the 22—reported no side effects from the treatment. Two patients reported feelings of dizziness. Two others withdrew from the study early because they felt they needed more pain relief,” explained Dr. Ast. 

Eventually, rather than sending patients home with 20 or more opioid pills, Dr. Ast wants to be able to release patients with only a few—safe and effective—pills.

Read the full article at ryortho.com.