Dasilva is out of contract this summer and has played just five times this season. Last weekend, he suffered serious ligament damage in an injury that means he will likely not play again this season.
The 25-year-old missed 12 months between February 2021 and February 2022 with a hip injury, and only returned last month from a hamstring injury he sustained in August.
The midfielder had endured an injury-plagued Brentford career since joining the Bees from Arsenal in August 2018, and his future with the club is in doubt.
“I think, as any business, it is the on- and offboarding of players that we need to look after,” Frank said.
“He needs to go through the surgery first so we get a clear picture of that. But, of course, we would like to look after players and do what we can to help them in the future. We will take a decision on that after the surgery.
“He’s got a very positive mindset which I think is important. I have no doubt in the last days, but also will have in the next months, some dark hours, which is natural.
“But, overall, he is positive, with a good support network. We will do what we can to support him in that process.”
Meanwhile, full-back Aaron Hickey is currently out with a long-term hamstring injury, and Frank has revealed the 21-year-old’s return has been delayed.
“Unfortunately, he had a minor setback,” Frank said. “I don’t know a return date.”
Asked whether he will return this season or in time to represent Scotland at Euro 2024, Frank said: “That I don’t know. I hope, but sometimes when players have been out for a while I like to see them back on the grass before I comment an estimated guess on what is possible or not. He had an operation to his hamstring.”