Kante has started just 20 of Chelsea's 37 matches in the Premier League this term, missing out on 12 games entirely.
The 31-year-old played 71 minutes as Leicester City held Chelsea to a 1-1 draw at Stamford Bridge on Thursday.
Chelsea are well set to claim third place in the league and Tuchel's is surprised about the position given the number of games Kante has missed.
Tuchel has likened Kante's importance to Chelsea to the impact some of the world's best players have on their teams and wants a quick fix to the Frenchman's injury troubles.
"I think he is our key, key, key player, but key, key, key players need to be on the pitch. He plays only 40 per cent of the games, so then it is maybe a miracle that we arrive in third place," Tuchel said.
"He is our Mo Salah, he is our [Virgil] van Dijk, he is our [Kevin] De Bruyne. He is simply that player, he is our Neymar and Kylian Mbappe.
"He is that guy who makes the difference and if you only have him for 40 per cent then it is a huge problem. Given that percentage, it is maybe a miracle that he produces results.
"It puts everything into perspective as I saw Liverpool without Van Dijk last season and they struggled heavily. You see the difference. N'Golo is our key player and we need him on the pitch.
"It's hard to live with. It's important for him to be there and to have the rhythm. I think he played okay but he can play so much better. But when was the last game he started? It was weeks ago. So he constantly starts getting rhythm, but once he has that, there comes a little injury and he's out again.
"Last year, in the last five matches of the Champions League, he got the [man of the match] trophy. This guy who gets man of the match in every Champions League game, he is only here for 40-something per cent of the matches. This is huge for us."
