Bortolotti became the first repeat winner of 2023 when he beat Abt Audi's Ricardo Feller in a race-long battle at the 4.3km circuit, taking the championship lead in the process.
However, his post-race celebrations were rather tame due to heat exhaustion on a hot day in eastern Germany, with the ambient temperature reaching 30C and temperatures inside his car peaking at 70C.
Images showed SSR Performance mechanics having to pour water and ice cubes over Bortolotti when he returned to the parc ferme. The Italian driver was also seen sipping a can of soft drinks in order to cool himself down after the race.
"I immediately radioed through to the guys: 'Hey, bring me something to drink right away. I want something cold, because I have to get out of the car as quickly as possible,'" Bortolotti told broadcaster ran.de.
"That's why I didn't enjoy the lap after crossing the finish line, which you normally enjoy because that's how you win a race."
Bortolotti also struggled with heat inside the car in Saturday's opening race, where he finished second to Emil Frey Ferrari driver Jack Aitken.
The Lamborghini Huracan is one of the few GT3 cars without air conditioning, and the main cooling system on the latest Evo version is also understood to be worse than the previous model.
"Especially when you roll back to the pits after the race, all the heat comes into the car," he explained. "At that moment it gets pretty hot in the cockpit, but I'm feeling better now.
"In the last laps, I was always asking, 'How many more laps can we do? Luckily everything is fine, but we have to work on the cooling somehow, because it's really hot in the car."
Source: Autosport