Calculating anaesthetic - will they weigh me on the day?

So I'm getting keyhole surgery in a couple of weeks but by then it will have been 6 weeks since my pre-operative assessment. During that I was weighed (fully dressed and after having eaten breakfast) and measured and asked about my medical history. Since then I've lost about 3kg through healthy eating and regular exercise.

I'm presuming they weigh and measure you so that they can calculate how much anaesthetic they'll need to knock you out but will this weight difference have any effect? Will they weigh me on the day of surgery or should I mention it to them? Advice would be appreciated

So I'm getting keyhole surgery in a couple of weeks but by then it will have been 6 weeks since my pre-operative assessment. During that I was weighed (fully dressed and after having eaten breakfast) and measured and asked about my medical history. Since then I've lost about 3kg through healthy eating and regular exercise.

I'm presuming they weigh and measure you so that they can calculate how much anaesthetic they'll need to knock you out but will this weight difference have any effect? Will they weigh me on the day of surgery or should I mention it to them? Advice would be appreciated