The patient is draped and prepared for surgery.

This is relatively non-stimulating for the patient and the induction and volatile agents are both CVS and respiratory depressants. A drop in blood pressure and HR may be observed.

Knife to Skin (KTS) - the surgeon will normally alert the anaesthetist that surgery is about to commence.

It is vital for the anaesthetist to be vigilant at this point. If too lightly anaesthetized, the patient may respond with autonomic activity when the skin incision is made (increase in heart rate and blood pressure).

It may be necessary to adjust the anaesthetic depth by increasing the volatile agent or administering a small dose of opioid. If the patient is very light an extra dose of propofol can be useful.

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