Table 1 Assessment of Leiden surgical space conditions (Leiden surgical rating scale) [10]

1

Extremely poor conditions

The surgeon is unable to work because of coughing or the inability to obtain a visible laparoscopic field because of inadequate muscle relaxation.

2

Poor conditions

There is a visible laparoscopic field, but the surgeon is severely hampered by inadequate muscle relaxation with continuous muscle contractions, movements or both with the hazard of tissue damage.

3

Acceptable conditions

There is a wide visible laparoscopic field but muscle contractions, movements or both occur regularly, causing some interference with the surgeon’s work.

4

Good conditions

There is a wide laparoscopic field with sporadic muscle contractions or movements, or both.

5

Optimal conditions

There is a wide visible laparoscopic working field without movement or contractions.