The words tijera and tijeras can be used interchangeably in Spanish to refer to a single pair of scissors.
Both IV sedation (twilight) and general anesthesia are used commonly for cosmetic or plastic surgery. Regardless of technique, the patient's vital signs must be monitored, which include but not limited to heart rate, blood pressure, and breathing rate.
Indeed general anesthesia does have its downsides, such as the need for breathing assistance (ventilation), nausea-related side effects, and increased costs. There is an alternative to general anesthesia called twilight anesthesia.