Introduction: The concept of systemic inflammatory response syndrome (SIRS) was proposed by the American College of Chest Physicians and the Society of Critical Care Medicine in 1991.

This condition, which can complicate the course of surgery and cause postoperative complications, was studied in thoracic and gastrointestinal surgery; however, there are very few studies of SIRS in orthognathic surgery (OS).

Objective: See if SIRS is present during the OS intraoperative.

Patients and methods: Eleven patients aged 16–42 years with dentoskeletal dismorfosis underwent OS during January and February of 2008.

We recorded at the beginning and end of the procedure:

• 1.

  Body temperature = esophageal thermometer,

• 2.

  PaCO ₂ ,

• 3.

  white blood cell count,

• 4.

  heart rate.

SIRS is defined when two or more of the following variables are present:

• 1.

  Body temperature greater than 38 °C or below 36 °C.

• 2.

  Heart rate greater than 90 beats per minute.

• 3.

  Respiratory rate greater than 20 breaths per minute or PaCO ₂ levels below 32 mm Hg.

• 4.

  Abnormal white cell count (>12,000/mL or <4000/mL or >10% bands).

Results: Two patients treated had at least two signs of SIRS during surgery.

The duration of surgery could be associated with a greater predisposition to SIRS.

Conclusions: More research should be carried out, increasing number of patients and assessing their postoperative evolution. However, these results suggest the importance of careful management and constant monitoring to prevent complications.

Conflict of interest: None declared.