This study is semi experimental clinical trial. In this trail, eighty ICU patients that they have 18-60 Y/O and low GCSS (Glascow Coma Scale Score) because of head injury are enrolled. The level of consciousness of these patients, according to clinical information, diagnostic CT scan and Counseling with Neurologist, will not rise up to 21 days. Therefore, they are undergoing tracheostomy surgery at the first 3 days after ICU admission. Then the eligible patients randomly allocated into one of two groups. In the intervention group, the absorbable foams are used for dressing of theracheostomy site for 7 days and in the control group the normal gas are used for dressing of theracheostomy site for 7 days. These absorbable dressing foams or normal gas are put on in the theracheostomy site immediately after theracheostomy surgery. Then the culture samples from the tracheostomy site are prepared in 24, 72, 168 hours after tracheostomy surgery and sent to the laboratory as blind. These Patients should receive the same antibiotics in ICU. The patients with Diabetes, Pneumonia, Renal failure, Hepatic failure, Chronic cardiopulmonary disorders, history of antibiotic therapy from last, clear infection signs in anterior neck, anterior neck burning and foam sensitivity are excluded from the study.