It has been shown that oral hygiene reduces the incidence of ventilator-associated pneumonia (VAP). The nasopharynx is considered to be an important source of contaminated micro aspiration to the lung however, the effect of nasopharyngeal decontamination on VAP has not been yet investigated. The investigators hypothesized that decontamination of oral and nasopharyngeal cavities with combined Povidone Iodine and glycyrrhizin would remarkably reduce the incidence of VAP.

Infections that occur more than 48 hours after intubation are known as ventilator-associated pneumonia (VAP) and ventilator-associated tracheobronchitis (VAT). The incidence of VAP in mechanically ventilated patients ranges from 8 to 48% with a mortality rate of 24%-76%.

These infections are a serious problem that Increases the need for prolonged hospitalization, antimicrobial therapy, and rising healthcare expenses. As a result, preventing VAP and VAT is critical to improving the quality of life by reducing complications in mechanically ventilated patients.

Intubation is a mechanical procedure that Breaks the natural barrier, allowing bacteria to colonize. Microorganisms enter the lungs through the lower respiratory tract from the oropharynx, the endotracheal tube cuff leaks, or the biofilm in the endotracheal tube. The microbial flora in the oral cavities of hospitalized patients, particularly those mechanically ventilated, gradually changes; gram-positive bacteria of low virulence predominate at admission (Streptococcus spp., Actinomyces spp.) are gradually replaced by more virulent gram-negative, potentially pathogenic microbial flora. This change happens on mucosal surfaces as well as in dental plaque, which in the physiological state are populated by 200-350 different bacterial species. The nasal-oropharyngeal axis involves nasal secretions swept to the oropharynx by mucociliary clearance followed by the aspiration of infected fluid into the lower airway. Nasal-oropharyngeal axis with subsequent seeding of the lungs leads to respiratory disease. The investigators hypothesized that micro aspirates from the nasopharynx and oropharynx are substantially contributing to the development of both VAT and VAP and the decontamination of the nasal and oral cavity would greatly help in the reduction of VAP and VAT. The purpose of this study is to compare the effect of nasal and Oro-pharyngeal use of a combination of Povidone Iodine (PVI) and Glycyrrhizin (GA) [treatment group] for oral and nasal decontamination on preventing VAP and VAT with the placebo group. Another objective is to compare the effect of treatment used for oral care on oral health and the prevention of microbial colonization in the mouth with the placebo group.

Inclusion Criteria:

• on mechanical ventilation less than 24 h after admission and expected to continue mechanical ventilation for more than 72h.

Exclusion Criteria:

• Exclusion criteria include immunosuppression, aspiration pneumonia, all types of pneumonia, sepsis and septic shock, tracheostomy, and pregnancy.

All of the individual participant data collected during the trial, after deidentification.

Beginning 9 months and ending 36 months following article publication.

access criteria will be open for researchers, all data will be released except for personal identification for patients. To request data please contact the principal investigator e-mail. hazelsersy@hotmail.com

Only the pharmacist is aware of the randomization and preparing the study drugs. The pharmacist will encode the medication bottles and keep the code key confidential until the completion of follow-up of the last patient.