<qa>  How many patients mechanically ventilated in intensive care unit are included in this study?The aim of this study is to compare the effects propofol and dexmedetomidine on pulmonary mechanics. Sixty patients mechanically ventilated in intensive care unit are included in this study. Patients are divided into two random groups, Group P propofol and Group D dexmedetomidine. Propofol infusion 0.5-2 mgkgh is given to Group P patients and dexmedetomidine infusion 0.2-0.7 mcgkgh is given to Group D patients for sedation. Initial blood gas analysis, airway resistance cmH2OLsec, positive end-expiratory pressure PEEP, cmH20, frequency breathmin, tidal volume mLmin, minute volume mL, peak airway pressure cmH20, compliance mLcmH20, endtidal CO2 mmHg, SvO2 values are recorded. This parameters are evaluated with Drager Evita 4 ventilator and recorded on 5th,15th,30th,45th ve 60th minutes . Sedation is observed using Riker and Ramsey Sedation-Agitation Scale. Compliance of patients to mechanical ventilation is observed and recorded. 