effect of combinational changes of catheter size and its negative suction pressure on hemodynamic parameters of mechanical ventilation patients

 aims: endotracheal suctioning is the most effective way to clear discharge and maintain open airway. this is usually done by nurses. this study aimed to determine the effect of combinational changes of catheter size and its related suction negative pressure on hemodynamic parameters of patients undergoing mechanical ventilation.materials & methods: in this clinical trial study, thirty-five patients undergoing ventilators were eligible for inclusion were selected by available sampling method. endotracheal suctioning was performed for each patient 4 times with at least 2 hours interval by catheter 10 and 12 and negative pressures of 100 and 150 were used. hemodynamic parameters of all patients were recorded immediately before, immediately after, 10 and 20 minutes after each intervention. the data were then analyzed using spss 21 and anova with repeated measures.findings: suctioning with catheters 10 and 12 at pressures of 100 and 150 increased the hemodynamic parameters immediately after endotracheal suction. these increases was significant in systolic blood pressure (p=0.004) and mean arterial blood pressure (p=0.01). this test showed a statistically significant difference between intervention and intra-intervention in mean arterial oxygen saturation at post-suction time (p=0.001).conclusion: although the catheter 12 and pressure 100 and 150 indicated a greater increase in hemodynamic parameters at the time immediately after endotracheal suctioning, the changes are minor and within the normal range and decreased 10 and 20 minutes after the procedure and approached pre-suction time.