[Endotracheal aspiration: respirator vs. manual resuscitation as method for hyperoxygenation and hyperinflation]. / Aspiración endotraqueal: respirador versus resucitador manual como método de hiperoxigenación e hiperinsuflación.

Endotracheal aspiration protocols (EAT) include hyperoxygenation and hyperinflation to minimize the negative effects of the technique. No conclusive studies have determined the most effective hyperoxygenation and hyperinflation method. This study had two aims: to compare the effects on patient oxygenation and hemodynamics during endotracheal aspiration of secretions using, respectively, a respirator or manual resuscitator as the hyperoxygenation and hyperinflation method. Tidal volume (TV) and FIO2 with the manual resuscitator were quantified. The study was based on 172 aspiration sessions carried out under artificial ventilation in the immediate postoperative period of 26 patients who had undergone cardiac surgery without lung damage. Hyperinflation and hyperoxygenation before, during and after aspiration were carried out with and artificial ventilator in group I and with a manual resuscitator in group II. In all aspiration interventions, an analysis was made of hemodynamic parameters (MAP, MPAP, HR, CO and arrhythmias), ventilation and oxygenation parameters (HR, FIO2, SpO2, and SvO2), and the influence of the method on the appearance of atelectasis. Both methods produced small increases in all hemodynamic parameters, and significant differences in HR (p < 0.001) and MPAP (p < 0.002), although no clinical repercussions were observed. No severe arrhythmias were observed. No statistically significant differences between the two methods were found in the evolution of SpO2 and SvO2, which remained above baseline levels throughout both procedures. Analysis of the effectiveness of the manual resuscitator (the second aim) under the conditions established yielded a mean FIO2 of 0.86 and a mean tidal volume of 153% in relation to baseline tidal volume. Both methods of hyperoxygenation and hyperinflation prevent hypoxia and maintain hemodynamic stability in patients without producing lung damage. The effectiveness of the manual resuscitator for administering high oxygen concentration and large volumes was confirmed.

[Endotracheal suctioning of secretions: effects of instillation of normal serum]. / Aspiración endotraqueal de secreciones: estudio de los efectos de la instilación de suero fisiológico.

Normal saline (NS) instillations in the trachea during the technique of endotracheal suctioning is an habitual practice although there is still some controversy about the benefits and harmful effects caused by this practice. This study was carried out with the objective to compare the effects of instillation or no instillation of NS during the aspiration technique on the oxygenation, amount of secretion obtained, and hemodynamical and ventilatory parameters. We studied 176 en dotracheal aspirations recorded in the post-operatory of 25 patients without previous pulmonary disease who underwent heart surgery. The aspiration was performed every two hours, according to the protocol of the study. Each patient was its own case and control, so the same patient was aspired altern actively; with and without NS instillation alternatively. Hemodynamical parameters (arterial blood pressure, heart rate), ventilatory parameters (fidal volume, peak inspiratory pressure, respiratory rate) and oxygenation parameters (PaO2, SaO2, SpO2) were analysed in all the samples. The amount of secretion obtained with both techniques was evaluated using weight calculus and total proteins. When analysing the results, we observed that the technique of en dotracheal aspiration causes increases of the Average Arterial Pressure; when NS is used in the aspiration there is a statistically significant decrease of PaO2. In the evaluation of the amount of secretions we obtained similar amounts with both techniques. Taking all this into account we recommend the elimination of systematical instillation of physiological serum from the protocols of endotracheal aspiration during this technique.