Effects of Endotracheal Tube Suctioning on Arterial Oxygen Tension and Heart Rate Variability

Abstract

The purpose of this study was to examine the autonomic mechanisms underlying changes in heart rate (HR) and systolic blood pressure (SBP) responses to endotracheal tube (ETT) suctioning and to compare the open versus closed methods of ETT suctioning on these measures and on arterial oxygen tension. Eighteen orally intubated participants, 33 to 82 years of age (M = 60 years), were randomized for the order of suctioning method. Arterial oxygen tension (PaO2) was measured before suctioning and 30 s and 5 min following suctioning. Beat-to-beat HR and arterial blood pressure data were collected for 10-min periods before and after suctioning. HR and SBP measures were analyzed before suctioning and 1 min and 5 min following suctioning. Although there were no significant effects of ETT suctioning on the autonomic mechanisms of HR modulation and no significant differences between the two methods of suctioning, ETT suctioning resulted in an increase in HR, SBP, and PaO2. However, there was a decrease in the parasympathetic nervous system indicator of HR variability (HRV) following open suctioning. All patients in this study maintained a PaO2 level 80 mm Hg, which may account for our lack of significant autonomic changes. This suggests that hyperoxygenation with 100% oxygen for a minimum of 1 min (or 20 breaths), as delivered by preoxygenation modes available on most microprocessor ventilators, should be the method of choice for all hyperoxygenation procedures to avoid a decrease in PaO2 following suctioning.

Intrauterine inflammation alters cardiopulmonary but not cerebral hemodynamics during open endotracheal tube suction in preterm lambs

“…An increase in HR during ETT suction, of similar magnitude to that in our study, has previously been reported in the preterm neonate (16). The cause of the increase in HR during ETT suction is postulated to be an autonomic response whereby a reduction in arterial oxygen tension is detected by the medulla, resulting in increased sympathetic efferent activity (16).…”

“…Endotracheal tube (ETT) suction is one of the most common interventions performed during respiratory support of preterm infants and is known to alter lung mechanics and systemic hemodynamics (3,(16)(17)(18)(19)(20). However, to our knowledge, the impact of prior exposure to intrauterine inflammation on these consequences is unknown.…”

“…The cause of the increase in HR during ETT suction is postulated to be an autonomic response whereby a reduction in arterial oxygen tension is detected by the medulla, resulting in increased sympathetic efferent activity (16). Open ETT suction may inhibit parasympathetic efferent activity, potentially causing an imbalance in autonomic regulation of HR (16). In our study, although ETT suction caused a greater reduction in preductal oxygen saturation in the LPS-exposed lambs, we did not observe a greater increase in HR.…”

The Effect of the Open and Closed System Suctions on Cardiopulmonary Parameters: Time and Costs in Patients Under Mechanical Ventilation

“…For example, changes in heart rate were significant in one study (9), which was in contrary to findings of the other investigations (10,11). In addition, changes in arterial oxygen saturation between two procedures were significant in two studies (11,12), while they were not significant in a study reported by Fernandez et al (10).…”

“…In recent years, several studies have compared the effects of the two suctioning methods (9)(10)(11)(12)(13)(14); however, the results are contradictory. For example, changes in heart rate were significant in one study (9), which was in contrary to findings of the other investigations (10,11).…”