The Effect of Suction Method, Catheter Size, and Suction Pressure on Lung Volume Changes During Endotracheal Suction in Piglets

Abstract

ABSTRACT:We aimed to identify the effect of suction pressure and catheter size on change in lung volume during open and closed endotracheal suction. Anesthetized piglets (n ϭ 12) were intubated with a 4.0-mm endotracheal tube. Lung injury was induced with saline lavage. Three suction methods (open, closed in-line, and closed with a side-port adaptor) were performed in random order using 6, 7, and 8 French gauge (FG) E ndotracheal tube (ETT) suction is performed periodicallyin patients receiving mechanical ventilation, to maintain a patent airway and facilitate ventilation. Although necessary, it is associated with adverse sequelae including atelectasis, hypoxia, and cardiovascular instability (1-4), attributed in part to loss of lung volume. Volume loss can arise from breaking the ventilator circuit for "open" suction and aspiration of gas after application of negative pressure. Closed suction techniques, performed without disconnecting the ventilator circuit, have been widely adopted to reduce the adverse effects of suction (5).Two closed suction techniques are available: in-line systems, in which a suction catheter, enclosed in a plastic sheath, is incorporated into the ventilator circuit; and side-port adaptors, Y-shaped connectors placed between the ETT and the ventilator circuit, through which a suction catheter is passed. Few studies have compared the two methods, and there is little evidence to support the use of one over the other (6 -8). Both techniques have been shown to result in greater physiologic stability in neonates (9,10), and less loss of lung volume in adults (7,11) and children (12) than open suction, although large volume losses have been recorded with both closed and open methods (7,12,13). In the only neonatal study to date comparing lung volume changes, there was no difference in volume loss between open and closed suction during either conventional or high-frequency oscillatory ventilation (HFOV), and wide variation in losses with both methods (14).The contribution to volume loss of factors other than suction method remains to be elucidated. At least in vitro, suction catheter size and suction pressure have been implicated in determining tracheal pressure during suction (15-17), the presumed precursor to volume loss. Whether tracheal pressure changes result in clinically observable effects is unclear (4,18 -20) and there is no consensus on appropriate catheter sizes or suction pressures for clinical use in children or neonates (21)(22)(23)(24)(25)(26)(27). No studies have investigated the impact of these factors on lung volume changes.The aim of this study was to investigate the effect of suction method (open, closed in-line, and closed with a side-port adaptor), catheter size, and suction pressure on lung volume changes during endotracheal suction. Comparisons were made during both conventional, time-cycled pressure-limited ventilation (TCPLV) and HFOV. MATERIALS AND METHODSThe study procedures were approved by the Murdoch Childrens Research Institute Animal Ethics Committee. It was...

Effect of Application of Endotracheal Suction Guidelines on Cardiorespiratory Parameters of Mechanically Ventilated Patients

“…It can be related to that in the study group, there was increased probabilities of improving inspired volume of air as evidenced by decreased time of patient's disconnection from ventilator, suctioning was done for 10 to 15 seconds, external diameter of the suction catheter was less than half of the internal diameter of the patient's tracheal tube, and suction pressure was controlled from 120 to 150 mmHg. Copnell B. et al (22) reported that the effect of suction method, force, and tube size on lung volume changes during ES in piglets and found that closed suction preserved more lung volume than open one.…”

“…It was a developed tool by the researcher after reviewing the related literature (2,3,10,(21)(22)(23) . It was used to gather data of cardiorespiratory parameters to compare between actual routine method practiced by nurses in ICU and guidelines based method that are restricted to evidenced based recommendations.…”

“…The tool was developed by the researcher based on reviewing the relevant literature (2,3,10,(21)(22)(23) . The tool was reviewed for content validity, by professors in the following fields: critical care nursing, critical care medicine, anaesthesia and medical biostatistics.…”

Pediatric Airway Maintenance and Clearance in the Acute Care Setting: How To Stay Out of Trouble

“…In open suctioning, volume loss is independent of catheter size. 56 This may be explained by the probable presence of turbulent flow between the ETT and suction catheter during closed suctioning. 52 The concept that closed suctioning is better because it prevents volume loss may be incorrect.…”

“…Not surprisingly, open suctioning produced a greater lung-volume loss. 56 Note, however, that 4 of the 10 HFOV patients were receiving muscle relaxants, and those paralyzed patients had the longest recovery times. 53 This could correlate to the fact that paralyzed patients are often sicker.…”