| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Alternately, some nurses insert suction catheters until resistance is met, and then pull the catheter back before applying suction. Unfortunately, meeting resistance and then "pulling back" before suctioning is not a solution.1 Research suggests that catheter contact rather than suction is responsible for mucosal damage.2 Studies in kittens have shown that inserting a catheter to resistance caused as much damage as insertion to resistance with the subsequent addition of suction.3 The effect of deep suctioning is tracheal mucosal damage, including epithelial denudement, hyperemia, loss of cilia, edema, fibrosis, and granuloma formation. This damage occurs when tissue is pulled into the catheter tip holes, and increases the risk of infection and bleeding for the patient. The purpose of suctioning is to remove secretions that are not accessible to bypassed cilia. Therefore, insertion of suction catheters only as far as the end of the placed ETT and TT has been recommended.2,4 Nurses may argue that though shallow suctioning appears to be less injurious to mucosa, it may also be a less effective method of removing secretions. However, there is no reason to suspect that mucocilliary transport below the tip of the ETT or TT should function abnormally. Therefore, larger volumes of aspirates would be collected in shallow-suctioning. Once deep-suction is initiated, the resulting damage to cilia may necessitate the need for continued deep suctioning.2 When an adult patient is endotracheally intubated, the distal portion of the tube sits between 3 and 7 cm above the carina.5 In neonates, the end of the ETT is frequently placed just 1 to 2 cm above the carina. Therefore, suction catheters should be inserted to a predetermined length. Passing suction catheters no further than 1 cm past the length of the ETT or TT can avoid contact with the trachea and carina.6 Resistance should not be met. If resistance is met, the suction catheter should be withdrawn at least 0.5 cm before applying suction.7 There are various methods of predetermining suction catheter depth1 and these methods should be incorporated into protocols for practice.
References
This reader brings up an important element of the suctioning procedure to which there is no consensus. The ideal suction catheter insertion depth through either an ETT or TT remains both an area of controversy and research interest. The reader is correct in that the adverse consequences of deep suctioning have been well described in the literature for many years.1–5 Animal research has demonstrated tracheobronchial trauma as a result of deep versus shallow suctioning.2 Limited data suggest that restricting suction catheter advancement to 1 cm beyond the tip of the artificial airway does not compromise secretion removal effectiveness.3
Clearly, mechanical trauma to the airway and mucosal surface is not just related to the suction catheter insertion depth, but also suctioning frequency, suction pressure levels used, ETT or TT movement, positive pressure effects of mechanical ventilation, and, to a lesser extent, suction catheter tip design, as most suction catheters in use today have incorporated safety features to minimize risk of tissue trauma when suction is applied. Van de Leur and coworkers4 recently studied 383 adults requiring endotracheal intubation randomized to either minimally invasive (29-cm suction catheter) or routine (49-cm suction catheter) catheter suctioning. They found no difference in the suction methods relative to duration of intubation, intensive care unit stay, intensive care unit mortality, and incidence of pulmonary infection. Suction-related adverse events (increased pulse pressure rate, decreased saturation via pulse oximetry, blood in mucus, and systolic blood pressure increase) occurred more frequently with routine deep suctioning versus shallow suctioning. In another recent study5 of 27 high-risk infants randomized to either shallow or deep ETT suctioning, there were no significant differences between the 2 methods in either heart rate and oxygen saturation before, during, or after ETT suction.5
The vast majority of studies on this subject have focused on infants and neonates receiving ventilation. Spence and coworkers6 conducted an extensive literature search of controlled trials using random or quasi-random allocation of neonates receiving ventilatory support via an ETT to either deep or shallow endotracheal suctioning. They found that there was no evidence to conclusively answer the question as to whether shallow suctioning is preferred over deep suctioning in neonates and infants, and further high-quality research would be required. Given the published and anecdotal evidence of adverse effects of deep suctioning, this type of proposed study would ethically only be considered when the standard practice includes deep suctioning technique.
Indeed, as noted by other researchers interested in suctioning techniques and airway management, collaborative, research-based policies and procedures must be developed and implemented to ensure best practices for intubated patients.7 There are instances when deep suctioning may be reasonable such as the use of directional-tip catheters for suctioning the left main stem bronchus. Several suction catheter manufacturers have added depth markers along the catheters (both open and closed suction catheter systems) to aid clinicians who wish to limit insertion depth. Many hospitals utilize pre-measured suction catheter depth guides or cards at the bedside. This may be particularly helpful with neonatal and pediatric ETTs and TTs. Until a more definitive answer to this question is known, the available evidence would favor avoiding routine deep suctioning practice.
References
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
