References
Cortrak feeding tube placement: interpretation agreement of the ‘GI flexure’ system versus X-ray
Abstract
Background:
Blind (unguided) feeding tube placement results in 0.5% of patients suffering major complications mainly due to lung misplacement detected prior to feeding. Electromagnet-guided (Cortrak) tube placement could pre-empt such complications but undetected misplacements still occur due to incorrect trace interpretation. By identifying gastrointestinal (GI) flexures from the trace, ‘the GI flexure system’, it has been proposed that tube position can be interpreted.
Aims:
To audit agreement between standards of interpreting tube position: the Cortrak ‘GI flexure’ system versus X-ray.
Methods:
In 185 primary nasointestinal tube placements tube position determined by Cortrak trace interpretation (GI flexure) was retrospectively compared with radiological position in a blinded study.
Findings:
Radiological and Cortrak interpretation agreed in 92.2–98.3% of placements at different GI flexures. Discrepancy mainly occurred because some radiological images were unclear or did not cover all anatomical points.
Conclusion:
The GI flexure method of Cortrak interpretation appears safe but would necessitate prospective radiological investigation to definitively test equivalence.
About 6% of hospitalised patients require invasive nutrition support (Elia, 2015), the majority being nasogastric (NG) or nasointenstinal (NI) feeding. Of the blindly placed (unguided) feeding tubes, 1.5% enter the respiratory tract and, though most are detected and removed, one third (0.5%), result in pneumonia or pneumothorax (Taylor, 2018). Applying this to the 790 000 UK feeding tubes used in 2015 (NHS Improvement, 2016), would equate to nearly 4000 major complications (Taylor, 2018). Guided tube placement offers a means of detecting tube misplacement before the tube deeply enters the lung.
Cortrak is the most widely used bedside guided tube placement system (Medex, 2017). As shown in Figure 1, Cortrak consists of a receiver unit (a) that detects the tube guidewire's electromagnet (b) inside the body and the computer generates a screen trace (c) displaying the tube path frontally (A), patient's head at the top, from the side (B), head at the left and in cross-section (C). From the patient's perspective of ‘left and right’ the electromagnet is seen as a green dot tracing a yellow path on the screen. A ‘gastric trace’ moves vertically down the midline on the anterior (A) screen, turns left close to the xiphisternum (Figure 1, blue dot), then downward and then right into the intestine. The lateral screen path moves left to right, deep in the oesophagus, becoming shallow in the stomach, then deep intestinally. The cross-section screen shows depth from the abdominal surface and only displays a path once below the anterior screen horizontal line and to the right of the vertical midline.
Register now to continue reading
Thank you for visiting British Journal of Nursing and reading some of our peer-reviewed resources for nurses. To read more, please register today. You’ll enjoy the following great benefits:
What's included
-
Limited access to clinical or professional articles
-
Unlimited access to the latest news, blogs and video content