CLINICAL
NASOGASTRIC TUBE FEEDING: AN OVERVIEW Nasogastric (NG) feeding is the most common method of providing short-term (generally less than 30 days) artificial nutrition support. This article looks at considerations and management of feeding with an NG tube (NGT). In my career to date, I am aware of one never event that happened in relation to a misplaced NGT. As a result, I am extremely mindful of ensuring all checks are completed to confirm NGT position before it is used. An NGT is a tube inserted through the nose and into the stomach via the oesophagus. It is used for administration of fluids, medication, nutrition, gastric aspiration and decompression. The size of NGTs used for feeding should be between 6 and 12 French. In line with National Patient Safety Agency (NPSA) guidance, NGTs used for feeding should be radio-opaque along their entire length, be CE marked and have external visual length markings.1 NICE 2006 guidelines state that NG feeding should only be initiated in people who are malnourished or at risk of malnutrition and who have inadequate or unsafe oral intake and a functioning accessible GI tract. Following the NPSA 2011 alert, before a decision is made to insert an NGT, an assessment should be undertaken to identify whether NG feeding is appropriate for the patient and the rationale for any decision should be recorded in the patient’s medical notes. Following NICE guidance, NG feeding should be stopped when the patient is established on adequate oral intake.2 If the individual is likely to require long-term enteral feeding then they should be considered for gastrostomy feeding.
Louise Edwards Community Team Lead/Specialist Dietitian
TO FEED OR NOT TO FEED?
Enteral tube feeding is considered to be a medical treatment and, thus, initiating or withholding nutrition is, therefore, a medical decision which is always made taking the wishes of the patient into account. 3 Following the NPSA 2011 alert, ‘the decision to insert an NGT for the purpose of feeding must be made following careful assessment of the risks and benefits by at least two competent healthcare professionals, including the senior doctor responsible for the patient’s care’. The dietitian is generally one of these healthcare professionals. For those individuals with capacity, the purpose of the insertion of an NGT should be explained to the patient along with the risks associated with it. Following this discussion, the patient should be allowed time to consider their decision and consent if they wish the procedure to go ahead. Where individuals demonstrate a lack of capacity, a best-interest decision should be made by the multidisciplinary team responsible for the patient’s care. A best-interest meeting may need to be coordinated involving the patient’s next of kin, an advocate, or an independent mental capacity advocate (IMCA).
Louise is a Specialist Dietitian working for the Central Cheshire Integrated Care Partnership (CCICP). She is the Community Team Lead and is passionate about service improvement.
REFERENCES Please visit: https://www. nhdmag.com/ references.html
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Meeting nutritional needs in critically ill patients JUST BECAME EASIER.
NEW
NUTRISON PROTEIN INTENSE is the newest addition to our high protein range – the first and only whole protein tube feed, high in protein, that fully meets critical care guidelines.1–5 Accurate at time of publication September 2019. This information is intended for Healthcare Professionals only. Nutrison Protein Intense is a Food for Special Medical Purposes for the dietary management of disease related malnutrition in critically ill patients and must be used under medical supervision. References: 1. Singer P, et al. 2019; 38(1):48–79. 2. McClave SA, et al. 2016; 40:159–211. 3. Kreymann KG, et al. 2006; 25:210–223. 4. Dhaliwal R, et al. 2014; 29:29–43. 5. Sioson MS, et al. 2018; 24:156–164.
CLINICAL Table 1: Common conditions that result in NG feeding Swallowing disorders because of neurological conditions Preoperative nutritional support Cachexia Chronic infections Malabsorption Lowered consciousness level Table 2: Contraindications for NG feeding Maxillofacial disorders Unstable cervical spinal injuries Nasal/pharyngeal/oesophageal obstruction or ulceration Choanal atresia Tracheoesophageal fistula Oesophageal/pharyngeal pouch Oesophageal strictures or other abnormalities of the oesophagus Oesophageal tumours or have undergone oesophageal surgery Basal skull fractures Oropharyngeal tumours or have undergone oropharyngeal surgery Post laryngectomy Actively bleeding oesophageal or gastric varices Gastric outflow obstruction Intestinal obstruction This list is not exhaustive, adapted from NNNG, 2016.15 INSERTION OF AN NG FEEDING TUBE
NGTs are commonly inserted by doctors, nurses and allied health professionals. The healthcare professional placing the tube should have completed training and demonstrated and achieved a competency in NGT insertion in line with the trust’s policy.3,4 NGTs are commonly placed at bedside, but there may be circumstances where radiology supports with placement. Misplaced NGTs are a contributing cause of never events. This is in relation to the introduction of fluids, or medication into the respiratory tract, or pleura via a misplaced NGT (or orogastric tube). Never events are considered ‘wholly preventable where guidance or safety recommendations, which provide strong systemic protective barrier, are available at a national level, and should have been implemented by all healthcare providers’.5 24
A review of never events from NHS England and NHS improvement for this year 1st April to 31st August, found 11 events of misplaced NG feeding tubes. With these incidents, feed was administered when the NG tube was in the respiratory tract. The NPSA alert 2016 titled Nasogastric tube misplacement: continuing risk of death and severe harm, found that the reasons for which never events occur in relation to NGT misplacement are: • misinterpretation of X-rays by medical staff who had not received the competency-based training required by the 2011 NPSA alert; • nursing staff error with pH testing; • unapproved tube placement checking methods; • communication failures resulting in tubes not being checked.
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CLINICAL It is possible that the patient may not be symptomatic from an NGT being inserted into the airway for several hours post placement and after multiple feedings.6 Confirming the position of the tip of the NGT is essential, since the tube may be displaced even when its external appearance (outside the face) remains unchanged.7 Checking the position of the NGT is paramount to prevent harm. BAPEN recommends repeat placement checks of the tube before administering each feed, before giving medication and at least once daily. NNNG 2016 also recommends pH testing following episodes of vomiting, retching or coughing. When there is evidence of tube displacement (ie, length of tube at nostril has changed), then a check of the placement of the tip of the NGT is required. Any new or unexplained respiratory symptoms, or a reduction in oxygen saturation, would also be indicative of an NGT placement check.4 Throughout history, different methods have been used to confirm position of the NGT. NPSA 2011 conducted a systematic review to look at the different methods of checking NGT position so that recommendations could be made as to the recommended approach of confirming position. The NPSA recommend that pH testing is the first-line method for confirmation of NGT placement. NICE 2006 guidance reiterates that testing gastric aspirate with pH-graded paper is first line for confirming NGT placement with an X-ray being taken if necessary. The pH reading must be 5.5 or below before feed, fluid or medication can be administered via the NGT.8 pH testing is four times less expensive than X-ray confirmation.9 Local protocols should be in place for ‘how to proceed when the ability to make repeat checks of the tube position is limited by the inability to aspirate the tube, or the checking of pH invalid because of gastric acid suppression’.2 A method previously used for confirming NGT position was auscultation or the ‘whoosh’ test. This is where a stethoscope was placed over the epigastrium to listen for a ‘whoosh’ sound as air is syringed through the NGT.7 This method falsely indicated gastric position of NGTs,10 as sounds may be transmitted to the epigastrium
when the tube is positioned in the lung, oesophagus, stomach, duodenum or proximal jejunum.6 Testing of NGT aspirate with litmus paper was another method used. It was thought that if blue litmus paper turned pink with the NGT aspirate then it would indicate that the aspirate was acidic and, thus, suggest gastric placement of the tip of the NGT. However, blue litmus paper is reported to turn pink with a pH of 6 or 7 and, therefore, cannot distinguish between gastric or bronchial aspirates.11 Other methods for confirming NGT position include biochemical markers with PH testing, capnography and electromagnetic tracing, etc.12 CONSIDERATIONS FOR DISCHARGE
In some circumstances, the patient may be discharged home to continue with NG feeding. Such examples could be palliative NG feeding and preoperative nutrition support, etc. As I have highlighted above, misplacement of an NGT can be fatal and, therefore, prior to discharge, a full multidisciplinary supported risk assessment should be made and documented before the patient is discharged from acute care to the community.1 SECURING THE NGT
A hypoallergenic tape should be used to secure the NGT to the patient’s nose or cheek to reduce risk of displacement.4 If there is repeated displacement of the NGT, a nasal retention device may be considered. Another fixation device to discourage patients from pulling on their NGT and to aid in securing it in position at the nostril, is a nasal bridle. Reports show that 40% of NGTs are dislodged.13 A nasal bridle is an effective way of securing a patient’s NGT, retaining the provision of nutrition to the patient. Most Trusts have their own local policy for the criteria necessary in order for patients to meet NGT placement (eg, pulled out two NGTS within 48 hours). There are considerations for when a nasal bridle would be contraindicated, such as restlessness and agitation leading the individual to still pull at the tube.14 Capacity and ethics need to be considered when deciding if a nasal bridle is appropriate.
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Click here to read the Dec/Jan issue Articles include: • Weaning preterm babies
• Nasogastric tube feeding • Fussy eating in toddlers • Constipation and treatment • Popular liquid diets
• Plant-based diets • Care caterers in social care • Follow-on formula new regulations