Nasogastric tube errors – 2
We write in reference to the special feature article regarding nasogastric (NG) tube errors. The guidance that you quote from the NPSA is very difficult to implement in practice in many clinical circumstances. There are unintended consequences that expose patients to risks from repeated doses of radiation with multiple x-rays and failure of delivery of nutrition or medication for long periods; as well as increasing healthcare costs.
The evidence quoted in the NPSA guidance is weak and focuses on small numbers of serious adverse events, while ignoring very large denominator numbers of tens of thousands of patients who receive NG feed to put numbers into perspective.
While we were pleased to see an article highlighting this important and preventable cause of morbidity and mortality in healthcare, there was a vital omission in the discussion: the implications of acid suppressing drugs for confirmation of NG tube position. Many critical incidents occurring with misplaced NG feeding tubes occur in ventilated critically ill patients.
Many critical incidents occurring with misplaced NG feeding tubes occur in ventilated critically ill patients
This group of patients frequently receive prophylaxis against stress ulceration with either an H2 antagonist or proton pump inhibitor, in line with national and international standards of care for ventilated patients. The administration of these drugs frequently results in gastric aspirate that is above pH 5.5, necessitating a chest x-ray as proof of correct NG placement.
The bullet point relating to repeat checks states that NG tubes “can be dislodged so they should be checked every time they are used, by aspirating and confirming a low pH, and only x-raying if this is not the case” – this needs further clarification. In a group with increased gastric pH this would mean a chest x-ray every time an NG drug is administered – possibly multiple times over the course of a day.
We would suggest that for ventilated critically ill patients the wording should be changed from “every time they are used” to “if there is any suspicion of displacement”. This can be aided by ensuring that the cm marker at the nostril following insertion is clearly documented and checked every time the NG tube is used.
The guidance makes the maintenance of regular adequate enteral nutrition and medication administration impossible for large groups of patients, and should be revised
The guidance also has implications that extend far beyond critical care. There are many patients in community hospitals and rehabilitation units receiving NG feeding, who will be receiving concurrent acid suppressing drugs. There are large numbers of confused patients who repeatedly pull out NG feeding tubes and multiple x-rays on a daily basis and who are impossible to sustain. In many of these units there may not be direct access to x-ray facilities available.
The guidance makes the maintenance of regular adequate enteral nutrition and medication administration impossible for large groups of patients, and should be revised. The major difficulty with that is that the NPSA was abolished last year and there is no mechanism for revision.
Dr Neil Young and Dr Brian Cook, UK