Tension Pneumothorax and Subcutaneous Emphysema Complicating Insertion of Nasogastric Tube
Table 3
Techniques used to confirm NG position.
The technique
Comment
Insufflation test
(i) Unreliable in small tubes or those with guide wire because of reduced airflow (ii) 20% false positive results [10, 11]
Gastric aspiration
(i) Normal gastric aspirate is clear to slightly yellow (ii) Altered in gastrointestinal bleeding and bowel obstruction
Aspirated fluid pH and bilirubin
(i) A pH less than 5 and bilirubin less than 5 mg/dL identified 98% of gastric sites (ii) A pH greater than 5 and bilirubin less than 5 mg/dL identified 100% of the respiratory sites [12]
Capnometry
Reported high specificity and sensitivity rate [13, 14]
Capnography
Capnography was as accurate as colorimetric device for detecting CO2 during placement of NG tubes [15]
Magnetic guidance
(i) Relatively new technique (ii) Rule out the presence of the NGT in stomach and lung