End-Tidal CO2 (etCO2) and pH in the Correct Naso-gastric Tube Placement

Completed

• Conditions: Blood Gas Monitoring, Transcutaneous; pH; Gastric Feeding Tube
• Interventions: Other: etCO2; Other: pH

• Registration Number: NCT03934515
• Lead Sponsor: Clinica Luganese Moncucco

Brief Summary

The laying of a naso-gastric tube is an extremely common event in intensive medicine; although standard naso-gastric tube laying is performed at the patient's bedside, this procedure is not without risk. Through the use of methods already used in the clinical field, of daily use, we want to identify the threshold value between tracheal and esophageal etCO2 (group A) and the threshold value between gastric and esophageal pH (group B).

Detailed Description

Numerous methodologies have been evaluated to recognize the correct positioning of NGT at the gastric level, including different clinical techniques (such as gastric auscultation, aspiration of the NGT), ultrasound techniques, etc. Actually, the diagnostic gold standard is the thoraco-abdominal anterior-posterior radiography, which is considered the only non-invasive method capable to confirm the correct pose of the NGT at intra-diaphragmatic level. This method, however, even if it is non-invasive, requires the use of ionizing radiation (4 micro-Sievert (uSv) for radiography) which could be repeated multiple time for the same patient; NGT may need to be repositioned several times during the same hospital stay, increasing patient exposure to ionizing radiation and, potentially, also the health workers exposure.

The aim is to identify into the group A the threshold value between tracheal and esophageal etCO2 and into the group B the theshold value between gastric and esophageal pH.

Phase A: etCO2 measurement will be collected 1. after intubation, when the tube is inserted into the endotracheal tube, before proceeding with the aspiration of secretions and 2. once the NGT has been inserted, by a probe located at the end of the tube.

Phase B: pH measurement will be collected at the end of the procedure, once the NGT is inserted, at 1.a distance of 25 cm from the mouth (oesophageal site) and at 2. a distance of 40 cm (gastric site), aspirating the gastric contents and measuring on specific litmus paper.

Study Timeline

• Study First Submitted: 2019-04-26
• Study First Submitted QC: 2019-04-30
• Study First Posted: 2019-05-02
• Study Start: 2020-11-01
• Primary Completion: 2021-04-01
• Study Completion: 2021-08-01
• Status Verified: 2021-10
• Last Update Submitted: 2021-10-04
• Last Update Posted: 2021-10-05

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 85

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Group A - etCO2	etCO2	At the end of the anaesthesia , as usual, the secretions are aspirated with a suction tube of 18 Fr of caliber (diameter 6 mm). When the tube is inserted into the endotracheal tube, before proceeding with the aspiration of the secretions, a capnometer is attached to its outer end, measuring the etCO2 value for 10-15 seconds. At the end of the measurement, authors proceed with the aspiration of the secretions as usual. Authors then proceed with the laying of a NGT according to local protocols. Also in this case, once the NGT has been inserted, the etCO2 is measured at the end of the probe for 10-15 seconds. At the end of the measurement, the capnometer can be detached, as a standard procedure, and the NGT can be used as usual. At the end of the procedure, therefore, for each patient, two values of etCO2 are acquired which will allow to obtain two "populations of values" of the etCO2: the values recorded at the endotracheal level and the one recorded at the oesophageal level.
Group B - pH	pH	At the end of the anaesthesia , once the NGT is inserted, the pH is measured by aspirating the gastric contents and measuring on specific litmus paper the pH values, both at a distance of 25 cm from the mouth (oesophageal site) and at a distance of 40 cm (gastric site). At the end of the procedure, for each patient two values of pH are acquired which will allow to obtain two pH "value populations": a value at oesophageal level and a value at the gastric level.

Primary Outcome Measures

Name	Time	Method
pH	30-60 seconds	to find a threshold value of pH collected when the NGT is positioned in the esophagus and in the stomach.
etCO2 level	30-60 seconds	to find a threshold value of etCO2 collected when the NGT is well positioned in trachea

Secondary Outcome Measures

Name	Time	Method
etCO2 level in chronic obstructive pulmonary disease (COPD) patients	30-60 seconds	subanalysis for the threshold value in the group with chronic obstructive pulmonary disease (COPD)
pH in patients taking proton pump inhibitors (PPIs)	30-60 seconds	identify patients taking proton pump inhibitors (PPIs) and perform a sub-subanalysis for the threshold value in the group with already diagnosed gastro-esophageal reflux disease.

Trial Locations

Locations (1)

Clinica Luganese Moncucco; 🇨🇭 Lugano, Switzerland