Success rate of nasogastric tube insertion in anaesthetised, intubated, adult patients: A comparison between endotracheal tube cuff inflated and deflated states

Successful placement of nasogastric tube (NGT) in anaesthetised patients in operating room under General  Anaesthesia appears to be challenging one compared with its insertion in awake patients owing to lack of patients cooperation in the former. In the study a comparison was done between the nasogastric tube insertion with endotracheal tube cuff inflated state and that with endotracheal cuff deflated state. Comparison was done in terms of success in the first attempt, procedure time and incidence of adverse events.

In other words, the present study was conducted to compare the first-attempt success rate (primary outcome) of blind NGT insertion in neutral position between patients with ETT cuff inflated state and those with ETT deflated state; using “throat pack in-situ†as additional safety measure. Data from all 244 patients were available for analysis. Patients of both the two groups were comparable regarding their demographic parameters.

NGT insertion with ETT cuff deflated was feasible in a considerably greater number of patients compared with those where ETT cuff was kept inflated. In the current study, NGT insertion was possible in considerably more proportion of patients with the ETT cuff at deflated state compared with cuff at inflated state (approximated, 85% versus 55%, respectively). NGT placement with ETT cuff deflated state achieved about 30% more success rate.

The procedure time for NGT placement was considerably longer with ETT cuff inflated state compared to ETT cuff deflated state (38.1 versus 16.8 seconds, respectively.

In the present study, quicker placement of NGT was possible with the ETT cuff at deflated state than inflated state (approximated, 17 seconds versus 38 seconds, respectively). Thus, ETT cuff deflated state yielded about 20 seconds quicker placement of NGT.

Mean arterial pressure (MAP) and heart rate (HR) were noted at different time points during the procedure: baseline, before NGT insertion, and after NGT insertion. MAP and HR were found to be comparable at all observed time-points between the inflated cuff and deflated cuff groups. In the present study, heart rate and MAP were found comparable at all points of observations between the two groups. This translates into fact that the process of tracheal cuff deflation and re-inflation for a brief period had produced a non-significant hemodynamic response.

Although higher adverse events were observed with ETT cuff inflated state, the difference between the two groups was not significant when analyzed.

Limitations

In spite of every sincere effort the present study has some lacunae. This was a single-center study. Auscultation method was used for confirmation of NGT instead of more robust method such as ultrasonography, pH paper or the gold standard- the X-ray, owing to limited resource.  The study was carried out in a tertiary care hospital, so hospital bias cannot be ruled out. Further research could explore additional factors across the larger and more diverse patient groups.

CONCLUSION

Endotracheal cuff significantly affects the success rate of nasogastric tube insertion. The endotracheal tube cuff deflation-assisted technique improved the chances of successful nasogastric tube placement. It is also associated with reduced adverse events such as bleeding by avoiding multiple attempts.