Objectives Nasogastric (NG) intubation is one of the most common procedures performed in the emergency department (ED) and other hospital settings. The aim of this study was to compare the level of pain during NG tube insertion in groups receiving local ketamine plus water-soluble lubricating gel and water-soluble lubricating gel alone (the latter is the common practice in our hospital). It was hypothesised that ketamine has local anaesthetic effects in reducing the pain of NG tube insertion in the ED.

Methods This prospective double-blind randomised clinical trial was performed on alert haemodynamically stable subjects aged >18 years who required NG tube placement for diagnostic or therapeutic purposes in the ED of a teaching hospital during January and June 2008. The subjects were divided into two groups using randomised allocation software. The ketamine group received intranasal ketamine, while an equivalent volume of sterile water was instilled into the nasal cavity in the control group. The same amount of lubricating gel was used in both groups. The pain of NG tube placement was measured using a standard 100 mm visual analogue scale (VAS). The physician was asked to evaluate the difficulty of the procedure using a 5-point Likert scale.

Results Seventy-two subjects were enrolled in the study (36 subjects in each group). There was a significant difference between the pain score of the ketamine and control groups (19.03±3.56 vs 33.33±5.31), while the difficulty score was not statistically different between the two groups (2.39±1.25 vs 2.78±1.56).

Conclusion Intranasal ketamine is an effective agent in reducing pain during NG tube insertion among patients without serious underlying illness.