Systematic review: the use of nitrous oxide gas for lower gastrointestinal endoscopy

Abstract

SUMMARYBackground Nitrous oxide gas (N 2 O) has been proposed as an alternative to intravenous (i.v.) analgesia in patients undergoing lower gastrointestinal endoscopy.

The effect of nitrous oxide on intra‐ocular pressure in healthy adults*

“…Nitrous oxide is a weak volatile anaesthetic with a minimum alveolar concentration (MAC) of 104%, achievable only in hyperbaric environments [17]. Nitrous oxide is capable of producing mild sedation and analgesia, and has been shown to be safe and effective for use in a variety of practice environments including colonoscopy, transoesophageal echocardiography, transrectal prostate biopsy, emergency department procedures and labour pain management [10][11][12][13][14]18].…”

“…An ideal sedative agent would not clinically affect the patient's IOP, as this could lead to inappropriate management decisions with potential long-term visual consequences. Nitrous oxide has been shown to be safe and effective for sedation and analgesia during a variety of procedures [10][11][12][13][14]. In this study, we investigated the effect of N 2 O on the IOP of healthy adult volunteers as a preliminary step to exploring the utility of N 2 O for use in 'examinations under anaesthesia' (EUA) for the measurement of IOP.…”

Maintaining Quality in Endoscopy

“…The inhalational agent nitrous oxide is also used for sedation and analgesia in colonoscopy due to its rapid onset of action and short recovery time. Randomised trials comparing nitrous oxide to intravenous opiates with or without benzodiazepines failed to show a clear difference between the two groups in terms of pain relief, reaction times or complex psychomotor co-ordination (Lindblom, Jansson et al 1994;Saunders, Fukumoto et al 1994;NotiniGudmarsson, Dolk et al 1996;Trojan, Saunders et al 1997;Forbes and Collins 2000;Maslekar, Gardiner et al 2009;Welchman, Cochrane et al 2010). Patients given intravenous sedation had worse recall of the procedure and reduced manual dexterity compared to those given nitrous oxide (Lindblom, Jansson et al 1994;Saunders, Fukumoto et al 1994;NotiniGudmarsson, Dolk et al 1996;Trojan, Saunders et al 1997;Forbes and Collins 2000;Maslekar, Gardiner et al 2009;Welchman, Cochrane et al 2010).…”

“…Randomised trials comparing nitrous oxide to intravenous opiates with or without benzodiazepines failed to show a clear difference between the two groups in terms of pain relief, reaction times or complex psychomotor co-ordination (Lindblom, Jansson et al 1994;Saunders, Fukumoto et al 1994;NotiniGudmarsson, Dolk et al 1996;Trojan, Saunders et al 1997;Forbes and Collins 2000;Maslekar, Gardiner et al 2009;Welchman, Cochrane et al 2010). Patients given intravenous sedation had worse recall of the procedure and reduced manual dexterity compared to those given nitrous oxide (Lindblom, Jansson et al 1994;Saunders, Fukumoto et al 1994;NotiniGudmarsson, Dolk et al 1996;Trojan, Saunders et al 1997;Forbes and Collins 2000;Maslekar, Gardiner et al 2009;Welchman, Cochrane et al 2010). All studies showed reduced post-procedural stay in patients given nitrous oxide compared to intravenous sedation (Lindblom, Jansson et al 1994;Saunders, Fukumoto et al 1994;NotiniGudmarsson, Dolk et al 1996;Trojan, Saunders et al 1997;Forbes and Collins 2000;Maslekar, Gardiner et al 2009;Welchman, Cochrane et al 2010).…”

“…Patients given intravenous sedation had worse recall of the procedure and reduced manual dexterity compared to those given nitrous oxide (Lindblom, Jansson et al 1994;Saunders, Fukumoto et al 1994;NotiniGudmarsson, Dolk et al 1996;Trojan, Saunders et al 1997;Forbes and Collins 2000;Maslekar, Gardiner et al 2009;Welchman, Cochrane et al 2010). All studies showed reduced post-procedural stay in patients given nitrous oxide compared to intravenous sedation (Lindblom, Jansson et al 1994;Saunders, Fukumoto et al 1994;NotiniGudmarsson, Dolk et al 1996;Trojan, Saunders et al 1997;Forbes and Collins 2000;Maslekar, Gardiner et al 2009;Welchman, Cochrane et al 2010). Carbon dioxide insufflation has been recommended during colonoscopy as carbon dioxide is highly soluble and can thus be passively absorbed by the colon and excreted by the lungs, thereby minimizing intra-procedural and post-procedural discomfort (Williams 1986).…”