Title: Nitrous Oxide (submitted by Dan Gingold, MD)<br/>Author: Mimi Lu<br/><a href='http://umem.org/profiles/faculty/185/'>[Click to email author]</a><hr/><div dir="ltr" style="line-height: 1.38; margin-top: 0pt; margin-bottom: 0pt;">
<span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Inhaled nitrous oxide gas (N</span><span style="font-size:8.8px;font-family:Arial;color:rgb(0,0,0);vertical-align:sub;white-space:pre-wrap;background-color:transparent">2</span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">O) or laughing gas, has a long history of use as anesthetics in dental and medical procedures, and can be used as a single agent for brief pediatric procedures. It has a short half-life of 5 minutes and is eliminated essentially non-metabolized through respirations. </span></span></div>
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<span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Inhaled N</span><span style="font-size:8.8px;font-family:Arial;color:rgb(0,0,0);vertical-align:sub;white-space:pre-wrap;background-color:transparent">2</span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">O has analgesic, anxiolytic, and amnestic properties. The mechanism of analgesia is hypothesized to be similar to that of opioids. Anxiolytic and sedative effect is similar to benzodiazepines and may involve GABA receptors.</span></span></div>
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<span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">The N</span><span style="font-size:8.8px;font-family:Arial;color:rgb(0,0,0);vertical-align:sub;white-space:pre-wrap;background-color:transparent">2</span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">O is typically given as a mixture of 30% N</span><span style="font-size:8.8px;font-family:Arial;color:rgb(0,0,0);vertical-align:sub;white-space:pre-wrap;background-color:transparent">2</span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">O with 70% O</span><span style="font-size:8.8px;font-family:Arial;color:rgb(0,0,0);vertical-align:sub;white-space:pre-wrap;background-color:transparent">2</span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">, although 50:50 mixture is also safe. In the ED, it is usually given as monotherapy, as this meets criteria for minimal sedation. Nitrous oxide concentrations > 50% meet criteria for moderate sedation. </span></span></div>
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<span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Complications are rare (most commonly, nausea/vomiting). Persistent use or abuse can be habit forming and has been associated with anemia and B12 deficiency. Rare side effects include asthma exacerbation, coughing, laryngospasm, cardiac events, and seizures. High nitrous concentrations can cause hypoxia and asphyxiation if sufficient oxygen isn’t supplied (FiO2 < 25%). </span></span></div>
<fieldset><legend>References</legend>
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<span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Alai, A. </span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);font-style:italic;vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Nitrous Oxide Administration</span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">. Medscape/emedicine. <a data-saferedirecturl="https://www.google.com/url?hl=en&q=http://emedicine.medscape.com/article/1413427-overview%23a1&source=gmail&ust=1472349540307000&usg=AFQjCNEQvd8gVcILTVumDPUJ17dLQlK0cg" href="http://emedicine.medscape.com/article/1413427-overview#a1" target="_blank">http://emedicine.medscape.com/<wbr />article/1413427-overview#a1</a></span></span></p>
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<span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);font-style:italic;vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Guideline for Monitoring and Management of Pediatric Patients During and After Sedation Diagnostic and Therapeutic Procedures</span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent">. American Academy of Pediatrics</span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);font-style:italic;vertical-align:baseline;white-space:pre-wrap;background-color:transparent">.</span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent"> 2011</span></span></p>
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<span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);font-style:italic;vertical-align:baseline;white-space:pre-wrap;background-color:transparent">Clinical Policy: Critical Issues in the Sedation of Pediatric Patients in the Emergency Department.</span><span style="font-size:14.6667px;font-family:Arial;color:rgb(0,0,0);vertical-align:baseline;white-space:pre-wrap;background-color:transparent"> Annals of Emergency Medicine, 51(4):378-399 (2008)</span></span></p>
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