EARN This course was written for dentists, 3 CE dental hygienists, CREDITS and dental assistants. © Oneblink | Dreamstime.com Nitrous oxide: Use and safety (second edition) A Peer-Reviewed Publication Written by Ian Shuman, DDS, AFAAID, MAGD PUBLICATION DATE: DECEMBER 2019 EXPIRATION DATE: NOVEMBER 2022 SUPPLEMENT TO ENDEAVOR PUBLICATIONS EARN This continuing education (CE) activity was developed by the PennWell dental group, an operating unit of Endeavor Business 3 CE Media, with no commercial support. This course was written for dentists, dental hygienists, and dental CREDITS assistants, from novice to skilled. Educational methods: This course is a self-instructional journal and web activity. Provider disclosure: Endeavor Business Media neither has a leadership position nor a commercial interest in any products or services discussed or shared in this educational activity, nor with the commercial supporter. No manufacturer or third party had any input in the development of the course content. Requirements for successful completion: To obtain three CE credits for this educational activity, you must pay the required fee, review the material, complete the course evaluation, and obtain a score of at least 70%. CE planner disclosure: Laura Winfield, Endeavor Business Media dental group CE coordinator, neither has a leadership nor commercial interest with the products or services discussed in this educational activity. Ms. Winfield can be reached at lwinfield@ endeavorb2b.com Educational disclaimer: Completing a single continuing education course does not provide enough information to result Nitrous oxide: Use and safety in the participant being an expert in the field related to the course topic. It is a combination of many educational courses and clinical experience that allows the participant to develop skills and (second edition) expertise. Image authenticity statement: The images in this educational ABSTRACT activity have not been altered. In dentistry, nitrous oxide is the most commonly used inhalation anxiolytic Scientific integrity statement: Information shared in this CE course is developed from clinical research and represents the most and sedation adjunct. It reduces anxiety, pain, and memory of the treatment current information available from evidence-based dentistry. experienced and is a valuable component of the armamentarium available to Known benefits and limitations of the data: The information clinicians. When used correctly, it is predictable, effective, and safe. presented in this educational activity is derived from the data and information contained in reference section. The research data is extensive and provides a direct benefit to the patient and LEARNING OBJECTIVES improvements in oral health. This clinical study will provide the dental professional with the steps needed Registration: The cost of this CE course is $59 for three CE credits. to deliver nitrous oxide in a safe and efficacious manner. Cancellation and refund policy: Any participant who is not 100% satisfied with this course can request a full refund by contacting After reading this continuing education course, the reader should be able to: Endeavor Business Media in writing. 1. Refer to the history of nitrous oxide Endeavor Business Media 2. Understand the properties of nitrous oxide Nationally Approved PACE Program 3. Know the safety recommendations Provider for FAGD/MAGD credit. Approval does not imply acceptance 4. Have the ability to deliver nitrous oxide in a safe manner, and know the by any regulatory authority or AGD endorsement. 11/1/2019 to 10/31/2022. contraindications Provider ID# 320452 Endeavor designates this activity for 3 continuing educational credits. Dental Board of California: Provider 4527, course registration number CA code: 03-4527-15425 “This course meets the Dental Board of California’s requirements for 3 units of continuing education.” Endeavor Business Media is designated as an approved PACE program provider by the Academy of General Dentistry (AGD). The formal continuing dental education programs of this program provider are accepted by the AGD for fellowship, mastership, and membership maintenance credit. Approval does not imply acceptance by a state or provincial board of dentistry or AGD endorsement. The current term of approval extends from (11/1/2019) to (10/31/2022) Provider ID# 320452. Endeavor/PennWell Corporation is designated as an approved Provider by the American Academy of Dental Hygiene Inc. # AADHPNW (January 1, 2019–December 31, 2020). Approval does not imply acceptance by a state or provincial Board of Dentistry. Licensee should maintain this document in the event of an audit. Endeavor Business Media is an ADA CERP–recognized provider ADA CERP is a service of the American Dental Association to assist dental professionals in identifying quality providers of continuing dental education. ADA CERP does not approve or endorse individual courses or instructors, nor does it imply acceptance of credit hours by boards of dentistry. Go online to take this course. Concerns or complaints about a CE provider may be directed to the provider or to ADA CERP at ada. DentalAcademyofCE.com org/goto/cerp. QUICK ACCESS CODE 15425 DENTAL ACADEMY OF CONTINUING EDUCATION INTRODUCTION capable of destroying physical pain, it may temperatures), irrespective of the size of the Officially known as dinitrogen monoxide by probably be used with advantage during tank or the quantity of nitrous oxide remain- the International Union of Pure and Applied surgical operations in which no great effu- ing in it. Once there is no liquid phase remain- Chemistry (IUPAC), nitrous oxide (an oxide sion of blood takes place.”7 Unfortunately, ing in the tank, the pressure will begin to drop. of nitrogen) is a small, inorganic chemical surgeons of this era failed to take note, and The shoulder of the nitrous oxide cylinder is 1 molecule with the formula N2O. It is com- the gas was used primarily for public enter- marked with information including, but not monly known as “laughing gas, nitrous, nitro, tainment. Inhalation of nitrous oxide for restricted to, the brand, manufacturer’s test NOS, sweet air, protoxide of nitrogen, and recreational use began as a phenomenon date and serial number, inspector’s mark, hyponitrous oxide.”2 At room temperature, among the British upper class in 1799, and Department of Transportation specifications, “it is a colorless, nonflammable gas, with a they were known as “laughing gas parties.”8 and service pressure. See figure 1. slightly sweet odor and taste,”2 and it’s used In 1844, American dentist Horace Wells in surgery and dentistry for its anesthetic realized the therapeutic applicability of the PHYSIOLOGY properties and analgesic effects.3 gas after self-administration.9 His associate, The mechanism by which anesthetic gases It is known as “laughing gas” due to its William Morton, became its chief proponent produce general anesthesia is unknown. euphoric effects, a property that has led to and drove the use of inhalation anesthetic The leading theory suggests that they bind its recreational use as a dissociative anes- forward. Today, nitrous oxide is used in den- to proteins within neuronal membranes and thetic.4,5 As an industrial gas, it is used as tal facilities worldwide.10 modify ion fluxes and subsequent synap- an oxidizer in rockets, a boost for race car tic transmission. Unlike other anesthetics, engine output, and in the food industry as a PHYSICAL PROPERTIES “nitrous oxide produces a mild analgesic foaming agent for whipped cream.2 Nitrous oxide gas is produced by heating effect at subanesthetic concentrations.”12,13 ammonium nitrate crystals to 250°C, then The mechanism for this effect most likely HISTORY scrubbing, compressing, and liquefying the involves an interaction with the endoge- The history of nitrous oxide begins in 1772 gas before placing it in pressurized tanks.11 nous opioid system because it is abolished with its isolation by theologian and scientist Present as both liquid and gas in the tank, it by administration of the opioid antagonist, Joseph Priestly.6 In 1798, Humphry Davy, an vaporizes at room temperature as it is used. naloxone. The strongest evidence for these English chemist, noted the analgesic effects The color of the nitrous oxide tank varies by analgesic effects is that nitrous oxide stim- of nitrous oxide. In 1800, Davy published country. In the United States and Canada, ulates release of enkephalins, which bind the history, chemistry, physiology, and rec- nitrous oxide tanks are blue, with the pres- to opioid receptors that trigger descending reational use of nitrous oxide. In his text, sure measuring approximately 750 pounds noradrenergic pathways. The most common Davy mentioned, “As nitrous oxide appears per square inch (psi) at 70°C (less at lower estimate of analgesic efficacy suggests that FIGURE 1: Nitrous oxide cylinder in North America DentalAcademyOfCE.com 3 DENTAL ACADEMY OF CONTINUING EDUCATION “30% nitrous oxide delivered by full mask is clinical, however. Hypoxemia is significant CHART 1: Indications and relative/absolute equivalent to 10 to 15 mg morphine.”12 for only a matter of minutes and has been contraindications for nitrous oxide This interaction with the endogenous documented only when high concentrations Indications for N O opioid system may account in part for abuse (>70%) have been delivered by full mask or 2 14 21 1. For mildly apprehensive patient potential attributed to nitrous oxide. N2O endotracheal tube. These conditions can- also directly