Nitrous Oxide in the ED

The devices are made with abuse potential in mind. For example the mobile unit has to be plugged into wall oxygen and wall suction. Which is very difficult to accomplish outside of an active clinical area. Additionally the breathing masks have to be pulled out of the omni cell in order to make the device work. We also keep the device in our trauma bay which is under 24 hour video surveillance. So you need to get a breathing circuit from a nurse from the omi cell, get the device from the video monitored trauma bay, plug into wall oxygen and then wall suction which is loud. These steps make abuse very difficult. Previous to these devices abuse was much easier. But now it’s Extremely difficult.

Below is the protocol we use at our hospital via Dr. LaPietra:
Background
Nitrous Oxide (N2O) is a tasteless colorless gas administered in combination with oxygen via inhalation as an analgesic and sedative agent. N2O is rapidly absorbed via the pulmonary vasculature into the bloodstream, and does not combine with hemoglobin or other body tissues. N2O rapidly reaches the central nervous system within minutes. Administration of N2O can achieve similar analgesia as compared to opioid analgesia, with the added benefit of noninvasive administration, and the ability to titrate up and down to achieve rapid onset and elimination. It has an impeccable safety record with few side effects and requires only minimal monitoring during use.
Indications (Ages 1 year and older)
Reduction of joint dislocations
Adjunct to other analgesia in fracture reduction
Splinting
Adjunct to local anesthetic for laceration repair
Adjunct to local anesthetic for incision and drainage of soft tissue/bartholin’s abscesses
Advanced wound or burn care
Foreign body removal
Adjunct to local anesthetic for Central Venous Access
Peripheral Venous Access
Adjunct to local anesthetic for Lumbar Puncture
Fecal Disimpaction
Cardioversion
Contraindications
Nitrous oxide has 15 times higher solubility ratio as compared to nitrogen, and in high doses can cause gaseous expansion in enclosed air spaces. Additionally, in patients who breathe via a hypoxemic drive secondary to lung disease may have respiratory compromise with the administration of high concentrations of N2O.
Complete obstruction of nasal passages (severe acute bacterial sinusitis)
Severe COPD
1st and 2nd trimester pregnancy
Severe asthma
Altered level of comprehension secondary to psychiatric disease, intoxication, or head injury
Complex advanced cardiac disease
High suspicion of otitis media, bowel obstruction, or pneumothorax

Maintenance/Servicing/Storage
Nitrous oxide will be stored in the ED and maintained by Medical Director of EM Pain Management, respiratory therapy will provide new nitrous tanks . Apply a face mask suitable for the patient’s face size; sizes include small, medium, and large. Position patient as needed for procedure or analgesia.
Administration
N2O will be administered by licensed independent provider.
N2O is administered along with oxygen at varying levels of concentration. The maximum safe concentration is a 70% N2O: 30% mixture oxygen. Titration of the mixture should start at 10% N2O: 90% oxygen. The optimal concentration of nitrous oxide to achieve desired analgesia or sedation will vary with each patient, and can vary in the same patient presenting with different pain or sedation needs. The operator can assess when the correct level of analgesia is met by using a verbal pain scale or when the patient no longer adversely responses to the painful stimuli but is still able to communicate. The correct level of sedation can be assessed when the patient appears sedated, has minimal to no response to painful stimuli, but is able to communicate without significant stimulation.
Special Considerations in pediatrics- there is an increase rate of emesis in younger children post- administration. The risk increases with younger age, increased concentration, and increased duration of administration. For complicated lengthy (>30 minutes) procedures prophylactic treatment with an anti-emetic is recommended.
Set the mixture dial to 100% oxygen and allow the patient to breathe through their nose for one minute
Turn the mixture dial to 70% oxygen (30% nitrous oxide) and allow patient to breathe through their nose for approximately one minute
Turn the mixture dial to 50% oxygen (50% nitrous oxide) and allow patient to breathe through their nose for approximately one minute
Continue to titrate oxygen level down (allowing the nitrous oxide concentration to rise) until desired level of analgesia or sedation is achieved. Be aware that the mixture will not go below 30% oxygen or 70% nitrous oxide
Continue administration of gas at the desired concentration throughout procedure or as needed for analgesia. If at any point the patient becomes over-sedated titrate oxygen concentration back up. The operator may continue to titrate the gas mixture up and down as needed. The effects of changing the nitrous oxide concentration should be apparent within one to two minutes.
Once the procedure is completed or the patient’s analgesic needs have been met the operator should turn the dial back down to 100% oxygen and allow the patient to breathe through their nose for 2-5 minutes before removing the face mask.
Allow the patient to remain in a chair or the bed for an additional 2-5 minutes while breathing room air before safely discharging.
Patients will not require any restriction on activity or driving if only nitrous oxide was administered.
Monitoring
Vital signs – pre administration, 2 times every hour and post administration.
O2 saturation via pulse oximetry during administration
Level of consciousness to be monitored via direct observation by provider
Discharge Criteria:

Vital signs should be checked prior to discharge,
Patient must maintain or achieve a return of their baseline vital signs and mental status prior to discharge.

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