Nitrous oxide RDA
Indications for Nitrous Oxide
1. Anxious patient 2. Increased gag reflex 3. Traumatic dental procedures 4. Sickle cell trait-anemia 5. Bleeding disorders 6. Physical handicap 7. Epilepsy 8. Pregnancy (not first trimester) 9. Cardiac disorders 10. Mentally handicapped
Contraindications for Nitrous Oxide
1. Common cold 2. Tonsillar/adenoidal hyperplasia 3. Serious pulmonary disease 4. Psychiatrically treated patient 5. Multiple sclerosis 6. Myasthenia gravis
Three general factors that may produce dyspnea:
1.The patient's state of mind .2.Increased work of respiration .3.Abnormalities in the oxygen and carbon saturation
Normal blood pressure
120 mm Hg - Systolic Pressure 80 mm Hg - Diastolic Pressure
rule of thumb for reading nitrous gauge
2.5 units of oxygen are utilized to every 1 unit of nitrous oxide unit
Stages of Anesthesia: Stage 4
Death
Oversedation - - Management
Decrease the concentration of nitrous oxide in increments of 10-20*
Bradycardia
Decreased Heart Rate or slowness of a heart beat Less than 60/min
Rule 108.31108.3
Delegation of the monitoring of the nitrous oxide/oxygen monitoring inhalation conscious sedation procedure to a dental auxiliary who has been certified to monitor the been certified
Most Common Cause of Hypoxia
During inhalation conscious sedation is inadequate oxygenation - ventilation
Larynx
Epiglottis and Vocal cords
Alteration of Psychological and Physical State
Euphoria and Excitation Floating and Delusions Numbness and Tingling Review other in text
Minor Complications:
Excessive perspiration Increased expectoration Shivering Paresthesia Numbness Tingling in extremities "Light-headed" Fear Hyperventilation
Stages of Anesthesia: Stage 2
Excitement Loss of consciousness, disappearance of Eyelid reflex, irregular respiration, irregular respiration, agitation, dilated pupils
Advantages of Inhalation Conscious Sedation
Few Side Effects Rapid Onset Peak Clinical Effect Quick Increase Decrease effect Variable Duration Rapid Recovery Analgesia Agent Non-invasive Procedure Administered In-Office
Diffusion Hypoxia
Hypoxia is an inadequate oxygen concentration necessary for cellular respiration and function.
Signs of Patient Over sedation
Inability to Keep Mouth Open Agitation Failure to Respond to Verbal Commands or Stimulation Slurred / Incoherent Speech Uncooperative Increased Excitability Uncoordinated Muscular Movement Nausea
Tachycardia
Increased Cardiac Output or rapid beating of the heart Greater than 110/min
YOU SHALL NOT
Induce or start nitrous oxide-oxygen on any patient Increase the concentration of nitrous oxide for any reason
Oxygen Flush
It is activated by pressing a button which opens the oxygen flow directly from the line bypassing the flowmeter utilized to get a large volume of oxygen to the reservoir bag or patient quickly.
Precautions for tank storage
Keep oil or grease from coming in contact with the high pressure gas When gas flows from the tank at high pressure, a rapid increase in temperature may result. not flammable but they will support combustion vertical position restrained against a wall
Direct Supervision
Level of supervision in which the dentist is physically present when the dental auxiliary performs delegated functions
ONLY the Dentist
May induce and administer the sedation medication (nitrous sedation medication (nitrous oxide-oxygen).oxide-oxygen
Plane 1
Moderate Analgesia Utilization of N2O of between 5-25%
Patient monitoring-Post treatment
Monitor for hypoxia/respiratory status
Nitrous Oxide Concentrations
Most dental analgesia obtained 25-50% O2 concentration never below 30%
Certification for Monitoring
Must be currently certified in basic cardiac life support Must pass a written certification examination pass a written certification examination prepared and administered by a TSBDE
Major Complications:
Nausea Vomiting Regurgitation Pulmonary Aspiration Tachycardia Tachypnea Cyanosis Hypoxia Bradycardia
Basic Pharmacology Facts
Nitrous oxide diffused readily to and from the blood and body tissues. It does not change its form the majority of the gas is exhaled from the body within 3 - 5 minutes after its termination.
Physical Properties Nitrous oxide
Nitrous oxideis a colorless, odorless , tasteless, non-irritating gas with central nervous system depressant ability
Respiratory Rate
Normal 12-20 beats/min Exceed 35/min - hypoxia
Pulse
Normal adult 60-72
Diastolic Pressure
Pressure is controlled by the compliance or resistance of the vascular system
Systolic Pressure
Pressure that is created by the left ventricular contraction and may be influenced by vascular factors
Anesthesia
Preventing the brain from receiving painful stimuli
Reservoir Bag
Rubber or sillicone range from sizes 1-8 3 liter size is commonly used with adults while a pediatric bag of 1 liter used for child
Nasal Hood or Mask
The most commonly used apparatus in the dental office .The hood only covers the nose
Pharynx
The pharynx is divided anatomically into three areas: areas: nasopharynx ,oropharynx and laryngopharynx
Correct Cuff Size
The size of the pressure cuff utilized must be appropriate for the patient's arm. A cuff smaller than indicated will produce a high aberration (deviation from the normal) in the blood pressure while a larger cuff will do the opposite.
Plane 2
The utilization of nitrous oxide concentration of between 25-55%
Induction Phase
This phase begins as the dentist first turns the dials of the nitrous oxide oxygen machine and places the nasal mask on the patient
Maintenance Phase
This phase begins when the desired level of sedation is obtained, continues for the indicated duration of the procedure
Recovery Phase
This phase begins when the nitrous oxide is turned to the "off" position continues during the oxygen administration, and ends when the patient is in total control of their well being
Plane 3
Total Analgesia The utilization of a nitrous oxide concentration of between 55-70% Patients may experience amnesia and even lose consciousness
Patient Monitoring-Pre-Treatment
Visual and auditory observation most important aspect vital signs checked every every 15 minutes A current history and limited physical evaluation on all dental patients should be performed.
Monitoring Objective Symptoms
What Can be observed Consciousness Relaxation Normal Vital Signs Decreased eye lid blink Reflexes Intact Responds to Verbal Command Decreased Response to Painful Decreased Movement
Monitoring Subjective Symptoms
What the patient is feeling Paresthesia or tingling Mental and Physical Relaxation Psychic and Somatic Sedation Altered Pain Threshold Lethargy Euphoria Dreaming Feeling of Warmth Sense of Detachment
continuous flow types
a continuous, constant flow of gases is delivered to the patient gases is delivered to the patient even on exhalation
Nitrous oxide is stored
as a gas and about 30% liquid As the gas is used, the liquid is converted to more gas
nasopharynx
begins at the posterior opening of the nose, and extends to the superior opening of the nose, and extends to the superior portion of the soft palate.
oropharynx
begins at the soft palate and extends to the level of hyoid bone in the neck. contains the tonsillar lymphatic tissue bilaterally
complete face mask
best use of the face mask is in the event of an emergency
Nitrous oxide
blue
Sir Humphrey Davy
described the analgesic-euphoric properties of the analgesic-euphoric properties of nitrous oxidenitrous oxide and later named it and later named it "laughing gas.1978
Joseph Priestley
discovered nitrous oxide in 1773
Purpose of the reservoir bag
even gas flow which prevents wide swings in gas concentrations helpful as a respiratory monitoring device may also be used as a means to assist or control respiration in the event of an emergency.
laryngopharynx
extends from the hyoid bone to the beginning of the esophagus
Horace Wells
first to recognize the medical application of recognize the medical application of nitrous oxidenitrous oxide. 1842
Portable System
gas cylinders combined into one single unit ,movable from one operatory to another
Oxygen is stored
gas under pressure between 2000 - 2200 psi
Oxygen
green
Weak / Thready Pulse
indicative of a decrease in the stroke volume as seen in hypo tension, syncope, cardiac failure, or shock
Central Storage System
larger gas cylinders (G or H cylinders) are stored in a dedicated area away from the operatory, the cylinders are connected to the operatory by copper tubing
Gas Flow Measured in
liters /minute
Direct hypoxia
may occur due to the dilution of oxygen. subsequent hypoventilation and indirect hypoxia will occur
Flowmeter
measures the quantity of the gas delivered
Oxygen Fail Safe
mechanism which shuts off or prevents the initiation of nitrous oxide delivery without oxygen flowing
Patient monitoring- Treatment phase
mental status cardiovascular status respiratory status skin color
Personal Supervision
physically present in the physically present in the room with the patient at all times room with the patient at all times during the induction and during the induction and maintenance of the procedure
Internal Nose
posterior openings into the nasal pharynx are called the choanae. Any blockage would potentially alter the amount of sedation agent getting to the patient
Transport or Conduction system
provides for the transport of air (oxygen and other gases) from outside of the body to the respiratory area of the lungs and transport of waste gases (carbon dioxide)to the outside.
Cyanosis
the bluish color noted in the skin as a result of excessive unoxygenated hemoglobin in the blood. a late symptom of tissue hypoxia. tissue Treat the problem with 100% oxygen
Prevention:
Administer 100% oxygen for 3-5 minutes after termination of N2O
Staff Safety
Air mixing utilized by placing a fan in the operatory levels drop to 14 ppm (parts per million).
What activates vomiting?
Cortical (Brain) Stimulus stress, fear, depression, smell, taste, visual, pain, fear, depression,pain, migraine headaches, increased intracranial pressure, and hypoxia
Dyspnea "short of breath."
An awareness of increased difficulty breathing due to a disproportion between the perceived demand for disproportion ventilation and that achieved
Hypoxia
An inadequate oxygen concentration necessary n necessary for cellular respiration and function.
Stages of Anesthesia: Stage 1
Analgesia begins at the induction of the sedation or general anesthesia procedure and ends with the loss of consciousness
Heart Rate
Average adult rate: 60-80/min
Rule 109.171
Chapter 108, , Subchapter C, in February 2001 allow delegation of patient monitoring during the inhalation sedation procedure under certain conditions.
Nitrous Oxide Safety Considerations
Scavenging Hood Air Mixing Disposable Nasal Hood Testing of N2O Equipment Proper Venting of Gases Monitoring of N2O concentrations
Cortical Stimulation
Secondary to hypoxia and the leading cause of nausea and vomiting during nitrous oxide conscious sedation procedures
Stages of Anesthesia: Stage 3
Surgical
Combined System
Systems that unite the central gas cylinder storage and the portability of cylinder storage and the portability of machine movement among the operatories wall outlets are referred to as a combined system
Hypertensive Readings
Systolic> 160 mm Diastolic> 115 mm Pulse> 90-104 bpm
Pulmonary Aspiration
The aspiration of gastric contents or other fluids or solids into the pulmonary bronchial system
Analgesia
The diminution elimination of pain.pain
Analgesia
The diminution or production of increased tolerance to pain in the conscious patient.