Sedation Relative analgesia (RA)
Relative analgesia (RA) is the medical term for what patients know as gas and air.
RA is an inhalation sedation technique, which is administered by placing a small hood over the nose only. This delivers the Oxygen and Nitrous Oxide (laughing gas), which the patient inhales in a normal breathing rhythm up and down their nose.
This produces, after a short time, pleasant tingly feelings in hands and feet which then progresses to equally pleasant feelings of warmth, wellbeing and euphoria and reduced anxiety levels. A feeling of slightly floating sensations is experienced.
RA is suitable for almost anyone young or old. We commonly use it on our child patients for treatment which sometimes removes the need for injections or if we do need local anaesthetic it means this can be administered when the patient is “floating” and does not even know an injection is being given. We use this same technique on adults who are anxious or frightened of having dental treatment. It also works very well for patients who have a strong ‘Gag reflex’ reducing this down to much less sensitive levels. Patients who have a tendency to claustrophobia or panic attacks also find RA reduces all these anxieties.
RA is VERY safe as the patient is wide-awake and so still in control albeit a little ‘floaty’ and happy!
The patient does not need to starve prior to their visit but we would recommend only light eating and drinking beforehand.
Advantages of nitrous oxide
- RA works very rapidly – it reaches the brain within 20 seconds, relaxation and pain-killing properties develop after 2 or 3 minutes.
- The depth of sedation can be altered from moment to moment, allowing the dentist who administers the gas to increase or decrease the depth of sedation. Other sedation techniques don’t allow for this. For example, with IV sedation, it’s easy to deepen the level of sedation, but difficult to lessen it. Whereas with “The Magic Carpet Ride”, the effects are almost instant.
- Other sedation techniques have a fixed duration of action (because the effects of pills or intravenous drugs last for a specific time span), whereas RA can be given for the exact time span it’s needed for.
- There’s no “hangover” effect – the gas is eliminated from the body within 3 to 5 minutes after the gas supply is stopped. You can safely drive home after a few minutes sat in the waiting room before you leave and don’t need an escort.
- With nitrous oxide, it’s easy to give incremental doses until the desired action is obtained (this is called “titration”). So the administrator has virtually absolute control over the action of the drug, preventing the possibility of accidental overdoses. While giving incremental doses is possible with IV sedation, it’s not possible with oral sedation.
- For certain procedures it may be possible to use RA instead of local anaesthesia.
- In cases of needle phobia, the “Magic Carpet Ride’ first helps you feel relaxed enough to allow the local anaesthetic to be administered with no issues.
- Inhalation sedation is very safe. It has very few side effects and have no ill effects on the heart, lungs, liver, kidneys, or brain.
- Inhalation sedation has been found to be very effective in eliminating or at least minimizing severe gagging and for patients with claustrophobia or anxiety attacks.
- It allows the patient to access dental treatment that they may well not be able to tolerate without RA.
- It allows high quality dental work to be carried out because everyone is relaxed (patient and therefore the dental staff) and so doing good work is so much easier.
Are there any disadvantages?
- Some people are not comfortable with the effects of RA (either because they’re afraid they might lose control or because it makes them feel nauseous – this is quite rare, though.). If you’re prone to nausea, it’s a good idea to have a meal (not a huge one) about 4 hours before your appointment. If that’s not possible (e. g. an early morning appointment), make sure your stomach isn’t completely empty – but don’t over eat beforehand either.
- If you can’t breathe through your nose, either because you’re a pure mouth breather or because your nose is blocked.
Are there any contraindications?
- There aren’t any major contraindications to relative analgesia, except for M.S., emphysema and some chest problems. It hasn’t been proven to be safe during pregnancy, so you can’t use it then.
- Because you have to breathe it in through your nose, it’s not suitable for people who have a cold or some other condition, which prevents them from breathing through their nose.
- You can’t be allergic to Nitrous Oxide. It’s also safe to use if you suffer from epilepsy, liver disease, heart disease, diabetes, asthma or cerebrovascular disease. It is also used quite successfully in many people with respiratory disease – but it depends on the exact nature of the disease, so check with your dentist!
- If you have a latex allergy the nasal hood could cause a reaction so best to avoid.