Laughing gas


The chemical name of laughing gas is nitrous oxide, the chemical structural formula is N2O. Laughing gas is a colorless gas and comes from the chemical group of nitrogen oxides. It was synthesized as early as the 17th century, making it one of the oldest anesthetics in the world.

Laughing gas is produced by heating a mixture of ammonium sulfate and sodium nitrate. This is done in the laboratory. However, nitrous oxide can also form in natural surroundings, namely in agriculture. On fertilized arable land or in silos, the corresponding decomposition processes can lead to the formation of nitrous oxide, which in some cases is even sufficient to trigger a corresponding numbing effect (Silonic anesthesia).

What is nitrous oxide sedation?

Laughing gas sedation is the sedation (calming down) of patients, for example to carry out dental treatments. As an inhalation anesthetic, nitrous oxide has a good analgesic effect and only weakly narcotic. Laughing gas is a short-acting narcotic.

With nitrous oxide sedation, the gas is inhaled in combination with pure oxygen. The ratio of nitrous oxide and oxygen is gradually adjusted according to the patient. When the desired calm (sedation) has occurred, the procedure is carried out. During the procedure, the composition of the gas mixture can be adjusted at any time. The patient continues to breathe spontaneously and consciousness is "only" subdued.

During the entire procedure, the patient is monitored using what is known as monitoring. The oxygen saturation is measured and the pulse is determined with a so-called pulse oximeter. In addition, the blood pressure is measured and, if necessary, an EKG is connected. This monitoring is used to control sedation and safety.
After completing the corresponding treatment, the patient breathes in pure oxygen again. This is intended to counteract the effect that the oxygen that is already in the alveoli is diluted by the influx of laughing gas. The resulting oxygen deficiency is prevented by inhaling pure oxygen at the end of the anesthesia. It usually only takes a few minutes until the patient is fully conscious again after the nitrous oxide supply is stopped.

Read more about the topic here: Monitoring during anesthesia.

What is nitrous oxide anesthesia?

The so-called "laughing gas anesthesia" is an anesthetic in which, among other things, laughing gas is used as a short-acting, inhalative narcotic. Since nitrous oxide is good pain reliever, but only has a limited narcotic effect, it is not sufficient as a narcotic alone. In order to achieve a sufficiently deep anesthesia, nitrous oxide is administered with other inhalation anesthetics, e.g. Sevoflurane, analgesics (pain relievers) such as Remifentanil or narcotics to be administered intravenously, such as propofol, combined. Depending on the procedure, muscle relaxants or barbiturates can also be added.

The task of an anesthetist is to provide information about this anesthetic procedure and its implementation. With general anesthesia, nitrous oxide is often added to the gas mixture due to its pain-relieving effect. Thus, the amount of other inhalation anesthetics can be reduced. The effect sets in very quickly and is largely eliminated after a few minutes, since it can be exhaled quickly.

If the combination of nitrous oxide and other drugs is used for general anesthesia / general anesthesia, the same guidelines apply as for general anesthesia without the addition of nitrous oxide. This means that the patient has to be sober. In contrast to sedation, the patient is unconscious under general anesthesia. In addition, ventilation is necessary during the procedure and therefore also the administration of muscle relaxants.

Read more on the subject here General anesthetic.

Indication for nitrous oxide

While laughing gas was used far more frequently in the past, it is only rarely found today and especially during short surgical interventions Use. It has the distinct advantage that it is next to the sedative effect (Unconsciousness) also one analgesic effect (Anesthesia). A combination that not many anesthetics have (mostly just sedating).

If at all, nitrous oxide is now only used for short interventions, as it floods and floods quickly and therefore also acts quickly.

In the Paediatrics Because of its good and well-tolerated effect, it is also often used for small interventions. also in dental procedures also often in children's dentistry.

In the operating room, however, nitrous oxide was largely replaced. Today there are alternative inhalation anesthetics such as Halothane. You will be one longer effectiveness and a better controllability Said during the surgical procedure as well as a more economical use.

Effect of laughing gas

In contrast to many other anesthetics, the effects of nitrous oxide have been relatively well researched today. By inhaling the gas, what is present in the body becomes Vitamin B12 oxidized. Vitamin B12 (Representative of Cobalamin group) is a Coenzyme of the Methionine (Amino acid) production.
By inhibiting vitamin B12, methionine can no longer be formed in the body over a certain period of time, which has the consequence that important Protein building blocks in the body no longer manufactured can be. These protein building blocks also have a supporting role in the Transmission of pain and consciousness.

With the inhibition of vitamin B12, methionine and protein building blocks, awareness and pain perception are reduced, along with other effects. This effect lasts as long as the gas is inhaled. After the gas mixture has stopped, the metabolic processes in the body recover within a few minutes and consciousness and the sensation of pain return.

How does nitrous oxide affect pain?

The exact mechanism of action of laughing gas is not known. One suspects, however, that the effect is based on the inhibition of the exciting messenger substances. Glutamate is particularly important here as a messenger substance for certain receptors. Receptors are a kind of switching point and redirect the signals from messenger substances. Inhibiting these receptors presumably ensures the hypnotic effect of the laughing gas.

Side effect of laughing gas

Laughing gas is a relative Low-side anesthetic agent. For this reason, it has been widely used in the past.

Like any anesthetic, it also has a few Risks and Side Effectswhich are rare but which must be observed. Patients can still have a few hours after using nitrous oxide Drowsiness feel. Driving or responsible activities should therefore not be carried out on the day of the procedure.

Side effects can still occur days afterwards a headache, nausea and Vomit occur. It is also important to clarify in advance of a nitrous oxide treatment whether appropriate Allergies persist against this type of anesthetic. Immediately after using nitrous oxide, it can still be closed dizziness, Drowsiness, but also brief euphoria.

At Overdose of the gas mixture can lead to long-lasting neurological symptoms, such as neurological failures, Paralysis, Speech disorders, Gait disorders come. There is practically no overdose in medicine. The danger of an overdose is to be found above all in the drug sector, where nitrous oxide is inhaled in high doses because of its sedating and sometimes intoxicating effects. In the case of a systematic and regular overdose, irreparable damage, such as undersupply of the brain with permanent neurological damage, has also been observed.

Use of nitrous oxide

The application is as follows: the patient will get one Mask with emitted nitrous oxide held in front of the face and asked to breathe in normally. Then the mask is placed directly on the nose. The effect puts in a few seconds and puts the patient in one Deep sleep.

Another benefit of laughing gas is that gaseous availability. In an emergency, it is not absolutely necessary to provide venous access (but recommended for safety reasons).

Nitrous oxide during childbirth

The use of nitrous oxide is not that common during childbirth, but it is also sometimes used. Here laughing gas is used less for sedation than for Fight pain the labor pains. Since 2008 a nitrous oxide-oxygen mixture has been used in Germany for birth Painkiller authorized. In countries like Scandinavia or England, this preparation has been on the market for a long time.

For the sole pain relief during childbirth, a gas mixture of 50% nitrous oxide with 50% oxygen necessary. It is important that the gas mixture is inhaled before each contraction in order to dampen a corresponding pain attack.

Nitrous oxide mixtures are mainly used in obstetrics when there are objections and contraindications to other pain methods. Today, however, the pain relief in obstetrics has Epidural anesthesia (PDA) enforced.

If you want a less invasive pain treatment, you can also give the woman giving birth painkillers in the form of an infusion. Medicines such as: Pethitin (Dolantin®) to use.

Laughing gas at the dentist

Laughing gas is probably used most frequently today in the Dentistry. Especially in the Pediatric Dentistry Laughing gas is very popular and is often used. While in adults a local anesthetic is often injected into the gum area, in children another method of anesthesia has to be found. Laughing gas has the decisive advantage that it can be given to the patient directly via a nebuliser through a mask.

During dental interventions, e.g. in the Tooth filling or that pull teeth it is often enough to give to the child Nitrous oxide-oxygen mixture to hold in front of your nose. The child inhales the gas and, on the one hand, becomes calmer, and on the other hand, the pain sensation is reduced.

In dentistry, deep sleep anesthesia is often not necessary at all. After the procedure, the gas is turned off and the little patient can immediately discharged without further observation become. Shortly after the gas has been drained off, however, it can still close nausea, light dizziness and a headache come. These side effects are relatively rare and usually only last a few hours.

For safety reasons, however, it is regulated in Germany that dental practices that perform operations under nitrous oxide must have an anesthetist in the practice. These anesthesiologists are often freelance and not employed in a hospital and drive from dental practice to dental practice.