Introduction
Vomiting after an anesthesia is a side effect of anesthesia, which is feared by many patients. In medical terminology, it is also referred to as post operative nausea and vomiting, or PONV for short. Without prophylaxis, up to 30% of patients suffer from nausea and vomiting after general anesthesia, so that it is a relatively common side effect.
Ultimately, every 3rd patient is affected by nausea and vomiting after surgery. There are several factors that can cause this. These include drug properties, but age and gender also play a role.
Younger people as well as women are affected significantly more often than the rest of the population. However, not all mechanisms of development are fully understood. Anaesthesia in older people
Duration
Vomiting after anesthesia usually begins immediately after the procedure or when the patient wakes up. However, the duration and severity of the nausea and vomiting vary greatly and depend on various factors. Certain drugs, e.g. opioids and inhalation narcotics, carry a higher risk of vomiting after anesthesia than other drugs.
However, the anaesthetist will inform the patient about this individually before the operation. Furthermore, vomiting also depends on individual factors of the patient, so that it is very difficult to estimate the duration. As a rule, good prophylaxis is carried out by the doctors, but vomiting can still occur after the anaesthetic.
Usually it lasts up to 24 hours with interruptions. The probability of recurrence of vomiting is still high within 35 hours after the procedure. In order to break through the duration of this period, it is advisable to take early action against vomiting with a drug therapy. Most often combinations of several drugs are used.
Causes
The origin and all causes of vomiting after anesthesia are not yet conclusively clarified at the present time of research. However, there are some risk factors that appear to be certain. A distinction is made between patient-related and anaesthesia-related risk factors.
A higher risk possess women and younger humans opposite the remaining population. Also humans seem to be concerned more frequently, who suffered in their life already from travel sickness. Further smokers are by far more rarely concerned than nonsmokers.
After one has already suffered from vomiting after anesthesia in the past, the risk of suffering from it again after an operation increases. Certain aspects of anesthesia also represent risk factors for vomiting after anesthesia. Ultimately, however, the exact causes are not clear.
So-called volatile anesthetics seem to cause an increased risk. These are anaesthetics that are inhaled. The administration of opioids after or during surgery also seems to increase the risk of vomiting after anesthesia.
The type of surgery seems to have an influence, but this factor is not certain. The vomiting itself is caused by special receptors in the brain to which messenger substances such as serotonin or dopamine bind. It is a complicated process, which is caused by the interaction of different structures of the esophagus, the vestibular system and the nervous system.
However, it is not clear why vomiting and nausea occur, especially after anaesthesia. Opioid analgesics are administered under almost every anaesthetic to provide sufficient freedom from pain. One of the most common side effects after taking opioids is nausea and vomiting.
This is due to the special effect of opioid drugs in the brain. Among other things, opioids stimulate dopamine-dependent receptors in the area postrema, which stimulates the vomiting center in the reticular format and leads to nausea and vomiting. If a tendency to postoperative nausea is known, or if there are many risk factors for the occurrence of postoperative nausea, antiemetic drugs (for nausea and vomiting) can be administered for prophylaxis immediately after induction of anesthesia.
All articles in this series:
