Cause 

After surgical interventions – more accurately: following the anesthesiologic procedures used – nausea and vomiting (PONV) are among the most common complications. Supposedly, one in three patients is affected.

In the medulla oblongata (a part of the central nervous system between the brain and the spinal cord) the vomiting center is located; it can be stimulated by various substances.

Risk factors for PONV include female gender, PONV is more common in younger people and smokers are less often affected than non-smokers. Patients who suffer from travel sickness also have a higher risk of PONV.

Among the medications used in anesthesiology, inhalation anesthetics and opioids are associated with an increased PONV risk.

There are various scoring systems that can be used to assess PONV risk. However, it is now recommended to use PONV prophylaxis on all patients. This includes avoidance of inhalation anesthetics, good hydration and also the use of strong antiemetics.

Symptoms

Affected patients suffer from nausea and vomiting to an extent that markedly reduces their wellbeing. This is associated with a risk of aspiration of vomit, especially right after anesthesia when protecting reflexes have not fully returned. Furthermore, vomiting can cause electrolyte imbalances.

Diagnosis

In order to assess PONV risk, the Apfel score can be used. It contains four items: female sex, history of PONV or travel sickness, non-smoking and postoperative use of opioids. One point is awarded for each item. At 0 points, the PONV risk is 10%, at four points it is 80%. From three points onwards, the PONV risk is regarded as high.

Other systems, like the Koivuranta score, can be used as well.

Treatment Guidelines 

In the sign-in area, specialists can find a current guideline on prophylaxis and management of PONV at:

https://pubmed.ncbi.nlm.nih.gov/32467512/