Post-operative nausea and vomiting (PONV): definition, risk factors and treatment
Post-operative nausea and vomiting (PONV) occurs within the first 24 hours following surgery under general anaesthesia and affects around 30 % of all patients.
Post-operative nausea and vomiting (PONV):
Post-operative nausea refers to nausea, retching or vomiting that occurs within the first 24 hours following a surgical procedure under general anaesthesia. PONV affects around 30 % of all patients following general anaesthesia and is one of the most common complications in the recovery room.
Table of Contents
Important note
This article is for information purposes only and is not a substitute for a medical diagnosis or advice. If you are unsure, or if you require a personalised treatment plan, it is essential that you consult a qualified specialist.
Post-operative nausea is one of the complications about which patients are rarely given sufficient information prior to surgery. Yet, statistically, it affects one in three people following general anaesthesia, and the figure is significantly higher for certain procedures, such as gynaecological or abdominal surgery. Anyone planning cosmetic surgery should be aware of the causes, risk factors and possible consequences so that they are well prepared.
How common is PONV?
- Around 30 % of all patients following general anaesthesia are affected
- For high-risk groups, the rate rises to 70–80 %
- Alongside pain, PONV is one of the most commonly reported symptoms following surgery
- Without targeted preventive measures, the incidence for certain procedures is over 60 %
Post-operative nausea and vomiting, medically referred to as PONV (Post-operative Nausea and Vomiting), are among the most common adverse events following surgical procedures. According to data from the medical literature, PONV affects on average 30 % of all patients undergoing surgery under general anaesthesia. In individuals with multiple risk factors, this rate rises to 70–80 %.
Incidence of PONV according to the Apfel score: The likelihood of post-operative nausea increases significantly with each additional risk factor.
PONV is particularly relevant in the case of procedures that are frequently carried out in a cosmetic context: According to clinical studies, laparoscopic surgery (e.g. in the abdominal region), gynaecological procedures and abdominal surgical procedures such as abdominoplasty are considered high-risk procedures for PONV. Without targeted preventive measures, the incidence of PONV in these procedures can exceed 60 %.
The economic impact is significant: studies show that PONV, on average, prolongs the stay in the recovery room and, in some cases, may necessitate unplanned admission to hospital. For patients who had planned to undergo cosmetic surgery on an outpatient basis, this means additional costs that they must bear themselves, as statutory health insurance does not cover cosmetic surgery.
What causes post-operative nausea?
Key points at a glance:
- The vomiting centre in the medulla oblongata processes stimuli from several sources simultaneously
- Inhalation anaesthetics, nitrous oxide and opioids are the most potent pharmacological triggers
- General anaesthesia causes significantly more PONV than regional anaesthesia or TIVA
- Operational factors such as the duration of the procedure and the area of the body also influence the risk
Post-operative nausea arises from a complex interplay of neural and pharmacological processes. A key factor in this is the Emergency Centre, a region in the medulla oblongata of the brainstem that receives and coordinates signals from various sources. These signals originate from the gastrointestinal tract, the vestibular system and the chemoreceptor trigger zone (CTZ), which is located in the area postrema of the brainstem.
The CTZ is particularly sensitive to chemical substances in the blood. Anaesthetics, in particular Inhalation anaesthetics Such as isoflurane or sevoflurane, as well as nitrous oxide, directly stimulate the CTZ. The same applies to opioids (e.g. morphine or fentanyl), which are frequently used for post-operative pain management. This is why PONV remains an issue even long after the operation itself has finished.
An overview of three categories of causes
Medical societies distinguish between three main categories of triggers that contribute to PONV:
Patient-related factors
Female gender; non-smoker status; history of PONV or travel sickness; younger age; pre-operative anxiety
Anaesthesia-related factors
Inhalation anaesthetics (sevoflurane, isoflurane); nitrous oxide; intraoperative and postoperative opioids; prolonged duration of anaesthesia
Operational factors
Laparoscopic procedures; gynaecological operations; abdominal surgery; ENT operations; procedures near the vestibular system
It is important to understand that PONV is not a sign that the anaesthesia has been administered incorrectly. It is a biologically based reaction that can occur despite the most careful preparation. For patients planning cosmetic procedures under general anaesthesia, such as liposuction, this is a relevant factor to consider when weighing up the risks.
Risk factors and risk assessment: the Apfel score and the Koivuranta score
Key points at a glance:
- The Apple Score is the most widely used tool for assessing the risk of PONV in adults
- It comprises four factors; even two of these factors indicate a risk of 40 %
- The Koivuranta Score expands the assessment to five factors
- Both scores serve as a basis for anaesthetists when deciding on prophylaxis
Anaesthetists use standardised scoring systems to systematically assess an individual’s risk of PONV. The best-known of these is the Apple Score, which assesses four clearly defined factors.
Apple Score: The four risk factors
| Risk factor | Explanation |
|---|---|
| Female gender | Due to hormonal factors, women are affected significantly more often than men |
| Non-smoker status | Smoking appears to have a certain protective effect; the exact mechanism is not yet fully understood |
| A history of PONV or travel sickness | Anyone who has experienced nausea following anaesthesia in the past or who is prone to travel sickness is at increased risk |
| Post-operative opioid administration | Opioid painkillers (e.g. morphine) increase the risk of PONV following surgery |
Apple Score: Probability per number of factors
| Number of risk factors | Probability of PONV | At-risk group |
|---|---|---|
| 0 | approx. 10 % | Low risk |
| 1 | approx. 20 % | Low risk |
| 2 | approx. 40 % | Medium risk |
| 3 | approx. 60–70 % | High risk |
| 4 | approx. 80 % | Very high risk |
For female patients planning cosmetic surgery under general anaesthesia: according to the Apfel Score, being female and a non-smoker combined already results in a moderate risk of around 40 %. Added to this are surgical factors such as the type of procedure. This highlights how important it is to carry out a risk assessment before the procedure.
The Koivuranta Score: A supplementary tool
The Koivuranta Score adds a fifth factor to the Apple Score: procedures lasting more than 60 minutes. Many cosmetic procedures, including extensive liposuction or combined operations, exceed this threshold. The Koivuranta system is therefore particularly useful for pre-operative planning in the field of aesthetic surgery. Both scores achieve an accuracy of around 70 %; they should therefore be regarded as a guide rather than an absolute prediction.
Information for patients:
Before the operation, please tell your doctor if you have suffered from nausea following anaesthesia in the past or if you are prone to travel sickness. This information is crucial in deciding on the appropriate preventative treatment.
Prevention: How to prevent post-operative nausea
- Pharmacological prophylaxis with 5-HT3 antagonists (e.g. ondansetron) and dexamethasone is considered the standard of care
- For high-risk patients, the DGAI recommends dual prophylaxis using two different classes of active substances
- TIVA (total intravenous anaesthesia) with propofol significantly reduces the risk of PONV compared with inhalation anaesthetics
- Non-pharmacological measures such as acupressure complement pharmacological prophylaxis
The prevention of post-operative nausea begins even before the incision is made. Anaesthetists assess the individual risk and adjust the anaesthesia management and accompanying medication accordingly. According to the guidelines issued by the Scientific Working Group on Paediatric Anaesthesia of the DGAI (German Society for Anaesthesiology and Intensive Care Medicine, 2023), high-risk patients should receive Dual prophylaxis The standard approach involves two different classes of antiemetic active substances.
Pharmacological prophylaxis: the main classes of active substances
5-HT3 antagonists Like ondansetron and granisetron, they block serotonin receptors in the chemoreceptor trigger zone. They are regarded as the most effective single class of drugs for treating PONV and are routinely used in many hospitals. Dexamethasone, a corticosteroid, complements the treatment well and, when used in combination with a 5-HT3 antagonist, is significantly more effective than either drug on its own. Droperidol, a dopamine antagonist, is also used, but less frequently than in the past, due to the need for cardiac monitoring.
Metoclopramide, known to many as a home remedy for nausea, is now rarely used in perioperative prophylaxis, as it is less effective than the newer 5-HT3 antagonists.
Basic anaesthetic measures to reduce PONV
In addition to medication, there are anaesthetic strategies that structurally reduce the risk of PONV:
- TIVA (Total Intravenous Anaesthesia) with propofol Unlike inhalation anaesthetics, propofol itself has mild antiemetic properties
- Avoid nitrous oxide (N₂O), one of the most potent triggers of PONV
- Keep intraoperative and postoperative opioid use to a minimum; favour multimodal pain management
- Adequate fluid intake before and during the operation
- Give preference to regional anaesthesia wherever medically feasible
Non-medicinal alternatives: acupressure and ginger
Acupressure on the Point P6 (Nei-Kuan point on the wrist) has been shown in several clinical trials to be moderately effective in reducing post-operative nausea. Special acupressure bands can provide continuous stimulation of this point. The effect is weaker than that of pharmacological prophylaxis, but there are no side effects. Ginger extract is also under consideration; the available evidence is not yet conclusive enough to warrant a clear recommendation, but the risk profile is favourable. Both methods are suitable as a supplement to pharmacological prophylaxis, but do not replace it in high-risk patients.
Treatment: Management of PONV once it has occurred
- If PONV occurs, antiemetics from a different class of active substances to those used for prophylaxis are administered
- Ondansetron is the most commonly used rescue medication in the recovery room
- Non-pharmacological measures support recovery
- If vomiting persists for more than 24 hours, it is essential to seek medical advice
If PONV occurs despite prophylaxis, specific treatment begins in the Recovery room (PACU, Post-Anaesthetic Care Unit). As a general rule, if a 5-HT3 antagonist has already been used for prophylaxis, a substance from a different class of active ingredients should be used for treatment in order to achieve an additive effect.
Medication in the recovery room
Ondansetron (a 5-HT3 antagonist) is the most commonly used rescue medication. It acts quickly and has a favourable side-effect profile. Alternatively, dexamethasone, dimenhydrinate or, in severe cases, droperidol may be used. The choice depends on which substances have already been administered for prophylaxis. Metoclopramide can be used as a supplementary option, but is less effective.
Non-pharmacological supportive measures
As well as medication, simple measures can help to relieve the symptoms. Fresh air or a cool flannel on the face can help to reduce the urge to vomit. Sitting up slowly rather than standing up abruptly prevents dizziness from making the nausea worse. Clear fluids in small amounts help to prevent dehydration, provided the vomiting has subsided. Solid food should not be eaten until the nausea has significantly eased.
If vomiting persists for several hours or occurs more than three times within 24 hours, medical advice should be sought. Severe vomiting can lead to dehydration and electrolyte imbalances, which, in rare cases, may require medical treatment.
Complications: When does post-operative nausea become dangerous?
- Aspiration of gastric contents is the most serious medical complication (Mendelson’s syndrome)
- Severe retching can compromise surgical stitches and delay healing
- Dehydration caused by persistent vomiting requires medical attention
- Longer recovery times and unplanned hospital admissions increase treatment costs
Post-operative nausea is unpleasant for most patients, but it is temporary. In a minority of cases, however, PONV can lead to serious consequences.
Medical complications caused by PONV
The most dangerous complication is the Aspiration: If stomach contents enter the airways during vomiting, this can trigger chemical pneumonia, which is known as Mendelson syndrome is well known. This risk is the main reason why patients must fast for several hours before surgery. Persistent retching can also put pressure on freshly sutured wounds; this is a particularly relevant factor following abdominal surgery or a breast lift. Wound dehiscence – that is, the tearing open of sutured wounds – is a possible consequence.
Dehydration and electrolyte imbalance occur during prolonged vomiting, when the body loses too much fluid and minerals. In severe cases, intravenous fluid replacement is necessary.
Economic consequences: Who bears the costs?
PONV also has a financial aspect that is often underestimated. A prolonged stay in the recovery room ties up nursing staff and resources. If patients have to be admitted as inpatients unexpectedly following a cosmetic procedure originally planned as an outpatient procedure, this results in additional costs. In the case of privately funded cosmetic surgery, these costs are not covered by health insurance but are borne by the patient themselves.
This is precisely where the principle of follow-up costs insurance for cosmetic procedures comes into play: it covers medically necessary treatment arising as a result of the insured procedure, regardless of whether the complication was foreseeable or not.
Post-operative nausea following cosmetic surgery: what does this mean for you?
- Procedures such as liposuction, tummy tucks and breast surgery are among the high-risk procedures for PONV
- General anaesthesia is standard practice for many cosmetic procedures, which automatically increases the risk of PONV
- PONV is not uncommon and is not a glitch, but the resulting costs can be substantial
- Follow-on costs insurance provides cover against unexpected treatment costs
Many cosmetic procedures are carried out under general anaesthesia. This applies to liposuction, extensive tummy tucks, breast augmentation and combined procedures. These operations fall into several categories that are clinically considered to carry an increased risk of PONV: they involve the abdominal cavity, often last more than 60 minutes and require deep general anaesthesia.
This depends crucially on whether the original procedure was medically necessary or carried out at the patient’s own request. In the case of cosmetic surgery paid for privately, the following applies: if post-operative nausea arises as a complication, the costs of follow-up treatment can be claimed back from the health insurance fund, even if the nausea itself requires medical treatment.
In practical terms, this means that whilst emergency treatment for PONV is initially covered by the health insurance fund, the fund may subsequently reclaim the costs incurred from the patient. In individual cases, these claims for reimbursement can amount to several thousand euros.
Follow-up costs insurance provides cover against precisely these recovery claims, with cover of up to 300,000 euros.
The treatment of post-operative nausea in the recovery room generally involves manageable costs for anti-emetics and medical care. The situation becomes critical if PONV leads to a prolonged hospital stay or if a complication such as aspiration or wound dehiscence arises as a result of the gag reflex.
An additional stay in hospital can easily cost between 500 and 1,500 euros a day. In the event of serious complications such as Mendelson’s syndrome (aspiration pneumonia), intensive care treatment can run to substantial five- or six-figure sums.
In the case of cosmetic procedures, the patient will, in case of doubt, bear these costs themselves, or the health insurance fund will seek reimbursement.
Even with optimal prophylaxis, PONV cannot be completely ruled out. Even with consistent dual prophylaxis and the avoidance of risk factors, post-operative nausea occurs in some patients, particularly those with a high Apple score.
Furthermore, not all operations are suitable for regional anaesthesia. In the case of major cosmetic procedures such as a tummy tuck or breast augmentation, general anaesthesia is often unavoidable, which inherently increases the risk of PONV.
The remaining residual risk may have financial consequences, which are covered by follow-up cost insurance as a preventative measure.
As a general rule, the more extensive the procedure under general anaesthesia and the greater the number of Apple Score risk factors present, the more important it is to have financial protection. Procedures such as liposuction, tummy tucks, breast augmentation or rhinoplasty are routinely carried out under general anaesthesia and are among those associated with an increased risk of PONV.
You can take out follow-up costs insurance with 4beauty up to 24 hours before the procedure, even if the date of the operation has already been set.
Insurance cover from 35 euros a year.
PONV itself is primarily a side effect associated with anaesthesia. It becomes relevant to insurance matters when it leads to a complication requiring treatment: for example, aspiration pneumonia, wound dehiscence caused by the gag reflex, dehydration requiring hospitalisation, or if the health insurance provider recovers the costs of emergency treatment incurred in connection with the insured procedure.
4beauty’s follow-up costs insurance covers medically necessary treatments and protects against claims for reimbursement from health insurance providers, up to a sum insured of 300,000 euros.
Furthermore, the typical patient planning cosmetic surgery is, statistically speaking, female; as such, she already presents the strongest single risk factor in the Apfel score. Combined with non-smoking status and the post-operative administration of opioids for pain management, this quickly results in a moderate to high risk of PONV.
What does this mean in practical terms for planning?
Make a point of raising the subject of PONV during your pre-operative consultation with your anaesthetist. Ask about targeted prophylaxis and whether TIVA (total intravenous anaesthesia) is an option for your procedure. Inform the medical team of any previous experiences of nausea following anaesthesia or of any known susceptibility to travel sickness.
Should PONV nevertheless occur and result in follow-up treatment, you will be faced with the question of who bears the costs if you have had cosmetic surgery paid for privately. Statutory health insurance funds do not cover these costs for cosmetic procedures, or only do so under very strict conditions. 4beauty’s follow-up costs insurance offers transparent cover in such cases and can be taken out up to 24 hours before the procedure. You can find out more about this in the frequently asked questions.
With 4beauty’s follow-up treatment insurance, medically necessary follow-up treatment is covered, even if PONV or other complications arise unexpectedly.
Frequently asked questions about post-operative nausea
PONV stands for Post-operative Nausea and Vomiting, in German: postoperative nausea and vomiting. This refers to nausea, retching or vomiting that occurs within the first 24 hours following a surgical procedure under general anaesthesia. In German-speaking countries, the abbreviation PÜWE (postoperative nausea and retching/vomiting) is also occasionally used. PONV is considered one of the most common complications following general anaesthesia.
Post-operative nausea usually subsides within 6 to 24 hours after surgery in most patients. In rare cases, particularly in high-risk patients or following procedures involving prolonged anaesthesia, symptoms may persist for up to 72 hours. If vomiting persists for longer than this or occurs more than three times within 24 hours, medical advice should be sought to rule out dehydration or other complications.
Yes. According to the Apfel Score, female gender is considered one of the four established major risk factors for PONV. Statistically, women have a risk that is approximately two to three times higher than that of men. This difference is hormone-related and can be effectively reduced through targeted prophylaxis, for example with ondansetron or dexamethasone. You should therefore always inform the anaesthesia team of your medical history.
The TIVA (Total Intravenous Anaesthesia) General anaesthesia using propofol as the active ingredient is considered to be the form of general anaesthesia with the lowest incidence of PONV. Propofol itself has mild antiemetic properties and does not contain any inhalation anaesthetics, which are among the strongest triggers of PONV. Avoiding nitrous oxide also significantly reduces the risk. If you are at increased risk of PONV, you can specifically ask your doctor about TIVA as an alternative.
In the case of cosmetic procedures paid for privately, statutory health insurance funds do not usually cover any resulting follow-up treatment, or only cover a proportion of the costs. If complications arising from PONV result in additional treatment – such as a prolonged stay in the recovery room, an unplanned hospital admission or follow-up medication – these costs often have to be borne by the patient themselves. Follow-up costs insurance for cosmetic procedures can provide targeted cover in such cases and covers medically necessary follow-up treatment.
In most cases, PONV is unpleasant but not dangerous. The most serious complication is the aspiration of stomach contents into the airways, which can cause chemical pneumonia (Mendelson’s syndrome); this risk is particularly high immediately after anaesthesia. Severe retching can also put strain on fresh surgical sutures. Persistent nausea and vomiting can lead to dehydration. It is therefore important to implement targeted preventative measures and, if necessary, provide prompt treatment in the recovery room.