Complications in anesthesia


As with any medical procedure, various complications can occur during anaesthesia, i.e. the anaesthetic of the body for an operation. In most cases the risk of complications occurring during anaesthesia is very low, but the patient should be aware of this. Before every operation, a patient must be informed by his or her anaesthetist, i.e. the doctor who initiates the anaesthesia and remains with the patient for monitoring during the operation. This means that the patient receives an information sheet describing possible complications during the anaesthesia and the anaesthetist talks to the patient before the operation so that the patient can ask questions and communicate possible fears to the doctor.

Frequency distribution

Serious complications during anaesthesia are very rare and occur mainly in older patients who already had little movement before the operation or who suffer from several diseases. In total, approximately 0.4 out of 100,000 previously healthy patients in Germany die during anesthesia without previous illnesses. This shows that the risk is very low and is constantly decreasing, above all due to constant monitoring and the development of new and better narcotics.

Slight complications under anaesthesia are more frequent, however. Every fifth patient complains of nausea after the operation and bruises at the injection site are not uncommon. However, it should be noted that without the operation many patients would definitely die. It is therefore always important to weigh up the benefits against the risks and, in case of doubt, to accept one day of nausea.

Most frequent complications

Complications can occur during and after the operation if the patient is under anaesthesia. This happens very rarely. However, the patient must be informed about the possible risks before every operation.

Complications can occur under general anaesthesia, spinal anaesthesia or local anaesthesia. The most common complication of general anaesthesia is nausea, which can occur after the operation due to the medication. In case of very strong nausea and vomiting after an anaesthetic, drugs against nausea can be administered both after the operation and as a preventive measure during the anaesthetic.

In addition, it often happens that the patient feels very cold and trembles after the operation. Through the tube that is inserted into the trachea for ventilation, hoarseness and sore throat can occur after the operation. In rare cases, the teeth or gums are damaged during intubation.

Due to the tube, the patient may vomit during the operation and this may enter the airways. This can lead to serious complications as the lung tissue is very sensitive to stomach acid. This is the reason why patients must fast before the operation.

In the places where the anaesthetist places the access, i.e. usually in the crook of the arm, post-operative bleeding or bruising may occur or nerves may be injured. Particularly in older patients, a state of confusion with delusions and disorientation can occur after the operation. For this reason, especially in older people, care is taken to ensure that the anaesthetic dose is very low or a local anaesthetic is used.

Complications can also occur during the operation. These include allergic reactions, which are mainly triggered in response to certain drugs. Latex, which is contained in various surgical materials, can also trigger allergic reactions.

These manifest themselves as reddening of the skin, shortness of breath or circulatory failure. In addition, the so-called malignant hyperthermia can occur if there is a genetic predisposition. Although this is extremely rare, it is considered life-threatening for the patient.

After the muscle relaxant is administered during the induction phase of anaesthesia to relax the muscles, the patient suffers from muscle rigidity, an increase in body temperature, palpitations and, as a consequence, metabolic and organ failure. However, the patient can be treated by the timely administration of certain drugs. During an operation, disturbances of the cardiovascular system can occur because the body’s own regulatory mechanisms have been switched off by the anaesthetic.

This can lead to drastic changes in blood pressure or even to cardiac arrhythmias up to cardiac arrest. However, these are exceptional cases, which can occur preferentially in people with existing heart disease. The anaesthetist monitors the patient very closely during each anaesthesia so that any changes in heart rate can be detected immediately. In addition, intraoperative waking states may occur. This occurs extremely rarely and is usually due to an insufficient effect of the anaesthetic medication due to drug abuse.