Side Effects of General Anesthetics
Feb 02, 2015
General anesthesia is administered when you have to undergo a long or painful operation. A medicine or combination of medicines is given intravenously or made to be inhaled after you become unconscious. General anesthesia affects the whole body and you will not be able to feel any pain during this period. Usual side effects of general anesthetics are amnesia and relaxation of muscles of the entire body.
When Will General Anesthetics Be Used?
When the patient is required to be unconscious or it is safer for him during the procedure, a general anesthetic will be given. When the surgery is expected to be on for a long duration or is going to be very painful, general anesthesia is preferred. For example, hysterectomy, hernia repair, gall bladder removal, heart surgery etc.
Depending on the medical history, any known allergies in the family and the type of surgery the anesthetic will be decided. The anesthetic would also ask if the patients smokes or drinks alcohol or is on any medication.
The anesthetic gives clear instructions on things to be done before and after the surgery and helps in clearing any doubts and concerns.
Side Effects of General Anesthetics
Common Side Effects of General Anesthetics
- Nausea and vomiting post-surgery: General anesthetics can cause nausea and vomiting after surgery. This can last for few hours to days and is treated by prescribing anti-emetics.
- Sore throat: This usually happens when there is a tube inserted in the throat to aid in breathing. The pain can persist for few hours to days and is treated with pain medication.
- Dizziness and faintness: The anesthetic can cause a drop in the blood pressure which will cause you to feel dizzy and faint. Reduced intake of fluids will also be responsible for this. This is countered by giving fluids and drugs by drips. It also depends on how long it takes to get over a general anesthetic.
- Shivering: This might be if the body gets cold during or after the operation. The drugs can also cause this. Hot air blankets are used to maintain the body temperature.
- Headache: Headache can be caused by anxiety, the surgery, anesthetic and dehydration. Severe headaches can be caused if the anesthetic was given as spinal or epidural. For this special treatment might be required.
- Itching: Side effect of an opiate like morphine or allergy to other material used in the surgery can cause itching. Drugs are given to alleviate it.
- Backache, pain and other aches: This is usually due to the extended period spent on the operating table which is firm and hard. Some drugs are known to cause pain when injected
- Bruising and soreness: If a thin vein bursts at the site of injection or drip, it can cause bruising. It can also be caused due to movement of a joint or infection. It usually heals on its own, but if it becomes uncomfortable, the position of drip is changed.
- Confusion or memory loss: This particular side effect of general anesthetic is seen in older people and is usually temporary but can rarely get permanent.
- Chest infection: This is seen generally in smokers and can cause difficulty in breathing. It is advised to give up smoking prior to surgery.
- Bladder problems: Sometimes when the anesthesia is given as an epidural, it can cause men to have difficulty in urination and women might leak. A urinary catheter is inserted for some time till this side effect goes away.
- Muscle pain: Emergency surgery requires a drug called suxamethonium to be administered, since the stomach is not empty. This drug can cause muscle pain since it is a muscle relaxant.
Uncommon Side Effects of General Anesthetics
- Difficulty in breathing: Some drugs cause breathing to slow down and drowsiness after the surgery. Also, if the effects of the drugs like muscle relaxants are not fully reversed it can cause the breathing muscles to be weak. Other drugs are prescribed to counter this.
- Damage to teeth, lips and tongue: Minor damage is sometimes seen to the lips and tongue. If the teeth are weak, or if the mouth or jaw is small or if the neck is stiff, the tube inserted in the airway can cause damage.
- Worsening of existing condition: A person is operated only when he is deemed fit for it. However, if the person has previously had a heart attack or stroke, it can happen again. Also, it is essential to monitor diabetes and hypertension during surgery.
- Awareness: This is when you become aware or conscious during some part of the surgery even after being given a general anesthetic. Although the amount of anesthetic in the body is constantly monitored, this can occur and should be brought to attention of the anesthetic after the surgery.
Rare Side Effects of General Anesthetics
- Eye damage: Eyes are protected during surgery; however, it is possible that the sterilizing fluids enter the eye or get into the eye when you rub the eye after the surgery. It can cause damage to the eye surface and is temporary. Serious and permanent damage is very rare.
- Severe allergy to drugs: Allergy to drugs should be noticed and treated immediately. It rarely causes death. However, the doctor should be informed of any known allergies.
- Nerve damage: This can occur when a nerve is damaged while giving anesthetic or during operation. It is rare and usually temporary. It can sometimes be permanent.
- Death: A very rare occurrence, only around 5 in a million in UK.
- Equipment failure: There can be failure of vital equipment like anesthetic gas supply or ventilator. Since they give warning, backups can be used.
How Long Does It Take to Get Over a General Anesthesia?
General anesthesia cannot be avoided when there is a lengthy surgery and it might even sound a bit scary for some people. When you are facing such a condition, never hesitate to ask any questions concerning the process. However, there is no need to worry too much as the anesthesia team will ensure your safety during the anesthesia.
Generally speaking, how long for general anesthesia to wear off depends on each individual and the kind of anesthesia. Regarding the differences of the surgeries, the surgical interventions and the anesthesia will differ. By the time you wake up from anesthesia, it is still necessary to be monitored for several hours for the general anesthesia to wear off. Always ask your doctor about when you can leave the hospital. For the first few days after leaving the hospital, do take yourself and rest more.
What About Complications and Risks?
Since general anesthesia affects the whole body, it causes more risks and complications as compared to local anesthesia. Usually they are minor and easy to manage. Patients are advised to be on empty stomach at least 8 hours prior to surgery to avoid the food being aspirated into the lungs from the stomach. The tube inserted in the airway also prevents this from happening.
Some of the rare and serious complications of general anesthesia are:
- Heart attack, heart failure or stroke
- High or low blood pressure
- Pneumonia or other breathing problems
- Muscle damage and rapid increase in body temperature
- Reactions to medicine used in anesthetic
- Difficulty in placing the breathing tube
- Death