Having Major Surgery

Major surgical procedures carried out under general or regional anaesthesia

Major surgery always takes place in hospital and usually involves a procedure performed on tissue deep inside the body. For example, surgery to remove a section of intestine or implant an artificial hip would be considered major surgery (see Types of surgery).

Before you undergo a major surgical procedure, your doctor will discuss with you why surgery is necessary, exactly what the procedure involves, where the operation will take place, and how long it will take. You will be fully informed about possible risks associated with the operation, and you will be asked to sign a consent form to say that you understand the risks and agree to surgery.

Before the procedure is performed, your general health and fitness for surgery will be assessed. On the day of the operation, you will be prepared for surgery and given an anaesthetic. Usually, major surgery is performed under general anaesthesia (see Having a general anaesthetic). However, an increasing number of procedures are now carried out under regional anaesthesia (see Having a regional anaesthetic), in which you remain fully conscious but free of pain. A sedative may be given along with regional anaesthesia to help to keep you calm and reduce anxiety. The type of anaesthesia you have depends largely on the nature of the procedure, but your general health and age may also play a part.

After the operation has been completed there is a recovery period. An increasing number of operations now need only a short recovery period in hospital – often only 24 hours – although it may sometimes be necessary to stay in hospital for several days or longer. Your doctor will be able to advise you on how long it will take for you to recover from your operation. There may be particular practical issues that you wish to clarify with the doctor. For example, you may want to check whether further treatment will be needed after the operation and how long it is likely to be before you are able to carry out your normal day-to-day activities.

Preoperative assessment

Before you undergo a major surgical procedure, you will be given a preoperative assessment. The main purpose of this assessment is to find out whether you have an underlying medical condition, such as heart disease, that may require special precautions during the operation in order to minimize the risk of complications developing.

During the preoperative assessment, a doctor reviews your medical history and carries out a physical examination. Routine tests, such as blood tests and an ECG to assess the condition of your heart, will also be carried out, together with any other investigations that may be needed because of your age, general health, or an underlying condition.

You may also be seen by an anaesthetist, who checks your suitability for anaesthesia, discusses how the anaesthetic will be administered, and answers any questions you may have.

Medical history and examination

You will be asked about your current condition and about other serious illnesses or allergies you have experienced in the past (see Medical history). It is important to tell the doctor about any allergies, and also about any medications (including complementary remedies) you are taking because they may affect the safety of the surgery. It is helpful if you bring any medications and/or complementary remedies with you to show the doctor.

You will then be given a full medical examination (see Physical examination) to help identify any underlying medical conditions that may increase the risk of complications developing either during or after the operation.

Routine tests

You may have a number of routine tests, many of which require a sample or blood or urine to be taken. Blood tests usually require no more than two or three small tubes of blood to be withdrawn through a single needle. A full blood count of your red and white blood cells and the level of haemoglobin (the oxygen-carrying molecule in red blood cells) will usually be checked. The levels of certain chemicals, such as urea and salts, in your blood may be measured because they reflect the function of organs such as the kidneys. Your blood group may be checked and a sample of blood may be saved for cross-matching against blood from the blood bank if you need to have a blood transfusion during surgery.

In addition to these tests, you may also be given an ECG (electrocardiogram) to check the condition of your heart, particularly if your medical history suggests that you may have a heart condition.

Other presurgical investigations

Depending on the outcome of your initial physical examination, your doctor may decide that other investigations are needed before you undergo surgery. For example, if there is a possibility that you have a heart or lung disorder, a chest X-ray may also be performed. The results of these tests may influence how the surgery is carried out and the level of monitoring that is required during the operation. In some cases, these initial test results indicate the need for further investigations, such as exercise testing, which evaluates the flow of blood to the heart while a person is at rest and during the physical stress of exercise.

Preparations for surgery

On the day of your surgery, you will be prepared for the operation. After arriving in the operating theatre, you will then be given the anaesthetic.

You should not eat or drink non-clear fluids for about 6 hours before an operation under general anaesthesia. If you have food in your stomach there is an increased risk of vomiting while you are unconscious. If the acidic contents of the stomach are inhaled, serious damage to your lungs may result. You may drink clear fluids up to about 2 hours before the operation. You may also need to fast if you are having a regional anaesthetic, in case it becomes necessary to give you a general anaesthetic during surgery.

General preparations

An hour or two before your operation, you will be asked to remove all jewellery and to change into a surgical gown. You will be asked to remove dentures, if you have them, or to point out loose teeth or crowns, which could be damaged when the breathing tube for anaesthetic gases is inserted. If a surgical incision is to be made in an area of skin that is covered with hair, the area may be shaved to make the skin easier to clean. The surgeon will mark your skin on the side of the operation or around the operation site. To reduce the risk of blood clots forming in the legs (see Deep vein thrombosis), you will probably be asked to wear special calf compression stockings, and you may also be given an injection of heparin (see Drugs that prevent blood clotting). Just before your operation, a nurse will take you to the operating theatre.


When you arrive in the operating theatre, you will be given an anaesthetic. For longer operations carried out under general anaesthesia, the anaesthetic is given in two parts. First, an anaesthetic is injected into a vein on the back of your hand. Although this injection induces anaesthesia rapidly, it is not long-lasting. Second, inhaled gases are given to maintain unconsciousness. For shorter operations, a single injected or inhaled anaesthetic may be used.

The initial anaesthetic drug is injected into a thin plastic tube called a catheter. This tube is inserted into a vein either in the back of your hand or in your arm, and the anaesthetic drug causes almost immediate loss of consciousness.

The anaesthetist then inserts a breathing tube, called an endotracheal tube, through your mouth and down into your trachea (windpipe). The tube is connected to a ventilator, which regulates the speed and depth of breathing throughout surgery. You will be given a mixture of gases to breathe, including oxygen and an inhaled anaesthetic. You will also be given a drug through the catheter that relaxes your muscles and therefore makes it possible for the surgeon to cut and move muscles easily. By doing this, the surgeon can obtain a clear view of the operating area.

If you are having a regional anaesthetic, the anaesthetic drug is given by injection. The site of the injection varies according to the procedure that is to be performed, and for some types of regional anaesthesia, such as epidural or spinal anaesthesia, the skin around the injection site will be numbed first with a local anaesthetic.

In the operating theatre

As soon as you are anaesthetized, the surgeon or assistant surgeon uses an antiseptic solution to clean the appropriate area of your skin. The solution used may leave pink or brown stains on the skin for a short time after the operation. The remaining nonsterile parts of your skin are covered with sterile drapes, and the procedure is then carried out. During the operation, further precautions will be taken to prevent deep vein thrombosis, such as supporting your calves and/or fitting calf vein pumps around your legs.

When the procedure is completed, the wound is closed up (see Rejoining tissue) by the surgeon. For some types of wound, you may have internal stitches as well as those that are visible on your skin. Usually, a local anaesthetic is injected around the wound to reduce any pain and the amount of painkilling drugs needed when you wake up. If you have been given a general anaesthetic, the proportion of anaesthetic gases you are breathing will be reduced and the proportion of oxygen you are given will be increased to allow you to wake up.

In the recovery room

As soon as you show signs of breathing on your own, the anaesthetist will remove the endotracheal tube. You may hear someone telling you the operation is over, but you will probably wake up only briefly. You will then be moved to the recovery room. If you have had a general anaesthetic, the recovery room is probably the first place that you will remember after the operation. When you wake up, you may have an intravenous drip in your arm, drainage tubes near the operation site, and a catheter in your bladder. For the first hours after a major operation, your temperature, blood pressure, and pulse are checked frequently. When you are taken back to the ward, usually when you are fully awake, these checks are repeated, but less frequently.

Some major surgery requires intensive nursing care afterwards and you may be transferred to an intensive therapy unit or a high-dependency unit (which provides more specialist nursing care and monitoring than is available on an ordinary ward but less than in an intensive therapy unit) rather than being taken directly back to an ordinary ward. You will be transferred to an ordinary ward when you are no longer dependent on specialized equipment and medical personnel.

Back to the ward

After major surgery, you will be transferred to the ward so that you can be monitored and given any further treatment that you may need. Postoperative monitoring is carried out in order to identify any complications as early as possible. If necessary, you will be given pain relief. Generally, the more extensive the operation, the longer it will take for you to recover. Usually, your recovery is faster and complications, such as deep vein thrombosis, are less likely to occur if you start moving around as soon as possible after the effects of the anaesthetic have worn off.

If you have had a general anaesthetic, you are likely to remain drowsy for a few hours. After regional anaesthesia, you will not experience the drowsiness that normally follows general anaesthesia. The numbing effects of a regional anaesthetic usually wear off after about an hour.

Treatment and monitoring

You may be attached to tubes and equipment that monitor your condition or help you to perform particular bodily processes. For example, you may be attached to an ECG machine that monitors your heart function. You may have a urinary catheter if surgery has involved the bladder or nearby organs, such as the prostate gland. The catheter enables medical staff to monitor the amount of urine that you produce. An intravenous drip may be placed in your arm or the back of your hand to deliver fluids and medication if necessary. Fluids help to prevent you becoming dehydrated until you are able to eat and drink normally. After certain procedures, there may be a tube called a drain coming from a small hole in the skin near the surgical wound. This tube is often attached to a vacuum bottle and allows excess tissue fluid or blood to drain away from the operation site. It is usually removed after a few days. You may also have a tube called a central line coming from the side of your neck or just below your collar-bone. This tube is held in place by stitches and is used to monitor your fluid balance and blood pressure and to give you extra fluids or drugs if these are needed. This tube will be removed as soon as continuous monitoring and fluids are no longer necessary.

Pain relief

You may not feel much pain when you wake up because of the effects of the drugs you have received during anaesthesia, and because the surgeon may have injected a local anaesthetic into the edges of the surgical wound. After a few hours, you may become more uncomfortable and require painkillers. These drugs may be administered by suppository, orally, or by injection, depending on the drug, the severity of your pain, and your ability to absorb the medication. You may be able to administer your own painkillers in small, safe doses as often as you need using a patient-controlled analgesic pump attached to a tube that is inserted into a blood vessel in your arm. This type of pump has a built-in device to prevent you from receiving too much medication.

Other treatments

Some major surgery may necessitate other treatments to prevent complications. For example, deep vein thrombosis (blood clots in the legs) may develop if you are immobile for long periods of time. These clots may break off and travel to the heart or lungs, which may be life-threatening. If clots are likely to form after surgery, your doctor will prescribe injections of a drug that reduces blood clotting. You may also need to wear support stockings for a few days until you are fully mobile.

If you have had an operation on an infected area such as an abscess, you may be given antibiotics. Depending on the type of operation you have had, you may be offered physiotherapy or other treatment while in hospital to help you to return to full mobility.

Leaving the hospital

You will be discharged from hospital when you no longer need close monitoring or special treatment. You usually need to be eating and drinking normally without the aid of tubes and to be able to pass urine without a catheter. The medical staff need to be satisfied that you have someone to accompany you home and that you will be adequately looked after if you are unable take care of yourself. Home nursing (see Home care) may need to be organized in advance. If you require special aids, such as a bath lift, you may be assessed by an occupational therapist (see Occupational therapy) before you are discharged from hospital.

Before you leave hospital, you will be provided with any medication that you need, and a follow-up appointment will be made to check on your progress and, if necessary, to remove stitches.

Procedure: Having a General Anaesthetic

Procedure: Having a Regional Anaesthetic

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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