What do the tests before surgery mean?

A number of tests may be performed to investigate the cause of your chest symptoms or abnormal findings on your X-ray. You may require one or more of the investigations below which are used to diagnose infection, pneumonia, scar tissue or more serious conditions such as tuberculosis or lung cancer. Sometimes tests need to be repeated to ensure the correct diagnosis. Some of these test results will be available immediately but most tests will take several days for the results to be ready. If you have any tests carried out you should have a follow up appointment made before you go home. If for some reason this has not happened or if you have additional questions please contact your clinical nurse specialist.

Before surgery we do tests to check your fitness and for unexpected problems that may need to be taken into consideration. Some tests help us plan how to do the operation.

Flexible bronchoscopy

A bronchoscopy is a common test performed to examine the lungs and airways and is carried out under local anaesthetic. A doctor passes a thin flexible tube called a bronchoscope through the nose or mouth, through the windpipe (trachea) and into the lungs. Photographs and samples or biopsies can be taken. Samples are then examined under a microscope and results discussed with you at the next clinic visit.

Endobronchial ultrasound

An endobronchial ultrasound (EBUS) is a similar test to a bronchoscopy and performed under local anaesthetic and sedation. The bronchoscope has an ultrasound probe attached which allows the doctor to see any enlarged lymph nodes through the wall of the wind pipe and take a biopsy via a needle passed through the bronchoscope. These samples are then examined under a microscope and results discussed with you at the next clinic visit.

CT (Computerised Tomography) scan

CT scans use special X-ray equipment to obtain many images from different angles. A specially designed computer programme joins the images together to show detailed pictures of the inside of the body. A CT scan can help to give more information regarding the abnormality seen on your X-ray. The scan is painless and takes around 10 minutes. CT scans give a small amount of radiation, which is very unlikely to harm you. You can usually go home as soon as the scan is over.

CT guided biopsy

Sometimes the CT scan shows an abnormal area or shadow that is close to the outside of the lungs or in a position that is easy to access by using a biopsy needle. A radiology doctor will usually take the biopsy and decide the best place to take it from using the CT scanner. The biopsy usually takes about 15 minutes and some discomfort is possible. A local anaesthetic is injected into the area before the biopsy is taken to reduce any discomfort.

Echocardiogram test (echo test)

This is a similar test to an ultrasound scan (see below) but is done to examine your heart function. It is usually suggested if you have some history of heart problems and can be recommended prior to surgery.

Ultrasound scan

Ultrasound uses high frequency sound waves which are transmitted through the skin to build up a picture of the inside of your body. This is the same sort of test used on pregnant women. Ultrasound imaging is painless, usually fast and easy. You will be asked to lie on your back on an examining table. Gel is put onto the skin in the area to be scanned and a small, hand-held scanner is passed over that area. A computer converts the reflected sound waves into a picture on a television screen.

The procedure is not painful, but there may be varying degrees of discomfort from pressure as the probe moves over your skin. The process takes around 10 to 15 minutes.

Lung function tests

These simple tests involve blowing into machines via a mouthpiece. They record how much air you can breathe in or out and how much oxygen you can absorb. This gives an estimate of how well your lungs are working. The results may help decide on appropriate treatment for you if have other lung conditions, such as emphysema or Chronic Obstructive Pulmonary Disease (COPD).

Exercise tests

Exercise tests give a measure of your overall fitness. They are sometimes recommended if there is reason to suspect your heart or lungs have a degree of limitation on their function. The tests may be done in the various ways.

Measuring the distance you are able to walk in a set time.

Recording the activity of your heart with an ECG and recording the activity of your lungs by breathing into a tube whilst you exercise. This may be on a treadmill or an exercise bike.

Perfusion or ventilation scan

This is a simple test sometimes suggested to assess how well supplied your lungs are with blood or how the airflow is distributed in the lung. It may be recommended to gain further information on how well a specific part of the lung is working, particularly if you have an existing lung condition. It takes about 20 minutes and involves having an injection of a radioactive substance which develops a picture on a computer screen.

PET (Positron Emission Tomography) scan

A PET scan is an imaging technique that uses small amounts of a radioactive tracer (similar to sugar).   The levels of radiation involved are very small and considered safe. It produces images on a television screen, highlighting possible abnormalities. A PET scan highlights parts of the body where the cells are most active. Cells may be more active for a number of reasons, these include infection inflammation and cancer. A PET scan cannot tell us precisely why cells are more active. Combining the PET images with CT images can give important information to help plan appropriate treatment. The scan is useful in helping to determine the likely stage of cancer.

Sputum test

Examining a sample of your phlegm (sputum) may assist in establishing if you have a chest infection or abnormal cells in the lung.

Blood tests

Before an operation we routinely check the function of your kidneys and liver, blood clotting and blood group. We check for anaemia (your haemoglobin level), the levels of white blood cells and platelets. These can usually all be done from taking blood samples from one needle.

You will have a blood test the first day after your operation and again if we need to monitor one of the tests more closely.

 

MRI scan

MRI scan make pictures using magnets, not radiation. Water and fat in the body have a typical appearance on an MRI scan. They are very useful for assessing lumps near the spine. The scan involves lying in a tube, if you panic in enclosed spaces let us know.

 

Biopsies

A biopsy means taking a small piece of tissue from the body and sending it for analysis in the laboratory. This can involve looking at the tissue structure under a microscope. It helps us diagnose the cause of certain lumps in the body. There are different ways of taking a biopsy. Sometimes the biopsy doesn’t tell us the diagnosis. This may be because the piece of tissue was too small or there was too much scar tissue.

 

ECG (electrocardiogram)

This is commonly referred to as a heart tracing. 12 stickers are placed on the chest and connected to leads. The electrical activity in the heart is measured and printed out. This allows doctors to assess the heart rhythm. The tracing is painless.

 

Histology

Lung tissue and lymph glands which are removed are sent to the laboratory to be examined under the microscope, this is called histology. It is a delicate process and typically takes 2 weeks to get results. Histology can help us diagnose lung disease and also assess the stage of lung cancer. Histology results will be discussed with you in clinic.

 

Surgery for diagnosis

Sometimes all of these tests still do not give us clear answer about diagnosis of a disease. Surgery may be recommended both to get a diagnosis and help treat symptoms.

The following are operations that may be done to get a diagnosis:

 

Cervical mediastinoscopy

Anterior mediastinotomy

Pleural biopsy

Lung biopsy

Bronchoscopy

Frozen section