Blood Typing, Screening and Crossmatching in Sharjah

What is blood typing, screening and crossmatching?

Blood typing, screening and crossmatching are the three blood bank tests that make a transfusion safe. Each answers a different question:

| Test | What it checks | When it is used |
|---|---|---|
| Blood typing (group) | Your ABO group (A, B, AB or O) and whether you are Rh (D) positive or negative | Pregnancy, before surgery, before any transfusion |
| Antibody screen | Whether your plasma carries antibodies against other red cell markers | Pregnancy, before surgery, before transfusion |
| Crossmatch | Whether a particular donor unit is compatible with your blood | When a transfusion is planned or likely |

Blood groups go beyond A, B and O. Red cells carry many other markers, and a person can form antibodies to them after a previous transfusion or pregnancy. The antibody screen finds these, so the blood bank can select units that suit you in advance.

At Dar Al Kamal Hospital, Sharjah, the blood bank is part of the hospital laboratory, which runs 24 hours a day. It provides typing, screening, crossmatching and component support, meaning red cells, plasma and platelets prepared for the patient who needs them.

Who needs it

The most common reasons are:

• Before surgery. A "group and screen" is often part of the pre-operative assessment for operations where bleeding is possible. The blood bank then keeps your sample ready and crossmatches units quickly if they are needed.
• In pregnancy. Every pregnant woman has her blood group and antibody screen checked early in antenatal care, and the screen is usually repeated later in pregnancy. Women who are Rh negative are offered anti-D immunoglobulin at set points to protect future pregnancies, and the baby's blood group may be checked after birth.
• Severe anaemia or bleeding. People with very low haemoglobin, covered on the anaemia treatment page, and patients with bleeding in the emergency department may need a transfusion.
• Planned or repeat transfusions for blood conditions or during treatment on the wards.

What happens

The blood bank sample is a routine blood draw from a vein in your arm, with one important difference: identification is checked with particular care. Staff confirm your full name, date of birth and hospital number before the draw, and the tube is labelled at your side. If this is your first sample at Dar Al Kamal Hospital, you may be asked for a second sample taken separately to confirm your group.

In the laboratory, your red cells and plasma are tested against reagents to establish your group, and your plasma is screened for antibodies. When a transfusion is planned, a matching unit is selected and crossmatched against your sample. If an antibody is found, the team selects units that lack the matching marker, which can take extra time, so an early sample helps.

If a transfusion goes ahead, the procedure is explained and your consent is recorded. A nurse checks your identity against the unit once more at the bedside, then monitors your temperature, pulse and blood pressure closely, especially in the early part of the transfusion.

Preparing for it

Blood typing and crossmatching need no fasting, and you can take your usual medicines. Drink water so the vein is easy to find.

Before a planned operation, attend the pre-operative blood test on the day you are given, because a crossmatch sample is valid for a limited period and is timed to your surgery date. Tell the team:

• about any previous blood transfusion, and any reaction to one;
• about all past pregnancies, including miscarriages;
• if you already know your blood group, or carry a card listing a red cell antibody;
• if you have personal or religious views about receiving blood, so these can be discussed well in advance.

Bring your Emirates ID, insurance card and any blood group card or report from another hospital.

Afterwards

After a blood bank sample, you can return to your normal day. A small bruise at the needle site is common.

Your blood group is recorded in your hospital file. Keep a note of it, together with any antibody the laboratory reports, because this information helps every future hospital that treats you. If you are Rh negative and pregnant, your antenatal team explains when anti-D is offered.

During or after a transfusion, tell the nurse immediately if you feel hot, shivery, itchy, breathless, or have pain in your back or chest. After you go home, contact the hospital urgently or go to the emergency department if you develop a fever, dark urine, yellowing of the skin or eyes, or breathlessness in the days following a transfusion.

Cost and insurance

Most UAE insurance plans cover blood typing, antibody screening and crossmatching as part of approved surgery, maternity care or an emergency admission. Blood components given during an approved admission are usually covered within that admission, and planned transfusions may need pre-approval. Dar Al Kamal Hospital, Sharjah can help you check your cover on 06 599 7777.