Blood platelets, or thrombocytes, are small spherical bodies in the BLOOD, which play an important part in the process of its COAGULATION. Normally, there are around 300,000 per cubic millimetre of blood.
Composition The cellular components are red cells or corpuscles (ERYTHROCYTES), white cells (LEUCOCYTES and lymphocytes – see LYMPHOCYTE), and platelets.
The red cells are biconcave discs with a diameter of 7.5µm. They contain haemoglobin
– an iron-containing porphyrin compound, which takes up oxygen in the lungs and releases it to the tissue.
The white cells are of various types, named according to their appearance. They can leave the circulation to wander through the tissues. They are involved in combating infection, wound healing, and rejection of foreign bodies. Pus consists of the bodies of dead white cells.
Platelets are the smallest cellular components and play an important role in blood clotting (see COAGULATION).
Erythrocytes are produced by the bone marrow in adults and have a life span of about 120 days. White cells are produced by the bone
marrow and lymphoid tissue. Plasma consists of water, ELECTROLYTES and plasma proteins; it comprises 48–58 per cent of blood volume. Plasma proteins are produced mainly by the liver and by certain types of white cells. Blood volume and electrolyte composition are closely regulated by complex mechanisms involving the KIDNEYS, ADRENAL GLANDS and HYPOTHALAMUS.... blood
According to the type of cells that predominate, leukaemia may be classi?ed as acute or chronic lymphoblastic leukaemia or myeloid leukaemia. Acute lymphoblastic leukaemia (ALL) is mostly a disease of childhood and is rare after the age of 25. Acute myeloid leukaemia is most common in children and young adults, but may occur at any age. Chronic lymphatic leukaemia occurs at any age between 35 and 80, most commonly in the 60s, and is twice as common in men as in women. Chronic myeloid leukaemia is rare before the age of 25, and most common between the ages of 30 and 65; men and women are equally affected. Around 2,500 patients with acute leukaemia are diagnosed in the United Kingdom, with a similar number annually diagnosed with chronic leukaemia.
Cause Both types of acute leukaemia seem to arise from a MUTATION in a single white cell. The genetically changed cell then goes through an uncontrolled succession of divisions resulting in many millions of abnormal white cells in the blood, bone marrow and other tissues. Possible causes are virus infection, chemical exposure, radiation and genetic background. The cause of chronic lymphocytic leukaemia is not known; the chronic myeloid version may have a genetic background.
Symptoms In acute cases the patient is pale due to anaemia, may have a purpuric rash due to lack of platelets, and may have enlarged lymphatic glands and spleen. The temperature is raised, and the condition may be mistaken for an acute infection (or may ?rst become apparent because the patient develops a severe infection due to a lack of normal white blood cells).
In the chronic type of the disease the onset is gradual, and the ?rst symptoms which occasion discomfort are either swelling of the abdomen and shortness of breath, due to painless enlargement of the spleen; or the enlargement of glands in the neck, armpits and elsewhere; or the pallor, palpitation, and other symptoms of anaemia which often accompany leukaemia. Occasional bleeding from the nose, stomach, gums or bowels may occur, and may be severe. Generally, there is a slight fever.
When the blood is examined microscopically, not only is there an enormous increase in the number of white cells, which may be multiplied 30- or 60-fold, but various immature forms are also found. In the lymphatic form of the disease, most white cells resemble lymphocytes, which, in healthy blood, are present only in small numbers. In the myeloid form, myelocytes, or large immature cells from the bone marrow, which are never present in healthy blood, appear in large numbers, and there may also be large numbers of immature, nucleated erythrocytes.
Treatment This varies according to the type of leukaemia and to the particular condition of the patient. Excellent results are being obtained in the control of ALL using blood transfusions, CHEMOTHERAPY, RADIOTHERAPY and bone-marrow TRANSPLANTATION. In the case of acute leukaemia, the drugs now being used include MERCAPTOPURINE, METHOTREXATE and CYCLOPHOSPHAMIDE. Blood transfusion and CORTICOSTEROIDS play an important part in controlling the condition during the period before a response to chemotherapy can be expected. Chemotherapy has almost completely replaced radiotherapy in the treatment of chronic leukaemia. For the myeloid form, BUSULFAN is the most widely used drug, replaced by hydroxyurea, mercaptopurine, or one of the nitrogen mustard (see NITROGEN MUSTARDS) derivatives in the later stages of the disease. For the lymphatic form, the drugs used are CHLORAMBUCIL, CYCLOPHOSPHAMIDE, and the nitrogen mustard derivatives.
Prognosis Although there is still no guaranteed cure, the outlook in both acute and chronic leukaemia has greatly improved – particularly for the acute form of the disease. Between 70 and 80 per cent of children with acute lymphoblastic leukaemia may be cured; between 20 and 50 per cent of those with acute myeloid leukaemia now have much-improved survival rates. Prognosis of patients with chronic lymphocytic leukaemia is often good, depending on early diagnosis.... leukaemia
Non-opioid analgesics include ASPIRIN, PARACETAMOL and NON-STEROIDAL ANTIINFLAMMATORY DRUGS (NSAIDS), which are used to treat mild or moderate pain such as headache (see also MIGRAINE), DYSMENORRHOEA, and transient musculoskeletal pain. Some analgesics – for example, aspirin and paracetamol – also reduce PYREXIA. A strong non-opioid analgesic is NEFOPAM HYDROCHLORIDE, which can be used for persistent pain or pain that fails to respond to other non-opioid analgesics, but does have troublesome side-effects. These non-opioid analgesics can be obtained without a doctor’s prescription – over the counter (OTC) – but the sale of some has to be supervised by a quali?ed pharmacist. A wide range of compound analgesic preparations is available, combining, say, aspirin or paracetamol and CODEINE, while the weak stimulant CAFFEINE is sometimes included in the preparations. Most of these are OTC drugs. NSAIDs are especially e?ective in treating patients with chronic diseases accompanied by pain and in?ammation. They, too, are sometimes combined with other analgesics.
Paracetamol acts within the central nervous system by inhibition of PROSTAGLANDINS. It is often combined with other analgesics – for example, aspirin or codeine; in proprietary compounds and in therapeutic doses it has few side-effects. Overdosage, however, can cause damage to the liver or kidneys (20–30 tablets are su?cient to do this). Paracetamol is often used by individuals attempting suicide. Even if there are no immediate symptoms, individuals suspected of having taken an overdose should be sent to hospital urgently for treatment.
The NSAIDs (including aspirin) inhibit prostaglandin synthesis. Prostaglandins are released by tissues that are in?amed, and may cause pain at peripheral pain sensors or sensitise nerve endings to painful stimuli: by inhibiting their production, pain and in?ammation are reduced. NSAIDs are particularly e?ective for pain produced by in?ammation – for example, ARTHRITIS. Side-effects include gastrointestinal bleeding (caused by mucosal erosions particularly in the stomach), inhibition of platelet aggregation (see PLATELETS), and potential for renal (kidney) damage.
Severe pain is often treated with opioid drugs. The original drugs were naturally occurring plant ALKALOIDS (e.g. MORPHINE), whilst newer drugs are man-made. They mimic the action of naturally occurring compounds (ENDORPHINS and ENCEPHALIN) which are found within the brain and spinal cord, and act on receptors to reduce the transmission of painful stimuli within the central nervous system (and possibly peripherally). They tend to produce side-effects of euphoria, respiratory depression, vomiting, constipation and itching. Chronic use or abuse of these drugs may give rise to addiction.... analgesics
The drugs are much more e?ective in the treatment and prevention of venous clotting – for example, deep vein thrombosis (DVT), see under VEINS, DISEASES OF – than in preventing thrombosis formation in arteries with their fast-?owing blood in which thrombi contain little ?brin (against which the anticoagulants work) and many PLATELETS.
The main anticoagulants now in use are the natural agent HEPARIN (a quick-acting variety and a low-molecular-weight long-acting type); synthetic oral anticoagulants such as WARFARIN and the less-often-used acenocoumarol and PHENINDIONE; and antiplatelet compounds such as ASPIRIN, clopidogrel dipyridamole and ticlopidines. Fondaparinux is an extract of heparin which can be given once daily by injection; ximelagatran, an inhibitor of thrombin, is being trialled as the ?rst new oral anticoagulant since heparin.
Patients taking anticoagulants need careful medical monitoring and they should carry an Anticoagulant Card with instructions about the use of whatever drug they may be receiving – essential information should the individual require treatment for other medical conditions as well as for thrombosis.... anticoagulants
Habitat: Native to China and Japan. Cultivated as an ornamental.
English: Chrysanthemum.Ayurvedic: Shatapatri.Unani: Guldaaudi.Siddha/Tamil: Samanthipoo, Akkarakkaram.Action: Flowers—stomachic, aperient, anti-inflammatory. Leaves— prescribed in migraine (as circulatory stimulant). Uses same as those of chamomile.
The flowers contain daucosterol, cumambrin-A, glyceryl-l-monobehe- nate and palmitic acid. The flowers also contain chrysanthemol which showed strong anti-inflammatory activity in mice. The flavones, apigenin and lu- teolin, are reported to exhibit marked antitumour activity.Flowers yield an essential oil containing camphor (16.0%), trans-cara- ne-trans-2-ol (15.0%), bornyl acetate (12.0%) and sabinene (7%).A related species C. parthenium (Linn.) Berhh., Feverfew, synonym Tanacetum parthenium, used for the management of migraine in Western herbal, is found in Jammu and Kashmir. The plant extracts have a powerful and prostaglandin-independent inhibitory effect on the secretion of granule content by leucocytes and platelets. The inhibition of the agonist-induced serotonins release by platelets could be accounted for the benefit in migraine. The compound responsible for the anti-secretory activity has been identified as sesquiterpene alpha-methylene- gamma-lactone derivatives; partheno- lide being the main constituent of the lactones. (Two fresh or frozen leaves a day are chewed or capsules or pills containing 86 mg of the leaf material is taken for migraine. Fresh leaves may cause mouth sores.)... chrysanthemum indicumThe three-stage process of coagulation is complex, involving many di?erent substances. There are two cascading pathways of biochemical reactions for activating coagulation of blood. The extrinsic pathway is the main physiological mechanism, which is triggered when blood vessels are damaged, usually by trauma or surgery. The intrinsic pathway is activated by internal disruption of the wall of a blood vessel. The basic pattern is broadly the same for both and is summarised simply as follows:
prothrombin + calcium + thromboplastin
thrombin + ?brinogen
?brin
Prothrombin and calcium are normally present in the blood. Thromboplastin is an enzyme which is normally found in the blood platelets and in tissue cells. When bleeding occurs from a blood vessel, there is always some damage to tissue cells and to the blood platelets. As a result of this damage, thromboplastin is released and comes into contact with the prothrombin and calcium in the blood. In the presence of thromboplastin and calcium, prothrombin is converted into thrombin, which in turn interacts with ?brinogen – a protein always present in the blood – to form ?brin. Fibrin consists of needle-shaped crystals which, with the assistance of the blood platelets, form a ?ne network in which the blood corpuscles become enmeshed. This meshwork, or CLOT as it is known, gradually retracts until it forms a tight mass which, unless the tissue injury is very severe or a major artery has been damaged, prevents any further bleeding. It will thus be seen that clotting, or coagulation, does not occur in the healthy blood vessel because there is no thromboplastin present. There is now evidence suggesting that there is an anti-thrombin substance present in the blood in small amounts, and that this substance antagonises any small amounts of thrombin that may be formed as a result of small amounts of thromboplastin being released.
The clotting or coagulation time is the time taken for blood to clot and can be measured under controlled conditions to ensure that it is normal (3–8 minutes). In certain diseases – HAEMOPHILIA, for example – clotting time is greatly extended and the danger of serious haemorrhage enhanced.... coagulation
Hin: Patharchur;
Ben: Paterchur;Mal: Panikkurkka, kannikkurkka;Tam: Karpuravalli;Kan: karpurahalli;Tel: Sugandhavalkam.It is found through out the tropics and cultivated in homestead gardens. It is a large succulent aromatic perennial herb with hispidly villous or tomentose fleshy stem. Leaves are simple, opposite, broadly ovate, crenate and fleshy. Flowers are pale purplish in dense whorls at distant intervals in a long slender raceme. Fruits are orbicular or ovoid nutlets. The leaves are useful in cephalagia, otalgia, anorexia, dyspepsia, flatulence, colic, diarrhoea, cholera, halitosis, convulsions, epilepsy, cough, asthma, hiccough, bronchitis, strangury, hepatopathy and malarial fever (Warrier et al,1995).2. Coleus vettiveroides K.C. Jacob, syn. Plectranthus vettiveroides (Jacob) Singh & Sharma.San: Valakam, Hriberam;Hin: Valak;Mal: Iruveli;Tam: Karuver;Tel: Karuveru,It is seen in tropical countries and cultivated in gardens. It is a small profusely branched, succulent aromatic herb with quadrangular stems and branches and deep straw coloured aromatic roots. Leaves are glandular hairy, broadly ovate with dentate margins and prominent veins on the bark. Blue flowers are borne on terminal racemes. Fruits are nutlets. The whole plant is useful in hyperdipsia, vitiated conditions of pitta, burning sensation, strangury, leprosy, skin diseases, leucoderma, fever, vomiting, diarrhoea, ulcers and as hair tonic.3. Coleus forskohlii Briq. syn. C. barbatus Benth.Hin: Garmai
Kan: Maganiberu, MakandiberuGuj: MaimulIt is a perennial aromatic herb grown under tropical to temperate conditions for its carrot-like tubers which are used as condiments in the preparation of pickles. Its tuberous roots are an exclusive source of a diterpenoid forskolin which has the unique property of activating almost all hormone sensitive adenylate cyclase enzymes in a biological system. It is useful in the treatment of congestive heart failure, glaucoma, asthma, cancer and in preventing immature greying of hair (Hegde,1997).Agrotechnology: The Coleus group of plants grows in tropical to subtropical situations and in warm temperate climatic zone on mountains of India, Nepal, Burma, Sri Lanka, Thailand and Africa. It comes up well on the sun exposed dry hill slopes from 300m to 1800m altitude. A well drained medium fertile soil is suitable for its cultivation. it is propagated vegetatively through stem and root cuttings. Vine cuttings to a length of 10-15cm from the top portion are most ideal for planting. The land is ploughed or dug to a depth of 15-20cm and ridges are formed 30cm apart. Vine cuttings are planted on the ridges at 30cm spacing after incorporating basal manure. 10t of FYM and NPK at 50:50:50kg/ha are incorporated into the soil. Top dressing of N and K is also suggested for improved yields. Weeding and earthing up at 45 days after planting along with topdressing is highly beneficial. Bacterial wilt and root knot nematode are reported in the crop. Drenching the soil with fungicide, deep ploughing in the summer, burning of crop residues and crop rotation are helpful to tide over the disease and pest problem. The crop can be harvested after 5-6 months.Properties and activity: The medicinal property of Coleus amboinicus is attributed to codeine, carvacrol, flavones, aromatic acids and tannins present in the plant. The essential oil from the plant contains carvacrol, ethyl salicylate, thymol, eugenol and chavicol. Leaves also contain cirsimaritin, -sitosterol- -D-glucoside and oxalacetic acid. Leaves are bitter, acrid, thermogenic, aromatic, anodyne, appetising, digestive, carminative, stomachic, anthelmintic, constipating, deodorant, expectorant, diuretic and liver tonic.Coleus vettiveroides is bitter, cooling, diuretic, trichogenous and antipyretic.Coleus forskohlii roots are rich in diterpenoids like forskolin, coleonols, coleons, barbatusin, cyclobutatusin, coleosol, coleol, coleonone, deoxycoleonol, 7-deacetylforskolin and 6-acetyl-7-deacetylforskolin. Its root is spasmolytic, CNS active, hypothermic and diuretic. Forskolin is bronchodialative and hypotensive (Hussain et al,1992). Forskolin is also useful in preventing the clotting of blood platelets, in reducing intraocular pressure in glaucoma and as an aid to nerve regeneration following trauma (Sharma, 1998)... coleusSerum is a clear, yellowish ?uid containing around 7 per cent proteins and globulins, small quantities of salts, fat, sugar, urea, and uric acid, and even smaller quantities of immunoglobulins, essential in the prevention of disease (see IMMUNITY; IMMUNOLOGY). The serum given in the commonly used vaccines is generally derived from horses’ blood, after they have been subjected to a long course of treatment.... serum
The disorder may, however, occur for no obvious reason and is then called polycythaemia vera. This type develops mainly in people over 40 and about 400 people develop the disorder every year in the United Kingdom. The blood thickens, the sufferer may develop high blood pressure, ?ushing, headaches, itching and an enlarged spleen. A stroke may occur later in the disease process. Treatment of polycythaemia vera is by regular removal of blood by VENESECTION, sometimes in combination with an anticancer drug. Secondary polycythaemia is treated by remedying the underlying cause.
Polycythaemia rubra vera A disorder in which the red blood cells increase in number along with an increase in the number of white blood cells and platelets. The cause is unknown. Severe cases may require treatment with CYTOTOXIC drugs or RADIOTHERAPY.... polycythaemia
Position and size The spleen lies behind the stomach, high up on the left side of the abdomen, and corresponds to the position of the ninth, tenth and 11th ribs, from which it is separated by the diaphragm. It is a soft, highly vascular, plum-coloured organ, and has a smooth surface. It is usually about 12·5–15 cm (5–6 inches) in length, and weighs about 170 grams or more. In diseased conditions the organ may reach a weight of 8–9 kg.
Structure The spleen is enveloped by peritoneal membrane beneath which is a strong elastic tunic, composed partly of ?brous tissue
containing many elastic ?bres, and partly of unstriped muscle. This elastic coat allows of the free expansion and contraction of the organ according to the varying amount of blood present in it. From the inner surface of the membrane, ?brous partitions known as trabeculae run down into the substance and form a network in which the dark spleen pulp is contained. The pulp consists of delicate connective-tissue ?bres passing between the various trabeculae, and of white and red blood cells lying in this meshwork. The spleen is very vascular and venous blood leaves by the splenic vein and then enters the portal vein from the liver. There are also numerous lymphatics in the organ, which run in the trabeculae or surround the veins.
Functions The organ produces lymphocytes (see LYMPHOCYTE) and acts as a reservoir of red blood cells for use in emergencies. It is also one of the sites for the manufacture of red blood cells in the fetus, but not after birth. Useless or worn-out red and white blood cells and blood PLATELETS are broken up by this organ. This results in the production of BILIRUBIN, which is conveyed to the liver, and of iron, which is used in the bone marrow for the production of new red blood cells.... spleen
Thrombosis may occur in the vessels of the brain and thus causes STROKE in people whose arteries are much diseased.
Thrombosis of a coronary artery of the heart is a very serious condition which affects, as a rule, middle-aged or elderly people.
(See also ARTERIES, DISEASES OF; COAGULATION; HEART, DISEASES OF – Coronary thrombosis; VEINS, DISEASES OF.)... thrombosis
Bayberry, Cowslip root (Biostrath), Garlic, Ginseng, Lime flowers. ... anti-coagulants
Causes Blood supply to the brain may be interrupted by arteries furring up with ATHEROSCLEROSIS (which is accelerated by HYPERTENSION and DIABETES MELLITUS, both of which are associated with a higher incidence of strokes) or being occluded by blood clots arising from distant organs such as infected heart valves or larger clots in the heart (see BLOOD CLOT; THROMBOSIS). Hearts with an irregular rhythm are especially prone to develop clots. Patients with thick or viscous blood, clotting disorders or those with in?amed arteries – for example, in SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) – are particularly in danger of having strokes. Bleeding into the brain arises from areas of weakened blood vessels, many of which may be congenital.
Symptoms Minor episodes due to temporary lack of blood supply and oxygen (called TRANSIENT ISCHAEMIC ATTACKS OR EPISODES (TIA, TIE)) are manifested by short-lived weakness or numbness in an arm or leg and may precede a major stroke. Strokes cause sudden weakness or complete paralysis of the muscles controlled by the part of the brain affected, as well as sensory changes (e.g. numbness or tingling). In the worst cases these symptoms and signs may be accompanied by loss of consciousness. If the stroke affects the area of the brain controlling the larynx and throat, the patient may suffer slurring or loss of speech with di?culty in initiating swallowing. When the face is involved, the mouth may droop and the patient dribble. Strokes caused by haemorrhage may be preceded by headaches. Rarely, CVAs are complicated by epileptic ?ts (see EPILEPSY). If, on the other hand, numerous small clots develop in the brain rather than one major event, this may manifest itself as a gradual deterioration in the patient’s mental function, leading to DEMENTIA.
Investigations Tests on the heart or COMPUTED TOMOGRAPHY or ultrasonic scans (see ULTRASOUND) on arteries in the neck may indicate the original sites of distantly arising clots. Blood tests may show increased thickness or tendency to clotting, and the diagnosis of general medical conditions can explain the presence of in?amed arteries which are prone to block. Special brain X-rays show the position and size of the damaged brain tissue and can usually distinguish between a clot or infarct and a rupture of and haemorrhage from a blood vessel in the brain.
Management It is better to prevent a stroke than try to cure it. The control of a person’s diabetes or high blood pressure will reduce the risk of a stroke. Treatment with ANTICOAGULANTS prevents the formation of clots; regular small doses of aspirin stop platelets clumping together to form plugs in blood vessels. Both treatments reduce the likelihood of minor transient ischaemic episodes proceeding to a major stroke.
Once the latter has occurred, there is no e?ective treatment to reduce the damage to brain tissue. Function will return to the affected part of the body only if and when the brain recovers and messages are again sent down the appropriate nerves. Simple movements are more likely to recover than delicate ones, and sophisticated functions have the worst outlook. Thus, movement of the thigh may improve more easily than ?ne movements of ?ngers, and any speech impairment is more likely to be permanent. A rehabilitation team can help to compensate for any disabilities the subject may have. Physiotherapists maintain muscle tone and joint ?exibility, whilst waiting for power to return; occupational therapists advise about functional problems and supply equipment to help patients overcome their disabilities; and speech therapists help with diffculties in swallowing, improve the clarity of remaining speech or o?er alternative methods of communication. District nurses or home helps can provide support to those caring for victims of stroke at home. Advice about strokes may be obtained from the Stroke Association.... stroke
Possibility of mercurial poisoning. A 59-year-old man employed filling thermometers with mercury developed aplastic anaemia and died. His urine contained 1.01mg mercury per litre. (D.R. Ryrie. Brit. Medical Journal, i/1970, 499. A similar report D.R. Wilson, ibid., ii/1966, 1534)
Symptoms. Headache, dizziness, pallor of skin, loss of weight and appetite, sore or burning tongue, jaundice, bruising, nose-bleeds. A low state of the immune system exposes the subject to infection. Treatment. Hospital supervision. Necessary to identify the causative toxic agent and eliminate it. Condition fails to respond to usual preparations of iron taken by mouth. No specific exists but supportive adaptogen herbs sustain and raise haemoglobin levels, marginally increasing red cells.
To facilitate elimination of toxic chemicals:– Teas: Alfalfa, Red Clover, German Chamomile, Ground Ivy, Milk Thistle, Gotu Kola, Nettles, Fennel.
Tea. Formula. Equal parts: Dandelion, Nettles, Alfalfa. 1 heaped teaspoon in each cup boiling water, infuse 10-15 minutes. One cup freely.
Decoction: Gentian – 1 teaspoon in cup cold water. Steep overnight; drink on rising.
Tinctures. To stimulate bone marrow. Formula: equal parts, Echinacea, Prickly Ash bark, Horsetail. Dose: 1-2 teaspoons thrice daily, taken in water or cup of one of the above teas.
Tincture Cinnamon BP (1949). Dose: 2-4ml (30-60 drops).
Powders. Combine: Gentian 1; Yellow Dock 1; Echinacea 2; Cinnamon quarter; Cayenne quarter. Dose: 500mg (two 00 capsules or one-third teaspoon), before meals.
Liquid Extracts: Combine Echinacea 2; Black Cohosh half; Damiana 1; Ginger quarter. Dose: 1 teaspoon in cup Red Clover tea, before meals.
Diet. Dandelion coffee, high fibre, low fat, low salt, molasses, lamb’s liver. Foods containing Vitamin B12.
Supplements daily. Vitamin B12. Folic acid 400mcg, Vitamin C, Floradix. ... anaemia: aplastic
mm of blood.
The proportion of various white blood cells is measured and the size and shape of red and white cells is noted.
It is the most commonly performed blood test and is important for diagnosing anaemia or confirming the presence of an infection to which the blood has responded.
It is also used to diagnose disorders such as leukaemia and thrombocytopenia.... blood count
Transfusion of blood is a technique that has been used since the 17th century – although, until the 20th century, with a subsequent high mortality rate. It was only when incompatibility of BLOOD GROUPS was considered as a potential cause of this high mortality that routine blood-testing became standard practice. Since the National Blood Transfusion Service was started in the United Kingdom (in 1946), blood for transfusion has been collected from voluntary, unpaid donors: this is screened for infections such as SYPHILIS, HIV, HEPATITIS and nvCJD (see CREUTZFELDT-JAKOB DISEASE (CJD)), sorted by group, and stored in blood-banks throughout the country.
In the UK in 2004, the National Blood Authority – today’s transfusion service – announced that it would no longer accept donations from anyone who had received a blood transfusion since 1980 – because of the remote possibility that they might have been infected with the PRION which causes nvCJD.
A standard transfusion bottle has been developed, and whole blood may be stored at 2–6 °C for three weeks before use. Transfusions may then be given of whole blood, plasma, blood cells, or PLATELETS, as appropriate. Stored in the dried form at 4–21 °C, away from direct sunlight, human plasma is stable for ?ve years and is easily reconstituted by adding sterile distilled water.
The National Blood Authority prepares several components from each donated unit of blood: whole blood is rarely used in adults. This permits each product, whether plasma or various red-cell concentrates, to be stored under ideal conditions and used in appropriate clinical circumstances – say, to restore blood loss or to treat haemostatic disorders.
Transfusion of blood products can cause complications. Around 5 per cent of transfused patients suffer from a reaction; most are mild, but they can be severe and occasionally fatal. It can be di?cult to distinguish a transfusion reaction from symptoms of the condition being treated, but the safe course is to stop the transfusion and start appropriate investigation.
In the developed world, clinicians can expect to have access to high-quality blood products, with the responsibility of providing blood resting with a specially organised transfusion service. The cause of most fatal haemolytic transfusion reactions is a clerical error due to faulty labelling and/or failure to identify the recipient correctly. Hospitals should have a strict protocol to prevent such errors.
Arti?cial blood Transfusion with blood from donors is facing increasing problems. Demand is rising; suitable blood donors are becoming harder to attract; the processes of taking, storing and cross-matching donor blood are time-consuming and expensive; the shelf-life is six weeks; and the risk of adverse reactions or infection from transfused blood, although small, is always present. Arti?cial blood would largely overcome these drawbacks. Several companies in North America are now preparing this: one product uses puri?ed HAEMOGLOBIN from humans and another from cows. These provide oxygen-carrying capacity, are unlikely to be infectious and do not provoke immunological rejections. Yet another product, called Oxygene®, does not contain any animal or human blood products; it comprises salt water and a substance called per?ubron, the molecules of which store oxygen and absorb carbon dioxide more e?ectively than does haemoglobin. Within 24 hours of being transfused into a person’s bloodstream, per?ubron evaporates and is harmlessly breathed out by the recipient. Arti?cial blood is especially valuable in that it contains no unwanted proteins that can provoke adverse immunological reactions. Furthermore, it is disease-free, lasts for up to three years and is no more expensive than donor blood. It could well take the place of donor blood within a few years.
Autologous transfusion is the use of an individual’s own blood, provided in advance, for transfusion during or after a surgical operation. This is a valuable procedure for operations that may require large transfusions or where a person has a rare blood group. Its use has increased for several reasons:
fear of infection such as HIV and hepatitis.
shortages of donor blood and the rising cost of units of blood.
substantial reduction of risk of incompatible transfusions. In practice, blood transfusion in the UK is
remarkably safe, but there is always room for improvement. So, in the 1990s, a UK inquiry on the Serious Hazards of Transfusion (SHOT) was launched. It established (1998) that of 169 recently reported serious hazards following blood transfusion, 81 had involved a blood component being given to the wrong patient, while only eight were the result of viral or bacterial infections.
There are three ways to use a patient’s own blood in transfusion:
(1) predeposit autologous donation (PAD) – taking blood from a patient before operation and transfusing this blood back into the patient as required during and after operation.
(2) acute normovalaemic haemodilution (ANH) – diluting previously withdrawn blood and thus increasing the volume before transfusion.
(3) perioperative cell salvage (PCS) – the use of centrifugal cell separation on blood saved during an operation, particularly spinal surgery where blood loss may be considerable.
The government has urged NHS trusts to consider the introduction of PCS as a possible adjunct or alternative to banked-blood transfusion. In one centre (Nottingham), PCS has been used in the form of continuous autologous transfusion for several years with success.
Exchange transfusion is the method of treatment in severe cases of HAEMOLYTIC DISEASE OF THE NEWBORN. It consists of replacing the whole of the baby’s blood with Rh-negative blood of the correct blood group for the baby.... transfusion
Habitat: Kashmir at 1,200-2,400 m.
English: Pale Wood Violet, Wood Violet.Unani: Banafashaa (related species).Action: Plant—pectoral, bechic; used in chest troubles. Stem, leaf and flower—applied to foul sores and wounds.
Habitat: Native to Europe; grown as an ornamental.
English: Heartsease, Wild Pansy.Unani: Banafashaa (related species).Action: Herb—anti-inflammatory, antiallergic, expectorant, diuretic, antirheumatic, alterative. Used for bronchitis, rheumatism, chronic skin disorders and for preventing capillary haemorrhage when under corticosteroid therapy. Root— antidysenteric; used as a substitute for Cephaelis ipecacuanha.
Key application: Externally in mild seborrheic skin diseases and milk scall in children. (German Commission E.) The British Herbal Pharmacopoeia recognizes the herb as an expectorant and dermatological agent.The herb contains rutin, violin and salicylic acid. The flower contains rutin, quercetin, violanthin (6,8-digly- coside of apigenin), violaxanthin, p- hydroxycinnamic acid and delphini- din. A flavone C-glycoside-saponarin has also been obtained from flowers. Flowers, in addition, contain 15-cis- violaxanthin.The herb exhibits anticoagulant property and diminishes the aggregation of platelets. It can be used as a preventive measure against thrombosis.Habitat: Temperate Himalayas from Kashmir to Nepal between 1,200 and 2,700 m (a semiparasitic plant).
English: European Mistletoe.Ayurvedic: Bandaaka, Suvarna- bandaaka. Vrikshaadani (substitute).Unani: Kishmish Kaabuli.Action: Vasodilator, cardiac depressant, tranquiliser, stimulates the vagus nerve which slows the pulse, anti-inflammatory, diuretic, immune enhancer, antineoplas- tic. Used for hypertension and tachycardia, as a nervine tonic.
The extract of leafy twigs is anti- inflammatory exerting an action upon capillary permeability and oedema. It stimulates granulation and the neoformation of connective tissue.Key application: For treating degenerative inflammation of the joints by stimulating cuti- visceral reflexes following local inflammation brought about by intradermal injections; as palliative therapy for malignant tumour through non-specific stimulation. (German Commission E.)Mistletoe contains glycoproteins; flavonoids, usually quercetin-derived (dependent on host tree to some extent); polypeptides; phenylcarboxylic acids; polysaccharides (including viscid acid); alkaloids; lignans.Cardiotonic activity is due to the lig- nans. The polysaccharides stimulate the immune response. Antineoplas- tic activity is claimed to be responsible for prolongation of survival time in cancer patients. Polypeptides (visco- toxins) inhibit tumours and stimulate immune resistance. (For uses of lectin from Mistletoe in cancer, see Eur J cancer, 2001, Jan, 37(1), 23-31; Eur J Cancer 2001, 37 (15), 19101920.) (For application in hepatitis, see Fitoterapia, 70, 2001.)... viola sylvestrisA dissolved protein called fibrinogen is converted to fibrin, which forms long filaments that bind clumps of platelets and other blood cells into a mass which plugs the bleeding point.... fibrin
injury. First, small blood vessels constrict. Second, small blood cells called platelets aggregate and plug the bleeding points. Third, the plasma coagulates, forming filaments of a substance called fibrin, which help to seal the damaged blood vessel (see blood clotting). Defects in any of these mechanisms can cause a bleeding disorder.... haemostasis
EFA deficiency may be caused by alcohol, particularly Omega-6. Deficiencies may be responsible for a wide range of symptoms from foul-smelling perspiration to psoriasis, pre-menstrual tension and colic. EFAs are precursors of prostaglandin formation.
EFAs are present in oily fish and reduce the adhesion of platelets and the risk of heart disease. They reduce blood cholesterol and increase HDLs.
Common sources: cold pressed seeds, pulses, nuts and nut oils. Evening Primrose oil (15-20 drops daily). The best known source is Cod Liver oil (1-8 teaspoons daily); (children 1 teaspoon daily to strengthen immune system against infection); bottled oil preferred before capsules. To increase palatability pour oil into honey jar half filled with orange or other fruit juice, shake well and drink from the jar.
Margarines, salad dressings, cooking and other refined vegetable oils inhibit complete absorption of EFAs and should be avoided. EFAs require the presence of adequate supply of Vitamins A, B, C, D, E and minerals Calcium, Iron, Magnesium and Selenium. ... essential fatty acids (efa)
Constituents: sesquiterpene lactones, volatile oil, parthenolides.
Action: Anti-migraine, anti-rheumatic, febrifuge, bitter, carminative, tranquilliser, diuretic, antispasmodic, laxative, vermifuge. Anti-thrombotic (inhibits deposition of platelets). Vasodilator. Anti- inflammatory.
Uses: Protection against clot formation. Meniere’s disease, vertigo; painful, absent or irregular menstruation, threatened miscarriage, psoriasis. Inflammatory rheumatism, arthritis. After 12 years with osteo-arthritis of the hands, a patient ate 3 leaves a day and was soon able to turn most taps without a tapeze.
Migraine preventative. Dr John Hill (Hill’s Family Herbal, 1808) recommended it for violent headache and as an antidote for mercurial poisoning. In psychosomatic medicine for depression or hysteria due to menstrual disorders. Especially effective for migraine relieved by hot packs. Preparations. The herb is said to be less effective when subjected to heat, hence its popular use as the fresh leaf, powder, tincture or essence prepared ‘cold’.
Fresh leaves. 1 or 2 large or 3 or 4 small, every day until positive results achieved. If too acrid, may be eaten with bread in a sandwich or in mashed banana. 125mg of the leaf provides 0.2 per cent parthenolides which a Canadian authority regards as a minimum dose.
Tablets. One 125ml tablet or capsule is equivalent to 2 leaves daily.
Tincture. The tincture best captures its therapeutic properties where laid down within 2 hours of harvesting. To prepare: 1 part pulp Feverfew leaves (fresh) to 5 parts 45 per cent alcohol. Macerate 7 days. Filter. Dose: 5-20 drops every 2 hours for acute conditions; thrice daily, chronic.
Liquid Extract. Dose: 3-15 drops.
Poultice. Crushed leaves for aching muscles and joints. Suppositories. For piles.
Allergic effects (rare). Mouth ulcer, sore tongue, skin rash.
Not used in pregnancy or by women on the contraceptive pill.
Note: Extracts and products should be kept out of a bright light and stored below room temperature. Roots and stalks are of no value. (Dr S. Heptinstall, Nottingham University Medical School) ... feverfew
Onset: diarrhoea with streaks of blood, vomiting, breathlessness, feverishness, dizziness, jaundice and enlargement of the spleen.
Other causes may be mismatched food transfusion, environmental chemicals, nitrite food preservatives and analgesic drugs.
Alternatives. Tea. Combine herbs: Red Clover (to increase platelets) 3; Yarrow (kidneys) 2; Hops (cerebrospinal supportive) 1. 1-2 teaspoons to each cup boiling water; infuse 15 minutes. Half-1 cup freely.
Formula: Combine, Tinctures. Red Clover 2; Fringe Tree 1; Hops half. Dose: one 5ml teaspoon. Babies: 2 drops in feed; infants 3-5 years 10 drops in water and honey thrice daily.
Supplementation. Vitamin B-complex. C.
To be treated by or in liaison with a qualified medical practitioner. ... haemolytic-uraemia syndrome (hus)
Causes. Diet of too much animal fat, smoking, overweight, little exercise.
Symptoms. Same as those for ischaemic heart disease, acute pancreatitis, indigestion, abdominal pain. Alternatives. Hawthorn berries, Lime flowers, Goat’s Rue. Garlic – raw bulb with salads or 2-3 capsules at night. Herb Purslane (Portulaca oleracae): rich in EFA’s (essential fatty acids) in general, and EPA in particular.
Garlic powder significantly reduces serum cholesterol and triglyceride levels in hyperlipidaemia. (German Association of General Practitioners, Study Group on Phytotherapy)
Guar gum. Lowers serum fat levels, body weight and blood pressure: see entry. Add Hawthorn for angina; Goat’s Rue for diabetes; Ispaghula seeds (Regulan) for intestinal and bowel health and to reduce blood-fats.
Fenugreek seeds. Lowers blood cholesterol levels in healthy people and in diabetics. Contain galacto- mannan which aids fat digestion.
Diet. Low fat. High-complex carbohydrate diet. Sugar and refined starches raise but Oats and Bran lower cholesterol levels. High levels reduced by oleic acid (Olive oil). French research workers claim three apples a day can lower plasma and liver cholesterol levels by as much as 30 per cent. The effect is believed to be due to vegetable fibre, especially pectin. Those who stopped eating their three apples after the trial showed a return to higher levels. Replace unsaturated with vegetable polyunsaturated fats. Two or three fatty fish meals weekly to prevent clumping of platelets. Linseed, Grape juice, Artichokes. See entry – OILY FISH.
Supplement: Nicotinic acid.
Stop smoking. Limit intake of alcohol. ... hyperlipidaemia
Treatment of cancer with radiotherapy or anticancer drugs can temporarily interfere with the cell-producing ability of bone marrow, as can certain viral infections and other drugs. Long-term exposure to insecticides or benzene fumes may cause more persistent aplastic anaemia, and a moderate to high dose of nuclear radiation is another recognized cause. An autoimmune disorder is responsible in about half of all cases. Aplastic anaemia sometimes develops for no known reason.
A low level of red blood cells may cause symptoms common to all types of anaemia, such as fatigue and breathlessness. White-cell deficiency increases susceptibility to infections; platelet deficiency may lead to a tendency to bruise easily, bleeding gums, and nosebleeds.
The disorder is usually suspected from blood-test results, particularly a blood count, and is confirmed by a bone marrow biopsy.
Blood and platelet transfusions can control symptoms.
Immunosuppression is used to treat anaemia due to an autoimmune process.
Severe persistent aplastic anaemia may be fatal unless a bone marrow transplant is carried out.... anaemia, aplastic
Aspirin is not usually given to children because there is a slight risk of Reye’s syndrome (a rare brain and liver disorder) developing. Aspirin may cause irritation of the stomach lining, resulting in indigestion or nausea. Prolonged use may cause bleeding from the stomach due to gastric erosion or peptic ulcer.... aspirin
Coagulation disorders are usually due a deficiency of or abnormality in the enzymes (coagulation factors) involved in blood clotting. Defects may be congenital or acquired later in life. The
main congenital coagulation defects are von Willebrand’s disease, haemophilia, and Christmas disease.
Acquired defects of coagulation factors may develop at any age due to severe liver disease, digestive system disorders that prevent the absorption of vitamin K (needed to make certain coagulation factors), or the use of anticoagulant drugs. Disseminated intravascular coagulation (DIC) is an acquired disorder that is both complex and serious. It may be the result of underlying infection or cancer. In this condition, platelets accumulate and clots form within small blood vessels; coagulation factors are used up faster than they can be replaced, and severe bleeding may result.
Coagulation disorders are treated by replacement of the missing factor, factors extracted from fresh blood, or fresh frozen plasma. Genetically engineered factors may be used. Anticoagulants are sometimes used to suppress excess clotting activity in.
Thrombocytopenia, which results from insufficient platelets in the blood, produces surface bleeding into the skin and gums and multiple small bruises. Platelet defects may be inherited, associated with the use of certain drugs (including aspirin), or a complication of certain bone marrow disorders such as myeloid leukaemia. Treatment consists of platelet transfusions. Rarely, abnormal bleeding is caused by a bloodvessel defect or scurvy. Elderly people and patients on long-term courses of corticosteroid drugs may suffer mild abnormal bruising due to loss of skin support to the smallest blood vessels.
Treatment is rarely required.... bleeding disorders
There are usually no symptoms in the early stages of atherosclerosis. Later, symptoms are caused by reduced or total absence of a blood supply to the organs supplied by the affected arteries. If the coronary arteries, which supply the heart muscle, are partially blocked, symptoms may include the chest pain of angina. If there is complete blockage in a coronary artery, a sudden, often fatal, heart attack may occur. Many strokes are a result of atherosclerosis in the arteries that supply blood to the brain. If atherosclerosis affects the leg arteries, the 1st symptom may be cramping pain when walking due to poor blood flow to the leg muscles. If the condition is associated with an inherited lipid disorder (see hyperlipidaemias), fatty deposits may develop on tendons or under the skin in visible lumps.
The risk of developing atherosclerosis is determined largely by the level of cholesterol in the bloodstream, which depends on dietary and genetic factors. Athersclerosis is most common in Western countries, where most people eat a diet high in fat. Some disorders such as diabetes mellitus can be associated with a high cholesterol level regardless of diet. Blood flow through an artery can be investigated by angiography or Doppler ultrasound scanning.
The best treatment for atherosclerosis is to prevent it from progressing by following a healthy lifestyle. This includes eating a low-fat diet, not smoking, exercising regularly, and maintaining the recommended weight for height. These measures lead to a lower-than-average risk of developing significant atherosclerosis. People found to have high blood cholesterol but who are otherwise in good health will be advised to adopt a low-fat diet. They may also be given drugs that decrease blood cholesterol levels (see lipid-lowering drugs). For people who have had a heart attack, research has shown that there may be a benefit in lowering blood cholesterol levels, even if the level is within the average range for healthy people.
People who have atherosclerosis and are experiencing symptoms of the condition may be prescribed a drug such as aspirin to reduce the risk of blood clots forming on the damaged artery lining.
Surgical treatment such as coronary angioplasty (see angioplasty, balloon) may be recommended for those people thought to be at high risk of severe complications. If blood flow to the heart is severely obstructed, a coronary bypass operation to restore blood flow may be carried out.... atherosclerosis
Red blood cells (also known as RBCs, red blood corpuscles, or erythrocytes) transport oxygen from the lungs to the tissues (see respiration). Each is packed with haemoglobin, enzymes, minerals, and sugars. Abnormalities can occur in the rate at which RBCs are either produced or destroyed, in their numbers, and in their shape, size, and haemoglobin content, causing forms of
anaemia and polycythaemia (see blood, disorders of).
White blood cells (also called WBCs, white blood corpuscles, or leukocytes) protect the body against infection and fight infection when it occurs. The 3 main types of are granulocytes (also called polymorphonuclear leukocytes), monocytes, and lymphocytes. Granulocytes are further classified as neutrophils, eosinophils, or basophils, and each type of granulocyte has a role in either fighting infection or in inflammatory or allergic reactions. Monocytes and lymphocytes also play an important part in the immune system. Lymphocytes are usually formed in the lymph nodes. One type, a T-lymphocyte, is responsible for the delayed hypersensitivity reactions
White (see allergy) and Red blood blood cell is also involved in cell (neutrophil) protection against cancer. T-lymphocytes manufacture chemicals, known as lymphokines, which affect the function of other cells. In addition, the T-cells moderate the activity of B-lymphocytes, which form the antibodies that can prevent a second attack of certain infectious diseases. Platelets (also known as thrombocytes), are the smallest blood cells and are important in blood clotting.
The numbers, shapes, and appearance of the various types of blood cell are of great value in the diagnosis of disease (see blood count; blood film).... blood cells
When a blood vessel is damaged, it constricts immediately to reduce blood flow to the area. The damage sets off a series of chemical reactions that lead to the formation of a clot to seal the injury. First, platelets around the injury site are activated, becoming sticky and adhering to the blood-vessel wall. Then, the activated platelets release chemicals, which, in turn, activate blood clotting factors. These factors, together with vitamin K, act on fibrinogen and convert it to fibrin. Strands of fibrin form a meshwork, which traps red blood cells to form a clot.
There are several anticlotting mechanisms to prevent the formation of unwanted clots. These include prostacyclin (a prostaglandin), which prevents platelet aggregation, and plasmin, which breaks down fibrin (see fibrinolysis). Blood flow washes away active coagulation factors; and the liver deactivates excess coagulation factors.
Defects in blood clotting may result in bleeding disorders.
Excessive clotting (thrombosis) may be due to an inherited increase or defect in a coagulation factor (see factor V), the use of oral contraceptives, a decrease in the level of enzymes that inhibit coagulation, or sluggish blood flow through a particular area.
Treatment is usually with anticoagulant drugs such as heparin or warfarin.... blood clotting
Donated blood is tested for a range of infectious agents such as hepatitis B and hepatitis C and antibodies to HIV. After being classified into blood groups, the blood is stored in a blood bank, either whole or separated into its different components (see blood products). Apheresis is a type of blood donation in which only a specific blood component, such as plasma, platelets, or white cells, is withdrawn from the donor. blood film A test that involves smearing a drop of blood on to a glass slide for examination under a microscope. The blood film is stained with dyes to make the blood cells show up clearly.
The test allows the shape and appearance of blood cells to be checked for any abnormality, such as the sickleshaped red blood cells characteristic of sickle cell anaemia.
The relative proportions of the different types of white blood cells can also be counted.
This examination, called a differential white cell count, may be helpful in diagnosing infection or leukaemia.
Blood films are also used in diagnosing infections, such as malaria, in which the parasites can be seen inside the red blood cells.
Blood films are usually carried out together with a full blood count.... blood donation
Platelets may be given in transfusions for people with blood-clotting disorders. Patients who have life-threatening infections may be treated with granulocytes, a type of white blood cell. Fresh frozen plasma is used to correct many types of bleeding disorder because it contains all the clotting factors. Albumin, prepared from the plasma of whole blood, is used mainly to treat shock resulting from severe blood loss until compatible whole blood becomes available. Purified albumin preparations are used to treat nephrotic syndrome and chronic liver disease.
Concentrates of blood clotting factors and are used in the treatment of haemophilia and Christmas disease.
Immunoglobulins (also called antibodies), which are extracted from blood plasma, can be given by injection (see immunoglobulin injection) to protect people who are unable to produce their own antibodies or have already been exposed to an infectious agent, or to provide short-term protection against hepatitis A.
Immunoglobulins are given in large doses to treat certain autoimmune disorders.... blood products
TIPSS (transjugular intrahepatic porto-systemic shunt) see portal hypertension.... tioguanine
Careful monitoring of blood pressure and proteinuria throughout pregnancy ensures prompt treatment of impending eclampsia.
Immediate delivery, often by caesarian section, together with antihypertensive and anticonvulsant drugs is needed.
Patients may need intensive care to prevent the development of complications such as kidney failure.
Blood pressure often returns to normal in the months after delivery, but it may remain high.
There is a risk of recurrence in subsequent pregnancies.... eclampsia
Exposure to certain chemicals (such as benzene and some anticancer drugs) or high levels of radiation may be a cause in some cases. Inherited factors may also play a part; there is increased incidence in people with certain genetic disorders (such as Fanconi’s anaemia) and chromosomal abnormalities (such as Down’s syndrome). People with blood disorders such as chronic myeloid leukaemia (see leukaemia, chronic myeloid) and primary polycythaemia are at increased risk, as their bone marrow is already abnormal.
The symptoms and signs of acute leukaemia include bleeding gums, easy bruising, headache, bone pain, enlarged lymph nodes, and symptoms of anaemia, such as tiredness, pallor, and breathlessness on exertion. There may also be repeated chest or throat infections. The diagnosis is based on a bone marrow biopsy. Treatment includes transfusions of blood and platelets, the use of anticancer drugs, and possibly radiotherapy. A bone marrow transplant may also be required. The outlook depends on the type of leukaemia and the age of the patient. Chemotherapy has increased success rates and 6 in 10 children with the disease can now be cured, although treatment is less likely to be completely successful in adults.... leukaemia, acute
The disease is diagnosed by bloodclotting tests and measurement of blood levels of von Willebrand factor. Bleeding episodes can be prevented or controlled by desmopressin (a substance resembling ADH). Factor or concentrated von Willebrand factor may also be used to treat bleeding.... von willebrand’s disease
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