Haemoglobin concentration

There are many causes of the clinical condition referred to as anaemia. One particular type, whose cause can be traced to a genuine metabolic defect is megaloblastic anaemia and is due to a deficiency of the vitamins B12 (cobalamin) and/or folate. These vitamins are required for normal cell division in all tissues, but the rapid production of red cells makes them more susceptible to deficiency. In megaloblastic anaemia the blood haemoglobin concentration falls the synthesis of haem is not impaired. Examination of the blood reveals the appearance of larger then normal cells called macrocytes and megaloblasts are found in the bone marrow. 

Vitamin D deficiency may also occur through inadequate dietary intake, gut (poor absorption), renal disease (1-hydroxylase deficiency or failure to reclaim calcium from the glomerular filtrate), or liver disease (25-hydroxylase deficiency). The slightly low haemoglobin concentration and pale stained (hypochromic) red cells suggested a coincident mild iron deficiency. 

The multiplier 10 is used because Cao2 is measured inml.dl-1 whereas CO is measured in l.min-1. The 02 content of the blood is calculated using a specific equation that depends mainly on haemoglobin concentration, [Hb] and saturation (Sats). 

Erythropoeitins are used to treat symptomatic anaemia associated with erythropoietin deficiency in chronic renal failure and to shorten the period of symptomatic anaemia in patients receiving cytotoxic chemotherapy. It is not recommended for use in cancer patients who are not receiving chemotherapy. In cancer patients, the risk of thrombosis and related complications might be increased. The haemoglobin concentration should be maintained within the range of 10-12 g/100 ml - higher concentrations should be avoided to reduce risk of complications of therapy. 

Bilimbin concentration in the measurement of haemoglobin concentration in human blood plasma. 

The haemoglobin concentration is not a good guide to recent blood loss because haemodilution may not have occurred. 

Haematological changes in male B6C3Fi mice exposed to 62.5, 200 or 625 ppm [138, 440 or 1380 mg/ni ] butadiene for 6 h per day on five days per week for 40 weeks included decreased red blood cell count, haemoglobin concentration and packed red cell volume and increased mean corpuscular volume. Similar changes occurred in female mice exposed to 625 ppm butadiene (for details, see Section 3.1.1) (Melnick et al., 1990). 

Q9 Both red cell number and haemoglobin concentration are reduced compared to normal values. What are the signs and symptoms of anaemia ... 

Q7 Both hypothyroidism and anaemia can cause fatigue, deficits in concentration and sleepiness. However, Zadie s haematocrit (red cell mass) is within the normal range as is her haemoglobin concentration. If Zadie were suffering from anaemia, her haemoglobin would be low and the haematocrit would be reduced. 

Q10 Adult red blood cells are produced by the bone marrow at the ends of long bones and in the pelvis, skull, ribs and sternum. In response to severe anaemia the active bone marrow in the long bones becomes more extensive. Normally, the total number of circulating red blood cells is maintained constant. Production is stimulated by the glycoprotein erythropoietin (EP), which is mainly produced by the endothelial cells of the kidney. EP production is stimulated by hypoxia and a decrease in haemoglobin concentration. EP stimulates the stem cells in bone marrow to differentiate into mature erythrocytes. 

The anaemia of chronic renal disease is due to the reduced secretion of EP by the kidney, and in renal failure red cell count and haemoglobin concentration fall considerably. 

Q9 Treatment consists of correcting the underlying cause and replacing the deficient iron. Oral administration of ferrous sulphate (containing 120-200 mg of elemental iron daily) is the standard treatment. This should be taken on an empty stomach, if tolerated, with vitamin C (ascorbic acid), which aids absorption. When the normal haemoglobin concentration in blood has been achieved, the treatment should be continued for an extra three to six months to ensure that body iron stores are replenished. 

Byrd SR, Gelber RH. Effect of dapsone on haemoglobin concentration in patients with leprosy. Lepr Rev 1991 62(2) 171-8. 

Christensson AG, Danielson BG, Lethagen SR. Normalization of haemoglobin concentration with recombinant erythropoietin has minimal effect on blood haemostasis. Nephrol Dial Transplant 2001 16(2) 313-19. 

Ducloux D, Saint-Hillier Y, Chalopin JM. Effect of losartan on haemoglobin concentration in renal transplant recipients—a retrospective analysis. Nephrol Dial Transplant 1997 12(12) 2683-6. 

At bilirubin concentrations of 0.5 mg/dl haemoglobin will produce elevated values up to haemoglobin concentration of 0.15 g/1, whereas at bilirubin concentrations of 4.8 mg/dl haemoglobin will not interfere up to 3 g/1. 

The reflectance of the dye that has formed, is measured at 535 nm during the incubation and measurement phase for a period of 45 to 180 seconds - depending upon the time until a stable reflectance value has developed (this is due to the presence of various haemoglobin derivatives). The haemoglobin concentration can be calculated by means of the calibration data obtained by a 2-point calibration (high/low). 

The effect caused by haemolysis has been estimated by referring to haemoglobin concentration. 

Complete blood count (white and red blood cell counts, differential leukocyte counts, thrombocyte counts, haemoglobin concentration, haematocrit, red cell indices) will provide information on haematological status and inflammatory conditions. 

Boyd, J. W. 1981. The relationships hetween hlood haemoglobin concentrations, packed cell volume and plasma protein concentration in dehydration. British Veterinary Journal 137 166-172. 

In spite of the poor spatial resolution, DOT in the NIR has the benefit that the measured absorption eoefficients are related to the bioehemical constitution of the tissue, sueh as haemoglobin concentration and blood oxygenation [121, 346]. If exogenous markers are used, the absorption or fluoreseence delivers additional information about blood flow, blood leakage, ion eoneentrations, or protein binding state [135, 369, 460]. 

A patient taking allopurinol 300 mg daily for gout was also given azathioprine 100 mg daily to treat autoimmune haemolytie anaemia. Within 10 weeks his platelet eount fell from 236 to 45 x (ffL, his white eell count fell from 9.4 to 0.8 x (ffL and his haemoglobin concentration fell from 11.5 to 5.3 g/dL. ... 

A situation with a similar degree of relative risk exists when the information displayed by the system is misleading but in a way that is obvions. For example, snppose a trend line showing changes in plasma haemoglobin concentration over time on one occasion dips down to a value of zero (Day 21 in Fig. 14.1) whilst all other instances of the assay appear appropriate and correct. 

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