Chemical Composition of Blood Plasma Terms. Mechanics of investigation. High- and low- MW compounds of bl.pl. Interpretation of investigations in clinical practice: –“Basic set” – Disorders of the kidneys and internal environment –Inflammation –Liver disorders

Serum = liquid remaining after clotting – usefull for most biochem. tests Plasma = whole blood - cells – emergency tests –small samples (yield is greater) –clotting tests The mechanics of investigations – Blood collection: venepuncture Basic terms and mechanics of investigation

Biochemical abnormalities are important markers of disease Diagnosis = history + examination + biochemical tests + imaging techniques Treatment: monitoring of the response to therapy in both acute and chronic disorders Prognosis and secondary prevention Screening: detecting the non-apparent disease, eg. PKU or hypothyreosis

Low-molecular weight compounds of blood plasma Cations: Na +, K +, Ca + + Anions: Cl -, HCO 3 -, HPO 4 2-, HSO 4 - Metabolites: urea, creatinine, uric acid, bilirubin Nutrients: glucose, FFA, ketones Other +

High MW compounds of blood plasma (= proteins) According to the function – oncotic pressure –clotting factors and fibrinolytic agents –transport: binding proteins, apoproteins –antibodies and complement: IgG, IgM –buffers –none: enzymes used for diagnostics Electrophoretic separation: prealbumin, albumin, α-, β-, γ-globulines

Internal environment and the blood buffers Basic life conditions: –isoionia: concentrations of certain ions must be kept in narrow range –isoosmia: osmotic pressure is allways the same in ECS and in cells (in dehydratation osmotic pressure rises) –isohydria: pH = Blood buffers: bicarbonate, hemoglobine, proteins and phosphate

Internal environment investigation Water metabolism: osmolality, Na + Acid-base balance disordes: “Astrup“ –taken from arterial blood –pH, pO 2, pCO 2, HCO 3 -, BE, BB, AG, lactate Kidney failure: K +, urea, creatinine, phosphate and sulphate retention Respiration failure: pO 2 decrease with/without pCO 2 increase

Inflammation History + examination Changes in the blood count (eg. leucocytosis) and sedimentation rate Non-specific inflammatory markers: eg. CRP and fibrinogen Specific antibodies: IgG or IgM (ELISA) Antigen assays: eg. HBsAg

Assays for liver and billiary tract function and disease Parenchyme damage: –increase in enyzme activity in plasma: ALT, AST, ALP, GMT Alteration of liver function: – bilirubin accumulation (jaundice) –alteration of protein synthesis: hypoalbuminaemia, clotting disturbancies

„Basic set“ Taken from most of the patients admitted to hospital Give to the physician basic overview about patient’s metabolic state and organ functions Contains : –Na, K, Cl, glycaemia –liver set: ALT, AST, bilirubin, (ALP, GMT) –kidney set: urea, kreatinine –blood count and FW –urine examination + sediment