【正文】 Respiratory acidosis and respiratory alkalosis can not exist at the same time. (2) A 32yearold male presented with vomiting of one week39。 chronic effects on heart cardiac excitability ↑ cardiac conductivity ↓ cardiac automaticity ↑ cardiac contractibility ↑ → ↓ (3). Renal polyuria (sensitivity of ADH ) (4). GI smooth muscles Hyperpolarization (5). acidbase balance metabolic alkalosis paradoxical aciduria 4. principles of prevention and treatment of primary disease of potassium pensation oral application is better Give potassium according to the urine concentration ? 40mmol/L， slowly 1020mmol/h to observe： heart rate cardiac rhythm consciousness acid base 1. definition : hyperkalemia is defined as serum potassium exceeding Ⅲ . hyperkalemia 2. causes (1). increased intake of potassium (2). Impaired renal potassium excretion ： ① renal dysfunction ② ALD ↓ ③ potassiumsparing diuretics (3). abnormal potassium transcellular ditribution ① acute acidosis ② hypoxia→ ATP ↓ ③ tissue damage ④ hyperkalemic periodic paralysis ⑤ Diabetes ⑥ Betareceptor inhibbitor 3. alterations of metabolism and function (1).effect on neuromuscular excitability: (2).effects on heart cardiac excitability ↑ → ↓ cardiac conductivity ↓ cardiac automaticity ↓ cardiac contractibility ↓ (3).effect on the acidbase balance acidosis paradoxical alkaline urine skeletal muscle ＜ 8mmol/L RP (depolarization) excitability stabbing。 tremor ＞ 8mmol/L RP inactivation of Na+ channel depolarization paralysis heart (hyperkalemia K+ permeability ) → RP → E excitability 79mmol/L→ RP → E T wave 。 ABSB, hyperventilation ③ Buffer base BB ④ Base excess BE ⑤ CO2 bine power（ CO2CP） 4) AG (anion gap): AG describes the difference between unmeasured anion (UA) and unmeasured cation (UC). AG= Na+ (Cl + HCO3). The normal range is 10 ~ 14 mmol /L (12 mmol /L). II. Acidbase imbalances 1. Metabolic acidosis 1) Concept: Metabolic acidosis refers to a primary deficit in base bicarbonate, the pH falls. 2) Causes: (1) Increase in metabolic acids ① Excess production of metabolic acids . fasting and starvation, diabetic ketoacidosis, lactic acidosis ( shock, hypoxia, heart failure, anemia). ② Decreased loss of metabolic acids . renal failure, renal tubular acidosisI ③ Over dose of acidic medicine (aspirin). AG is increased. (2) Increase in bicarbonate loss . ① Severe diarrhea, intestinal fistulas ② Renal tubular acidosisII. ③ Over dose of NH4+ ,releases HCl AG is normal. 3) Compensation: (1) Buffer system and cell (2) Signs of pensation ① Kussmaul breathing ② Acid urine 4) Manifestations (1) Heart failure: ① Hyperkalemia __cardiac arrhythmia ② Impair myocardial contraction (2) Decreased response of capillary to catecholamines __Shock (3) Depression of neural function Le