【正文】 thargy, disorder of consciousness, a. (4) Changes of osseous system Renal rickets腎性佝僂病 , osteomalacia骨軟化癥 4) Laboratory findings ↓pH, ↓HCO3, ↓ PaCO2 if there is pensation of respiratory system. Case study: Arterial blood: pH PaCO2 26 mmHg PaO2 108 mmHg HCO3 12 mmol/L Na+ 135 mmol/L K+ mmol/L Cl 110 mmol/L Urine: pH (1) A 36yearold man was hospitalized with a 3day history of fever and watery diarrhea. The blood pressure is 90/60 mmHg, the pulse is 112/minute, the respiratory rate is 24/minute, and the temperature is . The laboratory results were obtained. 2. Respiratory acidosis 1) Concept: Respiratory acidosis is defined as a decrease of pH induced by primary increase in plasma [H2CO3]. 2) Causes Respiratory acidosis can occur as an acute or a chronic disorder. (1) Acute respiratory acidosis . acute respiratory infections, chest injuries, pulmonary edema. (2) Chronic respiratory acidosis . chronic obstructive lung disease, chronic bronchitis. 3) Compensation: Buffer system and cell 4) Manifestations: Headache, cardiac arrhythmias and neurologic abnormalities. Neurologic manifestations may be more prominent in respiratory acidosis than in metabolic acidosis. ―CO2 narcosis‖ The mechanism: (1) CO2 crosses the bloodbrain barrier relatively easily, and can dilate the blood vessels in the brain and lead to brain edema. (2) CO2 can also decrease the pH of the cerebrospinal fluid, and make depression of neural function, like weakness, confusion, paralysis, stupor and a. 5) Laboratory findings ↓pH, ↑ PaCO2, ↑HCO3 if there is pensation of kidneys (chronic). 3. Metabolic alkalosis 1) Concept: Metabolic alkalosis refers to a primary increase in base bicarbonate, the pH elevates. 2) Causes: (1) Decrease of acid . vomiting (Ileus: intestinal obstruction). (2) Increase of base . antacids, transfusion with citrated blood, hyperaldosteronism. Salineresponsive alkalosis and salineresistant alkalosis 3) Compensation 4) Manifestations Alkalosis can cause increased excitability of nervous system, like hyperactive reflexes, muscle hypertonicity, tetany etc. 5) Laboratory findings ↑pH, ↑HCO3, ↑ PaCO2 if there is pensation of respiratory system. 4. Respiratory alkalosis 1) Concept: Respiratory alkalosis is defined as an increase of pH induced by primary decrease in plasma [H2CO3]. 2) Causes: Hyperventilation . anxiety, hysteria, fever, early salicylate (aspirin) toxicity, misuse of mechanical ventilation. 3) Compensation 4) Manifestations Tetany 5) Laboratory findings ↑pH, ↓PaCO2, ↓HCO3 (depend on the normal renal function). 5. Mixed acidbase imbalances Concept: Two or more primary acidbase imbalances exist at the same time. Bacterial pneumonia→ respiratory acidosis Patient Diarrhea→ metabolic acidosis In this mixed imbalance, the pH is likely to be very low. Pneumonia→ respiratory acidosis Patient Vomiting→ metabolic alkalosis In this mixed imbalance, the pH will change slightly or in normal range. Acidosis + acidosis, or alkalosis + alkalosis, the pH will change a lot。 diarrhe