Table 1 Parameter on admission of patient 1 and 2w. Open in a separate window. Table 2 Arterial Blood Gas values. Patient 2 A year-old man with past history of hypertension and chronic renal failure was admitted to our hospital complaining of high grade fever, vomiting and diarrhoea for the past week.
Table 3 Major adverse consequences of severe alkalemia. Discussion Metabolic alkalosis has been classified traditionally as chloride responsive and chloride non responsive varieties.
The postulated causes of persistence of alkalemia and our failure to treat it adequately are: Inadequate respiratory compensation - Fever and later acute SDH probably prevented hypoventilation and compensation.
Hypoalbuminemia potentiated the alkalosis. References 1. Alkalemia-associated morbidity and mortality in medical and surgical patients. South Med J.
Metabolic alkalosis. J Intensive Care Med. Diagnosis of metabolic acid base disturbances in critically ill patients. Fencl V. Acid base disorders in critical care medicine. Annu Rev Med. Rastegar A. Clinical utility of Stewarts method in diagnosis and management of acid base disorders. Clin J Am Soc Nephrol. Strong ions, weak acids and base excess: A simplified Fencl-Stewart approach to clinical acid-base disorders.
Br J Anaesth. Validation of a method to partition the base deficit in meningococcal sepsis: A retrospective study. Crit Care. Unmeasured anions identified by the Fencl-Stewart method predict mortality better than base excess, anion gap, and lactate in patients in the pediatric intensive care unit. Crit Care Med. Galla J. J Am Soc Nephrol. Metabolic alkalosis in patients with renal failure.
Nephrol Dial Transplant. Kaklamanos M, Perros P. Milk alkali symdrome without the milk. Hypoventilation in a dialysis patient with severe metabolic alkalosis: Treatment by dialysis. Blood Purif. Conventional bicarbonate haemodialysis in postgastrectomy metabolic alkalosis. Singapore Med J. Metabolic alkalosis in a hemodialysis patient-successful treatment with a proton pump inhibitor.
Clin Nephrol. Acetazolamide in the treatment of metabolic alkalosis in critically ill patients. Heart lung. Schwenk MH, St. Acetazolamide toxicity and pharmacokinetics in patients receiving hemodialysis. Support Center Support Center. External link. The kidneys and lungs maintain the balance proper pH level of chemicals called acids and bases in the body.
Acidosis occurs when acid builds up or when bicarbonate a base is lost. Acidosis is classified as either respiratory or metabolic acidosis. Respiratory acidosis develops when there is too much carbon dioxide an acid in the body. This type of acidosis is usually caused when the body is unable to remove enough carbon dioxide through breathing.
Other names for respiratory acidosis are hypercapnic acidosis and carbon dioxide acidosis. Causes of respiratory acidosis include:.
Metabolic acidosis develops when too much acid is produced in the body. It can also occur when the kidneys cannot remove enough acid from the body. There are several types of metabolic acidosis:. Lactic acidosis is a buildup of lactic acid.
Lactic acid is mainly produced in muscle cells and red blood cells. It forms when the body breaks down carbohydrates to use for energy when oxygen levels are low. This can be caused by:. Metabolic acidosis symptoms depend on the underlying disease or condition. Metabolic acidosis itself causes rapid breathing.
Confusion or lethargy may also occur. Severe metabolic acidosis can lead to shock or death. Prevention depends on the cause of the acidosis. Respiratory acidosis occurs when the blood is overly acidic due to an excess of carbonic acid, resulting from too much CO 2 in the blood. Respiratory acidosis can result from anything that interferes with respiration, such as pneumonia, emphysema, or congestive heart failure.
Respiratory alkalosis occurs when the blood is overly alkaline due to a deficiency in carbonic acid and CO 2 levels in the blood. This condition usually occurs when too much CO 2 is exhaled from the lungs, as occurs in hyperventilation, which is breathing that is deeper or more frequent than normal. An elevated respiratory rate leading to hyperventilation can be due to extreme emotional upset or fear, fever, infections, hypoxia, or abnormally high levels of catecholamines, such as epinephrine and norepinephrine.
Surprisingly, aspirin overdose—salicylate toxicity—can result in respiratory alkalosis as the body tries to compensate for initial acidosis. Watch this video to see a demonstration of the effect altitude has on blood pH. What effect does high altitude have on blood pH, and why? Various compensatory mechanisms exist to maintain blood pH within a narrow range, including buffers, respiration, and renal mechanisms.
Although compensatory mechanisms usually work very well, when one of these mechanisms is not working properly like kidney failure or respiratory disease , they have their limits. If the pH and bicarbonate to carbonic acid ratio are changed too drastically, the body may not be able to compensate. Moreover, extreme changes in pH can denature proteins. Extensive damage to proteins in this way can result in disruption of normal metabolic processes, serious tissue damage, and ultimately death.
Respiratory compensation for metabolic acidosis increases the respiratory rate to drive off CO 2 and readjust the bicarbonate to carbonic acid ratio to the level. This adjustment can occur within minutes. Respiratory compensation for metabolic alkalosis is not as adept as its compensation for acidosis. The normal response of the respiratory system to elevated pH is to increase the amount of CO 2 in the blood by decreasing the respiratory rate to conserve CO 2. There is a limit to the decrease in respiration, however, that the body can tolerate.
Hence, the respiratory route is less efficient at compensating for metabolic alkalosis than for acidosis. Metabolic and renal compensation for respiratory diseases that can create acidosis revolves around the conservation of bicarbonate ions.
These processes increase the concentration of bicarbonate in the blood, reestablishing the proper relative concentrations of bicarbonate and carbonic acid.
Lab tests for pH, CO 2 partial pressure pCO 2 ,and HCO 3 — can identify acidosis and alkalosis, indicating whether the imbalance is respiratory or metabolic, and the extent to which compensatory mechanisms are working. The blood pH value, as shown in Table 2, indicates whether the blood is in acidosis, the normal range, or alkalosis. The pCO 2 and total HCO 3 — values aid in determining whether the condition is metabolic or respiratory, and whether the patient has been able to compensate for the problem.
Table 2 lists the conditions and laboratory results that can be used to classify these conditions. Metabolic acid-base imbalances typically result from kidney disease, and the respiratory system usually responds to compensate.
Metabolic acidosis is problematic, as lower-than-normal amounts of bicarbonate are present in the blood.
Respiratory acidosis is problematic, as excess CO 2 is present in the blood.
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