Acid-base imbalances acidosis

In early cardiac arrest, adequate alveolar ventilation is the primary means of limiting carbon dioxide accumulation and controlling the acid base imbalance. With arrests of long duration, buffer therapy is often necessary. Sodium bicarbonate administration for cardiac arrest is controversial because there are few clinical data supporting its use, and it may have some detrimental effects. Sodium bicarbonate can be used in special circumstances (i.e., underlying metabolic acidosis, hyperkalemia, salicylate overdose, or tricychc antidepressant overdose). The dosage should be guided by laboratory analysis if possible. 

It is important to reverse the acid-base imbalance of lactate acidosis by the i.v. infusion of bicarbonate. 

Acidosis seen during cardiac arrest results from decreased blood flow and inadequate ventilation. Chest compressions generate approximately 20% to 30% of normal cardiac output, leading to inadequate organ perfusion, tissue hypoxia, and metabohc acidosis. In addition, the lack of ventilation causes retention of carbon dioxide, leading to respiratory acidosis. This combined acidosis produces not only reduced myocardial contractility and negative inotropic effect but also the appearance of arrhythmias because of a lower fibrillation threshold. In early cardiac arrest, adequate alveolar ventilation is the mainstay of control to limit the accumulation of carbon dioxide and control the acid-base imbalance. With arrests of long duration, buffer therapy often is necessary. 

Two adjectives describe the general cause or origin of pH imbalances in body fluids metabolic and respiratory. Respiratory acid-base imbalances (respiratory acidosis and respiratory alkalosis) result from abnormal breathing patterns. Metabolic acidosis and metabohc alkalosis are caused by factors other than abnormal breathing. 

As stated in the introductory chapters, acid-base balance is focused on regulating the hydrogen ion concentration. When body fluids have an excessive hydrogen ion concentration, the patient is deemed to be in a state of acidosis. When the hydrogen ion concentration is low, the patient is in a state of alkalosis. Compensation of an acid-base imbalance can occur when the body has partially adjusted, returning the acid-base balance to normal, even though bicarbonate and carbon dioxide levels remain abnormal. The underlying problem must be corrected to fully reverse the imbalance. 

Treatment for the respiratory damage involves oxygen supplements, intubation, and artificial ventilation when indicated, as well as the use of a hyperbaric chamber to remove carbon monoxide, if needed. Any restriction to the chest owing to burned skin is removed surgically. The nurse must monitor arterial blood gases and oxygen saturation levels to determine the effectiveness of treatment. In addition, the nurse should monitor for signs of acidosis and related acid-base imbalances. <3 ... 

In all cases of acid-base imbalance, three basic rules should be followed (1) rely on a medical doctor for diagnosis and prescribed treatment, (2) treat the primary cause of the acidosis or alkalosis, and (3) make every effort to aid the various compensatory responses of the lungs and kidneys. 

This electrolyte plays a vital role in the acid-base balance of the body. Bicarbonate may be given IV as sodium bicarbonate (NaHC03) in the treatment of metabolic acidosis, a state of imbalance that may be seen in diseases or situations such as severe shock, diabetic acidosis, severe diarrhea, extracorporeal circulation of blood, severe renal disease, and cardiac arrest. Oral sodium bicarbonate is used as a gastric and urinary alkalinizer. It may be used as a single drug or may be found as one of the ingredients in some antacid preparations. It is also useful in treating severe diarrhea accompanied by bicarbonate loss. 

The pH indicates an excess presence of hydrogen ions termed acidosis (pH < 7.35) or low levels of hydrogen ions termed alkalosis (pH > 7.45). The pH only determines the overall state of acid-base balance but does not indicate the source of the imbalance uidess viewed in combination with other test values (Pco and HCO ). 4... 

If the acidosis causing the hyperkalemia is extreme, bicarbonate may be administered to restore acid-base balance. If other electrolyte imbalances are noted, the appropriate treatment (e.g., chloride replacement) should be implemented. Care should be taken when providing supplements for electrolyte replacement. Electrolyte and acid-base levels should be monitored carefully to prevent overtreatment and additional electrolyte imbalance or alkalosis. 

Sensory organ function diminishes, most notably the sense of taste, which migh affect dietary intake leading to malnutrition and decreased protein intake with related fluid balance issues, as well as electrolyte imbalance, in addition to anemia that could affect oxygenation and acid-base balance (lactic acidosis). 

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