Electrolyte/acid-base disturbance

Dehydration, electrolyte imbalances, and acid-base disturbances may be evident in complex and prolonged nausea and vomiting. 

Arterial blood gases, serum electrolytes, physical examination findings, the medical history, and the patient s recent medications must be reviewed in order to establish the etiology of a given acid-base disturbance. 

Acid-base disturbances are common clinical problems that are not difficult to analyze if approached in a consistent manner. The pH, PaC02, and HCO, should be inspected to identify all abnormal values. This should lead to an assessment of which deviations represent the primary abnormality and which represent compensatory changes. The serum electrolytes should always be used to calculate the anion gap. In cases in which the anion gap is increased, the excess anion gap should be added back to the measured HC03 . The anion gap and the excess... 

Continuous cardiovascular and hemodynamic monitoring should be used for significant pH disturbances, as the most serious sequelae of acid-base disorders include electrolyte abnormalities, cardiac dysrhythmias, and systemic hypotension. 

PN therapy is associated with significant complications, both with short- and long-term therapy. Many complications are related to overfeeding (Table 97—7). Metabolic complications include hyperglycemia, hypoglycemia, hyperlipidemia, hypercapnia, electrolyte disturbances, refeeding syndrome, and acid-base... 

Lee E. Morrow, MD, MS Assistant Professor of Medicine Creighton University Medical Center Omaha, Nebraska Chapter 24 Fluids and Electrolytes Chapter 25 Acid-Base Disturbances... 

Underlying precipitating factors should be corrected by ensuring proper oxygenation and ventilation and by correcting acid-base or electrolyte disturbances. 

The therapeutic goals of diarrhea treatment are to manage the diet prevent excessive water, electrolyte, and acid-base disturbances provide symptomatic relief treat curable causes of diarrhea and manage secondary... 

Although acid-base and electrolyte disturbances were not reported in the clinical trials, these disturbances have been reported with oral CA inhibitors and have, in some instances, resulted in drug interactions (eg, toxicity associated with high-dose salicylate therapy). 

The most effective treatment is haemodialysis, which allows the removal of salicylate and the correction of acid-base, fluid, and electrolyte disturbances, and is the preferred treatment for severe or complicated salicylate poisoning. 

Disturbances in the GI system, such as nausea and cramps, may occur with laxative use. With prolonged use, serious lower GI irritation, including spastic colitis, may occur. Fluid and electrolyte abnormalities are also a potential problem. Excessive loss of water and the concomitant loss of electrolytes may transpire, resulting in dehydration and possible acid-base imbalances.44 These abnormalities are especially significant in older or debilitated patients. Finally, chronic administration may result in a laxative dependence when bowel evacuation has become so subservient to laxative use that the normal mechanisms governing evacuation and defecation are impaired. 

At diagnosis, new patients with type 1 diabetes may exhibit ketoacidosis with resultant acid-base and electrolyte disturbances. The most common abnormality is hyponatremia, which is often due to the movement of water to the extravascular space. Volume contraction may lead to elevations in blood urea nitrogen (BUN) and creatinine, as well as mild erythrocytosis. Leukocytosis may also exist in the absence of infection, and serum triglycerides and urine glucose are almost universally elevated. 

Solutions correcting water, electrolyte and acid-base disturbances... 

O Regan S, Carson S, Chesney RW, Drummond KN. Electrolyte and acid-base disturbances in the management of leukemia. Blood 1977 49(3) 345-53. 

Hemodialysis is recommended for acutely poisoned patients with salicylate levels greater than 80-lOOmg/ dL, acidosis, CNS dysfunction, or pulmonary edema. Chronic intoxication with levels >60 mg/ dL is a further indication. While hemoperfusion is also effective, hemodialysis is preferred to correct acid-base and electrolyte disturbances. 

The volume to be infused and rate of delivery are only part of the therapeutic plan for fluid therapy, albeit the most important in acute resuscitation. The electrolyte and acid-base status of the horse should also be considered and fluids chosen to help to correct physiological imbalances. Unfortunately, it is not possible to predict electrolyte and acid-base disturbances accurately based on clinical signs. Seemingly similar clinical presentations may have a quite different pathophysiology (Brownlow Hutchins 1982, Svendsen et al 1979). The recent availability of relatively inexpensive, portable blood gas and electrolyte measuring equipment (Grosenbaugh et al 1998) has made determining the acid-base status possible in ambulatory equine practice and allows the field veterinarian to monitor and treat these disturbances. As stated earlier, in the absence of specific laboratory information, fluid therapy should probably be limited to isotonic polyionic crystalloid fluids, possibly with the addition of 10-20 mEq/1 potassium chloride in the maintenance phase. 

Johnson P J 1995 Electrolyte and acid-base disturbances in the horse. Veterinary Clinics of North America Equine Practice 11 491-514... 

There is no specific antidote. Supportive care should be instituted for all patients with history of serious boric acid exposure. Substantial recent ingestions may benefit from administration of activated charcoal. Fluid and electrolyte balance, correction of acid/base disturbance, and control of seizures are essential to therapy. Hemodialysis has been successfully used to treat acute boric acid poisoning. Sodium bicarbonate may be used for any metabolic acidosis. 

Determination of plasma and urine osmolality can be useful in the assessment of electrolyte and acid-base disorders. Comparison of plasma and urine osmolalities can determine the appropriateness and status of water regulation by the kidneys in settings of severe electrolyte disturbances, as might occur in diabetes insipidus or the syndrome of inappropriate antidiuretic hormone (SIADH) (see Chapters 45 and 50). The major osmotic substances in normal plasma are Ha, Cr, glucose, and urea thus expected plasma osmolality can be calculated from the following empirical equation ... 

Many pathological conditions are accompanied by disturbances of the acid-base balance and electrolyte composition of the blood. These changes are usually reflected in the acid-base pattern and anion-cation composition of ECF, as measured in blood. However, results obtained on blood or plasma may not always reflect the acid-base status of the ICF. 

Abnormalities of acid-base status of the blood are always accompanied by characteristic changes in electrolyte concentrations in the plasma, especially in metabolic acid-base disorders. Hydrogen ions cannot accumulate without concomitant accumulation of anions, such as CL or lactate, or without exchange for cations, such as or NaL Consequently, electrolyte composition of blood serum or plasma is often determined along with measurements of blood gases and pH and to assess acid-base disturbances. 

Most acute diarrhea is self-limiting, subsiding within 72 hours. However, infants, young children, the elderly, and debilitated persons are at risk for morbid and mortal events in prolonged or voluminous diarrhea. These groups are at risk for water, electrolyte, and acid-base disturbances, and potentially cardiovascular collapse and death. The prognosis for chronic diarrhea depends on the cause for example, diarrhea secondary to diabetes mellitus waxes and wanes throughout life. 

Arterial blood gases and serum electrolytes should be measured regularly in patients with CKD. These patients should also have a complete medical history and review of medications to determine if there are other potential causes of acid-base disturbances (e.g., diabetic ketoacidosis, ingestion of toxins, or GI disorders). The anion gap, indicating the differences in unmeasured anions and cations, should also be calculated (see Chap. 51). An elevated anion gap (>17 mEq/L) is often present in those with CKD due to the accumulation of organic anions, phosphates, and sulfates. 

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