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A pH under 7.1 is an emergency, due to the risk of cardiac arrhythmias, and may warrant treatment with intravenous bicarbonate. Bicarbonate is given at 50-100 mmol at a time under scrupulous monitoring of the arterial blood gas readings. This intervention, however, has some serious complications in lactic acidosis, and in those cases, should be used with great care.
If the acidosis is particularly severe and/or intoxication may be present, consultation with the nephrology team is considered useful, as dialysis may clear both the intoxication and the acidosis.
Several medical treatments shift potassium ions from the bloodstream into the cellular compartment, thereby reducing the risk of complications. The effect of these measures tends to be short-lived, but may temporize the problem until potassium can be removed from the body.
- Insulin (e.g. intravenous injection of 10-15 units of regular insulin along with 50 ml of 50% dextrose to prevent the blood sugar from dropping too low) leads to a shift of potassium ions into cells, secondary to increased activity of the sodium-potassium ATPase. Its effects last a few hours, so it sometimes must be repeated while other measures are taken to suppress potassium levels more permanently. The insulin is usually given with an appropriate amount of glucose to prevent hypoglycemia following the insulin administration.
- Salbutamol (albuterol), a β-selective catecholamine, is administered by nebulizer (e.g. 10–20 mg). This medication also lowers blood levels of K by promoting its movement into cells.
- Sodium bicarbonate may be used with the above measures if it is believed the person has metabolic acidosis.
Severe cases require hemodialysis or hemofiltration, which are the most rapid methods of removing potassium from the body. These are typically used if the underlying cause cannot be corrected swiftly while temporizing measures are instituted or there is no response to these measures.
Potassium can bind to agents in the gastrointestinal tract. Sodium polystyrene sulfonate with sorbitol (Kayexalate) has been approved for this use and can be given by mouth or rectally. However, careful clinical trials to demonstrate the effectiveness of sodium polystyrene are lacking, and use of sodium polystyrene sulfonate, particularly if with high sorbitol content, is uncommonly but convincingly associated with colonic necrosis. There are no systematic studies (>6 months) looking at the long-term safety of this medication. Another medication by the name of patiromer was approved in 2015.
Loop diuretics (furosemide, bumetanide, torasemide) and thiazide diuretics (e.g., chlorthalidone, hydrochlorothiazide, or chlorothiazide) can increase kidney potassium excretion in people with intact kidney function.
Fludrocortisone, a synthetic mineralocorticoid, can also increase potassium excretion by the kidney in patients with functioning kidneys. Trials of fludrocortisone in patients on dialysis have shown it to be ineffective.
Patiromer is a selective sorbent that is taken by mouth and works by binding free potassium ions in the gastrointestinal tract and releasing calcium ions for exchange, thus lowering the amount of potassium available for absorption into the bloodstream and increasing the amount that is excreted via the feces. The net effect is a reduction of potassium levels in the blood serum.
Direct removal of lactate from the body (e.g. with hemofiltration) is difficult, with limited evidence for benefit. In type A lactic acidosis, treatment consists of effective management of the underlying cause, and limited evidence supports the use of sodium bicarbonate solutions to improve the pH (which is associated with increased carbon dioxide generation and may reduce the calcium levels).
In type B lactic acidosis produced by medication, withdrawal of the medication may be necessary to resolve the lactic acidosis.
Lactic acidosis in the context of mitochondrial disorders (type B3) may be treated with a ketogenic diet and possibly with dichloroacetate (DCA), although this may be complicated by peripheral neuropathy and has a weak evidence base.
Treatment consists of oral bicarbonate supplementation. However, this will increase urinary bicarbonate wasting and may well promote a bicarbonate . The amount of bicarbonate given may have to be very large to stay ahead of the urinary losses. Correction with oral bicarbonate may exacerbate urinary potassium losses and precipitate hypokalemia. As with dRTA, reversal of the chronic acidosis should reverse bone demineralization.
Thiazide diuretics can also be used as treatment by making use of contraction alkalosis caused by them.
Intake of carbohydrates which must be converted to G6P to be utilized (e.g., galactose and fructose) should be minimized. Although elemental formulas are available for infants, many foods contain fructose or galactose in the forms of sucrose or lactose. Adherence becomes a contentious treatment issue after infancy.
The underlying cause determines the prognosis of lactic acidosis. In sepsis, elevated lactate levels correlate with mortality. The mortality of lactic acidosis in people taking metformin was previously reported to be 50%, but in more recent reports this was closer to 25%.
Persistent elevation of uric acid above 6.5 mg/dl warrants treatment with allopurinol to prevent uric acid deposition in kidneys and joints.
Because of the potential for impaired platelet function, coagulation ability should be checked and the metabolic state normalized before surgery. Bleeding time may be normalized with 1–2 days of glucose loading, and improved with ddavp. During surgery, iv fluids should contain 10% dextrose and no lactate.
A patient with GSD, type 1b was treated with a liver transplant at UCSF Medical Center in 1993 that resulted in the resolution of hypoglycemic episodes and the need for the patient to stay away from natural sources of sugar. Other patients have undergone this procedure as well with positive results. Although a liver transplant resulted in the resolution of hypoglycemia it did not however resolve the chronic neutropenia and the risk of infection among patients.
This is relatively straightforward. It involves correction of the acidemia with oral sodium bicarbonate, sodium citrate or potassium citrate. This will correct the acidemia and reverse bone demineralisation. Hypokalemia and urinary stone formation and nephrocalcinosis can be treated with potassium citrate tablets which not only replace potassium but also inhibit calcium excretion and thus do not exacerbate stone disease as sodium bicarbonate or citrate may do.
Serum pH is neither safely or easily altered. Therapies that alter pH principally alter the pH of urine, to discourage a possible complication of uricosuric therapy: formation of uric acid kidney stones due to increased uric acid in the urine (see Nephrolithiasis). Dietary supplements that can be used to make the urine more alkaline include sodium bicarbonate, potassium citrate, magnesium citrate, and Shohl's Solution (now replaced by Bicitra). Medications that have a similar effect include acetazolamide.
Following Le Chatelier's principle, lowering the blood concentration of uric acid may permit any existing crystals of uric acid to be gradually dissolved into the blood, whence the dissolved uric acid can be excreted. Maintaining a lower blood concentration of uric acid similarly should reduce the formation of new crystals. If the person has chronic gout or known tophi, then large quantities of uric acid crystals may have accumulated in joints and other tissues, and aggressive and/or long duration use of medications may be needed.
Medications most often used to treat hyperuricemia are of two kinds: xanthine oxidase inhibitors and uricosurics. Xanthine oxidase inhibitors decrease the production of uric acid, by interfering with xanthine oxidase. Uricosurics increase the excretion of uric acid, by reducing the reabsorption of uric acid once the kidneys have filtered it out of the blood. Some of these medications are used as indicated, others are used off-label. Several other kinds of medications have potential for use in treating hyperuricemia. In people receiving hemodialysis, sevelamer can significantly reduce serum uric acid, apparently by adsorbing urate in the gut. In women, use of combined oral contraceptive pills is significantly associated with lower serum uric acid.
Non-medication treatments for hyperuricemia include a low purine diet (see Gout) and a variety of dietary supplements. Treatment with lithium salts has been used as lithium improves uric acid solubility.
The goal for treatment of GSD type 0 is to avoid hypoglycemia. This is accomplished by avoiding fasting by eating every 3-4 hours during the day. At night, uncooked corn starch can be given because it is a complex glucose polymer. This will be acted on slowly by pancreatic amylase and glucose will be absorbed over a 6 hour period.
In the fetus, the normal range differs based on which umbilical vessel is sampled (umbilical vein pH is normally 7.25 to 7.45; umbilical artery pH is normally 7.20 to 7.38). In the fetus, the lungs are not used for ventilation. Instead, the placenta performs ventilatory functions (gas exchange). Fetal respiratory acidemia is defined as an umbilical vessel pH of less than 7.20 and an umbilical artery PCO of 66 or higher or umbilical vein PCO of 50 or higher.
Causes of increased anion gap include:
- Lactic acidosis
- Ketoacidosis
- Chronic renal failure (accumulation of sulfates, phosphates, urea)
- Intoxication:
- Organic acids, salicylates, ethanol, methanol, formaldehyde, ethylene glycol, paraldehyde, isoniazid
- Sulfates, metformin
- Massive rhabdomyolysis
A mnemonic can also be used - MUDPILES
- M-Methanol
- U-Uremia (chronic kidney failure)
- D-Diabetic ketoacidosis
- P-Paraldehyde
- I-Infection, Iron, Isoniazid, Inborn errors of metabolism
- L-Lactic acidosis
- E-Ethylene glycol (Note: Ethanol is sometimes included in this mnemonic, as well, although the acidosis caused by ethanol is actually primarily due to the increased production of lactic acid found in such intoxication.)
- S-Salicylates
A diet with carefully controlled levels of the amino acids leucine, isoleucine, and valine must be maintained at all times in order to prevent neurological damage. Since these three amino acids occur in all natural protein, and most natural foods contain some protein, any food intake must be closely monitored, and day-to-day protein intake calculated on a cumulative basis, to ensure individual tolerance levels are not exceeded at any time. As the MSUD diet is so protein-restricted, and adequate protein is a requirement for all humans, tailored metabolic formula containing all the other essential amino acids, as well as any vitamins, minerals, omega-3 fatty acids and trace elements (which may be lacking due to the limited range of permissible foods), are an essential aspect of MSUD management. These complement the MSUD patient's natural food intake to meet normal nutritional requirements without causing harm. If adequate calories cannot be obtained from natural food without exceeding protein tolerance, specialised low protein products such as starch-based baking mixtures, imitation rice and pasta may be prescribed, often alongside a protein-free carbohydrate powder added to food and/or drink, and increased at times of metabolic stress. Some patients with MSUD may also improve with administration of high doses of thiamine, a cofactor of the enzyme that causes the condition.
There is no proven treatment for congenital lactic acidosis. Treatments that are occasionally used or that are under investigation include the ketogenic diet and dichloroacetate. Other treatments aim to relieve symptoms – for example, anticonvulsants may be used to relieve seizures.
Treatment of uncompensated metabolic acidosis is focused upon correcting the underlying problem. When metabolic acidosis is severe and can no longer be compensated for adequately by the lungs, neutralizing the acidosis with infusions of bicarbonate may be required.
The administration of sodium bicarbonate solution to rapidly improve the acid levels in the blood is controversial. There is little evidence that it improves outcomes beyond standard therapy, and indeed some evidence that while it may improve the acidity of the blood, it may actually worsen acidity inside the body's cells and increase the risk of certain complications. Its use is therefore discouraged, although some guidelines recommend it for extreme acidosis (pH<6.9), and smaller amounts for severe acidosis (pH 6.9–7.0).
Usually MSUD patients are monitored by a dietitian. Liver transplantation is another treatment option that can completely and permanently normalise metabolic function, enabling discontinuation of nutritional supplements and strict monitoring of biochemistry and caloric intake, relaxation of MSUD-related lifestyle precautions, and an unrestricted diet. This procedure is most successful when performed at a young age, and weaning from immunosuppressants may even be possible in the long run. However, the surgery is a major undertaking requiring extensive hospitalisation and rigorous adherence to a tapering regime of medications. Following transplant, the risk of periodic rejection will always exist, as will the need for some degree of lifelong monitoring in this respect. Despite normalising clinical presentation, liver transplantation is not considered a cure for MSUD. The patient will still carry two copies of the mutated BKAD gene in each of their own cells, which will consequently still be unable to produce the missing enzyme. They will also still pass one mutated copy of the gene on to each of their biological children. As a major surgery the transplant procedure itself also carries standard risks, although the odds of its success are greatly elevated when the only indication for it is an inborn error of metabolism. In absence of a liver transplant, the MSUD diet must be adhered to strictly and permanently. However, in both treatment scenarios, with proper management, those afflicted are able to live healthy, normal lives without suffering the severe neurological damage associated with the disease.
It is important for MADD patients to maintain strength and fitness without exercising or working to exhaustion. Learning this balance may be more difficult than normally, as muscle pain and fatigue may be perceived differently from normal individuals.
Symptomatic relief from the effects of MADD may sometimes be achieved by administering ribose orally at a dose of approximately 10 grams per 100 pounds (0.2 g/kg) of body weight per day, and exercise modulation as appropriate. Taken hourly, ribose provides a direct but limited source of energy for the cells. Patients with myoadenylate deaminase deficiency do not retain ribose during heavy exercise, so supplementation may be required to rebuild levels of ATP.
Creatine monohydrate could also be helpful for AMPD patients, as it provides an alternative source of energy for anaerobic muscle tissue and was found to be helpful in the treatment of other, unrelated muscular myopathies.
The main aims in the treatment of diabetic ketoacidosis are replacing the lost fluids and electrolytes while suppressing the high blood sugars and ketone production with insulin. Admission to an intensive care unit or similar high-dependency area or ward for close observation may be necessary.
Causes include:
The newest mnemonic was proposed in "The Lancet" reflecting current causes of anion gap metabolic acidosis:
- G — glycols (ethylene glycol & propylene glycol)
- O — oxoproline, a metabolite of paracetamol
- L — L-lactate, the chemical responsible for lactic acidosis
- D — D-lactate
- M — methanol
- A — aspirin
- R — renal failure
- K — ketoacidosis, ketones generated from starvation, alcohol, and diabetic ketoacidosis
The mnemonic MUDPILES is commonly used to remember the causes of increased anion gap metabolic acidosis.
- M — Methanol
- U — Uremia (chronic kidney failure)
- D — Diabetic ketoacidosis
- P — Paracetamol, Propylene glycol (used as an inactive stabilizer in many medications; historically, the "P" also stood for Paraldehyde, though this substance is not commonly used today)
- I — Infection, Iron, Isoniazid (which can cause lactic acidosis in overdose), Inborn errors of metabolism (an especially important consideration in pediatric patients)
- L — Lactic acidosis
- E — Ethylene glycol (Note: Ethanol is sometimes included in this mnemonic as well, although the acidosis caused by ethanol is actually primarily due to the increased production of lactic acid found in such intoxication.)
- S — Salicylates
Another frequently used mnemonic is KARMEL.
- K — Ketoacidosis
- A — aspirin
- R — Renal failure
- M — Methanol
- E — Ethylene glycol
- L — Lactic acidosis
Another frequently used mnemonic is KULT.
- K — Ketoacidosis (DKA, AKA)
- U — Uremia
- L — Lactic acidosis
- T — Toxins (Ethylene glycol, methanol, as well as drugs, such as aspirin, Metformin)
The preferred mnemonic of D. Robert Dufour, the chief of the Pathology and Laboratory Medicine Service, Veterans Affairs Medical Center, is DUMPSALE, which omits the I of MUDPILES as the proposed values of *I* are exceedingly rare in clinical practice.
- D — Diabetic ketoacidosis
- U — Uremia
- M — Methanol
- P — Paraldehyde
- S — Salicylates
- A — Alcoholic ketoacidosis
- L — Lactic acidosis
- E — Ethylene Glycol
The mnemonic for the [rare, in comparison] toxins is ACE GIFTs: Aspirin, Cyanide, Ethanolic ketosis, Glycols [ ethylene and propylene ], Isoniazid, Ferrous iron, Toluene. Most of these cause a lactic acidosis.
Direct treatment that stimulates the pyruvate dehydrogenase complex (PDC), provides alternative fuels, and prevents acute worsening of the syndrome. However, some correction of acidosis does not reverse all the symptoms. CNS damage is common and limits a full recovery. Ketogenic diets, with high fat and low carbohydrate intake have been used to control or minimize lactic acidosis and anecdotal evidence shows successful control of the disease, slowing progress and often showing rapid improvement. No study has yet been published demonstrating the effectiveness of the ketogenic diet for treatment of PDCD.
There is some evidence that dichloroacetate reduces the inhibitory phosphorylation of pyruvate dehydrogenase complex and thereby activates any residual functioning complex. Resolution of lactic acidosis is observed in patients with E1 alpha enzyme subunit mutations that reduce enzyme stability. However, treatment with dichloroacetate does not improve neurological damage. Oral citrate is often used to treat acidosis.
When acidosis is present on blood tests, the first step in determining the cause is determining the anion gap. If the anion gap is high (>12 mEq/L), there are several potential causes.
High anion gap metabolic acidosis is a form of metabolic acidosis characterized by a high anion gap (a medical value based on the concentrations of ions in a patient's serum). An anion gap is usually considered to be high if it is over 12 mEq/L.
High anion gap metabolic acidosis is caused generally by acid produced by the body. More rarely, high anion gap metabolic acidosis may be caused by ingesting methanol or overdosing on aspirin. The Delta Ratio is a formula that can be used to assess elevated anion gap metabolic acidosis and to evaluate whether mixed acid base disorder (metabolic acidosis) is present.
The list of agents that cause high anion gap metabolic acidosis is similar to but broader than the list of agents that cause a serum osmolal gap.
In general, the cause of a hyperchloremic metabolic acidosis is a "loss of base", either a gastrointestinal loss or a renal loss.
- Gastrointestinal loss of bicarbonate ()
- Severe diarrhea (vomiting will tend to cause hypochloraemic alkalosis)
- Pancreatic fistula with loss of bicarbonate rich pancreatic fluid
- Nasojejunal tube losses in the context of small bowel obstruction and loss of alkaline proximal small bowel secretions
- Chronic laxative abuse
- Renal causes
- Proximal renal tubular acidosis with failure of resorption
- Distal renal tubular acidosis with failure of secretion
- Long-term use of a carbonic anhydrase inhibitor such as acetazolamide
- Other causes
- Ingestion of ammonium chloride, hydrochloric acid, or other acidifying salts
- The treatment and recovery phases of diabetic ketoacidosis
- Volume resuscitation with 0.9% normal saline provides a chloride load, so that infusing more than 3-4L can cause acidosis
- Hyperalimentation ("i.e.", total parenteral nutrition)