Breath ketones

Toxicity. Breathing moderate amounts of methyl ethyl ketone (MEK) for short periods of time can cause adverse effects on the nervous system ranging from headaches, dizziness, nausea, and numbness in the fingers and toes to unconsciousness. Its vapors are irritating to the skin, eyes, nose, and throat and can damage the eyes. Repeated exposure to moderate to high amounts may cause liver and kidney effects. 

Diabetic acidosis can develop in a matter of hours. Therefore, under certain circumstances, doctors may ask a diabetic patient to test for ketones at home using special test strips that can detect ketones in urine. For example, doctors recommend that diabetic patients test their urine every 4 to 6 hours if their blood sugar levels are very high. Patients should also test for ketones if they are sick with a cold or the flu, or if they experience any of the symptoms of acidosis. These symptoms include a very dry mouth, frequent urination, shortness of breath, and fruity smelling breath. Diabetic acidosis can be life-threatening, leading to a diabetic coma or death. It needs immediate medical care. Diabetic acidosis is also called ketoacidosis. 

Endrin and endrin aldehyde can enter your body when you eat foods or drink beverages or breathe air that contain this substance, or when it comes in contact with your skin. When endrin enters your body in any of these ways, it is rapidly changed into other substances. Endrin and its metabolic breakdown products are rapidly removed from the body, usually within a few days, through the urine and feces. There is some evidence that small amounts of endrin may remain in the fatty tissue of your body when you are exposed to high levels. No information is known about how endrin aldehyde or endrin ketone leaves the body. 

O Ketoacidosis is a dangerous condition that is characterized by the acidification of the blood and an acetone odour on the breath. The condition occurs when levels of oxaloacetic acid for the citric acid cycle are low. This leads to a buildup of acetyl CoA molecules, which the liver metabolizes to produce acidic ketone bodies. Since carbohydrates are the main source of oxaloacetic acid in the body, high-protein, low-carbohydrate diets have been linked to ketoacidosis. 

The increased degradation of fat that occurs in insulin deficiency also has serious effects. Some of the fatty acids that accumulate in large quantities are taken up by the liver and used for lipoprotein synthesis (hyperlipidemia), and the rest are broken down into acetyl CoA. As the tricarboxylic acid cycle is not capable of taking up such large quantities of acetyl CoA, the excess is used to form ketone bodies (acetoacetate and p-hydroxy-butyrate see p. 312). As H"" ions are released in this process, diabetics not receiving adequate treatment can suffer severe metabolic acidosis (diabetic coma). The acetone that is also formed gives these patients breath a characteristic odor. In addition, large amounts of ketone body anions appear in the urine (ketonuria). 

Acetone and several other ketones are produced naturally in the liver as a result of fat metabolism. Ketone blood levels are typically around 0.001%. The lack of carbohydrates in a person s diet results in greater fat metabolism, causing ketone levels in the blood to increase. This condition is called ketosis. People on low-carbohydrate diets and diabetics may have problems with ketosis because of a greater amount of fat in the diet. An indicator of ketosis is the smell of acetone on a persons breath. 

Acetone is volatile and is exhaled, and in uncontrolled diabetes, the breath has a characteristic odor sometimes mistaken for ethanol. A diabetic individual who is experiencing mental confusion due to high blood glucose is occasionally misdiagnosed as intoxicated, an error that can be fatal. The overproduction of ketone bodies, called ketosis, results in greatly increased concentrations of ketone bodies in the blood (ketonentia) and urine (lcetonuria). 

Many organocadmium compounds are known but few have been of commercial importance. Wanklyn first isolated diethyl cadmium in 1856. The properties of this and other dialkylcadmiums are listed in Table 4. In general, these materials are prepared by reaction of an anhydrous cadmium halide with a Grignard or alkyUithium reagent followed by distillation of the volatile material in an inert atmosphere or in vacuo. Only the liquid dimethyl compound is reasonably stable and then only when stored in a sealed tube. Dimethylcadmium is mildly pyrophoric in air and produces dense clouds of white, then brown, cadmium oxide smoke, which is highly toxic if breathed (45). When dropped into water, the liquid sinks in large droplets that decompose with a series of small explosive jerks and pops. For this reason, and particularly because of the low thermal stability, most dialkylcadmium materials are prepared and used in situ without separation, eg, in the conversion of acid chlorides to speciality ketones (qv) ... 

Synthesis of the ketone bodies HMG CoA is cleaved to produce acetoacetate and acetyl CoA, as shown in Figure 16.23, Acetoacetate can be reduced to form 3-hydroxybutyrate with NADH as the hydrogen donor. Acetoacetate can also spontaneously decarboxylate in the blood to form acetone—a volatile, biologically non-metabolized compound that can be released in the breath. [Note The equilibrium between acetoacetate and 3-hydroxybutyrate is determined by the NADVNADH ratio. Because this ratio is high during fatty acid oxidation, 3-hydroxy-butyrate synthesis is favored.]... 

Ition of the ketone bodies may be as high as 5000 mg/24 hr, and the blood concentration may reach 90 mg/dl (versus less than 3 mg/dL in normal individuals). A frequent symptom of diabetic ketoacidosis is a fruity odor on the breath which result from increased production of acetone. An elevation of the ketone body concentration in the blood results in acidemia. [Note The carboxyl group of a ketone body has a pKa about 4. Therefore, each ketone body loses a proton (H+) as it circulates in the blood, which lowers the pH of the body. Also, excretion of glucose and ketone bodies in the urine results in dehydration of the body. Therefore, the increased number of H+, circulating in a decreased volume of plasma, can cause severe acidosis (ketoacidosis)]. Ketoacidosis may also be seen in cases of fasting (see p. 327). 

Derivatization is a procedure in which analyte is chemically modified to make it easier to detect or separate. For example, formaldehyde and other aldehydes and ketones in air, breath, or cigarette smoke25 can be trapped and derivatized by passing air through a tiny cartridge containing 0.35 g of silica coated with 0.3 wt% 2,4-dinitrophenylhydrazine. Carbonyls are converted into the 2,4-dinitrophenylhydrazone derivative, which is eluted with 5 mL of acetonitrile and analyzed by HPLC. The products are readily detected by their strong ultraviolet absorbance near 360 nm. 

The signs and symptoms of diabetes consist of thirst, anorexia, nausea, vomiting, abdominal pain, headache, drowsiness, weakness, coma, severe acidosis, air hunger (Kussmaul s breathing), sweetish odor of the breath, hyperglycemia, decreased blood bicarbonate level, decreased blood pH, and plasma that is strongly positive for ketone bodies. 

The IUPAC rules for naming ketones append the suffix -one to the parent name. The position of the ketone carbon is indicated by a locant number. Figure 11.37 gives three nomenclature examples of ketones. The simplest ketone, propanone, is commonly known as acetone. Acetone is an excellent solvent for most organic compounds and is the main ingredient in fingernail polish remover. Acetone is one of the ketone bodies that build up in the bloodstream from excessive metabolism of fats. Because ketones typically have a sweet taste and odor, this can give a patient with ketosis a characteristic acetone breath. ... 

A number of organic compounds can be measured as the unmetabolized compound in blood, urine, and breath. In some cases, the sample can be injected along with its water content directly into a gas chromatograph. Direct injection is used for the measurement of acetone, -butanol, dhnethylformamide, cyclopropane, halothane, methoxyflurane, diethyl ether, isopropanol, methanol, methyl-n-butyl ketone, methyl chloride, methylethyl ketone, toluene, trichloroethane, and trichloroethylene. 

Two molecules of acetyl CoA initially condense to form acetoacetyl CoA in a reaction which is essentially the reverse of the thiolysis step in (3-oxidation. The acetoacetyl CoA reacts with another molecule of acetyl CoA to form 3-hydroxy-3-methylglutaryl CoA (HMG CoA) (Fig. 5). This molecule is then cleaved to form acetoacetate and acetyl CoA. (HMG CoA is also the starting point for cholesterol biosynthesis see Topic K5.) The acetoacetate is then either reduced to D-3-hydroxybutyrate in the mitochondrial matrix or undergoes a slow, spontaneous decarboxylation to acetone (Fig. 5). In diabetes, acetoacetate is produced faster than it can be metabolized. Hence untreated diabetics have high levels of ketone bodies in their blood, and the smell of acetone can often be detected on their breath. 

Although acetone is a very minor product of normal metabolism, diabetics whose disease is not well-managed often have high levels of ketone bodies in their circulation. The acetone that is formed from decarboxylation of acetoacetate is excreted through the lungs, causing characteristic acetone breath. ... 

One symptom of untreated diabetes is the characteristic fruity smell of acetone in the patient s breath. Because diabetics cannot use carbohydrates properly, the body goes into a state called ketosis, in which it produces acetone and other ketones. 

Ketone bodies, produced mainly in the mitochondria of liver cells from acetyl-CoA, provide much of the energy to heart tissue, and during starvation to the brain. They inclnde acetone, acetoacetate and /3-hydroxybutyrate (Figure 1.11). The levels of acetone are mnch lower than those of the other two ketone bodies it cannot be converted back to acetyl-CoA and so is excreted in the urine or breathed out. 

Don t despise them, they re good fuels for your museles, brain and heart When your body s overloaded though, that s when your troubles start Ketone bodies. Ketone bodies, make acetone, lose COj You ean breathe those out, but wateh out—aeidosis does for you ... 

Her eyes fluttered open. .. David... It came out as a whisper, and I felt ny relief turn to be when I cau the sweet chembal odour of her breath. Ketoacidosis. Her body had started to break down its own fets, producing toxb levels of ketones m her bbod. She needed insulin, last. 

Alcohol-induced ketoacidosis must be differentiated from a similar metabolic complication in diabetes melli-tUS (E.S. Dillon et al., 1940 D.W. Jenkins et al., 1971). With chronic alcohol consumption and concurrent malnutrition, metabolic acidosis is caused by a still unclear multifaceted pathogenesis (hypoinsulinaemia, lipolysis, extreme increase in free fatty acids, rise in ketone bodies). The clinical picture shows nausea, vomiting, dehydration, hyperventilation, fruity odour on breath, aceton-uria and acetonaemia as well as a moderate form of hyperglycaemia. This syndrome probably occurs more often than has been hitherto assumed. (54)... 

The molecular structures of the ketone bodies acetoacetate, p-hydnoxybutyrate, and acetone are shovvn in Figure 4,64. Acetone is formed by nonerKymatic breakdown of acetoacetate. Between 20 and 75% of the acetone formed can be metabo lized to usable energy by humans. Experiments with rats determined that acetone is metabolized via acetyl-CoA (Kosug cf fl/ 1 56). Unmetaboiiaed acetone is excreted in the urine or released in the breath. The odor of acetone on a person s breath reveals that the person either has uncontrolled diabetes or is fasting. The acetoacetate and 3-liydroxybutyrate formed in the body can be an important source of energy acetone is relatively unimportant. 

The glucagon/insulin ratio can rise under certain pathological conditions (i.e., insulin-dependent diabetes). A small percentage of diabetics develop ketoacidosis, a condition that results from the overproduction and underuhlization of ketone bodies. Increased concentrations of p hydmxybutyrate and acetoacetate, which are acids, can cause a drop in the pH of the blood. This acidification, known as acidosis, can impair the ablLity of the heart to contract and result in a loss of consciousness and coma, which, in rare cases, may be fatal. Diabetic ketoacidosis may manifest as abdominal pain, nausea, and vomiting. A subject may hyperventilate (breathe quickly and deeply) to correct acidosis, as described under Sodium, Potassium, and Water in Chapter 10. It is the responsibility of the clinician, when confronted with a subject whose breath smells of acetone or who is hyperventilating, to facilitate prompt treatment. 

A 20-year-old woman with diabetes melli-tus was admitted to the hospital in a semiconscious state with fever, nausea, and vomiting. Her breath smelled of acetone. A urine sample was strongly positive for ketone bodies. Which of the following statements about this woman is TRUE ... 

---