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Hypokalemia
Hypokalemia is a low level of potassium (K+) in the blood serum. Mild low potassium does not typically cause symptoms. Symptoms may include feeling tired, leg cramps, weakness, and constipation. Low potassium also increases the risk of an abnormal heart rhythm, which is often too slow and can cause cardiac arrest. Causes of hypokalemia include vomiting, diarrhea, medications like furosemide and steroids, dialysis, diabetes insipidus, hyperaldosteronism, hypomagnesemia, and not enough intake in the diet. Normal potassium levels in humans are between 3.5 and 5.0 mmol/L (3.5 and 5.0 mEq/L) with levels below 3.5 mmol/L defined as hypokalemia. It is classified as severe when levels are less than 2.5 mmol/L. Low levels may also be suspected based on an electrocardiogram (ECG). The opposite state is called hyperkalemia that means high level of potassium in the blood serum. The speed at which potassium should be replaced depends on whether or not there are symptom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Furosemide
Furosemide, sold under the brand name Lasix among others, is a loop diuretic medication used to treat edema due to heart failure, liver scarring, or kidney disease. Furosemide may also be used for the treatment of high blood pressure. It can be taken intravenously or orally. When given intravenously, furosemide typically takes effect within five minutes; when taken orally, it typically metabolizes within an hour. Common side effects include orthostatic hypotension (decrease in blood pressure while standing, and associated lightheadedness), tinnitus (ringing in the ears), and photosensitivity (sensitivity to light). Potentially serious side effects include electrolyte abnormalities, low blood pressure, and hearing loss. It is recommended that serum electrolytes (especially potassium), serum , creatinine, BUN levels, and liver and kidney functioning be monitored in patients taking furosemide. It is also recommended to be alert for the occurrence of any potential blood d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypomagnesemia
Magnesium deficiency is an electrolyte disturbance in which there is a low level of magnesium in the body. Symptoms include tremor, poor coordination, muscle spasms, loss of appetite, personality changes, and nystagmus. Complications may include seizures or cardiac arrest such as from torsade de pointes. Those with low magnesium often have low potassium. Causes include low dietary intake, alcoholism, diarrhea, increased urinary loss, and poor absorption from the intestines. Some medications may also cause low magnesium, including proton pump inhibitors (PPIs) and furosemide. The diagnosis is typically based on finding low blood magnesium levels, also called hypomagnesemia. Normal magnesium levels are between 0.6 and 1.1 mmol/L (1.46–2.68 mg/dL) with levels less than 0.6 mmol/L (1.46 mg/dL) defining hypomagnesemia. Specific electrocardiogram (ECG) changes may be seen. Treatment is with magnesium either by mouth or intravenously. For those with sev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electrocardiography
Electrocardiography is the process of producing an electrocardiogram (ECG or EKG), a recording of the heart's electrical activity through repeated cardiac cycles. It is an electrogram of the heart which is a graph of voltage versus time of the electrical activity of the heart using electrodes placed on the skin. These electrodes detect the small electrical changes that are a consequence of cardiac muscle depolarization followed by repolarization during each cardiac cycle (heartbeat). Changes in the normal ECG pattern occur in numerous cardiac abnormalities, including: * Cardiac rhythmicity, Cardiac rhythm disturbances, such as atrial fibrillation and ventricular tachycardia; * Inadequate coronary artery blood flow, such as myocardial ischemia and myocardial infarction; * and electrolyte disturbances, such as hypokalemia. Traditionally, "ECG" usually means a 12-lead ECG taken while lying down as discussed below. However, other devices can record the electrical activity of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium
Potassium is a chemical element; it has Symbol (chemistry), symbol K (from Neo-Latin ) and atomic number19. It is a silvery white metal that is soft enough to easily cut with a knife. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, which is easily removed to create cation, an ion with a positive charge (which combines with anions to form salts). In nature, potassium occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac-flame color, colored flame. It is found dissolved in seawater (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiac Arrest
Cardiac arrest (also known as sudden cardiac arrest [SCA]) is when the heart suddenly and unexpectedly stops beating. When the heart stops beating, blood cannot properly Circulatory system, circulate around the body and the blood flow to the brain and other organs is decreased. When the brain does not receive enough blood, this can cause a person to lose consciousness and brain cells can start to die due to lack of oxygen. Coma and persistent vegetative state may result from cardiac arrest. Cardiac arrest is also identified by a lack of Pulse, central pulses and respiratory arrest, abnormal or absent breathing. Cardiac arrest and resultant hemodynamic collapse often occur due to arrhythmias (irregular heart rhythms). Ventricular fibrillation and ventricular tachycardia are most commonly recorded. However, as many incidents of cardiac arrest occur out-of-hospital or when a person is not having their cardiac activity monitored, it is difficult to identify the specific mechanism ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diabetes Insipidus
Diabetes insipidus (DI) is a condition characterized by large amounts of dilute urine and increased thirst. The amount of urine produced can be nearly 20 liters per day. Reduction of fluid has little effect on the concentration of the urine. Complications may include dehydration or seizures. There are four types of DI, each with a different set of causes. # Central DI (CDI), now known as arginine vasopressin deficiency (AVP-D), is due to a lack of vasopressin (antidiuretic hormone) production. This can be due to injury to the hypothalamus or pituitary gland or due to genetics. # Nephrogenic DI (NDI), also known as arginine vasopressin resistance (AVP-R), occurs when the kidneys do not respond properly to vasopressin. # Dipsogenic DI is a result of excessive fluid intake due to damage to the hypothalamic thirst mechanism. It occurs more often in those with certain psychiatric disorders or on certain medications. # Gestational DI occurs only during pregnancy. Diagnosis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water–electrolyte Imbalance
Electrolyte imbalance, or water-electrolyte imbalance, is an abnormality in the concentration of electrolytes in the body. Electrolytes play a vital role in maintaining homeostasis in the body. They help to regulate heart and neurological function, fluid balance, oxygen delivery, acid–base balance and much more. Electrolyte imbalances can develop by consuming too little or too much electrolyte as well as excreting too little or too much electrolyte. Examples of electrolytes include calcium, chloride, magnesium, phosphate, potassium, and sodium. Electrolyte disturbances are involved in many disease processes and are an important part of patient management in medicine. The causes, severity, treatment, and outcomes of these disturbances can differ greatly depending on the implicated electrolyte. The most serious electrolyte disturbances involve abnormalities in the levels of sodium, potassium or calcium. Other electrolyte imbalances are less common and often occur in conjunction ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T Waves
In electrocardiography, the T wave represents the repolarization of the ventricles. The interval from the beginning of the QRS complex to the apex of the T wave is referred to as the ''absolute refractory period''. The last half of the T wave is referred to as the ''relative refractory period'' or ''vulnerable period''. The T wave contains more information than the QT interval. The T wave can be described by its symmetry, skewness, slope of ascending and descending limbs, amplitude and subintervals like the Tpeak–Tend interval. In most leads, the T wave is positive. This is due to the repolarization of the membrane. During ventricle contraction (QRS complex), the heart depolarizes. Repolarization of the ventricle happens in the opposite direction of depolarization and is negative current, signifying the relaxation of the cardiac muscle of the ventricles. But this negative flow causes a positive T wave; although the cell becomes more negatively charged, the net effect is in th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cramp
A cramp is a sudden, involuntary, painful skeletal muscle contraction or overshortening associated with electrical activity. While generally temporary and non-damaging, they can cause significant pain and a paralysis-like immobility of the affected muscle. A cramp usually goes away on its own over several seconds or (sometimes) minutes. Cramps are common and tend to occur at rest, usually at night (nocturnal leg cramps). They are also often associated with pregnancy, physical exercise or overexertion, and age (common in older adults); in such cases, cramps are called idiopathic because there is no underlying pathology. In addition to those benign conditions cramps are also associated with many pathological conditions. Cramp definition is narrower than the definition of muscle spasm: spasms include any involuntary abnormal muscle contractions, while cramps are sustained and painful. True cramps can be distinguished from other cramp-like conditions. Cramps are different from mus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ST Segment
In electrocardiography, the ST segment connects the QRS complex and the T wave and has a duration of 0.005 to 0.150 sec (5 to 150 ms). It starts at the J point (junction between the QRS complex and ST segment) and ends at the beginning of the T wave. However, since it is usually difficult to determine exactly where the ST segment ends and the T wave begins, the relationship between the ST segment and T wave should be examined together. The typical ST segment duration is usually around 0.08 sec (80 ms). It should be essentially level with the PR and TP segments. The ST segment represents the isoelectric period when the ventricles are in between depolarization and repolarization. Interpretation * The normal ST segment has a slight upward concavity. * Flat, downsloping, or depressed ST segments may indicate coronary ischemia. * ST elevation may indicate transmural myocardial infarction. An elevation of >1mm and longer than 80 milliseconds following the J-point. This measure has a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PR Interval
In electrocardiography, the PR interval is the period, measured in milliseconds, that extends from the beginning of the P wave (the onset of atrial depolarization) until the beginning of the QRS complex (the onset of ventricular depolarization); it is normally between 120 and 200 ms in duration. The PR interval is sometimes termed the PQ interval. Interpretation Variations in the PQ interval can be associated with certain medical conditions: * Duration ** A long PR interval (of over 200 ms) indicates a slowing of conduction between the atria and ventricles, usually due to slow conduction through the atrioventricular node (AV node). This is known as first degree heart block. Prolongation can be associated with fibrosis of the AV node, high vagal tone, medications that slow the AV node such as beta-blockers, hypokalemia, acute rheumatic fever, or carditis associated with Lyme disease. ** A short PR interval (of less than 120ms) may be associated with a Pre-excitation synd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
