| A | B |
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| shock | a state of inadequate tissue perfusion |
| water | the universal solvent. Approximately 60 percent of the weight of the human body is due to water |
| intracellular fluid (ICF) | portion of the body fluid inside the body's cells |
| extracellular fluid (ECF) | portion of the body fluid outside the body's cells |
| intravascular fluid | portion of the body fluid outside the body's cells and within the circulatory system |
| interstitial fluid | portion of the body fluid found outside the body's cells, yet not within the circulatory system. Interstitial fluid is that fluid found within the interstitial space between the cells |
| electrolytes | chemical substances that dissociate into charged particles when placed in water |
| ion | a charged particle |
| cation | a postively charged ion. It is attracted to the negative pole of an electrode (cathode), hence the name. |
| anion | a negatively charged ion. It is attracted to the positive pole of an electrode (anode), hence the name. |
| soduim | Is the most prevalent cation in the extracellular fluid. It plays a major role in regulating water distribution |
| potassium | Is the most prevalent cation in the intracellular fluid. It is also important in electrical impulse transmission |
| calcium | has many physiological functions. It plays a major role in muscle contraction as well as nervous impulse transmission |
| magnesium | necessary for several biochemical processes. It is also closely associated with phosphate in many body processes |
| chloride | is an important anion. It also plays a major role in fluid balance and renal function |
| bicarbonate | is the principle buffer of the body. It neutralizes the highly acidic hydrogen ion and other organic acids |
| phosphate | is important in body energy stores. It also acts as a buffer, primarily in the intracellular space |
| buffer | substance that neutralizes or weakens a strong acid or base |
| semi-permeable membrane | specialized biological membrane, such as that which encloses the body's cells, that allows the apssage of certain substances and restricts the passsage of others |
| solute | a substance that dissolves in a solvent |
| solvent | a liquid that dissolves a solute |
| isotonic | a state where solutions on opposite sides of a semi-permeable membrane are in equal concertration |
| hypertonic | a state where a solution has a higher solute concentration on one side of a semipermeable membrane compared to the other side |
| hypotonic | a state where a solute has a lower solute concentration on one side of a semipermeable membrance compared to the other side |
| diffusion | the movement of solutes (substances dissolved in a solution) from an area of greater concentration to an area of lesser concentration |
| osmosis | the movement of a solvent (water) across a semi-permeable membrance from an area of lesser (solute) concentration to an area of greater (solute) concentration. Osmosis is a form of diffusion |
| active transport | biochemical process where a substance is moved across a cell membrane, often against a gradient, using energy |
| facilitated dissusion | biochemical process where a substance is slectively transported acrosee a membrane, using "helper proteins" and energy |
| hemoglobin | the iron-containing substance in blood responsible for transport of oxygen |
| hematocrit | the percentage of the blood consisting of the red blood cells, or erythrocyes (usually 35-45 percent) |
| ABO system | system of blood typing based on the presence of proteins on the surgace of the red blood cells. |
| homeostasis | the body's natural tendency to keep the internal environment constant |
| dehydration | an abnormal decrease in total body water |
| overhydration | an excess of total body water |
| fluid replacement therapy | intravenous therapy is the introduction of fluids and other substances into the venous side of the circulatory system. Intravenous therapy is used for fluid replacement, for electrolyte replacement, and for the introduction of medications directly into the cardiovascular system |
| colloids | contain proteins, or other high molecular weight molecules, that tend to remain in the intravascular pace for an extended period of time |
| colloid osmotic pressure | pressure generated by the presence of colloids in the vascular system or interstitial space |
| plasma protein fraction (plasmanate) | is a protein containing colloid |
| salt-poor albumin | contains only human albumin. Each gram of albumin holds approximately 18 milliliters of water in the blood stream |
| dextran | is not a protein, but a large sugar molecule with osmotic properties similar to albumin |
| hetastarch (hespan) | is a sugar molecule with osmotic properites similar to protein. It does not appear to share many of Dextran's side-effects |
| albumin | protein found in almost all animal tissues hat constitutes one of the major proteins in human blood |
| crysalloids | are the primary solutions used in prehospital intervenous fluid therapy |
| tonicity | the number of particles present per unit of volume |
| isotonic solutions | have an electrolyte composition similar to blood plasma. When placed into a normally hydrated patient, they will not cause a significant fluid or electrolyte shift |
| hypertonic solutions | have a higher solute concentration than plasma. When administered to a normally hydrated patient, these fluids will tend to casue a fluid shift out of the intracellular compartment into the extracelluar compartment. Later, there will be a dissusion of solute in the opposite direction |
| hypotonic solutions | have less of a solute concentration when compared to plasma. When administered to a normally hydrated pateint, they will cause movement of fluid from the extracellular compartment into the intracellular compartment. Later, sloutes will move in an opposite direction |
| selection of replacment fluid | normal saline and lactated ringer's solution are the most commonly-used fluids in prehospital care. |
| lactated ringer's | is an isotonic, electrolyte solution. It contains sodium chloride, potassium chloride, calcium chloride, and sodium lacate in water |
| normal saline | is an electrolyte solution containing sodium chloride in wahter. It is isotonic with extracellular fluid |
| five percent dextrose in water D5W | is a hypotonic, glucose solution used to keep a vein open and to supply calories necessary for metabolism |
| pH | scientific method of expressing the acidity or alkalinity of a solution. It is the logarithm of the hydrogen ion concentration divided by one. The higher the pH, the more alkaline the solution. The lower the pH, the more acidic the solution |
| acidosis | a state where the pH is lower than normal to an increased hydrogen ion concentration |
| alkalosis | a state where the pH is higher than normal due to the decreased hydrogen ion concentration |
| acid-base balance | is a dynamic relationship that reflects the relative concentration of hydrogen ions in the body |
| bicarbonate buffer system | is a fast-acting biochemical system that minimizes any significant shift in the body's pH. |
| respiratory system | helps control the body's pH by retaining or eliminating carbon dioxide |
| kidneys | plays a role in maintaining acid-base balances. when the hydrogen ion concentraton varies from normal, the kidneys excrete either an alkaline or acidic urine |
| disorders of acid-base balance | in some cases, the pH of the body will move beyond the normal range of 7.35 to 7.45. This may be due to eight respiratory or metabolic casues. The acid-base disorder is named according to its origin. |
| respiratory alkalosis | is caused by hyperventilation. Carbon dioxide is eliminated, resulting in the lost of hydrogen ions and an increased pH. |
| respiratory acidosis | is due to hproventilation and the retention of carbon dioxide. The condition increses the concentration of hydrogen ions, which in turn lowers the pH. |
| metabolic acidosis | is a condition that results from the accumulation of metabolic acids, such as lactic acid. In low perfusing states, such as shock, oxygen is not supplied to the tissues in adequate quantities to meet the metabolic demands of the cells. In the absence of oxygen, cells use alternate sources of energy to survive. This results in incomplete metabolism and an accumulation of acids and toeht toxic by-products |
| metabolic alkalosis | is result of the accumulation of an excess of bicarbonate ions. This can occur throught he intake of excessive bicarbonate through the ingestion of large amounts of antacids. It also occurs in prolonged vomiting and diarrhea |
| perfusion | fluid passing through an organ or a part of the body |
| physiology of perfusion | all body cells require a constant supply of oxygen and otehr essential nutrients. At the same time, waste products, cush as carbon dioxide, must be constantly removed. |
| pathophysiology of shock | shock is defined as inadequate tissue perfusion. It can occur for many reasons such as trauma, fluid loss, heart attack, infection, spinal cord injury, and other causes. Although casues differ, all forms of shock have the same underlying pathophysiology at the tissue level. |
| preload | the pressure within the ventricles at the end of the diastole |
| cardiac contractile force | the force generated by the heart during each contraction |
| afteload | the resistance against which the heart must pump |
| peripheral vascular resistance | the resistance to blood flow due to the peripheral blood vessels. This pressure must be overcome for the heart to pump blood effectively |
| cardiac output | the amount of blood pumped by the heart in one minute |
| the pump | the heart is the pump of the cardiovascular system |
| the fluid | blood is the fluid of the cardiovascular system |
| the container | blood vessels serve as the contain of the cardiovascular system |
| oxygen transport | peripheral tissue oxygenation is also essential. Oxygen is brought into the body via the respiratory system |
| "fick principle" | adequate concentration of inspired oxygen; appropriate movement of oxygen across the alveolar/capilary membrane into the pulmonary bloodstream; adequate number of red blood cells to carry the oxygen; proper tissue perfusion; effecient off-lading of oxygen at the tissue level |
| stages of shock | shock can be divided into three distinct stages: Compenstated shock; decompensated shock and irreversible shock |
| compensated shock | As serious hemorrhage, fluid loss, or dehydration occurs, vascluar volume decreases. Several compensatory mechanisms ave activated to mantain adequate perfusion to critical organs. If volume loss continues, the body will be unable to maintain blood pressure and perfusion. The patient will then move into decompensated shock |
| decompensated shock | the hallmark of decompensated shock is a fall in the blood pressure |
| irreversible shock | when enough cells in vital organs are disrupted, shock becomes irreversible and death is inevitable, even if perfusion and vital signs are restored |
| types of shock | although all types of shock result in inadequate tissue perfusion, the causes are different. Shock is commonly classified based on the cause. |
| hypovolemic shock | shock due to a loss of intravascular fluid volume - internal or external hemorrhage, trauma, severe dehydration from vomiting or diarrhea, plasma loss from burns, diabetic ketoacidosis with resultant osmotic diuresis, excessive sweating |
| cardiogenic shock | an inability of the heart to pump enough blood to supply all body parts. Usually the result of severe left ventricular failure, secondary to acute myocardial infarction or congestive heart failure. |
| neurogenic shock | inadequate peripheral resistance due to widespread vasodilation. With this inappropriate vasodilation, a disproportionate amount of blood collects in the capillary bed. This reduces venous return, cardiac output, and arterial blood pressure. This type of shock is most commonly due to an injury that resluts in severe spinal cord injury or total transection of the cord. Other causes are head injury, septicemia from bacterial nfection, anaphylactic reaction, insulin overdose and addisonian crisis (a disorder of the adrenal glands) With neurogenic shock, there is an absence of the "compensatory response". |
