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Terms in this set (34)

*Homeostatic regulation is maintained primarily by the cardiovascular system and depends on 4 components:
1. cardiac output that meets body requirements
2. uncompromised vascular system in which vessels can allow sufficient blood flow and gave good tne
3. volume of blood to fill circulatory system, and blood pressure to maintain blood flow
4. tissues that are able to use oxygen

Hemodynamics:
-stroke volume: amount of blood pumped into the aorta with each contraction, into the left ventricle
-SVR (sympathetic tone)
-Cardiac Output: amount of blood pumped into aorta each min (SV X HR)
-MAP (mean arterial pressure) is product of cardiac output and SVR (CO X SVR)
-MAP of 70-110 is normal MAP of 60 is required to maintain adequate perfusion to the brain, heart, and kidneys
-shock is triggered by a sustained drop in MAP

-perfusion of the lungs diminish, CO2 is retained, and respiratory acidosis occurs
-complications can occur from decrease perfusion of the lungs known as respiratory distress syndrome (ARDS), or shock lung
-ARDS causes: hemorrhage, severe allergic responses, trauma, and infection
-gastric ulcers can develops from severe trauma, sepsis, or burns
-GI motility is impaired and paralytic ileus may result
-liver functions can become impaired causing hypoglycemia
-early neuro changes include apathy and lethargy that can progress to coma
-common early s/s of cerebral hypoxia is restlessness
-urine output is reduced and is highly concentrated
-oliguria <20mL per hr indicates progressive shock
-healthy kidneys can tolerate a drop in perfusion for about 20 min, then acute tubular necrosis develops (causes renal failure)
-skin of Caucasians become pale
-shock in dark colored pts include paleness of the lips, oral mucous membranes, nail beds, and conjunctiva
-skin is cool and moist
-skin in later stages often is edematous
-body temp decreases
-pts can become thirsts (due to decreased blood volume and increased serum osmolality)
-decrease in intravascular volume of >15%
-decrease in SV, CO, BP
-decrease in stroke volume, cardiac output, and blood pressure
-most common type and often occurs with other types\
-there is a drop in blood pressure
-heart rate and vasoconstriction increases
-shock can be reversed with fluid loss <500mL
-shock progresses with blood volume >1000mL
-*when BP decreases, lay HOB down, when BP increases, lay HOB up
-seen in pts who have had surgery, burns, and traumatic injuries

Causes:
-hemorrhage (surgery, trauma, GI bleeding, blood coagulation disorders, ruptured esophageal varices)
-loss of intravascular fluid (burns)
-loss of intravascular volume (severe dehydration)
-Loss of GI fluid due to persistent and severe vomiting, diarrhea, continuous nasogastric suctioning
-renal losses of fluid from diuretics or endocrine disorders (diabetes)
-conditions causing fluid shifts from intravascular compartment to the interstitial space
-third spacing due to liver diseases with ascites, pleural effusion, or intestinal obstruction

Older Adults:
-atherosclerosis affects organs sensitivity to the slightest reduction in blood flow
-risk factors: chronic diuretic use or malnutrition which causes secondary volume depletion
-beta blockers may not present with tachycardia as an early indicator of shock
-elderly pts require early invasive monitoring

Assessment Findings:
-drop in BP, look for cause (blood, surgery, fluid, diuretics, GI, NV)

Nursing Care:
-monitor fluid status
-I&O (urine, vomit, wound drainage, gastric drainage, chest tube drainage)
-measure fluid losses
-*for blood loss pts (priority give blood)
-several types of shock that results from widespread vasodilation and decreased peripheral resistance
-as blood volume does not change, relative hypovolemia results
-*EX of distributive shock: septic, neurogenic, and anaphylactic shock
-*unlike hypovolemic and cardiogenic shock; in septic shock cardiac output is high and systemic vascular resistance is low
-toxins damage small blood vessels first such as small blood vessels of the kidneys and lungs the most
-formation of blood clots is high
-hypovolemia results
-early and late phase
-early (warm phase): weakness, and warm, flushed skin, high fever/chills
-late (cold phase): typical shock s/s such as cold, moist skin, oliguria, changes in mental status
-death caused from resp failure, cardiac failure, renal failure

Septic Shock:
-leading cause of death fro pts in ICU
-part of progressive syndrome known as systemic inflammatory response syndrome (SIRS)
-caused by gram neg (E.coli) and gram pos (Staph/Strep) bacteria
-Foley catheters #1 cause
-diabetics at risk

Risk Factors:
-pts that are hospitalized, debilitating chronic illnesses, poor nutritional status, and invasive procedures or surgery, older adults, immunocompromised

Portals of entry:
-urinary system (catheters), respiratory system (suctioning, aspiration, tracheostomy, endotracheal tubes, resp therapy, ventilators), GI system (peptic ulcers, ruptured appendix, peritonitis), Integumentary system (wounds, IV catheters, ulcers trauma, burns), Female reproductive system (abortions, tampon use, STDs)

Complications:
-toxic shock syndrome: occurs mainly in menstruating women who use tampons. Manifestations: hypotension, hyperpyrexia, headache, myalgia, confusion, skin rash, vomiting and diarrhea
-disseminated intravascular coagulation (DIC): generalized response to injury. There is simultaneous bleeding and clotting. As clotting factors are depleted, generalized bleeding begins.

Nursing Care:
-careful/consistent hand washing
-aseptic technique
-monitor all sites following invasive procedures
-monitor for local/systemic s/s of infection (WBC count)
-maintain a patent airway (all pts in shock; even those with adequate respirations, should receive O2 therapy)
-pt can receive oxygen by mask or nasal cannula to maintain the PaO2 > 80mmHg during the first 4-6 hrs

-CVP may be used to differentiate dx of shock and to provide info about the heart
-pulmonary artery catheter may be inserted to monitor cardiac function, fluid balance, and effects of vasoactive medications

-the most effective treatment for the pt in hypovolemic shock is administration of IV fluids or blood
-the pt with cardiogenic shock may require either fluid replacement or restriction, depending on pulmonary artery pressure
-fluids administered via 2 large bore peripheral lines or though a central line
-*fluid resuscitation protocols include: rapid crystalloid infusion follow by blood transfusion. Crystalloids and colloid solutions increase blood volume and tissue perfusion. Whole blood or blood products increase the oxygen carrying capacity of the blood and this increases oxygenation of the cells (these resuscitation fluids are not thought to minimize inflammation)

-assess/monitor cardiovascular function via BP, heart rate, pulse ox, peripheral pulses, hemodynamic monitoring of arterial pressure and CVPs
-if peripheral pulses and BP are lost, insert a arterial venous, and pulmonary artery catheter to establish progression of shock and evaluate pts response to therapy
-measure I&O
-monitor bowel sounds, distention, and abdominal pain (paralytic ileus)
-monitor for sudden sharp chest pain, dyspnea, cyanosis, anxiety, and restlessness (pulmonary emboli)
-place in supine position with head elevated to about 10 degrees, and legs elevated to about 20 degrees, trunk flat, and head and shoulders elevated higher than chest (this position should not be used for pts in cardiogenic shock)
-neck veins that cannot be seen when the pt is in the supine position indicate decreased intravascular volume
-CVP determines fluid status and will be low in hypovolemic shock
-normal CVP: 5-14cmH2O or 2-6 mmHG
-monitor output via Foley hourly (urine output is a reliable indicator of renal perfusion)

Medications:
-when fluids alone are not enough, vasoactive drugs (causes vasoconstriction/vasodilation) and inotropic drugs (improves cardiac function) are administered
-diuretics: increase output after fluid replacement has started
-sodium bicarbonate: treats acidosis
-calcium: replace calcium lost from blood transfusions
-antiarrhythmics: stabilizes heart rhythm
-broad spectrum antibiotics: suppress organisms that cause septic shock
-epinephrine, antihistamines, and inhaled beta 2 agonists (treats anaphylactic shock)
-morphine: dilates veins and decreases anxiety