Midterm Study Guide: Cardiac & ABGs Flashcards
two types of hypovolemic shock
Absolute and Relative
Absolute shock:
decreased preload from volume loss of circulating blood
Relative shock:
decreased preload d/t increase in the capacity of blood vessels to sequester blood volume away from the heart
four stages of schock
initial, compensatory, progressive, refractory
initial stage: what does this look like
*usually not clinically apparent
*metabolism changes at cellular level from aerobic (w/o2) to anaerobic (w/o o2) depriving the cells of oxygen
*causes lactic acid to build up and must be removed by the liver which requires o2, but o2 is unavailable d/t decreased tissue perfusion
Compensatory stage
During the compensatory stage of shock, the body tries to maintain blood pressure and organ perfusion by activating compensatory mechanisms. (increase heart rate, constricting blood vessels to redirect blood flow to vital organs)
Progressive (what has failed)
*Compensatory stage has failed
*CO decreases and BP decreases
*Anasarca (diffuse profound edema) decreasing blood flow to the pulmonary capillaries
*Hypoperfusion leads to ischemia of distal extremities
*complete deterioration of the cardiac system and thus all organ systems
Refractory stage
the body’s organs and tissues fail to receive sufficient oxygen and nutrients. Blood pressure remains critically low, and vital organs sustain irreversible damage, often leading to multi-organ failure and death
Hypovolemic shock def
inadequate intravascular vol leading to decreased tissue perfusion
*MOST COMMON FORM OF SHOCK
Patho of hypovolemic shock
loss of circulating fluid vol -> decrease in venous return -> decrease in preload -> decrease in CO and SV -> inadequate cellular o2 supply -> ineffective tissue perfusion
Absolute fluid loss through… (5)
*hemorrhage
*GI loss (v/d)
*fistula drainage
*DM
*Diuresis
(ex. trauma patients)
Relative fluid loss though… (3)
*fluid moves out of the vascular space into extravascular space
*intracativity space
*third spacing - fluid leaking from vascular space to interstitial space
(ex. burn patients)
Classifications of hypovolemic shock (4)
1: 15-20% vol loss (750mL)
2: 15-30% vol loss (750-1500mL)
3: 30-40% vol loss (1500-2000mL)
4: >40% vol loss (>2000mL)
S/S of hypovolemic shock (6)
*high HR
*norm to low BP
*Low CO (amount of blood pumped in 1 min) & CI (measure of CO per square meter of body surface)
*CVP (measure of BP in central veins)/wedge low
*SVR(resistance the arteries present to flow of blood) low
*UO low
RN interventions for hypovolemic shock: (8)
*enhance vol replacement
*minimize fluid vol loss
*maintain optimal cardiac contractility and CO
*maintain optimal o2 sats
*control body temp
*prevent injury caused by decreased perfusion
*maintain nutrition status
*maintain renal perfusion
RN interventions for hypovolemic shock: enhance vol replacement (2 + what type of volume)
*2 large bore IV caths: 18g+
*Volume!
1. crystalloids: isotonic saline 3ml for every 1ml lost
2. Hypotonic saline: when Na is high
3. warm fluids
4: colloids: albumin
5.Blood and blood product: increase o2 carrying capacity
RN interventions for hypovolemic shock: Minimizing vol loss (4)
*compression of compressible vessels
*surgery to control bleeding
*antidiarrheals
*blood transfusions
RN interventions for hypovolemic shock: maintain optimal cardiac contractility and CO (4)
*PA line readings Q1hr (best measure of pressure w/i the pulmonary artery
*Dobutamine for CO
*NaHCo3 if pH <7.0
*Hourly I&Os
RN interventions for hypovolemic shock: maintain optimal o2 sat (3)
*keep SpO2 >95% (start 5-6L/min NC)
*intubation is likely (monitor ABGs)
*Maintain bedrest and adequate rest periods
RN interventions for hypovolemic shock: control body temp (2 + why)
(why: overheating increases myocardial o2 consumption)
*tx hyperthermia w/ cooling blankets
*warm IV fluids
RN interventions for hypovolemic shock: Prevent injury caused by decreased perfusion (4)
*limit sedatives
*give meds through central line
*monitor cap refill
*monitor s/s of skin breakdown
RN interventions for hypovolemic shock: Maintain nutrition status (2)
*Enteral feeding tube
*monitor electrolytes
RN interventions for hypovolemic shock: maintain renal perfusion (5)
*insert FC and monitor I&Os
*monitor renal labs (BUN, Creat, etc)
*replace vol
*monitor urine color
*dobutamine: increases perfusion
What will a hypovolemic shock pt look like? (7)
*pale, cool skin
*weak or rapid pulse
*decreased BP
*altered LOC
*thirst
*anxiety/restlessness
*N/V
sepsis
systematic inflam response to infection
Severe sepsis
sepsis complicated by organ dysfunction
Septic shock
Presence of sepsis complicated by organ dysfunction
Septic shock:
presence of sepsis with hypotension despite fluid resuscitation -> inadequate tissue perfusion resulting in hypoxia
Septic shock factors (2)
*Intrinsic factors: internal or inherent qualities or characteristics
*Extrinsic factors: external influences or environmental conditions that impact an organism
Examples of intrinsic factors leading to septic shock (2)
*extreme age
*coexisting diseases: ex. burns, cancer, substance abuse, malnutrition, etc
Examples of extrinsic factors leading to septic shock (6)
*invasive devices
*med therapy
*fluid therapy
*surgical or trauma wounds
*surgical or invasive diagnostic procedures
*immunosuppressive therapy (chemo)
septic shock patho:
infection -> immune response -> inflamm -> HoTN -> decreased perfusion -> cellular damage -> impaired cellular metabolism
3 major patho effects of septic shock
*vasodilation
*maldistribution of blood flow
*myocardial dysfunction: decreased EF, ventricular dilation
s/s of septic shock (7)
*increased HR
*HoTN
*full bounding pulse
*pink, warm, flushed and then cold (warm better than cold sepsis)
*first increased RR then decreased RR
*decreased UO
*increased temp
What are ART lines used for and not used for? (3)
*Best continuous BP monitoring & Assessment of arterial waveforms: give info about cardiac status
*Blood sampling: ABG
*NOT used for giving fluids or drugs
Why do we measure arterial blood pressure through the ART line?
Most accurate and reliable measurement and available quickly