Sepsis/shock Flashcards
Three parts of cellular respiration
glycolysis,the citric acid cycle, and election transport chain
Mircrocirculation
the nexus between the arterioles and venules consisting of the capillaries the course between cells of the various orgons
% of oxygen bound, locations
97% hemoglobin
3%plasma
Oxygen carrying capacity formula
HgB 1.39= oxygen carrying capacity
Cao2 formula
Arterial oxygen content(Cao2) =(HgBx1.39xSao2)+(0.0031xPao2)
Normal value= 17-20 mL/100 mL aterial blood
DO2
Oxygen delivery
Combines arterial oxygen content with cardiac output
DO2=COxCao2
VO2
Oxygen consumption
VO2= COxHgbx13.9x(Sao2-Svo2)
Normal value 180-280 mL/min
ERo2
Oxygen extraction ratio
Vo2/Do2
Normal Value 25%
Factors that affect transport of blood
blood volume,viscosity, and arterial elasticity
Systolic blood pressure relies on
Cardiac output(the force and volume of bloodejected from the ventricles during systole
Cardiac output is dependent on
Heart rate and the components of stroke volume ( preload,afterload, and contractility
Diastolic blood presszure depends on
peripheral resistance, which is determined by ateriolar vasoconstriction
2,3 DPG
2,3 biphosphglycerate
a chemical that bings to deoxygenated Hgb which helps red blood cells relase oxygen
4 stages of shock
1,Initial (early shock)
2.Compensatory
3, decompnsatory or progressive
4. irreversible or refractory
Neural Compensation
Decreased cardiac output—-> Decreased blood pressure—->Sympathetic nervous system activation—->
Blood vessels (constriction of Integumentary system, renal system, and GI tract)
Skeletal muscle dilation,
coronary arteries dilation,
sweat glands diphoresis
heart increased rate
lungs increased rate and depth of respiration
pupils dilation
Hormonal compensation
Kidney
Decreased renal blood flow—->renin production—> release of aldosterone—-> sodium and water retention
Hypothalamus
- Posterior pituitary—-> release of ADH—-> sodium and water retention
- Anterior pituitary—-> release ofadrencorticotropic hormone—-> relase of cortisol—–> hyperglycemia
- Adrenal medulla—-> release of epi and norepi
Chemical compensation
Decreased cardiac output—-> decreased blood flow to lungs—–> increased physiologic dead space—->decreased arterial Pao2—->stimulates chemoreceptors—-> increased rate and depth of respirations/ increased PaCO2, increased sympathetic response—->Respiratory alkalosis—-> cerebral vasoconstriction—> cerebral ischemia—-> decreasedlevel of consciousness
Compensatory mechanisms are divided into
neural, hormonal, and chemical mechanisms
Capillary pressure is dependent on
adequate MAP
Marked change in hydrostatic pressure in microcirculation during progressive shock leads to
blood pooling due to increased hydrostatic pressure, and edema and third spacing (mottled skin)
CVP is a direct measure of
Right atrial pressure and an indirect measure of preload of the right ventricle
PCWP reflects
Left atrial pressure
Primary MODS
Results from direct insult such as trauma
Secondary MODS
is the more common cause of organ failure and is slower, more progressive insult to organs
Frequently results from the sepsis cascade
Mortality rates with MODS
2 failing organs are 22 to 33% chance of recovery
4 or more organs the mortality rate is nearly 100%
Renal failure increases the risk of death by what percent
30%
Classifications of shock
Cardiogenic, hypovolemic, and distributive
Cardiogenic shock
failure of the heart to pump blooc effectively
A sustained systolic blood pressure of 80 to 90 mmhg for greater then 30 min
A MAP of 30 mmhg below baseline or less then 65 mmhg over time
a severe reduction in cardiac index(18mmhg or right ventricular fillingpressure of >10 to 15 mmhg
5 major determinants of myocardial oxygen consumption
contractility,preload,wall tension,afterload,and heart rate
Primary management of cardiogenic shock is focused on
enhancing CO while decreasing left ventricular workload
Findings ins Left ventricular heart failure
Heart rate: Increased Blood pressure:WNL initial, decreased with severity Pulse pressure:narrow CVP:WNL PCWP:increased CO/CI:decreased SVR:increased Svo2:decreased Urinary output:decreased JVD:absent Heart sounds:S3 Edema:pulmonary
Findings in right ventricular heart failure
Heart rate: Increased Blood pressure:WNL initial, decreased with severity Pulse pressure:narrow CVP: Increased PCWP:decreased CO/CI:decreased SVR:increased Svo2:decreased Urinary output:decreased JVD:present Heart sounds:normal Edema:Peripheral
Findings in Biventricular Heart Failure
Heart rate: Increased or decreased Blood pressure:Decreased Pulse pressure:narrow CVP: Increased PCWP:Increased CO/CI:decreased SVR:increased Svo2:decreased Urinary output:decreased JVD:present Heart sounds:S3 or S4 Edema:systemic
Findings in hypovolemic shock
Heart rate: Increased Blood pressure:WNL initial, decreased with severity Pulse pressure:narrow CVP: decreased PCWP:decreased CO/CI:decreased SVR:increased Svo2:decreased Urinary output:decreased JVD:flat Hct:Decreased with hemmorage/ increased with dehydration
Class I hemmorage 70 kg male
blood loss(ml):30 Fluid replacement:crystalloid
Class II hemmorage 70 kg male
blood loss(ml):750-1500 %blood loss:15-30 HR:.>100 blood pressure:Normal pulse pressure:Narrow Cap Refill:delayed RR:20-30 CNS:mildly anxious Skin:cool,pale Urine output:20-30 Fluid replacement:crystalloid
Class III Hemmorage 70 kg male
blood loss(ml):1500-2,000 %blood loss:30-40 HR:>120 blood pressure:Low pulse pressure:Narrow Cap Refill:delayed RR:30-40 CNS:anxious and confused Skin:cold,pale, moist Urine output:5-15 Fluid replacement:crystalloid and blood
Class IV hemmorage
blood loss(ml):>2000 %blood loss:>40 HR:>140 blood pressure:low pulse pressure:very narrow Cap Refill:absent RR:>35 CNS:confused and lethargic Skin:cold,cyanotic Urine output:minimalor none Fluid replacement:crystalloid and blood
