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9/14/14
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Differen,a,ng And Trea,ng Shock States
1st Annual ENA Conference-‐ABQ,NM Ann Whitehead RN CCRN-‐CMC-‐CSC, CEN
Defining Shock
An acute, widespread process of impaired ,ssue perfusion that results in cellular, metabolic and hemodynamic derangements.
How Does The Body React to Shock?
• Compensatory Responses • The reason for most of the symptoms observed in shock pa,ents
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Heart Rate
• What is it trying to achieve? • Maintenance of ,ssue perfusion by maintaining cardiac output
• CO = SV x HR • What is stroke volume? • What affects stroke volume?
Stroke Volume Influenced By: • Fluid status • Contrac,lity of the heart • Valvular disease • Ventricular Compliance • AYerload • Drugs
Fluid Status: Preload
The amount of blood in the right or leY ventricle at end-‐diastole
RVEDV or LVEDV
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Fluid Status • Increased fluid status will increase the preload. – Volume administra,on, blood administra,on, renal failure
• Decreased fluid status will decrease preload – Diure,cs, blood loss, sepsis, endocrine issues, nitroglycerine, morphine
Contrac,lity
• Starling’s Law: é volume = é stretch of cardiac muscle fibers = é contrac,lity
• Eventually the myocardial fibers get overstretched and cannot contract anymore = overworked elas,c
Contrac,lity
• Some drugs and electrolytes é contrac,lity: – +Inotropes-‐ Dopamine, Digoxin, Dobutamine, Amrinone, Milrinone, Epinephrine
– Magnesium, Calcium, Potassium – é Circula,ng Catecholamines, SNS s,mula,on, Adrenaline
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Factors That Decrease Contrac,lity
• Hypoxia • Acidosis • Electrolyte imbalances • Anesthesia • Cardiomyopathy • Myocardial infarc,on or ischemia • Drugs: Beta blockers, Calcium channel blockers
Valvular Disease
• Structural or func,onal abnormali,es of single or mul,ple cardiac valves which results in altera,on of blood flow across the valve.
• Two types: – Steno,c-‐ progressive narrowing of the valve orifice-‐ affected chamber becomes hypertrophied
– Regurgitant-‐ (Insufficient) retrograde blood flow back into origina,ng chamber causing it to dilate
Decreased Ventricular Compliance
• Diastolic Dysfunc,on-‐ occurs when the LV cannot relax usually due to scar forma,on post MI
• The heart is non-‐compliant and cannot fill properly
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Decreased Ventricular Compliance • Occurs when heart is prevented from expanding normally during ventricular filling:
– é Intrathoracic pressure (peep, pneumothorax) – é Pericardial pressure (tamponade) – é Pressure/volume of other ventricle – Myocardial ischemia or disease – Ventricular hypertrophy
Systemic Vascular Resistance (SVR)
• The resistance the ventricles must pump against in order to empty
• Systemic vascular resistance-‐SVR-‐ is indicator of leY ventricular
aYerload
Blood Pressure Compensatory Mechanisms to Maintain AYerload
• ↓ MAP → Baroreceptors ac,vate alpha and beta receptors-‐ the sympathe,c response.
• ↑ Circula,ng Catecholamines • Alpha = aYerload Beta = beat • ↑ AYerload → vasoconstric,on → ↓ pulse pressure, ↓ perfusion to skin, gut and other non-‐core organs
• ↑ HR → Sinus Tachycardia • ↑ Contrac,lity
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Respiratory Compensatory Mechanisms
• Maintaining ,ssue oxygena,on is cri,cal • Increased rate and depth of respira,ons • Nasal flaring and accessory muscle u,liza,on • Pulmonary vasodila,on to increase blood flow to the lungs
Renal Compensatory Mechanisms
• Ac,va,on of the RAAS-‐Renin-‐angiotensin-‐aldosterone system
• JGA -‐ juxtaglomerular apparatus-‐ ( a group of specialized cells in the afferent arteriole of the kidney) is ac,vated 2° ↓ GFP
• JGA synthesizes, stores and releases renin • Renin enters circula,on → Angiotensin I • Angiotensin I converts to Angiotensin II
Renal Compensatory Mechanisms
• Angiotensin II -‐ powerful vasoconstrictor -‐ causes a great ↑ in SVR and BP
• Angiotensin II s,mulates the release of Aldosterone-‐ ↑’s reabsorp,on of Na from the distal tubule
• ↑ Circula,ng Volume and a potent vasoconstric,on → ↑ SVR
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Basically Four Types of Shock
• Hypovolemic • Distribu,ve • Cardiogenic • Obstruc,ve
Hypovolemic Shock
• Occurs from inadequate fluid volume in vascular space
• Decreased ,ssue perfusion • Most common form of shock
Hypovolemic Shock-‐Pathophysiology
• Loss of circula,ng fluid volume → ↓venous return → ↓ end-‐diastolic volume (preload) → ↓ CO → ↓ cellular oxygen supply and ineffec,ve ,ssue perfusion.
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Hypovolemic Shock Signs and Symptoms
• Class I-‐ volume loss of 15% (750 ml)-‐ HR<100 • Class II-‐ volume loss of 15 -‐30% (750-‐1500ml) HR>100, BP nl. with narrowed pp, ↑ resp. rate and depth, slight ↓ UOP, cool and pale skin, some LOC changes (restless, anxious)
• Class III-‐ vol. loss of 30-‐40% (1500-‐2000 ml) – HR > 120, resp distress, ↓ BP, UOP, LOC-‐confused, skin cold and clammy
• Class IV-‐ vol. loss of > 40% ( > 2 liters) – HR >140, ↓ ↓ BP, no UOP, profound MOF, mouled skin, LOC-‐unresponsive
Treatment
• Minimize further fluid loss (treat cause) • Aggressive administra,on of warmed fluid
and/or blood and blood products. • O-‐ is universal donor, may use O+ if no O-‐ (85 % of white and 95% of black pop is Rh+) • Replace FFP and platelets as needed • Calcium administra,on
Distribu,ve Shock
Three types 1. Sep,c 2. Anaphylac,c 3. Neurogenic
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Sep,c Shock
• Occurs when microorganisms invade the body ini,a,ng a complex systemic response that s,mulates inflammatory and immune responses
Sep,c Shock • Release of toxins in the blood stream ac,vate an immune system response as well as a clovng cascade response
• The immune system becomes overwhelmed and feedback systems fail
• The result is clumps of white blood cells and platelets clogging up the blood vessels
• Also the mediator response damages the vascular integrity of the capillaries increasing capillary permeability and leaking of intravascular fluid into the extravascular space
Sep,c Shock
• Massive peripheral vasodilata,on occurs, microemboli forma,on, selec,ve vasoconstric,on and increased capillary membrane permeability
• Major disrup,on to blood flow occurs followed by loss of cellular oxygen supply, ,ssue hypoxia and ,ssue death
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Sep,c Shock-‐Signs and Symptoms
• Massive vasodilata,on → ↓ SVR → ↓ circula,ng volume → ↓ SV → ↑ HR, ↑CO/CI, ↓ BP, ↑ resp rate and hypoxia occur due to pulmonary vasoconstric,on and microemboli forming in pulmonary vasculature, ↓ LOC because of ↓ cerebral perfusion, ↓ UOP, ↑ WBC,
↑ lactate levels due to hypoxia → metabolic acidosis
Treatment of Sep,c Shock • Administer an,bio,cs quickly aYer BC x 2 – use procalcitonin levels (or similar biomarkers) to determine if bacterial cause
• Aggressive fluid resuscita,on-‐target CVP > 8 and 8-‐12 in ven,lated pa,ents • Support BP with vasopressors (NE first) • Op,mize oxygena,on and ven,la,on-‐intubate-‐low ,dal volumes: 6 mL/kg
• Monitor lactate level (nl 1-‐2 mmol) • Maintain glucose in good control: <180 mg/dl • Low dose steroids for retractable hypotension (adrenal suppression) (no ACTH tests)
Fluid Resuscita,on Pearls
• Fluid challenge is con,nued as long as there is hemodynamic improvement either based on dynamic (eg. change in pulse pressure, SV varia,on) or sta,c (eg. BP & HR) variables
• Crystalloids are first fluids of choice may add Albumin in severe sepsis. No heta or pentastarches = renal impairment
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Vasopressor Pearls
• AYer full fluid resuscita,on (CVP 8-‐12) start NE (Levophed); target MAP > 65
• May add Epinephrine or Vasopressin drips as second line pressor.
• May add Dobutamine drip if myocardial dysfunc,on suspected
Other Pearls
• Transfuse for Hb < 7 in pts without myocardial ischemia, severe hemorrhage or severe hypoxemia
• VAP protocols and low TV ven,la,on (6ml/kg) • DVT prophylaxis • Protocolized glucose control-‐target < 180 mg/dl • No rou,ne use of Bicarb for acidemia • Stress ulcer prophylaxis: PPI over H2 Blockers
Anaphylac,c Shock
• An an,body-‐an,gen response that leads to the release of biochemical mediators and histamine response causing massive vasodilata,on and ↑ capillary permeability, inflamma,on and bronchoconstric,on
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Anaphylac,c Shock-‐ Signs and Symptoms
• Start within minutes of exposure • Cutaneous-‐ Pruri,s, redness, ur,caria, angioedema
• LOC-‐ Anxious, restless, hot, apprehensive • Resp-‐ Laryngeal edema, stridor, wheezes • CV-‐ Massive vasodilata,on → ↓ SVR → ↓ circula,ng volume → ↓ SV → ↑ HR, ↓ BP, ↓ CO
Anaphylac,c Shock-‐Treatment
• Immediate removal of cause-‐ if known • Epinephrine to promote bronchodila,on and vasoconstric,on
• Benadryl to block histamine response • Cor,costeroids to stabilize capillary membranes • Support oxygena,on • Administer fluid resuscita,on • Vasoconstric,ve agents
Neurogenic Shock
• Loss of sympathe,c tone resul,ng in massive peripheral vasodila,on, impaired thermal regula,on and inhibi,on of the baroreceptor response
• Rarest form of shock
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Neurogenic Shock-‐Causes
• Usually due to SCI above T 6-‐ Spinal shock • Spinal anesthesia • Drugs • Emo,onal stress • Pain • CNS dysfunc,on
Neurogenic Shock-‐ Signs and Symptoms
• Heart rate slows due to increased parasympathe,c control → ↓ CO
• BP drops due to loss of vasomotor tone → ↓ SVR and SV • Warm, dry skin with hypothermia (poikilothermic)
Neurogenic Shock-‐ Treatment
• Stop causa,ve factor if possible • Careful fluid resuscita,on • Vasopressors • Carefully warm pa,ent to normothermia • Treat any hypoxia as needed • Can treat bradycardia with Atropine
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Cardiogenic Shock
• Shock state due to ineffec,ve perfusion caused by inadequate contrac,lity of the myocardium.
Cardiogenic Shock-‐Causes
• Myocardial Infarc,on-‐ most frequent • Valvular disease • Dysrhythmias • Blunt cardiac trauma
Cardiogenic Shock-‐ Signs and Symptoms
• ↓ SV due to ↓ contrac,lity → ↓ CO even though the HR increases to try to compensate
• ↓ BP due to ↓ CO with a great increase in SVR to compensate for low CO
• Lungs fill with fluid-‐ crackles • May hear an S3 &/or S4 • Decreased UOP and skin is cool, pale and clammy • May have chest pain &/or dysrhythmias
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Cardiogenic Shock-‐ Treatment
• Treat underlying cause if possible • Administer oxygen • Treat low CO with + inotropes to ↑ contrac,lity
• Diure,cs and vasodilators to ↓ SVR • Treat dysrhythmias as needed • IABP if needed to ↑ coronary artery perfusion and ↓ aYerload
Obstruc,ve Shock
• Inability of blood to adequately fill all four chambers of the heart due to some type of obstruc,on to blood flow.
Common Causes of Obstruc,ve Shock
• Large Pulmonary Embolism • Cardiac Tamponade • Tension Pneumothorax
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Obstruc,ve Shock-‐ Signs and Symptoms
• ↓ SV due to inability of forward blood flow → ↓ CO even though the HR increases to try to
compensate • ↓ BP due to ↓ CO with a great increase in SVR to compensate for low CO. Narrowed pp with pulsus paradoxus noted
• JVD with clear lungs, lung sounds may be absent on one side if tension pneumothorax -‐tracheal devia,on
• Decreased UOP and skin is cool, pale and clammy
Treatment of Obstruc,ve Shock
• Cause directed: • Massive PE-‐ TPA, emergency open chest surgery
• Cardiac Tamponade-‐ Emergency pericardiocentesis
• Tension Pneumothorax-‐ Needle decompression of the affected side-‐ then chest tube inser,on
Case Study #1
• A 20 year old male arrives in your ED today with a GSW to the abdomen that occurred yesterday and has the following hemodynamic parameters:
HR-‐ 152 Temp-‐ 39.2
BP-‐ 76/44 MAP-‐ 55
Skin-‐ Pale, cool and dry with bounding pulses
RR-‐ 32 LOC-‐alert and agitated
SaO2-‐ 82% on RA Lungs-‐crackles bilaterally
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Is this pa,ent in Shock? If so, what kind?
What treatments would you an,cipate for him?
Treatments
• Broad spectrum an,bio,cs targe,ng specific e,ology aYer BC x2
• Fluid resuscita,on • Vasopressors aYer adequate fluid resuscita,on • Support oxygena,on …..intubate • Monitor lactate • Hang Norepinephrine drip to maintain MAP>65 • Surgical consult for abdominal wound
Case Study #2
• 45 yo female pa,ent arrives in your ED following a fall off the roof while fixing her swamp cooler with the following symptoms: LOC-‐ Obtunded Temp-‐ 35.7
HR-‐38 Skin-‐ warm and dry
BP-‐ 69/35 MAP-‐46
Moans to deep pain-‐ no movement
RR-‐ 6 and shallow SaO2-‐ 82% on 15L NRBM
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Is this pa,ent in Shock? If so, what kind?
What treatments would you an,cipate for her?
Treatments
• C-‐Spine immobiliza,on • Assist ven,la,on-‐intubate • Ac,vely warm pa,ent • Atropine to increase HR • BP control with vasopressors (Perhaps Dopamine to increase both HR and BP)
• CT of head and neck • Neurosurgery consult
Case Study #3
• 65 yo male pa,ent arrives in your ED with chest pain and SOB that has been increasing in severity for the past 2 days. He has the following symptoms:
LOC-‐ Alert and anxious Temp-‐ 36.7
HR-‐138 Skin-‐ cold and clammy
BP-‐ 82/67 MAP-‐56
Lungs have crackles to the scapula
RR-‐ 38 SaO2-‐ 82% on 15L NRBM
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Is this pa,ent in Shock? If so, what kind?
What treatments would you an,cipate for him?
12 lead ECG-‐within 10 minutes of arrival
Treatments
• MONA • Ac,vate CVL • Administer Beta Blocker if no contraindica,ons • Administer Heparin or LMWH • PTCA as indicated • Treat pulmonary edema with Lasix, NTG, CPAP or intuba,on if needed
• Posi,ve Inotrope aYer PTCA • ? IABP?
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Case Study #4
• A 15 yo male was thrown from his ATV and landed on his right side with the ATV landing on top of him. His hemodynamics are as follows:
HR – 165 Temp-‐36.5
BP-‐ 62/45 MAP -‐ 51
His menta,on varies btw. Lethargic and comba,ve
RR-‐38 and labored Skin is pale, cold and clammy
SaO2-‐74% on 15L NRBM JVD with diminished BS on leY
Is this pa,ent in Shock? If so, what kind?
What treatments would you an,cipate for him?
Treatments
• Needle decompression of leY lung – large whoosh of air heard.
• Start 2 large bore IV’s, draw trauma panel • Hang warmed isotonic crystalloid at rapid rate • Control any external bleeding • GCS and AVPU • Expose pt. while applying warming techniques • Give comfort measures
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Response To Treatments
HR 122 → 143 Skin remains cool, dry and very pale
RR-‐28 and shallow LOC-‐ lethargic, arouses briefly to painful s,muli
SaO2-‐ 89% on 15L NRBM JVD resolved → flat Lungs sounds equal
BP-‐ 80/62 aYer 2 L NS MAP-‐ 68
Temp-‐36.1
What Do You Think?
• Have we fixed this pa,ent? • Can you have more than one kind of shock at the same ,me?
• What other informa,on would you like to have on this pa,ent?
Case Study #4-‐ Con,nued
• Hb/Hct-‐ 5.1 & 15% • Abdomen is distended and taut with no BS • LeY leg is externally rotated with crepitus felt on palpa,on of the iliac crest
• FAST exam reveals a large amount of free fluid in the lower peritoneal area
• Your relief just called and they are going to be late!
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Addi,onal Treatments
• Administra,on of warmed, type-‐specific (if possible) PRBC’s
• Consider adding FFP and platelets aYer 4-‐5 units of PRBC’s given
• Calcium administra,on • Intubate pa,ent to secure airway • Emergency surgical consult • Call your relief and tell them to get their *#!*^% in here!
Ques,ons???? Thank you for your 6me and a7en6on
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