Hypovolemic Shock — Study Notes (NCLEX Review) 💡 Definition ● Hypo = low | Vole = volume | Emic = blood → Low blood volume 📊 Stages (Classes) of Hypovolemic Shock Class I (Mild) % Loss <15% Blood Loss (mL) <750 mL HR <100, BP normal, skin pink/warm, UO >30 mL/hr, alert/anxious II 15–30% (Moderate) 750–1500 mL HR >100 (tachy), BP normal→slig htly low, RR ↑, UO 20–30 mL/hr, cool clammy skin, delayed cap refill, mild anxiety III (Severe) 30–40% 1500–2000 HR >120, mL hypotension, RR ↑ (resp failure), UO <30 mL/hr (oliguria), poor pulses, mottled skin, confused, acidotic IV (Critical) >40% >2000 mL ● Occurs when there’s decreased fluid volume in the intravascular system, leading to ↓ cardiac output → ↓ tissue perfusion → ↓ oxygen to cells → cell dysfunction. Occurs after ≥15% blood volume loss. Average blood volume = 5 L, so ≥750 mL loss can trigger symptoms. Key Findings ⚠️ Causes of Hypovolemic Shock 1. Absolute (External loss) ● Bleeding (trauma, surgery, GI bleed) ● Excessive fluid loss: vomiting, diarrhea, sweating, urination ● Disease processes: diabetes, endocrine disorders 2. Relative (Internal shift) ● Fluid moves inside the body but leaves the intravascular space → third spacing (burns, pancreatitis, fractures, internal bleeding) ● Massive vasodilation (septic shock) 🧠 Pathophysiology ↓ Intravascular volume → ↓ venous return → ↓ preload → ↓ stroke volume → ↓ cardiac output → ↓ oxygen to tissues → hypoxia → organ failure 🚨 General Signs & Symptoms ● Tachycardia Body compensates via the Sympathetic Nervous System (SNS): ● ↑ HR ● Vasoconstriction ● Blood shunted to vital organs (heart, brain) ● Hypotension ● Cool, clammy, pale skin ● Weak peripheral pulses ● Anxiety/confusion ● ↓ Urinary output (<30 mL/hr) HR >140, severe hypotension, RR ↑ (resp failure), anuria, coma, near death ● ↓ Central Venous Pressure (CVP) ● Albumin, Hetastarch ● ↓ PAWP (Pulmonary Artery Wedge Pressure) ● Large molecules stay intravascular longer 🩺 Nursing Interventions Goals: 1. Restore intravascular volume (fluids/blood) 2. Correct the underlying cause ● More expensive; possible anaphylaxis ● Monitor for fluid overload ● Warm fluids to prevent hypothermia (cold fluids impair clotting) 3. Blood & Blood Products ● PRBCs: restore volume + carry O₂ Key Actions: ● Monitor oxygenation: O₂, possible intubation ● Assess hemodynamics: BP, HR, mental status, urine output ● Insert urinary catheter: track UO (>30 mL/hr goal) ● Apply direct pressure if bleeding ● Position: Modified Trendelenburg (legs up 45°, head flat) ● IV Access: 2 large-bore (≥18G) for rapid fluid infusion ● Prepare for central line if severe ● Labs: CBC (Hgb/Hct), lactate, ABG, BUN/Cr, electrolytes 💧 Fluids for Resuscitation 1. Crystalloids (First-line) ● Normal Saline (NS) or Lactated Ringer’s (LR) ● Increase intravascular volume → ↑ preload & CO ● 3:1 Rule: 3 mL crystalloid per 1 mL blood loss ● Watch for fluid overload: crackles, JVD, edema ● Can diffuse through capillary walls (less volume stays intravascular) 2. Colloids ● Platelets: correct thrombocytopenia ● FFP: replace clotting factors ● Monitor for transfusion reactions 🧾 Key Lab Findings ● Hgb/Hct: ↓ if blood loss ● Lactate: ↑ (poor tissue perfusion) ● ABG: metabolic acidosis ● BUN/Cr: ↑ (renal hypoperfusion) ● CVP/PAWP: ↓ 🫀 Cardiogenic Shock – Study Notes (NCLEX Review) Definition ● Cardiogenic shock = heart fails to pump enough blood → ↓ cardiac output → ↓ tissue perfusion → ↓ oxygen to cells. ● Blood volume is NORMAL, but the heart’s pumping ability is impaired. ● Blood backs up → lungs (left side) and systemic veins (right side) become congested. 🧩 Basic Concept Term Cardiac Output (CO) Definition Amount of blood pumped per minute (normal: 4–8 L/min) Syst em Findings Hear t ↓ BP (<90 mmHg), weak pulses, chest pain, ↑ HR (tachycardia) Lung s Crackles, dyspnea, pulmonary edema, ↓ O₂, ↑ RR Formula CO = HR × Stroke Volume (SV) Brai n Confusion, restlessness, agitation Stroke Volume Blood pumped per beat (50–100 mL) Kidn eys ↓ UOP (<30 mL/hr), ↑ BUN/creatinine, oliguria Preload Stretch of ventricle at end of filling (diastole) Skin Cool, pale, clammy, slow cap refill Neck Vein s Jugular vein distention (↑ CVP) Afterload Resistance heart must pump against Contractility Strength of heart’s contraction Cardiac Index (CI) CO adjusted for body size (Normal: 2.5–4 L/min/m²; Shock: <2.2) 💡 When CO falls → ↓ tissue perfusion → ↓ oxygen → cell injury & organ failure ⚠️ Causes 🩸 Main cause: Acute Myocardial Infarction (MI) – death of heart muscle → ↓ contractility. Other causes: ● Dysrhythmias (e.g., ventricular tachycardia) ● Pericardial tamponade (heart can’t fill) ● Myocarditis or Endocarditis ● Valve/septal defects ● Pulmonary edema 🧠MI Patho Shortcut: → heart muscle weakens → ↓ pump → ↓ stroke volume → ↓ CO → ↓ perfusion → hypoxia → organ failure. 🩺 Signs and Symptoms Think “Heart can’t pump → Lungs fill, Organs starve.” 🧪 Hemodynamics ● ↓ Cardiac Index <2.2 L/min/m² ● ↑ PCWP/PAWP >18 mmHg ● ↑ CVP (backflow to right side) ● ↓ MAP <60 mmHg → poor perfusion 📊 Diagnostic Findings ● ↑ Troponin (heart muscle injury) ● ↑ BNP (ventricular stretch)B-Type Natriuretic Peptide ● ↑ Lactate >4 mmol/L (anaerobic metabolism) ● ↓ pH <7.35 (metabolic acidosis) ● CXR: Pulmonary edema ● Echocardiogram: ↓ ejection fraction 🎯 Nursing & Medical Management Goals 1. Improve perfusion to heart (reopen blocked arteries) 2. Increase cardiac output 3. Decrease workload of heart 4. Correct hypoxia and fluid overload 💊 Medications Class Examples Action Nursing Tips Vasopres sors Norepinep hrine, Dopamine ↑ BP & CO by vasoconst riction Monitor for arrhythmia s & tissue perfusion Inotropes Dobutami ne ↑ Contractilit y & CO Watch for ↓ BP (vasodilati on) Vasodilat ors Nitroglycer in, Nitroprussi de ↓ Afterload & preload → easier pumping Watch BP closely; may worsen hypotensi on Diuretics Furosemid e ↓ Pulmonary congestio n& preload Watch K⁺ (3.5–5 mEq/L), monitor urine output Fluids Use cautiously! Fluid overload risk Only small boluses if indicated 🩸 Procedures 1. Reperfusion Therapy ● PCI (stent) or CABG to restore blood flow post-MI. 2. Intra-Aortic Balloon Pump (IABP) ● Trend hemodynamic values (CO, CI, CVP, PCWP) Other Key Points ● Monitor for pulmonary edema (crackles, frothy sputum) ● Administer meds as ordered, titrate based on MAP >60 mmHg ● Prepare for emergency reperfusion procedures ● Provide calm environment, frequent reassessment ● Educate family and document responses 🧠 Anaphylactic Shock – NCLEX Review Definition Anaphylactic shock is a life-threatening allergic reaction that leads to massive vasodilation, airway obstruction, and decreased tissue perfusion. It’s a type of distributive shock, along with neurogenic and septic shock. ● Helps heart pump more effectively: ○ Inflates during diastole → ↑ coronary blood flow ○ Deflates during systole → ↓ afterload → easier ejection 🩹 Nursing Interventions (Simplified) A – Airway: Oxygen therapy, mechanical ventilation if needed. B – Breathing: Monitor RR, lung sounds, O₂ saturation. C – Circulation: ● Continuous cardiac monitoring ● Assess BP, HR, rhythm ● Monitor urine output (>30 mL/hr = good perfusion) ● Central line for fluids/meds 🔹 Pathophysiology When an allergen enters the body (via injection, ingestion, inhalation, or skin contact), it triggers mast cells and basophils to release histamine and other mediators throughout the body. → Causes vasodilation, increased capillary permeability, bronchoconstriction, and edema. → Result: Decreased circulating volume → decreased tissue perfusion → shock. ⚠️ Common Triggers ● Foods: shellfish, peanuts, eggs, milk ● Medications: antibiotics (especially penicillin), vaccines, contrast dye, NSAIDs ● Insect venom (bee, wasp) Skin reaction Itching, hives, redness ● Latex ● Exercise (rare) ● Idiopathic causes (unknown trigger) 🧬 Types of Reactions Systems affected: Cardiac, Respiratory, GI, and Skin 🩺 Signs and Symptoms System Manifestations Respiratory Dyspnea, wheezing, stridor, airway edema, hoarseness, coughing, nasal congestion Cardiac Tachycardia, hypotension, dizziness, syncope ● On first exposure, the body produces IgE antibodies that attach to mast cells/basophils. GI Nausea, vomiting, diarrhea, abdominal pain ● On second exposure, allergen binds to IgE → histamine release. Skin ● A Type I Hypersensitivity Reaction. Flushing, urticaria (hives), pruritus, angioedema 💡 Symptoms can begin within seconds to minutes of allergen exposure. 1. Anaphylactic Reaction (IgE-Mediated) ● Immune response → requires sensitization (previous exposure). 2. Anaphylactoid Reaction (Non-IgE Mediated) ● No sensitization needed; can occur with first exposure. ● Triggered directly by certain agents (e.g., contrast dye, NSAIDs, chemotherapy). ● Same reaction and symptoms as IgE-mediated type. 💥 Effects of Histamine Effect Clinical Result Vasodilation ↓ BP, ↓ tissue perfusion ↑ Capillary permeability Swelling, fluid shift → hypovolemia Bronchocons triction Wheezing, respiratory distress ↑ HR Compensatory tachycardia GI stimulation Nausea, vomiting, diarrhea ⚕️ Nursing Interventions & Medical Management 1. Prevention ● Assess and document allergies clearly. ● Use allergy wristbands and signage. ● Verify allergies before giving new meds or procedures. ● Be alert for first doses of antibiotics, contrast dyes, vaccines. 2. Emergency Actions (ACT FAST) Step Intervention A– Allergen & Airway Remove allergen if possible; maintain airway. Provide high-flow oxygen. Prepare for intubation if swelling/stridor present. C – Call for Help Activate Rapid Response or Code Team immediately. Start CPR if no pulse. T– Trendele nburg Position Supine with legs elevated (unless vomiting or airway obstruction) to improve venous return. F– First-Lin e Drug: Epineph rine Administer IM or SubQ; repeat as ordered if symptoms persist. Causes vasoconstriction (↑ BP), bronchodilation, and ↓ edema. May give IV epi for severe hypotension. A– Addition al Medicati ons - IV fluids (NS/LR) to support BP ● Bronchodilator (Albuterol) for wheezing ● Antihistamines: H1 (Diphenhydramine), H2 (Ranitidine or Famotidine) ● Corticosteroids (e.g., Methylprednisolone) to prevent recurrence | | S – Stay and Monitor | Continuous VS, cardiac rhythm, O₂ sat, urine output. Watch for biphasic reaction (recurrence within hours). | | T – Teach | Provide education before discharge. See below. | 💊 Key Drug: Epinephrine (EpiPen) ● Route: IM (preferred) or SubQ in middle of outer thigh ● Can inject through clothing if needed ● Hold for 3 seconds, then remove and massage site 10 seconds ● Effects: vasoconstriction, bronchodilation, ↑ BP, ↓ swelling ● Replace when expired ● Always seek medical care after use — biphasic reactions may occur 🧠 Patient Education ● Identify and avoid known allergens ● Carry an EpiPen at all times ● Wear a medical alert bracelet ● Teach family, caregivers, and teachers how to use EpiPen ● Follow-up with allergist for testing and management plan 🧠 Septic Shock – NCLEX Review Definition Septic shock is a form of distributive shock that occurs as a complication of sepsis when infection causes systemic vasodilation, capillary leak, and microclot formation, leading to decreased tissue perfusion and organ failure. ⚕️ What Is Sepsis? Sepsis = the body’s extreme, dysregulated response to infection. Instead of fighting infection locally, the immune system triggers widespread inflammation → damages blood vessels → impairs oxygen and nutrient delivery → organ dysfunction. Septic shock is the end stage of sepsis if not treated promptly. 📊 Diagnostic Criteria for Septic Shock The patient with sepsis is considered to be in septic shock if the following are present: Criteria Description Persistent Hypotension SBP < 90 mmHg despite fluid resuscitation Need for Vasopressors To maintain MAP ≥ 65 mmHg Serum Lactate > 2 mmol/L Indicates anaerobic metabolism and poor tissue perfusion 🩸 Pathophysiology Summary In septic shock, the heart can still pump adequately, but the vessels and capillaries are severely affected due to an exaggerated inflammatory response. Mechanisms 1. Vasodilation → ↓ systemic vascular resistance → ↓ BP 2. Capillary permeability ↑ → fluid leaks into tissues → ↓ circulating volume 3. Microclot formation (DIC) → blocks capillary flow → ↓ perfusion 4. Myocardial depression due to cytokines → ↓ cardiac function later 5. Hypoxia → anaerobic metabolism → ↑ lactic acid → acidosis 🧬 Key inflammatory mediators: cytokines (IL-1, TNF), platelet activating factor → cause vasodilation, leakage, clotting, and heart depression. 💀 Common Causes 🚨 Risk Factors: “SEPSIS” Letter Risk Factor S Suppressed immune system (AIDS, steroids, chemo, pregnancy) E Extreme ages (infants, elderly) P People with transplants S Surgical or invasive procedures I Indwelling devices (catheters, central lines, trachs) S Sickness: chronic diseases (DM, liver or kidney disease, alcoholism) 🩺 Stages and Clinical Manifestations Early (Warm) Phase – Compensated ● Warm, flushed skin (due to vasodilation) ● Tachycardia, bounding pulses ● BP may be normal or slightly low ● Fever (hyperthermia) ● Tachypnea (increased RR) ● Anxiety or restlessness ● Bacterial infections (most common): Gram-positive or Gram-negative ● ↑ cardiac output, ↓ systemic vascular resistance ● Viruses, fungi, parasites ● Urine output may begin to drop Most common infection sites: ● Respiratory (lungs – pneumonia) ● Genitourinary (UTI) ● Gastrointestinal (abdomen, peritonitis) ● Wounds or invasive devices (catheters, central lines) Late (Cold) Phase – Decompensated ● Cold, clammy, pale skin ● Severe hypotension ● Weak pulses, tachycardia ● Hypothermia ● ↓ cardiac output, ↑ SVR systemic vascular resistance (compensatory vasoconstriction) ● Oliguria (<30 mL/hr) or anuria ● Altered LOC → coma anti-inflammatory, antithrombotic. Watch for bleeding. ● Multiorgan failure 🧮 Key Labs Test Titrate vasopresso rs Norepinephrine (Levophed) first-line to maintain MAP ≥ 65 mmHg. If poor perfusion persists, add Dobutamine (inotrope). I IV fluids (Crystalloid s or Colloids) First treatment — large volume to fill dilated vessels. Warm fluids to avoid hypothermia. Target CVP: 8–12 mmHg and UOP >30 mL/hr. C Corticoster oids (low dose) Used in some patients unresponsive to fluids and vasopressors to reduce inflammation. S Strict hemodynam ic monitoring Use arterial/central lines to monitor MAP, CVP, PAWP, and response to therapy. H High-flow oxygen or intubation Keep O₂ sat > 95%; treat ARDS if present. O Obtain cultures Blood, urine, sputum, wound — before antibiotics. C Control blood glucose Keep <180 mg/dL; insulin drip if needed. Hyperglycemia impairs immunity. K Keep checking lactate levels Guides perfusion status; persistently high = poor tissue oxygenation. Expected Result Serum lactate > 2 mmol/L (tissue hypoxia) WBC Elevated or ↓ (late sepsis) Procalcit onin Elevated (infection marker) Blood cultures Positive for microorganism Platelets, May show DIC (decreased PT, aPTT, platelets, prolonged times) Fibrinoge n ABG T Metabolic acidosis (↑ lactate, ↓ pH) ⚕️ Nursing Interventions and Treatment Goals 🎯 Main Goal: Restore tissue perfusion and oxygenation, treat infection, prevent organ failure. “SEPTIC SHOCK” Mnemonic Letter Intervention Key Points S Start antibiotics early Obtain cultures first, but don’t delay antibiotics. Broad-spectrum initially, then narrow once organism identified. E Enteral nutrition early Preserves gut integrity and helps healing. Prevent stress ulcers (may use H2 blockers like Famotidine). P Protein activated C (Drotrecogi n Alpha) Discontinued drug, but remember mechanism: 🩺 Additional Nursing Considerations ● Insert Foley catheter for strict intake/output (monitor renal perfusion). ● Prevent DIC bleeding: monitor for oozing, petechiae, or bruising. ● The parasympathetic system (PSNS) becomes unopposed → bradycardia ● Loss of vasomotor tone → massive vasodilation ● Decreased systemic vascular resistance (SVR) → hypotension ● Prevent pressure injuries (poor perfusion = high risk). ● Blood pooling in extremities → decreased venous return and cardiac output ● Provide psychological support to patient/family. ● Impaired temperature regulation → hypothermia ● Expect ICU care for advanced management (mechanical ventilation, vasopressors, dialysis). Neurogenic Shock NCLEX Review So, cardiac output and tissue perfusion both drop, leading to classic shock symptoms. Key Characteristics Definition Parameter Neurogenic shock is a type of distributive shock that results from the loss of sympathetic nervous system (SNS) function, leading to massive vasodilation, bradycardia, and hypotension. It causes decreased tissue perfusion because blood is not effectively distributed to vital organs. Heart Rate Bradycardia (due to unopposed PSNS) Blood Pressure Hypotension (from vasodilation and pooling) Temperatu re Hypothermia, poikilothermic (body takes on environmental temp) Skin Warm and dry extremities, but cold core ● Spinal cord injury above T6 (most common) Preload/Aft erload Decreased due to pooling and dilation ● Spinal anesthesia Cardiac Output Decreased Causes Neurogenic Shock ● Drugs affecting the SNS (e.g., barbiturates, opioids) ● Brain or spinal cord damage Pathophysiology Neurogenic Shock vs Spinal Shock Feature Neurogeni c Shock Spinal Shock Focus Hemodyna mic problem (BP, HR) Neurologic problem (reflexes, movement, sensation) Bradycar dia & Hypoten sion Present May or may not be present The sympathetic nervous system controls: ● Heart rate ● Blood vessel tone (vasoconstriction and dilation) ● Blood pressure When the SNS is disrupted: Reflexes Intact below injury (at first) Absent below injury (temporary) Signs and Symptoms ● Hypotension (massive vasodilation) ● Bradycardia ● Warm, dry skin ● Poikilothermia (can’t regulate body temp) ● Hypothermia ● Decreased cardiac output ● Decreased tissue perfusion ● Venous pooling → DVT risk Nursing Interventions & Treatment Goal: Maintain airway, breathing, circulation, and spinal stability while restoring perfusion and temperature regulation. 1. Airway and Breathing ○ Assess for respiratory failure (especially with cervical injuries). ○ Prepare for intubation and mechanical ventilation if needed. 2. Circulation ○ Maintain MAP 85–90 mmHg to ensure spinal and organ perfusion. (Dave & Cho, 2018) 3. Fluids: ○ Crystalloids (NS, LR) to fill dilated vessels and improve venous return. 4. Vasopressors: ○ Used if fluids don’t improve BP. ○ Dopamine or Norepinephrine: increases SVR and BP. ○ Dopamine also increases HR (positive inotrope). 5. Bradycardia: ○ Atropine (blocks PSNS stimulation) ○ Temporary pacemaker if severe. 6. Temperature Regulation ○ Warm environment and rewarming devices. ○ Rewarm slowly; monitor core temp to prevent complications. 7. Spinal Protection ○ Immobilize the spine (cervical collar, backboard, logrolling). ○ Prevent further spinal cord damage. 8. Urinary Output Monitoring ○ Foley catheter for accurate I&O. ○ Aim for >30 mL/hr, indicates adequate renal perfusion. 9. Prevent DVT ○ Compression stockings, ROM exercises, and anticoagulants as ordered. ○ Avoid crossing legs or placing pillows under knees. 10.Monitor for Complications ○ Hypoxia ○ Use with caution — these patients usually have normal blood volume. ○ Worsening hypotension ○ Monitor for fluid overload (crackles, dyspnea, ↑ CVP). ○ Decreased urine output ○ Cardiac dysrhythmias ○ Core hypothermia Obstructive Shock (OS) Definition Obstructive shock occurs when there is a mechanical obstruction in the heart or great vessels that impedes venous return or blocks effective cardiac pumping. ● O – Oxygen therapy ● X – Fluid replacement: ○ Crystalloids: Isotonic or hypotonic solutions ○ Colloids: Plasma expanders ○ Blood and blood products Manifestations ● Jugular vein distention (JVD): Bulging of neck veins due to impaired venous return; common in heart failure and circulatory obstruction. ● Pulsus paradoxus: Exaggerated drop in systolic BP during inspiration, seen in cardiac tamponade or constrictive pericarditis. ● F – Emergency care measures Medications ● Adrenergics ○ Vasoconstrictors: Adrenaline, Noradrenaline, Aramine ○ Inotropes: Dopamine, Dobutamine, Isoprenaline ● Vasodilators: Nitroglycerin, Nitroprusside Diagnostic Studies 1. History and physical examination ● Diuretics ● Sodium bicarbonate 2. Laboratory tests 3. 12-lead ECG 4. Continuous ECG monitoring 5. Chest X-ray, MRI, or CT scan 6. Continuous pulse oximetry 7. Invasive and non-invasive hemodynamic monitoring Interprofessional Care (Focus: COP) ● C – Cause: Treat the underlying cause ● O – Oxygenation: Increase arterial oxygenation Nursing Assessment (ABC’s + T) ● A – Airway ● B – Breathing ● C – Circulation ● T – Tissue perfusion Nursing Diagnoses ● Decreased cardiac output ● Ineffective tissue perfusion ● Anxiety ● P – Perfusion: Improve tissue perfusion Nursing Interventions Interventions (MOXFEM) ● M – Medications Decreased Cardiac Output ● Assess and monitor cardiac function ● Measure and record intake and output ● Monitor bowel sounds ● Maintain bed rest and a calm environment Ineffective Tissue Perfusion ● Monitor skin color, temperature, turgor, and moisture ● Assess level of consciousness ● Monitor body temperature Anxiety ● Identify and address the cause of anxiety ● Administer prescribed pain medications ● Enhance comfort and reduce restlessness ● Provide emotional support
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