Nursing Care for the Patient in Shock

Vocabulary flashcards covering key terms, hemodynamics, stages, types, monitoring, and treatments related to shock management.

Shock

A clinical syndrome of decreased tissue perfusion and impaired cellular metabolism caused by problems with the pump, volume, or vessels.

Cardiogenic Shock

Type of shock resulting from pump failure (systolic or diastolic dysfunction) leading to reduced cardiac output.

Hypovolemic Shock

Shock caused by decreased intravascular volume from absolute (hemorrhage, GI loss) or relative (third-spacing) fluid loss.

Distributive Shock

Shock due to misdistribution of circulating blood volume; includes neurogenic, anaphylactic, and septic shock.

Obstructive Shock

Shock produced by a physical blockage to blood flow that decreases cardiac output (e.g., tamponade, PE).

Neurogenic Shock

Distributive shock from loss of sympathetic tone after spinal injury (T6 or above), anesthesia, or drugs, causing massive vasodilation.

Anaphylactic Shock

Distributive shock triggered by hypersensitivity reaction causing vasodilation, capillary permeability, and bronchospasm.

Septic Shock

Distributive shock from overwhelming infection with hypotension despite fluids and evidence of inadequate tissue perfusion.

Cardiac Output (CO)

Amount of blood ejected by the heart in one minute; normal 4–8 L/min.

Stroke Volume (SV)

Amount of blood ejected with each heartbeat; normal 60–150 mL/beat.

Preload

Ventricular end-diastolic volume/pressure; estimated by CVP or PAWP and influenced by venous return.

Afterload

Resistance the ventricles must overcome to eject blood; assessed by SVR or PVR.

Contractility

Intrinsic ability of cardiac muscle to contract independent of preload and afterload; assessed clinically by CO and echocardiogram.

Central Venous Pressure (CVP)

Pressure in the right atrium or vena cava reflecting right-sided preload; normal 2–8 mm Hg.

Pulmonary Artery Wedge Pressure (PAWP)

Balloon-occluded pressure reflecting left-sided preload; normal 6–12 mm Hg.

Systemic Vascular Resistance (SVR)

Afterload against the left ventricle; normal 800–1200 dyn·s/cm⁵.

Pulmonary Vascular Resistance (PVR)

Afterload against the right ventricle; normal <250 dyn·s/cm⁵.

Mean Arterial Pressure (MAP)

Average arterial pressure during a cardiac cycle; ≥65 mm Hg needed for organ perfusion.

Pulse Pressure

Difference between systolic and diastolic BP; normal ≈40 mm Hg (low = vasoconstriction, high = vasodilation).

Systemic Inflammatory Response Syndrome (SIRS)

Generalized inflammatory state resembling sepsis without an identifiable infection.

Multiple Organ Dysfunction Syndrome (MODS)

Failure of two or more organ systems so that homeostasis cannot be maintained without intervention.

Compensatory Stage of Shock

Early stage where neural, hormonal, and biochemical mechanisms maintain perfusion despite decreased CO.

Progressive Stage of Shock

Stage where compensatory mechanisms fail, leading to profound hypotension, tachycardia, and organ dysfunction.

Refractory (Irreversible) Stage

Final stage of shock with severe hypotension, hypoxia, and multiple organ failure unresponsive to therapy.

Anasarca

Diffuse, profound edema resulting from increased capillary permeability during progressive shock.

Disseminated Intravascular Coagulation (DIC)

Consumptive coagulopathy causing microthrombi and bleeding; risk increases in progressive shock.

Acute Tubular Necrosis (ATN)

Ischemic injury to renal tubules leading to acute kidney failure during shock.

Acute Respiratory Distress Syndrome (ARDS)

Severe respiratory failure from inflammatory lung injury often seen in progressive shock.

Mixed Venous Oxygen Saturation (SvO₂)

Oxygen saturation of blood in the pulmonary artery; normal 60–80 %, reflects balance of O₂ delivery and consumption.

Central Venous Oxygen Saturation (ScvO₂)

Oxygen saturation of blood in the superior vena cava; normal 70–80 %, used as surrogate for SvO₂.

qSOFA Score

Quick bedside tool for sepsis risk: hypotension (SBP ≤100), altered mental status, tachypnea (RR ≥22); ≥2 = higher risk.

Sympathomimetic Drugs

Medications (norepinephrine, dopamine, phenylephrine, vasopressin) that cause peripheral vasoconstriction to raise BP.

Vasodilators

Drugs (nitroglycerin, nitroprusside) that decrease afterload; useful in cardiogenic shock to improve CO.

Positive Inotropes

Agents (dobutamine, epinephrine, milrinone) that increase myocardial contractility.

Negative Inotropes

Medications (beta-blockers, calcium channel blockers) that decrease contractility and heart rate.

Fluid Resuscitation

Administration of crystalloids or colloids to restore intravascular volume; first-line in hypovolemic, septic, anaphylactic shock.

3:1 Rule

Guideline to give 3 mL of crystalloid for every 1 mL of estimated blood loss in hypovolemic shock.

Intra-Aortic Balloon Pump (IABP)

Mechanical device that inflates in diastole to improve coronary perfusion and deflates in systole to reduce afterload.

Left Ventricular Assist Device (LVAD)

Mechanical pump that supports or replaces the function of a failing left ventricle.

Anaphylaxis First-Line Drug

Intramuscular epinephrine: produces vasoconstriction and bronchodilation, opposing histamine effects.

Phenylephrine

Pure alpha-agonist vasopressor commonly used in neurogenic shock to increase SVR.

Atropine

Anticholinergic drug used to treat bradycardia in neurogenic shock.

Norepinephrine (Levophed)

First-choice vasopressor for septic shock after adequate fluid resuscitation; increases SVR and MAP.

Crystalloids

Isotonic or hypertonic electrolyte solutions (e.g., normal saline) used for rapid fluid replacement.

Colloids

High-oncotic solutions containing large molecules (e.g., albumin) that stay in the intravascular space to expand volume.

Pulmonary Artery Catheter

Flow-directed catheter used to measure PA pressures, PAWP, and SvO₂ for hemodynamic monitoring.

Arterial Line

Invasive catheter placed in an artery to provide continuous blood pressure monitoring and blood sampling.

Hemoglobin Threshold for Transfusion

Generally transfuse packed RBCs when hemoglobin <7–8 g/dL in shock patients.

MAP Goal in Shock

Maintain mean arterial pressure at or above 65 mm Hg to ensure organ perfusion.

Pulse Pressure <40 mm Hg

Indicates vasoconstriction and reduced stroke volume, often seen early in shock.

Pulse Pressure >40 mm Hg

Suggests vasodilation, possible in distributive shock states.

Relative Hypovolemia

Condition where fluid moves out of the vascular space (third spacing) creating a low effective circulating volume.

Absolute Hypovolemia

True loss of circulating fluid volume through hemorrhage, vomiting, diarrhea, diuresis, or DI.

Angiotensin II Role

Hormone released during compensatory stage causing vasoconstriction and renal Na⁺/water reabsorption.

Ventilation-Perfusion Mismatch

Imbalance between air flow and blood flow in lungs; contributes to hypoxemia in shock.

Anxiety & Confusion in Shock

Early neurologic signs of decreased cerebral perfusion, especially in cardiogenic and hypovolemic shock.

Anuria

Almost complete absence of urine output (<50 mL/day); late renal manifestation of severe shock.

Thrombolytic Therapy

Use of drugs (e.g., tPA) to dissolve clots causing obstructive shock from pulmonary embolism.

Decompressive Laparotomy

Surgical procedure to relieve abdominal compartment syndrome in obstructive shock.

Sodium Bicarbonate

Medication sometimes used to correct severe metabolic acidosis during refractory shock.

High-Flow Oxygen

Initial therapy in all shock states to maximize arterial oxygen saturation.

Enteral Nutrition in Shock

High-protein, high-calorie feeding started within 24 hours to support metabolism and gut integrity.

Insulin Drip Goal

Maintain blood glucose <180 mg/dL in critically ill shock patients to reduce complications.

Dopamine (Intropin)

Dose-dependent catecholamine providing inotropy and vasoconstriction; alternative vasopressor.

Vasopressin (Pitressin)

Non-adrenergic vasoconstrictor used adjunctively in septic shock refractory to catecholamines.

Nitroprusside (Nipride)

Potent arterial and venous vasodilator employed to decrease afterload in cardiogenic shock.

Dobutamine

Beta-agonist positive inotrope that increases contractility and stroke volume with minimal vasoconstriction.