Shock Diagnosis and Management Overview

Shock Diagnosis and Management

• Empirical Criteria for Shock: Includes III appearance, altered mental status, heart rate >100 beats/min, respiratory rate >20 breaths/min, PaCO2 <32 mmHg, arterial base deficit <-4 mEq/L, lactate >4 mM/L, urine output <0.5 mL/kg/h, and arterial hypotension lasting >30 minutes.

Importance of Rapid Recognition

• Rapid shock recognition is critical for timely assessment and treatment before the condition worsens, even before the exact cause is known.

Physiological Signs of Shock

• Worsening base deficit, lactic acidosis, stressed appearance (pale, asthenic, sweating, tachypneic), weak and rapid pulse.

Blood Pressure Reliability

• Blood pressure readings may be unreliable in severe hypotension, as compensatory adrenergic reflexes might keep blood pressure normal initially.

Perfusion Monitoring Methods

• Urine output evaluation, mental status assessment, liver/coagulation tests, lactate concentration, and base deficit assessment are also used to monitor perfusion besides vital signs.

Lactate Concentration Significance

• A lactate concentration greater than 4.0 mM/L in a patient with suspected shock indicates severe circulatory insufficiency, predicting potential multiple organ failure and patient outcomes.

Hemorrhagic Shock Treatment

• Ensure ventilation, control hemorrhage, initiate isotonic crystalloid infusion, and start PRBC infusion if needed.

Septic Shock Differentiation

• Septic shock is defined as sepsis with hypotension requiring vasopressors after fluid loading, and lactate >2 mmol/L.

Cardiogenic Shock Management

• Focus on alleviating increased work of breathing, providing oxygen with PEEP, initiating vasopressors/inotropes, and reversing the underlying cause.

Quantitative Resuscitation

• Resuscitation aims to restore vital organ function within the first 6 hours by targeting predefined physiological endpoints to ensure adequate systemic perfusion.

Alternative Fluid Administration

• Intraosseous (IO) access is used for temporary fluid administration if oral or IV access is not feasible in shock patients.

Lactate Clearance in Resuscitation

• Monitoring lactate clearance (aiming 10-20% reduction) aids in evaluating effectiveness of shock resuscitation efforts.

PRBC Infusion Initiation

• Initiate PRBC infusion when evidence indicates poor organ perfusion and/or when massive hemorrhage is imminent.

Septic Shock Management

• Measures include ensuring adequate oxygenation, administering crystalloids, initiating antibiotics, considering surgical drainage and/or starting vasopressors if necessary.

Additional Measures for Poor Lactate Clearance

• Further steps to address systemic perfusion, such as adjusting fluid therapy or vasopressor support, may be in order if initial treatment fails to improve lactate clearance.

Key Empirical Criteria for Shock

• III appearance, altered mental status, heart rate >100, respiratory rate >20, PaCO2 <32, base deficit <-4, lactate >4, urine output<0.5, and arterial hypotension >30 minutes.

BP and HR Reliability

• Low perfusion could falsely show normal BP and HR.

Global Perfusion Assessment Markers

• Arterial and venous lactate, and/or base deficit are reliable perfusion markers in shock.

Physical Exam for Cardiac Tamponade

• Muffled heart sounds with jugular venous distension often signal cardiac tamponade

Lab and Imaging Studies for Shock

• Chest X-ray, ECG, complete blood count (CBC), urinalysis, electrolytes, kidney/liver function tests, ABG (to assess base deficit and lactate levels), and bedside ultrasound.

Sepsis Definition (Sepsis-3 criteria)

• Sepsis (suspected infection/SOFA score increase ≥2) and hypotension requiring vasopressors after fluid resuscitation, and lactate >2 mmol/L.

Hemorrhagic Shock Interventions

• Immediate control of hemorrhage (direct pressure, REBOA), appropriate crystalloid usage (10-20ml/kg), and appropriate PRBC transfusion in case of poor perfusion and massive hemorrhage.

Indicators of Organ Hypoperfusion

• Hypotension, tachycardia, low cardiac output, dusky/mottled skin, slow capillary refill, altered mental status, low urine output, and/or low central venous oxygen saturation and increased lactate levels.

CMS Shock Differentiation

• Unlike CMS 2001 criteria, Sepsis-3 does not rely on SIRS and uses SOFA score instead.

Hemorrhagic Shock Fluid Management

• Rapid control of the bleed, judiciously administered crystalloid (10 to 20 mL/kg) then PRBC if needed.

Prehospital Hypotension and Prognosis

• In hospital mortality rates associated with prehospital hypotension are considerably higher compared to those without it, regardless of the cause.

Adequate Lactate Clearance during Resuscitation

• Achieving a 10–20% decrease in lactate within 2 hours of initiating treatment is a sign of adequate resuscitation; failure to achieve this typically necessitates further interventions.

Use of Arterial Lines in Shock Patients

• In shock patients, especially those receiving vasoactive treatments, arterial lines are often used to track BP changes effectively, while also allowing assessment of dynamic variables.

Peripheral IV for Vasoactive agents

• When central/ IO access isn't available, large-gauge peripheral IV catheter in antecubital fossa or similar site should be considered for vasoactive/inotrope use.