Undifferentiated shock

Definition

1. SBP <90 in nl pt
2. SBP<100 with h/o HTN or age >60
3. ABG = lactate > 4 or base def < -4
4. MAP = SVR x CO

Types

Type	Skin	HR	Oth
Hypovolemic	cold	inc
Obstructive	cold	inc
Cardiogenic	cold	inc/dec	?dysth
Distributive	warm	inc
Neurogenic	warm	dec

Undifferentiated Hypotension Algorithm

Check:

1. HR (age appropriate)
   1. <40 and >150-180 --> likely HR = Primary etiology
      1. Tx with cardioversion/defib or pace
   2. Plasma vs. RBC loss
      1. Evaluate CVP, IVC, UOP
      2. Check for GI, intraperitoneal, lung, retroperitoneal loss/sequestration
2. Contractility
   1. Bounding/thready pulse, hyperdynamic precordium
   2. Dx with ultrasound
      1. Will have high afterload
         1. May be due to STEMI, CHF
3. Forward flow
   1. Valvular dysfunction (MR) or obstruction
      1. Evaluate via auscultation, ultrasound
         1. Consider PE, HOCM
4. Volume Status - LVEDP (approx by CVP, IVC, etc.)
   1. History of volume loss
   2. Lung Exam
   3. Mucous membrane
   4. Ultrasound IVC (RUQ window or AAA)
   5. Hemeacuu, Guaic
   6. Cardiac Ultrasound
5. SVR
   1. Pathologic vasodilation
      1. Warm extremities, bounding pulse
         1. Consider sympathetic dysregulation/neurogenic shock
   2. Cool extremities and "normal" BP
      1. Consider vasoconstriction and treat as hypotension from the top

Lack of Response to Normal Tx (DDX)

1. Cardiogenic
   1. Acute Valvular Regurg/VSD
   2. CHF
   3. Dysrhythmia
   4. Ischemia/Infarction
   5. Myocardial Contusion/Myocarditis
2. Obstructive
   1. Air embolism
   2. Aortic Stenosis
   3. Cardiac Tamponade
   4. Massive PE
   5. Tension Pneumo
3. Distributive
   1. Adrenal Crisis
   2. Anaphylaxis
   3. Neurogenic
   4. Sepsis
   5. Toxicologic
4. Hypovolemic
   1. Hemorrhage Traumatic and Non-traumatic
   2. Severe Dehydration

See Also

• Ultrasound in Shock and Hypotension
• Cardiogenic Shock

Source

2/06 DONALDSON (Adapted from Tintinalli)

Morchi 2010