Cardiogenic Shock With Normal Blood Pressure

Why Early Cardiogenic Shock Is Often Missed

Cardiogenic shock is a life-threatening condition that is frequently recognized too late. One key reason is that patients do not always appear as we expect a patient in shock to appear. Blood pressure may be normal, vital signs only mildly abnormal — and the NEWS score surprisingly low.

This article explains why this makes cardiogenic shock particularly dangerous, and which clinical signs should outweigh numbers alone.

Key Learning Points

• Cardiogenic shock can occur with normal blood pressure

• A low NEWS score does not exclude severe circulatory failure

• Early symptoms are often non-specific, such as functional decline and fatigue

• Clinical signs of poor perfusion are crucial

• Vital signs must always be interpreted in the context of clinical assessment and physiology

  
  

These points are clearly illustrated in the case below.

Case Presentation: Functional Decline as the First Sign of Shock

A woman is admitted via emergency medical services due to acute functional decline and reduced general condition over a two-week period. She reports increasing fatigue, poor oral intake, and progressive dyspnea. No fever. No chest pain.

On admission:

• Awake and responsive

• Afebrile

• SpO₂ 96% on room air

• Blood pressure 123/93 mmHg

• Respiratory rate ~25/min

  
  

She is triaged with a NEWS score of 4, classified as low–moderate risk.

NEWS Score

At the same time, she is described as:

• Cold and clammy peripherally

• Profoundly weak

• Mentally slowed

• Markedly worse over the last 24 hours according to relatives

  
  

Shortly after admission, she develops severe circulatory collapse, with blood pressure dropping to 55/41 mmHg despite ongoing fluid resuscitation.Serum lactate is 11 mmol/L.

ECG on admission

Sinus rhythm, heart rate ~100 bpm.

Acute echocardiography reveals:

• Severely reduced left ventricular systolic function (EF 10–15%)

• Dilated left ventricle

• Apical thrombus

  
  

The diagnosis of cardiogenic shock is established.

What Is Cardiogenic Shock?

Cardiogenic shock occurs when the heart is unable to pump sufficient blood to meet the metabolic demands of the body. The result is inadequate organ perfusion, tissue hypoxia, and eventually multiorgan failure.

Unlike other shock states, the primary problem in cardiogenic shock is:

• Low cardiac output (low-flow state)

  - not necessarily:

• Hypotension, particularly in the early phase

  
  

This is a key concept for understanding why cardiogenic shock is so often overlooked.

Why Cardiogenic Shock Does Not Always Look Dramatic

Shock is often associated with:

• Profound hypotension

• Marked tachycardia

• Severe respiratory distress

Early cardiogenic shock frequently does not fit this pattern.

Patients may present with:

• Near-normal blood pressure

• Only moderate tachycardia

• Normal oxygen saturation

  
  

Despite this, perfusion to vital organs may already be critically impaired.

The problem is not the pressure - but the cardiac output.

What Is the NEWS Score - and Why Can It Mislead Us?

The National Early Warning Score (NEWS) is a standardized tool used to identify patients at risk of clinical deterioration. It is based on vital signs including respiratory rate, oxygen saturation, blood pressure, heart rate, temperature, and level of consciousness.

NEWS functions as a track-and-trigger system and correlates well with risk of:

• Acute deterioration

• ICU admission

• Short-term mortality (especially within 24–48 hours)

  
  

It is therefore highly useful for triage and monitoring.

Limitations of NEWS in Cardiogenic Shock

NEWS performs well in detecting:

• Respiratory failure

• Sepsis

• General physiological stress

  
  

However, it performs poorly in detecting:

• Low cardiac output states

• Peripheral hypoperfusion

• Early cardiogenic shock

  
  

A patient may therefore have a low or moderate NEWS score, while organ perfusion is severely compromised.

This is a critical limitation that must be acknowledged in clinical practice.

Normal Blood Pressure Does Not Equal Adequate Circulation

A fundamental principle in cardiogenic shock is:

Normal blood pressure ≠ adequate organ perfusion

The body may temporarily compensate through:

• Increased systemic vascular resistance

• Vasoconstriction

  
  

This can preserve blood pressure - at the cost of:

• Peripheral circulation

• Renal perfusion

• Cognitive function

  
  

In this case, the patient had normal blood pressure on arrival, despite already progressing toward life-threatening low-flow shock.

Clinical Red Flags That Should Never Be Ignored

When cardiogenic shock is suspected, the following findings should raise alarm - regardless of NEWS score:

• Cold, clammy skin

• Narrow pulse pressure

• Oliguria

• Altered mental status

• Disproportionate fatigue or weakness

• Elevated lactate without clear infection

• Poor or negative response to fluid resuscitation

  
  

It is often the sum of subtle clinical signs, combined with early echocardiography, that reveals the true severity.

What Does This Case Teach Us?

This patient clearly illustrates that:

• Cardiogenic shock may present with non-specific symptoms, such as functional decline

• NEWS scores can provide false reassurance

• Clinical judgment is essential for early recognition

  
  

Cardiogenic shock carries a 30-day mortality of approximately 40%. Early identification and prompt initiation of appropriate therapy are therefore critical.

What Comes Next?

Part 2 will cover in detail:

• Cardiac output

• Blood pressure

• Systemic vascular resistance

• Physiology of the cardiogenic shock

  
  

Part 3 will focus on:

• Central venous pressure (CVP)

• Central venous oxygen saturation (SvO₂)

• Lactate

• How these parameters are used in practice - and when they mislead

  .

FAQ - Cardiogenic Shock

1) What is cardiogenic shock?

Cardiogenic shock is a life-threatening condition in which the heart fails to pump enough blood to ensure adequate organ perfusion. The primary problem is usually low cardiac output (low-flow shock), leading to tissue hypoxia and organ failure.

2) Can cardiogenic shock occur with normal blood pressure?

Yes. In early stages, compensatory vasoconstriction and increased systemic vascular resistance may maintain blood pressure. Clinical signs - such as cold extremities, altered mental status, and low urine output — are therefore more important than blood pressure alone.

3) Can the NEWS score be low in cardiogenic shock?

Yes. NEWS is most sensitive for respiratory failure and sepsis, but less sensitive for low-flow states. A patient may be critically ill with a low or moderate NEWS score if perfusion is impaired without major abnormalities in vital signs.

4) What symptoms can cardiogenic shock cause?

Early symptoms are often non-specific:

• Severe fatigue or functional decline

• Progressive dyspnea

• Reduced appetite

• Dizziness or altered mental status

• Cold, clammy skin

  
  

5) What are the key clinical signs of cardiogenic shock?

Typical red flags include:

• Cold, clammy periphery

• Narrow pulse pressure

• Oliguria

• Altered mental status

• Elevated lactate without clear cause

• Poor response to fluid therapy

  
  

6) Why can cardiogenic shock be mistaken for sepsis or hypovolemia?

Because patients may present with tachypnea, fatigue, and elevated lactate - features also seen in sepsis. Hypotension may be misinterpreted as volume depletion. In cardiogenic shock, signs of low flow and congestion are often present, and patients may deteriorate with uncritical fluid administration.

7) When should cardiogenic shock be suspected in the emergency department?

When a patient appears disproportionately unwell compared to their NEWS score or “acceptable” vital signs - especially with cold periphery, narrow pulse pressure, low urine output, and altered mental status.

8) Which investigations are most useful early?

Early assessment should include:

• Careful clinical examination focused on perfusion

• ECG

• Blood gas analysis with lactate

• Early bedside ultrasound / echocardiography when suspected