Systematic approach to a

patient with undifferentiated

Shock

By : Akhavan,R

Assistant professor of Emergency Medicine, MUMS

Introduction

Insufficient perfusion and oxygen delivery to the tissues.

High mortality!!

Rapid identification, assessment, and treatment is

critical!

Systematic approach with attention to time-sensitive

therapy.

Circulatory system

Three main components:

1. Cardiac function(the pump)

2. Intravascular volume(the tank)

3. Systemic vascular resistance(the pipes).

In shock, malfunction occurs with the

pump, tank, or pipes, such that

perfusion and oxygen delivery are

impaired.

Acute Pump dysfunction

Acute myocardial infarction

Acute valvular insufficiency

Arrhythmia

Mechanical obstruction :

1. Pericardial tamponade

2. Massive pulmonary embolism

Acute Tank malfunction

Hemorrhage

Hypovolemia

Tension pneumothorax

Pipe dysfunction

Sepsis

Anaphylaxis

Vascular catastrophes

1. Ruptured abdominal aortic aneurysm

2. Aortic dissection

Initial ED Assessment

Focused history and physical examination

ECG

Portable CXR

Laboratory studies:

Comprehensive metabolic panel

CBC(diff)

Coagulation profile

TPI

Type and screen

Beta HCG

Serum lactate concentration

Emergency Ultrasound

Pump Assessment

Ultrasound is critical in evaluating the pericardial space, the relative

size of the left and right ventricles, and overall left ventricular

function.

The ultrasound examination should be performed systematically to

decrease the probability of errors.

Parasternal long axis to assess left ventricular contractility

Apical four chamber to assess right ventricular contractility and size

in relation to the left ventricle

Subxiphoid view for pericardial space

Parasternal long axis view

Apical four chamber view

Subxiphoid view

Tamponade

Ph/ex:

o Palsus paradoxus

o Tachycardia

o Elevated JVP

o Beck triad

ECG findings:

o Tachycardia

o Low voltage QRS complexes

o Electrical alternans

CXR

Ultrasound : GOLD STANDARD

Massive PE

Ph/ex ( Tachycardia, tachypnea, hypoxemia,…)

ECG findings

Emergency Ultrasound:

Increase in the ratio of the right ventricle to the left ventricle

Hypokinesis of the right ventricle,

Paradoxic movement of the intraventricular septum toward the

left ventricle

Tricuspid valve regurgitation

Right ventricular strain

Primary cardiac failure

Cardiogenic Shock due to AMI(cool extremities,

JVD, Pulmonary Edema)

ECG findings

Lab data(TPI)

Ultrasound

Tank Assessment

Hypovolemia and hemorrhage, the most common causes of intravascular

volume depletion, are usually suggested by the history of present illness.

Physical examination findings associated with hemorrhagic shock include

tachycardia, tachypnea, mental status change, and hypotension.

Rectal examination

As in the assessment of pump dysfunction, ultrasound plays a central role in

the initial assessment of tank dysfunction.

Ultrasound measurements of the IVC

Small diameter of the inferior vena cava that changes significantly

with respirations suggests marked intravascular volume depletion.

A large diameter of the inferior vena cava that has minimal

variation with respirations may indicate adequate intravascular volume status or acute pump dysfunction (eg, tamponade, massive

PE).

Ultrasound for tank dysfunction

look for fluid in the abdominal and chest cavities, suggestive of a

traumatic intra-abdominal injury, ruptured ectopic pregnancy, or

hemothorax.

Look for Pnemothorax!!

Pipe Assessment

Anaphylaxis is a clinical diagnosis and should be

suspected when any of the following criteria are met:

1. Skin or mucosal involvement with acute onset of respiratory

distress or hypotension following exposure to a known antigen.

2. Any involvement of two or more organ systems (respiratory, skin

or mucosa, gastrointestinal, cardiovascular) following exposure

to a possible antigen.

3. Hypotension following exposure to a known antigen.

SEPSIS

Identifying the source of infection:

Pulmonary and genitourinary tracts

The abdomen,

Skin and soft tissue,

Indwelling catheters and devices.

Aortic dissection

Risk factors(hypertension, male gender, smoking,

advanced age, cocaine use and pregnancy ).

Hypertension, blood pressure differentials between

extremities, pulse deficits, and neurologic deficits.

Abnormality of the mediastinum in CXR.

Abdominal Aortic Aneurysm

For assessment of abdominal aortic catastrophes, ultrasound is an

important tool.

The presence of an abdominal aortic aneurysm in the setting of

undifferentiated shock should be considered a rupture until proven otherwise.

Initial ED steps

Airway and breathing

Large bore IV Lines

Fluid resuscitation

Continuous cardiac monitoring, pulse oximetry and VS

Acute monitoring of perfusion status( urine output, serum

lactate concentration trend, base deficit trend,…)

Specific treatment

Tank Dysfunction Special Treatment

Crystalloid or colloid??!!

Colloid solutions, such as hetastarch, are popular in

some regions of the world.

Recent studies on colloids, however, demonstrated an

increased incidence of acute kidney injury and failed to

demonstrate a decrease in the mortality rate.

As a result, crystalloid solutions remain the resuscitation

fluid of choice for patients with hypovolemic shock.

Crystalloid Solutions

Crystalloid solutions are commonly divided into saline

and balanced solutions.

Importantly, normal saline is not a true physiologic

solution and will reliably induce hyperchloremic

metabolic acidosis when given in large quantities.

Balanced solutions are more physiologic, including

lactated Ringer, Plasma-Lyte, Isolyte-E, and Hartmann

solution.

Administer a balanced solution to patients with severe or

worsening acidosis.

The total amount of fluid administered depends

on the type of shock and the patient’s response

to treatment.

In general, intravenous fluids should be

administered with targets of a mean arterial

blood pressure of at least 65 mm Hg and a urine

output greater than 0.5 mL/kg/h.

Additional Pharmacologic Therapies

TXA

Tranexamic acid (TXA) is an amino acid derivative that

binds plasminogen and prevents conversion to its active

fibrinolytic form.

Recent studies suggest that the early administration of

TXA to patients with severe traumatic hemorrhage

reduces the mortality rate.

PCC

Prothrombin complex concentrate (PCC) is a mixture of purified

vitamin-K-dependent clotting factors designed for use in patients

taking vitamin K antagonists (VKAs) (eg, warfarin) with significant bleeding.

PCC reverses VKA-induced coagulopathy efficiently and

significantly faster than fresh frozen plasma.

Its use is recommended for patients with VKA-associated major bleeding.

Similar effects have been noted in patients with non-VKA–induced

coagulopathy.

Recombinant activated factor VII

Early studies have not convincingly shown an

improvement in outcome with this therapy.

In addition, it is associated with a significant increase in

the rate of arterial thromboembolism.

Therefore, its use cannot be recommended at this time.

Questions?