systematic approach to a patient with undifferentiated...
TRANSCRIPT
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?