Big Shock…..Do we ❤ POCUS?

Although the evidence for POCUS in shocked patients doesn’t show a survival benefit it does support the view that it is a useful adjunct for clinicians in diagnosing and treating patients.

  An approach to undifferentiated hypotension

If there is an obvious cause of the hypotension, such as trauma or a GI bleed, you don’t need this approach. Just start treatment as usual. Control the airway and supply oxygen. Most times this will be with basic airways maneuvers or an LMA. You can always intubate later when you have the patient better resuscitated.

  Approach to the Critically Ill Child: Shock

To understand how kids with shock present differently than adults, it’s important to discuss a few basic differences regarding intravascular volume and cardiovascular system in children especially neonates and infants (1-24 months of age). Also remember shock is defined the exact same way as it would be in adults even though the presentation and underlying physiology may differ. Shock is simply a state where tissue/organ blood flow is inadequate to meet tissue/organ metabolic demands.

  Resus of the hypotensive patient Part 1 - When IV Fluids Kill

There is probably no other drug emergency providers administer more often than IV fluids. We give them to patients with mild heat exhaustion, gastroenteritis and orthostatic dizziness to name a few. These patients tend to feel better, go home and no harm comes to them. However, for the subset of patients with shock and potential recipients of large volume resuscitation, excessive IV fluids can harm.

 Approach to shock

Shock is a state of systemic hypoperfusion, with inadequate blood supply to the tissues. Unfortunately, this may occur in different ways. The most simple physiology of shock is cardiogenic shock, with low cardiac output to the entire body. However, septic shock can occur with an elevated cardiac output due to microvascular dysfunction at the tissue level (blood shunts through some vessels, while ignoring others). Because shock has varying physiologies, it defies any simple operational definition at the clinical level. Shock is a bit like obscenity – after a while, you know it when you see it.

 EM in 5: Shock

To better understand and manage patients in shock, we can think about splitting them into 4 categories: Hypovolemic, Cardiogenic, Distributive, Obstructive.

 The general approach to the patient in shock

"Permissive hypotension" in trauma: Principle that guides the fluid resuscitation of traumatic patients who arrive hypotensive to stay somewhat hypotensive until blood loss is source-controlled.

RUSH (“Rapid Ultrasound for Shock”) Protocol

One of multiple described ultrasound protocols for evaluation of patients presenting to ED with undifferentiated hypotension. Provides a framework for rapid and systematic evaluation of cause of hypotension •Three categories •Pump – Cardiac evaluation •Tank – Volume status •Pipes – Vascular system •Equipment: Ultrasound machine with phased array (3.5-5MHz) and linear probes (7.5 – 10MHz).

Albumin versus normal saline

Crystalloid vs colloid - no clear advantage of either

Some Miscellaneous Tidbits About Shock

The abnormally low cardiac output that we term "shock" can result from several causes. Understanding how shock can develop and how the cardiovascular system's regulatory mechanisms respond is interesting in its own right, and it also provides some useful insights into the normal functioning of the regulatory mechanisms...

Choosing the right vasopressor agent in hypotension

Persistent hypotension results in impaired tissue perfusion and is often a late and ominous indication of decompensated shock. Correction of persistent hypotension is imperative, often requiring vasopressors and inotropes. When considering an agent for hemodynamic support, the following checklist can guide your choice...

Colloids vs. Crystalloids for Critically Ill Patients Presenting with Hypovolemic Shock

In ICU patients with hypovolemia requiring resuscitation, the use of colloids vs. crystalloids did not result in a significant difference in 28-day mortality; however, 90-day mortality was lower among patients receiving colloids.

Do colloids save lives in hypovolemic shock?

So, your patient's in shock: quick, give some fluids. But colloids or crystalloids? How to choose? They both raise blood pressure, they both improve organ perfusion -- but one's less filling, the other tastes great (what, you haven't tried them?).

Resuscitation Fluids

Fluid resuscitation with colloid and crystalloid solutions is a ubiquitous intervention in acute medicine. The selection and use of resuscitation fluids is based on physiological principles, but clinical practice is determined largely by clinician preference, with marked regional variation. No ideal resuscitation fluid exists. There is emerging evidence that the type and dose of resuscitation fluid may affect patient-centered outcomes.

Shock

At the cellular level, shock hypoxemia causes cell membrane dysfunction leading to intracellular edema and leakage, as well inability to regulate cellular pH. This causes progressive acidemia, which in turn, have severe systemic effects on multiple organ systems.

Shock Review: Goals of Therapy

While simple in theory, the complexity of the body's response to shock and its therapies can make realtime goal-directed management of shock surprisingly challenging.

Shock Review: Mechanisms and Therapies

Need a mnemonic? Authors propose "VIP": Ventilation (oxygen, intubation etc), Infusion (volume resuscitation), Pump (vasoactive drugs) to manage people in shock.

The Ongoing Controversy: Crystalloids Versus Colloids

There is still much debate over the optimal fluid to use for resuscitation. Different studies have indicated either crystalloid or colloid is the ideal intravenous solution to administer, based on mortality or various physiological parameters. Older studies found differences between crystalloids and colloids. However, with the evolving science of fluid administration, more recent studies have shown no differences in patient outcomes.