Shock and AnaphylaxisChapter 37

Written by: Melissa Dearing – LSC-Kingwood

Shock- Definition

Syndrome associated with an imbalance between the supply of essential nutrients, oxygen and substrate to the tissues of an organ and the metabolic demand of that organ.

Shock – Physiological Changes

Organism levelMust maintain adequate cardiac output in order to

supply cells and tissues with an oxygen-rich environment.

Cellular levelThe cells have to have oxygen to produce energyWithout oxygen the cells shift to anaerobic

metabolism and begin to produce lactic acid.

Cardiac Output

Shock state can be classified based on whether the inadequate cardiac output is related to a problem with:

Heart ratePreloadInotropyAfterload

Nutrients and O2

Cardiac output responsible for delivery of O2 and nutrients to tissue

2 Methods1: Some nutrients and O2 is dissolved n the blood2: Most nutrients and O2 are bound to blood cells

and carried to the tissues.

Blood Delivery to Tissues

Cardiac output carries O2 to the tissueTissue and cells uptake the oxygen Organ byproducts such as Co2 is then

released into the blood stream to be carried back to the lungs

3 Kinds of Shock

Hypovolemic Shock

Cardiogenic Shock

Distributive Shock

Hypovolemic Shock

Inadequate amount of preload to be pumped out of the R heart

Not enough blood to supply the entire body with nutrients and oxygen

Most common type of shock in childrenCalled hemorrhagic shock when RBC are lost from

the vascular spaceCan be due to extracellular fluid loss from: diarrhea,

vomiting or inadequate fluid intake

Cardiogenic Shock

Directly related to inotropy and afterloadDecreased cardiac output due to a problem

with the HR, contractility of the heart and afterload

HR may slow due to: hypoxia or heart block leading to ↓perfusion and shock.

Cardiac arrythmias that produce a HR that is too fast will also ↓perfusion.

Distributive Shock

Results from vasodilatation of the vascular bed

Loss of afterload and diastolic pressure

Can be caused by: SepsisNeurological insultAnaphylaxis Adrenal insufficiency

Assessment

ABC’s of resuscitationRapid assessment of the airwayBreathingCirculation

Assessment of Vital SignsPatient Hx

Assessment

ExaminationFeverSkin turgor (rigidity)BleedingBruisingTraumaCapillary RefillHemodynamic measurements

Assessment

ExaminationSkin

Pale? Cyanotic? Mottled? Cool?

Assessment

ExaminationBrain

LOC Response to commands Stuporous? Comatose? Anxiety?

Use Glasgow Coma Score

Assessment

Examination

Visceral organs

Monitor urine output

Adequate urine production is 1 ml/kg/hr

Ensures adequate renal blood flow

Assumption can be made that other organs are

receiving adequate flow

Monitoring

Continuous assessment leads to and follows therapeutic interventionMethods to detect physiological changes:

Arterial catheterCVP monitorPulmonary artery catheter

Treatment

RespiratoryVascularMyocardial FunctionPVRNutritional Status

Anaphylaxis

A type of shock that occurs from peripheral vasodilation.

Caused by body’s hypersensitivity to a particular antigen.

Examples: Latex Food Drugs Snake venom Bee stings

Anaphylaxis Pathology

Chemical mediators are released in response to antigen causing an inflammatory response.

Anaphylaxis Presentation

Varies with severitySkin eruptionRespiratory compromiseCardiovascular collapse

Similar to distributive shockVasodilation effects of histamine create a

decrease in the preload and afterload

Anaphylaxis Treatment

2 Phases

1st Phase: Vital Functions

Airway

Oxygen

Ventilation

Circulatory Function

2nd Phase: Combating Antigen Exposure

Limit antigen exposure

Give antihistamine and corticosteroids