TRANSITION SERIES Topics for the Advanced EMT CHAPTER Shock 35

TRANSITION SERIESTRANSITION SERIES

Topics for the Advanced EMTTopics for the Advanced EMT

CHAPTERCHAPTER

ShockShock

3535

ObjectivesObjectives

• Review the rates for hypoperfusion and shock.

• Review aerobic and anaerobic metabolism.

• Discuss the pathophysiological basis for the stages of shock.

• Define treatment strategies for a patient with shock.

IntroductionIntroduction

• “Shock” coined in 1743 to represent what happens at the cellular level when perfusion is bad.

• Now it has varied meanings, so the term “hypoperfusion” has been introduced.

EpidemiologyEpidemiology

• Since “shock” is a response to another body dysfunction, there is not a clear estimation of “shock” rates.

• It is known, though, that when a shock state does occur (for whatever reason), the death rate is normally >20%.

• Some etiologies of shock cause 90% mortality.

PathophysiologyPathophysiology

• Hypoperfusion can occur due to multiple etiologies.– Cardiac– Volume– Vascular

Pathophysiology (cont’d)Pathophysiology (cont’d)

• In any instance, the final common pathway is deterioration of cellular oxygenation.– Aerobic metabolism– Anaerobic metabolism

Etiologies of Shock

Etiology of shock: fluid loss

Etiology of shock: pump failure

Etiology of shock: vasodilation

Pathophysiology (cont’d)Pathophysiology (cont’d)

• Stages of shock– Initial stage– Compensatory (nonprogressive) stage

Compensatory mechanisms

– Progressive (decompensatory) stage– Refractory (irreversible) stage

Compensatory Mechanisms in Hypoperfusion

Effects of Shock on Body Organs and Systems

Recognizing the severity of shock

Assessment FindingsAssessment Findings

• Depending upon stage of shock:– Tachycardia and tachypnea– Anxious, aggressive, altered mental

status– Narrowing pulse pressure– Muscles become weak, then limp

Assessment Findings (cont’d)Assessment Findings (cont’d)

• Depending upon stage of shock (continued)– Skin becomes cool and pale, typically

diaphoretic– Final stages will have a dropping systolic

blood pressure, excessive tachycardia, unresponsiveness and death

Categories and types of shock

Characteristics of the Major Categories of Shock

Emergency Medical CareEmergency Medical Care

• Spinal immobilization considerations– Traumatic incidents

• Airway considerations– Ensure open airway.– Maintain airway if needed.

Emergency Medical Care (cont’d)Emergency Medical Care (cont’d)

• Breathing considerations– Use high-flow oxygen if breathing

adequately.– PPV at either 8-10 or 10-12 (based on

pulse).

Emergency Medical Care (cont’d)Emergency Medical Care (cont’d)

• Circulatory considerations– Importance of pulse checks.– If CPR warranted, push hard and fast.– If major bleed present (whether arterial

or venous), control it as soon as possible.

• Other considerations– Maintain normothermia.– Body positioning.

Emergency Medical Care (cont’d)Emergency Medical Care (cont’d)

• Intravenous therapy– Do not delay transport to initiate an IV.– If volume expansion is needed, use a

large-bore catheter such as a 14 or 16 gauge.

– Administer IV fluids based on the clinical presentation and as your protocol allows.

Emergency Medical Care (cont’d)Emergency Medical Care (cont’d)

• Volume Loss Etiology (Hypovolemia)– Uncontrolled hemorrhage - infuse fluid

at a rate to maintain a systolic blood pressure of 80 to 90 mmHg or until radial pulses are able to be palpated.

– Controlled hemorrhage - infuse fluid to maintain the systolic blood pressure above 90 to 100 mmHg.

Emergency Medical Care (cont’d)Emergency Medical Care (cont’d)

• Vasodilation Etiology– Increase vascular resistance by

decreasing the vessel size.– Fill the vessel with fluid. – As an Advanced EMT, you will not likely

be able to administer vasopressors to constrict vessels; however, you can infuse fluids to fill the vascular space.

Emergency Medical Care (cont’d)Emergency Medical Care (cont’d)

• Cardiogenic Etiology– Typically the patient is normovolemic

and is experiencing difficulty in moving the existing volume of blood.

– Restrict fluid administration to a keep-open rate once the intravenous line is initiated.

Case StudyCase Study

• During a local cage-fighting event, one of the fighters was lifted and thrown down onto the mat, landing on his head and back. The fighter quit moving so you were called in to assess the patient. He is a young male, 22-23 years old, 185 pounds, very muscular.

Case Study (cont’d)Case Study (cont’d)

• Scene Size-Up– Standard precautions taken.– Scene is safe, obvious struggle with the

fighting. – Patient lying supine on floor of ring.– No entry problems, egress may be

hampered due to large audience present.

Case Study (cont’d)Case Study (cont’d)

• Primary Assessment Findings– Patient responsive.– Airway appears open, patient able to

speak.– Breathing is rapid and shallow, breath

sounds present.– Carotid and radial pulses present, radial

very weak.

Case Study (cont’d)Case Study (cont’d)

• Primary Assessment Findings– Peripheral skin is warm, diaphoretic.– No major bleeds or angulations noted,

patient not moving extremities.

Case Study (cont’d)Case Study (cont’d)

• Is this patient a high or low priority? Why?

• What interventions should be provided at this time?

Case Study (cont’d)Case Study (cont’d)

• What is the significance of the radial pulse being weak as compared to the carotid?

• What could be the etiologies of shock that could create this finding?

Case Study (cont’d)Case Study (cont’d)

• Medical History– Patient states none

• Medications– Various muscular training supplements

• Allergies– None

Case Study (cont’d)Case Study (cont’d)

• Pertinent Secondary Assessment Findings– Pupils reactive to light.– Airway patent and maintained by the

patient.– Breathing is rapid, alveolar sounds

diminished.– Peripheral pulse now absent, carotid

now becoming weaker.

Case Study (cont’d)Case Study (cont’d)

• Pertinent Secondary Assessment Findings (continued)– Skin warm and dry, no motor or sensory

motion below shoulders.– B/P 100/50, HR 62, RR 26.

– SpO2 95% on room air, 99% on oxygen.

Case Study (cont’d)Case Study (cont’d)

• Is this patient in a state of shock?• If yes, what stage of shock?• Are there now findings that would

cause you to refine your field impression?

Case Study (cont’d)Case Study (cont’d)

• What normal compensatory mechanism for shock is not active in this patient?

• Why would this etiology of shock cause the patient's respiratory status to be what it is?

Case Study (cont’d)Case Study (cont’d)

• Care provided:– Patient kept supine.– High-flow oxygen via NRB mask.– Full spinal immobilization done very

carefully.– Paramedic intercept started early.– Patient packaged and taken to ambulance

via wheeled cot.– Transport to hospital initiated.

SummarySummary

• Hypoperfusion is going to be one of the most common syndromes seen by the Advanced EMT.

• Since this is the final common pathway for all types of shock, the Advanced EMT must be able to recognize the cause of shock – not just the symptoms, in order to provide the best care.