Circulatory Insufficiency Flashcards
What is circulatory collapse
This is defined as the general or specific failure of the circulation, either cardiac or peripheral
What is a milder or preliminary form of circulatory collapse called?
Circulatory insufficiency
Types of circulatory collapse
1) CARDIAC circulatory collapse:-
Affects the vessels of the heart. Sometimes called Acute circulatory failure
2) PERIPHERAL circulatory collapse:-
Affects other vessels in the body. Sometimes called Shock, Peripheral vascular failure, Peripheral vascular shutdown.
List the causes of circulatory collapse
• Dehydration
• Surgery (from loss of excess blood)
•Heart conditions (MI, acute or chronic heart failure, ruptured or dissecting aortic aneurysm)
• Shock (Cardiogenic shock, hypovolemic shock, distributive or vasodilatory shock etc)
List the 5 types of circulatory shock
●Septic shock
●Anaphylactic shock
●Cardiogenic shock
●Hypovolaemic shock
●Neurogenic shock
What is the formula for measuring MAP and what is the normal MAP
MAP = (2 x DBP) + SBP/3
Normal range is 70-110mmHg
What is Septic shock
It is defined as persisting hypotension required vasopressors to maintain mean arterial pressure (MAP) of 65 mmHg or higher and a serum lactate level greater than 2 mmol/L, despite adequate volume resuscitation.
Usually caused by toxin releasing bacteria.
What are the clinical features of septic shock
● Fever, chills or rigor
● Confusion
● Anxiety
● Difficulty breathing
● Fatigue, malaise
● Nausea and vomiting
● Cold skin and extremities
● Delayed capillary refill
How works you manage septic shock?
Initial resuscitation
● 30 ml/kg of IV crystalloid fluid should be given within the first 3 hours
● Reassessment should include HR, BP, Arterial O2 saturation, RR, Urine Output ≥ 0.5 ml/kg/hr and CVP of 8 – 12 mmHg
● Additional fluids if the initial fluid therapy is insufficient
● Decrease in lactate levels may guide resuscitation
IV antimicrobials
● Emperical broad spectrum should be initiated within 1 hour and switched after sensitivity result is out.
What is anaphylactic shock
This is a widespread and very serious allergic reaction due to release of histamine.
What are the clinical features of anaphylactic shock and list the complications
Clinical Signs
●Bronchospasm
●Laryngeal oedema
●Urticaria
●Vascular collapse
Complications
●Brain damage
●Kidney failure
●Cardiogenic shock
●Arrhythmias
●Heart attacks/myocardial infarction
●Death
How would you manage anaphylactic shock
● Supportive measures including O2 therapy
● IV Epinephrine (Adrenaline)
● IV Glucocorticoid eg Hydrocortisone
● IV Anti-histamine
● IV β-agonist eg Albuler
What is cardiogenic shock
It may be defined as a state of inadequate tissue perfusion due to cardiac dysfunction or a state of end-organ hypoperfusion due to cardiac failure
What are the diagnostic criteria for cardiogenic shock
● Persistent (> 30 minutes) hypotension with systolic BP < 90 mmHg
● Reduction in cardiac index less than 2.2 L/min/m2
● Presence of elevated left ventricular filling pressure (PCWP > 18 mmHg)
● Signs and symptoms of end organ hypoperfusion
● Restlessness, confusion, cold cyanotic extremities, oliguria (< 30 ml/hr urinary output)
List the causes of cardiogenic shock
●Extensive acute myocardial infarction ( most common cause)
●Patients with previous impairment of ventricular function
●Myocardial injury causing systolic and diastolic dysfunction
●Decrease in cardiac output leading to decrease in systemic and coronary perfusion
Others
●Acute MI
●Left ventricular failure
●Papillary muscle rupture
●Acute ventricular septal defect
