Control of blood pressure/shock Flashcards
(24 cards)
What is blood pressure (BP) critical for?
Tissue perfusion, supplying oxygen/nutrients and removing waste.
What does mean arterial blood pressure (MABP) depend on?
Cardiac output (CO) and total peripheral resistance (TPR).
What is shock?
A condition when BP drops too low, leading to inadequate tissue perfusion.
What injuries did John Doe sustain?
Multiple fractures (femur, tibia/fibula) and lacerations.
What are the signs of shock seen in John Doe?
- Pale, cold peripheries
- Heart rate (HR): 120 bpm (tachycardia)
- BP: 90/50 mmHg → MABP = 63 mmHg
What is the immediate concern in shock?
Hypotension and potential cardiovascular collapse.
What is the formula for Mean Arterial Blood Pressure (MABP)?
MABP = CO × TPR.
What factors constitute cardiac output (CO)?
HR × Stroke Volume (SV).
Where are baroreceptors located?
In the carotid sinus and aortic arch.
What do baroreceptors detect?
Changes in blood pressure.
How do baroreceptors respond to BP changes?
Send signals to the brainstem to adjust HR, SV, and TPR.
What is the role of the autonomic nervous system (ANS) in BP regulation?
Reflexively adjusts HR, SV, and TPR.
What happens to compensatory mechanisms in shock due to significant blood loss?
They fail, leading to persistent hypotension.
What is the immediate response to hemorrhage and hypotension?
Baroreceptor Reflex increases HR, SV, and vasoconstriction.
What symptoms are associated with the baroreceptor reflex?
- Tachycardia
- Cold skin
- Pale complexion
What occurs during the intermediate response to blood loss?
Fluid moves from interstitial tissues into capillaries to restore blood volume.
What hormones are involved in long-term volume replacement after hemorrhage?
- Antidiuretic hormone (ADH)
- Renin-Angiotensin-Aldosterone (RAA) system
What is the ‘Golden Hour’ in shock management?
A critical period where rapid intervention improves survival.
What are the three types of shock?
- Hypovolemic Shock
- Distributive Shock
- Cardiogenic Shock
What causes hypovolemic shock?
Blood/fluid loss (e.g., hemorrhage, dehydration).
What causes distributive shock?
Severe vasodilation (e.g., sepsis, anaphylaxis).
What causes cardiogenic shock?
Heart failure (e.g., myocardial infarction).
Maintaining MABP through compensation is key to what?
Survival.
Severe blood loss requires what type of intervention?
Urgent intervention to restore perfusion and prevent multi-organ failure.
