Haemorrhage Flashcards
Pulse pressure
SBP - DBP
Mean Arterial Pressure
DBP + 1/3 PP
Haemorrhage definition
Disruption or leakage from the circulatory system
Can be external, internally concealed or internally revealed
External Haemorrhage
Soft tissue, can be arterial, venous or capillary level.
The seriousness of the injury is related to vascular disruption and amount of blood lost
Internal Haemorrhage
occurs in a body cavity, caused by blunt or penetrating trauma
Internal Haemorrhage signs and symptoms
light headed, N+V, rapid weak thready pulse, rapid resps, pale cold clammy, thirsty, history, evidence from scene, blood from cavity is a bad sign
Haemostasis
blood clotting that stops haemorrhage therefore stopping bleeding
The Clotting Process
Vascular Spasm: vessel walls constrict due to nervous reflexes, minimising blood loss and allowing platelet plug to occur
Platelet Plug Formation: platelets adhere to collagen under the epithelium becoming sticky and attracting other platelets which forms a temporary plug
Blood Coagulation: Extrinsic pathway is initiated by liquid blood making contact with damaged tissue. Intrinsic pathway is initiated by liquid blood making contact with a foreign surface
Coagulation pathway
- formation of prothrombin activator
- conversion of prothrombin to thrombin
- conversion of soluble fibrinogen which is converted to fibrin by thrombin
Drugs affecting clotting
Platelet inhibitors - stops production of thromboxane A required in platelet plug formation
Anticoagulants - interferes with Vitamin K dependent clotting factors
Thrombolytics - converts plasminogen into active plasmin-clot dissolving
Treatment of Haemorrhage
Firm, direct pressure without compromising circulation
Place more bandages over the top if still bleeding
Use a BP cuff or bandage if still bleeding
Shock Definition
a continuning process defined by a chain of event which leads to widespread reduction in tissue perfusion leading to impairment of cellular metabolism
Low systemic vascular resistance and perfusion pressure inadequate to move oxygen
Stages of Shock
Compensatory
Decompensatory
Irreversible
Compensatory Shock
Increase HR and PVR and vessels dilate to maintain BP
Blood shunts from less vital organs to the vital ones
Signs of Compensatory Shock
Tachycardia
Slightly Pale
BP remains stable - slight rise in SBP with PP increasing
Decompensating shock
body can’t maintain BP, SBP drops first as it is more reliant on CO
decreases in cerebral blood flow and partial pressure of O2
Blood shunts to vital organs, body systems are shutting down
Decompensating shock signs
hypotension - pulse pressure reduces, tachycardia, tachypnoea - to get more oxygen in, pale and diaphoretic, developing ACS, reduced urine output, delayed capillary refill
Irreversible shock
cellular ischaemia and necrosis leads to release of contents into circulation
everything shuts down
Irreversible signs
bradycardia life threatening dysrhythmias severe unabated hypotension abnormal resp patterns ACS cyanosis and mottling of skin death
Absolute Fluid Loss
water and minerals lost due to dehydration, diarrhoea and vomiting, reduced fluid intake, excessive diuresis
Absolute Fluid Loss signs and symptoms
altered conscious, cool pale clammy, dizziness, nausea and vomiting, increased resps, increased HR, hypotension as late sign
Relative Fluid Loss
BP remains the same, but blood vessels capacity increase due to vasodilation e.g. anaphylaxis
Relative Fluid Loss signs and symptoms
skin may be warm and flushed due to pooling in periphery, tachypnoea, tachycardia, hypotension
