Shock Flashcards
what is the pathophysiology of shock?
MAP below necessary = slow flow to organs (thrombus formation) = inadequate perfusion for cellular metabolic requirements (= acidosis and lactate)
what are the consequences of inadequate perfusion in shock?
o Systemic Acidosis (pH < 7.35), further worsening global enzyme function and cellular performance
o Microcapillary thrombus with patchy tissue injury and even large vessel thrombus with organ infarction
o Eventual cellular necrosis results in mortality
what are the 3 main windows for recognition in shock?
Skin = mottling
Brain = GCS <15
Kidney = Urine Output <0.5ml/kg/h
4th? - side stream dark field microscopy of sublingual microcirculation
how can shock be confirmed?
lactate levels
>2mmol/L
what is the management of shock?
Rapid assessment
Fluid challenge
what are the features of A/B history in a shock ABCDE?
Dyspnoea
Cough
Allergies
what are the features of C history in a shock ABCDE?
Chest/Abdo pain, oliguria, medication
what are the features of D history in a shock ABCDE?
confusion
what are the features of E history in a shock ABCDE?
trauma, fever, vomiting, haematemesis, melena, diarrhoea, urinary sx
what are the features of examination of A/B in a shock ABCDE?
Hyper-resonance
Oedema
Consolidation
what are the features of examination of C in a shock ABCDE?
Peripheries cool or warm, JVP distension, murmur
what are the features of examination of D in a shock ABCDE?
Neurological signs
what are the features of examination of E in a shock ABCDE?
PR Exam Dehydration Oedema Trauma Fever Abdo Exam
what action may be required for A/B in ABCDE of shock?
pneumothorax»_space;> needle thoracocentesis
what action may be required for C in ABCDE of shock?
Hypovolaemia»>fluid challenge
what action may be required for E in ABCDE of shock?
Sepsis»>antibiotics
what investigations are required in A/B in ABCDE of shock?
ABG
what investigations are required in C in ABCDE of shock?
ECG, Bloods, Echo/CT
what investigations are required in D in ABCDE of shock?
Xrays/CT
what investigations are required in E in ABCDE of shock?
Sugar, urine, swabs, FAST/CT
what are the 4 different types of shock?
Cardiogenic
Distributive
Obstructive
Hypovolaemic
what is the pathophysiology of cardiogenic shock
Reduced SV + HR = reduced CO and MAP.
Compensatory increase in SVR
What are the causes of Cardiogenic shock?
HR - arrhythmia, poisoning
SV - MI, cardiomyopathy, valve failure
what are the clinical features of cardiogenic shock?
cool, clammy hands (peripheries)
What is the management of cardiogenic shock?
Arrhythmia - Drugs +/- cardioversion
Poisoning - Drugs +/- dialysis
MI - drugs +/- PCI
Cardiomyopathy/Valve Failure - Drugs +/- surgery
what is the pathophysiology of distributive shock?
Vasodilation leads to reduced SVR and MAP.
CO increases to compensate (via increased HR and SV)
what are the 2 types of causes of distributive shock?
Inflammatory
Neurogenic
what are the causes of inflammatory distributive shock?
Sepsis
SIRS - pancreatitis and Burns
Anaphylactic shock
what are the causes of neurogenic distributive shock?
Spinal cord damage
Iatrogenic
what is the clinical features of distributive shock?
warm red peripheries, bounding hyperdynamic circulation
what is the management of inflammatory distributive shock?
Sepsis - Antibiotics +/- noradrenaline
SIRs - supportive
Anaphylaxis - adrenaline
what is the management of neurogenic distributive shock?
Spinal cord - neurosurgery
Iatrogenic - support +/- vasopressors
what is the pathophysiology of hypovolaemic shock?
Reduced blood volume = Lower venous return to the heart = reduced SV = reduced CO and MAP
increased HR and SVR to compensate
what are the clinical features of hypovolaemic shock?
signs of haemorrhage, dehydration, tachycardia, cool clammy peripheries
what are the causes of haemorrhage in hypovolaemic shock?
Trauma - overt haemorrhage, pelvic fracture, long bone fracture, abdominal visceral, intrathoracic
GI bleeding
Post op bleeding
what are the causes of dehydration in hypovolaemic shock?
- GI loss (diarrhoea, vomiting, stoma, starvation)
- Epithelial loss (burns)
- renal/cellular loss (Addisonian crisis, diabetic ketoacidosis)
what is the management of haemorrhage hypovolaemic shock?
temporising measures (pressure, splint, binding, sengstaken) Find and stop bleeding (surgery, endoscopy) Cross match, blood, blood products
what is the management of dehydration hypovolaemic shock?
- Fluid electrolytes
- specialist unit care
- Steroids/insulin
what is the pathophysiology of obstructive shock?
Obstruction to cardiac outflow (otherwise similar to cardiogenic shock) – leading to backflow
what are the causes of obstructive shock?
cardiac tamponade
tension pneumothorax
PE
what are the clinical features of obstructive shock?
raised JVP, distended neck veins
what are the causes of cardiac tamponade in obstructive shock?
Trauma
Aortic Dissection
what are the causes of Tension pneumothorax in obstructive shock?
Trauma
Pleural Pathology
what are the causes of PE in obstructive shock?
Stasis
what is the management of cardiac tamponade in obstructive shock?
Pericardiocentesis +/- Thoracotomy +/- Surgery
what is the management of tension pneumothorax in obstructive shock?
Thoracentesis + Thoracostomy +/- surgery
what is the management of PE in obstructive shock?
Anticoagulation +/- Thrombolysis or direct lysis
what is the 1st stage of the major haemorrhage protocol?
Call blood bank and state Major haemorrhage
what is the 2nd step of the major haemorrhage protocol?
Send urgent blood samples
Blood bank issues blood
Resus Patient
What blood products does the blood bank issue in major haemorrhage protocol?
4 units red cells
4 units FFP
1 unit platelets
What is the Resus approach in major haemorrhage protocol?
ABCDE Large bore IV access IV fluids Call for senior help Transfuse red cells/FFP/platelets
what should occur after bleeding is controlled in the major haemorrhage protocol?
notify blood bank to stand down
what is the 3rd stage of major haemorrhage protocol if bleeding continues after initial transfusion?
Repeat blood samples
Transfuse further RVC and FFP at 2:1 ratio (1:1 if trauma)
Cryoprecipitate if fibrinogen <1g/L
Consider further platelets
how should blood results be maintained in major haemorrhage protocol?
Hb>80g/L
APTT and PT ratio <1.5
Platelets >50x10^8/L
Fibrinogen >1.5g/L
what is the specific feature of management in post partum haemorrhage?
fibrinogen replacement early
what is the specific feature of management in trauma haemorrhage?
tranexamic acid
what is the specific feature of management in variceal bleeding haemorrhage?
coagulopathy before bleed, predispose and make it difficult to stop
what is the specific feature of management in ruptured AAA haemorrhage?
surgical emergency
