Shock Flashcards
What is the definition of shock?
Inadequate peripheral tissue perfusion which leads to decreased oxygen and nutrient provision for tissue cells
What are the 4 stages of shock?
- Initial
- Compensatory
- Progressive
- Refractory
What is the initial state?
- Hypoxia which leads to decreased ATP produced by the mitiochondria
- this damages the cell membranes and they start to leak into the extra-cellular fluid
- anaerobic respiration occurs and pyruvic acid and oflactic is produced
What is the compensatory state?
- neural, hormonal, biochemical mechanisms occur to reverse the initial stage
- hyperventilation occurs to get rid of the carbon dioxide to corrector the pH
- cushings reflex (increased blood pressure) because increase in adrenaline(increases heart rate) and noradrenaline(causing vasoconstriction)
- the renin-angiotensin axis which conserves fluid
- this is all to divert fluid to the heart, brain and lungs
What is the progressive state?
- compensatory mechanisms fail
- anaerobic metabolism continues and there is potassium effluent and and sodium influx
- metabolic acidosis leads to blood pooling in the capillaries
- the increase of hydrostatic pressure and histamine release leads to leakage of fluid and protein into the surrounding area
- prolonged vasoconstriction leads to vital organ compromise
What is the refractory state?
- Vital organs fail and shock cannot be reversed
What are the 6 types of shock?
- Hypovolaemic
- Cardiogenic
- Neurogenic
- Obstructive
- Septic
- Anaphylactic
What is hypovolaemic shock?
- Decreased volume circulating through the blood
- causes include haemorrhage, ruptured ectopic pregnancy, burns, acute pancreatitis
What is cardiogenic shock?
- inability of the heart to pump effectively
- associated with myocardial infarction, cardiomyopathy, arrythmias
What is neurogenic shock?
-trauma to spinal cord leading to loss of motor and autonomic reflexes
What is obstructive shock?
The flow of blood is stopped so this impedes circulation
- cardiac tamponade
- tension pneumothorax
- pulmonary embolism
- aortic stenosis
What is septic shock?
Severe sepsis and hypotension that cannot be reversed with fluids
What is the criteria for septic shock?
- Systolic BP of less than 90 mmHg or mean arterial BP of less than 60 mmHg
- Tachypnoea>20 breaths per minute
- WCC of less than 4000 cells or more than 12000 cells
- HR>90 beats per minute
- Temp: >38 degrees and <36 degrees
What does the pneumonic OVERS mean?
- Oxygen administration and airway
- Volume resus: crystalloids and colloids
- Early antibiotic administration
- Rapid source identification and control
- support major organ dysfunction
When should we start AB treatment if the patient is in septic shock?
At least an hour into the sepsis
- broad spectrum
- do blood culture before you administer AB
What is the management for Hypovolaemic shock?
- Full blood count-Haematocrit
- U&E
- Creatinine
- Troponin T(cardiac enzymes)
- Arterial blood gas(metabolic acidosis)
- CVP line to check fluid resus
- Give fluid-1L crystalloid over 1 hour
What is the management for cardiogenic shock?
- ECG
2. Troponin T
What is the Mx for obstructive shock?
- Tension pneumothorax-insert 14G cannula in the 2nd intercostal space midclavicular line
- Cardiac tamponade: 500ml normal saline IVI, IV dopamine infusion 5mcg/kg/min, pericardiocentesis
- Pulmonary embolism: FBC,U&E,ECG,ABG, Pain relief, fluid resus and inotropic support, IV 5000U of heparin bolus, gold standard=pulmonary angiogram
What is cardiac tamponade/pericarditis?
Fluid or effusion surrounding the heart presenting with
- muffled heart sounds
- jugular venous distension
- diffuse ST elevation
- hypotension
What is the management of neurogenic shock?
- Manage the site of trauma
- Do neuro exam
- Do C-spine X-ray up to C7/T1 for swimmers view/open mouth view if C1/2 injury
- Thoracivc and lumbar spine X-ray
- CT scan
- MRI scan later
- Fluid resus and compare and titrations according to urine output
- Use vasopressors if the fluid resus is not working
- Refer to neuro/ortho
What is the management of anaphylactic shock?
- Stop the allergen
- Gastric lavage and activated charcoal if drug was ingested
- Obtain airway by intubation
- Give fluids-hartmans solution of normal saline 2L
- Give adrenaline
- Give glucagon if adrenaline has failed or if adrenaline is contra-indicated-IHD, pregnancy, severe HPT
IV/IM 0,5-1mg - Give an anti-histamine- Promethazinee 25mg IM/IV
- Cimetidine 200/400mg IV bolus if above does not work
- Salbutamol
- Hydrocortisone (corticosteroid) 200-300 mg IV bolus
What is the management of septic shock?
- Identify site of infection
- FBC, U&E,Creatinine,ABG,ECG,CXR, Urine C/S
- Rapid infusion 1-2L crystalloids and CVP line insertion
- Give antibiotics- 3rd generation cephalosporin- 1g IV ceftriaxone or quinolone (ciprofloxacin 200 mg)
What is a CVP line?
- can be placed at 3 different points: jugular, subclavian and femoral
- can be used to give fluids, medication, chemotherapy and for longer operations
Give an example of an aminoglycoside
-gentamycin
Give an example of a quinolone
-ciprofloxacin
Define angioedema?
- edema of the deeper layers of the skin
- usually non-pruritic
- can be/without numbness and pain
What is urticaria?
-oedematous and pruritic plaques with raised edges and a pale center
