Shock Flashcards
Risk factors in early pregnancy
Ectopic pregnancy
Abortion
Hypermesis
Risk factors in later pregnancy
Haemorrhage from
- placenta praevia, abruption, ruptured uterus, vasa praevia
Risk factors postpartum
Haemorrhage related to
- atonic uterus
- retained palcenta
- genital tract trauma
- inverted uterus
- coagulation disorders
Definition of shock
Life threatening condition
“Mean arterial blood pressure inadequate to meet the needs of the tissues”
“Tissue hypoperfusion”
Inadequate organ/tissue perfusion (global)
Oxygen demands not met by delivery
Treatment for Shock
CO ( cardiac output) = Stroke Volume X Heart Rate
Signs of hypovolaemic shock
- tachycardia
- weak pulse
- rise in disatolic bp
- low urine output
- cool periphery
- increased RR
- Nausea
- Sweating
- increased blood glucose
- anxiety
Medical investigation
Central venous pressure (CVP)
Monitor body fluid volume
Evaluate effectiveness of fluid replacement therapy
Arterial Line –BP & blood gas analysis (ABG)
Blood tests
FBC (Hb, haematocrit, red cell count)
U&Es, glucose, clotting screen
Electrocardiography (ECG)
Treatment of shock
Assist oxygenation of organs/tissues
Venous access
2 large-bore peripheral cannulae
Central line if other access difficult
Fluid replacement
Blood, blood products, clotting factors
Consider transfusion risks + consent issues
Deal with the CAUSE!
Oxytocics (ergometrine, oxytocin, carboprost)
Blood for transfusion
Red cells progressively deteriorate, taking up water and releasing intracellular contents
Change in Na+ and K+ levels in stored blood
Platelets and white cells tend to aggregate
Must use blood filter to prevent entry into patient
Stored blood deficient in clotting factors
With large transfusions, may need to consider fresh frozen plasma and/or cryoprecipitate
Preservative added to bag (citrate phosphate dextrose) reduces its pH from 7.4 to 7.0
The air free bag prevents aerobic metabolism taking place, BUT anaerobic metabolism occurs
Lactic acid produced (more with longer storage)
pH falls to 6.6-6.8 after 2-3 weeks of storage
Cardiogenic shock.
Aim - improve myocardial contractility, maintain blood pressure and tissue perfusion/oxygenation
Oxygen therapy
Morphine/diamorphine (dilate coronary BVs; analgesia; sedation; risk of respiratory impairment)
Antiemetics
12-lead ECG + cardiac monitoring
CVP monitoring
Arterial ‘line’ for monitoring BP
Inotropes (drugs to improve heart muscle contractility), e.g. dobutamine
Vasodilator drugs
Glyceryltrinitrate (GTN)
Distributive shock
Systemic vascular resistance is lowered due to vasodilation of arterioles
Sepsis/septicaemia Neurogenic shock (loss of sympathetic tone)
Anaphylaxis (acute allergic reaction)
Person feels warm to touch (peripheral vasodilation) and may appear flushed/red
BP cannot be maintained, so organ/tissue perfusion is inadequate and heart attempts to compensate
Inflammatory response has been initiated (in sepsis or anaphylaxis)
Neurogenic shock – clinical picture different, as damage is to the nervous system; may be bradycardic
Treatment for septic shock
Identify the infective organism (blood culture; microbiology swabs or samples)
Identification of ‘source’ of infection, e.g. retained tampon or swab, retained products of conception, fetal tissue
Antibiotic therapy (IV at first) Oxygen therapy Respiratory support Drugs to improve cardiac function Antipyretic therapy, e.g. paracetamol, cooling measures
Toxic shock syndrome
Staphylococcus aureus in the human body
Nose, vagina, axillae, perineum, GI tract
During menstruation, vaginal pH raised (less acidic); this diminishes growth of normal commensals (Lactobacilli) and encourages that of potential pathogens
Anaphylatic shock: Treatment
Airway and breathing support
Adrenaline ( epinephrine), steroids, antihistamines
Anaphylatic shock:
Risks
Bronchoconstriction + airway obstruction
Collapse + cardiorespiratory arrest
Common triggers
Foods; food additives; drugs; environmental agents
Signs & symptoms
Widespread oedema; breathing difficulty; cardiac arrhythmia; generalised rash; GI disturbance
