shock abdul.kader weiss m.d chirurgie generale et viscerale /chirurgie coelioscopique d.e.s,...
TRANSCRIPT
SHOCK
Abdul.Kader WEISS M.DCHIRURGIE GENERALE ET VISCERALE /CHIRURGIE COELIOSCOPIQUE
D.E.S , A.F.S ,A.F.S.A , DU / FRANCE
Reference :Editors: Pierce A. GraceNeil R. Borley / Title: Surgery at a Glance 2ed
Blackwell ScienceEditors : Seymour i. Schwartz, M.D. / Title :Principles of Surgery Companion Handbook
McGraw-Hill Companies, Inc
SHOCK• SHOCK IS A PATHOPHYSIOLOGIC CONDITION CLINICALLY
RECOGNIZED AS A STATE OF INADEQUATE TISSUE PERFUSION. • THERE ARE FOUR DISTINCT CATEGORIES:
– HEMATOGENIC– NEUROGENIC– VASOGENIC– CARDIOGENIC
• It is clear that shock is a SYSTEMIC DISORDER that disrupts vital organ function as the eventual result of a variety of causes.
• Whereas hemorrhagic or traumatic shock is characterized by global hypoperfusion, septic shock may be associated with hyperdynamic circulation resulting in a maldistribution of regional or intraorgan blood flow.
KEY POINTS
• Identify the cause early and begin treatment quickly.
• Shock in surgical patients is often over looked-unwell, confused, restless patients may well be shocked.
• Unless a cardiogenic cause is obvious, treat shock with urgent fluid resuscitation.
• Worsening clinical status despite adequate volume replacement suggests the need for intensive care.
PATHOPHYSIOLOGY
Many conditions can lead to an inadequate delivery of oxygen to vital structures of the body.
An aide-mémoire can be categorised as :● Decrease in oxygen uptake by the lungs● Reduced venous return● Impaired cardiac function● Reduced arterial tone● Impaired organ autoregulation● Decreased oxygen uptake and utilisation by tissues
COMMON CAUSES
HYPOVOLAEMIC SHOCKTRUE LOSS COMMON EXAMPLES
BLOOD LOSS GASTROINTESTINAL HAEMORRHAGE
RUPTURED AORTIC ANEURYSM
TRAUMA
PLASMA LOSS DIARRHOEA AND VOMITING
DIABETIC KETOACIDOSIS
PANCREATITIS
OSMOTIC DIURESIS
HYPONATRAEMIA
BURNS
FISTULA AND OSTOMIES
APPARENT LOSS COMMON EXAMPLES
VENODILATORS NITRATES, OPIATES, I.V LOOP DIURETICS
HYPONATRAEMIA GLUCOCORTICOID DEFICIENCY
CARDIAC SHOCKENDOCARDIAL INFECTIVE ENDOCARDITIS INFECTIVE ENDOCARDITIS
PAPILLARY MUSCLE RUPTURE
MYOCARDIAL VENTRICULAR FAILURE ISCHAEMIA/INFARCTION
MYOCARDITIS
DRUGS
TOXINS
CARDIOMYOPATHY
EPICARDIAL ACUTE TAMPONADE VENTRICULAR WALL RUPTURE
MALIGNANCY
POST SURGERY
CONSTRICTIVE PERICARDITIS VIRAL
TUBERCULOSIS
RADIOTHERAPY
ANAPHYLACTIC SHOCK
• Anaphylaxis is an acute reaction to a foreign substance to which the patient has already been sensitised.
• This leads to an immunoglobulin E (IgE) triggered rapid degranulation of mast cells and basophils .
• Anaphylactoid reactions have an identical clinical presentation but are not triggered by IgE and do not necessarily require previous exposure.
• Furthermore, they may not produce a reaction every time.
COMMON CAUSES OF ANAPHYLAXIS/ANAPHYLACTOID REACTIONS
ANAPHYLAXIS DRUGS (PROTEIN AND NON-PROTEIN) – COMMONLY PENICILLIN OROTHER Β LACTAM DRUGS, BLOOD PRODUCTS, AND IMMUNOGLOBULINS
VACCINESFOOD – ESPECIALLY NUTS, SHELLFISH
VENOMS – ESPECIALLY BEES, WASPS, AND HORNETS
PARASITES
CHEMICALS
LATEX
ANAPHYLACTOID COMPLEMENT ACTIVATION
COAGULATION/FIBRINOLYSIS SYSTEM ACTIVATION
DIRECT PHARMACOLOGICAL RELEASE OF MEDIATORS
EXERCISE INDUCED
IDIOPATHIC
TOXIC OR SEPTIC SHOCK
Gram –ve or, less often, Gram +ve infections. Retained tampon Abscess Empyema Surgical wound infection Osteomyelitis Cellulitis Infected burns Septic abortion
NEUROGENIC SHOCK
• A spinal lesion above T6 can impair the sympathetic nervous system outflow from the cord below this level.
• As a consequence both the reflex tachycardia and vasoconstriction responses to hypovolaemia are eliminated.
• The result is generalised vasodilatation, bradycardia and loss of temperature control
• As neurogenic shock leads to a reduction in blood supply to the spinal column, it gives rise to additional nervous tissue damage.
CLINICAL FEATURES
• HYPOVOLAEMIC AND CARDIOGENIC– Pallor, coldness, sweating and restlessness.– Tachycardia, weak pulse, low BP and oliguria.
• SEPTIC– Initially warm, flushed skin and bounding pulse.– Later confusion and low output picture.
INVESTIGATIONS AND ASSESSMENT
• Monitor pulse, BP, temperature, respiratory rate and urinary output.
• Establish good i.v. access and set up CVP line (possibly Swan–Ganz catheter as well).
• ECG, cardiac enzymes, echocardiography.• Hb, Hct, U+E, creatinine.• Group and crossmatch blood: haemorrhage.• Blood cultures: sepsis.• Arterial blood gases.
COMPLICATIONS
• ‘SIRS’ (systemic inflammatory response syndrome) may ensue if shock not corrected.
• Acute renal failure (acute tubular necrosis).• Hepatic failure.• Stress ulceration.
SIRS (SYSTEMIC INFLAMMATORY RESPONSE SYNDROME)
• SIRS (systemic inflammatory response syndrome) is a systemic inflammatory response characterized by the presence of two or more of the following:• hyperthermia >38°C or hypothermia <36°C• tachycardia >90 bpm• tachypnoea >20 r.p.m. or PaCO2 <4.3 kPa• neutrophilia >12 × 10*9 l–1 or neutropenia <4 × 10*9 l–1.
• Sepsis syndrome is a state of SIRS with proven infection.
• Septic shock is sepsis with systemic shock.
ESSENTIAL MANAGEMENT
• AIRWAY & BREATHING: Give 100% O2, sit up, consider ventilatory support if
necessary.
• CIRCULATION: Ensure good IV access, urinary catheter, monitor
cardiac rate and rhythm.
ESSENTIAL MANAGEMENT
DEAL WITH THE CAUSE OF THE SHOCK( e.g. stop the bleeding, drain the abscess, remove the source of the anaphylactic antigen, etc.).
ESSENTIAL MANAGEMENT
ANAPHYLACTIC I.V. FLUIDS. I.V. ADRENALINE. I.V. ANTIHISTAMINES. I.V. HYDROCORTISONE.
ESSENTIAL MANAGEMENT
CARDIOGENIC• Optimize rate and rhythm (e.g. cardioversion, drugs).
• Optimize preload (e.g. adequate volume, diuretics).
• Optimize afterload (e.g. vasoconstrictors/dilators).
• Optimize cardiac function (e.g. thrombolytic therapy, inotropes, assist devices).
ESSENTIAL MANAGEMENT
SEPTIC• Fluids to restore circulating volume.• Antibiotics or surgery.• Support cardiac function (e.g. inotropes).
ESSENTIAL MANAGEMENT
HYPOVOLAEMIC• Identify and arrest losses (may include surgery).
• Restore circulating volume (crystalloids, colloids or blood).
• Support cardiac function.
THANK YOUAbdul.Kader WEISS M.D