SHOCK CAUSES AND MANAGEMENT

DEFINITION

Condition in which arterial blood flow/perfusion (Blood Pressure) is inadequate to meet tissue metabolic needs(maintain normal funtion of vital organs) In a healthy adult : Hypotension – arterial BP<90mmHg Shock – arterial BP <60mmHg Postural Hypotension- Drop in Systolic BP of 10 20mmHg or increase in Pulse rate of >15 with position change indicates hypovolemia

DIFFERENTIAL DIAGNOSIS OF SHOCK

1.

HYPOVOLEMIA 2. CARDIAC PUMP FAILURE 3. OBSTRUCTIVE 4. DISTRUBUTIVE - SYSTEMIC VASODILATATION GET HISTORY FROM RELATIVES

HYPOVOLEMIA

Loss of blood (hemorrhagic shock )

•

External hemorrhage

Trauma • Gastrointestinal tract bleeding

Internal hemorrhage

• • Hematoma Hemothorax or hemoperitoneum

Loss of plasma

Burns Exfoliative dermatitis

Loss of fluid and electrolytes External

Vomiting Diarrhea Excessive sweating Hyperosmolar states diabetic ketoacidosis, hyperosmolar nonketotic coma

Internal ("third spacing")

Peritonitis, Pancreatitis Ascites Intestinal obstruction

SYMPTOMS & SIGNS OF HYPOVOLEMIA – Blood Loss in a 70kg patient circulating blood volume is 5 liters (approx 70 ml/kg) Loss of Blood 15% (700-750 ml)- may produce little or no obvious symptoms 30% (1500ml) –mild tachycardia, tachpnoea and anxiety 30-40%-(1750ml) tachycardia (110-120beats per min) & marked hypotension 40% (2000ml) is life threatening • Plasma-5%body wt=3,500 ml Interstitial Fluid- 15% body wt = 10,500ml Intracellular volume= 40% body wt= 28,000ml

Hypovolemia from Diarrhoea/Vomiting- loss of water & lytes • Thirsty • Passes small amounts yellow urine • Dizzy on sitting (postural hypotension – 5% body wt loss =3500 ml Shock – 10% = 7000ml • Dry axilla & groin ( 1500ml water deficit) • Decreased tissue turgor- tongue has furrows,skin folds on pinching it , sunken eyeballs • Cool clammy extremities • Tachycardia • Weak or absent pulses • Empty neck veins in the supine position

Cardiogenic –Cardiac Pump Failure

Myocardial Infarction Cardiomyopathy Dysrhythmia

Tachyarrhythmia Bradyarrhythmia Acute valvular dysfunction (especially regurgitant lesions)

Rupture of ventricular septum or free ventricular wall

SIGNS & SYMPTOMS OFSHOCK PRODUCED BY PUMP FALURE HEART FAILURE • Sudden onset in VT/VFib • Chest pain in MI • Absent heart sounds or severe tachycardia • Raised JVP • Pedal oedema • Basal lung rales • Hepatojugular reflux

Obstructive shock -Decrease in Cardiac Filling

Tension pneumothorax Disease of pulmonary vasculature (massive pulmonary emboli, pulmonary hypertension) Pericardial disease (tamponade, constriction) Cardiac tumor (atrial myxoma) Left atrial mural thrombus Obstructive valvular disease (aortic or mitral stenosis)

SYMPTOMS OF OBSTRUCTIVE SHOCK

Raised JVP • Tension pneumothorax- absent breath sounds • Cardiac tamponade- distant heart sounds • Cardiogenic shock • Pulmonary embolism- chest pain, dyspnoea,hemoptysis,swollen calf, h/o immobilisation • Fluid overload

Distributive shock

Decrease in Systemic Vascular Resistance -

Vasodilatation

Septic shock Anaphylactic shock

,

Neurogenic shock Acute adrenal insufficiency Vasodilator drugs

Signs & Symptoms of Septic Shock

Usually gram-bacteria

(E.coli,Kleb,Pseuo,Prot.) Fever with chills, confusion, hyperglycemia in old/babies, diabetes, immunosuppressed, H/o recent surgery/manipuation of urinary,biliary,gynae system

S&S ANAPHYLAXIS

History of • Atopy • Insect bite esp wasp/bees • Food (peanuts, fish, eggs, seafood), • Drugs (penicillin, blood products, iron inj,

aspirin, NSAIDS, vaccines Urticaria, Oedema of skin and mucous membranes (angioedema), Wheezing- bronchospasm Stridor- laryngeal oedema Generalised itching, rhinitis, conjuntival redness

Neurogenic Shock

Causes– spinal cord injury, spinal anaesthesia, vasovagal- pain/fright h/ofainting,bradycardia,

ASSESSMENT OF SHOCK PATIENT Pt in

Cardiac Arrest-

call for help Moniter V fib –shock V tach- vagal manoeuvers- carotid sinus massage Adenosine-6mg iv fast followed by 5 ml saline flush Rpt in 1-2 min 12mg Flat line- CPR

ASSESSMENT OF SHOCK PATIENT Check

airway-

clear of blood/vomitus Start O2 or intubate if unconscious Auscultate

lungs

for air entry absent- tension pneumothorax / hemothorax? (percussion) rales – cardiac failure?

rhonchi- anapyhlaxis? LVFailure Auscultate

heart

distant sounds- cardiac tamponade?

Murmurs- acute valve problems?

JVP

flat- hypovolemia distended- cardiac failure?, PE,,Ten PT,,Cardiav Tamp?

Abdomen-

Fullness or pulsatile mass( ruptured aneurysm?) Tender – pancreatitis, perforation?

ASSESSMENT OF SHOCK PATIENT BP on both arms- different –dissection of aorta Fever- sepsis Pt cold clammy- hypovolemia? Cardiac failure?

Hypovolemia signs- skin/tongue turgor, sunken eyeballs,pallor Pedal oedema- cardiac failure Blood around mouth, malena? ( do PR) Urticaria, wheals, soft tissue swelling (anaphylaxis)

ASSESSMENT OF SHOCK PATIENT Investigations ABG ECG CXR Blood tests-Hb,WBC,platelets, Lytes,Blood sugar Creatinine,LFT, PT,PTT,Grouping & xmatch Cultures- Blood,urine,sputum ECHO Ultrasound abd , CT head

TREATMENT- HYPOVOLEMIA Diarrhoea. Vomiting

Insert 2 IV canulae (16 guage)-forearm, groin, central line Cut down Head down position Infuse normal saline or ringers lactate replace ½ the loss Insert Urinary catheter(Foley)- 1ml/kg Keep assesssing – dec IV when BP >90 and pt urinating

TREATMENT OF Heart Failure

Myocardial Infarction MONA Dopamine

Treatment of Pneumothorax

Insert chest tube in 2 nd intercostal space in midclavicular line Heimlich valve

Treatment of Sepsis

Antibiotics Correct cause of sepsis IV Fluids-leaky capillaries

Treatment of Anaphylaxis

Airway O2 mask/ intubate, / cricothyroidotomy with 14 guage canula or small ET tube Head down IV line Adrenaline 0.5 ml of 1:1000 soln IM or 5ml of 1:10,000 soln IV(0.1ml /kg body wt in children) slowly at 1ml/min till Bp recorded rpt every 10min acc to BP/pulse Hydrocortisone- 100-300mg IV H1 blocker antihistamine- promethazine 25-50mg IV Rpt 4-6hrly Aminophylline IV for bronchospasm (250mg IV)

DOPAMINE

Acts on diff receptors at diff doses Low dose- ( 0.5-2 microgm/kg/min) D1 on vascular smooth muscle causes vasodilatation of renal, mesenteric, cerebral, coronary vascular bed Mod dose (2-5 microgm/kg/min) Beta1 receptors positive ionotropic and chronotropic High dose - > 5 microgm/kg/min) Alpha receptors vasoconstiction and decrease blood flow

Hemodynamic calculations

CVP- = R atrial pressure = 1-7 mm Hg Pulm art pressure 15-30/3-12 mmHg PAWP= Pulm artery wedge pressure=3-12 mm Hg Cardiac index = cardiac output 4-6 l/min Body surface area =2.8-3.6l/min/sq.m

( sp gr of Hg=13.7)