A PowerPoint presentation on " Pharmacotherapy of Shock" suitable for Undergraduate medical students

1. DR. D. K. BRAHMA
ASSOCIATE PROFESSOR
DEPARTMENT OF PHARMACOLOGY
NEIGRIHMS, SHILLONG
Pharmacotherapy of Shock

2. Introduction
• Definition: Complex acute circulatory failure
associated with hypoperfusion of tissues, which is
incompatible with life if untreated and persisting for
more than a short time
• Initiated by – trauma, acute blood loss, depletion
of body fluids, severe infection or acute myocardial
dysfunction
• Mechanism of Shock: Hypovolemic, Cardiogenic,
Obstructive, Distributive and Septic

3. Classification of Shock
I. Hypovolemic or Oligemic:
i. Acute blood loss – burns and haemorrhage
ii. Dehydration and Sodium depletion – vomiting, diarrhoea, diabetic
ketoacidosis and Addison`s disease
II. Bacteremic endotoxic or septic: Severe infections in gm –ve bacteria
like E. coli, gm +ve resistant streptococci TSS. Deficiency of adrenal
gland function and vasopressin production
III. Cardiogenic shock: MI, Acute myocarditis and severe paroxysmal
tachycardia
IV. Anaphylactic shock
V. Neurogenic shock: Spinal anaesthesia, spinl chord injury, abdominal
and testicular trauma and perofration of hollow viscus
VI. Haemo-obstructive shock – massive pulmonary embolism

4. Hypovolemia Mechanism
Hypovolemia –
Reduction in circulating
blood volume
Reduced blood flow to
skin, kidneys and
intestines
Slowing of blood flow, local
haemoconcentration in
capillaries – thrombi
formation
Tissue hypoxia –
acidosis – liberation of
histamine, PG and
cardio depressant
peptides to circulation
Baroreceptor - Generalized
Compensatory Sympatho
adrenal discharge
Excessive
sympatho-
adrenal
discharge
Peripheral
vasoconstriction –
clinical manifestations.
Pooling of blood to
periphery, sluggish
micro circulation
Damage to intracellular
structures & fall in diastolic
BP – less coronary flow
(cardiogenic element of
shock) – also less cerebral
blood flow

5. Septic Shock Mechanism
Toxins released by
Microorganisms –
Exotoxins (TSS)
and Endotoxins
(gm –ve)
PHAGOCYTES and
ENDOTHELIAL CELLS
Release of
Cytokines - TNFα,
IL (IL-1β) and PAF
Release of LTs, PGs
and TXA2Injury to BV, inflammation,
vasodilatation increased
permeability, coagulation and
complement cascades and
fluid loss – hypovolemia
Depression of
myocardium and
Diffuse Cell
Injury, – multiple
organ failure

6. Clinical Picture
 Generally – pallor, sweating, cold extremities, rapid and thready pulse
and air hunger
 Cyanosis of the extremities
 Oliguria – urine output < 25 ml per hour for 4 hours or <500 ml/24
hours
 Mental changes (somnolence, confusion, restlessness) and acidosis
 Difference of temperature between rectum and skin
 Central venous pressure (CVP) - guide to hypovolemia estimation
 Fluid replacement – 10-20 ml per minute for 10-15 minutes
 No rise in of CVP – hypovolemia
 CVP exceeds 15 cm of water or rise > 5 cm of water – Pump Failure
 Pulmonary artery occlusive pressure (PAOP)
 Remember - Diagnose before BP falls significantly – 25% deficit

7. Management – Hypovolemic shock
 Early recognition of shock state - Restoration of effective blood
volume suitable fluids – CVP measurement
 Whole blood and plasma
 Colloidal plasma substitutes – Dextran, hydroxyethyl starch, polyvinylpyrrolidone
etc.
 Crystalloid plasma substitutes – NaCl and 5% Dextrose
 Lactic acidosis correction - Sodium bicarbonate
 Abnormalities of electrolyte balance correction
 Correction of causative factor – haemostasis, surgical removal of
necrotic tissue, antibiotics, defibrillation etc.
 Injection Morphine for pain relieving – except head injury and acute
abdomen
 Vasopressor agents – DA (0.2 – 1 mg/min) or NA to correct
hypotension – after fluid replacement only (NA – 4 mg in 50 ml)
 Oxygen administration to correct tissue hypoxemia

8. IV Fluid
Severe hypovolemia, low/unrecordable BP,
feeble/unpalpable pulse etc. IV fluid wide open
rate (10 – 20 ml/min) for 1 hour (approx.) for
fluid replacement
 If improvement – reduce to IF fluid and continue till 24
hours
 If no improvement – Increase/Prolong the IF fluid
administration
 If no improvement – haemtocrit rise - IV Colloid 10
mg/kg/hour
 If no improvement – Blood/Plasma transfusion

9. Management - Bacteremic Shock
Endotoxic Shock: Severe infection and tissue
hypoperfusion – organ dysfunction
Antibiotics – empirical to start with
Surgical Removal if required
Blood volume expansion, correction of acidosis,
Casopressor agents, correction of hypoglycaemia
Lung protective ventilation – low tidal volumes (6
ml/kg of ideal body weight)

10. Acute Myocardial Infarction
Before hospitalization
 Sublingual Nitroglycerine 0.4 mg every 5 minutes till
pain subsides (max 3 doses)
 Relief of Pain: Morphine Injection 10 mg IV for 10
minutes together with IV Metoclpramide
 Repeat after 30 minutes if necessary – alternatively Pethidine or
Bupreonorphine (SC)
 Absolute confinement to bed - Oxygen 100% by face mask
 Antiplatelet therapy – 80 to 160 mg Aspirin to be chewed

11. AMI – after hospitalization
 Bed Rest
 Maintenance of blood volume and tissue perfusion – elevated lower limbs and IV
fluid 5% Dextrose – CVP or PAOP
 Treatment of hypotension (to decrease preload and increase CO) – IV inotropic
drugs – Dopamine or Dobutamine or IV furosemide
 Correction of acidosis – sod. Bicarbonate infusion
 Prevention of arrhythmia – IV Beta blockers – Propranolol (0.1 mg/kg in 3 divided
doses at 5-10 minutes interval followed by orally every 6 hourly) … .
Tachyarrhythmia (IV Lignocaine – 1 – 2 mg/minute IV or Procainamide)
 Continue IV Vasodilators (GTN) or Nitroprusside
 Thrombolytic Therapy – continue with Aspirin and start Streptokinase or
Urokinase or Alteplase (rt-PA) or tenecteplase … 2.5 lac IU IV over 10 minutes
followed by 5 Lac IU over next 60 minutes …. 100 mg for 1 hr 15 mg – 50 mg – 15
mg … PCI (stent implantation)
 Prevention of remodeling and future attacks – ACEIs or ARBs Platelet inhibitors

12. Anaphylactic shock Management
 Lay the patient flat and raise legs
 Torniquet if possible to obstruct draining blood flow from the site of
antigen deposition
 Airway maintenance
 Adrenaline Injection (1:1000) IM – 0.5 ml slowly - if severely ill give IV
adrenaline (1:10,000) 3-5 ml slowly … can be repeated after 15-20 minutes
(Beta blocker ?)
 IF fluid – large fluid amount – colloids – with Dopamine or NA
 Corticosteroids – IV Hydrocortisone 100 mg follwed by prednisolone
 Antihistaminics: Chlorpheniramine 10 – 20 mg slow IV over 1 minute – can
be repeated
 Bronchodilators – aminophylline IV or nebulized salbutamol
 Supportive measure – Oxygen and assisted ventilation

13. Other types of Shocks
Neurogenic shock: Treated like hypovolemic shock
with use of vasopressor agents
Haemo-obstructive shock – Like cardiogenic shock

14. Case Study - Example
 First Aid Staff initiated transport of a 25-year-old female who cut both of
her wrists in an apparent suicide attempt. On arrival of the First Aid Staff
at the scene, the patient was awake, but drowsy, with active bleeding
from both wrists. The field team estimates a 900-ml blood loss on scene.
The bleeding is now controlled with direct pressure, and a large-bore IV
catheters have been established. The patient’s present systolic blood
pressure is 60 mm Hg. Normal saline IV lines are running wide open.
How do you manage the case in Hospital ???
 This patient is suffering from hypovolemic shock and requires fluid
resuscitation. In this case, the hemorrhage is controlled, and fluids
should be administered at a wide open rate with pressure applied to the
IV fluid bag to increase the flow. Unlike the uncontrolled hemorrhage
model in which aggressive fluid administration may lead to increased
bleeding, the bleeding here is controlled. Therefore, fluid volume should
be rapidly replaced to normalize blood pressure

15. Thank you – Khublei shibun