Material management in nursing

1. Vasoactive agents
Dr KIRUBEL TINSAE MD
Assistant professor in Anesthesiology and critical care

2. Outlines
• What?
• When?
• Why?

3. • A 65 yrs. old male patient with esophageal ca
procedure-m esophagectomy
Vital signs- BP-7040
HR-90
SaO2-99
What is your next step?

4. • A 32 years old female, known cardiac patient for the last 11 years. came with
cardiogenic shock
• Preferred choice of vasoactive agent is……?

5. Definitions
• Pressor: Increases blood pressure by stimulating constriction of blood
vessels
• Increases vascular tone
• Inotrope: Alters force or energy of muscular contractions
• Positive: Increases myocardial contractility
• Chronotropic-increase heart rate

6. The autonomic nervous system
• Responsible for maintaining normal functions such as
• blood pressure and blood flow.
• It has two divisions;
• the parasympathetic and the sympathetic systems.
• The parasympathetic
• conservation of energy and maintenance of organ function during periods of minimal
activity,
• The sympathetic acts when the ‘fight or flight’ response is required.

7. • The parasympathetic nervous system
• to regulation of heart function through the vagus nerve where it slows the rate
• has little or no control over the blood vessels.
• The sympathetic nervous system
• An excitatory influence on heart rate and contractility and
• controls the smooth muscle tone of the blood vessels.
• The increases in sympathetic activity will increase the constriction or visa versa.

8. • The main types of adrenergic receptors are
• alpha (α), beta (β) and dopamine (DA),
• Generally, α receptors cause constriction, while β cause dilation and increased
contractility.
• Some blood vessels are supplied with both these constrictor and dilator
receptors.

9. • An adrenergic agonist is a drug that stimulates a response from the adrenergic
receptors.
• Inotropes are agents that increase myocardial contractility (inotropy)
• e.g. adrenaline, dobutamine, dopamine.
• Vasopressors are agents that cause vasoconstriction leading to increased systemic and/or
pulmonary vascular resistance (SVR, PVR)
• e.g. noradrenaline, metaraminol.
• Inodilators are agents with inotropic effects that also cause vasodilation leading to decreased
SVR and/or PVR e.g. dobutamine.

10. • 1 heart and 2 lungs’ refers to
• α1 and β1 being found in the heart,
• α2 and β2 will be found in the lungs
• α1 and β2 will be found in blood vessels

11. Type Tissue Actions
Alpha 1 (α1)
Most vascular smooth muscle Constriction
Heart Increased force of constriction (inotropy)
Alpha 2(α2) Vascular adreneric nerve terminals
Inhibition of sympathetic activity. Has central
and peripheral effects – BP ↑ or ↓
Beta 1(β1) Heart
Increased rate (chronotropy) and force of
contraction
Beta 2(β2)
Bronchi, uterine and vascular
smooth muscle
Relaxation – causes dilation
Beta 3(β3) Heart
Increased force of contraction in healthy heart
Cardioprotective in heart failure – has negative
inotropic effect
Dopamine (DA1)
Vascular bed of brain, splanchnic
organs<, kidneys and coronary
arteries
Increases peripheral resistance (vasoconstriction)
but can vasodilate renal and gut circulation. Can
also increase vascular resistance systemically

12. Receptor Alpha 1 Beta 1 Beta 2 DA1
Metaraminol +++ + 0 0
Adrenaline (epinephrine) +/++ ++ + 0
Noradrenaline (norepinephrine) +++ +++ + 0
Phenylephrine ++ 0 0 0
Dobutamine + ++ +/++ 0
Dopamine ++ + 0 +++
Dopexamine 0 + +++ ++
Ephedrine ++ ++ 0 0

14. Shock
• Inability of oxygen delivery to meet tissue oxygen requirements
• Hypovolemia (decreased circulating volume)
• Cardiac function impairment (decreased myocardial contractility)
• Inappropriate distribution of cardiac output secondary to abnormal vasodilatation

15. • Cardiac output
• Heart Rate
• Sympathetic and Parasympathetic tone
• Circulating chatecolamines
• Preload
• Changes in venous return
• Changes in plasma volume
• Contractility
• Sympathetic tone
• Circulating catecholamines

16. Septic shock
• Hypotension despite adequate fluid resuscitation
• Presence of hypoperfusion or organ dysfunction
• Acidosis / alteration in mental status
• Sepsis: temp >38°C or <36°C; HR> 90 bpm*
respiratory rate>20 breaths/min, need for mechanical ventilation; WBC 12,000*

17. Cardiogenic shock
• Pump failure
• Results when more than 40% of myocardium damaged
• Similar circulatory and metabolic changes to hemorrhagic shock

18. Treatment
1. Fluids / Procedures
2. DRUGS!
• Vasopressors
• Inotropes

19. Vasopressor
• Norepinephrine
• 0.01mcg/kg/min-3mcg/kg/min
• Dopamine
• 5-10 mcg/kg/min-Renal Dose
• 10-20mcg/kg/min-cardiac dose
• 20-40 mcg /kg/min :vascular dose
• Epinephrine
• 0.01mcg/kg/min -1mcg/kg/min
• Vasopressin
• 10IU-40 IU
• Phenylephrine
• 0.15-1mcg/kg/min

20. Phenylephrine
• Selective α1-adrenergic agonist
• Rapid onset
• Short duration
• Primary vascular effects
• Second line in septic shock
Indicated in other distributive shock
• Spinal shock
• Medication induced hypotension

21. Summary
• Perfusion adequacy is important!!!
• Restore effective tissue perfusion (In all organs) and normalize cellular metabolism