What is shock.
Shock is a widespread abnormal cellular metabolism that occurs when the human need for oxygenation and tissue perfusion is not met to the level needed to maintain cell function.
Hypovolemic shock
- Hypovolemic – occurs when too little circulating blood volume causes a sustained MAP decrease, resulting in the body’s total need for O2 not being met
Causes of hypovolemic shock
Hemorrhage – trauma, GI ulcers, surgery, clotting disorders
• Dehydration – vomiting, diarrhea, diaphoresis, diuretics, NG suction, diabetes insipidus (kidneys unable to conserve water), Hyperglycemia
Cardiogenic shock
- Cardiogenic – Direct pump failure (heart itself is compromised) fluid volume not affected
• MI (most common), valvular problems (stenosis, incompetence), cardiomyopathy, dysrhythmias, cardiac arrest
Distributive shock
Distributive – blood volume is not lost but is distributed to the interstitial tissues where it cannot circulate and deliver O2
Causes of distributive shock
- neural-induced loss of vascular tone
- Pain, anesthesia, stress, spinal cord injury, head trauma
- chemical-induced loss of vascular tone
- Sepsis, anaphylaxis, capillary leak (burns, trauma, liver disease)
Obstructive shock
Obstructive – Indirect pump failure (conditions outside the heart prevent either adequate filling or adequate contraction of the muscle)
- pericarditis, cardiac tamponade, pulmonary hypertension / embolism
- some of these listed above cause compression of the heart
First stage of shock
Initial (early) stage – decrease in MAP of 5-10 mm Hg
• increased sympathetic stimulation
o ↑ RR, ↑ HR, ↑ diastolic BP (from vasoconstriction)
o anxiety or restlessness THESE ARE RED FLAGS & KEY INDICATORS
o Difficult to detect because vital organ function is not disrupted
Second stage of shock
- Nonprogressive (compensatory) stage – decrease in MAP of 10-15 mm Hg from baseline
• Kidney & hormonal mechanisms are activated to aid cardiovascular system to maintain MAP
• acid-base & electrolyte changes occur (↓ pH, ↑ K+)
• continued sympathetic stimulation
o moderate vasoconstriction, ↑ HR, ↓ Pulse pressure (difference between systolic & diastolic), falling systolic, rising diastolic
o ↓ urine production, slow cap refill, cool skin
o ↑ thirst and anxiety
Third stage of shock
- Progressive stage – decrease in MAP of > 20 mm Hg from baseline
• systems starting to fail
• anoxia of nonvital organs
• hypoxia of vital organs
• pale / mottled / cyanotic skin, decreased LOC, little urine output, low central venous pressure
Fourth stage of shock
- Refractory (irreversible) stage – organs are failing (MODS – multiple organ dysfunction syndrome) Lots of tissue death and organ damage
• cyanotic, cold skin, diminished / absent pulses, unconsciousness, no urine output, significant hypotension
• Death soon follows
Neuro status change in shock
A.neurological status
• EARLY: Anxiety, Restlessness, Increased thirst
• LATE: ↓ central nervous system activity (lethargy to coma), generalized muscle weakness, diminished / absent DTR’s, Sluggish papillary response to light
Cardio change in shock
B.cardiovascular status
• ↓ cardiac output, BP
• ↑ Pulse rate (thread)
• postural hypotension, low central venous pressure
• slow cap. refill, diminished peripheral pulses
Respiratory changes in shock
C.respiratory status
• ↑ RR (shallow)
• ↓ Paco2 and Pao2
• cyanosis (especially around lips and nail beds)
Renal status
D.renal status
• ↓ urine output, ↑ specific gravity, sugar & acetone present in urine
General status during shock
E.general status (skin, temperature, and thirst)
• skin is cool to cold; pale to mottled to cyanotic; moist, clammy
• dry mouth, pastelike
• ↓ GI motility
• diminished or absent bowel sounds
• nausea, vomiting, constipation
Progression of events leading to Septic shock:
Local shock → Systemic infection (early sepsis) → SIRS (systemic inflammatory response syndrome) → organ failure (severe sepsis) → multiple organ system failure (MODS) (septic shock) → DEATH
Discuss nursing interventions indicated in hypovolemic and septic shock.
- Monitor for early compensatory shock responses (normal BP, narrowed pulse pressure, mild orthostatic hypotension, slight delayed cap. refill, pale/cool skin or flushed skin, slight tachypnea, N & V, increased thirst, weakness)
- Monitor sources of fluid loss
- Monitor for signs of inadequate tissue oxygenation (apprehension, increased anxiety, changes in mental status, agitation, oliguria, cool & mottled extremities)
- Monitor O2 sats
- O2 administration, Administer IV fluids and/or blood products, monitor vitals and note changes, assess pain levels frequently
- Use of aseptic technique during invasive procedures, removing indwelling caths and IV ASAP when no longer needed.
- Review lab values for changes in serum lactate levels, total WBC count, and in the differential.
