9. Low Blood Flow
Hypovolemic Shock
Absolute hypovolemia: Loss of intravascular fluid
volume
Hemorrhage
GI loss (e.g., vomiting, diarrhea)
Fistula drainage
Diabetes insipidus
Hyperglycemia
Diuresis
10. Low Blood Flow
Hypovolemic Shock (Cont’d)
Relative hypovolemia
Results when fluid volume moves out of the vascular
space into extravascular space (e.g., interstitial or
intracavitary space)
Termed third spacing
12. Low Blood Flow
Hypovolemic Shock
Response to acute volume loss depends on
Extent of injury or insult
Age
General state of health
13. Low Blood Flow
Hypovolemic Shock (Cont’d)
Clinical manifestations
Anxiety
Tachypnea
Increase in CO, heart rate
Decrease in stroke volume, PAWP, UO
If loss is >30%, blood volume is replaced
14. Maldistribution of Blood Flow
Neurogenic Shock
Hemodynamic phenomenon that can occur within 30
minutes of a spinal cord injury at the fifth thoracic
(T5) vertebra or above and can last up to 6 weeks
Results in massive vasodilation leading to pooling of
blood in vessels
16. Maldistribution of Blood Flow
Neurogenic Shock (Cont’d)
Clinical manifestations
Hypotension
Bradycardia
Temperature dysregulation (resulting in heat loss)
Dry skin
Poikilothermia (taking on the temperature of the
environment)
18. Maldistribution of Blood Flow
Anaphylactic Shock (Cont’d)
Clinical manifestations
Anxiety, confusion, dizziness
Tachycardia, tachypnea, hypotension
Wheezing, stridor
Sense of impending doom
Chest pain
19. Maldistribution of Blood Flow
Anaphylactic Shock (Cont’d)
Clinical manifestations
Swelling of the lips and tongue, angioedema
Wheezing, stridor
Flushing, pruritus, urticaria
Respiratory distress and circulatory failure
20. Maldistribution of Blood Flow
Septic Shock
Sepsis: Systemic inflammatory response to
documented or suspected infection
Severe sepsis = Sepsis + Organ dysfunction
21. Maldistribution of Blood Flow
Septic Shock (Cont’d)
Septic shock = Presence of sepsis with hypotension
despite fluid resuscitation + Presence of tissue
perfusion abnormalities
22. Maldistribution of Blood Flow
Septic Shock (Cont’d)
Mortality rates as high as 50%
Primary causative organisms
Gram-negative and gram-positive bacteria
Endotoxin stimulates inflammatory response
24. Maldistribution of Blood Flow
Septic Shock
Clinical manifestations
↑ Coagulation and inflammation
↓ Fibrinolysis
Formation of microthrombi
Obstruction of microvasculature
Hyperdynamic state: Increased CO and decreased SVR
25. Maldistribution of Blood Flow
Septic Shock (Cont’d)
Clinical manifestations
Tachypnea/hyperventilation
Temperature dysregulation
↓ Urine output
Altered neurologic status
GI dysfunction
Respiratory failure is common
26. Stages of Shock
Initial Stage
Usually not clinically apparent
Metabolism changes from aerobic to anaerobic
Lactic acid accumulates and must be removed by blood
and broken down by liver
Process requires unavailable O2
27. Stages of Shock
Compensatory Stage (Nonprogressive)
Clinically apparent
Neural
Hormonal
Biochemical compensatory mechanisms
Attempts are aimed at overcoming consequences of
anaerobic metabolism and maintaining homeostasis
28. Stages of Shock
Compensatory Stage (Nonprogressive)
Baroreceptors in carotid and aortic bodies activate SNS
in response to ↓ BP
Vasoconstriction while blood to vital organs maintained
↓ Blood to kidneys activates renin–angiotensin system
↑ Venous return to heart, CO, BP
30. Stages of Shock
Compensatory Stage (Nonprogressive
Cont’d)
If perfusion deficit corrected, patient recovers with no
residual sequelae
If deficit not corrected, patient enters progressive stage
31. Stages of Shock
Progressive Stage (intermediate)
Begins when compensatory mechanisms fail
Aggressive interventions to prevent multiple organ
dysfunction syndrome
33. Stages of Shock
Progressive Stage (intermediate Cont’d)
Hallmarks of ↓ cellular perfusion and altered capillary
permeability:
Leakage of protein into interstitial space
↑ Systemic interstitial edema
34. Stages of Shock
Progressive Stage (intermediate Cont’d)
Anasarca (severe generalized edema)
Fluid leakage affects solid organs and peripheral tissues
↓ Blood flow to pulmonary capillaries
35. Stages of Shock
Progressive Stage (intermediate Cont’d)
Movement of fluid from pulmonary vasculature to
interstitium
Pulmonary edema
Bronchoconstriction
↓ Residual capacity
36. Stages of Shock
Progressive Stage (intermediate Cont’d)
Fluid moves into alveoli
Edema
Decreased surfactant
Worsening V/Q mismatch
Tachypnea
Crackles
Increased work of breathing
37. Stages of Shock
Progressive Stage (intermediate Cont’d)
CO begins to fall
Decreased peripheral perfusion
Hypotension
Weak peripheral pulses
Ischemia of distal extremities
38. Stages of Shock
Progressive Stage (intermediate Cont’d)
Myocardial dysfunction results in
Dysrhythmias
Ischemia
Myocardial infarction
End result: Complete deterioration of cardiovascular system
39. Stages of Shock
Progressive Stage (intermediate Cont’d)
Mucosal barrier of GI system becomes ischemic
Ulcers
Bleeding
Risk of translocation of bacteria
Decreased ability to absorb nutrients
40. Stages of Shock
Progressive Stage (intermediate Cont’d)
Liver fails to metabolize drugs and wastes
Jaundice
Elevated enzymes
Loss of immune function
Risk for DIC and significant bleeding
44. Stages of Shock
Refractory Stage (Cont’d)
Failure of one organ system affects others
Recovery unlikely
45. Diagnostic Studies
Thorough history and physical examination
No single study to determine shock
Blood studies
Elevation of lactate
Base deficit
12-lead ECG
Chest x-ray
Hemodynamic monitoring
46. Collaborative Care
Successful management includes
Identification of patients at risk for shock
Integration of the patient’s history, physical
examination, and clinical findings to establish a
diagnosis
47. Collaborative Care (Cont’d)
Successful management includes
Interventions to control or eliminate the cause of the
decreased perfusion
Protection of target and distal organs from dysfunction
Provision of multisystem supportive care
49. Collaborative Care (Cont’d)
Cornerstone of therapy for septic, hypovolemic, and
anaphylactic shock = volume expansion
Isotonic crystalloids (e.g., normal saline) for initial
resuscitation of shock
50. Collaborative Care (Cont’d)
Volume expansion
If the patient does not respond to 2 to 3 L of crystalloids,
blood administration and central venous monitoring
may be instituted
Complications of fluid resuscitation
Hypothermia
Coagulopathy
51. Collaborative Care (Cont’d)
Primary goal of drug therapy = correction of decreased
tissue perfusion
Vasopressor drugs (e.g., epinephrine)
Achieve/maintain MAP >60 to 65 mm Hg
Reserved for patients unresponsive to other therapies
52. Collaborative Care (Cont’d)
Primary goal of drug therapy = correction of decreased
tissue perfusion
Vasodilator therapy (e.g., nitroglycerin [cardiogenic
shock], nitroprusside [noncardiogenic shock])
Achieve/maintain MAP >60 to 65 mm Hg
53. Collaborative Care (Cont’d)
Nutrition is vital to decreasing morbidity from shock
Initiate enteral nutrition within the first 24 hours
54. Collaborative Care (Cont’d)
Nutrition is vital to decreasing morbidity from shock
Initiate parenteral nutrition if enteral feedings
contraindicated or fail to meet at least 80% of the caloric
requirements
Monitor protein, nitrogen balance, BUN, glucose,
electrolytes
55. Collaborative Care
Cardiogenic Shock
Restore blood flow to the myocardium by restoring the
balance between O2 supply and demand
Thrombolytic therapy
Angioplasty with stenting
Emergency revascularization
Valve replacement
56. Collaborative Care
Cardiogenic Shock (Cont’d)
Hemodynamic monitoring
Drug therapy (e.g., diuretics to reduce preload)
Circulatory assist devices (e.g., intra-aortic balloon
pump, ventricular assist device)
57. Collaborative Care
Hypovolemic Shock
Management focuses on stopping the loss of fluid and
restoring the circulating volume
Fluid replacement is calculated using a 3:1 rule (3 ml of
isotonic crystalloid for every 1 ml of estimated blood
loss)
58. Collaborative Care
Septic Shock
Fluid replacement (e.g., 6 to 10 L of isotonic
crystalloids and 2 to 4 L of colloids) to restore
perfusion
Hemodynamic monitoring
Vasopressor drug therapy; vasopressin for patients
refractory to vasopressor therapy
59. Collaborative Care
Septic Shock (Cont’d)
Intravenous corticosteroids for patients who require
vasopressor therapy, despite fluid resuscitation, to
maintain adequate BP
60. Collaborative Care
Septic Shock (Cont’d)
Antibiotics after obtaining cultures
(e.g., blood, wound exudate, urine, stool, sputum)
Drotrecogin alfa (Xigris)
Major side effect: Bleeding
61. Collaborative Care
Septic Shock (Cont’d)
Glucose levels <150 mg/dl
Stress ulcer prophylaxis with histamine (H2)-receptor
blockers
Deep vein thrombosis prophylaxis with low-dose
unfractionated heparin or low-molecular-weight
heparin
62. Collaborative Care
Neurogenic Shock
In spinal cord injury: Spinal stability
Treatment of the hypotension and bradycardia with
vasopressors and atropine
Fluids used cautiously as hypotension is generally not
related to fluid loss
Monitor for hypothermia
63. Collaborative Care
Anaphylactic Shock
Epinephrine, diphenhydramine
Maintaining a patent airway
Nebulized bronchodilators
Endotracheal intubation or cricothyroidotomy may be
necessary
64. Collaborative Care
Anaphylactic Shock (Cont’d)
Aggressive fluid replacement
Intravenous corticosteroids if significant hypotension
persists after 1 to 2 hours of aggressive therapy
66. Nursing Assessment (Cont’d)
Brief history
Events leading to shock
Onset and duration of symptoms
Details of care received before hospitalization
Allergies
Vaccinations
67. Nursing Diagnoses
Ineffective tissue perfusion: Renal, cerebral,
cardiopulmonary, gastrointestinal, hepatic, and
peripheral
Fear
Potential complication: Organ ischemia/dysfunction
68. Planning
Goals for patient
Assurance of adequate tissue perfusion
Restoration of normal or baseline BP
Return/recovery of organ function
Avoidance of complications from prolonged states of
hypoperfusion
69. Nursing Implementation
Health Promotion
Identify patients at risk (e.g., elderly patients, those with
debilitating illnesses or who are immunocompromised,
surgical or accidental trauma patients)
70. Nursing Implementation
(Cont’d)
Health Promotion
Planning to prevent shock
(e.g., monitoring fluid balance to prevent hypovolemic
shock, maintenance of handwashing to prevent spread
of infection)
71. Nursing Implementation
(Cont’d)
Acute Interventions
Monitor the patient’s ongoing physical and emotional
status to detect subtle changes in the patient’s condition
Plan and implement nursing interventions and therapy
72. Nursing Implementation
(Cont’d)
Acute Interventions
Evaluate the patient’s response to therapy
Provide emotional support to the patient and family
Collaborate with other members of the health team
when warranted
73. Nursing Implementation
(Cont’d)
Neurologic status: Orientation and level of
consciousness
Cardiac status
Continuous ECG
VS, capillary refill
Hemodynamic parameters: central venous pressure, PA
pressures, CO, PAWP
Heart sounds: Murmurs, S3, S4
74. Nursing Implementation
(Cont’d)
Respiratory status
Respiratory rate and rhythm
Breath sounds
Continuous pulse oximetry
Arterial blood gases
Most patients will be intubated and mechanically
ventilated
76. Nursing Implementation
(Cont’d)
Nasogastric drainage/stools for occult blood
I&O, fluid and electrolyte balance
Oral care/hygiene based on O2 requirements
Passive/active range of motion
77. Nursing Implementation
(Cont’d)
Assess level of anxiety and fear
Medication PRN
Talk to patient
Visit from clergy
Family involvement
Comfort measures
Privacy
Call light within reach
78. Evaluation
Normal or baseline, ECG, BP, CVP, and PAWP
Normal temperature
Warm, dry skin
Urinary output >0.5 ml/kg/hr
Normal RR and SaO2 ≥90%
Verbalization of fears, anxiety
