Septic shock {Phase A Written}

Septic shock:

Definition

It may be defined as a shock that is associated with sepsis or infection by microbes resulting in release of bacterial endotoxin and the activation of cellular and humeral components of immune system.

Causes:

1.     Surgical causes-

a.      Bowel preparation and peritonitis

b.     Strangulated intestine

c.      Soft tissue infection, abscess, gangrene

d.     Suppurative biliary condition e.g. empyema of Gall bladder

e.      Major trauma, burn etc.

f.       Gas gangrene

g.     Following operation of large gut

2.     Non-surgical causes

a.      Pneumonia

b.     Endocarditis

c.      Meningitis

d.     Hospital infection

e.      Dermatological infection

Causative organism:

1.     Gram Positive: staphylococcus, streptococcus, pneumococcus, clostridium perfringes

2.     Gram negative: E.coli, Proteus, salmonella, Klebsiella, Bacteroids

3.     Some fungi.

Types of septic shock:

   A.   Early septic shock/early warm shock/hyper dynamic stage

   B.    Late septic shock/late cold shock/hypo dynamic stage

Patho-physiology of septic shock: 

    A .   Early septic/ early warm shock/hyper dynamic stage

                     Release of endotoxin + exotoxin

                                           

Acts on plasma proteas, macrophage, endothelial cells, neutrophils

                                              

Rlease chemical mediators (cytokine IL1,2,6,8, NO, TNF, PAF, PG, LT C5a)

                                                         

                             Vasodialation( reduced systemic vascular resistance)

                                                     

                                       Hyperdynamic stage

   B.    Late septic shock/late cold shock/hypo dynamic stage:
      Delayed improper or maltreatment of early septic shock

   

                              Delayed action of endotoxin

                                                   

                             Increased vascular permeability

                                                    

                   Loss of fluid from the vascular compartment

                                                   

                                          Hypovolemia

                                                   

                                      Reduced cardiac output

                                                    

                                       Hypodynamic stage

Clinical features:

1.     Early-

a.      Patient is pink and well perfused

b.     Increased JVP

c.      Intermittent sike of fever

d.     Reduction of urine output

e.      Increased pulse rate

f.       Decreased blood pressure

g.     Mental status stable

2.     Late-

a.      Cold clammy skin

b.     Reduced JVP

c.      Reduction of urine output

d.     Increased urine output

e.      Hypotension

f.       Anxiety, restlessness, confusion

Investigation:

1.     Laboratory study: CBC, Coagulation profile, Blood biochemistry, RBS, S. electrolytes, urea, creatinine, lactate, pro calcitonin, LFT

2.     Microbiological study: Culture and sensitivity

3.     Imaging: Chest X ray, USG, CT, MRI

4.     CSF analysis

Treatment of septic shock:

1.     Immediate resuscitation:

                                                             i.      Maintenance of airway- oropharyngeal suction

                                                           ii.      Maintenance of breathing

                                                        iii.      Maintenance of circulation

                                                         iv.      Vlood sent for C/S

                                                           v.      Broad spectrum antibiotic

                                                         vi.      Anti ulcerant

                                                      vii.      Steroid – dexamethasone 1.5 mg/Kg, usefull if given within 4 hours, repeat after 4 hours

                                                   viii.      Dopamine, dobutamine, isoprenaline, vaopressin may be needed

                                                         ix.      Cathetarization to asses renal function

                                                           x.      If DIC develops

1.     Check fibrinogen level

2.     FFP transfusion

3.     Inj Heparin 100 u/Kg bullous followed by 10 u/Kg hourly,

4.     If bleeding does not stop or platelet count >40,000/mm³- platelet transfusion.

2.     Specific measures:

a.      Debridement of all dead and gangrenous tissue and proper drainage of pus

b.     If any source of infection amenable to surgery, should be treated as early as possible.

3.     Monitoring:

a.      Minimum

                                                             i.      Pulse oximetry

                                                           ii.      Blood pressure

                                                        iii.      ECG

                                                         iv.      Urine output

b.     Additional modalities:

                                                             i.      Invasive blood pressure

                                                           ii.      Central venous pressure

                                                        iii.      Cardiac output

                                                         iv.      Based deficit and serum lactate

Complication of septic shock:

                   SIRS  MODS      Death

Conclusion:

Prevention of septic shock is vital as outcome of treatment is not satisfactory and complications are devastating.