What is septic shock?
Septic shock is a serious medical condition that occurs when sepsis leads to dangerously low blood pressure and abnormalities in cellular metabolism. Sepsis is a systemic inflammatory response to infection that can damage multiple organ systems. When sepsis causes blood pressure to drop to dangerously low levels, depriving vital organs of oxygen and nutrients, it progresses to septic shock. Septic shock has a high risk of mortality and requires rapid medical intervention to stabilize blood pressure, treat the underlying infection, and support failing organs.
What causes septic shock?
Septic shock is caused by an uncontrolled systemic infection leading to sepsis. Any type of infection can potentially progress to septic shock if left untreated, but common culprits include:
- Bacterial infections: Bacteria are the most common cause of sepsis and septic shock. Common sources include urinary tract infections, pneumonia, intra-abdominal infections, meningitis, and infected wounds.
- Viral infections: Viruses like influenza, HIV, hepatitis, herpes simplex can also trigger sepsis and septic shock in some cases.
- Fungal infections: Invasive fungal infections are an increasingly recognized cause of sepsis, especially in immunocompromised patients.
- Parasitic infections: Malaria, trypanosomiasis and other parasitic infections account for many cases of septic shock worldwide.
Any infection that enters the bloodstream (bacteremia) or spreads systemically can lead to septic shock. Severe, untreated infections allow microbes and their toxins to circulate through the blood, causing widespread inflammation and damage. Patients who are immunocompromised are at higher risk of their infections progressing to sepsis.
What are the signs and symptoms of septic shock?
Septic shock can develop quickly and lead to serious symptoms within hours. Potential signs and symptoms include:
- Fever above 101°F (38°C) or below 96.8°F (36°C)
- Heart rate higher than 90 beats per minute
- Respiratory rate higher than 20 breaths per minute
- Altered mental status, such as confusion or disorientation
- Low blood pressure that continues to drop
- Organ dysfunction symptoms like kidney failure, acute respiratory distress syndrome, or signs of tissue hypoxia
- Skin changes like mottling or discoloration
- Low urine output
In the early stages of septic shock, the body attempts to compensate for falling blood pressure by increasing heart rate and constricting blood vessels. This leads to the hallmark symptoms of high heart rate, high respiratory rate, and confusion. As shock progresses and decompensation occurs, blood pressure continues to drop critically low despite interventions. This can quickly lead to organ failure and death without prompt treatment.
Who is at risk for septic shock?
While septic shock can occur in anyone with a severe infection, certain groups are at higher risk:
- Infants and young children
- Older adults over the age of 65
- People with chronic illnesses like diabetes, cancer, kidney disease, HIV
- Patients taking immunosuppressive drugs
- Patients with indwelling catheters or who are on dialysis or mechanical ventilation
- People with alcohol use disorder or injection drug use
- Post-operative and trauma patients
- Pregnant women
Those with weakened immune systems from age, illness or medications are less able to fend off infections before they progress to severe sepsis. However, septic shock can also occur in previously healthy people with severe infections. Quick recognition and treatment in high risk groups improves outcomes.
How is septic shock diagnosed?
Septic shock is diagnosed based on clinical presentation, alongside tests to identify infection and organ dysfunction:
- Clinical signs: Doctors diagnose septic shock in patients with suspected or confirmed infection who have signs of dysfunction in at least one organ system due to sepsis. Blood pressure is below 90/60 mm Hg and does not improve with intravenous fluid resuscitation.
- Labs: Results may show elevated white blood cell count, high lactate, abnormal liver enzymes, kidney dysfunction, coagulation abnormalities. Positive blood cultures help identify the source.
- Imaging: Chest X-ray, CT scans, ultrasounds detect sources of infection like pneumonia, pyelonephritis, infected wounds.
- Cultures: Blood, urine, sputum, wound cultures help isolate the infectious agent for identification and antibiotic susceptibility testing.
Hypoperfusion and shock are evident on labs through elevated lactate levels, mixed venous oxygen saturation, and abnormalities in coagulation. Rapid diagnosis is critical to initiate needed interventions.
How is septic shock treated?
Treating septic shock focuses on early, aggressive resuscitation to improve tissue perfusion along with controlling the source of infection:
Hemodynamic resuscitation
- Intravenous fluids: Large volumes are given to improve blood pressure and tissue perfusion. 30 ml/kg within 3 hours is standard.
- Vasopressors: Medications like norepinephrine tighten blood vessels to increase blood pressure.
- Dobutamine or epinephrine: Used to raise cardiac output in some cases.
- Corticosteroids: Help reverse shock and reduce inflammation in most patients.
Infection source control
- Broad spectrum antibiotics: Started immediately to treat suspected infection before culture results return.
- Surgery: Required if infection source is drained, debrided or removed, like an abscess or infected pancreas.
- Antivirals/antifungals: Added if cultures grow viruses or fungus.
Organ support
- Mechanical ventilation: Provides oxygenation support in respiratory failure.
- Renal replacement therapy: Treats acute kidney injury or multi-organ failure.
Additional care like transfusion of blood products, nutrition, glucose control, and preventing complications like blood clots or gastrointestinal bleeds improves outcomes.
When should you go to the emergency room for septic shock?
Septic shock is a medical emergency requiring hospitalization in the intensive care unit. You should go to the emergency room right away if you or a loved one shows any of the following:
- Confusion, disorientation, or delirium
- High fever and chills
- Difficulty breathing or rapid breathing
- Skin that is cold, clammy, mottled, or purplish
- Severe pain or discomfort
- Low blood pressure or dizziness upon standing
- Little or no urine output
Do not wait for other symptoms to develop. Septic shock requires early detection and immediate medical intervention to minimize organ damage and save lives. Call emergency services or go directly to your nearest ER if sepsis is suspected. Every hour that treatment is delayed increases mortality risk.
What is the prognosis and mortality rate for septic shock?
Despite improvements in care, septic shock still carries high risk of mortality and complications:
- Mortality rate remains around 40% overall.
- Higher mortality of 50-60% is seen in elderly patients over 85 years old.
- Each hour delay in treatment is associated with a 4-8% increase in mortality risk.
- About 50% of septic shock survivors experience long-term impacts like physical disability, cognitive decline, and reduced quality of life.
Early recognition, prompt administration of antibiotics, and aggressive resuscitation are key to improving chances of survival. Patients who develop multi-organ failure and those with multiple comorbidities have worse prognosis. Access to high quality critical care also significantly improves outcomes.
Table: Septic Shock Mortality Rate by Age
| Age Range | Mortality Rate |
|---|---|
| 18-44 years old | 25% |
| 45-64 years old | 33% |
| 65-84 years old | 40% |
| Over 85 years old | 50-60% |
How can septic shock be prevented?
While not every case can be avoided, important preventive measures include:
- Get recommended vaccines like flu, pneumonia, meningitis to prevent infections.
- Practice good hygiene and handwashing to prevent spread of pathogens.
- Manage chronic conditions like diabetes to reduce infection risk.
- Get preventive antibiotics before surgery if at high infection risk.
- Use antibiotics correctly without overusing or misusing them.
- Promptly treat any infections before they spread.
- Get early medical care for infections during pregnancy.
- Avoid indwelling catheters when possible.
Hospitals and long term care facilities should have infection control programs to prevent spread between patients and reduce sepsis incidence. Public awareness campaigns help people recognize sepsis symptoms early. Priority research efforts into diagnostics, new treatments and prevention strategies will also help reduce septic shock cases.
Conclusion
Septic shock is a life-threatening condition resulting from uncontrolled infection leading to dangerous blood pressure changes, organ damage and death. Progression to septic shock can be rapid, so early recognition of sepsis and prompt emergency treatment are critical. Resuscitation to improve perfusion along with antibiotics and source control help reduce the nearly 40% mortality rate. Increased public awareness, preventive measures and improved therapies continue to advance the ability to stabilize patients and save lives from septic shock.
