SIRS, Sepsis, MODS Cram Sheet
1. SIRS (Systemic Inflammatory Response Syndrome)
Definition:
A systemic inflammatory response to a variety of insults, including infection, trauma, burns, or pancreatitis. Not always infectious.
Diagnostic Criteria (Need 2 or more):
Mnemonic: TEMP-HR-RR-WBC
Parameter | SIRS Criteria | Tip to Remember |
Temperature | >38°C or <36°C | Hot or cold fever |
Heart Rate | >90 bpm | Tachycardia warning |
Respiratory Rate | >20/min or PaCO₂ <32 mmHg | Fast or hyperventilating |
WBC | >12,000 or <4,000 or >10% bands | White cells high/low or immature cells |
Key Points:
SIRS can be infectious or non-infectious
Early recognition is crucial
Can progress to Sepsis → Severe Sepsis → Septic Shock → MODS
2. Sepsis
Definition: Life-threatening organ dysfunction caused by a dysregulated host response to infection.
Key Features:
Infection + SIRS
Evidence of organ dysfunction (labs, vitals, clinical signs)
Organ Dysfunction Signs:
Mnemonic: LUNG-H
Organ | Sign |
Lungs | PaO₂/FiO₂ <300 (hypoxemia) |
Urine | <0.5 mL/kg/hr (oliguria) |
Neurologic | GCS <15, confusion |
Gastrointestinal | ileus, high bilirubin |
Heart | hypotension, high lactate |
Labs:
Lactate >2 mmol/L → poor perfusion
WBC high or low
Platelets low (thrombocytopenia)
Creatinine ↑ → kidney dysfunction
Treatment:
Early recognition → most important
IV fluids → 30 mL/kg crystalloid bolus
Broad-spectrum antibiotics → within 1 hour
Source control → drain abscess, remove lines
Vasopressors if MAP <65 mmHg (e.g., norepinephrine)
3. MODS (Multiple Organ Dysfunction Syndrome)
Definition: Progressive organ dysfunction in acutely ill patients, often after sepsis.
Pathophysiology:
Uncontrolled inflammation → tissue damage → organ failure
Microvascular thrombosis → ischemia → multi-organ failure
Common Organ Failures:
Mnemonic: HUNK-L
Organ | Dysfunction |
Heart | Low BP, arrhythmias |
Urinary | Acute kidney injury, low urine |
Neuro | Confusion, delirium, coma |
Lungs | ARDS, low oxygen |
Kidneys | Oliguria/anuria |
Liver | Jaundice, high bilirubin |
Hematologic | DIC, low platelets, bleeding |
Key Points:
Early recognition is critical
Supportive care: ventilation, dialysis, nutrition, infection control
High mortality if untreated
Quick Mnemonics for Remembering Progression
SIRS → Sepsis → Severe Sepsis → Septic Shock → MODS
Sepsis Signs: TEMP-HR-RR-WBC + organ dysfunction (LUNG-H)
MODS Organs: HUNK-L (Heart, Urine, Neuro, Lungs, Kidneys, Liver, Hematologic)
Quick Nursing Cheat Tips
Monitor vitals q1-2h: early tachycardia, hypotension, tachypnea
Assess urine output: <0.5 mL/kg/hr is red flag
Check labs: lactate, WBC, platelets, creatinine, bilirubin
Early IV antibiotics within 1 hour of recognition
Fluid resuscitation: 30 mL/kg crystalloid bolus for hypotension
Watch for organ failure: lungs (O₂), kidneys (UOP), liver (bilirubin), brain (GCS)