MODS- Multiple Organ Dysfunction Syndrome & SIRS - Systemic Inflammatory Response Syndrome Notes

Question 1

Systemic inflammatory response syndrome (SIRS)

Answer 1

Systemic inflammatory response to a variety of insults, including infection (referred to as sepsis), ischemia, infarction, and injury.

Question 2

Mechanisms that can trigger SIRS

Answer 2

• Mechanical tissue trauma: burns, crush injuries, surgical procedures
• Abscess formation: intraabdominal, extremities
• Ischemic or necrotic tissue: pancreatitis, vascular disease, MI
• Microbial invasion: bacteria, viruses, fungi, parasites
• Endotoxin release: gram-negative and gram-positive bacteria
• Global perfusion deficits: postcardiac resuscitation, shock states
• Regional perfusion deficits: distal perfusion deficits

Question 3

Multiple organ dysfunction syndrome (MODS)

Answer 3

failure of 2 or more organ systems in an acutely ill patient such that homeostasis cannot be maintained without intervention

Question 4

Respiratory System Manifestations

Answer 4

ARDS
• Bilateral fluffy infiltrates on chest x-ray
• Decreased compliance
• Dyspnea (severe)
• Increased minute ventilation
• PaO2/FIO2 ratio <200
• PAWP <18 mm Hg
• Pulmonary hypertension
• Refractory hypoxemia
• Tachypnea
• Ventilation-perfusion (V/Q) mismatch

Question 5

Respiratory System Management

Answer 5

Optimize O2 delivery and minimize O2 consumption
Mechanical ventilation
• Positive end-expiratory pressure
• Lung protective modes (e.g., pressure-control inverse ratio ventilation, low tidal volumes)
• Permissive hypercapnia
• Positioning (e.g., continuous lateral rotation therapy, prone positioning)

Question 6

Cardiovascular System Manifestations

Answer 6

Biventricular failure
↓ BP, MAP, SVR
↑ HR, CO, SV
Massive vasodilation
Myocardial depression
Systolic, diastolic dysfunction

Question 7

Cardiovascular System Management

Answer 7

Volume management to ↑ preload
Hemodynamic monitoring
Arterial pressure monitoring to maintain MAP >65 mm Hg
Vasopressors
Intermittent or continuous ScvO2 or SvO2 monitoring
Balance O2 supply and demand
Continuous ECG monitoring
Circulatory assist devices
VTE prophylaxis

Question 8

CNS Manifestations

Answer 8

Acute change in neurologic status
Confusion, disorientation, delirium
Fever
Hepatic encephalopathy
Seizures

Question 9

CNS Management

Answer 9

Evaluate for hepatic or metabolic encephalopathy
Optimize cerebral blood flow
↓ Cerebral O2 requirements
Prevent secondary tissue ischemia
Calcium channel blockers (reduce cerebral vasospasm)

Question 10

Endocrine System Manifestations

Answer 10

Hyperglycemia → hypoglycemia

Question 11

Endocrine System Management

Answer 11

Provide continuous infusion of insulin and glucose to maintain blood glucose 140–180 mg/dL (7.77–10.0 mmol/L)

Question 12

Renal System: prerenal Manifestations

Answer 12

Prerenal: renal hypoperfusion
• BUN/creatinine ratio >20:1
• ↓ Urine Na+ <20 mEq/L
• ↑ Urine osmolality
• Urine specific gravity >1.020

Question 13

Renal System: prerenal Management

Answer 13

Diuretics
• Loop diuretics (e.g., furosemide [Lasix])
• May need to ↑ dosage due to ↓ glomerular filtration rate

Question 14

Renal System: intrarenal manifestations

Answer 14

Intrarenal: acute tubular necrosis
• BUN/creatinine ratio <10:1–15:1
• ↑ Urine Na+ >20 mEq/L
• ↓ Urine osmolality
• Urine specific gravity ∼1.010

Question 15

Renal System: intrarenal management

Answer 15

Continuous renal replacement therapy

Question 16

GI manifestations

Answer 16

GI bleeding
Hypoperfusion → ↓ peristalsis, paralytic ileus
Mucosal ischemia
• ↓ Intramucosal pH
• Potential translocation of gut bacteria
• Potential abdominal compartment syndrome
Mucosal ulceration on endoscopy

Question 17

GI Management

Answer 17

Stress ulcer prophylaxis

• Antacids (e.g., Maalox)
• Proton pump inhibitors (e.g., omeprazole [Prilosec])
• sucralfate (Carafate)
Monitor abdominal distention, intraabdominal pressures
Dietitian consult
Enteral nutrition
Stimulate mucosal activity
Provide essential nutrients and optimal calories

Question 18

Hepatic System Manifestations

Answer 18

Bilirubin >2 mg/dL (34 μmol/L)
Hepatic encephalopathy
Jaundice
↑ Liver enzymes (ALT, AST, GGT)
↓ Serum albumin, prealbumin, transferrin
↑ Serum NH3 (ammonia)

Question 19

Hepatic System Management

Answer 19

Maintain adequate tissue perfusion
Provide nutritional support (e.g., enteral nutrition)
Careful use of drugs metabolized by liver

Question 20

Hematologic System Manifestations

Answer 20

↑ Bleeding times, ↑ PT, ↑ PTT
↑ D-dimer
↑ Fibrin split products
↓ Platelet count (thrombocytopenia)

Question 21

Hematologic System Management

Answer 21

Observe for bleeding from obvious and/or occult sites
Replace factors being lost (e.g., platelets)
Minimize traumatic interventions (e.g., IM injections, multiple venipunctures)