Pathophysiology & Risk Factors

Sepsis is life-threatening organ dysfunction from a dysregulated host response to infection. Vitals alone are nonspecific — abnormal screening criteria only point to sepsis when paired with a suspected or confirmed infection source. Untreated, it progresses from systemic inflammation to organ dysfunction to fluid-refractory, vasopressor-dependent septic shock.

Sepsis progression

Infectionsuspected or confirmed source
Systemic inflammationSIRS criteria, qSOFA screen
Organ dysfunctionconfusion, hypotension, rising lactate
Septic shockMAP <65 + lactate ≥4 despite fluids

Signs & Symptoms

EarlyProgresses →

warm flushed skin Hallmark

vasodilation of warm shock — NOT the cold presentation students expect

bounding pulses

tachycardia

often unexplained; HR >90

new confusion

may be the only sign in older adults

tachypnea

RR >20

low-grade or absent fever

elderly may be hypothermic instead

Late / Severe

oliguria

<0.5 mL/kg/hr; end-organ hypoperfusion

cold mottled skin

late septic shock

refractory hypotension

Diagnostics & Labs

Diagnostic

serum lactate

>2 mmol/L marks hypoperfusion; remeasure in 2–4 hr to trend clearance

blood cultures from two sites

draw BEFORE antibiotics — but never delay antibiotics to obtain them

qSOFA score

RR ≥22, GCS <15, SBP ≤100; ≥2 triggers escalation — screening tool, not a diagnosis

SIRS criteria

temp >38°C or <36°C, HR >90, RR >20, WBC >12,000 or <4,000; low specificity

Monitor

mean arterial pressure

perfusion target ≥65 mmHg

urine output

≥0.5 mL/kg/hr signals adequate perfusion

Interventions & Priorities

document time zero

exact time of sepsis recognition — Hour-1 clock starts here

draw serum lactate

obtain blood cultures

before antibiotics, without delaying them

administer broad-spectrum antibiotics

each hour of delay raises mortality

30 mL/kg crystalloid bolus

for hypotension or lactate ≥4 mmol/L; begin within the hour

start vasopressors

if MAP <65 mmHg during or after fluids

reassess perfusion markers

MAP, urine output, capillary refill, mentation, repeat lactate

Treatments & Medications

broad-spectrum IV antibiotics

empiric; antipseudomonal coverage in neutropenic sepsis

normal saline

first-line crystalloid

lactated Ringer's

first-line crystalloid

norepinephrine

first-line vasopressor for MAP <65 after fluids

Patient Teaching

report fever after infection

watch for new confusion

early sepsis sign, especially in older family members

complete antibiotic course

seek care for rapid decline

Complications

septic shock

vasopressor-dependent hypotension + lactate ≥4 despite 30 mL/kg fluids

multi-organ dysfunction

tissue hypoperfusion

death

kills more hospitalized patients than MI or stroke

Report Nowescalate immediately

MAP below 65 mmHgMAP < 65 mmHg

hypotension despite fluids — needs vasopressors

lactate 4 mmol/L or higherlactate ≥ 4 mmol/L

severe tissue hypoperfusion

rising or static lactate

current resuscitation is failing

new altered mental status

organ dysfunction in an infected client

fluid-refractory hypotension

septic shock — escalate to vasopressors

urine output below 0.5 mL/kg/hrUOP < 0.5 mL/kg/hr

Clinical Pearl

New confusion + tachycardia + any infection source = think sepsis first, prove otherwise later — and start the clock at recognition, not the ICU door.