Sepsis: 3-Hour Bundle, Lactate-Guided Fluids, Norepinephrine & Source Control

Sepsis is life-threatening organ dysfunction from dysregulated infection. The winning sequence is simple but time-critical: recognize → cultures → antibiotics → fluids → vasopressors → source control, with lactate as your compass and frequent reassessment to avoid over-resuscitation.

Definitions that change decisions

• Sepsis: suspected/confirmed infection plus organ dysfunction (commonly SOFA ↑ ≥2).
• Septic shock: sepsis with persistent hypotension requiring vasopressors to keep MAP ≥65 and lactate >2 mmol/L despite adequate fluids.

Minute 0–10: stabilize & triage

• Airway, breathing, circulation; supplemental O₂ as needed.
• Two large-bore IVs; place on monitor. Check point-of-care glucose.
• Labs: CBC, CMP, lactate, PT/INR, PTT, VBG/ABG if hypoxic/acidotic, UA, cultures as below.

The 3-hour bundle (do these in parallel)

• Blood cultures ×2 (peripheral ± from lines) before antibiotics if this won’t delay therapy.
• Start broad-spectrum antibiotics within 1 hour of recognition. Cover likely source (lungs, urine, abdomen, skin/soft tissue, CNS) and local resistance. De-escalate at 48–72 h with culture data.
• Measure lactate and re-measure in 2–4 h if initially elevated to assess perfusion/response.
• Fluids: give balanced crystalloids for hypotension or lactate ≥4. Many pathways begin with up to ~30 mL/kg as a starting estimate, but individualize using dynamic assessments (see below) in CHF/CKD/elderly or when respiratory status is fragile.

Fluids: enough, not too much

• Prefer LR/Plasma-Lyte over large volumes of normal saline to avoid hyperchloremic acidosis.
• Dynamic tests beat static numbers: passive leg raise (PLR) with stroke volume response, stroke-volume variation, carotid VTI, or IVC/venous Doppler when skilled and feasible.
• Reassess every 15–30 minutes: mental status, capillary refill, skin temperature, urine output (>0.5 mL/kg/h), lactate trend, and signs of venous congestion (B-lines, JVP, hepatic/renal Doppler if available).

Vasopressors: don’t wait for a perfect tank

• If hypotension persists during fluids, start norepinephrine to target MAP ≥65. It’s safe to begin peripherally through a well-running large vein while arranging central access.
• Add vasopressin 0.03 units/min if escalating norepinephrine dose or to spare catecholamines.
• Consider epinephrine as next-line if MAP not achieved. Reserve phenylephrine for special cases (e.g., tachyarrhythmias) due to reduced splanchnic flow.
• Inotropy: use dobutamine for low cardiac output or persistent hypoperfusion despite MAP goal (echo/POCUS helps).
• Steroids: in refractory shock, hydrocortisone ~200 mg/day can reduce pressor needs—after source control and adequate antibiotics are in motion.

Source control (treat the cause)

• Drain pus: abscess/empyaema/pyonephrosis (IR, surgery).
• Remove infected hardware when feasible: lines, devices, necrotic tissue.
• Fix obstruction: obstructed kidney (stent/nephrostomy), perforated viscus, biliary obstruction (ERCP), ischemic bowel.
• Aim for definitive source control within hours (often <6–12 h) when physiologically safe.

Antibiotics: smart broad, then narrow

• Pick two-to-three drug coverage for high-risk sources (e.g., anti-pseudomonal beta-lactam ± MRSA agent; consider anaerobes for intra-abdominal). Follow local antibiogram.
• De-escalate promptly when cultures return; typical durations 5–7 days with good source control (longer for endocarditis, osteomyelitis, undrained foci).
• Renal-dose all agents and avoid nephrotoxin stacks where possible.

Perfusion endpoints you can use now

• Lactate clearance (downward trend over 2–6 h).
• Capillary refill time (CRT ≤3 sec) as a quick bedside check.
• Urine output ≥0.5 mL/kg/h, improving mental status, warmer extremities.

ICU care elements (brief)

• Lung-protective ventilation for ARDS: tidal volume ~6 mL/kg ideal body weight; plateau <30 cmH₂O; consider early prone positioning when severe.
• Glycemia: target ~140–180 mg/dL; avoid hypoglycemia.
• VTE prophylaxis and stress-ulcer prophylaxis when indicated.
• Transfusion: restrictive threshold around Hgb 7 g/dL in stable patients without active ischemia.

Special populations & caveats

• CHF/CKD/elderly: smaller aliquots, tighter reassessment, earlier pressors to avoid fluid overload.
• Pregnancy: lower threshold for early ICU and source control; fetal considerations with imaging/antibiotics.
• Immunocompromised/neutropenic: broaden empirically and involve ID early; cover for Pseudomonas promptly.

Pearls & pitfalls

• Antibiotics within the hour saves lives—don’t let “perfect cultures” delay therapy.
• Don’t drown the patient: use dynamic response to guide fluids; switch to vasopressors early if hypotension persists.
• Source control is definitive therapy—escalate to IR/surgery fast when indicated.

Patient FAQs

“Why so many drips?” One replaces fluid, one supports blood pressure, and antibiotics kill the infection while we fix the source.

“Will I need the ICU?” If blood pressure needs medication support or breathing is affected, ICU monitoring is safest.

References & Notes

Pragmatic sepsis pathway: early antibiotics, lactate-guided resuscitation with balanced crystalloids, norepinephrine to MAP ≥65 (add vasopressin/epinephrine as needed), and rapid source control. De-escalate antibiotics at 48–72 h. Local protocols vary—follow institutional guidance. Educational only.