Infectious Disease, Hematologic, and Oncologic Emergencies
Core concepts
Sepsis: suspect it with infection plus new organ dysfunction, check lactate, draw cultures, and give broad-spectrum antibiotics plus 30 mL/kg crystalloid for hypotension or lactate ≥4. Oncologic emergencies: febrile neutropenia requires an empiric antipseudomonal beta-lactam within 60 minutes, with vancomycin added for line infections or skin sources. Tumor lysis syndrome shows hyperkalemia, hyperphosphatemia, hyperuricemia, and hypocalcemia; treat with hydration and rasburicase (check G6PD). Hypercalcemia of malignancy responds to fluids, calcitonin, and a bisphosphonate. Spinal cord compression from metastatic disease needs dexamethasone and urgent MRI plus oncology consultation. Sickle cell emergencies: acute chest syndrome and splenic sequestration are transfusion emergencies. Hematologic: TTP (microangiopathic hemolysis with schistocytes, thrombocytopenia, neurologic or renal findings) requires urgent plasma exchange and ADAMTS13 testing - platelets are contraindicated. HIT uses the 4T score; stop heparin and start a non-heparin anticoagulant. DIC is treated by treating the cause; transfuse only for bleeding. Warfarin reversal is vitamin K plus four-factor PCC; DOAC reversal uses andexanet or idarucizumab where available.
Traps
Delaying antibiotics to obtain cultures or a lumbar puncture is a fatal error. Elderly or uremic patients may not mount a fever. Do not give platelets in TTP or HIT, and do not give FFP in DIC without bleeding. Steroids alone do not treat cord compression - the imaging and oncology pathway must start immediately.
Rule of thumb
In febrile neutropenia the clock is the enemy: order the antipseudomonal beta-lactam within 60 minutes of triage, and add vancomycin only when the presentation justifies it.