Pulmonary and Critical Care Medicine
Astra Clinical Library
Critical care
Practical critical care guides for clinical decisions, with cited evidence, testing strategies, and actionable next steps.
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Pulmonary and Critical Care Medicine
Respiratory Failure
Acute respiratory failure requires parallel stabilization and etiologic diagnosis. Distinguish hypoxemic from hypercapnic physiology, identify airway or ventilatory-support failure early, select oxygen, high-flow, noninvasive, or invasive support by mechanism and trajectory, and reassess continuously for treatment failure.Critical Care Medicine
Septic Shock
Septic shock requires parallel source-directed therapy and physiology-guided resuscitation. Identify infection-associated organ dysfunction, obtain cultures without delaying antimicrobials, assess fluid responsiveness dynamically, initiate norepinephrine promptly for persistent hypotension, and repeatedly reassess perfusion, source control, and evolving organ failure.Critical Care Medicine
Abdominal Compartment Syndrome
Abdominal compartment syndrome is new organ dysfunction caused by sustained intra-abdominal hypertension. Diagnosis requires standardized bladder-pressure measurement in at-risk critically ill patients; management combines rapid pressure-reducing measures, source-directed drainage when feasible, and timely decompressive laparotomy for refractory organ dysfunction.Neurology and Neurocritical Care
Status Epilepticus
Status epilepticus requires immediate seizure termination, cardiorespiratory support, etiologic evaluation, and EEG-guided escalation. Adequate early benzodiazepine dosing and prompt loading with a second-line antiseizure medication reduce avoidable progression to refractory status, while persistent impaired consciousness mandates assessment for nonconvulsive seizures.Neurology and Neurocritical Care
Subarachnoid Hemorrhage
Spontaneous subarachnoid hemorrhage requires immediate noncontrast CT, escalation to lumbar puncture when suspicion persists after negative imaging, identification and early exclusion of an aneurysm, specialized neurovascular care, and prevention of delayed cerebral ischemia with nimodipine and vigilant vasospasm surveillance. [7]Endocrinology and critical care
Thyroid Storm
Thyroid storm is a clinical diagnosis of decompensated thyrotoxicosis with acute organ dysfunction. Immediate ICU-level multimodal therapy, treatment of the precipitant, and cautious cardiovascular management are required; thyroid hormone concentrations do not distinguish storm from uncomplicated thyrotoxicosis.[8]Neurology and Neurocritical Care
Intracranial Hemorrhage
Intracranial hemorrhage requires immediate localization, cause-directed imaging, reversal of anticoagulation when present, and early neurosurgical or neurocritical care triage. Outcomes depend on hemorrhage compartment, hematoma expansion, ventricular involvement, hydrocephalus, blood pressure, and timely control of secondary injury.Cardiology and Critical Care Medicine
Cardiogenic Shock
Cardiogenic shock requires immediate recognition of tissue hypoperfusion, rapid identification of a reversible cause, phenotype-directed vasoactive support, serial reassessment, and early escalation or transfer when pharmacologic support cannot preserve end-organ perfusion.Critical Care Medicine
Distributive Shock
Distributive shock is acute circulatory failure from pathologic vasodilation and maldistributed flow. Rapidly identify the precipitant, assess for concurrent hypovolemic, cardiogenic, or obstructive physiology, treat the cause, restore perfusion with individualized fluid resuscitation, and initiate vasopressors without delaying definitive therapy.[14][15]Pulmonary and Critical Care Medicine
Acute Pulmonary Embolism
Acute pulmonary embolism requires probability-guided testing, rapid assessment for cardiopulmonary failure, immediate anticoagulation when indicated, and selective escalation to reperfusion therapy. Contemporary multisociety guidance emphasizes integrated clinical, hemodynamic, respiratory, biomarker, and right-ventricular assessment to guide disposition and treatment.Critical Care Medicine
Bacterial Sepsis
Bacterial sepsis requires immediate recognition of infection-associated organ dysfunction, parallel microbiologic evaluation and resuscitation, prompt empiric antibiotics when illness is critical, source-directed control, and repeated reassessment to narrow therapy and identify noninfectious mimics.Emergency Medicine, Trauma Surgery, Critical Care
Hemorrhagic Shock
Hemorrhagic shock demands immediate recognition, mechanical hemorrhage control, rapid blood-product delivery, and parallel definitive operative or endovascular management. This review emphasizes time-sensitive actions, reassessment, trauma-specific diagnostic limitations, and important evidence gaps in resuscitation targets and adjunctive pharmacotherapy.Critical Care Medicine
Neurogenic Shock
Neurogenic shock is acute distributive shock after high spinal cord injury, driven by loss of sympathetic tone and often accompanied by bradycardia. Immediate priorities are trauma resuscitation, exclusion of hemorrhage and other shock states, invasive hemodynamic monitoring, and blood-pressure augmentation while definitive spinal evaluation proceeds.Critical Care Medicine
Shock
Shock requires simultaneous resuscitation and etiologic diagnosis. Recognize tissue hypoperfusion before sustained hypotension, establish monitoring and access, use focused bedside testing to identify the hemodynamic phenotype, and rapidly deliver source- or mechanism-directed treatment while reassessing perfusion and treatment response.Pulmonary and critical care medicine
Pneumothorax
Pneumothorax management hinges on immediate recognition of physiologic compromise, accurate imaging in stable patients, and selecting observation, aspiration, drainage, ambulatory care, or definitive surgery according to cause, symptoms, recurrence risk, and ability to ensure follow-up.Pulmonary and Critical Care Medicine
Dyspnea
Dyspnea requires rapid separation of airway, pulmonary vascular, parenchymal, cardiac, metabolic, and neuromuscular causes. Initial physiologic severity determines disposition; targeted bedside imaging, ECG, biomarkers, pulmonary testing, and exercise evaluation then identify the mechanism driving symptoms and direct treatment.Pulmonary and Critical Care Medicine
Bacterial Pneumonia
Manage suspected bacterial pneumonia by establishing illness severity and site of care, confirming a compatible pulmonary process, obtaining targeted microbiology in severe disease, and rapidly reconsidering alternative diagnoses or complications when empiric therapy fails.Pulmonary and Critical Care Medicine
Aspiration Pneumonia
Manage suspected aspiration pneumonia as community-acquired pneumonia unless resistant-pathogen risk is independently present, while distinguishing infection from aspiration pneumonitis, pulmonary edema, and obstructing or cavitary disease. Prioritize oxygenation, radiographic confirmation, targeted microbiology, swallowing evaluation, and prevention of recurrent aspiration.Pulmonary and Critical Care Medicine
Eosinophilic Pneumonia
Confirm pulmonary eosinophilia, triage hypoxemic acute disease, and identify an exposure, drug, infection, systemic disorder, or chronic idiopathic pattern before committing to corticosteroid treatment.Critical Care Medicine
Ventilator-Associated Pneumonia
Ventilator-associated pneumonia requires prompt empiric treatment when clinical suspicion is high, while respiratory sampling, serial reassessment, and culture-directed de-escalation limit overtreatment in a syndrome with imperfect diagnostic tests.Neurology and Neurocritical Care
Intracranial Hypertension
Intracranial hypertension requires rapid separation of mass effect, hydrocephalus, hemorrhage, venous thrombosis, and idiopathic disease; management prioritizes herniation prevention, cerebral perfusion, etiologic imaging, and vision-preserving intervention when papilledema or progressive visual loss is present.Pulmonary and Critical Care Medicine
Pleural Effusion
Evaluate pleural effusion by identifying instability or pleural infection, obtaining paired pleural-serum studies when sampling is indicated, and using fluid patterns to direct microbiology, cytology, biopsy, drainage, fibrinolysis, surgery, or durable symptom control.Hepatology and Critical Care
Acute Liver Failure
Acute liver failure requires immediate recognition of encephalopathy with INR greater than 1.5, etiologic triage, intensive monitoring for cerebral edema and multiorgan failure, early N-acetylcysteine when appropriate, and urgent coordination with a liver transplant center.Neurocritical Care
Diffuse Axonal Injury
Diffuse axonal injury should be suspected when impaired consciousness is disproportionate to CT findings after rotational head trauma. Management prioritizes severe TBI stabilization, detection of occult hemorrhagic axonal lesions with MRI, intracranial-pressure control, cautious prognostication, and early rehabilitation planning.Emergency Medicine and Neurocritical Care
Traumatic Brain Injury
Traumatic brain injury management hinges on early prevention of hypoxia and hypotension, CT-defined lesion recognition, timely neurosurgical escalation, and structured surveillance for intracranial hypertension and delayed functional sequelae.Emergency Medicine, Critical Care, Burn Surgery
Inhalation Injury
Manage inhalation injury as concurrent upper-airway edema, tracheobronchial and alveolar toxic injury, and carbon monoxide or cyanide poisoning. Early airway control, toxin-directed treatment, bronchoscopy-guided airway clearance, and serial respiratory reassessment address deterioration that can evolve after the initial examination.Cardiology and Critical Care
Cardiac Tamponade
Cardiac tamponade is a clinical obstructive-shock syndrome requiring rapid bedside echocardiographic assessment, recognition of context-dependent sonographic findings, and urgent drainage when impaired cardiac filling causes hemodynamic compromise.Critical Care Medicine
Noninvasive Ventilation Failure Criteria
Recognize NIV failure through serial physiology rather than oxygen saturation alone. Escalate promptly for worsening gas exchange, rising work of breathing, impaired consciousness, hemodynamic instability, or persistently high HACOR risk—especially in hypoxemic respiratory failure and moderate-to-severe ARDS.Pulmonary and Critical Care Medicine
High-Flow Nasal Oxygen Escalation
Escalate beyond high-flow nasal oxygen when oxygenation, respiratory effort, mental status, or hemodynamics worsen despite treatment; serial ROX assessment can identify patients needing prompt intubation evaluation before prolonged noninvasive support masks clinical deterioration.Pulmonary and Critical Care Medicine
Pleural Effusion Thoracentesis Indications
Perform diagnostic thoracentesis for a safely accessible effusion without a clear systemic cause, especially when infection, malignancy, or another exudative process is possible. Use ultrasound to establish procedural feasibility, obtain paired serum studies, and let fluid pH, microbiology, and cytology determine urgent drainage or tissue diagnosis.Pulmonary and Critical Care Medicine
Pleural Fluid Interpretation
Interpret pleural fluid by first identifying infection requiring drainage, then applying Light criteria, correcting pseudoexudates, and directing targeted tests for malignancy, tuberculosis, chylothorax, and other high-consequence etiologies.Pulmonary and Critical Care Medicine
Parapneumonic Effusion Drainage Criteria
Drain parapneumonic effusions when pleural fluid is purulent, microbiologically positive, markedly acidotic, or anatomically large or loculated. Use immediate blood-gas pH measurement after diagnostic thoracentesis to distinguish patients likely to resolve with antibiotics from those requiring image-guided tube drainage and escalation.Pulmonary and Critical Care Medicine
Hemoptysis Airway and Imaging Strategy
Manage hemoptysis by physiologic threat rather than reported volume: protect oxygenation and isolate the bleeding lung first, then use contrast-enhanced CT angiography in stable patients to identify cause, laterality, and target vessels for embolization.Critical Care Medicine
Shock Hemodynamic Assessment
Assess shock by confirming impaired perfusion, rapidly defining the dominant hemodynamic phenotype with bedside ultrasound and dynamic testing, then escalating to invasive monitoring when initial resuscitation fails or mixed cardiopulmonary physiology makes further fluid, vasopressor, or inotrope decisions uncertain.Critical Care Medicine
Vasopressor Weaning
Wean vasopressors only after sustained perfusion and correction of the shock driver, using protocolized dose reductions with MAP monitoring. In septic shock receiving norepinephrine plus vasopressin, discontinuation order remains uncertain; avoid treating either sequence as mortality-determining.Critical Care Medicine
Lactate Interpretation
Interpret lactate as a dynamic marker of metabolic stress, hypoperfusion, and impaired clearance—not a stand-alone measure of tissue hypoxia. Use the initial value to identify high-risk shock, then reassess perfusion, organ function, and trajectory to direct escalation without pursuing normalization blindly.Critical Care Medicine
Spontaneous Breathing Trial Failure
Spontaneous breathing trial failure should trigger targeted reassessment of respiratory load, cardiac reserve, diaphragm function, airway protection, secretion burden, and sedation rather than repeated unstructured trials. Distinguish failure of unsupported breathing from extubation risk after a passed trial.Critical Care Medicine
Sedation Selection
For mechanically ventilated adults, set a measurable light-sedation target, treat pain and reversible agitation drivers, and generally select propofol or dexmedetomidine rather than benzodiazepine infusions. Hemodynamic trajectory, need for rapid awakening, and bradycardia risk determine the preferred nonbenzodiazepine agent.Critical Care Medicine
Delirium Assessment in the ICU
Use a structured arousal-first approach: establish wakefulness with RASS, then screen assessable ICU patients serially with CAM-ICU or ICDSC. A positive screen should trigger medication, physiologic, infectious, neurologic, and environmental review rather than reflex antipsychotic treatment.Critical Care Medicine
Nutrition Initiation in Critical Illness
Initiate enteral nutrition early once shock is controlled and gastrointestinal perfusion is credible, then advance cautiously according to nutritional risk, measured or estimated energy needs, tolerance, and the route’s safety profile.Endocrinology and Critical Care Medicine
Thyroid Storm Treatment Sequence
Treat suspected thyroid storm as an ICU emergency: resuscitate and treat the trigger while rapidly blocking adrenergic effects, hormone synthesis, hormone release, peripheral conversion, and enterohepatic recirculation in a timed sequence.Critical Care Medicine
Mechanical Ventilation Liberation
Liberate invasive ventilation through a daily, coordinated readiness assessment: reverse the indication for intubation, minimize sedation, perform a spontaneous breathing trial, then separately judge airway protection, secretion clearance, and need for prophylactic post-extubation support.Pulmonary and Critical Care Medicine
Community-Acquired Pneumonia Admission Criteria
Determine CAP disposition by separating outpatient suitability from physiologic instability, then use PSI for mortality-oriented site-of-care assessment and ATS/IDSA severe-CAP criteria to identify patients needing ICU-level monitoring, ventilatory support, or vasopressors.Pulmonary and Critical Care Medicine
Aspiration Pneumonitis Versus Aspiration Pneumonia
Differentiate chemical lung injury after macroaspiration from bacterial aspiration pneumonia by exposure, tempo, trajectory, and complications; then prioritize airway protection, observation, standard pneumonia therapy when infection is likely, and prevention of recurrent aspiration.Critical Care Medicine and Infectious Diseases
Antibiotic De-escalation in Sepsis
For patients started on empiric broad-spectrum therapy for suspected sepsis, reassess infection likelihood, microbiology, source control, and clinical trajectory at 48–72 hours to stop unnecessary treatment, narrow active therapy, and use serial procalcitonin selectively to shorten exposure.Neurology and Neurocritical Care
ICH Blood Pressure Management
In acute spontaneous intracerebral hemorrhage, rapidly achieve smooth systolic blood pressure control near 140 mm Hg while avoiding overshoot hypotension, marked variability, and delays during the early hematoma-expansion window.Neurology and Neurocritical Care
Anticoagulant Reversal in Intracerebral Hemorrhage
Treat anticoagulant-associated intracerebral hemorrhage as a time-critical hematoma-expansion emergency: identify the agent and last dose, send agent-relevant assays without delaying treatment, administer targeted reversal promptly, and coordinate blood-pressure management, repeat imaging, and neurosurgical assessment.Neurology and Critical Care Medicine
Guillain-Barré Respiratory Monitoring
Guillain-Barré syndrome can progress rapidly to ventilatory failure despite modest limb weakness. Use serial bedside respiratory mechanics, bulbar assessment, and autonomic monitoring to identify patients needing ICU transfer and elective intubation before secretion failure, hypercapnia, or emergency airway loss.Neurology and Critical Care Medicine
Myasthenic Crisis Treatment Selection
Select plasma exchange or IVIG immediately for crisis or imminent respiratory and bulbar failure, while securing the airway, treating precipitants, and sequencing corticosteroids to avoid early worsening. Choice depends on physiologic urgency, access, contraindications, prior response, and complications.Pediatric Emergency Medicine and Critical Care
Pediatric Asthma Escalation
Escalate pediatric asthma care according to response to initial bronchodilation, oxygenation, work of breathing, and trajectory. This guide defines practical triggers for intravenous magnesium, continuous albuterol, noninvasive support, PICU transfer, intubation planning, and avoidance of low-value rescue therapies.Nephrology and Critical Care Medicine
Hyponatremia Overcorrection Management
Prevent osmotic demyelination by identifying patients at greatest risk, tracking sodium trajectory and urine output during active correction, arresting water diuresis with desmopressin, and promptly relowering sodium with electrolyte-free water when correction limits are exceeded.Nephrology and Critical Care Medicine
Dialysis Indications in Acute Kidney Injury
Initiate kidney replacement therapy urgently for refractory electrolyte, acid-base, fluid, or uremic complications—not creatinine alone. In severe ICU-associated AKI without an emergency indication, structured surveillance and standard initiation avoid unnecessary dialysis without improving survival through accelerated treatment.Critical Care Medicine
Sepsis Vasopressor Selection
Use norepinephrine early to restore a mean arterial pressure of at least 65 mm Hg after initial fluid resuscitation; add fixed-dose vasopressin during escalating requirements, reserve epinephrine for persistent hypotension, and reassess for cardiogenic or obstructive physiology when shock does not respond.Critical Care Medicine
Sepsis Fluid Reassessment
After initial crystalloid resuscitation for sepsis-induced hypoperfusion, reassess perfusion, fluid responsiveness, and congestion before each additional bolus. Passive leg raising with stroke-volume or cardiac-output measurement is the most broadly applicable dynamic test; persistent hypotension requires prompt vasopressor support rather than reflexive fluid loading.Critical Care Medicine
ARDS Ventilator Adjustment
Adjust ARDS ventilation by protecting the functional lung: use predicted-body-weight tidal volume, enforce plateau-pressure limits, titrate PEEP against recruitment and hemodynamic cost, prone early in moderate-to-severe disease, and refer promptly for VV-ECMO when protective targets cannot sustain gas exchange.Pulmonary and Critical Care Medicine
COPD Exacerbation Noninvasive Ventilation
Use bilevel noninvasive ventilation promptly for persistent acute hypercapnic acidosis during COPD exacerbation after initial therapy, while tightly titrating oxygen and reassessing pH, PaCO2, respiratory rate, tolerance, and need for intubation.Emergency Medicine and Critical Care
Pulseless Electrical Activity
Manage pulseless electrical activity as a nonshockable arrest: deliver uninterrupted high-quality CPR, give early epinephrine, verify true pulselessness, and simultaneously identify a reversible mechanical, metabolic, toxic, thrombotic, or hypoxic cause.Critical Care Medicine