Critical Care Time

US brain death assessment requires a known catastrophic brain injury, exclusion of physiological and drug confounders, absent brainstem responses and appropriate apnoea testing, with cerebral blood-flow studies used when clinical testing cannot be completed reliably.

A normal bicarbonate can conceal more than one metabolic process. A state–process–story approach uses pH, anion gap, strong ion difference and clinical context to distinguish respiratory failure or sedation from shock, bleeding or postoperative abdominal pathology.

A displayed oxygen saturation is only as reliable as pulsatile perfusion, probe position and signal quality. Delayed peripheral readings, pigmentation-related bias and hyperoxia limit interpretation, while suspected carbon monoxide poisoning or methaemoglobinaemia requires co-oximetry.

Critical-care and respiratory clinicians get an ARDS refresher covering alveolar-capillary leak, shunt, V/Q mismatch and reduced lung compliance. Practical management includes predicted-body-weight ventilation, plateau and driving-pressure review, early proning, dexamethasone, conservative fluid management, rescue therapies and palliative care alongside active treatment.

Critical-care, emergency and respiratory teams get a physiology-led airway strategy for refractory hypoxaemia, shock, severe metabolic acidosis and right ventricular failure. It links limited safe apnoea time with awake flexible endoscopic intubation, careful topicalisation, continued high-flow nasal oxygen and a prepared rescue plan.

Emergency and critical-care clinicians get a physiology-led approach to intubation in haemorrhagic shock, severe metabolic acidosis, hypoxaemic respiratory failure, pulmonary embolism and traumatic brain injury. It connects induction-related hypotension, apnoea, positive-pressure ventilation and right ventricular failure with preoxygenation, haemodynamic preparation, drug selection and team roles.

Critical-care, emergency and acute medicine clinicians get a detailed arterial-line update for shock, vasoactive titration, severe hypoxaemia, cardiac arrest and VA ECMO. It links decision-critical monitoring, ultrasound-guided insertion, site choice, securement, levelling, zeroing, damping checks and waveform interpretation to safer bedside decisions.

Critical-care clinicians get a wide physiology and evidence-appraisal mailbag. Fluid responsiveness, passive leg raise, ICU sleep, shunt physiology, lactate, DKA triggers, septic shock beta-blockade, airway difficulty and mechanical circulatory support are handled through bedside phenotype and measured response.

Critical-care, cardiology and emergency clinicians get a bedside approach to broad-complex tachycardia, VT storm and torsades. The useful distinctions are structural heart disease versus acquired long-QT triggers, with synchronised cardioversion, sedation, vasopressors, sympatholysis and device interrogation in view.

Allergy labels need phenotype, timing and severity before they reshape critical care choices. Alpha-gal syndrome, latex-fruit reactions, protamine hypersensitivity and iodine myths are used to separate true clinical risk from inherited labels that block useful treatment.