perioperative– category –

Dead space explained: anatomic, alveolar, and physiologic types, VD/VT, PaCO₂–ETCO₂ gradient, with clinical notes on PE, pneumonia, and COPD (V/Q mismatch).

Basics of non-invasive blood pressure (NIBP): Korotkoff vs oscillometric methods, cuff size/position, ASA standards. For exam prep.

Clear explanation of pacemaker basics, perioperative checks, intraoperative settings, electrosurgery precautions, and troubleshooting. For anesthesiology board and perioperative team exams.

Are difficult mask ventilation and difficult intubation the same? Learn key differences, risks, and ASA 2022 airway guidelines.

How long does an oxygen cylinder last? Learn easy formulas with examples, cylinder factors, and safety margins explained clearly.

Oxygen therapy after anesthesia is routine, but why? This article explains the mechanisms of postoperative hypoxemia, why oxygen is supportive not curative, and the risks of excessive oxygen flow.

Functional Residual Capacity (FRC = RV + ERV) is the lung volume at end-tidal expiration, where lung and chest wall forces balance. It acts as an intrathoracic oxygen tank, crucial for safe apnea. General anesthesia, obesity, pregnancy, and supine positioning all reduce FRC, predisposing patients to atelectasis and hypoxemia. Preoxygenation and PEEP help preserve FRC and extend safe apnea time.

Why epinephrine for anaphylaxis? This article explains the mechanisms—α1 vasoconstriction, β1 cardiac support, β2 bronchodilation, and mediator suppression. We also review administration routes, pharmacokinetics, and safety considerations, with reference to major guidelines.

Gray (Gy) and Sievert (Sv) are both J/kg, but serve different purposes. Gy measures absorbed radiation energy, used in therapy and deterministic effects. Sv applies weighting factors for radiation type and organ sensitivity, estimating stochastic risk, used in protection and regulations. Includes analogy, quick reference table, and key ICRP dose limits.