Clinical Anesthesia Management and Subspecialty Care
Obstetrics
After roughly 20 weeks of gestation, aortocaval compression dominates positioning decisions: left uterine displacement is mandatory during induction and maintenance. Neuraxial anesthesia is generally the preferred technique for cesarean delivery, including in preeclampsia, unless there is coagulopathy, infection at the site, or severe volume depletion. Magnesium therapy potentiates neuromuscular blockade, so reduce relaxant doses and monitor with a nerve stimulator.
Pediatrics
Bradycardia in an infant is a hypoxia equivalent until proven otherwise, and the treatment is oxygenation and ventilation. Weight-based dosing, uncuffed or cuffed tube sizing by age, and the lower functional residual capacity with higher oxygen consumption explain rapid desaturation. Laryngospasm is managed with jaw thrust, CPAP with 100% oxygen, and only then small-dose succinylcholine.
Neuroanesthesia
Cerebral perfusion pressure equals mean arterial pressure minus intracranial pressure. The two controllable variables are blood pressure and PaCO2: hyperventilation to 30–35 mmHg buys time during herniation, but prophylactic hyperventilation is not indicated. The sitting position carries venous air embolism risk; a sudden fall in end-tidal CO2 with hypotension is the classic clue.
Cardiac, regional, trauma
Understand shunt physiology before anesthetizing a cyanotic lesion, and treat the pulmonary vascular resistance as a fragile variable. For local anesthetics, know maximum weight-based doses and that lipid emulsion is the rescue for systemic toxicity. Trauma patients are full stomachs with difficult airways until proven otherwise - prioritize cervical protection and rapid sequence induction.
Worked example
MAP 70 mmHg, ICP 20 mmHg: CPP = 50 mmHg. Because targets are usually at least 60 mmHg, the answer is to raise MAP, not to hyperventilate reflexively.