Anesthetic management for ommaya reservoir placement in an extremely preterm 500 gr. neonate: case report.

We report the anesthetic management of a 27-day-old, 500-gram female infant (birth weight 580g), born at 246/7 weeks gestation, undergoing Ommaya reservoir place- ment for progressive posthemorrhagic hydrocephalus. It underscores the multidisciplinary perioperative chal- lenges inherent in caring for extremely low birth weight (ELBW) infants with significant comorbidities, including cardiorespiratory compromise and evolving grade III in- traventricular hemorrhage (IVH). Critical anesthetic strategies included: strict, milliliter-precise fluid re- striction; ventilation management using the existing mo- bile ventilator in synchronized intermittent mandatory ventilation with volume guarantee (SIMV-VG) mode, maintaining permissive hypercapnia; pharmacologic mi- crodosing with microgram-range opioids and muscle re- laxants; and continuous hemodynamic support via ti- trated inotrope infusion. The infant tolerated the 20-mi- nute procedure without hemodynamic instability, respir- atory deterioration, or exacerbation of metabolic acido- sis. This case demonstrates the feasibility of neurosurgi- cal interventions in infants at the extreme lower limit of viability (500 grams) when supported by precision anesthesia techniques tailored to extreme physiological immaturity.