Effect of craniectomy/durotomy alone and in combination with hyperventilation, diuretics, and corticosteroids on intracranial pressure in clinically normal dogs

Objective - To determine the effect of craniectomy and durotomy on intracranial pressure (ICP) in clinically normal dogs. Design - Two-part study (experiments A and B) involving craniectomy and durotomy, with and without treatments to lower ICP. Animals - Six (experiment A) and 7 (experiment B) healthy dogs. Procedure - In experiment A, craniectomy was performed in combination with durotomy, diuretic administration, methylprednisolone sodium succinate administration, and hyperventilation, and effect of these manipulations on ICP was determined. In experiment B, dogs had only craniectomy and durotomy without associated ICP-lowering treatments. During both experiments, ICP was monitored throughout the surgical procedure with a fiber optic ICP monitoring device. Results - Intracranial pressure decreased after the combination of craniectomy, durotomy, and other ICP-lowering treatments in dogs of experiment A. Similar magnitude of decrease in ICP was observed in dogs of experiment B after craniectomy and durotomy. Conclusions - Comparison of these experiments indicate that surgical removal of overlying skull and incision of the dura mater can significantly decrease ICP in clinically normal dogs. Clinical Relevance - Craniectomy and durotomy may be useful as an adjunct treatment for increased ICP.