Direct measurement of intracranial pressure in adult horses.

The article details the development of a surgical method for accurately measuring intracranial pressure in horses; measurements that fall within range for other species and can serve as a diagnostic reference for abnormal intracranial pressure in horses.

Research Methods

• The study subjects were six healthy, adult castrated male horses of different breeds, inclusive of one Holsteiner, one Quarter Horse, and four Thoroughbreds.
• All subjects were anesthetized using isoflurane as the sole anesthetic agent.
• Catheters were inserted into the jugular vein and carotid artery of each horse percutaneously, that is, through the skin without need for a large surgical incision.
• A microsensor intracranial pressure (ICP) transducer was inserted into the right parietal craniotomy, specifically within the subarachnoid space — the area between the arachnoid membrane and the pia mater surrounding the brain.
• The burr hole made for placing the sensor was sealed using bone wax. The surgical incision was then sutured, securing the transducer in place.
• Post-anesthesia, once the horses regained the ability to stand, measurements of ICP were taken approximately an hour later.

Findings

• The mean measurements of ICP and cerebral perfusion pressures (CPP), inclusive of the standard deviation, were found to be 2 ± 4mm Hg and 102 ± 26mm Hg, respectively.

Conclusions

• The researchers posit that this minimally invasive surgical technique yields direct and accurate measurements of a horse’s ICP.
• Furthermore, the acquired ICP values displayed similarities to the reference ranges found in other species, affirming the validity of the developed method.
• Last but not least, the gathered data can be harnessed as a diagnostic reference point for identifying abnormal ICP in adult horses.