External ventricular drain insertion accuracy: is there a need for change in practice?

Abstract

Objective: Free-hand insertion of an external ventricular drain (EVD) is a common emergency neurosurgical procedure, mostly performed for critically ill patients. Although EVD complications have been studied thoroughly, the accuracy of EVD positioning has been audited only occasionally.

Methods: Post-EVD insertion computed tomographic scans performed in our unit over a 2-year period were analyzed for EVD tip location and intracranial catheter length.

Results: A total of 183 post-EVD insertion scans were reviewed. Of those, 73 EVD tips (39.9%) were in the ipsilateral frontal horn of the lateral ventricle (the desired target); of those, 18 (25%) required EVD revision/reinsertion. Of the others, 35 (19.1%) were in the third ventricle, 33 (18%) in the body of the lateral ventricle, 19 (10.4%) in the subarachnoid space, 5 (2.7%) in the contralateral frontal horn, and 18 (9.8%) within the brain parenchyma. When the EVD tip was outside the desired target, 44 of the patients (40%) required EVD revision/reinsertion procedure (P = 0.0383).

Conclusion: Free-hand insertion of an EVD is an inaccurate procedure, and further studies are required to assess the accuracy and feasibility of the routine use of neuronavigation, ultrasonography, or other guidance techniques and the possible implication of the decreasing revision rate, complications, and length of hospital stay.