INTRODUCTION

The U.S. Military has deployed combat assets throughout the world. Catastrophic injuries can occur in austere environments with limited or no resources. The standard of care for the treatment of severe Traumatic Brain Injury (TBI) includes the direct evaluation and treatment by a trained neurological surgeon.1,2,3 Because severe TBI can be rapidly fatal, and neurosurgical assets as well as timely critical care air transport of severely brain injured Service Members are not always feasible or available, the U.S. Military has recognized the potential need for non-neurosurgeons (usually general/trauma surgeons) to perform cranial procedures in a far forward setting.4 Data from the DoD Trauma Registry demonstrate that craniectomy procedures have been documented at Role 2 surgical facilities in Iraq and Afghanistan at least 36 times, with indeterminate success. There is some precedent for this practice within the literature,5-8 including reference to the need for this practice as early as World War II.8 This concept is briefly addressed in the treatise on War Surgery from the International Committee of the Red Cross.9 We acknowledge that neurosurgical procedures are possible in austere locations with appropriate training and resources, yet fully recognize that “there is no substitution for a fully trained neurosurgeon in any health care system, whether military or civilian.” 3 It is the responsibility of the U.S. Military neurosurgical community to ensure that our deployed Service Members receive the best care possible from non-neurosurgical colleagues. The purpose of this Clinical Practice Guideline (CPG) is to provide specific and tailored guidelines for the performance of cranial procedures by non-neurosurgeons. The document has been developed jointly by the neurosurgeons of all three services to support the non-neurosurgeon faced with this difficult situation.

This CPG was developed by consensus opinion from the Joint Trauma System (JTS), neurosurgical members of the American Association of Neurological Surgeons/Congress of Neurological Surgeons (AANS/CNS), Joint Military Committee and the AANS/CNS Section of Neurotrauma. This document has been reviewed by and is supported by the Defense and Veterans Brain Injury Center.

#### Definitions

Craniotomy: The removal of part of the skull for the purposes of accessing contents of the calvarial vault, and then replacing the bone in its original position using plates and screws.

Craniectomy: The removal of portions of the skull for the purposes of accessing the contents of the calvarial vault without replacement of the bone.

Ventriculostomy: The placement of a silastic catheter within the body of the lateral ventricle through a small burr hole drilled approximately 10-11 cm posterior to the glabella and 2.5-3 cm lateral to midline. This catheter can be used to drain cerebrospinal fluid and to measure intracranial pressure.

Subdural hematoma: The accumulation of blood within the subdural space, usually as a result of trauma, and best diagnosed with a computerized tomography (CT) scan. Indications for surgery include hematomas > 1 cm in maximal thickness especially if associated with > 5 mm midline shift on a non-contrast CT of the head.

Epidural hematoma: The accumulation of blood within the epidural space, usually as a result of trauma, and best diagnosed with a CT scan. Common locations include the temporal region (middle cranial fossa) due to laceration of the middle meningeal artery. Some general indications for surgical intervention may include a hematoma > 30 mL in size on non-contrast CT head, especially if associated with evidence of uncal herniation. This can be clinically diagnosed when there is a dilated, unreactive pupil (3rd cranial nerve compression) with contralateral hemiparesis, with or without hemodynamic instability (hypertension, bradycardia, respiratory variation).

Intracerebral hemorrhage: The accumulation of blood within the parenchyma of the brain. This can result from trauma and is best diagnosed with a CT scan.

Penetrating brain injury: Injury to the brain resulting from penetration of the skull, dura, and brain parenchyma by a foreign body.