Chapter 38: Assessment of the Nervous System

The level of consciousness and orientation assessment serves as the foundational element, as deterioration in consciousness represents the earliest and most sensitive indicator of declining central nervous system function and warrants immediate clinical attention. Cranial nerve evaluation, particularly assessment of the oculomotor nerve through pupillary response testing using the PERRLA protocol, provides critical information about brainstem integrity and intracranial pressure changes. Mobility assessment encompasses manual muscle testing against resistance, observation of abnormal involuntary movements such as pronator drift, and recognition of severe neurological compromise indicated by pathological posturing patterns including decortication and decerebration. Sensory testing using graded stimuli helps identify peripheral nerve involvement or ascending neurological deficits characteristic of conditions like Guillain-Barré syndrome. The chapter addresses age-related physiological changes affecting nervous system function, including prolonged cognitive processing time, selective memory decline, and balance alterations that necessitate targeted fall prevention strategies. Diagnostic procedures including magnetic resonance imaging, computed tomography scanning, and cerebral angiography are discussed with attention to patient safety protocols, such as screening for contraindications before imaging and managing post-procedural complications. Care following cerebral angiography requires vigilant monitoring of the puncture site for hemorrhage or thrombosis, extremity immobilization, and adequate hydration to prevent contrast-induced renal injury. The chapter emphasizes the Glasgow Coma Scale as a standardized tool for quantifying consciousness level and describes appropriate post-lumbar puncture monitoring for cerebrospinal fluid leakage and headache development. Throughout, the content stresses how subtle assessment findings guide clinical decision-making and enable early detection of neurological changes that prompt emergency intervention.