Medical Surgical Nursing reviewer Neurologic function y Anatomy & physiology Neuron- functional unit of the brain. It is composed of a two cell body: Dendrite- conveys impulses toward the cell body and Axon- carries impulses away from the cell body. CNS: divided into three major areas. The cerebrum, cerebellum and brain stem. Cerebrum - consists of two hemispheres (left & right) joined by a fissure called Corpus callusom. The pair of lobes that subdivided the cerebral hemispheres are as follow: 1. Frontal- the largest lobe. Its function is for concentrations abstract thought, memory and motor function. It also contains Broca s area, for motor control of speech. 2. Parietal- predominantly sensory lobe. It analyzes sensory information and relays it to thalamus and other cortical areas. It is also essential for space and spatial relations orientation. 3. Temporal- auditory receptive area. Contains the interpretative area that provides integration somatization, visual and auditory areas. 4. Occipital- posterior lobe responsible for visual interpretation. hemispheres that divides the cerebrum: 1. hypothalamus- site for hunger center and appetite control. It also contains center for sleep- wake cycle, BP, sexual behavior and emotional responses. The hypothalamus also regulates the ANS. The Pituitary gland is also located in the sella turcica at the base of hypothalamus which is a common site of brain tumor in adults causing hormonal imbalances and visual disturbances. 2. Thalamus- encloses the third ventricle of the brain, is a relay station for all sensation (memory and pain) except for smell. 3. Basal ganglia- are responsible for control of motor movements including the hands and LE. Cerebellum- it is separated from the cerebral hemispheres by a fold of dura mater called tentorium cerebella. It s has both excitatory and inhibitory actions and is largely responsible for coordination of movement. It also controls fine movement, balance, position sense and integration of sensory input. Pia mater.outermost layer. salivation and swallowing. which separates the two hemispheres in a longitudinal plane. 2. Meninges. thick. It is also responsible in regulation of Blood vessel and heart. respiration. 3. There are four extensions of dura mater: falx cerebri. it is a tough. a thin. Portions of the pons also control the heart. which is an unfolding of the dura that forms a tough membranous shelf. falx cerebelli. which is between the the two laterals cerebral lobes. support and nourishment to the brain and spinal cord.smallest portion that connects the pons and cerebellum. It contains sensory and motor pathways and serves as the center for auditory and visual reflexes. thin. and BP. While the two vertebral arteries that branch from the subclavian arteries flow back and upward on either side of the cervical vertebrae and enter the cranium through the foramen magnum.contains motor fibers from the brain and sensory fibers from spinal cord to the brain. 3.fibrous connective tissue that provides protection.CN IX through XII connect to the brain in the medulla. a finger like projections responsible for CSF absorption(125.delicate membrane that closely resemble as a spider web and appears white because it lacks blood supply. inelastic.it approximately receives 15% or 750 ml/min of CO. Dura mater. which provides a roof for the sella turcica. and the diaphragm sellae. transparent layer that hugs the brain closely and extends into every fold of the brain surface. Brain stem. the tentorium. Cerebral circulation.150ml). Midbrain. respiration. The vertebral arteries join to become basilar . The two internal arteries that arise from the bifurcation of the common carotid supply much of the anterior circulation of the brain.middle. Pons. fibrous and gray part that covers the brain and the spinal cord. Medulla Oblongata. Arachnoid. the following are the layers of meninges: 1.situated in front of the cerebellum and it helps CN V through VIII to connect in the brain. 2. It also contains the choroid plexus which is responsible for CSF production(500 ml) and the arachnoid villi. the brainstem consists the following: 1.innermost.enlarged extension upwards within the skull of spinal cord. At the base of the brain surrounding the pituitary gland. a ring of arteries called circle of willis. Structure or act Neuro transmitters Heart rate RR GIT GUT Blood vessel Pupils Bronchioles Cranial nerves Cranial nerves I(olfactory) II(optic) III(oculomotor) Type Sensory Sensory Motor Function Sense of smell Visual acuity Muscles that move eye and lid.artery. corneal reflex. mastication Supplies motor fibers to the lateral rectus muscle(eye rolling) Sympa Effects E/ norE Increase Increase Decrease(constipation) Decrease(retention) Constrict Dilated Dilated Parasympa Effects Acetylcholine Decrease Decrease Increase Increase Dilated Constrict Constrict IV(trochlear) Motor V(Trigeminal) Mixed VI(Abducens) Motor . which is for Rest and Repose. lens accomodation Supplies motor fibers for one external eye muscle (SO) Facial sensation. Peripheral nervous system Sympathetic is for Fight and Flight in comparison with the Parasympathetic. provides collateral circulation if one or more of the four vessels supplying it are occluded(arterial anastomoses along the circle of willis is the common site of aneurysm). the basilar artery divides to form the two branches of the posterior cerebral arteries therefore supplying most of the posterior part of the brain. The cerebral veins and sinuses are unique because they do not have the valves to prevent blood from flowing backward and depend on the gravity and BP. pupillary constriction. or needs persistent stimuli to achieve state of alertness. parasympathetic innervations of thoracic and abdominal organs Sternocleidomastoid and trapezius muscle Movement of tongue VIII(acoustic) IX(glossopharyngeal) Sensory Mixed X(vagus) Mixed XI(spinal accessory) XII(hypoglossal) Motor Motor Spinal nerves( 31 pairs) a) 8 cervical b) 12 thoracic c) 5 lumbar d) 5 sacral e) 1 coccygeal Neurologic dysfunction y Altered level of consciousness (LOC) patient who is not oriented. sensation in pharynx and tongue. Restlessness and increase anxiety b. larynx and soft palate. pharynx. thoracic and abdominal viscera. larynx. sensation in the ear Hearing and equilibrium Taste. Clinical manifestation: a. sensation in external ear. taste. pharyngeal muscles Muscle of pharynx. Pupils becomes sluggish then fixed(comatose) . salivation and tearing.VII(facial) Mixed Facial expression and muscle movement. Pneumonia. Assessment: Glasgow Coma Scale Eye opening Spontaneous 4 response To voice 3 To pain 2 None 1 Best verbal response Oriented 5 Confused 4 Inappropriate words 3 Incomprehensible 2 sounds None 1 Best motor response Obeys command 6 Localizes pain 5 Withdraws 4 Flexion 3 Extension 2 None 1 *14-15: normal 11-13: lethargy (drowsy and sluggish) 8-10: stupor (mental inactivity and low response in stimulation) 7: coma 3: deep coma Complications: a. Mouth is cleansed and rinsed to remove secretions and to keep the mucous membrane moist. Pressure ulcers. Position. Prevent aspirations.ineffective airway due to altered LOC. . Lateral or semiprone for proper drainage. c. b. Elevate HOB 30 degrees angle or through suctioning. Respiratory failure. Client s safety. Fluid administration through IV.common for those who receives mechanical ventilation.due to immobility. Padded side rails are raised at all times and identifying potential sources that may injure the patient. Enteral feedings. Managing nutrition. Maintaining fluid balance. Nursing management: Establish an adequate airway and ensure ventilation. Providing mouth care. Changes in LOC (earliest indicator) such as restlessness. Insertion of indwelling catheter to inspect for urine and urinary output. internal rotation of the LE and planter flexion of the feet. Body temp should be taken rectally or tympanic for accuracy. Valsalva maneuver should be avoided too. Administration of osmotic and loop diuretics. b. c.involving extension and outward rotation of the UE and plantar flexion of the feet. Nursing interventions: Maintaining patent airway. c. y Increase intracranial pressure when there is no balance between the volume and pressure in the three component of the cranial vault. SIADH. Clearing secretions obstructing the airway through suctioning and by positioning the HOB elevated 0 to 60 degrees to aid in clearing secretions and improving venous drainage to the brain. Preventing urinary retention. The eyes may be cleansed with cotton balls moistened with NSS to remove derbis and if artificial tears are prescribed. d. Diabetes insipidus. Usually ICP is measured in the lateral ventricle. Promoting bowel function.due to increase secretion of ADH. Mannitol is intent to . Avoiding extreme rotation and flexion of the neck so jugular veins are not distorting that may cause increase ICP.Preserving corneal integrity. Brain tissue (1. Decerebration. blood (75ml) and CSF (75 ml).due to decrease secretion of anti Diuretic hormone. Optimizing cerebral tissue perfusion.due to pressure build up in the cranial vault that presses down the brain on the brain stem resulting in decrease blood flow causing brain anoxia and death. Complications: a. By assessing for distention through listening to bowel sounds and measuring the girth of the abdomen by a measuring tape. Slowing of speech and delay response to verbal suggestions.400g). Clinical manifestations: a. they may be instilled q2. Minimum drape is used to promote N Temp or the room maybe cooled if not contraindicated. b. Decortication-adduction and flexion of the UE. Brain stem herniation. Also by giving glycerin suppository to facilitate bowel emptying and enema every other day to empty the lower colon. Achieving thermoregulation. Corticosteroid is used to reduce cerebral edema and fluids must be restricted. N ICP is 10 to 20 mm Hg. RR(cheyne. bladder and bowel disorder.shift fluid from the intracellular compartment to the intravascular system. One which is through the skull used: above tentorium (supra tentorial) into the supratentorial compartment and below the tentorium into the infratentorial (posterior fossa) compartment. Medications to reduce cerebral edema include Mannitol. And Dexamethasone through IV that must be tapered when switch to oral route over 5 to 7 days. temp and BP rises. Detecting early indications of increasing ICP such as disorientation. swallowing. The surgeon cuts the skull to create a bony flap by two approaches. hemiplegia and loss of brain stem reflexes such as gag. thus controlling cerebral edema. and evacuate a blood clot and control hemorrhage. . restlessness. Post operative management: Reducing edema. Indwelling catheter is inserted to empty the bladder during administration of diuretics (mannitol and furosemide) and to monitor urinary output. corneal and pupillary. weakness in one extremity and headache that is constant. Relieving pain and preventing seizures. Detecting later signs if increase ICP such as LOC deteriorates going to coma. Aseptic technique is used when managing intraventricular catheter to prevent bacterial growth. mental confusions. relieve elevated ICP. y Intracranial surgery A craniotomy involves opening the skull surgically to gain access to intracranial structures to remove a tumor.strokes breathing:rhythmic waxing and waning of rate and depths of RR with periods of apnea. pupillary changes and impaired extraocular. ataxic breathing:irregulat deep and shallow breaths) and PR decrease. Writing materials or pictures and other frequently used items may help in communication if the patient is aphasic. Pre operative management: Evaluating LOC and responsiveness to stimuli and identifying neurological deficits such as paralysis. purposeful movements. Preventing infection. increasing in intensity and aggravated by movement or straining. alterations in speech. A transsphenoidal approach through the mouth and nasal sinuses is used to gain access to pituitary gland. The fluid is then secreted by osmotic diuresis. which increases serum osmolality and draw free water from areas of the brain. increase RR.