NR240 Nursing II

1. NR240Nursing II Care of clients with coma & increased intracranial pressure Review self study slides 1-6

2. Structure of Neurons Mechanism of nerve impulse conduction Neurotransmitters Acetylcholine Serotonin Dopamine Norepinephrine Structures of the brain Supratentorial/infratentorial Cerebral circulation Circle of Willis Blood-brain barrier Cerebrospinal fluid circulation Spinal cord structures Ascending tracts Spinothalamic tracts Spinocerebellar tracts descending tracts Extrapyramidal tracts Basal ganglia Peripheral nervous system Sensory receptors Plexuses Lower motor neuron Reflexes Cranial nerves Review Chapt 43 neuro A & P key terms

3. Review Chapt 43 neuro diagnostic assessment Emphasize understanding of prep, indications and outcomes • Radiographic exam • Cerebral angiography • CT scanning • MRI • MRA • EEG • EMG • Lumbar puncture

4. Review Terms related to Coma • Obtundation • Reduced alertness • Lethargy • Abnormal drowsiness • Persistent vegetative state • state results when the cerebrum, which controls thought and behavior, is destroyed, but the thalamus and brain stem, which control sleep cycles, body temperature, breathing, and heart rate, are spared • Locked- in state • people are conscious and able to think but are so severely paralyzed that they can communicate only by opening and closing the eyes in response to questions

5. Review Terms related to Coma • Delirium • state of acute confusion, inattention, and altered level of consciousness (LOC), usually abrupt in onset (over several hours to several days). • Stupor • is an unresponsive state from which a person can be aroused only briefly and with vigorous, repeated attempts. • Coma • is an unresponsive state from which a person cannot be aroused, even with vigorous, repeated attempts. • Brain death • brain has permanently lost the ability to perform all vital functions, including maintenance of breathing

6. Defining Altered Mental State • Change in neurological function on a continuum affecting: • Arousability • Cognition, verbal response • ability to follow commands • Motor function • Sensory function • Presence of reflexes

7. Neurological Assessment • Level of consciousness (LOC),Mental status • Cognition, emotional status • cranial nerves • reflexes • motor function • Cerebellar • strength • sensory function

8. Eliciting a Focal Neurological Deficit • A deficit that occurs in any of the areas of neurological exam • Does not need to be all-encompassing • May be focused in one area or a few areas that are related • Can manifest in and effect: • Level of consciousness, motor, sensory, reflexes, cranial nerve function • Elicited through comprehensive assessment

9. Performing a neurocheck • Rapid neurocheck: • Glasgow coma scale (eye opening, motor response, verbal response) • Pupilary response • Motor strength • Vital signs • Sensation • Seizure activity

10. Documenting Neuro status • Neurological Flowsheet • Key points • Must be compared to baseline • Must evaluate right and left separately when possible • Should be performed with vital signs • Physician notification must be timely

11. Reporting criteria based and neurocheck results • Drop in GCS of 2 points or more • Deterioration in neuro status • Abnormal vitals signs: • rising systolic with unchanged diastolic (widened pulse pressure), bradycardia and change in respiratory pattern (Cushings triad) • Rising body temperature (can increase brain oxygen demand) • New onset seizure activity • CSF leakage

12. Acute changes requiring emergency intervention Notify MD within 5 minutes of discovering: • Unilateral pupil dilation, • Loss of pupil response • Abnormal flexion or extension • Loss of brain stem reflexes (gag reflex, corneal reflex) • Initiate emergency response • Ensure airway, provide oxygen, increase frequency of assessment establish IV access

13. Abnormal posturing • Decorticate • Decerebrate

14. Brain stem reflexes (3 types) • Caloric stimulation Cold calorics video (performed by MD) Injection of 20-30 cc syringe with an 18 gauge angiocath filled with ice water and squirted into the ear while evaluating eye movement. In a Normal response, eyes conjugately deviate away from the cold ear, then snap back to midline • Corneal Reflex Touch the lateral lower corner of the cornea. In a Normal response, ipsalateral eye blinks • Cough, gag reflex Jiggle the endotracheal tube or NG tube to stimulate the larynx or pharynx In a Normal response, patient coughs or gags

15. PC: neurologic dysfunction (AMS/Coma) Change in mental status new onset focal neurological deficit • Perform a comprehensive assessment (see next slide) • Evaluate possible cause or contributing problem (see etiology) • Monitor results of rule out lab/diagnostics (see workup) • Treat the underlying cause • Provide supportive care until reversed • NIC: hemodynamic monitoring • NIC: Neurological monitoring • Report acute declines in LOC, pupillary changes, abnormal posturing, • abnormal brainstem reflexes and initiate • NIC: shock management

16. Perform comprehensive Assessment • Determine if the individual has a history of altered mental states • Assess the current signs and symptoms of AMS • Determine if the patient is at high risk for developing AMS • focus on correctly identifying the causes of AMS • Define the duration and course of symptoms

17. Evaluate possible cause of AMS • Determine if conditions or situations that may affect mental status are present: • Medications/non-compliance with regimen • Fluid or electrolyte imbalance • Infections • Hypo- or hyperglycemia • Recent hospitalization • Recent surgery under general anesthesia • Recent change in living situation or environment • Recent fall or other trauma

18. Evaluate possible cause of AMS (cont’d) • Significant pain • Alcohol or drug abuse • Hypo- or hyperthyroidism • Nutritional deficiency • Recent stroke or seizure • Primary metastatic brain tumors or other malignancies • Cardiac arrhythmia/myocardial infarction • Always review the patient's medications, as these are a common source of AMS

19. Perform Lab/diagnostics to rule out cause • Electrolytes, BUN, glucose, creatinine, serum osmolality/urine sodium (to identify fluid/ electrolyte imbalance) • Urinalysis and/or urine culture (if urinary tract infection is suspected) • TSH/free T4 (to identify possible thyroid dysfunction) • Complete blood count (CBC) (if infection, inflammatory processes, bleeding, or anemia are suspected) • Chest x-ray/Oxygen saturation (if pneumonia or pulmonary embolism are suspected) • EKG/rhythm strip (if a cardiac arrhythmia or other heart dysfunction is suspected) • Albumin (if undernutrition is suspected) • Serum drug levels, when appropriate

20. Perform Lab/diagnostics to rule out cause • Radiological examination • CT • MRI

21. Nursing Priorities for the unconscious client (source: Carpenito) • PC: Respiratory insufficiency • PC: Pneumonia/Atelectasis • PC: Increased intracranial pressure • PC: Seizures • PC: Sepsis • PC: Thrombophlebitis • PC: Fluid/electrolyte imbalance • PC: Negative nitrogen balance • PC: Bladder distention • PC: Stress ulcers • PC: Renal calculi • PC: Urinary tract infection

22. Nursing Priorities for the unconscious client (source: Carpenito) cont’d • Nursing Diagnoses • Infection, Risk for related to immobility and invasive devices (tracheostomy, Foley catheter, venous lines)• • Risk for Tissue Integrity, Impaired: Corneal related to corneal drying secondary to open eyes and lower tear production • Family Anxiety/Fear related to present state of individual and uncertain prognosis• • Risk for Oral Mucous Membrane, Impaired related to inability to perform own mouth care and pooling of secretions• • Total Incontinence related to unconscious state • Disuse Syndrome • Powerlessness (family) related to feelings of loss of control and restrictions on lifestyle • Risk for Ineffective Airway Clearance related to stasis of secretions secondary to inadequate cough and decreased mobility

23. Understanding ICP

24. Mean Arterial Pressure • Calculation of systolic and diastolic blood pressure that indicates the degree of tissue perfusion to vital organs • Equation:  • Mean Arterial Pressure ~= 1/3 * SBP + 2/3 * DBP • Usual range:  70-110 • Should exceed 70 to ensure cerebral tissue perfusion

25. Cerebral perfusion pressure (CPP) • Cerebral perfusion pressure (CPP) is a measure of adequate supply of blood to cerebral tissue. • CCP=MAP - ICP

26. cerebral blood flow (CBF) • cerebral blood flow (CBF) is ensured through regulation of arterial blood supply and cerebrovascular resistance (CVR) • CBF=CPP ÷ CVR. • Determinants of supply occur as a result of: • Vasomotor control of cerebral arteries • Influenced by circulating levels of carbon dioxide, oxygen, products of metabolism, and pH. • Autoregulatory response to changes in MAP

27. Factors contributing to Cerebral arterial vasodilation to preserve Cerebral blood flow

28. Factors contributing to Cerebral arterial vasoconstriction to preserve Cerebral blood flow

29. Maladaptation in Autoregulation • Decreased systolic BP results in decreased CPP • Decreased CPP leads to increased vasodilation • Increased vasodilation increased cerebral blood volume • Increased cerebral blood volume increases ICP which in turn decreases cerebral perfusion pressure and the cycle repeats itself

30. Defining Intracranial Pressure • measure of pressure inside the cranium • has an arbitrary numeric amount • Can be monitored using pressure devices • Intracranial pressure monitoring

31. Causes of an increased ICP • Conditions Increasing Brain Volume • intracranial mass (tumor, hematoma, aneurysm, AVM) • cerebral edema • CNS infection (abscess, inflammatory process) • Conditions Increasing Blood Volume • obstruction of venous outflow • hyperemia • hypercapnea • Conditions Increasing CSF Volume • increased production • decreased reabsorption of CSF (meningitis, SAH) • obstruction to flow of CSF

32. High Risk Populations for Increased ICP • Intracerebral masses • blood clots • blockage of venous outflow • head injuries • inflammatory diseases • cranial surgery

33. Physiology of Intracranial Pressure • The cranium is a fixed box containing brain tissue, blood and CSF that can not readily accommodate increasing volumes because it can not expand. It has similar properties to a suitcase; its size is fixed and it contains an assortment of necessary things but there is a limit as to what you can put in it.

34. Physiology of Intracranial Pressure • When the volume inside the cranium is subject to stressors that can increase it precipitously, it results in an increase in intracranial pressure. • Such events include; • Cerebral vasodilation and edema, decreased venous return, masses and lesions It is like an overstuffed suitcase

35. Physiology of Intracranial Pressure • Intracranial pressure must be normalized to ensure adequate function of the Central Nervous system • Normal ICP is 10-15 mm Hg • This is accomplished by shunting CSF( to lumbar subarachnoid space), returning venous blood to the heart, and, if necessary, shifting away from the site of edema inside the skull. SHUNTING SHUNTING It would be like packing the extra stuff into a second suitcase SHUNTING

36. Relationship of volume to pressure Monroe-Kellie Hypothesis to maintain a normal ICP, a change in the volume of one compartment must be offset by a reciprocal change in the volume of another compartment

37. When you have too much in your suitcase, you have to unpack some of it Your brain needs to do the same thing when the ICP is too high.

38. Physiology of Intracranial Pressure • If the stressors that increase volume are too great inside the cranium it becomes difficult to get anything else in such as; • Oxygenated blood and nutrients, exacerbating cerebral edema and intracranial pressure The only way you could get anything else in is by force

39. Physiology of Intracranial Pressure • Mean arterial pressure will reflexively rise to overcome a rising intracranial pressure to restore perfusion There is only just much force that can be applied

40. Physiology of Intracranial Pressure • If the pressure elevated too markedly, the brain tissue will displace through the foramen occipitalis. • This is referred to as brain herniation The suitcase will open and its content will spill over

41. Profound Neurological dysfunction Progressive loss of consciousness Coma Irregular breathing Respiratory arrest (no breathing) Irregular pulse Cardiac arrest (no pulse) Loss of all brainstem reflexes (blink, gag, pupillary reaction to light) Source Medline plus Determining brain death Brain Herniation

42. Management of increased ICP • Identification of clients at risk • Initiation of ICP monitoring if indicated • Airway maintenance and ventilation • Oxygenation and low normal PaCO2 • Fluid balance to maintain cerebral perfusion • Avoiding positions that increase ICP • Sedation and decreased external stimulation • Osmotic and loop diuretics • Temperature maintenance • Blood glucose control • Pain management and stool softeners • See ICP sheet

43. Definition of ICP monitoring • type of device that is calibrated to detect the internal pressure readings • Interpretation of the readings assist in guiding actions to restore cerebral tissue perfusion. • Types • Ventriculostomy • Subarachnoid • Epidural • Subdural • Parenchymal

44. Types of Intracranial Pressure Monitoring Devices see page 1059

45. Indications for ICP monitoring • Head injury • Craniotomy • Intracranial hemorrhage • Cerebral edema

46. Goal if ICP monitoring • CFS clear • ICP< 20 • CPP between 60-75

47. Strategies to maintain normal ICP Source: UNC Policy and Procedure

48. Actions to avoid that can increase ICP Source: UNC Policy and Procedure

50. Collaborative care • PC: CNS infection • For all types of devices • PC: brain herniation • For devices that communicate with CSF and become obstructed • PC: decompression hemorrhage • For devices that communicate with CSF and rapidly empty ventricle