Transcript
Chapter 15: Determinants and Assessment of Cerebral Perfusion
Critical Thinking Checkpoint Case Studies
R.J. is a 24-year-old man who suffered a three-story fall at his place of employment as an engineer. He was verbal at the scene of the accident but subsequently had a rapid decrease in his level of consciousness. R.J. was transported by emergency medical helicopter services to an Emergency Department (ED) after his airway was secured. Once evaluated in the ED, he underwent an emergent head CT scan that revealed a large, 3-cm left epidural hematoma, right subdural hematoma, intraparenchymal contusions, and a basilar skull fracture. His right pupil was 4 mm, left pupil was 5 mm, and both were sluggishly reactive to light. His GCS was 6 (eyes 1, verbal 1, motor 4). He was emergently transported to the operating room for evacuation of the hematoma. During surgery, a left linear skull fracture located in the temporal area overlying a lacerated left middle meningeal artery was identified. R.J.'s condition improved following surgery-he was able to open his eyes to verbal command; he was unable to verbalize due to being intubated, but he was able to follow simple commands.
This activity contains 5 questions.
1. What is the patient's postsurgical GCS?
Answer: His GCS score was 10 (eyes 3, verbal 1, motor 6), and his pupillary reaction was at 3 mm briskly to light and bilaterally.
2. Clinical Update: Because of his improved neurological status, he was extubated. Unfortunately, his neurological status progressively deteriorated over the next 24 hours. By morning (24 hours after his injury), his GCS was 4 (eyes 1, verbal 1, motor 2), pupils were 6 mm nonreactive bilaterally, and he was reintubated orally. An intraventricular intracranial pressure catheter was placed that afternoon with an initial ICP of 24 mm Hg.
What conditions decrease CBF?
Answer: Low cardiac output, vasoconstriction, and cerebral edema. R.J. is at great risk of developing cerebral edema.
3. State three other types of ICP monitoring devices that are sometimes used in TBI.
Answer: Other types of ICP monitoring devices include the subarachnoid screw, intraparenchymal catheter, and the epidural probe.
4. What is the advantage of using an intraventricular ICP monitoring device over other monitoring devices?
Answer: Intraventricular monitors have a distinct advantage to the other systems in that CSF can be drained to treat elevations in ICP as well as monitor the ICP. It is considered the most accurate form of ICP monitoring.
5. What clinical assessment criteria will the critical care nursing staff need to monitor on an ongoing basis?
Answer: Vital signs, GCS, and neuro assessments; signs of CSF leak, such as rhinorrhea or otorrhea that might occur due to his existing basilar skull fracture; signs of seizure activity; pain and sedation control. ICP and CPP will also need to be monitored. Cerebral brain tissue oxygen monitoring will need to be considered as well. Hypotension and hypoxia will require immediate intervention to avoid potentiating further brain injury.
