Clinical Case Study Mr. Ayers's blood pressure continued to drop, so doctors ordered a chest X ray, ECG, and spiral CT scan (a rapid CT technique). These diagnostic tests revealed four fractured ribs,...

Clinical Case Study: Cardiovascular System: The Heart

Extracted text: Clinical Case Study Mr. Ayers's blood pressure continued to drop, so doctors ordered a chest X ray, ECG, and spiral CT scan (a rapid CT technique). These diagnostic tests revealed four fractured ribs, an enlarged mediastinum, and pericardial effusions (fluid in the pericardium) producing cardiac tamponade. Mr. Ayers was scheduled for emergency Cardiovascular System: The Heart Donald Ayers, a 49-year-old male, was the driver of the bus involved in the accident on Route 91. He was brought into the ER with blunt trauma to the chest. Paramedics noted that the driver's seatbelt had broken and that he was found lying under the instrument panel. Initially unresponsive, Mr. Ayers regained consciousness and complained of chest, epigastric, and left upper quadrant pain. Examination revealed mild tachycardia (110 bpm) and a blood pressure of 105/75 mm Hg. An exam 10 minutes later showed a rapid change in blood pressure (80/55 mm Hg) and HR (130 bpm) along with muffled heart sounds, a thready (weak) pulse, and bulging neck veins. Soon after, the patient began to complain of a sudden onset of pain that radiated into his back from the injury site. The patient described the pain as "sharp, stabbing, and tearing" and it continued to increase. surgery. 3. Beginning with the concept of end diastolic volume (ĒDV), explain the effect that the fluid in the pericardium is having on the stroke volume of Mr. Ayers's heart. 4. Muffled heart sounds are quieter and less distinct. Explain how changes in EDV can result in muffled heart sounds. 5. The final diagnosis in this case is a dissection (tear) of the aorta. From what you know about the anatomy of the heart, where in the aorta do you think the tear is located? Explain your answer. 1. Mr. Ayers's pulse is described as "thready." What might this indicate with respect to this patient's stroke volume? 2. Mr. Ayers's HR increased from 110 to 130 bpm. What effect will this have on his cardiac output? Explain your reasoning. 6. Why did Mr. Ayers's neck veins bulge?