Case URL: http://sciencecases.lib.buffalo.edu/cs/files/blood_pressure.pdf Detect
ID: 3472562 • Letter: C
Question
Case URL: http://sciencecases.lib.buffalo.edu/cs/files/blood_pressure.pdf
Detective Garrison returned to police headquarters and, after reading the medical examiner's complete report, began the process of writing his own explanation of what happened to the Underhills. As he wrote, he thought about all that had happened and began to wonder about the physiology associated with the couples death. The level of alcohol found by the medical examiner was high but was not necessarily sufficient to cause their death, but was it a contributing factor? Sam knew that Lasix was used to treat high blood pressure and that both alcohol and heat will reduce blood pressure, but he was unsure of the mechanism. Me decided to go to Noletown University and talk to Rence Volenbach, a physiologist in the biology department, in her office in the McWhirter Biology building. Rence patiently explained her answer to each of the following questions posed by the detective. How does the body regulate blood pressure? What were the specific effects of the Lasix, hot water, and alcohol on the couples blood pressure? What could the body have done to reverse the decreasing blood pressure, if it had been possible? Identify several procedures that might have helped save the couple if they had been found unconscious but still above water and alive. Essay Put yourself in the role of Detective Garrison. You must now write a report explaining what Rence might have said with regard to the above questions. You should use all of your knowledge about blood pressure and the information from this case to explain each of the following aspects of blood pressure and discuss their relation to the above questions. Describe the role of the nervous system, adrenal glands, kidneys and pituitary as appropriate to the relation of each of the seven factors listed below: Peripheral resistance Heart rate Venous return Stroke volume Gardiac output End systolic and diastolic volumes Blood viscosityExplanation / Answer
1.Body regulates the blood pressure with the help of several chemoreceptors eg carotid sinus, baroreceptors eg carotid body, and mechanoreceptors eg stretch receptors in the body. Whenever these receptors detect any increase or decrease in the blood pressure of the body they send signals to the centres in brain eg Vasomotor centre which then gives impulses to rectify the changes occurring.
2.Lasix, hot water, alcohol cause vasodilation by inhibiting RAAS ie Renin Angiotensin Aldosterone System which acts on blood arteries to increase the blood pressure. Lasix and others decrease the peripheral resistance ie resistance faced by left ventricle (after load) on heart and increase venous return ie blood returned to the heart(preload). This increases the Stroke Volume and thus cardiac output(Heart rate × stroke volume). It also decreases the end systolic and diastolic volumes which is good for heart.
3. Their body could have activated RAAS which would increase blood pressure by above mechanism and also a beneficial effect on heart.
4. Cardiopulmonary resuscitation must be done at first.