Lab Final (1) PDF

1 Neuromuscular: Concept of reflex response: rapid, involuntary motor/muscle response to a stimulus Overall process: Stimulus → sensory neuron transmits it as sensory information → central nervous system processes it → generates a command → transmitted via motor neuron → muscle cont...

1 Neuromuscular: Concept of reflex response: rapid, involuntary motor/muscle response to a stimulus Overall process: Stimulus → sensory neuron transmits it as sensory information → central nervous system processes it → generates a command → transmitted via motor neuron → muscle contracts a. Spinal reflex- such as a reflex hammer with patellar reflex as an example, with tapping on tendon leading to stretching of a muscle which, as a stimulus, generates signal transmitted via sensory neuron/afferent neuron to CNS/spinal cord, which processes it and generates command transmitted via motor neuron/efferent neuron back to muscles of knee joint to contract, distal part of the leg will kick up. Motor= efferent Sensory= afferent This evaluates a number of things: - Central nervous system function - Spinal cord function - Peripheral nervous system function - Sensory and motor neurons - https://www.youtube.com/watch?v=c-dD0N53QRg b. Brain stem reflex (cranial nerves from brain stem): Pupillary light reflexes- with light as stimulus, leading to signal transmitted to the CNS (brain stem specifically) from the retina… leading to iris muscles contraction when light shines in to reduce the amount of light penetrating into eye, resulting in pupillary narrowing/constriction. In addition, when one eye is exposed to light, the other eye also responds reflexively, due to cross connections b/w right and left sides of the brain (control centers for vision). When something is picked up in one eye, the other eye picks it up This evaluates a number of things: - Central nervous system function - Brain stem function - Peripheral nervous system function  2 Cardiovascular Parameters: Blood pressure/Heart Rate: a. Vital signs: measurements reflecting essential/basic physiologic functions 1. blood pressure-driving force for blood flow (cardiac activity) 2. heart rate-cardiac activity, feel the pulsations 3. respiratory rate-lung function (breathing) 4. temperature-metabolism/cellular respiration. ii. Blood Pressure- measured as Systolic/Diastolic (with systolic BP generated by contraction of the left ventricle, and diastolic BP generated even when the left ventricle relaxes) using a blood pressure cuff/sphygmomanometer with a stethoscope to measure blood pressure. (Wrap it around the brachial artery.) 1. When cuff pressure is greater than systolic pressure, there is no blood flow, since the cuff pressure compresses the artery, and nothing can be heard (no blood flow); when systolic pressure is just greater than cuff pressure, flow resumes during systole and one hears the resumption of blood flow and continues to hear the flow due to the intermittent flow during systole only (which is a turbulent flow), but not during diastole, until cuff pressure is just below diastole at which time flow will be continuous and smooth and no sounds of flow anymore. a. Procedure of placing cuff over artery opposite elbow, inflating cuff well above expected systolic pressure and then gradually releasing/deflating cuff, while listening with the stethoscope for the first sound of flow resuming-systolic BP, and listening for when the sounds stop-diastolic BP. iii. Heart rate: feeling for radial pulse and measuring the ‘pulsations’ (expansions of artery during systole) for 15 seconds, then multiplying by 4 to calculate BPM-beats per minute. 1. Each pulsation represents one heart-beat (one cardiac cycle). a. Effect of exercise on heart rate, with an increase in HR to increase oxygen delivery to tissues requiring more energy during exercise. Ex. 110/70 1. Inflate to 180 mm Hg – strangles artery, no blood flow, won’t hear anything 2. Deflate to 110 (really 109) – when systolic blood pressure is greater, blood flow will resume 3. At 100– you hear a “swooshing” sound because it’s lower than systolic but higher than diastolic so flow is intermittent 4. At 70 (really 69) mmHg- blood is continuous, won’t hear anything  3 Cardiac Auscultation: listening to heart sounds with a stethoscope placed over the person’s chest area. a. Heart sounds are generated by the closing of heart valves. 2 basic heart sounds-S1 and S2. i. The 1st heart sound occurs when the valve b/w the left atrium and left ventricle closes/atrio-ventricular valve, which occurs at the beginning of systole. 1. “Lub” sound (left ventricle begins to contract) ii. The 2nd heart sound occurs when the valve b/w the left ventricle and aorta closes (aortic valve), which occurs at the beginning of diastole. (it also includes the right side, but just for reference purposes we’re focusing on the left side) 1. “Dub” sound (left ventricle begins to relax) 1 heart sound-systole; 2nd heart sound-diastole. One can also tell by the shorter time st interval b/w S1 and S2, than b/w S2 and the next S1. ○ (Diastole lasts longer than systole) EKG Monitoring: a. EKG: representation of electrical activity/action potentials of the heart/intrinsic electrical stimulating system of the heart. The heart has its own internal/intrinsic 'nervous system' (the nervous system can influence the heart activity, but the basic activity is stimulated from within). The signal/depolarization originates in the right atrium in the SA node; then travels/is transmitted to the right atrium and left atrium, stimulating them to contract; then to the AV node in the right atrium (at the border of the right atrium and right ventricle); then to the inter-ventricular septum; then to both ventricles, stimulating them to contract. SA node [in right atrium]→ Both atriums (they contract) → AV node [also in right atrium] → interventricular septum→ both ventricles (they contract) i. EKG can be used to measure heart rate, based on length of interval b/w one QRS complex and the next; and EKG is used to analyze/evaluate heart rhythms/patterns-consistent patterns or not/regular or not. Basic components of EKG: p wave-atrial contraction/depolarization (during diastole); QRS complex-ventricular contraction/depolarization (during  4 systole); T wave-repolarization of ventricles. P wave should always precede a QRS complex. Made with ChatGPT Measure heart rate, each square box (not the very tiny squares) = 0.2 seconds, with measuring time interval b/w the top of one QRS complex and the next by counting number of boxes b/w them, multiply the number of boxes by 0.2 60 (60 seconds per minute) divided by the number of boxes x 0.2, to calculate beats per minute; 60 divided by ​___________. From ChatGPT Be able to recognize normal heart rate: ○ bradycardia-below normal heart rate (longer intervals) ○ tachycardia- above normal heart rate (shorter intervals)  5 I’ll give you the normal values on the exam, which are 60-100 beats per minute (cardiac cycles per minute). Spirometry/Lung volumes-during breathing-inhale/inspire and exhale/expire: a. Tidal Volume-volume of air inhaled/exhaled per breath at rest b. Inspiratory reserve volume-additional volume one can inhale above the tidal volume during maximal inspiratory effort [shows us that there is a lot of reserve, it's not a fixed rigid structure] c. Expiratory reserve volume-volume exhaled above the tidal volume with maximum effort (which reflects CO2 being exhaled, very important) d. Residual volume-volume which remains in lungs even after maximal expiratory effort (can never be exhaled), which helps keep lungs/airways open even after exhaling (we aren’t starting from scratch), allowing for easier breathing/inhaling during the next breath; otherwise, if lungs/airways would empty completely, they would essentially collapse like a totally deflated balloon and be much more difficult to re-inflate. (residual volume also provides oxygen for gas exchange b/w lungs (alveoli) and blood even during exhaling) 2. Lung volumes/spirometry can help evaluate a person’s breathing (ventilation) and pulmonary function, in terms of potential lung disease and/or the condition of the muscles involved in breathing. Muscles of breathing-skeletal muscles-diaphragm and inter-costal muscles. Basic understanding that the cylinder/piston inside the spirometer rises based on volume of air inspired with regular effort vs maximal effort. Fundamental concept of the lungs having significant extra/back up capacity for air/oxygen for situations in which we need more air/oxygen (and ability to compensate if part of a person's doesn't lungs are removed or not functioning). 1. Oxygen Saturation/Pulse Oximetry: a. pulse oximetry: it measures 2 physiologic parameters-oxygen saturation-based on percentage of all the binding sites for oxygen molecules in all the hemoglobin molecules which are occupied by/saturated with oxygen molecules/all the iron atoms in the hemoglobin molecules in RBC’s. Oxygen binds to hemoglobin/specifically to the iron atoms in the hemoglobin molecules. i. It also measures Heart Rate (which is related to oxygen delivery to the tissues).  6 1. Basic exercise of placing finger in pulse oximeter, with Oxygen saturation reading in percent, and heart rate. (Normal O2 saturation of mid to high 90’s) 2. Exercise-increase in respiratory rate, in addition to increased heart rate, to increase oxygen content in blood and maintain oxygen saturation (therefore, the saturation remains constant which you might not expect). 1. Blood Typing/Hematocrit-centrifuge: concept of hematocrit-percentage/fraction of whole blood comprised/made up of red blood cells. blood consisting of cells and plasma with red blood cells being the most numerous cell type. a. centrifuge-spin blood in a machine and based on gravitational forces the heavier/denser red blood cells settle at the bottom with the plasma on top. By looking at the full height of the column of blood, including blood cells and plasma, one measures the percentage/fraction composed of/made up of just the red blood cells. i. Anemia-deficiency of RBC’s and, therefore, decreased oxygen transport to tissues. Hematocrit is one way to evaluate for anemia. The most common cause of anemia is iron deficiency. b. Blood typing-A, B, AB, O- blood types, having certain molecules/antigens on the surface of one's red blood cells. A type has A type molecules/antigens on RBC surface, B has B type; AB has both A and B; O has neither A nor B.Also, Type A blood individuals naturally have anti-B antibodies; Type B has anti-A antibodies; Type AB has neither; type O has both anti-A and anti-B antibodies. c. Transfusions involving a donor and a recipient need to match so that the recipient’s immune system doesn’t attack the donor blood because of recognizing the donor blood as foreign. Please review the blood types and what types of blood each can safely receive, like type A can receive A and O, but not B or AB, and the reasons why. - Type A can receive from Types, A, O - Type B can receive from Types, B, O - Type AB can receive from Types, A, B, AB, O - Type O can receive from Type O In addition, re: the Rh molecule/antigen; someone who is Rh+ has the molecule/antigen on the surface of the RBC’s; someone Rh- does not. No natural Rh antibodies are present, but a person who is Rh- and is given Rh+ blood will recognize it as foreign and attack the blood. For example, a person who is A- cannot be given A+ blood.  7 ○ Using synthetic blood and blood typing slides with wells, in which a drop of blood is placed in each well, and then anti A, anti B, and anti Rh antibodies were added to determine the blood type, based on antibodies reacting with the blood and causing clumping (agglutination). (If anti B clumps, must have B antigen etc.) 1. Urinalysis: evaluating/testing a person's urine for: a. Physical characteristics, like color-yellow; red would indicate the presence of blood-hematuria, which would be gross hematuria vs microscopic hematuria visualized through a microscope; is the urine clear; and specific gravity (discussed below). b. Chemical characteristics, like pH, presence of protein, presence of glucose. c. Microscopic characteristics, like presence of RBC’s-microscopic hematuria, or white blood cells indicating urinary tract infection. - glucose-normally glucose is not present in urine(except for very small amounts) ; its presence could indicate that the person has diabetes. - protein-also not normally present in urine (except very small amounts); its presence could indicate kidney disease. - pH of urine (it can normally range b/w acidic and slightly basic, 6-8). specific gravity-density/concentration of urine based on solutes dissolved in it, and if substances are in urine which shouldn’t be (like glucose or proteins) or excess solutes are present, the specific gravity would increase. Excess solutes (other than glucose or proteins) reflected in an increase in specific gravity could occur in dehydration, which reflects the kidney’s ability to concentrate urine and allow the body to keep more water. ○ for glucose, protein, and pH we used specific dip sticks which would show a color change if glucose/protein were present, and the specific pH would cause a 'color' change, which would be reflected in the color scale for different pH ranges  8 ○ For specific gravity we used a hydrometer with a floating measuring tube/gauge. The greater the density, the higher the specific gravity, the more the hydrometer tube floats in the urine sample/solution. The one that is less dense will float. The solution is the urine. The hydrometer has a fixed density. If there are things in the urine that aren’t supposed to be there, or its too concentrated because of dehydration, the gravity will be higher 1. CPR: cardio-pulmonary resuscitation if heart and breathing stop/cardiac arrest; basic protocol: A. Ensure safety of environment (for yourself and person/patient) B. Assess if a person is conscious/responsive by trying to physically stimulate him/her and asking, 'are you ok?' C. Ask someone else to call 911, or call yourself, if no one else is available D. look for signs of breathing and feel for a pulse (both at the same time) for no more than 5-10 seconds E. if no pulse and no breathing, follow the protocol of CAB. a. Previously, the protocol was ABC-airway, breathing, circulation/compressions. It changed because the benefit of circulation/compressions of blood with some oxygen still in it (from the last time the person breathed) is greater, rather than time spent first on airway and breathing. C A B; C-circulation- by performing compressions in center of chest with both hands over sternum interlaced (above the xiphoid process which is at the bottom edge of sternum) with rate of 100-120 compressions per minute, and compressions should be not too deep and not too shallow (about 2-2 1/2 inches deep) using whole body/shoulders as a force-not the hands or arms. A-airway-to open the airway by lifting the chin and tilting the head back B-breathing-providing breaths of air, let's say by using an oxygen/air bag-mask; the pattern would be 30 compressions followed by 2 breaths, followed by 30 compressions then 2 breaths…. Article summaries: 1. 'A Speech Neuroprosthesis in the Frontal Lobe and Hippocampus: Decoding High-Frequency Activity into Phoenemes'; Neurosurgery; Tankus, Ariel, et al. May 2022. The article presents clinical research regarding individuals who have a loss of speech (due to stroke, ALS, or other brain injuries). The study is potentially relevant for individuals who lose  9 the ability to vocalize/articulate words/thoughts but still have the ability to formulate ideas/thoughts. The study involved placing electrodes in a patient who was being treated for a different condition (epilepsy). He first vocalized certain basic sounds of speech, allowing the computer to identify the specific neurons which were responsible for those sounds through signals/action potentials generated from them. Then the patient formulated the same sounds in his mind/thought but did not vocalize them, and the computer translated/converted the thought signals into vocalized speech. (The term 'speech neuroprosthesis' refers to an artificial method/device of neurologic function) In essence, the computer was able to verbalize the patient's thoughts, by interpreting signals from specific neurons. 2. 'Physiologic Homeostasis after Pig-to-Human Kidney xenotransplantation'; Kidney International; Judd, Eric, et al. May 2024. The abstract from the article summarizes the clinical study regarding the potential for pig kidneys (a form of xenotransplantation from a different species) to substitute for human kidneys in individuals who don't have functioning kidneys. Due to a shortage of human kidneys available for transplant, pig kidneys could fill a significant need. The individual in whom pig kidneys were transplanted was someone who experienced brain death-irreversible cessation of all brain function, including the brain stem. The person's kidneys were removed and replaced by transplanting two pig kidneys (the issue of transplant rejection, immunosuppressant medications, and genetic editing of the pig kidneys are important details but not on the exam). The patient's kidney function was monitored for 7 days. During that time, the kidney function of the transplanted pig kidneys increased, as evidenced by a decrease in the volume of urine output/urine production, since functioning kidneys must be able to produce concentrated urine and not excessive volumes, which would not be compatible with life sustaining homeostasis. Longer term studies would be a next step in the research. Sheep Heart Structures: right atrium, right ventricle, left atrium, left ventricle, pulmonary trunk, aorta, superior vena cava - https://www.youtube.com/watch?v=HNxSC244Bpo Exam Practice Questions: 1. A pulse oximeter measures a. Heart rate  10 b. Tidal volume c. Oxygen saturation d. A and C e. All of the above 2. A patient has a hematocrit of 20 (below normal, usually supposed to be 40). You would explain to him that… a. 20% of blood cells are red blood cells b. 20% of all the blood are red blood cells c. 20% of oxygen binding site are occupied d. 20% of red blood cells transporting oxygen 3. A person with blood type B- can receive a transfusion from a donor with blood type a. B+ b. A- c. O- d. None of the above 4. An EKG a. Can be used to measure heart rate b. Represents electrical activity c. Evaluates heart rhythm and patterns d. All of the above 5. The volume of air which cannot be exhaled is a. Inspiratory reserve volume b. Residual volume c. Tidal volume d. None of the above