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6 Start with Why How Great Leaders Inspire Everyone to Take Action - Explains the importance of developing a shared philosophy for business, teams, and frankly, any mission. It relays a vital concept, but the text is unnecessarily repetitive- it could be significantly shorter while maintaining the message. - Regarding a business model- your "why" is your basic underlying philosophy, motivation, and guiding principle, your "how" is your process, and your "what" is your product. - You can convince customers to buy your newest product, but you have to re-create your marketing with each novel concept. Loyal customers buy your product because they believe in your philosophy. Think about Apple. They don't sell a product. Apple customers will purchase the next Apple product, not because of the particular design or nuanced update, but because they believe Apple's "why." - Ask an employee or a teammate- what do you do? Is their answer a description of their daily tasks? Or is it a message, a principle that guides their action? - If your company's "what" becomes obsolete, your company becomes outdated. If your company was created to copy written text manually, you would be unlikely to adapt to the new technology that successfully automates the process. If your company's "why" was focused on the value of literature and facilitating easy access to books for everyone, this will allow you to remain relevant regardless of how the world changes. Previous Next

< Back Vent Mgmt #1: Basics The goal of ventilatory support is to maintain appropriate O2 and CO2 in the blood while offloading the work of the respiratory muscles and minimizing iatrogenic lung damage. Understanding this principle will help guide your ventilator management. Many variables can be manipulated on the ventilator, but there are a few key variables that truly control oxygenation and ventilation. While there is not one ideal setting for every scenario, there are a few basic principles that cover the majority of ventilator management. Basic Ventilator Settings First, it is important to understand what the ventilator does. The ventilator can push air into patients. You can control how much air is pushed in (tidal volume), the number of breaths per minute (respiratory rate, RR), and the concentration of oxygen molecules in the air itself (fraction of inspired oxygen, FiO2). It's also possible to control how quickly air is pushed in (flow)- but we will get to that later. It is important to note: the ventilator does NOT generate pressure- it only monitors pressure to prevent damage from elevated pressures (barotrauma). Breathing is controlled by three variables. Trigger- this determines when a breath starts. Either time, flow, or pressure. Time trigger is utilized when the patient is not generating any spontaneous breathing (ie mandatory breaths). Flow and pressure triggers are utilized if the patient has spontaneous respiratory activity. When the patient attempts to inhale, there is a change in flow and/ or pressure. This is sensed by the ventilator, and a breath is delivered. Limit- this sets the maximum value a parameter can reach during a breath. For example, volume-limited indicates that a breath can't exceed a certain max mL and pressure-limited indicates that the pressure monitored by the machine can't exceed a certain max cm H2O. For a graphic representation, please refer to the image in the section on Limit Variables in Deranged Physiology. Limits impact the shape of the waveform. Volume limited- flow ceases when the set/ target volume is delivered. Pressure limited- a large portion of the TV delivered at the beginning of the breath until the set/ target pressure is reached and then the flow tapers, slowly delivering the remainder of the volume until the breath is time or flow cycled (see next) Cycle- this determines the end of a breath. Time cycled- inspiration ceases at the end of a set time duration. Used in mandatory breaths. Flow cycled- inspiration ceases when flow drops below a certain level. Used in spontaneous breaths. Volume and pressure are not currently used to cycle breaths. The goals of mechanical ventilatory support are O2 delivery (oxygenation) and CO2 removal (ventilation). Effective oxygenation and ventilation are measured by an arterial blood gas- PaO2 indicates the partial pressure of O2 and PaCO2 indicates the partial pressure of CO2. Oxygenation is a function of the concentration of O2 delivered to the patient (fraction of inspired O2, FiO2) and the surface available for O2 exchange. Positive pressure maintains open airways, which maintains the surface available for O2 exchange. Mean airway pressure (MAP) is the parameter that indicates the average pressure measured in the lungs throughout inspiration (inspiratory pressure) and expiration (positive end expiratory pressure, PEEP). Expiration is usually 2-3 times longer than inspiration, so MAP is often simplified to PEEP when trying to optimize oxygenation. However, increasing inspiratory time can improve MAP without adjusting PEEP. Ventilation is controlled by minute ventilation (total volume of air exchanged every minute). Minute ventilation is respiratory rate multiplied by tidal volume. Therefore, respiratory rate (RR) and tidal volume (TV) are the two parameters that can optimize ventilation. Lung-Protective Ventilation Minimizing iatrogenic lung injury is also important when caring for patients receiving ventilatory support. Different types of trauma, including barotrauma (excess pressure), volutrauma (excess volume), and atelectrauma (repetitive opening and closing of alveoli), can damage lungs that are already diseased. The risk of barotrauma can be minimized by monitoring airway pressures (peak and plateau pressures). Volutrauma can be minimized by low tidal volume. Historically, larger tidal volumes were standard (10-12 mL/kg). Currently, the most commonly recommended volume is 6-8 mL/kg (there are some exceptions). Decreased TV leads to ↓minute ventilation and ↓CO2 clearance (↑PaCO2). This is the basic physiologic principle behind "permissive hypercapnia" during mechanical ventilation for ARDS. Atelectrauma can be minimized by maintaining PEEP, which keeps alveoli open. Additional References 1. Respiratory Therapy Pocket Reference Card Previous Next

5 Critical Care References ICU Rounds A-F Bundle .pdf Download PDF • 33KB Pharmacology Med Doses .pdf Download PDF • 56KB Neurologic RASS .pdf Download PDF • 281KB CAM-ICU .pdf Download PDF • 127KB CPOT .pdf Download PDF • 76KB EtOH Withdrawal .pdf Download PDF • 1.02MB Cardiac Arrhythmias .pdf Download PDF • 1.55MB Pulmonary Cuff Leak .pdf Download PDF • 15KB Fluids, Electrolytes and Nutrition Fluids .pdf Download PDF • 29KB Na and pH .pdf Download PDF • 53KB Endocrine and Nutrition Types of Insulin .pdf Download PDF • 85KB TPN .pdf Download PDF • 221KB Steroids .pdf Download PDF • 36KB Hematology Anticoag .pdf Download PDF • 44KB Anticoag Reversal .pdf Download PDF • 334KB Organ Donation Hormone Therapy .pdf Download PDF • 13KB

How to play nice in the sand box...and why it matters Consults < Back How to play nice in the sand box...and why it matters The department of Acute Care Surgery and Emergency Medicine frequently interact to discuss consults. Unfortunately, several factors predispose to an adversarial relationship between the ER provider and the consultant.(1) I won't pretend that I didn't contribute to some of the negative interactions I've had while responding to consults. However, I'm grateful that my years of experience have provided me with insight and perspective that reframed my thoughts about the consultation process. What are the different types of consults? #1 The patient requires something that is beyond the scope of practice of the emergency provider. This includes everything from hospital admission, surgical or procedural intervention (appendectomy, stop the bleeding from a penetrating neck wound, cardiac catheterization), or a plan for close follow-up. How to Respond? This is why we chose our specialty, and our business is patient care. If a consultant is not responsive, it might be because they are caring for more urgent clinical issues. It's also possible that they are a generally unpleasant person, and it has no relation to the nature of the consult..some people can be difficult regardless of the scenario. Admittedly, it might also be 2 am, and they just fell back asleep after their last page. As much as I hate to admit, it's harder to be pleasant on the phone when you're absolutely exhausted. #2 The unclear diagnosis. The patient is presenting with a complex issue, or the diagnosis may be outside the provider's experience. This could be the first time they encounter a particular clinical scenario or an unusual presentation of a common diagnosis. How to Respond? Depends on the scenario. If that patient requires emergent assistance, prioritize their needs. If no emergent need, but further workup is needed, provide whatever recommendations you can regarding the next steps of the diagnostic workup. If the patient's case falls under your specialty, refer back to #1. #3 The emergency room provider doesn't know who the appropriate consultant is, or they have had no luck reaching them. How to Respond? It's easy to brush off a call when the primary provider called the wrong service. This might occur if the provider cannot reach a particular specialist, and you are the next best option (example- plastic surgeon doesn't respond for a consult on a patient with a wound complication). Please, if you know how to reach that provider, lend a hand. Or, if they call the wrong service, take the time to give a little guidance about whom they should have called. They aren't trying to waste your time- they are likely also busy, and calling multiple consultants is not the best way to spend their time either. Whatever assistance you can provide is best for the patient. #4 The controversial consult. In my experience, during years of working with surgeons and emergency physicians, probably one of the most contentious consultations is the consultation for something that the consultant considers inappropriately simple or unnecessary. The surgeon may think that the issue is trivial or the need is non-existent and feel that the provider should be capable of resolving the issue without calling a surgeon. This disconnect might be the key patient interaction that can set the tone for the relationship between departments. How to Respond? First, and most importantly, please don't be dismissive when someone calls you for a consult. If you are receiving a call, it's because the person on the other end of the phone (and therefore the patient they are caring for) needs your help. Surgeons, along with other specialists, have extensive specific expertise, so it's easy to lose perspective and presume that the knowledge in our head is universal. It's become almost intuitive in our minds, so we might forget that the primary provider does NOT have the same specialization. We each chose our respective specialties, and our training and biases are quite divergent. It is unreasonable to expect ER physicians to share the same depth of knowledge in each of the many specialties, just as each of the specialists would not have the same ability to deftly juggle the wide array of clinical scenarios managed in the ER. I remember the plastic surgeon who showed me how to do a scar revision on a young woman's face. He spent his career training and practicing to perform plastic surgery. It was simple in his hands, but that doesn't mean the woman would have a similar outcome if the needle driver was in my hand. Please, think of the patient's best interest. Yes, the primary provider may be "an idiot" or "lazy" or whatever. But consider the other possibilities. I prefer to give my colleagues the benefit of the doubt and avoid automatically assuming incompetence. Regardless of the underlying issue, whether it's a flaw of the provider or its truly beyond their capability, the patient needs someone to take care of them. Do the right thing for the patient- in the end, that's what matters. 1. Koo A, Bothwell J. Tips for Working with Consultants. ACEP Now. Nov 2017. Previous Next

Favorite Websites and Apps < Back Kitchen Hacks #4 Favorite Websites and Apps How Sweet Eats Eating Well (previously Cooking Light) Cooking Substitutions Previous Next

< Back GERD What is GERD? Gastroesophageal Reflux Disease (GERD), more commonly known as heartburn, is caused by acid from the stomach moving into the esophagus, which causes a burning pain in the middle of the chest. Anatomy After swallowing, food moves down the esophagus and into the stomach. The lower esophageal sphincter (LES), which is at the connection between the esophagus and stomach, prevents stomach contents from moving back into the esophagus. The lower esophageal sphincter is located below the diaphragm, where pressure from the abdominal organs helps keep the sphincter closed. There are different causes of GERD, but the lower esophageal sphincter is key to preventing reflux. See below for more details about why GERD occurs. Source: UpToDate Images: Gastroesophageal Reflux (GERD) Causes of GERD Decreased pressure of the lower esophageal sphincter- if the lower esophageal sphincter is too loose/ relaxed, stomach contents move more easily into the esophagus. This can be a pre-existing condition but it can also be caused or worsened by lifestyle habits. For example, tobacco and certain foods such as alcohol, chocolate, caffeine, carbonation, mint, citrus/ tomato-based foods, spicy/ fried/ fatty foods, can also decrease the pressure of the sphincter. Eating too much/ too fast→ overfilling the stomach leads to increased pressure, causing stomach contents to be pushed into the esophagus Laying flat- when you are standing or sitting upright gravity helps avoid reflux by keeping food in the stomach, but when laying flat, stomach contents can move into the esophagus more easily. This is why symptoms are often more severe at night or first thing in the morning. Hiatal hernia - when the lower esophageal sphincter is able to move into the chest, it no longer has the external pressure normally present when it’s in it’s correct position, and it more easily allows stomach contents to move into the esophagus. See link for image. Obesity or pregnancy- increased pressure on the abdomen from excess weight can put pressure on the stomach and allows stomach contents to move into the esophagus for easily. GERD: Symptoms and Causes [Mayo Clinic: Patient Care & Health Information] Diagnosis Symptoms are often adequate to diagnosis GERD. A swallow study can provide further information. This study is performed in radiology, and involves drinking contrast material and having x-ray images taken to evaluate the esophagus and stomach while you swallow. This study can diagnose esophageal problems, such as poor muscle function leading to swallowing difficulty. In addition, a hiatal hernia can be identified. John Hopkins Medicine: Barium Swallow An esophagogastroduodenoscopy (EGD), also known as an upper endoscopy (see link) can be used to assess the inner lining of the esophagus, stomach and the first part of the small intestine (duodenum). There are many things that can be identified on an EGD, but specifically related to GERD, damage to the lining of the esophagus and the presence of a hiatal hernia can be identified with an EGD. Patient education: Upper endoscopy (Beyond the Basics) [UpToDate] Upper Endoscopy [Society of American Gastrointestinal and Endoscopic Surgeons (SAGES)] Additional testing can be performed based on symptoms, results of initial testing and response to treatment. Esophageal manometry- a study to evaluate the muscle function of the esophagus ( pH test- a study to evaluate how much acid the esophagus is exposed to, which is one measure of the severity of GERD. GERD: Diagnosis and Treatment [Mayo Clinic: Patient Care & Health Information] Treatment Lifestyle Modifications [ Patient Handout: Anti-Reflux Diet and Lifestyle Modifications ] Eat slowly, avoid eating large meals and stop eating before you feel full. Avoiding alcohol, chocolate, caffeine, carbonation, mint, citrus/ tomato-based foods, spicy/ fried/ fatty foods. Avoid lying down for at least 2-3 hours after meals. Don't snack after dinner/ before bed. Elevating the head of the bed by 6-8 inches. This is NOT done by placing multiple pillows under your head- multiple pillows would actually increase pressure in the abdomen (like doing a sit-up or crunch). For more information, see this guide from the Kingsley clinic. Lose weight. Stop smoking. Avoid tight-fitting clothing. Medication Over the counter antacids Prescription medication Surgery Depending on how well medication and lifestyle modifications improve your GERD symptoms, and depending on the results of your other studies, such as your swallow study, esophageal manometry and pH testing, surgery may be an option for GERD. UpToDate Patient Education Patient Education: Gastroesophageal reflux disease in adults (Beyond the Basics) Previous Next

12 Barking Up The Wrong Tree The Surprising Science Behind Why Everything You Know About Success Is (Mostly) Wrong - Good grades in school- likely to be a "rule follower", and less likely to be innovative, think outside the box. - Introverts are more likely to be experts, extroverts tend to make more money (socializing, "networking"). We should look at "networking" as "making friends". This disputes the "nice guys finish last"... - Match your strengths/ passion/ skill to the right context. - Flattery (sucking up to the boss) can work in the short term, but in the end, when people see their colleagues/ neighbors/ etc cutting corners and reaping benefits, this leads to a general collapse into distrust and rule-breaking. - IQ only matters up to a certain point, but then it yields diminishing returns. After that, hard work is what makes the difference. - Tradeoffs- every hour that you spend working is an hour spent away from other things (family, hobbies). In this age of constant accessibility, you have to decide to leave work behind (ignore your emails when you're at your kid's ball game). - Gratitude in relationships- on their deathbed, people regret working too much and not saying thanks to the people in their life. - Some helpful things I learned...please note that tact and delivery matter and these are not appropriate in every scenario. - When someone is getting upset or frustrated and starts yelling, "Please speak more slowly, I want to help." Or try, "What would you like me to do?" - When someone is upset, validate/ name their feeling. "Sounds like you’re angry/ hurt/ frustrated." If you're wrong, give them the chance to correct you. - Gratitude to relationships. Previous Next

How not to lose everything < Back Organizational Hacks How not to lose everything All my life, I've been forgetful and easily distractible. I joke that I'd lose my head if it wasn't attached. This challenge is part of my ADHD, and I can't overcome it with sheer willpower. The list of things that I've lost over the years is staggering- homework (oh so much homework…it was usually stuffed somewhere in my locker), clothing, books, charging cables, water bottles, earrings (what am I supposed to do with the remaining single earrings?) and a white polar bear stuffed animal (he was left in a hotel room on a road trip as a child). I'm looking forward to learning where all my things went when I die and go to heaven. So if this can’t be overcome with sheer willpower, how can you adapt? Check out these techniques or tools to see if you find something that would be useful for yourself. Information * Create a tool for yourself for storing the data you need to be able to access reliably. This website is full of high-yield medical information that is rapidly accessible, but a website is a labor-intensive option. You don’t have to invest time and money into a website. Here are some other options (check out this post for more details ): - Invest in a planner . Electronic options that sync are useful because they minimize the need to re-write things in multiple places. Another option that I prefer is one notebook that keeps all my events in one place, along with my collection of lists and reminders. - Write everything down. My planner is my note repository. The Apple Notes application is also useful because it can sync across multiple Apple devices. At home or work, dry-erase poster paper can be used to take notes, keep track of schedules and provide reminders for long-term tasks and due dates. - Trello is a user-friendly free application with multiple functions, including the creation of lists, storage of documents, and the ability to share notes or documents among team members/ family members. Items * Magnet strips . Using magnetic sheets the size of business cards, cut pieces and strips to put on various items and stick them to the fridge or other magnetic surface of your choice. For example, if you use dry-erase poster paper on the refrigerator, thin strips of magnet can be cut to fit along the length of several dry eraser markers, so they're always on hand when you have something to jot on the whiteboard * Keys on a hook by the front door. 3M hooks work well, but the hook design isn’t as important as placement, ideally not in direct sight of the door. You can also hang your work ID badge or any other small items you need when you leave the house. * Keep track of all your cords with these tie wraps . Inexpensive and sturdy. I didn’t think there was any way I’d use 50- I figured maybe a couple, just for a handful of my charging cables that always end up in a jumble. But trust me, you'll find plenty of uses for them! Finances and Important Documents * Save receipts for anything valuable. If it was purchased online, download the digital receipt. Use the "Create PDF" function to combine receipts. For paper receipts, an envelope in a drawer is a simple option. Every so often, review the receipts, and if there is anything you don't need anymore, toss it. * Paper shredder . Anything with personal information should be destroyed before being thrown away. This is technically not about avoiding losing something, but it’s an important task so it is included here. * Taxes. Instead of waiting until tax season, keep track of key documents and expenses throughout the year. A running spreadsheet of business expenses, donations, etc, can avoid the frantic search in March. * Metal rack of hanging file folders. Each folder has a different label, including taxes (donation receipts, investment statements, etc), moves (signed leases, welcome packet with key information, etc), and business (bank paperwork, original EIN and registration forms, deposited checks). Previous Next

11 Made to Stick Why Some Ideas Survive and Others Die 6 Principles of Sticky Ideas - Simple - Unexpected- crash at the end of the car commercial. - Concrete - Credibility- the ability to test. Before you vote ask yourself if you are better off today than you were 4 years ago- Reagan. - Emotions - Stories Curse of knowledge- we find it hard to imagine not knowing what we have learned. Can’t imagine what it’s like not to understand a certain concept that we accept as fact Previous Next

< Back Ultrasound: Cardiac Exam Purpose: identify possible causes of hemodynamic instability, respiratory distress, assessment of volume status. Probe The phased array can be used for the entire exam. The curvilinear can also be used for the subxiphoid and IVC views. Views There are 4 basic views, including the parasternal long axis, parasternal short axis, the apical four chamber and the subcostal view. Additionally, the inferior vena cava can be visualized. Cardiac ultrasound is more challenging to learn than most other ultrasound studies, because probe usage (position, angle, rotation, translation, etc) have drastic impact on visualization. It’s necessary to understand what is shown in each view, so take time reviewing these so you can have a better appreciation for what you are seeing when you perform a study on a real patient. One recommendation, if it is difficult to visualize the heart, moving the patient into the lateral decubitus with their left side down can significantly improve visualization as the heart is closer to the chest wall in this position. For video and pictorial explanations of the views, please refer to these sites. Basic Cardiac Views, #1 Basic Cardiac Views, #2 Findings Gross abnormalities- decreased ventricular function, arrhythmias Profound hypovolemia Small hyperdynamic left ventricle with end-systolic collapse Inferior vena cava- assess volume status, either static measurement of diameter or calculation of collapsibility (>50% correlates with volume responsiveness). Respiratory variation (collapsibility/distensibility index). Takotsubo cardiomyopathy Akinesia of the apical and mid-ventricular segment, hypercontractile basal segments. Apical sparing (dilated). Acute cor pulmonale Respiratory disorder→ pulmonary hypertension→ right heart failure. Dilated right heart. Cardiac tamponade Effusion with end-diastolic collapse of the right atrium, effusion in front of the aorta Pulmonary embolism Free-floating thrombus in the right ventricle or pulmonary artery; right ventricular dilation/ systolic dysfunction; septal bowing into the left ventricle; dilated IVC without inspiratory collapse. Most sensitive/ specific indirect sign- right ventricular apical sparing (McConnell's sign). References Guidelines for Performing a Comprehensive Transthoracic Echocardiographic Examination in Adults: Recommendations from the American Society of Echocardiography Previous Next

< Back Cardiac Physiology Cardiovascular Physiology Oxygen Delivery Adequate cardiovascular function is vital to maintaining perfusion to the organs and tissues in the body. Perfusion drives oxygen delivery (O2) and removal of byproducts of cell metabolism (CO2). The amount of oxygen that is delivered (DO2) is a function of cardiac output (CO; the volume of blood ejected from the heart every minute) and the arterial oxygen content (amount of oxygen in the blood). Cardiac output is determined by the volume of blood the heart pumps out into the body with each heartbeat (stroke volume, SV) and the frequency of the heartbeat (heart rate, HR). Stroke volume depends on preload (blood volume returned to the heart), contractility (effectiveness of cardiac muscle activity), and afterload (pressure in the peripheral vasculature that the heart has to overcome to eject blood). Arterial oxygen content (CaO2) is the amount of O2 in the blood that is ejected from the heart. This is determined by dissolved O2 + O2 bound to hemoglobin. Hemoglobin carries O2, and the percentage of Hgb molecules that are saturated (bound) with O2 is determined by arterial blood gas (SaO2, arterial oxygen concentration) or pulse oximetry (SpO2, peripheral arterial oxygen concentration). Pulse oximetry is non-invasive and is a reliable surrogate (as long as SaO2 >90%). The O2 carrying capacity of one gram of hemoglobin is 1.38 (this is a constant in the equation). So this is the first part of the equation: the number of hemoglobin molecules x the % of those molecules that are saturated with O2 x how much O2 saturated hemoglobin can carry . The second part of the equation is the dissolved oxygen (partial pressure of arterial oxygen, PaO2, reported as mmHg). This value is multiplied by the constant 0.003, which is the mL of O2 dissolved per mmHg plasma. This number is infinitesimally small relative to the other half of the equation and it is typically ignored when determining oxygen concentration. This means that the significant modifiable factor in CaO2 is Hgb. Oxygen has to have something to bind to (Hgb) because dissolved oxygen has minimal oxygen-carrying capacity. Oxygen delivery (DO2)= CO x CaO2 Cardiac Output (CO)= heart rate (HR) x SV Stroke volume (SV)= the volume of blood ejected from the heart each heartbeat. Arterial oxygen concentration (CaO2)= [1.38 x Hgb x SaO2] + [PaO2 x 0.003] How can oxygen delivery be increased? One of the components of the equation has to be adjusted. Increase cardiac output. Increase SV- use of an inotropic agent (* medication that increases the strength of the heart contraction), ensure adequate preload (volume resuscitation). Increase HR- use of a chronotropic agent (* medication that increases heart rate). Increase arterial oxygen content Increase blood hemoglobin concentration *See pharmacology below Oxygen Consumption Oxygen consumption (VO2) is determined by how much oxygen the peripheral tissues extract and use. It is the difference between oxygen delivery (DO2) and oxygen return(ed) (SvO2). Oxygen consumption (VO2)= DO2 - SvO2. Oxygen consumption is calculated by subtracting SvO2 or ScVO2 from the amount of oxygen delivered. Venous oxygen saturation (SvO2 or ScVO2)- concentration of oxygen in the blood returning to the heart. Measured with a central venous catheter. *See below under CV monitoring for more details. Cardiovascular Monitoring There are several techniques for monitoring cardiovascular parameters, ranging from non-invasive to maximally invasive. Non-invasive methods include telemetry, pulse oximetry, and blood pressure monitoring. The benefit of these devices is their simplicity of use and interpretation. But these are error-prone, and regarding blood pressure, it doesn't provide continuous monitoring. For more info, see lecture entitled " Hemodynamics ". Arterial lines can be placed to provide continuous cardiac monitoring. The arterial waveform can indicate specific pathology (see Edwards Quick Guide to Cardiovascular Care ). In addition, an arterial line can report stroke volume variation. Stroke volume variation (SVV) is a surrogate of arterial pressure changes with inspiration/ expiration. If the change in pressure with respiratory cycles is >10-15%, it suggests the patient is fluid responsive, meaning they are likely to improve their preload (and cardiac output and blood pressure) with IV fluid administration. Central venous catheters can be placed to deliver intravenous medication as well as provide cardiac monitoring. A central venous catheter can measure the pressure of the blood returned to the right atrium (central venous pressure, CVP), which is a crude measurement of preload and right heart function. In addition, the oxygenation of the blood returning to the right heart (from the head and upper body) is reported as Central venous oxygenation saturation (ScVO2). ScVO2 reflects the balance between oxygen delivery and consumption. Arterial lines and central venous catheters are considered "minimally invasive". A pulmonary artery (PA) catheter is the most invasive device for cardiac monitoring. Similar to a central venous catheter, a PA catheter can determine the oxygenation of the blood returning to the right heart, which is the mixed venous oxygen saturation (SvO2). However, in contrast to the central venous catheter which is located in the superior vena cava (proximal to the right atria), this device is measuring blood oxygenation in the pulmonary artery (from the right ventricle), so it accounts for the blood from the entire body (unlike the ScVO2). Cardiac Pharmacology Vasoactive medications are frequently used in the ICU for the management of shock, heart failure, and other acute pathology. There are several key receptors, and understanding the function of each receptor is the key to using these different agents correctly. Receptors * α (alpha) 1- vasoconstriction * α2- inhibit norepinephrine release from presynaptic neurons * β (beta) 1- chronotrope (↑HR), inotrope (↑Ca in cardiac myocytes ↑contractility), dromotrope (↑cardiac impulse conduction velocity) * β2- vasodilation * Dopa 1- vasodilation * Dopa 2- neurotransmitter release Pharmacologic Agent Classification Each medication has a specific physiologic effect based on its particular mechanism of action. Agents may stimulate or inhibit receptors (see above) or alter the concentration of a key substance (cAMP, calcium, potassium, nitric oxide (NO)). Previous Next

11 < Back Board Examinations American Board of Surgery: General Surgery Boards Exam Prep Master the General Surgery Oral Boards by Dr Hassan Aziz . Dr Aziz reviews key surgical topics, including trauma, thoracic, pediatric, HPB, GI, breast cancer, endocrine, vascular. [Reference courtesy of Hassan Aziz, MD @Sharpknife_Aziz ] Surgical Education and Self-Assessment Program (SESAP). Resource for general surgeons- stay current with the latest surgical knowledge and prepare for examinations. American Board of Surgery: Surgical Critical Care Boards Exam Prep Evidence-Based Practice of Critical Care. 3rd edition, 2019. Reviews the literature regarding specific high yield critical care topics. Trauma, Critical Care, and Surgical Emergencies: A Case and Evidence-Based Textbook. 1st edition, 2010. 64 cases that review the basic principles of ACS. Previous Next