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< 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

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

2 < Back Operating General Surgery Texts Chassin's Operative Strategy in General Surgery: An Expositive Atlas. 5th Edition, 2022. Zollinger's Atlas of Surgical Operations. 11th Edition, 2021. Operative Dictations in General and Vascular Surgery. 2012. Acute Care Surgery Texts Operative Techniques and Recent Advances in Acute Care and Emergency Surgery (Aseni). 1st edition, 2019. Surgical Decision Making in Acute Care Surgery. Atlas of Trauma/Emergency Surgical Techniques. Top Knife (Mattox). 1st edition, 2004. High yield of trauma operative management. Back to the basics. Atlas of Surgical Techniques in Trauma (Demetriades). 2nd edition, 2020. Anatomic Exposures in Vascular Surgery (Wind). 3rd edition, 2013. Key anatomic exposures for less commonly encountered injury patterns. Recommended by Dr. Feliciano at AAST 2020 Conference. Videos Surgical Stabilization of Rib Fractures and Cryoablation. Collection of videos of different surgical approaches. WebSurg. Free access to expert videos of minimally invasive surgery. Highly recommend. The Toronto Video Atlas of Surgery. Free access to expert videos of GI operative procedures. [Reference courtesy of EJS @ElliotJScottMD] Difficult Cholecystectomy: A learning module for laparoscopic cholecystectomy How to Tie Knots Like a Heart Surgeon How to Secure Chest Tubes (Soweto Tie) Previous Next

5 < Back Critical Care Resources Society Guidelines CHEST Guidelines. Topics addressed include: Acute Respiratory Distress Syndrome (ARDS), venous thromboembolism (VTE), and liberation from mechanical ventilation. Antithrombotic Therapy for VTE Disease: Executive Summary (2021) SCCM Guidelines. Topics addressed include: Surviving Sepsis, management of pain/ agitation/ delirium, nutrition, critical-illness-related corticosteroid insufficiency, etc. Infectious Disease Society of America. Critical Care Nutrition. Nutrition guidelines and bedside tools (i.e., Nutric score). European Society for Clinical Nutrition and Metabolism (ESPEN). References ICU One Pager. "Critical care education one page at a time. Simple, free, & open source." High-yield clinical topics condensed into single-page reference cards. Other topics addressed in more detail include point of care ultrasound (POCUS) and COVID. The Bottom Line. High-yield journal article summaries focused on the diagnosis and management of critically ill patients. Critical Care Reviews Newsletter. Weekly update on the most up-to-date literature. Register to receive the email weekly. Life in the Fast Lane [LIFTL]. ICU providers provide educational resources for EM and critical care, including EKG interpretation and the Critical Care Compendium. REBEL EM. Journal reviews, tutorials, and other educational tools. Focus is emergency medicine, but plenty of cross-over with critical care. Stanford Critical Care Educational Resources. Free education resources hosted by Stanford Medical School. University of Maryland- Critical Care Project. Critical Care Now. Deranged Physiology. Antibiotic Coverage Diagram [image] EM-Crit Project. Parent website of the Internet Book of Critical Care and PulmCrit. The Internet Book of Critical Care (IBCC) PulmCrit - blog entries on practical ICU topics. Venous thromboembolism and anticoagulation management Anticoagulation Provider Toolkit Anticoagulation Desktop Reference Anticoagulation in Non-valvular Atrial Fibrillation Anticoagulation in Venous Thromboembolism DOAC Bleeding Management Anticoagulation in Pediatric Venous Thromboembolism Periprocedural Management (DOAC) Periprocedural Management (Warfarin) Cardio Nerds Infographics A Guide to Temporary Mechanical Circulatory Support in Cardiogenic Shock Inotropes Pulmonary Embolism Management Anticoagulation for Atrial Fibrillation/Flutter Push-dose vasopressors Push Dose Pressors: Your Quick & Dirty Guide emDOCs: Push-Dose Vasopressors: An Update for 2019 Scott Weingart: Push-dose pressors for immediate blood pressure control Tutorials Edwards Science Clinical Education. Free access to clinical resources including quick references for hemodynamic monitoring and oxygenation assessment of the critically ill. Quick Guide to Cardiopulmonary Care. Hemodynamic Optimization. Perioperative Goal-Directed Therapy. ScVO2 Monitoring. Thromboelastography. Diagrams of TEG and ROTEM, explanation of methods and variables. Previous Next

1 < Back Textbooks General Surgery: Scientific Foundations Sabiston Textbook of Surgery: The Biological Basis of Modern Surgical Practice. 21st Edition, 2021. This is the detailed explanation of the science behind the practice of surgery. This is the basic science textbook I used during residency. Mulholland and Greenfield's Surgery: Scientific Principles & Practice. Previously known as "Greenfields". General Surgery: Beyond Basic Science Cameron's Current Surgical Therapy. 13th edition, 2019. Short chapters with high-yield information on every topic in General Surgery. Must-have for later in residency. Trauma Mattox Trauma. 9th edition, 2021. The trauma surgery bible. Highly recommend. Critical Care Marino ICU. 4th edition, 2013. The ICU bible. Highly recommend. Civetta, Taylor, & Kirby's Critical Care Medicine. 5th edition, 2017. A detailed explanation of physiology, diagnosis, and management. Finks Critical Care. 7th edition, 2017. Slightly less detailed than Civetta. Excellent book- not too simplistic and not painfully detailed. Evidence-Based Practice of Critical Care. 3rd edition, 2019. Reviews the literature regarding specific high yield critical care topics. Surgical Critical Care Therapy: A Clinically Oriented Practical Approach. 1st edition, 2018. Essentials of Mechanical Ventilation. 4th edition, 2018. Previous Next

< Back Pre-Peritoneal Packing When: blunt pelvic trauma with hemodynamic instability. How: 1. Low vertical midline incision, stop a short distance below the umbilicus. 2. Split rectus, retract laterally, the peritoneum is just behind the rectus. 3. Slide hand directly under the rectus- palm toward peritoneum and back of your hand toward rectus. Bluntly dissect laterally toward ASIS. 4. Retract rectus anteriorly, use your other hand to place rolled laps in the potential space you just developed [This how-to guide was designed in response to a query from @obcast ] References Smith WR et al. Retroperitoneal packing as a resuscitation technique for hemodynamically unstable patients with pelvic fractures: report of two representative cases and a description of technique. J Trauma. 2005 Dec;59(6):1510-4 Filiberto DM and Fox AD. Preperitoneal pelvic packing: Technique and outcomes. Int J Surg. 2016 Sep;33(Pt B):222-224. Previous Next

Critical Care Medicine. Trauma Surgery. Evidence-based medicine. Doc on the Run. Medical Literature. Welcome to Doc on the Run! A look into the life and mind of an Acute Care Surgeon Sharing the knowledge and wisdom gained after 38 years of life (and over 20 years in medicine). For those who want to learn about the specialty of Acute Care Surgery , you will find insight into the profession, both from personal experiences and citations from articles and websites. For those interested in the medical profession, particularly surgery, you will find career management tips , including networking and mentorship . For learners (students, residents, fellows), you will discover a wide array of educational resources, including recommended educational resources , tutorials on a multitude of topics, a collection of didactic lectures and quick reference guides , an ever-growing library of literature reviews , and clinical vignettes . For fellow Acute Care Surgeons, please consider collaborating and sharing your experience and wisdom with the next generation. For the bibliophiles, check out the constantly expanding list of book recommendations .

< Back Shot in the Chest- Aortic Occlusion A 30-year-old male sustained a gunshot wound to his left lower chest/ upper abdomen. On arrival, his heart rate was in the 50s with weakly palpable carotid and femoral pulses. Significantly hypotensive. Penetrating wound to the left lower chest wall with an occlusive dressing in place without ongoing hemorrhage. Initial workup and management? Assess mental status. Secure large-bore peripheral IV access and start massive transfusion. A rapid ultrasound of the chest and abdomen revealed fluid in the left chest, right upper quadrant, and no pericardial fluid. We placed a left chest tube with minimal output. Still hypotensive…treatment options? Resuscitative thoracotomy. Urgent OR if vitals improve with resuscitation. REBOA. A rapid secondary survey revealed a previous midline laparotomy. This would likely impede rapid access for aortic control during laparotomy, so REBOA was placed through a right femoral artery cutdown. With inflation of the REBOA, he had a return of cerebral perfusion with spontaneous movement of his extremities. He was transported emergently to the OR. We encountered massive hemoperitoneum and extensive dense intra-abdominal adhesions that prohibited easy access for a supra-celiac aortic clamp. There was ongoing hemorrhage despite REBOA. Other options to control intra-abdominal bleeding? Procedures directed at source (compression of the liver, splenectomy, etc). Aortic occlusion above the injury- stops all perfusion below the level of occlusion. This can be done from the chest through a left anterolateral thoracotomy or below the diaphragm (supra-celiac clamp). The patient underwent left thoracotomy for aortic cross-clamp. There were no obvious intra-thoracic injuries. Intra-abdominal injuries included a large Zone 1 retroperitoneal hematoma and left diaphragm injury, injuries to solid organs (liver and pancreas) and hollow viscus (stomach, small bowel, and colon). Management of massive sub-diaphragmatic hemorrhage Aortic occlusion decreases distal bleeding and redistributes blood volume to the myocardium and brain. This leads to a reduction in sub-diaphragmatic blood loss. Traditionally, this is accomplished through an open approach, either via thoracotomy or laparotomy. Concurrent with the expanding use of and comfort with endovascular approaches, endovascular occlusion of the aorta (REBOA) has been re-introduced as a less invasive approach. General indications Traumatic life-threatening hemorrhage below the diaphragm (non-compressible torso trauma) in patients in unresponsive shock Zone 1 (distal thoracic aorta)- control of severe intra-abdominal/ retroperitoneal hemorrhage, or for traumatic arrest. Zone 3 (above aortic bifurcation)- severe pelvic, junctional, or proximal lower extremity hemorrhage. Mixed results regarding clinical outcomes. Essentially the same time to aortic occlusion as resuscitative thoracotomy. Not shown to be significantly quicker at obtaining aortic occlusion than resuscitative thoracotomy. Brenner M et al. Joint statement from the American College of Surgeons Committee on Trauma (ACS COT) and the American College of Emergency Physicians (ACEP) regarding the clinical use of Resuscitative Endovascular Balloon Occlusion of the Aorta (REBOA). Trauma Surg Acute Care Open. 2018;3(1):1-3. Previous Next