Kelly K. Hunt, MD

• Professor
• Department of Surgical Oncology
• The University of Texas
• MD Anderson Cancer Center
• Houston, Texas

For example alternative for antibiotics for sinus infection buy cephalexin online now, if a serving of food has 3 g of fat and the Daily Value for total fat is 65 g medicine for uti that turns pee orange order cephalexin 250 mg with visa, then the % Daily Value is 5% (3/65 = 0 antibiotic 33 x discount cephalexin 500mg with visa. Manufacturers will also be required to list the amount of added sugar on the nutrition label antimicrobial zinc gel discount cephalexin 500mg online, to assist the consumer in making better choices about total sugar intake antibiotic resistance zoology to the rescue order cephalexin 250mg on-line, which has been linked to the current increase in obesity in the United States antibiotics drinking buy on line cephalexin. Saturated fat and trans fat information will also be included, but the "Calories from Fat" on the old label will no longer be included. This reflects the modern view of nutritionists that the types of fats we ingest are more important than the amount. Once the new food label has been approved, manufacturers will have to include the revisions on most packaged foods within two years. After reading this section, you should be able to One serving of a food has 30 g of carbohydrate. The % Daily Values for nutrients related to energy consumption are based on a 2000 kcal/day diet. Describe the basic steps involved in using lipids and amino acids as energy sources. P Catabolism Catabolism is the energyreleasing process by which larger molecules are broken down to smaller ones. It consists of catabolism (katabo-lizm), the energy-releasing process by which large molecules are broken down into smaller ones, and anabolism (a-nabo-lizm), the energy-requiring process by which small molecules are joined to form larger ones. Catabolism begins during the process of digestion and is concluded within individual cells. Anabolism occurs in all cells of the body as they divide to form new cells, maintain their own intracellular structure, and produce molecules such as hormones, neurotransmitters, or extracellular matrix molecules for export. Metabolism can be divided into the chemical reactions that occur during digestion and the chemical reactions that occur after the products of digestion are taken up by cells. The chemical reactions that occur within cells are often referred to as cellular metabolism. The digestive products of carbohydrates, proteins, and lipids can be further broken down inside cells. Which pathways function and how much each pathway is used is determined by enzymes because each step in the pathway requires a specific enzyme (see chapter 2). Thus, the types and amounts of enzymes present in cells are under genetic control. The combination of a chemical signal, such as a neurotransmitter or hormone, with a membrane-bound or intracellular receptor can activate or inhibit enzyme activity (see chapter 10). The end product of a biochemical pathway can inhibit the enzyme responsible for the first reaction in the pathway. This negative-feedback regulation prevents accumulation of the intermediate products and the end product of the pathway (figure 17. Carbohydrate Metabolism Monosaccharides are the breakdown products of carbohydrate digestion. Glucose is transported in the circulation to all tissues of the body, where it is used as a source of energy. Any excess glucose in the blood following a meal can be used to form Regulation of Metabolism the products of digestion, such as glucose, fatty acids, and amino acids, are molecules containing energy within their chemical bonds. For example, in Tay-Sachs disease, the breakdown of lipids within lysosomes is impaired. Glycogen is a short-term energy-storage molecule that the body can store only in limited amounts, whereas lipids are long-term energy-storage molecules that the body can store in large amounts. Glycolysis Glycolysis (gli-kol i-sis) is a series of chemical reactions that occurs in the fluid part of cytoplasm surrounding the organelles. It results in the breakdown of glucose to two pyruvic (pi-roo vik) acid molecules (figure 17. Glucose consists of 6 carbon atoms, 12 hydrogen atoms, and 6 oxygen atoms covalently bonded together. During the breakdown of glucose, a hydrogen ion (H+) and two electrons (e-) are released and can attach to a carrier molecule, which moves the H+ and electrons to other parts of the cell. Lactic acid is released from the cells that produce it, and blood transports it to the liver. When O2 becomes available, the lactic acid in the liver can be converted through a series of chemical reactions into glucose. Glucose 2 Anaerobic respiration, which does not require O2, includes glycolysis and converts the two pyruvic acid molecules produced by glycolysis to two lactic acid molecules. The six-carbon glucose molecule is broken down to form two molecules of pyruvic acid, each consisting of three carbon atoms. Each acetyl group combines with coenzyme A (CoA), derived from vitamin B2, to form acetyl-CoA. Each acetyl-CoA combines with a fourcarbon molecule to form a six-carbon citric acid molecule, which enters the citric acid cycle. The citric acid cycle is a series of reactions wherein the six-carbon citric acid molecule is converted, in a number of steps, into a four-carbon molecule (figure 17. The four-carbon molecule can then combine with another acetyl-CoA molecule to form another citric acid molecule and reinitiate the cycle. The electron-transport chain is a series of electron-transport molecules attached to the inner mitochondrial membrane (figure 17. As glucose is broken down, the carbon atoms from glucose are incorporated into carbon dioxide. Some of the electron-transport carriers are also H+ pumps, which use some of the energy from the transported electrons to pump H+ from the inner to the outer mitochondrial compartment. Because of an increased H+ concentration in the outer compartment, the H+ passes by diffusion back into the inner compartment. In the last step of the electron-transport chain, two H+ and two electrons combine with an O2 atom to form H2O: 2 H+ + 2 e- + 1 O2 2 H 2O Without O2 to accept the H+ and electrons, the citric acid cycle and the electron-transport chain cannot function. Note that the O2 we breathe in is eventually bound to two hydrogen atoms to become water, which has many uses in the body (see chapter 2). Predict 5 Many poisons function by blocking certain steps in the metabolic pathways. In addition, many of the chemical reactions of aerobic respiration can be used to produce energy from other food molecules, such as lipids and proteins (see "Lipid Metabolism" and "Protein Metabolism" next). Between meals, triglycerides in adipose tissue are broken down into fatty acids and glycerol. Other tissues, especially skeletal muscle and the liver, use the fatty acids as a source of energy. It occurs by a series of reactions wherein two carbon atoms are removed from the end of a fatty acid chain to form acetyl-CoA (figure 17. As the process continues, carbon atoms are removed two at a time until the entire fatty acid chain is converted into acetyl-CoA. In the liver, two acetyl-CoA molecules can also combine to form ketones (ke tonz). The ketones are released into the blood and travel to other tissues, especially skeletal muscle. The presence of small amounts of ketones in the blood is normal and beneficial, but excessive production of ketones is called ketosis (ke-to sis). Conditions that increase lipid metabolism can increase the rate of ketone formation. Examples are starvation (see the Clinical Impact "Starvation and Obesity" later in this chapter), diets consisting of proteins and fats with few carbohydrates, and untreated diabetes mellitus (see chapter 10). Because ketones are excreted by the kidneys and lungs, characteristics of untreated diabetes mellitus include ketones in the urine and "acetone breath. Once amino acids are absorbed into the body, they are quickly taken up by cells, especially in the liver. Amino acids are used primarily to synthesize needed proteins and only secondarily as a source of energy. Ammonia is toxic to cells, so the liver converts it to urea, which the blood carries to the kidneys, where it is eliminated. The -keto acid can enter the citric acid cycle or can be converted into pyruvic acid, acetyl-CoA, or glucose. Although proteins can serve as an energy source, they are not considered major storage molecules. Nutrition, Metabolism, and Body Temperature Regulation 491 Metabolic States the body experiences two major metabolic states. The first is the absorptive state, the period immediately after a meal, when nutrients are being absorbed through the intestinal wall into the circulatory and lymphatic systems (figure 17. The absorptive state usually lasts about 4 hours after each meal, and most of the glucose that enters the circulation is used by cells for the energy they require. Many of the absorbed amino acids are used by cells in gene expression, and some are used for energy; still others enter the liver and are converted to lipids or carbohydrates. The second state, the postabsorptive state, occurs late in the morning, late in the afternoon, or during the night after each absorptive state is concluded (figure 17. During the postabsorptive state, blood glucose levels are maintained by the conversion of other molecules to glucose. The first source of blood glucose during the postabsorptive state is the glycogen stored in the liver. The glycogen stored in skeletal muscles can also be used during vigorous exercise. In the liver, acetyl-CoA can be used to produce ketone bodies that other tissues can use for energy. The use of fatty acids as an energy source can partly eliminate the need to use glucose for energy, so that less glucose is removed from the blood and homeostasis is maintained. The amino acids of proteins can be converted to glucose or can be used to produce energy, again sparing blood glucose. Metabolic Rate Metabolic rate is the total amount of energy produced and used by the body per unit of time. Metabolic rate is usually estimated by measuring the amount of oxygen used per minute. Metabolic energy can be used in three ways: for basal metabolism, for muscle contraction, and for the assimilation of food, which involves processes such as the production of digestive enzymes and the active transport of digested molecules. It is the metabolic rate calculated in expended kilocalories per square meter of body surface area per hour. Nutrients Absorbed Nutrients are absorbed from the digestive tract and carried by the blood to the liver. Nutrients Processed the liver converts nutrients into energy-storage molecules, such as glycogen, fatty acids, and triglycerides. Amino acids Triglycerides Glucose Proteins Nonessential amino acids Glycogen Glycerol -keto acids Ammonia Energy Acetyl-CoA Urea Fatty acids Nutrients Stored and Used Nutrients are stored in adipose tissue as triglycerides and in muscle as glycogen. Molecules not immediately needed for energy are stored: Glucose is converted to glycogen or triglycerides, triglycerides are deposited in adipose tissue, and amino acids are converted to triglycerides or carbohydrates. Muscle Proteins Glycogen Adipose tissue Triglycerides Most tissues (including muscle) Energy Nervous tissue Energy Amino acids Glucose Glycerol Fatty acids Fatty acids Ketone bodies Glucose Energy Nutrients Processed the liver processes molecules to produce additional energy sources: Glycogen and amino acids are converted to glucose and fatty acids to ketones. Basal metabolism supports active transport mechanisms, muscle tone, maintenance of body temperature, beating of the heart, and other activities. The daily input of energy should equal the energy demands of metabolism; otherwise, a person will gain or lose weight. For a 23-year-old, 70-kg (154-lb) male to maintain his weight, the input should be 2700 kcal/day; for a 58-kg (128-lb) female of the same age, 2000 kcal/day are necessary. Reducing kilocaloric intake by 500 kcal/day can result in the loss of 1 lb of fat per week. Physical activity through skeletal muscle movement (exercise) greatly increases the metabolic rate. In the average person, basal metabolism accounts for about 60% of energy expenditure, muscular activity 30%, and assimilation of food about 10%. Of these amounts, energy loss through muscular activity is the only component that a person can reasonably control. Comparing the number of kilocalories gained from food and the number of kilocalories burned during exercise reveals why losing weight is difficult. For example, if brisk walking uses 225 kcal/h, it takes 20 minutes of brisk walking to burn off the 75 kcal in one slice of bread (75/225 = 0. Research suggests that a combination of appropriate physical activity and appropriate kilocaloric intake is the best approach to maintaining a healthy body composition and weight. Although at one time he weighed less as a result of dieting, he has not only regained the lost weight but also gained additional weight. Because of his extreme obesity and related health problems, Les elects to have a Roux-en-Y gastric bypass. In this procedure, the digestive tract is surgically rearranged to form a Y-shaped structure. One arm of the Y is formed by separating the superior part of the stomach to form a small pouch that is connected to the jejunum. The small size of the stomach pouch dramatically reduces the amount of food a person can eat. The other arm of the Y consists of the remainder of the stomach, the duodenum, and part of the jejunum. Food from the esophagus enters the small stomach pouch and bypasses the rest of the stomach and the duodenum by entering the jejunum. Roux-en-Y is the most commonly performed gastric bypass surgery in the United States.

It is important to note that in Croatia antibiotics high blood pressure order cephalexin 500 mg fast delivery, endovascular treatment of vascular injury is very rarely indicated or performed suggested antibiotics for sinus infection order cephalexin on line amex. Although a radiologist is on-call in the hospital 24 hours a day virus 88 order cephalexin 500mg with mastercard, this may not be an interventional radiologist infection 3 months after wisdom teeth removal best buy for cephalexin. This study allows the trauma and vascular surgeons to examine the findings and to consult interventional radiology for further imaging as necessary antibiotic xanax order cephalexin 250 mg visa. If this is not possible because the injury is more extensive bacterial zoonoses buy 250 mg cephalexin overnight delivery, an end-to-end anastomosis may be considered. The difference between high-energy, wartime injuries and low-energy civilian wounds should also to be considered when selecting the type of vascular repair and the type of conduit. The contaminated nature of penetrating wartime injuries makes the use of saphenous vein grafts especially appealing because they are felt to be better incorporated and more resistant to infection than synthetic grafts. It is important to remember that, in some cases, ligation of the vessel or even primary amputation is indicated as a quick damage control maneuver. In Croatia the challenge of how best to improve the skills of trainees in trauma surgery is also complicated by the declining number of open vascular reconstructions. Although endovascular procedures are rare in vascular trauma, they are more common in the treatment of age-related disease, which detracts from the open vascular experience of trainees. Lackovic Z, Markeljevic J, Marusic M: Croatian medicine in 1991 war against Croatia: a preliminary report. Lovric Z, Wertheimer B, Candrlic K, et al: War injuries of major extremity vessels. Lovric Z, Wertheimer B, Candrlic K, et al: Reconstruction of the popliteal artery after war injury. Lovric Z, Lehner V, Wertheimer B, et al: Tourniquet occlusion technique for lower extremity artery reconstruction in war wound. Radoni V, Bari D, Petricevi A, et al: Military injuries to the popliteal vessels in Croatia. Strategies to Sustain and Train the Next Generation of Trauma Surgeons the training of surgeons in Croatia is currently being reformed. During the training, 2 years are spent in a "common trunk" of general surgery followed by 3 years of training in one of several subspecialties, such as trauma or orthopedic, abdominal, vascular, or cardiac. The common trunk training does involve 3 months of vascular surgery education and thus potentiates the trauma surgeon, as well as other surgical subspecialists, to be capable of diagnosing and managing vascular trauma. In addition, the laws in Croatia support the trauma surgeon in performing an urgent vascular reconstruction. The only limitations for these individuals in managing the spectrum of vascular trauma may be those related to lack of current experience with this complex injury pattern. The first suture of an injured brachial artery was performed by Halliwell as reported by Richard Lambert in a letter to William Hunter in 1759. The European Union has 28 member countries and has been a significant organ for peace during the decades it has existed, but the history of Europe is that of strife, conflict, and war. Cultural, religious, ethnic, political, and other differences have prevented any uniform tradition of medicine from being accepted on the continent. Despite a history of war, most of Europe has enjoyed a high standard of living for decades, even centuries, and an element of legal protection of the work force for more than a century. That has meant regulation of traffic, construction, industries, and many other areas of life-meaning that the way of living and the work environment-produces few injuries. An example from a study by Magee et al from Oxford University is telling: 47 vascular injuries requiring operation in 10 years, 11 of them for penetrating injuries, all as a result of stabbing. The former northern colonial superpower, the Netherlands, has enjoyed an immensely high standard of living for 5 centuries. The border between Finland and Russia is one with extremes in economic and health-care terms. Russia is very large as a country (300 million inhabitants), but its economy is still only slightly larger than that of Spain with 46 million inhabitants and onetenth that of the European Union. The overall favorable financial development in Northern Europe has meant easier and more-common adoption of technology in the management of vascular disorders. As a specialty, vascular surgery has gone through a revolution during the past decade and has become very technology driven. The development has been so rapid that endovascular options in trauma management did not really even exist according to a European review of vascular injuries published in 2002. This change is also reflecting itself in the treatment of vascular injuries, bringing along additional challenges in organizing the care of these patients. Region-Specific Epidemiology In contrast to the United States and some other countries with high incidence of penetrating trauma, a significant proportion of vascular injuries in Northern Europe are caused by blunt trauma and, increasingly, by iatrogenic injuries. Vascular surgery is an independent specialty or a subspecialty of general surgery; and the vascular surgeon is the one who is mainly responsible for the treatment of vascular injuries, except for Germany and the Netherlands where trauma surgeons perform the first-line surgery. Endovascular treatment options are available in most countries, but mainly in large academic centers. With increasing fragmentation of surgical training and with the growing potential of endovascular treatment options, major challenges remain in both the organization of emergency surgery care and the training of a new generation of surgeons who are capable of working in this new environment. In countries within the Austro-German surgical tradition, orthopedic-oriented trauma surgeons were trained to manage injuries in almost all body sites, including visceral and vascular injuries. In contrast, in the Mediterranean countries, Baltic States, and most of Western Europe, general and visceral surgeons increasingly took over the management of nonskeletal injuries. According to a trauma audit of Finnish hospitals, the annual incidence of severe trauma in 2004 was 19 to 25 per 100,000 inhabitants. In countries with large land areas and small populations, regionalization of all emergency surgery services (combining trauma and nontrauma surgical emergency care) seems to be the best option. To successfully combine the requirements of producing high-level and affordable elective and emergency surgical services remains one of the most difficult surgical training challenges for the near future. Larger units can afford to have more expensive and yet cost-effective infrastructure. In the case of trauma surgery, it is vascular problems that may call for very urgent management and expertise. In those situations, there may not be time to send a patient to a tertiary hospital, because a life or a limb may be lost in the process. According to an informal survey performed by the authors with colleagues from Northern Europe, vascular surgery is an independent surgical specialty in most countries with the exception of some Scandinavian countries and Poland. The majority of vascular injuries are managed by vascular surgeons, except in Germany and the Netherlands where trauma surgeons are responsible for the first-line treatment (Table 28-1). However, all Scandinavian countries (except for Denmark) have small populations in a geographically large country. Despite helicopter services, time can become a factor, especially in the autumn or winter when helicopter transportation of patients can be problematic. Duplex ultrasonography is not taught to all resident surgeons, although the devices would be readily available. Vascular surgery residents are expected to learn the basics of duplex scanning, although it is not mandatory. Region-Specific Treatment Strategies the two essential components in managing major vascular injuries are the control of bleeding (an endovascular approach is often possible) and reconstruction of vessels (arteries and veins). Transportation of patients to major centers is preferred; but, in regions such as Lapland in northern Scandinavia, it can mean a distance of several hundred kilometers in difficult weather conditions. Fixedwing aircraft is not used, although their use has been discussed with the air force in many countries. Combining military pilot training and patient transportation may be a possibility in remote areas in the future, although financial constraints due to recession are felt everywhere in the western world at the moment. Endovascular surgery has very strong proponents in the Northern European surgical community, and it has been included in the training of vascular surgeons early on. Trauma work takes a lot of imagination and creative thinking; but it also requires a large stock of expendables. Region-Specific Considerations for Diagnosis In many centers throughout the world, radiologists protect their interests jealously and have at times initially even refused to train surgeons in their units. In Central Europe a specialty called "angiology" exists, combining internal medicine and radiology. These turf wars have been seen everywhere, but they are detrimental to patients, especially those suffering from vascular trauma. These technological trends also show themselves in the annual health expenditure; the United States spends a third more per capita than Scandinavian countries (U. The worrisome fragmentation in medical care is seen in the management of vascular injuries as well. Carrel A: La technique operatoire des anastomoses vasculaires et de la transplantation des visceres. Katzen B, Chang J: Percutaneous transluminal angioplasty with the Gruentzig balloon catheter. Katsanos K, Sabharwal T, Carrel T, et al: Peripheral endografts for the treatment of traumatic arterial injuries. Schanzer A, Steppacher R, Eslami M, et al: Vascular surgery training trends from 2001-2007: a substantial increase in total procedure volume is driven by escalating endovascular procedure volume and stable open procedure volume. Harmonization of various curricula would be useful, but the conditions are quite different in European countries, even within the European Union. Fragmentation of the knowledge and skills of surgeons is a problem all over the western world. Even varicose veins tend to be managed by vascular specialists and interventional radiologists-or even dermatologists-but rarely by general surgeons, because there is a growing demand for more-focused surgery where the surgeon performs a duplex scan on the patient prior to surgery. The emergence of endovascular techniques has made it possible to treat up to 70% of abdominal aortic aneurysms using intravascular stent prostheses. Training paradigms will have to change to reflect the needs for changes in the delivery system of surgical emergency care. After that, trainee surgeons concentrate on their own field of specialized (elective) surgery. That creates the problem of how to provide those services in a smaller (nonuniversity) hospital setting where many types of emergency procedures are rare. On the other hand, similar services are needed for problems related to chronic limb ischemia. A study in the United States showed that the volume of open vascular operations performed by trainees had not decreased during the last decade. In fact, there had been an increase driven by escalating endovascular procedure volume. The thesis of Nikolai Pirogov, one of the founders of military surgery, investigated the consequences of experimental ligation of the abdominal aorta (1832); and he provided detailed information concerning the diagnosis and surgical care of major vascular injuries in his textbook "The Principles of War Surgery" (1864). During the Russo-Japanese War, while studying the possibility of ligating arteries in cases of aneurysm, Nikolai Korotkov invented a method of measuring blood pressure by identifying "Korotkov sounds" (1905). In 1945, Vasily Gudov and coauthors developed the vascular circularsuturing device. Institutes of cardiovascular surgery and cardiovascular units of hospitals dedicated to caring for elective and emergency vascular pathology. In 1987, professor Nikolai Volodos in Kharkov, Soviet Union (now in Ukraine) first in the world performed an endovascular repair for a post-traumatic pseudoaneurysm in descending aorta. Important contributions to the treatment of casualties were made by the personnel of Kirov Military Medical Academy in Saint-Petersburg, especially by those of the War Surgery Department, as well as by the staff of central hospitals in Moscow, such as N. Equally important were the efforts of surgeons at district military hospitals and garrison hospitals in frontier zones, as well as those in forward medical units, such as medical companies, separate medical battalions (similar to U. The most significant progress in providing care to patients with major vascular injuries occurred during the war in Afghanistan and the armed conflicts in the North Caucasus. The epidemiology of vascular injuries, the organizational aspects of providing care, and the military trauma system all differed significantly between the conflicts in Afghanistan and the North Caucasus. Afghanistan Region-SpecificEpidemiology the rate of major vascular injuries occurring during the Afghanistan war ranged from 2% to 8% of all injured combatants (mean: 4. Arterial injuries were sometimes associated with gunshot-induced bone fractures (42. Patients with major vascular injuries belonged to a group of severely injured patients. The majority of these who were transported to the medical facilities were either in stable condition (24. Massive blood loss and severe associated injuries, specifically blast injuries, were commonly accompanied by impaired consciousness. The rate of vascular injuries among all injured combatants in Afghanistan amounted to 4. Surgical approaches to injured arteries of the extremities were based on the type of acute ischemia. In the setting of compensated ischemia, there are no indications for urgent vascular reconstruction, as safe ligation of the artery is possible. In irreversible ischemia, amputation is justified; because arterial reconstruction under field conditions after this length of time without perfusion may lead to the death from endotoxemia. In both conflicts, military surgeons in medical units near the point of injury carried out damage control surgical tactics, such as temporary shunting of the injured arteries. Next, patients were evacuated and underwent definitive vascular reconstruction by vascular surgeons at larger frontline military hospitals.

When an operation for another injury is indicated in a patient with blunt cardiac injury virus - f buy cephalexin with visa, not including cardiac rupture virus with headache cheap cephalexin 250mg on line, the prognosis is generally excellent antibiotic generations cheap cephalexin 250mg without a prescription. In the report by Flancbaum et al antibiotics for uti to buy purchase cephalexin visa, 19 patients with blunt cardiac injury had an emergency operation antibiotic resistance peer reviewed journal generic 500 mg cephalexin fast delivery, including 15 on the day of admission antibiotics gut flora cheap cephalexin 500 mg line. The duration of anesthesia was 6 hours, and there were no cardiac-related complications or deaths. The same incision(s) would be used in the operating room for agonal patients or for those having gone into cardiac arrest particularly following transmediastinal gunshot wounds. These incisions allow for expedited control of hemorrhage from cardiac perforation(s) and for cross-clamping of the descending thoracic aorta. The anterolateral thoracotomy approach may also be kept separate from any abdominal midline incision needed to address intraabdominal injury. The median sternotomy is performed in the operating room in patients who are more hemodynamically stable and who have solitary anterior stab wounds. In such patients, multiple cardiac perforations are unlikely and cross-clamping of the descending thoracic aorta is usually not needed. Pericardiotomy Opening of the left chest via an anterolateral thoracotomy requires a Finochietto retractor after which a longitudinal left lateral pericardiotomy can be performed anterior to the left phrenic nerve. In obese patients where fat obscures the phrenic nerve, the accompanying pericardial-phrenic vessels mark the location. Even if the pericardium is difficult to grab with a forceps secondary to distention of the sac with blood, the surgeon should resist performing a pericardiotomy with a scalpel. This is a particularly dangerous as right-sided tamponade from a wound to the atrium or ventricle may push the heart to the left so that it lies immediately underneath or abuts the left pericardial sac. In this position, the left anterior descending coronary artery is at risk of injury if a scalpel is passed too deep while opening the pericardium. A better technique is to lift the pericardium with a toothed forceps and to open the sac with the tip of a straight Mayo scissors. Once it has been opened, the pericardium generally lifts away from the surface of the heart allowing the incision to be extended in a superior direction until the pericardial fold on the great vessels is reached. The longitudinal left pericardiotomy is completed in an inferior direction until the left hemidiaphragm is reached. This pericardial incision is made at a right angle to the left lateral pericardiotomy and extends to 1 cm anterior to the right phrenic nerve. In patients undergoing a bilateral anterolateral thoracotomy, either the pericardiotomy described above or the midline pericardiotomy described below can be used. After a median sternotomy and insertion of a Finochietto retractor, the epicardial fat and the anterior extensions of the parietal pleura are swept laterally with the fingers over laparotomy pads. This maneuver exposes the anterior surface of the pericardial sac which is grasped with toothed forceps and opened in a midline longitudinal direction from the great vessels to the diaphragm. Control of Hemorrhage from the Heart (Table 9-2) After the pericardiotomy is performed, blood and thrombus are removed from the pericardial sac manually and with irrigation and suction. A rapid inspection of the anterior surface of the heart and great vessels is performed. A profoundly hypotensive patient may not tolerate inspection of the posterior aspect of the heart, which requires elevation of the apex. Lifting the heart to inspect the underside compresses or kinks the vena cava, restricting right-sided filling. This maneuver also carries with it a risk of sucking air into an open Table 9-2 Techniques for the General Surgeon to Control Hemorrhage from a Cardiac Perforation or Rupture Atrium/ventricle Atrium/ventricle Atrium Lateral atrium adjacent to pericardium or atrium adjacent to ventricle Atrium/ventricle Ventricle Large ventricular hole or multiple chamber wounds Finger Stapler Satinsky vascular clamp row of Allis clamps Foley balloon catheter Crossed mattress sutures Inflow (superior vena cava/ inferior vena cava) occlusion 3-mg intravenous adenosine to induce 10 to 20 seconds asystole. With left ventricular perforation, air has the potential to rapidly move into the coronary arteries causing an air embolism and cardiac arrest. As such, manual palpation of the posterior surface of the heart without elevation of the apex is all that is advised until the patient is resuscitated with a relatively normal blood pressure. Palpation of a posterior defect or jet of blood as a ventricle contracts mandates leaving the finger in place for control of hemorrhage until the aforementioned status can be reached. Once the patient has been stabilized and the surgeon is ready to lift the apex of the heart to inspect the posterior aspect, he or she should notify the anesthesia team so that they are aware and can assist in managing any associated hypotension. If there is bleeding from this posterior aspect of the heart that will require prolonged elevation and/or suturing, the surgeon should consider placing a cross-clamp on the descending thoracic aorta to preserve central pressure and cerebral circulation. A finger or compression with fingers will control hemorrhage from cardiac perforation or cardiac rupture in 95% to 96% of patients. This is because patients with larger defects die at the scene or in transit and are generally not alive to undergo operation. When a finger is not successful in controlling bleeding or when more definitive control is needed, the techniques in Table 9-2 may be applied. Disposable skin staplers with long rotating heads have been used to quickly close atrial or ventricular defects for over 2 decades. The safest policy is to buttress any ventricular repair with Teflon pledgets in the operating room in patients who stabilize after the initial hemorrhage control and resuscitation maneuvers. Elevation of an atrial wound with the fingers, forceps, or Allis clamps will frequently allow placement of a Satinsky vascular clamp under the perforation. Atrial wounds or ruptures in the lateral aspect adjacent to the pericardium or anteriorly or posteriorly adjacent to the ventricle cannot be controlled with a Satinsky. With these injuries, Allis clamps grabbing both sides of the defect are placed in a row similar to the method described for wounds to the vena cava for the past 100 years. Use of a Foley balloon catheter to control hemorrhage from a difficult cardiac location after a penetrating wound was first described in 1966. On rare occasions, the length of a ventricular laceration will lead to exsanguinating hemorrhage that will preclude the use of the stapler or the balloon catheter. With manual compression of the defect, a horizontal mattress suture is rapidly placed on either side of the defect, the two ends on each side are placed in the hands, and the hands holding the suture ends are crossed. This should prevent exsanguination as a continuous over-and-over suture row or a row of staples is placed. A temporary closure as described would then be buttressed with Teflon pledgets in the operating room. Because few trauma surgeons are familiar with the bimanual technique for control of hemorrhage from the heart described over a century ago by Ernst Ferdinand Sauerbruch (1875-1951), the related technique of inflow occlusion is used occasionally to control major hemorrhage from the heart. Harken (1910-1983) as a technique to slow the heart and to allow for removal of intracardiac foreign bodies. This maneuver decreases hemorrhage from the injured heart and rapidly causes a profound bradycardia. The decreased blood in the operative field and a low heart rate will allow for clamp or suture control of hemorrhage from complex cardiac wounds. Prior to tying down the last suture of a ventricular repair, the clamps on the cavae are removed to allow for refilling of the ventricle. Evacuation of ventricular air is accomplished by elevation of the apex of the heart as refilling occurs and before the final suture of the repair is tied down. The exact time limit on inflow occlusion is unknown, but 1 to 2 minutes will usually allow for a restoration of a cardiac rhythm after the repair has been completed. There have been several reports about the administration of 3 mg of adenosine intravenously to aid in the repair of cardiac injuries. The annoying side effects associated with adenosine use, including facial flushing, thoracic discomfort, dyspnea, and headache, are not noticeable under general anesthesia. If the heart feels empty, the descending thoracic aorta should be cross-clamped if this has not been performed previously. If a median sternotomy was the original approach, a left anterolateral thoracotomy will have to be performed to complete this maneuver. It is critical not to lift the apex of the heart because this may cause impingement of the vena cavae or the previously described air embolism from the partially empty cardiac chamber with perforation. When the heart does not respond to the infusion of volume and internal cardiac massage, cardioactive medications should be administered. These include 1 mg intravenous atropine for bradycardia, 1 mg to 3 mg intravenous epinephrine for bradycardia and hypotension, or 1 mg to 3 mg of intracardiac (into left ventricle) epinephrine for profound bradycardia or asystole. The onset of ventricular fibrillation is treated with internal electrical defibrillation using two paddles in contact with the heart anteriorly and posteriorly and 20 Ws as the initial electrical charge. After restoration of a satisfactory cardiac rhythm and blood pressure, suture repair of the cardiac perforation may be performed. A most helpful maneuver to stabilize the beating heart as repair is being performed is "clamp control of the right ventricular angle" as described at Temple University. Repair of an atrial perforation or rupture above a Satinsky is performed with a pursestring or continuous 4-0 or 5-0 polypropylene suture. An alternate approach to a hole in the atrial appendage is to place a 2-0 silk tie under the Satinsky clamp much like in performing a decannulation maneuver following cardiopulmonary bypass. As noted, Allis clamps are used to control hemorrhage from atrial wounds in the lateral aspect adjacent to the pericardium or in those adjacent to the ventricle. Repair is accomplished with a continuous or interrupted mattress technique using 4-0 polypropylene suture passed under the row of Allis clamps. Therefore, as the continuous 3-0 or 4-0 polypropylene sutures are placed around the controlled defect, the balloon must be temporarily pushed down into the ventricle with each passage of the needle. Hemorrhage will occur with this maneuver, but rupture of the balloon is prevented. Teflon pledgets are used to buttress ventricular repairs performed with sutures alone in the emergency department and any repairs performed in the operating room. The technique is to first pass the two needles of a 4-0 polypropylene suture through a pledget 6 mm to 10 mm long and 3 mm to 5 mm wide. The two needles are then passed through another Teflon pledget of similar size and then cut off. As the two ends are pulled up tight, the second pledget is moved down to its side of the ventricular wound aided by ample irrigation on the monofilament sutures. Tying the polypropylene suture with appropriate tension will bring the Teflon pledgets in apposition, will seal the cardiac perforation, and will prevent the sutures from tearing through edematous myocardium. One technique for a cardiac surgeon to repair a wound is the use of a sutureless patch and bioglue. This technique appears to be most useful for small wounds in difficult-torepair areas of the heart, such as the coronary sinus. Even with this modified technique, tying the pledgets together to once again control hemorrhage may cause compression of the coronary artery and ischemia of the distal myocardium. A direct, but limited, laceration of a proximal coronary artery may be repaired with interrupted single 6-0 or 7-0 polypropylene sutures on rare occasions. In contrast, a laceration of a distal coronary artery near the apex of the heart is treated with ligation and a 15-minute period of observation to assess myocardial ischemia. Acute Need for Cardiopulmonary Bypass the majority of patients who reach the hospital with signs of life despite a cardiac perforation or rupture have a limited injury that can be repaired by a general surgeon or by a senior surgical resident. Approximately 3% to 4% of such patients have a more complex injury that can only be repaired by a cardiac surgeon using cardiopulmonary bypass (Table 9-3). Treatment in the Operating room After Cardiorrhaphy If a left anterolateral or bilateral anterolateral thoracotomy has been performed, the superior and inferior transected ends of the internal mammary arteries should be clamped and ligated with 3-0 silk ties. As the heart is usually edematous after a repair, the pericardial sac is not closed if a median sternotomy and midline pericardiotomy have been used for exposure. Closure of this lateral defect with interrupted 2-0 silk sutures would then be appropriate. The pericardial sac is drained with a rightangle 36 Fr thoracostomy tube inserted through the epigastric area of the abdominal wall. If either pleural cavity has been opened, one or two 36 Fr thoracostomy tubes are placed through the 5th intercostal space between the ipsilateral anterior and middle axillary lines. On occasion, epicardial pacing wires may have to be sewn to the heart when arrhythmias continue despite cardiac repair and resuscitation. An unstable patient who is not fully responsive to continuing resuscitation and inotropes may benefit from the transfemoral insertion of an intraaortic balloon pump before transfer to the intensive care unit. Certain patients will not tolerate wire closure of the sternum after a cardiac repair, presumably due to compression of the edematous heart. A plastic silo (a genitourinary irrigation bag opened on three seams) should be sewn to the skin edges of the median sternotomy with continuous sutures of 2-0 nylon as a temporary closure maneuver. As the patient enters the diuretic phase of recovery in the subsequent 48 to 72 hours, the silo is removed; and the sternum is closed at a reoperation. MajorComplications Cardiac Failure Cardiac failure after repair of a traumatic injury may require the use of inotropic medications and/or an intraaortic balloon pump. Possible causes of cardiac failure in these cases are as follows: (1) tamponade from a coagulopathy, hemorrhage from the repair, or hemorrhage from missed injury; (2) cardiac compression from closure of the sternum; (3) posttraumatic acute myocardial infarction without injury to a coronary artery42; (4) posttraumatic acute myocardial infarction with injury to a coronary artery; and (5) undiagnosed injury to a cardiac valve, a papillary muscle, the chordae tendinae, or the atrial or ventricular septum. Cardiac compression from closure of the sternum is unusual and remains the diagnosis of exclusion. Delayed Diagnosis of Intracardiac Lesions For more than 55 years, it has been recognized that patients who survive acute repair of a wound or rupture of the atrium or ventricle may also have an internal cardiac injury. Patients with hemodynamically significant injuries, particularly those to a valve, a papillary muscle, the chordae tendinae, or the septum should have delayed repair on cardiopulmonary bypass40,44,46 (Table 9-3). When considering all patients who require cardiopulmonary bypass for repair of cardiac trauma those requiring its use in the delayed setting account for 85% to 90% of cases. Survival Survival after penetrating cardiac trauma depends on the mechanism of injury (stab versus gunshot), the number of signs of life on admission (cardiovascular and respiratory components of trauma score), the location of the thoracotomy (emergency department versus operating room), the cardiac rhythm at time of the pericardiotomy (rhythm versus asystole), the number of chambers injured, and the associated injuries. Injuries to the Great Vessels Definition/Classification the great vessels in the chest and thoracic outlet are variously defined, but most consider this category to include the large vessels originating from the aortic arch and those in what is traditionally considered zone I of the neck. In this context, the terminology may also include the ascending, transverse, and proximal descending aorta as well as the innominate (brachicephalic), common carotid and the subclavian arteries. Because of their sizes and proximal locations, the innominate and central jugular veins may also be included as great vessels of the chest. Table 9-6 provides the American Association for the Surgery of Trauma Thoracic Vascular Organ Injury Scale for vascular trauma in this region.

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While graft infection in the immediate postoperative period and in the short term are not highly reported rotating antibiotics for acne buy generic cephalexin 250mg line, ominous signs include fever bacteria in urine culture buy cheap cephalexin 500 mg on line, leukocytosis antibiotics for sinus infection online order cephalexin with paypal, and continued bleeding antibiotics green poop purchase cephalexin in united states online. For later manifestation of venous injury bacteria are examples of buy cephalexin online from canada, imaging modalities are the keys to discovery antibiotics for acne make me feel sick 500mg cephalexin overnight delivery. However, if the peroneal was the sole remaining artery, revascularization of the anterior or posterior tibial artery is necessary for limb salvage. In blunt trauma, there is a high incidence of limb loss that increases when there is ischemia on presentation. As such, the authors generally perform prophylactic fourcompartment fasciotomy of the leg utilizing a two-incision approach for those at risk for compartment syndrome: namely, those patients with prolonged ischemia (>4 hours) before revascularization and severe infrageniculate leg injury. The authors also have a low threshold to perform leg fasciotomy in patients who have had ligation of a large extremity venous injury, those who have had hemorrhagic shock requiring significant resuscitation, and those with combined arterial and venous injuries. A longitudinal skin incision lateral to the tibia is used to visualize the anterior and lateral compartments. Care must be taken to avoid the superficial peroneal nerve and the saphenous vein. Also, when decompressing the anterior and lateral compartments, the intermuscular septum should be identified to ensure that both compartments have indeed been opened and that one is not misguided by the appearance of the similar muscle groups. Conclusion Extremity vascular trauma is common in both the civilian and the military settings. Recent experience in the wars in Afghanistan and Iraq has confirmed the imperative of initial hemorrhage control including the use of tourniquets and direct or manual pressure with or without hemostatic agents if possible. Once hemorrhage control has been achieved, management options include (1) continued tourniquet application or ligation of the vascular injury, (2) restoration of perfusion (arterial and/or venous) with a temporary vascular shunt, and (3) vascular reconstruction either initially or following use of a vascular shunt. The choice of management depends on the anatomic location of the extremity vascular injury; whether it is arterial, venous, or both; the extent of the mangled extremity; and the physiologic status of the patient. While simple vascular reconstruction may be possible for uncomplicated, isolated vascular injuries cared for by experienced surgeons, more complex injury patterns occurring in the setting of the mangled extremity benefit greatly from damage control adjuncts and from a multidisciplinary approach. Kurtoglu M, Yanar H, Taviloglu K, et al: Serious lower extremity venous injury management with ligation: prospective overview of 63 patients. Kuralay E, Demirkilic U, Ozal E, et al: A quantitative approach to lower extremity vein repair. Lynch K, Johansen K: Can Doppler pressure measurement replace "exclusion" arteriography in the diagnosis of occult extremity arterial trauma A comprehensive overview of the prehospital care of the trauma patient has been provided for both the civilian6 and military7 settings. This chapter will focus more directly on two aspects of prehospital care-stopping the bleeding that results from vascular trauma and preventing and treating hemorrhagic shock. It focuses intensely on minimizing blood loss in injured warriors, and it has rapidly gained traction as an effective means of reducing combat death. Every effort is also made to ensure that limbs are saved whenever possible and that other avoidable adverse outcomes from the trauma are minimized. It is useful to think of hemorrhage in the prehospital setting as being one of the following two types: compressible (either extremity hemorrhage or external hemorrhage not suitable for a tourniquet) or noncompressible (internal). The extremities are the most commonly injured anatomic region in the combat wounded, representing over 50% of all anatomic combat wounds. Tourniquets are used aggressively on the battlefield to control extremity hemorrhage; hemostatic dressings, such as Combat Gauze, are used for compressible hemorrhage that occurs in anatomic locations not amenable to tourniquet use; new interventions for junctional hemorrhage control are being introduced; and tranexamic acid, an antifibrinolytic agent, is now being used to help improve survival in casualties with noncompressible hemorrhage. There is also an increased focus on the prevention and management of trauma-associated coagulopathy, on hypothermia prevention, and on the use of hypotensive resuscitation instead of large-volume crystalloid fluid resuscitation. Finally, evacuation strategies that call for more highly-skilled medical providers during transport and minimized transport time to definitive care have gained wide acceptance. The combination of these prehospital measures (with improved definitive care, advances in strategic evacuation, and improvements in personal protective equipment) have produced unprecedented casualty survival rates in the conflicts in Iraq and Afghanistan. Many of these strategies are also gaining increased acceptance in civilian trauma systems. Every Ranger went to war in Iraq and Afghanistan equipped with a tourniquet and trained in its use. Preventable deaths from failure to obtain prehospital control of extremity hemorrhage throughout the recent decade of conflict have been zero. Two publications were instrumental in bringing about the widespread adoption of tourniquets to control extremity hemorrhage from vascular trauma by the U. Army Institute of Surgical Research describing the laboratory evaluation of commercially available tourniquets made specific recommendations about which tourniquet would best suit troops for use on the battlefield. Evaluation and testing of updated models continues in the quest to refine tourniquet design. Specifically, these guidelines, last updated in October 2014, call for tourniquet use in the Care Under Fire Phase of Care (that phase of battlefield trauma care carried out in the presence of effective incoming fire) as follows7: 7. If the site of the lifethreatening bleeding is not readily apparent, place the tourniquet "high and tight" (as proximal as possible) on the injured limb and move the casualty to cover. If bleeding is not controlled with the first tourniquet, apply a second tourniquet side-by-side with the first. Hemostatic dressings should be applied with at least 3 minutes of direct pressure. Do not delay in the application of the junctional tourniquet once it is ready for use. Apply hemostatic dressings with direct pressure if a junctional tourniquet is not available or while the junctional tourniquet is being readied for use. If it is, replace any limb tourniquet placed over the uniform with one applied directly to the skin 2-3 inches above wound. If bleeding persists or a distal pulse is still present, consider additional tightening of the tourniquet or the use of a second tourniquet side-by-side with the first to eliminate both bleeding and the distal pulse. Limb tourniquets and junctional tourniquets should be converted to hemostatic or pressure dressings as soon as possible if three criteria are met: the casualty is not in shock; it is possible to monitor the wound closely for bleeding; and the tourniquet is not being used to control bleeding from an amputated extremity. Every effort should be made to convert tourniquets in less than 2 hours if bleeding can be controlled with other means. Do not remove a tourniquet that has been in place more than 6 hours unless close monitoring and lab capability are available. Expose and clearly mark all tourniquet sites with the time of tourniquet application. Over the first 5 years of the wars in Afghanistan and Iraq, 7 out of every 100 combat fatalities were due to hemorrhage from extremity wounds. Bleeding from these areas is often termed junctional hemorrhage as it arises from vascular structures in the transition area between the torso and the extremities. A broader description of junctional hemorrhage is provided in the following section; but for the combat casualty, once care has entered the tactical field phase, better security and more time mean that additional hemorrhage control options become available. For junctional hemorrhage, these options often include a form of topical hemostatic agents and dressings. During Tactical Field Care, expose the wound and reapply the tourniquet directly on the skin 2-3 inches above the bleeding site. Tighten the tourniquet or apply a second tourniquet side-by-side and just proximal to the first as needed to eliminate the distal pulse. This will help to decrease the risk of possible extremity damage due to tourniquet ischemia. If bleeding does not remain controlled using nontourniquet methods, retighten the tourniquet until bleeding is controlled and the distal pulse is extinguished; expedite evacuation. Most humans with such an injury will exsanguinate in about 10 minutes, but some will bleed to death in as little as 3 minutes. Both the casualty and the corpsman/medic are in serious danger while a tourniquet is being applied in this phase. The decision regarding the relative risk of further injury versus that of bleeding to death must be made by the person rendering care. No significant exothermic reaction was noted with either Combat Gauze or Woundstat. Combat Gauze also has the advantage of being a gauzetype agent rather than a granular one. Based on their field experience, combat medics, corpsmen, and pararescuemen on the Committee on Tactical Combat Casualty Care expressed a preference for gauze over a granular agent. Granular agents also present an ocular hazard when used in high wind conditions (caused by transport in or downdraft from evacuation helicopters) and may be problematic to remove from wounds during subsequent operations. Combat Gauze should be applied with 3 minutes of sustained direct pressure over the bleeding site in order to be effective. More advanced hemostatic agents may become available in the future, and it is useful to have a standardized bleeding model with which to evaluate these agents. New agents should be tested using this standardized model so that their relative efficacy to Combat Gauze may be objectively evaluated. The vasculature considered as "junctional" involves the axillary, proximal femoral/distal iliac, and carotid arteries. The compressing surface is tightened with a screw mechanism, and counterpressure is exerted from the portion of the clamp that is applied to the posterior surface of the body. This technique works even with bleeding from major vessels such as the carotid or femoral arteries. Direct pressure is best applied with the patient on a firm surface so that effective counterpressure is present; for major bleeding, the pressure must be sustained until the casualty reaches a location where surgical repair of the vessel can be performed. Direct pressure is difficult to maintain while the casualty is being carried or transported on a litter, although consistent selfapplied direct pressure may be used successfully, even in carotid injuries. For these reasons, tourniquets and hemostatic agents are the preferred methods for control of life-threatening external hemorrhage on the battlefield. Noncompressible Hemorrhage Internal hemorrhage resulting from vascular disruption from chest and/or abdominal wounds is referred to as noncompressible torso hemorrhage. Noncompressible torso hemorrhage may result in shock and subsequent death despite a relatively unimpressive entrance wound. Transport of the casualty with penetrating trauma to the chest or abdomen should be accomplished on an emergent basis. Development of new methods of resuscitative aortic occlusion and mechanical hemostasis for noncompressible torso hemorrhage are the focus of current U. Defense Advanced Research Projects Agency and Department of Defense research efforts. The development of hypothermia is not merely due to exposure to a cold environment but can also occur in warm ambient temperatures as a sequela of hypovolemic shock resulting in decreased ability to produce heat to maintain body temperature. Shock predisposes victims to hypothermia and can contribute to worsening of the hypovolemic state as a result of ensuing coagulopathy. In this analysis, the focus was on 1063 patients where death was due to hemorrhage. At 1 to 3 hours after injury, there was also a significant decrease in mortality (4. Use of this solution permits smaller-volume (hypotensive) resuscitation than with standard crystalloid solutions. Blood products are the preferred fluid for resuscitation from hemorrhagic shock when they are logistically feasible. In the Tactical Field Care phase of casualty care, however, blood products are typically not available to most U. In that circumstance, Hextend is the preferred fluid, followed by Lactated Ringers and PlasmaLyte A solutions. Hetastarch has also been associated with increased renal injury and mortality; although in this report use of hetastarch was limited to the hospital (rather than the prehospital) domain, hetastarch patients were more severely injured than the nonhetastarch population; and no defined resuscitation protocol was in place for patients with hypovolemic shock. Special Operations Command Surgeon who noted that Special Operations forces must often operate in immature theaters and austere environments far from fixed medical care facilities. Assess for hemorrhagic shock (altered mental status in the absence of brain injury and/or weak or absent radial pulse). If shock recurs, recheck all external hemorrhage control measures to ensure that they are still effective and repeat the fluid resuscitation as outlined above. These platforms typically carry no offensive weaponry and are marked with a Red Cross. Training evacuation flight crews to the critical care flight paramedic level was associated with better outcomes, with a 48-hour mortality of 7. This platform would have an Emergency Medicine or Critical Care physician-led team 2. There is a Secretary of Defense directed 60-minute maximum time for evacuation, but faster transport to optimal care may be lifesaving for critical casualties. A Hostile Fire Evacuation Option should be identified in the mission planning phase to avoid evacuation delays due to ground fire. Armed, armored aircraft with no Red Crosses should be planned for if necessary and modular medical packages may be employed on these airframes. Limit the amount of crystalloid infused and use hypotensive resuscitation with Hextend if no blood available. These guidelines are evidence-based, reviewed on an ongoing basis and modified as necessary. Not all services need to be provided, but all service casualties should receive the same quality of care. The short-term goal is better resuscitation fluids to avoid exsanguination and severe ischemia with special emphasis on improving coagulation status. The longerterm goal is to explore mechanical means of hemostasis for penetrating, nonextremity trauma, from external compression of blood vessels. Eastridge B, Hardin M, Cantrell J, et al: Died of wounds on the battlefield; causation and implications for improving combat casualty care. Owens B, Kragh J, Wenke J, et al: Combat wounds in Operation Iraqi Freedom and Operation Enduring Freedom. Martin M, Oh J, Currier H, et al: An analysis of in-hospital deaths at a modern combat support hospital.