bluuebunny/crossref_metadata_2025 huggingface dataset:
Echocardiography
Authors: Mori Benjamin B. G. , Jindi Piotr Al
Published: May 2024

Echocardiography has demonstrated utility in the perioperative management of those patients with underlying cardiac disease and intraoperative transesophageal echocardiography is now standard in most major cardiac surgeries. There is also growing evidence for its use in the noncardiac surgical patient, including in the preoperative assessment of those patients with known or suspected cardiac valvular disease, and it is helpful in guiding management, postoperatively, in the ICU setting. In this chapter, the general indications, contraindications, and recommendations of perioperative echocardiography are discussed. Furthermore, the standard 20 transthoracic echocardiographic views, set forth by the American Society of Echocardiography and the Society of Cardiovascular Anesthesia, are summarized.
Pressure Transducers
Authors: Schlecht Kathy D.
Published: May 2024

Pressure transducers convert mechanical energy (pressure waveforms in fluid tubing) into electrical energy (electrical signal displayed as a pressure waveform). The displayed pressure waveform can be influenced by damping and resonance. Damping (overdamping) occurs when the mechanical energy of the pressure waveform is dissipated prior to reaching to the diaphragm of the pressure transducer, decreasing the amplitude of the displayed waveform. Resonance occurs when the frequency of the arterial pressure wave is augmented by the natural frequency of the oscillating transducing system, increasing amplification, ringing, and overshooting of the systolic blood pressure (underdamping). Transducers must be zeroed to ambient atmospheric pressure to set a “zero” reference point and leveled to align the transducer to a point on the body.
Warming devices and techniques
Authors: Guruswamy Jayakar , Rao Akshatha Gururaja
Published: May 2024

Mean core body temperature is 36.5°C–37.3°C. Effector response occurs at threshold temperature. Thermoregulation is altered during anesthesia, leading to perioperative hypothermia. Most anesthetics increase warm response and reduce cold response thresholds. Hypothermia (core temperature <36⁰C) is associated with impaired coagulation, increased transfusion requirement, wound infection, and cardiac complications. Perioperative heat loss mostly occurs via radiation and convection. Active warming devices and passive insulation are used to prevent hypothermia. Active warming includes forced air warming devices, resistive warming devices, circulating water mattress or garments, negative pressure water warming system, and radiant warmers. Forced air warmers are commonly used perioperatively. These work by convection, prevent radiant heat loss, can increase temperature by 0.7⁰C/hour, and are more effective when a larger surface area is covered. Passive warming includes cotton blankets, surgical drapes, sleeping blankets, and space blankets. Cotton blankets are simple, inexpensive, and are easily available. Layer of trapped air prevents up to 30% radiant heat loss.
Etomidate
Authors: Ferguson Kris , Papapetrou Peter
Published: May 2024

Etomidate is an intravenous anesthetic agent used for the induction of anesthesia. Etomidate can also be utilized for brief procedures such as reduction of dislocated joints, cardioversion, and electroconvulsive therapy. It has rapid onset of action and relatively quick offset of action due to redistribution. Etomidate is painful upon injection because of the propylene glycol in which it is dissolved. If cardiac stability is a concern, etomidate has minimal impact on the cardiovascular system and maintains cerebral autoregulation. Etomidate is often the induction agent of choice in emergency situations as there is limited respiratory depression, a lack of histamine release and in traumatic brain injury, and it decreases intracranial pressure. There is a common side effect of myoclonus upon injection. Adrenal suppression is also present, as etomidate inhibits adrenal enzymes.
Ketamine
Authors: Papapetrou Peter , Ferguson Kris
Published: May 2024

Ketamine was first synthesized to be used as a milder hallucinogenic than phencyclidine. It is an NMDA receptor antagonist that has several useful properties in perioperative anesthesia. It produces a dissociative anesthetic state that does not reduce ventilatory drive, unlike other intravenous anesthetics. It maintains hemodynamic stability due to its indirect sympathomimetic properties in most patients but can cause negative inotropic effects if a patient has reached their maximum catecholamine level. It is a bronchodilator and can be used during bronchospasm. Though it does have several benefits, it should not be used in patients with increased ICP or in those patients at high risk for PONV. Postoperatively, it can reduce pain and opioid use when infused at a low dose.
Preparation for Anesthesia/Premedication
Authors: Yao Caylynn , Peterson Elisha
Published: May 2024

Prior to the induction of anesthesia, a series of medications may be administered which are referred to as premedication. These medications are not considered a component of either the patient’s usual medical regimen or of the anesthetic. Rather, premedication is administered to reduce anxiety, initiate amnesia, control pain, decrease airway secretions and the risk of aspiration pneumonitis, and lower the incidence of postoperative nausea and vomiting. Depending on the patient’s comorbid conditions, beta-blockade and glucocorticoid therapy may be considered for premedication. Other medications used in the preoperative setting, such as erythropoietin in the setting of anemia, are less common in standard practice. Mainstay premedication in anesthesia is discussed.
Increased Cerebrospinal Fluid Pressure
Authors: Tian Ling , Nguyen Christina T.
Published: May 2024

This chapter discusses increased cerebrospinal fluid (CSF) pressure from pathophysiology to treatment. It includes a table of common causes of increased CSF pressure and discusses how this translates to increased intracranial pressure (ICP), lower cerebral perfusion pressure, and the consequences of elevated ICP on neurophysiology. It goes on further to give an overview of treatment methods for increased CSF pressure, including noninvasive, pharmacologic, and invasive measures such as lumbar puncture and continuous ICP monitoring.
NPO Status and Full Stomach
Authors: Nebergall Mallory , Albert Mazin T.
Published: May 2024

Aspiration of gastric or oropharyngeal contents during anesthesia administration is an adverse event with significant morbidity and mortality. Nil per os (NPO) guidelines were developed to decrease the presence of particulate matter, acidic contents, or gastric volume present at time of induction in attempt to reduce the risk of aspiration or complications related to aspiration. In addition, preoperative interventions such as gastric decompression via nasogastric tube and reducing the acidity of gastric contents with medications, as well as intraoperative techniques using rapid sequence intubation with/without the application of cricoid pressure, and placement of an endotracheal tube can be used in an attempt to reduce the risk of aspiration. In the event aspiration occurs, treatment strategies are broad, including supportive care, suctioning gastric contents, changing patient positioning, intubation with an endotracheal tube, or even antibiotic administration.
Neuroaxial Anesthesia in Obstetrics
Authors: Penner John
Published: May 2024

The neuraxial anesthetic techniques of subarachnoid block, epidural block, and combined spinal epidural are used extensively in obstetric anesthesia. These techniques can provide both labor analgesia and surgical anesthesia. They are safe, effective, and are low risk for both the patient and fetus. Each technique has advantages and disadvantages, and can be done using just local anesthetics, or local anesthetics combined with opioids. This chapter will discuss the role of neuraxial techniques in the management of the parturient patient, both during labor and delivery as well as cesarean section. The process of placing neuraxial anesthetics is discussed elsewhere in this book.
Stages and Signs of Anesthesia
Authors: Gotlib Daniel , Lawrence Melinda M.
Published: May 2024

An understanding of the stages and signs of anesthesia is important for medical personnel providing an anesthetic. Personnel administering an anesthetic must appropriately monitor the patient and confirm that the appropriate level of anesthesia and analgesia is being administered for the case at hand. Dr. Arthur Guedel was the first to take a systematic approach, monitoring and classifying the stages of anesthesia. The American Society of Anesthesiologists has developed specific definitions for general anesthesia and all levels of sedation and analgesia.
Techniques of General Anesthesia
Authors: Gluncic Vicko
Published: May 2024

General anesthesia is a state of unconsciousness accompanied by reversible amnesia, analgesia, hypnosis, muscle relaxation, and suppression of autonomic responses, and the patient is unable to respond to voice or painful surgical stimulus. It can be achieved by injection or inhalation of anesthetic agents (induction phase). Once the state of general anesthesia is achieved, it can be maintained by an anesthetic given intravenously or by inhalation (maintenance phase). The most common intravenous hypnotics are propofol, etomidate, thiopental, and ketamine, while sevoflurane, isoflurane, desflurane, and nitrous oxide are typical inhalation anesthetics. Painful stimuli are blocked by opioids (sufentanil, fentanyl, alfentanil, remifentanil), while immobility is achieved by neuromuscular blocking agents (NMBA; rocuronium, vecuronium, atracurium, cisatracurium, succynilcholine). The choice of which agents will be used for the induction and maintenance of general anesthesia depends primary on the state and characteristics of the patient (age, hemodynamic stability, specific diseases, risk of aspiration, potentially difficult airway), but the type of surgical procedure (surgical site, length, level of pain) also plays a role. In addition, the anesthesiologist can choose from several different techniques of general anesthesia: total intravenous anesthesia, total inhalation anesthesia, or balanced anesthesia.
Techniques for Managing Airway (Including Difficult Airway Algorithm)
Authors: Sharma Sahil , Sharma Archit
Published: May 2024

Airway management is critical and includes mask ventilation, laryngoscopy, endotracheal intubation, and extubation of the patient. Difficulty can be encountered at any of these stages, potentially resulting in significant complications. Airway management is an acquired skill that requires knowledge of various anatomical, physiological, pathological features in addition to various methods and tools developed for getting an airway. Thorough careful planning and preparation and a thorough preoperative assessment, one can reduce the potential for complications. The American Society of Anesthesiologists (ASA) developed and recently revised guidelines for the management of the difficult airway that focusses on strategies for intubation as well as alternative airway techniques that can be used when a patient with a difficult airway is encountered.
Trauma
Authors: Nebergall Mallory , Albert Mazin T.
Published: May 2024

The administration of anesthesia is not without risks. Most patients tolerate general anesthesia without any issues. Even those who do suffer from side effects or minor complications experience mild, transient symptoms that are easily managed, such as sore throat, nausea, vomiting, lacerations to lips/oral mucosa, hypotension, etc. Complications as the result of general anesthesia are often multifactorial, but human error accounts for a large portion of morbidity for patients and a source of liability for anesthesiologists. Epistaxis is a common complication of nasal manipulation, but the most common iatrogenic injuries involve the larynx, pharynx, esophagus, and eyes. Knowing common complications associated with specific surgery procedures, as well as the complications common to airway manipulation and how to properly and promptly identify complications, can help minimize the risk of physical injury to the patient while under anesthesia and sequela as a result of such injuries.
Burns
Authors: Mahboobi Sohail K. , Sohail Ramaiza
Published: May 2024

Burns are not uncommon, with approximately 486 000 burn injuries receiving treatment and more than 3000 deaths annually, according to the American Burn Association report. In first few hours, the initial shock phase is followed by generalized edema due to increased capillary permeability, and release of inflammatory substances. Replacement of intravascular volume, to keep perfusing vital organs, should start with balanced salt solutions and with monitoring of urine output, used as an indicator of adequate resuscitation. Certain formulas are used based on body weight and percentage of burn area to help calculate required fluids. Carbon monoxide and cyanide poisoning should always be suspected, particularly with signs of smoke inhalation. If patient requires anesthesia, lower doses of anesthetic agents should be used due to decreased circulating volume and decreased perfusion to liver and kidney. Over a few weeks, the hypermetabolic phase starts with protein catabolism and decreased immunity. Succinyl choline should be avoided after 24 hours of burn due to risk of hyperkalemia. Burn contractures can make airway management challenging. In this phase and due to the hypermetabolic state of the body, higher than usual doses of anesthetic agents may be required. With timely resuscitation and early surgical intervention, these patients have a survival rate of approximately 97%. This chapter discusses the pathophysiology and anesthetic management of burn injuries.
Malignant Hyperthermia
Authors: Patel Priyanka H. , Matteson David
Published: May 2024

This review chapter on malignant hyperthermia (MH) examines the epidemiology, genetic basis, and pathophysiology of this rare autosomal-dominant disorder. The role of ryanodine receptor 1 and the diagnostic options for MH are discussed, including genetic testing and the caffeine-halothane contracture test. The pathophysiology is examined in detail using an organ system-based approach including neurologic and neuromuscular, cardiovascular, respiratory, renal, gastrointestinal, hepatobiliary, and hematologic manifestations. As early identification of the disease is crucial, the common signs and symptoms are detailed, in particular tachycardia, hypercarbia, and a hypermetabolic state. Finally, anesthetic considerations are discussed, emphasizing proper treatment with dantrolene and associated supportive care.
Alpha-2 Agonists
Authors: Horvath Balazs , Kloesel Benjamin
Published: May 2024

The alpha-2 adrenoreceptor agonists clonidine and dexmedetomidine possess sedative and analgesic properties without significant cardiovascular or respiratory depression as side effects. That, along with the versatile routes of administration, has made them integral elements of sedation for various procedures and in the intensive care unit. They are effective adjuvants to general and regional anesthesia, as well as to multimodal acute and chronic pain control. This chapter reviews the key pharmacological and clinical information that guides the safe and effective utilization of clonidine and dexmedetomidine for the anesthesiologist.
Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)
Authors: Reilly Austin , Elmofty Dalia
Published: May 2024

Nonsteroidal anti-inflammatory drugs (NSAIDs) are commonly used for analgesia in the perioperative time frame. NSAIDs are classified as non-selective or selective cyclooxygenase 2 (COX-2) inhibitors. Some are available over the counter, while other formulations require a physician’s prescription. It is important for the anesthesiologist to be familiar with the physiologic and pathologic effects of NSAIDs to effectively manage their use in the perioperative setting. This chapter reviews NSAIDs classifications, mechanism of action, pharmacology, side effects, and anesthetic considerations. Various factors such as age and comorbidities should be considered when administering NSAIDs to avoid perioperative complications.
N-Methyl-D-Aspartate (NMDA) Receptor Antagonists
Authors: Leonard Ethan R. , Eckmann Maxim S.
Published: May 2024

N-methyl-D-aspartate (NMDA) receptor antagonists are a group of drugs used widely in medicine as anesthetics. These agents work by inhibiting the NMDA receptor, a glutamate and ion channel protein receptor, thereby providing analgesia, sedation, and amnesia. There are several NMDA receptor antagonist agents available with varied routes of administration, including intravenous, oral, and intramuscular preparations. These agents include ketamine, methadone, memantine, and dextromethorphan. These drugs have sympathomimetic effects, with ketamine being the most potent. Ketamine is the NMDA antagonist drug of choice for procedures that require conscious sedation or general anesthesia. It is also often used for acute pain management. NMDA receptor antagonist use for chronic pain management is a topic of interest for many researchers, but preliminary results are inconclusive and further research needs to be conducted.
Neuromuscular Complications of Anesthesia
Authors: Anand Suwarna , Prem Anand
Published: May 2024

Over the last several decades, with reduction in anesthesia-related perioperative mortality, the need to further optimize patient care by reducing morbidity has taken precedence. Recognition of the role of anesthetic agents and techniques on airway reflexes and airway protection can reduce the risk of pulmonary complications and aspiration. Postoperative myalgia has long been attributed to succinylcholine use, and techniques to reduce this mild though distressing complication has improved the perioperative patient experience. Over the past decade, there has been renewed interest in the role of residual neuromuscular blockade and its significant impact on postoperative morbidity and mortality. Recognition of optimal train-of-four monitoring sites, quantitative neuromuscular blockade monitoring, optimal timing of reversal agents, and newer reversal agents such as sugammadex have reduced the incidence of residual paralysis in the postoperative period, improving patient safety.
Temperature-Regulating Centers
Authors: Dwarki Karthik , McConnell Matthew
Published: May 2024

Temperature regulation is essential for maintaining cellular function within the body. Core body temperature is generally kept around 37°C, with small daily variations due to circadian rhythm and monthly changes in fertile women. Thermoregulation occurs in three phases: afferent thermal sensing, central regulation, and efferent response. Multiple neurotransmitters determine the overall temperature threshold. Maintenance of homeostasis is regulated through the hypothalamic-pituitary-adrenal axis, specifically within the preoptic area of the anterior hypothalamus. With respect to anesthesiology, it is this axis and its response to temperature changes that are downregulated, including in the settings of general anesthesia, monitored anesthesia care, and regional anesthesia (especially with neuraxial techniques).
Variations in Vertebral Configuration
Authors: Rausch Douglas K. , Abdallah Rany T.
Published: May 2024

Cervical, thoracic, and lumbar vertebrae differ in both shape and size, allowing for region-specific functions. There are characteristics that are considered typical for each section of vertebrae, and atypical vertebrae also exist among them. The cervical vertebrae allow for ample range of motion, and C1 serves as a study seat for the occiput. The thoracic vertebrae contain extra attachment sites for the ribs and are important for rotation of the spine. Lumbar vertebrae are large and link in a way that allows for flexion and extension. Knowing the key differences between the vertebrae is also important because they serve as anatomic landmarks for many regional anesthesia procedures.
Carbon Dioxide Transport
Authors: Sidagam Vasu
Published: May 2024

This chapter discusses the physiology of carbon dioxide transport in blood, emphasizing that its main form of transport is in the HCO3– (bicarbonate) form. The critical role of the RBC is pointed out. Differences in the arterial, venous, measured and calculated bicarbonate levels, and its reasons are highlighted. The role of the serum HCO3––H2CO3 buffer system is discussed. The chapter ends with perioperative implications of abnormal serum HCO3 values.
Non-Respiratory Function of Lungs
Authors: Cornwell Drew , Kohan Lynn
Published: May 2024

This chapter discusses the multiple functions of the lung beyond that of gas exchange. Physical barriers provide a first line of defense against inhaled particles and pathogens from the outside world. These materials are trapped and filtered within the lungs, along with endogenous particles such as circulating emboli. Defense mechanisms also include filtration of both endogenous and exogenous materials. Metabolic activity of the lungs can modify drugs as well as circulating hormones. The cytochrome P450 system in the lungs aids in this process. Additionally, the highly compliant pulmonary microvasculature can serve as a reservoir of blood that is adaptable to varied demands.
The Tracheobronchial Tree
Authors: Alpaugh E. Saunders , Kaye Alan D.
Published: May 2024

The tracheobronchial tree contains important airway structures that the clinical anesthesiologist should be able to identify and to manage. Endotracheal intubation and single lobe ventilation are just a few of the many airway techniques the anesthesia provider can use to keep the patient physiologically stable during surgical interventions. Proper endotracheal tube placement requires an extensive knowledge of the distal trachea, its surrounding structures, and their physiologic roles. Once these procedures are performed safely, the anesthesia provider can obtain accurate respiratory measurements and respond with appropriate actions. This chapter outlines relevant anatomical structures within the tracheobronchial tree and considerations for the anesthesiologist.
Normal ECG and Electrophysiology
Authors: Dakhlallah Nadeen , Manders Larry
Published: May 2024

The heart can be divided into a right and left pump, each consisting of an atrium and ventricle. The heart fills to eject blood to the rest of the body in a synchronized fashion. A series of electrical signals are generated that stimulate the muscle fibers of the heart to contract and relax, ensuring appropriate time for synchronous movement. An electrical potential (voltage) results in a directional flow (current) that can be quantified. This flow of current is large enough to be detected on the surface of the body as an electrocardiogram (ECG). This chapter summarizes electrical physiology of the heart and assessment/interpretation via transcutaneous monitoring by electrocardiogram.
Myocardial Contractility
Authors: Tobes Daniel , Manders Larry
Published: May 2024

Myocardial contractility represents the ventricles’ ability to contract and eject blood. There are two ways in which to modify contractility: in a length-dependent (increased preload) or length-independent fashion (inotropy). These processes are made up of a dynamic interaction of myosin to actin and well as intracellular Ca2+ concentration. This chapter summarizes myocardial contractility as it relates to the intrinsic electrical conductance of the heart, which facilitates its ability to pump blood and transport oxygen to the rest of the body.
Blood Pressure
Authors: Zanath Erica , Helou Mada
Published: May 2024

Blood pressure monitoring is essential in every anesthetic. ASA Standard II requires that blood pressure be measured at least every five minutes. Blood pressure is the pressure generated in the arterial system from cardiac contraction. It determines the perfusion to all vital organs. According to the American College of Cardiology and the American Heart Association, normal blood pressure is defined as systolic <120 mmHg and diastolic <80 mmHg. Both hypotension and hypertension can lead to end organ damage, making careful monitoring and control imperative. Blood pressure can be monitored using both noninvasive and invasive methods. Noninvasive blood pressure monitoring can be accomplished via palpation, Doppler, auscultation, oscillometry, and arterial tonometry. Of these methods, oscillometry is the most common perioperatively. Invasive monitoring is accomplished using an arterial line with pressure transduction. Measurement of blood pressure using an arterial line is considered the gold standard.
Baroreceptor Function
Authors: Vasant Kris , Fayyaz Ahmed Muhammad
Published: May 2024

In this chapter the authors discuss the various arterial and venous baroreceptors in the body. They describe the structure, function, and effects on the regulation of cardiopulmonary homeostasis, including heart rate, contractility, preload, and afterload. Anesthetic considerations have been mentioned in the clinical context of patient care, including carotid sinus massage.
Capillary Diffusion, Osmotic Pressure, and Starling’s Law
Authors: Hayden Andrew , Sharma Archit
Published: May 2024

In order to function, cells are required to move materials in and out of their cytoplasm via their cell membranes. Diffusion is the movement of particles from an area of higher concentration to lower concentration, whereas osmosis is movement of fluid across a semi-permeable membrane. The exchange of gases between the alveoli and the blood occurs by simple diffusion, i.e., oxygen diffusing from the alveoli into the blood and carbon dioxide from the blood. Starling forces (hydrostatic pressure and osmotic pressure) govern the passive exchange of water between the capillary microcirculation and the interstitial fluid. This chapter describes the various degrees of interaction of these forces that govern the movement of fluid and gases in the human body.
Antianginal Drugs
Authors: Sidagam Vasu
Published: May 2024

This chapter starts with a diagram showing physiological determinants of myocardial oxygen (O2) balance and points along the pathway where drug therapy effects this balance favorably. Three common classes of drugs, their mechanisms of action, side effects, and contraindications are elucidated. Finally, newer antianginal drugs are discussed.
Enhanced Recovery after Colorectal Surgery
Authors: Torres Patrick , Ghabra Hussam
Published: May 2024

Enhanced Recovery after Surgery (ERAS) refers to a set of evidenced-based protocols that are intended to optimize the perioperative surgical experience by attempting to minimize surgical stress and hasten time to return to baseline health status postoperatively. This perioperative technique necessarily requires a multidisciplinary team approach, including surgeons, anesthesiologists, nurses, physical therapy, occupational therapy, and social workers to be implemented successfully. It covers most aspects of the preoperative, intraoperative, and postoperative care, with the goals of standardizing care while improving outcomes and potentially lowering medical costs. The results of these evidenced-based protocols include a reduction in surgical complications and postoperative pain, improved surgical outcomes, and decreased hospital length of stay. While this strategy is utilized across many different surgical subspecialties, it has been long implemented and studied with respect to colorectal surgery. This chapter will cover the different elements of ERAS protocols with emphasis on anesthesia-related interventions.
Renin-Angiotensin-Aldosterone System
Authors: El-Sabbahy Marwa , Fikry Karim
Published: May 2024

Renin-angiotensin-aldosterone systems exist in various tissues throughout the body, including the kidneys, adrenal gland, cardiovascular system, and nervous system, where it may be involved in local regulation of vascular tone. Renin causes angiotensin to be cleaved into angiotensin I, which is then converted to angiotensin II via angiotensin converting enzyme. In addition to its potent vasoconstrictor effect, angiotensin II has other important hormonal and electrolyte effects that significantly alter fluid balance. Angiotensin II leads to a direct increase in Na reabsorption via the proximal tubules, as well as the release of aldosterone from the zona glomerulosa of the adrenal cortex. Renin-angiotensin system can be interrupted by angiotensin converting enzyme inhibitors as well as angiotensin receptor blocker, both of which can lead to prolonged hypotension if not withheld in the perioperative period, especially if large fluid and blood shifts occur.
Transfusion Indications
Authors: Scott Courtney L. , Boydston Elaine A.
Published: May 2024

Transfusion medicine is an evolving practice, and today the tendency is toward more restrictive strategies, including goal-directed transfusion. Red blood cell transfusions are administered to treat symptomatic anemia in order to increase oxygen-carrying capacity of the blood and oxygen delivery to vital organs. Red blood cells are generally indicated when the hemoglobin level is less than 7 gm/dL, but not when it is greater than 10 gm/dL. Patients with hemoglobin levels between 7 and 10 mg/dL may benefit from transfusion depending on their underlying medical comorbidities, or in the setting of signs of end organ ischemia or active bleeding. Fresh frozen plasma contains all the factors necessary for coagulation and is indicated to correct hypocoagulable states due to either quantitative or qualitative deficiencies of these factors. Pooled units of platelets from multiple donors or apheresis units obtained from a single donor are administered to treat thrombocytopenia or to correct qualitative platelet deficiencies. Lastly, cryoprecipitate contains an abundant amount of fibrinogen, as well as Von Willebrand factor and factors VII and XII, and is administered to correct hypofibringenemia and other specific factor deficiencies.
Blood Preservation and Storage
Authors: Watt Stacey , Bonsu Prince
Published: May 2024

The collection of blood from donors undergoes a rigorous screening process before storage. Prior to storage, anticoagulants and preservatives such as citrate phosphate dextrose (CPD) or CPDA-1 are added; the additive adenine is used in order to provide nutrients, prevent clotting, and help maintain the overall viability of the red blood cell during storage. Blood is often stored at a temperature of 4°C but can be stored at much colder temperatures with variable storage time that ranges anywhere from 21 days to 10 years from the time of collection, unlike platelets, which have a limited storage time of 5 days at 22°C.
Effects of Cooling and Heating
Authors: Syed Madiha , Chen Pinxia
Published: May 2024

Body temperature is tightly regulated within a few tenths of a degree Celsius by the hypothalamus; deviations of a few degrees can have a profound impact on cellular metabolism. The human body maintains an average core temperature of 36.5–37.5°C via signals to the hypothalamus. Patients can experience variations in temperature under both general and neuraxial anesthesia. Intraoperative hypothermia is more common than hyperthermia. The major mechanism of hypothermia in both general and neuraxial anesthesia is the redistribution of body heat from the core to the periphery. This chapter aims to explain the physiologic effects of cooling and heating, common causes, and management strategies in the perioperative period.
Preparation for Transfusion
Authors: Cheng Paul K. , Malik Tariq M.
Published: May 2024

This chapter reviews key concepts related to preparation for transfusion of blood products. In addition to discussing ABO typing, blood screening, and cross-matching of allogeneic blood products, it also describes unique situations which arise in clinical practice including use of uncross-matched blood for emergent situations of anemia/hemorrhage or coagulopathy, use of designated or directed donor blood products, and a comparison of the different types of autologous blood transfusion options, such as pre-deposited autologous donation, intraoperative and postoperative blood salvage, and acute normovolemic hemodilution. These salient topics are relevant to daily anesthetic practice and often tested on the American Board of Anesthesiology board examinations.
Hypothalamus
Authors: Powers Zack , Giordano Chris
Published: May 2024

In a normal physiologic state, the hypothalamus plays a role in coordinating endocrine function, regulating autonomics, consolidating environmental input, and managing temperature and appetite. Pathology involving the hypothalamus may lead to conditions requiring expertise for a safe anesthetic. Specifically, endocrine dysregulation, autonomic instability, autonomic dysregulation, and neurosurgical technique may require consideration of the hypothalamus in the differential diagnosis. Pathology regarding the hypothalamus may require preoperative optimization/anesthetic consideration due to hormone imbalance from prior radiation, infiltrative disease, or a tumor. Hypothalamus dysfunction may also manifest intraoperatively or postoperatively due to surgical manipulation, infection, trauma, or stroke.
Glucagon and Catecholamines
Authors: Torres Felipe Vasconcelos , Santos Lucas Costa
Published: May 2024

This chapter discusses the role of glucagon and epinephrine in the metabolic regulation of the human body with a focus on carbohydrate metabolism. Glucagon is secreted by the pancreas, while epinephrine is secreted by the adrenal medulla. Both are catabolic hormones that are able to promote glycogenolysis, gluconeogenesis, and ketogenesis, and reduce glucose uptake in order to make energy sources available to vital tissues and organs, which may be needed during fasting or when a stress response is induced. They also exert hemodynamic effects by interacting with β-adrenergic receptors in order to sustain perfusion of vital organs. Their actions are critical in the metabolic response to stress in order to maintain energy availability and homeostasis.
Shared Decision-Making
Authors: Hanna Joseph Salama , Saad Ramsey
Published: May 2024

Shared decision-making is a key component of patient-centered healthcare. It is a process in which clinicians and patients work together to achieve multiple goals that includes making decisions, selecting tests, treatments, and care plans. These selections are based on clinical evidence that balances the risks of such test or treatments and the most likely expected outcomes with patient preferences and values. Shared decision-making relies basically on both patient autonomy and informed consent. The chapter reviews few steps that can help providers with shared decision-making which can eventually lead to both providers and patients agree on a healthcare plan. They are adapted from the Informed Medical Decisions Foundation.
Eating Disorders
Authors: Goldstein Mark A. , Goldstein Myrna Chandler
Published: May 2024

Eating disorders in adolescents are psychiatric issues that also impair biopsychosocial functioning. The four principal eating disorders seen during adolescence are anorexia nervosa, bulimia nervosa, binge eating disorder, and avoidant-restrictive food intake disorder. The risk factors for an eating disorder include genetic, psychosocial, and environmental factors; bullying; weight-based teasing; obesity; stress; anxiety; social media; and the female gender. Individuals with gender dysphoria as well as those who may have endured abusive experiences during dating relationships may also present with disordered eating. During the COVID-19 pandemic, there were increasing numbers of adolescents presenting with restricting eating disorders. The treatment for an eating disorder is complex, lengthy, and best done with a team approach. Anorexia nervosa has the highest fatality rate for any psychiatric disease.
Substance Use
Authors: Goldstein Mark A. , Goldstein Myrna Chandler
Published: May 2024

Adolescence is a high-risk period for the use of substances; the vast majority of youth try alcohol during this time, and about half experiment with an illicit drug. A number of factors place adolescents at risk for substance use including depression, attention-deficit disorder, peer relationships, and a history of child abuse and neglect. The example set by parents is even more powerful than any genetic influences. Social media influences may also increase the risk for an adolescent to use substances. Research has demonstrated an association between adolescents who abuse substances and suicidal behaviors. The treatment for adolescents with substance use issues begins with screening, and this may be done at a routine medical visit. Individual and/or group therapy, especially with family involvement, are the first steps in treatment.
Problematic Internet Use
Authors: Goldstein Mark A. , Goldstein Myrna Chandler
Published: May 2024

As a result of new technology, problematic internet use (PIU) is a problem for a significant number of adolescents. Most adolescents spend more than 7 hours a day using media, but a subset of adolescents who suffer from PIU spent more than that online. There appear to be associations between PIU in adolescents and mental health issues including anxiety and depression. In addition, there is evidence that adolescents with PIU have an increased risk for self-injurious behaviors, suicidal ideation, and suicidal attempts. Parents need to set boundaries with their adolescents on the amount of daily screen time. In addition, parents should model the appropriate use of the internet and smartphones. Parents should also advise and monitor the areas that adolescents are allowed to visit online, especially gaming and social media sites.
Transgender Adolescents and Gender-Incongruence
Authors: Goldstein Mark A. , Goldstein Myrna Chandler
Published: May 2024

According to data from the Centers for Disease Control and Prevention, 1 to 2 percent of adolescents identify as transgender. Transgender adolescents appear to have a higher prevalence of mental health issues including anxiety, depression, eating disorders, and suicidality, and they have a higher risk for victimization from violence. In addition, there is evidence that transgender youth are more likely to be victims or perpetrators of cyberbullying. But social media platforms appear to have positive benefits for transgender adolescents as they develop a sense of community by visiting various sites. Studies have also determined that they experience stigma and discrimination in the health care system but also derive benefits. There is good evidence that gender-affirming care improves gender dysphoria, increases the sense of well-being of transgender individuals, and provides the opportunity for these youth to develop into well-functioning young adults.
COVID-19
Authors: Goldstein Mark A. , Goldstein Myrna Chandler
Published: May 2024

The COVID pandemic has had profound effects on the biopsychosocial domains of adolescents. Worldwide, over 10 million children and adolescents lost a parent or caregiver to the disease. Remote learning, lockdowns, and other restrictions led to increases in adolescents with obesity. Rising numbers of adolescents with depression, eating disorders, or suicidal thinking flooded the emergency rooms of hospitals. Learning suffered, especially in resource-limited schools. Increased social media usage led to further worries and fears of the pandemic as well as problematic internet use while displacing adolescents’ physical activities and sleep. Racism against Asians appeared to increase. One technological breakthrough due to the pandemic was telemedicine, which allowed clinicians to establish and continue care for most adolescents.
War
Authors: Goldstein Mark A. , Goldstein Myrna Chandler
Published: May 2024

The impact of war on adolescents may be life altering, ranging from immediate stress responses to increased risk for mental health disorders. The risks inflicted by war may have lifelong impacts on the adolescent’s physical, mental, and social well-being and developmental domains. Symptoms of anxiety and depression spike because of war, and in adolescents, exposure to war is related to development of posttraumatic stress disorder. Social media may enhance the resilience of adolescents during wartime. Unfortunately, the loss of a parent in wartime can be the most stressful trauma for an adolescent, and it is a strong predictor for psychopathology. Virtual reality games may have a role as a treatment modality for adolescents experiencing mental health issues from war.
Pain Genomics
Authors: Doshi Tina , Torrie Arissa
Published: May 2024

Due to a combination of both intrinsic (biological) and extrinsic (environmental) factors, pain vulnerability is highly variable across individuals. Intrinsic factors include genetics and genomics, which may be differentially influenced by extrinsic factors to create a unique biochemical profile that influences pain perception, processing, and treatment response. This chapter discusses hereditary pain conditions that inform understanding of pain vulnerability, as well as the genetic, epigenetic, proteomic, metabolomic, microbiome, and environmental factors (including pharmacotherapy) that can contribute to pain sensitivity, susceptibility, and response to analgesics. Consideration of these genetic and molecular factors can help identify patients vulnerable to pain and offer a precision medicine approach to pain treatment.
Pain in Older Adults
Authors: Kelly Lauren A. , Kuwata Caitlyn , Goldhirsch Suzanne , Fernandez Helen M.
Published: May 2024

Among older adults (aged 65 years and older), pain is a highly prevalent, disabling, and underrecognized condition that can be challenging to manage. This chapter presents a framework for assessing and treating pain that is based on the interactions between pain and physical functioning, mood, cognition, multimorbidity, and patient values. With a focus on these geriatric tenets, the chapter guides providers and interdisciplinary team members in the development of multifactorial pain interventions that address the unique risk factor profiles and patterns of health care needs encountered in older adults with multimorbidity, frailty, and disability. Relevant age- and disease-related changes are highlighted, and strategies for pain diagnosis and management are reviewed in depth. The chapter situates pain within the larger context of psychosocial and socioeconomic determinants of health, which vary significantly among older adults and shape pain experience and outcomes. Reflecting on the current state of affairs with a growing aging population, the chapter argues that the imperative to address the burden of pain is inextricably linked with larger efforts to support the independence and quality of life of older adults.
Vulnerability to Pain-Related Disability Following Occupational Injury
Authors: Tait Raymond C.
Published: May 2024

Despite legal and regulatory safeguards that mandate treatment for workers who have incurred painful occupational injuries, those workers frequently demonstrate a suboptimal response to treatment that renders them vulnerable to persistent, pain-related disability. This chapter applies a diathesis–stress perspective to patient- and system-related factors that render workers vulnerable to disability, both directly and in interaction with other factors. Particular attention is paid to systemic factors specific to workers’ compensation programs, including operational inefficiencies, challenges to effective patient–provider collaboration, and litigation-related complications. Patient factors of particular importance for injured workers include dysfunctional recovery expectations (both overly pessimistic and optimistic) and issues associated with perceived injustice (the perception of being treated unfairly). The chapter concludes with a discussion of ways that these factors can interact to heighten vulnerability to persistent pain-related disability, and it provides recommendations on the management of systemic obstacles and patient predispositions that militate against a more timely and effective recovery, citing changes enacted in the state of Washington as an example.
Pain at the End of Life
Authors: Gugsa Frey , Berninger Lauren E. , Wang Eric J. , Smith Thomas J.
Published: May 2024

Pain at the end of life is influenced by a complex interplay of a person’s physical, cognitive, social, and spiritual experiences throughout their life. End of life is commonly described as the phase of life when a person is living with, and impaired by, an eventually fatal condition. Individuals in need of pain care at the end of life represent a group at increased risk of vulnerability, often with a lower quality of life and inadequate end-of-life pain management. Several factors increase vulnerability at the end of life, including clinical, social, cultural, structural, and economical barriers. Geriatric patients particularly may be among the most vulnerable adults, with factors such as frailty, cognitive impairment, lack of social support, and loss of independence resulting in negative outcomes. End-of-life care is often interdisciplinary and brings a unique and holistic perspective to address the needs of patients and families. As part of the interdisciplinary team, palliative care addresses pain and symptom management to patients at all stages of serious illness through evidence-based practices. Yet, many patients and families continue to experience unmet pain and symptom management. Hence, inclusive and accessible end-of-life pain management can become possible through building on the existing strengths in palliative care and addressing existing barriers to ensure better outcomes. This chapter defines dimensions of pain at the end of life and identifies specific, evidence-based strategies to evaluate and provide end-of-life pain relief. It also reviews the challenges faced during end-of-life pain management and suggests best practices.
Pain and Mental Health
Authors: Bhatt Snehal , Armstrong Maya , Jacobsohn Vanessa
Published: May 2024

This chapter explores the interplay between pain, depression, and anxiety. The chapter begins by highlighting the co-occurrence of chronic pain, anxiety, and depression, along with the additive impact of these illnesses on a patient’s outcomes. The chapter then explores the shared vulnerabilities with complex interactions between chronic pain, depression, and anxiety. Given this overlap of prevalence and mechanisms, the chapter advocates for a multidisciplinary approach that aims to actively engage, educate, and empower the patient; create an accepting and nonstigmatizing environment; and treat these conditions in a holistic manner using evidence-based nonpharmacologic and pharmacologic interventions. Pertinently, the chapter provides a step-by-step description of the process of assessment and interventions in a patient with these co-occurring conditions.
Pain and Suicide
Authors: Cheatle Martin D.
Published: May 2024

Suicide has become a global epidemic. Suicide is the 12th leading cause of death in the United States. Certain populations are at high risk for suicide, including individuals who suffer from chronic pain. Many patients with chronic pain experience isolation, personal and vocational losses, and at times do not feel validated by family or their health care providers. Clinicians caring for patients with chronic pain should be cognizant of the risk factors for suicide. This chapter summarizes the current literature on pain and suicide, examines known risk factors and mediators, and discusses mitigation strategies to reduce the risk of suicidal ideation and suicidal behavior in patients with chronic pain.