bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prolonged QT Syndrome
Authors: Ferguson Kris , Papapetrou Peter 
Published: March 2023

Abstract
Long QT syndrome is an uncommon condition and, if left untreated, can be a life-threatening condition. Patient presentation can range from asymptomatic to sudden death. The typical presentation is in younger patients, with symptoms ranging from asymptomatic to mild palpitations to cardiac arrest. Treatment is proportional to symptomatology. Outpatient medication management is directed toward minimizing factors that increase sympathetic output and β-blockade. More invasive management such as with defibrillators are life-saving for severe symptomatic disease. Anesthesia management is directed toward avoiding agents that prolong the QT interval, keeping the patient comfortable by avoiding loud noises, and minimizing pain and anxiety.
CNS Drugs for Nonanesthetic Use
Authors: Sekhri Nitin , Hui Kevin 
Published: March 2023

Abstract
Anesthesiologists use several classes of medications that target the central nervous system (CNS) for nonanesthetic use to treat side effects, mitigate risk of complications and treat postoperative pain. In addition, many patients will be on chronic medications that are CNS active, and understanding anesthetic implications is of the utmost importance for the practicing anesthesiologist. Of particular importance are medications used to treat patients with chronic opioid use disorder, such as methadone, naltrexone, and buprenorphine. This chapter is an overview of CNS-active medications that are commonly used outside of the operating room that are imperative to know for the physician anesthesiologist.
α2-Agonists
Authors: Shah Nimit K. , Al-Jindi Piotr 
Published: March 2023

Abstract
The α2-receptors bind with norepinephrine (NE) and epinephrine (E) and inhibit the release of further NE and subsequent neural firing. The two potent α2-agonists used in practice are dexmedetomidine and clonidine. Dexmedetomidine is a specific α2-adrenoceptor agonist with sedative, anxiolytic, analgesic, and sympatholytic properties. It has minimal effect on respiratory drive, which is a key advantage. It has a quick onset and short duration of action. Currently, it has only been licensed for use in intravenous infusions in the intensive care unit (ICU) for 24 hours. If used more than 24 hours, rebound hypertension is common. Following a rapid intravenous bolus (especially a high dose), it shows biphasic blood pressure response of the initial short phase of hypertension (HTN) and subsequent hypotension. Usually, the bradycardia produced by dexmedetomidine is clinically insignificant but may be significant in elderly patients, patients with heart blocks or severe cardiac diseases, and patients using heart rate–slowing medications. It is useful as a premedication, adjunct in general anesthesia (GA) and regional anesthesia (RA), ICU and procedural sedation, monitored anesthesia care (MAC) sedation, treatment and prevention of emergence delirium and postoperative shivering, and chronic pain. Clonidine has been traditionally used as an antihypertensive agent but has been found useful as an adjunct in GA and RA because of its similar properties of sedation, anxiolysis, analgesia, and sympatholysis. Other uses include treatment of opioid-induced hyperalgesia; ethyl alcohol, opioid, and nicotine withdrawal, treatment, and prevention of emergence delirium; and postanesthetic shivering. Rebound HTN and biphasic responses are seen with clonidine as well.
Antidepressants, Antiparkinson Drugs
Authors: Latimer Dustin , Cornett Elyse M. 
Published: March 2023

Abstract
Antidepressants are often used for a variety of conditions, including depression, anxiety, chronic pain, poor energy, and various off-label applications, among others. Serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants, and monoamine oxidase inhibitors are all types of antidepressants that are available (MAOIs). In certain cases, MAOIs are used to treat Parkinson disease, which is a clinically recognized neurodegenerative disorder that affects mostly the elderly population. L-DOPA, another Parkinson medication, is a prodrug that converts to dopamine in the brain and enhances dopaminergic action by boosting dopamine levels in the brain. It is used to treat Parkinsonism and other neurodegenerative diseases.
Antiaspiration Medications
Authors: Shah Nimit K. , Rahman Abed 
Published: March 2023

Abstract
Pulmonary aspiration is a rare but serious complication of anesthesia that can be benign or lead to significant mortality and morbidity in the perioperative period; thus it requires careful consideration regarding prophylactic measures. Pulmonary aspiration is defined as inhalation of oropharyngeal or gastric contents into the respiratory tract. Inhalation of solid material can lead to physical obstruction, whereas the acidity of the fluid will lead to a pneumonitis. This chapter reviews patient, surgical, and anesthetic factors that need to be taken into consideration to assess the risk of aspiration. It also reviews the optimal timing and dosing of antiaspiration medications.
Parasympathetic Nervous System
Authors: Munoz-Allen Maria E. 
Published: March 2023

Abstract
The parasympathetic nervous system (PSNS) is the counterpart and complement to the sympathetic nervous system (SNS) in maintaining cardiovascular, gastrointestinal, and thermal homeostasis. While activation of the SNS elicits the “fight-or-flight” response, the PSNS is more closely associated with the maintenance of organ function by modulating and/or down regulating the responses of the organism to internal and external stimuli. By utilizing our knowledge and understanding of the pharmacology of the autonomic nervous system, as it relates to the interactions of various medications that are administered during the delivery of anesthesia, we can promote and maintain safety for patients in the peri-operative period.
Anatomy of the Nervous System
Authors: Cutler Timothy , Zaky Sherif 
Published: March 2023

Abstract
Nociception, from the Latin noci (harm or injury), is the neural response to a noxious stimulus. It involves a four-part physiologic progression: transduction, transmission, modulation, and perception. This process results in the interpretation of pain, or “an unpleasant sensory and emotional experience associated with actual or potential tissue damage,” as defined by the International Association for the Study of Pain. Nociception occurs via a series of neurons, termed first, second, and third order, to signal an encounter with a painful stimulus from the periphery to the cerebral cortex. Neurotransmitters are released at synapses to relay both excitatory and inhibitory signals between neurons. First-order neurons are located in the dorsal root ganglion and synapse, with second-order neurons in the ipsilateral dorsal horn. Second-order neurons ascend the spinal cord, usually via the contralateral spinothalamic tract, then synapse with the third-order neurons in the thalamus. Third-order neurons finally transmit the signal to somatosensory areas I and II in the post–central gyrus of the parietal cortex or to the superior sylvian fissure.
Musculoskeletal System
Authors: Money Sarah , Aiyer Rohit 
Published: March 2023

Abstract
The musculoskeletal system facilitates voluntary and involuntary movement and is a core component of functional capacity, strength, and endurance. Signals for motor function descend from the cortex through the spinal cord to the motor nerve and skeletal muscle, resulting in muscle cell depolarization and contraction. The neuromuscular junction is arguably the most important point in this communication circuit, as it is the site of many paralytics necessary in anesthesia, but interference with any part of the motor signal will result in akinesia. This chapter discusses the anatomy and organization of the nervous system as it relates to musculoskeletal function.
Drug Intoxication
Authors: Smith Sarah C. 
Published: March 2023

Abstract
Drug intoxication presenting as a change in mental status may occur following intentional use of a recreational substance, attempt of suicide, accidental or occupational exposure, or even as a result of terrorism or deliberate poisoning by a criminal actor. The anesthesiologist must be prepared to identify and manage many forms of toxicity, particularly in the emergent setting, when victims of toxicity require airway management and other invasive procedures. History, physical examination, and laboratory studies can often identify the substance to which the patient was exposed, such that an appropriate anesthetic plan can be implemented. Depending on the source of toxicity, ongoing intensive care management in the postanesthesia period may be necessary until symptoms are adequately controlled and neurological functioning has recovered. Intoxication secondary to drugs of abuse can significantly alter the response to anesthetics and analgesics, while pain management in these patients can be particularly challenging.
Air Embolism
Authors: Linares Samuel , Nasr Ned F. 
Published: March 2023

Abstract
A vascular air embolism (VAE) is the entrainment of gas or exogenous air from the operative field in the arterial or venous vasculature. The incidence of VAE varies from 10% to 97% depending on the surgical procedure, being more common in neurosurgery, orthopedic shoulder surgery, and gynecological procedures. The two most important factors determining the morbidity and mortality are the volume of air and the rate of accumulation. Small amounts of air have subclinical presentation, as most is absorbed in the circulation; moderate amounts can cause pulmonary hypertension; large amounts can cause right-side heart obstruction, ventricular collapse, and death. The clinical manifestations include arrhythmias, hypotension, cardiogenic shock, dyspnea, decreased end-tidal CO2, increased end-tidal nitrogen, seizures, and altered mental status. The main goals of treatment consist of preventing further air entry, reduction of air entrained, and hemodynamic support. The anesthetic considerations consist of proper assessment in the preoperative period, as well as optimization of patient positioning. In the operating room, a precordial Doppler is the most sensitive and least invasive monitor; other diagnostic methods include end-tidal nitrogen and drop of end-tidal CO2. During the postoperative period, the patient should continue to be monitored in an intensive care unit.
Fluid Management in Neurosurgery
Authors: Naftalovich Rotem , Denis Daniel 
Published: March 2023

Abstract
Fluid movement within capillaries can be conceptualized by the oncotic gradient model as per the Starling law. The blood-brain barrier in the central nervous system begets the osmotic gradient as the primary driving force. The goal of fluid management during neurosurgery should be euvolemia to maintain cerebral perfusion pressure and intravascular volume using iso-osmolar crystalloids. Hypo-osmolar solutions should generally be avoided to prevent worsening cerebral edema. Hyperosmolar solutions such as mannitol and hypertonic saline can be used to preferentially draw free water from the interstitial space into the vasculature, decreasing cerebral edema and improving surgical exposure. Glucose-containing solutions should be avoided as hyperglycemia is associated with worse neurological outcomes. Prevention of vasospasm in subarachnoid hemorrhage can be managed medically with nimodipine and fluid management, with hemodynamic goals favoring perfusion. This can be achieved by the traditional “triple H” therapy of hypervolemia, hypertension, and hemodilution, but care must be taken to avoid hypervolemia-related side effects: pulmonary edema, myocardial ischemia (from increased afterload), and hyponatremia. Traumatic brain injury patients can present with significant hemodynamic instability, which further complicates their resuscitation.
Stereotactic and Gamma-Knife Techniques, Deep Brain Stimulator Placement, Intraoperative Wake-Up Techniques
Authors: Kim Roy , Abd-Elsayed Alaa 
Published: March 2023

Abstract
Neurosurgical procedures can often involve unique challenges for the anesthesiologist as the surgeries can often involve new technologies and take place in non–operating room settings. Gamma-knife radiosurgery is a stereotactic procedure that often takes place in a remote location and can take anywhere from six to ten hours to complete. It has the advantage of avoiding nearby healthy tissue to a greater extent than traditional methods. Deep brain stimulators are also being utilized for more than simply Parkinson’s disease. These procedures, along with extensive spine surgeries, can sometimes require an intraoperative wake-up test. Understanding the unique challenges for these procedures can help facilitate prevention of complications and ensure optimal outcomes for patients.
Bronchial and Pulmonary Circulations
Authors: Brewer Jordan , Giordano Christopher 
Published: March 2023

Abstract
Deoxygenated blood flows to the lungs via the pulmonary circulatory system to offload carbon dioxide in exchange for oxygen at the alveolar surfaces. This refreshed blood is returned to systemic circulation to meet the body’s metabolic demands. The lungs also require a system of perfusion, called bronchial circulation. This complex web of dual circuits depends largely on pressure gradients between atmospheric and arterial systems to drive blood flow. Ventilation strategies and hemodynamic control can affect the regional blood flow and autoregulatory functions of the pulmonary vasculature. Anesthesiologists should understand its organization and implications on physiology as they can interact with and augment its function in the operating theater.
Effects of Imbalance on Electrolytes and Organ Perfusion
Authors: Maben Sarah 
Published: March 2023

Abstract
Acid-base regulation is primarily controlled by the lungs via alveolar ventilation and the kidneys via bicarbonate (HCO3−) resorption or excretion. The net acid excretion in the kidney equals the bicarbonate production. Other electrolytes are affected by the systemic pH and move intra- or extracellularly to compensate. At the cellular level, potassium (K+) is the predominant intracellular cation, with an intracellular concentration of 140–150 mEq/L and a serum concentration of 3.5–5 mEq/L. Normal serum sodium (Na+) concentration is 140 mEq/L and serum chloride (Cl−) concentration is 100 mEq/L. Disproportionate changes in serum chloride concentration relative to sodium concentration indicates an acid-base disorder. Changes to serum pH affect cellular metabolism, leading to ischemia, cell death, and decreased organ perfusion.
The Anion Gap and Metabolic Acidosis
Authors: Stayner Scott , Ferguson Kris 
Published: March 2023

Abstract
Acidosis generally is defined as an arterial blood pH (pHa) of less than 7.35. Metabolic acidosis is due to a decrease in bicarbonate [HCO3−]. The decrease in HCO3− usually occurs secondary to one or a combination of three processes: consumption to neutralize the pHa, wasting of bicarbonate through the kidneys or gastrointestinal tract, and dilution of the extracellular compartment. The typical response to metabolic acidosis in awake and healthy patients is an increase in respiration to eliminate CO2. However, under general anesthesia, the patient will not be able to mount a respiratory response. Calculating the anion gap will help in determine the underlying cause of the metabolic acidosis so that the appropriate corrective interventions can be performed.
Lung Function and Cell Processes
Authors: Prabhakar Amit , Warth Matt 
Published: March 2023

Abstract
Clinicians who work in the perioperative space need to have a solid fundamental understanding of pulmonary anatomy and physiology and the unique cellular processes that allow for gas exchange and enzymatic metabolism. Pulmonary anatomy can be divided into portions that either participate in gas exchange or those that do not participate in gas exchange, also known as dead space. The respiratory epithelium is composed of a unique group of cells called pneumocytes that help to facilitate gas exchange and maintain the integrity of the pulmonary architecture. Alveolar macrophages and dendritic cells also work to provide immunologic protection.
Restrictive Lung Disease
Authors: Samuel Binoy , Merkow Justin 
Published: March 2023

Abstract
Restrictive lung diseases range from intrinsic to extrinsic causes and are broadly defined as decreased lung volumes manifesting as a decrease in total lung capacity (TLC), forced expiratory volume in 1 second (FEV1), and forced vital capacity (FVC). Intrinsic causes are typically a result of increased scarring, inflammation, and stiffening of the lung as compared to extrinsic causes, which are a result of forces external to the lung limiting the ability of the lungs to fully expand. Preoperative consideration for these patients includes adequate workup and optimization and treatment of the underlying etiology prior to elective surgery. Intraoperative treatment includes lung-protective ventilation strategies, avoiding high lung volumes, limiting excessive FiO2, and mitigating extrinsic factors that are contributing or playing a role in restrictive physiology. These patients are at higher risk for postoperative pulmonary complications and should be managed with care in the postoperative setting.
Respiratory Adjuncts
Authors: McMaster Michelle 
Published: March 2023

Abstract
Respiratory adjuvants such as heliox, nitric oxide, epoprostenol, and perioperative steroids can be used to improve ventilation/perfusion mismatching in the perioperative setting. Heliox improves ventilation by affecting air density. Nitric oxide and epoprostenol are potent vasodilators that preferentially affect ventilated pulmonary vasculature when administered via inhalation. Intraoperative steroids reduce inflammation and edema in patients with traumatic intubations and bronchospasm and can also be used in patients with chronic obstructive pulmonary disease who take chronic oral steroids.
Choice of Anesthesia/Anesthetic Techniques in Thoracic Surgery
Authors: Bialorucki Callan 
Published: March 2023

Abstract
The thoracic surgery patient population and surgical techniques introduce unique physiologic considerations when devising an anesthetic plan. Premedication prior to induction of anesthesia can be utilized to mitigate the risk of perioperative bronchospasm. Induction agents should be chosen on a case-by-case basis, with considerations given to propensity for reactive airway complications and concomitant cardiopulmonary disease. Thoracic surgery often utilizes one-lung ventilation techniques, which can be accomplished with a double-lumen endotracheal tube or an endobronchial blocker. One-lung ventilation, hypoxic pulmonary vasoconstriction, avoidance of acute lung injury, and postoperative pain control all complicate devising an anesthetic plan for thoracic surgical patients and can be addressed in several ways.
Advanced Anesthesia Review
Authors: Mahboobi Sohail K. , Coplai Dillon B. 
Published: March 2023

Abstract
One-lung ventilation (OLV) is the technique of ventilating one lung while letting the other collapse, and the list of procedures it is used for continues to grow. Techniques include bronchial blockers, mainstemming single-lumen tubes (SLTs), and—most prominently—double-lumen tubes (DLTs). To choose a DLT size, the ideal technique involves measuring the left mainstem bronchus on chest x-ray or computed tomographic scan and using a table to select the appropriate size. OLV preoperative evaluations emphasize reviewing the patient’s airway and pulmonary function, including taking special note of relevant/pulmonary imaging as well as any available pulmonary function tests. Barring patient-specific requirements, OLV is typically performed with a balanced anesthetic technique. Placement technique (direct or indirect laryngoscopy or fiber-optic) depends on the patient’s anatomy, though a fiber-optic scope is always used to confirm appropriate placement. During OLV, the deflated lung is perfused but not ventilated, causing a shunt and ventilation/perfusion (V/Q) mismatch and a fall in arterial oxygenation. Hypoxic pulmonary vasoconstriction (HPV) is the body’s physiological response to divert pulmonary blood from hypoxic to ventilated alveoli. Hypoxia during OLV is common, and the anesthesia provider should be well versed in the techniques and interventions that can be used to treat it. At the end of the procedure, the patient should be evaluated according to extubation criteria. If postoperative ventilation is required, a DLT can be replaced with a SLT for postoperative ventilation.
Thoracoscopy
Authors: Dabaliz Al-Awwab Mohammad , Stachur Christina 
Published: March 2023

Abstract
Video-assisted thoracoscopic surgery (VATS) techniques are used for both diagnostic and therapeutic purposes across a variety of pleural diseases, pulmonary resections, and peripheral biopsies. Other nonpulmonary indications for VATS include cardiac and esophageal surgeries. This chapter describes the indications and anesthetics management for patients undergoing thoracoscopy. Included are the preoperative, intraoperative, and postoperative considerations that will help the anesthesia provider plan a safe anesthetic and avoid common complications. We also describe important aspects of lung isolation and one lung ventilation (OLV) which are both necessary for appropriate surgical exposure, including differences with open thoracotomies, and the stepwise management of hypoxia in OLV.
Postoperative Pain
Authors: Hussain Nasir , Weaver Tristan E. 
Published: March 2023

Abstract
Postoperative pain, if not treated sufficiently, may progress to a pathological chronic pain syndrome, leading to significant disability and suffering. Preemptive and early treatment has been shown to decrease the incidence of chronic pain down the road. Various medication classes, including opioids, serotonin norepinephrine reuptake inhibitor (SNRIs), tricyclic antidepressant, local anesthetics, α2-agonists, nonsteroidal anti-inflammatory drugs, N-methyl-d-aspartate receptor antagonists, and agonists-antagonists, are at the perioperative consultant’s disposal when treating pain. While most medications in the immediate postoperative period will be given intravenously, other routes of administration, such as oral, epidural, intrathecal, subcutaneous, transcutaneous, transmucosal, intramuscular, and interpleural, may be appropriate under certain circumstances. Adjunctive techniques and therapies, including transcutaneous electrical nerve stimulation (TENS), cryotherapy, acupuncture, and hypnosis, may also be used in order to relieve pain and minimize opioid dosing and side effects.
Ventilator Support and Extubation Criteria
Authors: Mori Benjamin B. G. , Akintorin Abayomi 
Published: March 2023

Abstract
Mechanical ventilation (MV) is a vital life support measure, but prolonged use is associated with morbidity. Indications include apnea, respiratory distress, hypoxemia, and hypercapnia. MV unloads the increased work of breathing and stops the development of acidosis with respiratory depression. There are no absolute contraindications, but tension pneumothorax, bronchopleural fistula, right ventricular failure, and hypovolemic shock are relative contraindications. A thorough understanding of the different modes of MV is essential for successful application. The common terms used with MV should be known, and efforts should be focused on MV liberation as soon as the patient meets criteria for safe extubation.