Although anesthesiology and endocrinology are two distinct branches of medicine, some recent breakthrough treatments have brought together both medical specialties, particularly those concerned with surgical sciences and critical care. Related to the use of various traditional surgical techniques, the lack of newer and safer drugs, the lack of monitoring tools, and the scarcity of critical care services in the past, managing patients with various endocrine disorders has always been perceived as being more difficult by practicing anesthesiologists.

Airway management is a vital component of administering anesthesia, allowing for the exchange of gases between the patient and the surrounding atmosphere. Difficult or unsuccessful management of the airway is a significant source of anesthesia-related morbidity and mortality [1]. As such, it is important for anesthesia providers to be adept at all aspects of managing the airway. A thorough understanding of the pertinent anatomy and physiology, the ability to use clinical evaluation to identify potential difficulties, and a mastery of interventional techniques and procedures are crucial to safe and effective airway management. This chapter presents a comprehensive overview of the elements related to effective airway management.

Pain in the critically ill patient is often underreported and misdiagnosed. Contributing factors include such patients not being able to express themselves due to invasive respiratory support or altered mental function. Pain management in the intensive care unit (ICU) can be challenging due to the severity of illness of critically ill patients. The benefits and risks of pain management techniques and medications should be weighed against the severity of the patient’s illness and their comorbidities, as well as the side effects of each technique and medication.

A regional block, also known as a localized block, is a type of anesthetic that blocks nerve transmission to prevent or alleviate pain. Regional anesthesia is the process of injecting an anesthetic substance into a peripheral nerve and inhibiting transmission to avoid or treat pain. It is distinct from general anesthesia in that it does not alter the patient’s level of awareness to alleviate pain. There are numerous advantages of regional anesthesia over general anesthesia, including avoidance of airway manipulation, lower dosages, fewer systemic medication adverse effects, shorter recovery period, and considerably less discomfort following surgery.

Kidneys are paired organs, the primary function of which is to excrete metabolic byproducts involving physiologic processes of filtration, reabsorption, secretion, and excretion. The nephron forms the basic functional unit of kidneys and are primarily involved in urine production, excretion of metabolic waste, maintaining serum osmolality, and acid–base homeostasis. All these physiologic processes involve neurohormonal mechanisms and transporters.

Pediatric anesthesiology is a distinct subspecialty of anesthesia. It focuses on the perioperative care of preterm and term neonates, infants, children, and teenagers. The pediatric population is vastly different from adults, as the clinician must recognize variations in anatomy, physiology, pharmacodynamics, and pharmacokinetics. For example, infants and children under 3 years old have a greater rate of morbidity and mortality associated with anesthesia than adults [1, 2]. The American Society of Anesthesiologists Closed Claims Project reports almost half of malpractice litigation involving pediatric injuries have been related to adverse respiratory events associated with improper oxygenation and/or ventilation. It is important for anesthesiologists caring for children to have a detailed knowledge of the distinctions between pediatric and adult patients. This chapter will discuss anatomic, physiologic, and pharmacologic distinctions, as well as infection prevention and anesthetic considerations, in the pediatric population.

General surgical procedures encompass a multitude of surgical types. For the purposes of this chapter, the focus will be on anesthetic considerations for different types of esophageal, abdominal, intestinal, and peritoneal surgery, as well as colorectal surgery. In addition, common surgical techniques used for general surgical procedures to include in open, endoscopic, laparoscopic, and robotic surgery will be discussed.

Selection of the anesthetic technique to be employed during a procedure begins during the preoperative evaluation with consideration of factors such as the patient’s comorbidities and preferences and the type of procedure to be performed. Oftentimes, general anesthesia is not necessary and the procedure can be performed under a lesser depth of sedation. Procedural sedation is a technique that allows the patient to tolerate the discomfort of a procedure while still maintaining cardiorespiratory function. In order to accomplish this, the anesthesia provider administers sedative, dissociative, and/or analgesic agents alone or in combination [1].

The anesthesia workstation, commonly referred to as the “anesthesia machine,” is a complex and very specialized piece of equipment that is relatively unique in medical practice. It is, in essence, a device to control the delivery of medical gases to patients, including oxygen, air, nitrous oxide, and volatile anesthetics, along with a specialized ventilator adapted to operating room conditions. The safe use of the anesthesia workstation requires proper training, preuse checkout, and continuous monitoring of its function. The medical literature is replete with examples of patient harm from inappropriate use of the anesthesia workstation and from mechanical or electrical failure of its components. Additionally, volatile anesthetics, while valuable in medical practice, have a very low therapeutic index and manifest severe, and even fatal, side effects when administered improperly. Finally, many patients under general anesthesia are paralyzed for surgery and ventilated through an endotracheal tube. Their safety is completely dependent on the anesthesia professional’s use of the anesthesia workstation to deliver breathing gases, remove carbon dioxide from exhaled gas, and precise administration of volatile anesthetics.

The intercostal nerves are the continuations of the ventral ramus of the thoracic spinal nerves. To perform an effective ICB, the block should be performed proximal to the mid-axillary line, where the lateral cutaneous branch takes off. ICBs can be performed using landmarks, a nerve stimulator, or under ultrasound guidance. Evidence supports the effectiveness of ICBs for chest tube placement, rib fractures, and procedures of the breast and chest wall. Limitations of ICBs include the need to perform blocks at multiple levels (each level of fractured rib) and their association with a shorter duration of action, compared to other chest wall fascial plane blocks such as pectoralis (PECS) II block and serratus anterior plane block (SAP). This is mainly related to a high rate of absorption of local anesthetic within the intercostal space. These considerations make ICBs a less favorable option, as with each injection, there is a potential risk of complications, such as neurovascular injury and pneumothorax. The risk of local anesthetic systemic toxicity (LAST) may also be increased with multiple intercostal injections related to the highly vascularized bundle located underneath each rib, resulting in a high rate of absorption.

This is by far the most important aspect of preoperative assessment. Any patient with a score >2 should be referred to cardiology for additional testing. The Revised Cardiac Risk Index is shown in Table 16.1.

Preoperatively, the patient will transition from different depths of anesthesia, including the levels of sedation, to general anesthesia (GA). Sedation is a continuum of symptoms that range from minimal symptoms of anxiolysis to symptoms of moderate and deep sedation. Moderate sedation is defined by the patient remaining asleep, but being easily arousable. Deep sedation is achieved when the patient is only arousable to painful stimulation. GA refers to medically induced loss of consciousness with concurrent loss of protective reflexes and skeletal muscle relaxation. GA is most commonly achieved via induction with intravenous sedatives and analgesics, followed by maintenance of volatile anesthetics [1]. Table 9.1 lists the depths of anesthesia and associated characteristics.

Intravenous (IV) anesthetics were first discovered for their clinical utility in 1656 by Sir Christopher Wren, an architect, physicist, and astronomer at the University of Oxford while using a goosequill to inject opium into a dog to produce sleep [1]. In 1909, Ludwig Burkhardt became the first surgeon to deliberately use IV ether in a 5% solution to sedate patients for head and neck surgery, finding that a higher concentration caused thrombophlebitis and hemolysis, whereas a lower concentration proved too weak a sedative. The first barbiturate hexobarbital was used in 1932, soon being used for over 10 million cases by 1944. In 1989, the first propofol lipid emulsion formulation was launched in the United States, marking the beginning of the modern age of IV sedation pharmacology [2].