Recent Advances in Anesthesiology

Trauma is one of the primary causes of death for patients under the age of 44. Traumatic injuries are “time sensitive” where initial interventions are based on physiological derangements, and classical signs and symptoms which commonly occur based on the mechanism and pattern of injury. The primary survey focuses on maintaining life with the assessment of airway, breathing, circulation with hemorrhage control, and evaluation of neurological disability. Once exposure is obtained and the patient is stabilized, a detailed history is obtained and a complete physical examination must be done. This is the secondary survey. Thoracic injury, abdominal, pelvic and extremity injury are evaluated as well as the possibility of traumatic brain injury. The initial management of acute traumatic shock follows well established guidelines with the principle focus being damage control in order to optimize the patient’s likelihood of a successful outcome.

Upper extremity blocks are becoming increasingly popular for Orthopedic and Ambulatory Anesthesia. Since pain originates from the periosteum, knowledge of osseous innervation is important for a successful block. Choosing the correct approach will allow one to successfully operate on the shoulder, clavicle and proximal humerus, or the distal humerus, forearm and hand. The risks associated with the blocks help determine the approach used. The interscalene and supraclavicular approaches have a high risk of diaphragmatic paralysis. The infraclavicular approach has a potential for vascular puncture and difficulty with external compression due to the depth of the vessel, and is usually contraindicated in patients with same side cardiac pacemakers. Axillary blocks should be avoided in patients who cannot abduct their arm.

The paravertebral nerve block (PVB) allows the blockade of mixed nerve roots after they leave the intervertebral foramina. This provides anesthesia and analgesia for a variety of procedures and conditions including: breast surgery, thoracic surgery (thoracotomies, thoracoscopies, VATS), multiple rib fractures, herniorrhaphies, abdominal wall procedures; and to provide analgesia and anesthesia in the presence of severe scoliosis, kyphosis or Harrington rods; and also to treat chronic pain syndromes. The principal contraindications remaon infection, major coagulopathy, neuropathy of unknown origin and patient refusal. The use of catheters permits a longer duration of therapy. Complications include possible pneumothorax, intraneural injection, epidural spread and local anesthetic toxicity. This is a very useful technique to master.

Lower extremity blocks provide anesthesia and analgesia for a variety of orthopedic, vascular and cosmetic procedures involving the hip, the thigh, the knee, the leg, the ankle and the foot. Lower extremity blocks include the femoral nerve block, (FNB), the sciatic nerve block, the popliteal sciatic nerve block, the saphenous nerve block, the posterior lumbar plexus block and the ankle block. A combination of lumbar plexus and sciatic block provides complete anesthesia of the lower extremity. The femoral nerve block is among the easiest, safest, and the most successful blocks to master. This block can provide analgesia for a fractured hip, a femoral fracture, knee arthroplasty and the harvesting of skin from the thigh. The popliteal block when combined with the saphenous block provides complete anesthesia below the knee. When the ankle block is performed above the malleoli, complete anesthesia of the foot can be achieved. The use of regional-lower extremity blocks helps to avoid the risks of general or neuroaxial anesthesia especially for those who are frail, debilitated, with multiple co-morbidities and cardiovascular risk factors. In addition, lower extremities blocks can provide significant post-operative analgesia. The blocks maybe performed with the use of the ultrasound or with peripheral nerve stimulation.

Vascular access is critical in managing the perioperative patient. In critical situations, establishing adequate vascular access is often difficult, invasive, and carries significant risks. Ultrasound is an invaluable tool in facilitating efficient and safe vascular access. Ultrasound helps to verify the presence, position and potency of the target vessel prior to the needle puncture and provides real time imaging of the needle throughout the vasculature (puncture process. The following chapter reviews the basics of ultrasound physics and machine knobology for optimizing image acquisition. The specifications of establishing central access – internal jugular vein, subclavian vein, axillary vein, and femoral vein; as well as obtaining arterial access are discussed in detail. Sources that are useful to continue one’s education are also included.

Uncontrolled hemorrhage from trauma, surgery, or post-partum is a major cause of death, but more people die from clotting, as heart attacks, strokes, or thromboembolism. The coagulation system underlies this complex interaction between bleeding and clotting. There are numerous blood components, biologicals, and drugs that affect bleeding and clotting; a basic understanding is requisite for successful perioperative care. This chapter provides an essential review of primary and secondary hemostasis and fibrinolysis, conventionally available tests of coagulation, common causes of hemorrhage, and commonly used anticoagulant drugs and platelet inhibitors. Finally, it discusses current concepts of the use of blood components to reverse coagulopathy and the transfusion reactions that can complicate blood therapy.

Anesthesia for obstetrical emergencies presents some of the most difficult decision making quandaries in anesthesiology due to the double considerations of both mother and fetus. Concerns for the mother often compete with concerns for the fetus. In the following chapter, several topics will be discussed including emergency cesarean section in patients with comorbidities such as asthma, morbid obesity and eclampsia. A cesarean section may have to be done without a spinal, epidural, or general anesthetic; that is a cesarean section done using only local anesthesia. Non-hemorrhagic emergencies during labor such as umbilical cord prolapse, breach presentation and shoulder dystocia are elaborated. Recommendations for hemorrhage- antepartum due to placenta previa, placental abruption, trial of labor after cesarean section, and uterine rupture; as well as those for postpartum- hemorrhage due to placenta accreta, increta, percreta, as well as uterine atony and uterine inversion are discussed. The pregnant patient undergoing nonobstetrical surgery presents with other challenges that are also addressed in the chapter.

CHILDREN ARE NOT SMALL ADULTS. In this chapter, we will discuss the resources and standards that must be in place, in order for community-based programs to be in a position to deliver quality anesthetic care to children. Patient and procedural selection policies, appropriate equipment, dedicated physical space, and knowledgeable and experienced providers are just some of what is required. Caring for children in a large children’s hospital, where the entire system is geared toward pediatrics, can test the most experienced pediatric anesthesiologist. Children have unique physiologic, pharmacologic, pathophysiology, and behavioral characteristics which change and develop throughout their lives. We will examine the pre-operative, intra-operative, and post-operative aspects that make pediatric anesthesia different from the perioperative care of adults. Additionally, we will provide an overview of the anesthetic management of some of the more common ambulatory pediatric procedures which may be encountered in the community-based practice such as; myringotomy and tympanostomy tube insertion; tonsillectomy and adenoidectomy; genitourinary procedures – circumcision, hypospadias repair, inguinal hernia repair, and orchiopexy; and foreign body removal.

Trauma is the leading cause of death between ages 1-44. The “Golden Hour” represents the need for quick, accurate, and efficient response which can lead to the improved morbidity and mortality. Even in the community hospital setting, practitioners should be current in BLS, ACLS and PALS. Common categories of injury are traumatic brain injury, and penetrating injuries. After the primary survey, stabilization, and secondary survey; prompt decisions should be made for the need to transfer the pediatric patient to a pediatric hospital and trauma center or to maintain care in the community hospital setting.