10 Anesthesia for Orthopedic Trauma

Orthopedic trauma surgeons realize the tremendous importance of coordinated care at trauma centers and by trauma systems. The anesthesiologist is an important link in the coordinated approach to orthopedic trauma care. “Musculoskeletal injuries are the most frequent indication for operative management in most trauma centers.” Trauma management of a multiply-injured patient includes early stabilization of long-bone, pelvic, and acetabular fractures, provided that the patient has been adequately resuscitated. (Miller, 2009) Early stabilization leads to reduced pain and improved outcomes. (Smith, 2008) Studies have shown that failure to stabilize these fractures leads to increased morbidity, pulmonary complications, and increased length of hospital stay. (Miller, 2009) “Life threatening and limb-threatening musculoskeletal injuries should be addressed emergently.” (Smith, 2008)


Introduction
Orthopedic trauma surgeons realize the tremendous importance of coordinated care at trauma centers and by trauma systems.The anesthesiologist is an important link in the coordinated approach to orthopedic trauma care."Musculoskeletal injuries are the most frequent indication for operative management in most trauma centers."Trauma management of a multiply-injured patient includes early stabilization of long-bone, pelvic, and acetabular fractures, provided that the patient has been adequately resuscitated.(Miller, 2009) Early stabilization leads to reduced pain and improved outcomes.(Smith, 2008) Studies have shown that failure to stabilize these fractures leads to increased morbidity, pulmonary complications, and increased length of hospital stay.(Miller, 2009) "Life threatening and limb-threatening musculoskeletal injuries should be addressed emergently."(Smith, 2008) The chapter will discuss the following orthopedic trauma anesthesia issues:


Pre-operative evaluation  Airway management including difficult airways and cervical spine precautions  Intra-operative monitoring  Anesthetic agents and techniques (regional vs general anesthesia)  Intra-operative complications (hypotension, blood loss, hypothermia, fat embolism syndrome)  Post-operative pain management

Pre-operative evaluation
Orthopedic trauma patients can be challenging for Anesthesiologists.These patients can range in age from young to the elderly, may have multiple co-morbid medical conditions, and even a previously healthy patient may have trauma-associated injuries that may have a significant impact on the anesthetic plan.The Anesthesiologist's role is to evaluate the entire patient, with particular focus on the cardiovascular, respiratory, and other major organ system function.All patients undergoing anesthesia for an orthopedic surgery require pre-operative evaluation.(Miller, 2009) The goal of pre-operative evaluation is to obtain pertinent information that may alter the response to anesthetic drugs and increase the risk of complications due to impaired tissue oxygen delivery.Medical complexity, as assessed by the American Society of Anesthesiologists (ASA) physical status, correlates with perioperative morbidity and mortality.

Class Description Class I
Normally healthy Class II Patient with mild systemic disease (e.g.hypertension) Class III Patient with severe systemic disease (e.g.heart failure,), nondecompensated Class IV Patient with severe systemic disease, decompensated (e.g., decompensated heart failure, respiratory failure, unstable angina, hepatic encephalopathy) Class V Moribund patient, survival unlikely with or without surgery Table 1.American Society of Anesthesiologists Physical Status (Miller, 2009)

Major organ systems
Age and functional status are useful in evaluating organ system reserves, and in determining sensitivity to anesthetic drugs.Patients with severe cardiac, pulmonary, hepatic, renal or neurologic disease are at increased risk for developing complications related to anesthesia, as are those with substance abuse and pregnant patients.(Miller, 2009)

Cardiovascular disease
Cardiovascular diseases including uncontrolled hypertension, ischemic heart disease, congestive heart failure, heart block, and arrhythmia increase the risk of anesthesia.Associated cardiac trauma may lead to low cardiac output due to tamponade, myocardial contusion, valvular disruption, and aortic dissection.Ischemic hypoxia and insufficient blood flow leads to cardiogenic shock and inadequate delivery of oxygen to the tissues.Any condition characterized by low cardiac output such as poor heart function, intense vasoconstriction, hypovolemia, or severe obstruction to blood flow should be optimized prior to surgery.Congenital heart disease may lead to intra-cardiac shunt and hypoxia.

Pacemakers and Internal Cardiac Defibrillators (ICDs)
If electrocautery is used in close proximity to an ICD or pacemaker, the electrical current generated can inhibit the pacemaker resulting in cardiogenic shock if the patient is pacemaker www.intechopen.comdependent.With an ICD device, use of the cautery may activate the ICD resulting in multiple shocks to the patient.The device itself may be damaged by electrocautery.Injury to cardiac tissue from current induced in leads imbedded in cardiac muscle may occur, leading to device failure.These patients deserve a cardiology consultation to properly manage the device.The ASA practice advisory recommends changing the conventional pacing function to an asynchronous pacing mode in pacemaker-dependent patients.The anti-tachyarrhythmia functions of ICDs, including the ability to provide defibrillation, should be suspended for the duration of surgery, assuming that electrocautery is required.After surgery, the device needs to be reprogrammed and function confirmed.

Respiratory disease
Patients with significant respiratory disease are at increased risk for pulmonary complications because of limited pulmonary reserve and because anesthetic drugs decrease the respiratory response to hypoxia and hypercarbia.This patient population develops hypoxia sooner than patients with normal respiratory function due to lower airway obstruction, lung tissue disease, inadequate alveolar-capillary transfer or intrapulmonary shunt.Respiratory failure may ensue, requiring post-operative mechanical ventilation.Chest trauma including pulmonary contusion, hemothorax, and pneumothorax may contribute to respiratory insufficiency.Pneumothorax may lead to shock if under tension, especially in the presence of positive pressure ventilation.Hemothorax may result in hemorrhagic shock (Smith, 2008) Hypoxemia-Decreased arterial oxygen tension Ventilation-Perfusion (V/Q) mismatch Diffusion impairment H ypoventilation

Hypercarbia -Increased arterial carbon dioxide (CO2) tension
Increased Dead Space Increased CO 2 production Disease affecting respiratory control centers Respiratory muscle weakness Increased respiratory muscle load Table 3. Causes of respiratory failure Causes of V/Q mismatch include interstitial lung disease, acute lung injury (ALI) or acute respiratory distress syndrome (ARDS), pneumonia, pulmonary edema, and pleural effusion.
Causes of hypoventilation include depression of the central nervous system by drugs, diseases affecting the brainstem, neuromuscular disease resulting in respiratory muscle weakness, and chest wall abnormalities.
Increased dead space occurs in conditions such as pulmonary embolus or emphysema.
Increased work of breathing due to impaired pulmonary compliance and increased pulmonary resistance may also contribute to respiratory failure.Increased resistance is due to bronchoconstriction, airway inflammation, or secretions in the airway.Decreased lung compliance may be due to pulmonary edema, pneumonia, fibrosis, or atelectasis.Decreased compliance can also be due to muscle or skeletal abnormalities of the chest wall or from intraabdominal processes such as ascites, distended bowel, or abdominal compartment syndrome.

Morbid obesity
Obesity has become epidemic in industrialized countries and is an important contributor to early death.Patients with a body mass index (BMI) > 40 are considered morbidly obese.The pathophysiologic consequences of obesity impact every major organ system, and increases both morbidity and mortality.(Miller, 2009)  OSA predisposes patients to airway obstruction, especially when sedated.Opioids are especially worrisome due to the potential for impaired control of breathing, post-operative apnea, and hypopneic episodes.OSA patients may require prolonged recovery in a monitored setting.The classic symptoms include daytime somnolence, a history of snoring, and apneic episodes while sleeping.Screening for OSA is routine.The apneic-hypopneic index is a useful measure of OSA severity and is obtained from polysomnography.Pulmonary hypertension, right ventricular failure and arrhythmias are not uncommon.S. Snoring -"Do you snore loudly (louder than talking or loud enough to be heard through closed doors)?"T. Tiredness during daytime -"Do you often feel tired, fatigued, or sleepy during daytime?"O. Stop breathing during sleep -"Has anyone observed you stop breathing during your sleep?"P. High blood pressure -"Do you have or are you being treated for high blood pressure?"B. BMI -greater than 35 kg/m 2 A. Age -older than 50 years old N. Neck circumference -greater than 40 cm (15.75 inches) G. Gender -male Table 5. STOP-BANG screening for OSA.High risk if positive for 3 or more of these 8 (Chung, 2008)

Liver disease
The liver is responsible for protein synthesis (albumin, coagulation factors, acute phase reactants), metabolism of carbohydrates, lipids, and amino acids, and drugs.The liver also has a role in immunity endocrine functions, red blood cell degradation and bilirubin excretion.The liver influences the plasma concentration and systemic availability of most drugs.The ability to metabolize and excrete IV anesthetic drugs may be significantly impaired in patients with severe hepatic disease.Common lab abnormalities include anemia, thrombocytopenia, elevated AST, ALT, alkaline phosphatase, increased PT and INR, and decreased albumin.(Miller, 2009)

Renal disease
Patients with kidney failure have multisystem abnormalities including neurological, cardiovascular, pulmonary, gastrointestinal, hematological, and musculoskeletal disease.Serum creatinine and blood urea nitrogen (BUN) are simple routine tests that are helpful as screening guides in management of patients with kidney impairment and provide a rough measure of glomerular filtration rate.The ability to excrete drugs may be significantly impaired in patients with end stage kidney disease.Anemia due to chronic disease, may contribute to hypoxia.Timing of dialysis and protection of dialysis access sites are important prior to surgery.(Miller, 2009)

Neurologic disease
Etiologies include traumatic brain injury, intracranial hypertension, infection, seizure disorder and neuromuscular disease.Dementia, delirium, confusion, poisoning, drug overdose, substance abuse, and metabolic disorders alter the clinical picture of neurologic disease.Neurologic disease can result in a disordered control of breathing, abnormal respiratory patterns, decreased minute ventilation and increased risk of hypoxemia.Patients with acute spinal cord injury may have impaired respiratory and cardiovascular function and present with neurogenic shock.Autonomic dysreflexia occurs in patients with chronic spinal cord injury.In these patients, stimuli below the level of spinal cord transection elicit increased reflex sympathetic activity over the splanchnic outflow tract without the normal descending inhibitory modulatory impulses due to blockade at the level of injury.The response is severe vasoconstriction below the level of transection, but vasodilation and bradycardia above the injury.The syndrome occurs most commonly when the lesion is above the T6 level.Stimuli such as bladder or intestinal distention can cause persistent hypertension, headache, visual changes, sweating, bradycardia and arrhythmias.If untreated, autonomic dysreflexia may cause stroke, seizure and death.

Elderly
Elderly patients have limited physiologic reserves.Illnesses tend to accumulate in both frequency and severity with age.Coronary artery disease, hypertension, and heart failure are more prevalent.There is a decreased heart rate response to hypovolemia due to decreased beta-adrenergic activity.The prevalence of atrial fibrillation is increased.Ventilatory responses to hypoxia and hypercarbia are reduced.The lungs lose their elastic recoil with aging and there is an age-related reduction in vital capacity and minute ventilation.Respiratory muscle strength consistently declines with age.Decreased chest wall www.intechopen.comcompliance and increased alveolar dead space increase the work of breathing.There is an increase in V/Q mismatching, alveolar dead space, and right-to-left transpulmonary shunt.Cough is less vigorous and there may be impaired swallowing reflexes, decreased secretion clearance, and increased incidence of pneumonia.Age-related central nervous system changes predispose the elderly to delirium and ICU psychosis.There is increased vulnerability to cerebral ischemia associated with hypotension.Renal and hepatic functions are reduced.The aging kidney has a decreased ability to dilute and concentrate urine and is vulnerable to nephrotoxins.The volume of distribution for anesthetic drugs is altered due to decreased lean body muscle mass.Serum protein production, including albumin, is decreased.Malnutrition and anemia are common.

Pediatrics
The pediatric age group covers a broad range of physiology and sizes, from newborn infants to adolescents.Infants are more dependent on heart rate to maintain an adequate cardiac output.They are unable to increase their stroke volume to the same extent as adults.Pediatric patients also have relatively high vagal tone and may develop bradycardia in response to vagal stimulation or hypoxia.Children have a higher incidence of upper respiratory tract infections and asthma which may contribute to increased risk of laryngospasm and bronchospasm.History of latex allergy or sensitivity should be specifically obtained since there is a large cohort of potentially latex allergic pediatric patients.Congenital heart disease and specific syndromes need to be documented and appropriately managed.

Previous anesthetics
Previous adverse experience with regional, general and nerve block anesthesia should be documented, especially with regards to cardiac arrest during anesthesia, unplanned ICU admission and difficult airway management.Malignant hyperthermia (MH) is a lifethreatening pharmacogenetic disease resulting from exposure of a susceptible patient to a trigger agent.It is characterized by rapidly increasing temperature (as much as 1ºC every 5 minutes), extreme acidosis, exaggerated CO 2 production, and muscle rigidity.The most common triggering drugs are succinylcholine and inhalation agents (halothane, isoflurane, desflurane, and sevoflurane).

Medications
Chronic medications should be continued with few exceptions (Table 6).Abrupt cessation of beta-blockers can produce undesirable effects such as rebound hypertension and arrhythmias.Patients on beta-blockers will not show the same degree of cardiovascular response to stress.Abrupt withdrawal of the alpha-2 agonist clonidine may result in severe rebound hypertension.
Long-acting oral agents for diabetes may lead to symptomatic hypoglycemia in a fasting patient.Oral diabetic medication should be discontinued prior to surgery and a finger stick glucose measurement should be obtained prior to initiating anesthesia.There are multiple types of insulin with differing half-lives, time and level of peak effect.
Patients with coronary artery drug-eluting stents should continue on dual antiplatelet therapy (i.e.clopidogrel, and aspirin) for at least one year following placement, and then continue indefinitely with at least one of those drugs thereafter.The risk of bleeding is increased.Individualized patient management is required to determine if the risk of coronary artery stent thrombosis and myocardial infarction is greater than the risk of perioperative bleeding.

Medication
Interactions The American College of Cardiology / American Heart Association guidelines recommend pre-operative cardiac testing in patients that are at increased cardiac risk, based on their clinical risk profile, functional capacity, and type of surgery.(Miller, 2009)

Chest X-ray
A chest X-ray is recommended for patients with: significant chest trauma, significant debilitating pulmonary disease history with no recent chest X-ray (within one year), significant change in pulmonary status within the past 6 months, or a recent pneumonia/ COPD exacerbation.(Fleisher, 2007) Computed tomography (CT) may also be indicated in patients with suspected aortic trauma.Smith, 2008)

Urine BHCG
Trauma in a pregnant patient is associated with a high risk of spontaneous abortion, preterm labor, and/ or premature delivery.The best treatment for the fetus is rapid and complete resuscitation of the mother.Serious trauma occurring in the first trimester of gestation can lead to birth defects or miscarriage secondary to the hemorrhagic shock with uterine ischemia, pelvic irradiation, or medication effects.A urine BHCG pregnancy test should be performed on all female orthopedic trauma patients of child-bearing age.(Miller, 2009) Trauma occurring in the second or third trimester of pregnancy requires an ultrasound evaluation.Fetal heart monitoring is indicated in the operating room if the fetus would be viable if delivered.Consider left lateral uterine displacement if possible for all patients in their third trimester to alleviate the compression on the inferior vena cava and resulting impaired venous return to the heart and hypotension.The obstetrician should be consulted immediately if it is determined that the patient is pregnant.(Miller, 2009)

NPO guidelines
The pre-operative fasting guidelines are written for healthy patients undergoing elective procedures requiring general anesthesia, regional anesthesia, and sedation.These guidelines do not apply for trauma patients, women in labor, or emergent surgeries, and do not guarantee complete gastric emptying.A trauma patient presenting for emergency surgery is considered to be a "full stomach" and is at risk for pulmonary aspiration of gastric contents with resultant pneumonia.(ASA Practice Guidelines, 2011) Reasons include ingestion of food or liquids less than 8 hours prior to the injury, swallowed blood from nasal or oral injuries, delayed gastric emptying associated with stress of trauma, and administration of oral contrast for CT.

Airway management
"Advanced trauma life support (ATLS) emphasizes the importance of the ABCDE mnemonic: airway, breathing, circulation, disability, and exposure."Verification of an open airway and acceptable respiratory mechanics are of primary importance, because hypoxia is the trauma patient's most immediate threat to life.The inability to oxygenate a person can lead to permanent brain injury and death within 5-10 minutes.Airway obstruction in a trauma patient can be secondary to: direct facial or neck trauma, hemorrhage of the nose, mouth, or upper airway, decreased consciousness, or aspiration of gastric contents/foreign body.Poor ventilation may be due to decreased respiratory drive, direct injury to the trachea or bronchi, pneumothorax, chest wall injury, pulmonary contusion, aspiration, cervical spine injury, or bronchospasm.(Miller, 2009)

Basic airway management
Airway management for any patient requires the proper equipment and medications.This becomes especially important in an emergency case.(Smith, 2008)  (Smith, 2008) Airway management begins with the proper positioning of the patient.Mask ventilation is usually the first technique used to ventilate a patient.Proper mask ventilation can be life saving.The face mask should be applied firmly to the face to ensure an adequate seal.A jaw-thrust maneuver (instead of the chin lift) should be used in any patient with a suspected cervical injury to help facilitate ventilation.The most common cause of airway obstruction during mask ventilation is when the tongue and epiglottis fall back in the supine/ unconscious patient.An oral airway or nasal airway (if not contraindicated) can help to open the airway.The rigid oral airway can cause gagging in a conscious patient resulting in vomiting and increased intracranial pressure.The nasal airway is usually better tolerated in an awake or semiconscious patient, but is contraindicated in certain facial fractures and basal skull injuries.(Smith, 2008) If the patient's airway exam is not predictive of difficult intubation, rapid sequence induction and intubation (RSI) is preferred following 3-5 minutes of preoxygenation with 100% oxygen.Cricoid pressure has been routine for most Anesthesiologists in an attempt to decrease passive regurgitation of gastric contents after sedation and paralysis.Recently, the value of cricoid pressure has been questioned due to its ability to distort the airway, displace the esophagus, and worsen the laryngeal view during intubation.In a traditional RSI, no attempts to manually ventilate the patient's lungs should be made until the endotracheal tube is secured in the trachea.If preoxygenation is insufficient (uncooperative patient, respiratory distress) or laryngoscopy proves difficult and oxygen desaturation occurs, mask ventilation should be done.Ventilation and oxygenation is the main priority.(Smith, 2008) (Smith, 2008) When performing RSI in a patient with hemorrhagic shock, etomidate and ketamine are preferred over propofol and thiopental due to less hypotension.Succinylcholine is the gold standard for paralysis due to its rapid onset and short duration.Undesirable side effects of succinylcholine include increased intragastric pressure, intraocular pressure, and intracranial pressure (ICP).Succinylcholine is associated with exaggerated potassium release in patients with certain neuromuscular disorders and burns and is contraindicated in patients with malignant hyperthermia.If succinylcholine is contraindicated, longer acting agents like rocuronium or vecuronium can be used to induce paralysis.The laryngeal mask airway (LMA) should be used whenever bag-mask ventilation is difficult.The LMA can alleviate ventilatory obstruction above the vocal cords.The LMA is not an effective device for periglottic or subglottic pathology, such as laryngospasm.The LMA is not a definitive airway and does not prevent aspiration in a trauma patient with a presumed "full stomach".(Smith, 2008) Rigid direct laryngoscopy is the most common technique used to place an endotracheal tube.If this technique is unsuccessful, then video laryngoscopy (e.g., Glidescope), flexible fiberoptic scope, or a surgical airway may be indicated.Help should be summoned as soon as the airway management plan is recognized as being difficult.(Smith, 2008)

Difficult airways
Common predictors of a difficult airway include: facial dissymmetry (trauma), tracheal deviation, cervical fractures, small mouth opening, inability to visualize the faucial pillars and uvula (Mallampati), limited neck range of motion, prominent incisors, distance between the thyroid cartilage and mandible < 6 cm, and a narrow maxillary arch.(Miller, 2009) If after performing an airway exam there is doubt about the ability to intubate the trachea following induction of anesthesia, consideration should be given towards securing the airway with topical anesthesia and mild sedation; induction agents and neuromuscular relaxants should be avoided before the airway is secured.If there is concern of airway injury (stridor, hoarseness, subcutaneous emphysema), spontaneous ventilation is maintained provided the patient is cooperative, stable, and is not in respiratory distress.A surgical airway or rapid sequence fiberoptic intubation may be necessary in these situations.If time permits, lateral neck radiographs, CT scanning, and endoscopy can be used to better define airway anatomy.In patients with difficult or compromised airways, choice of intubation technique is ultimately determined by skills, judgment, experience, available equipment, and urgency of the situation.(Smith, 2008)

Cervical spine precautions
Blunt trauma patients are assumed to have cervical spine injury until proven otherwise.Distracting injuries, intoxication, and altered mental status can make clearing the cervical spine difficult prior to proceeding to the OR for surgical management.The incidence of cervical spine injury is roughly 2% in patients with a closed-head injury and 2-6% for all blunt trauma patients.During direct laryngoscopy, the primary force applied is the extension of the occiput on C1 combined with flexion of the lower vertebrae.It is therefore possible to aggravate or worsen a cervical injury with the standard direct laryngoscopy approach.(Lovich-Sapola, 2010) Manipulation of the airway can exacerbate a spinal cord injury.Imaging studies of the patient's cervical spine should be reviewed prior to induction of anesthesia, if time permits.In patients with a known spinal cord injury and/or neurological symptoms, awake fiberoptic intubation is a prudent choice provided the patient is cooperative and adequate airway anesthesia can be achieved.A key advantage of a well performed awake fiberoptic intubation is the ability to document neurologic integrity after intubation, before inducing general anesthesia.In other patients, RSI with in-line cervical stabilization is preferred.(Smith, 2008)

How to clear a cervical spine
In an alert patient without intoxication, neck pain, decreased level of consciousness, distracting injury, or neurologic abnormalities, the patient's cervical spine can be cleared clinically.The patient's cervical spine can not be cleared even with the appropriate radiographs if they have a "distracting injury".A normal cervical spine X-ray does not rule out a cervical injury, because ligamentous injuries may not be recognized on an X-ray.A CT scan/MRI may be required to rule out the cervical ligament injury, and there is often no time to do this testing in a trauma situation prior to going to the operating room.(Lovich-Sapola, 2010) www.intechopen.com

In-line stabilization
The patient's occiput should be held firmly on the backboard or operating table to limit the amount of "sniff".Immobilization of the spine can be accomplished by an assistant providing manual in-line stabilization.A semi-rigid collar or sandbag placed on both sides of the neck and head can also help in maintaining the proper neck position.A well-fitted hard collar can make an intubation almost impossible and should be removed prior to any intubation attempt.Hold the patient's head in-line with the cervical spine to prevent any cervical twisting.Laryngoscopy will always be more difficult with cervical stabilization.

Pulse oximetry
The pulse oximeter uses two wavelengths of light: red (660 nm) and infrared (940 nm).The light is transmitted from one side of the sensor to the photodetector on the opposite side, through pulsatile tissue.Oxy-and deoxyhemoglobin vary in light absorption at different wavelengths.The measured wavelength absorption ratio is converted to percent oxygen saturation.(Smith, 2008)

Electrocardiogram
The electrocardiogram (EKG) is a measurement of the electrical activity of the heart.Whenever a patient is undergoing anesthesia they must have continuous EKG monitoring.
Limb lead II is used to monitor for arrhythmias and chest lead V5 is used to watch for ischemia.(Lovich-Sapola, 2010) There are multiple EKG changes that are common in a trauma patient.The EKG changes can be a result of metabolic derangements from hemorrhage and resuscitation, structural injury to the heart itself, or central nervous system injury.Trauma patients are also at risk for cardiac ischemia due to high circulating catecholamines in the potential presence of existing coronary disease.(Smith, 2008) Electrical activity to the heart does not guarantee perfusion, as seen in pulseless electrical activity (PEA).In PEA there is electrical activity to the heart, but no myocardial contraction.PEA can occur in multiple trauma scenarios including, cardiac tamponade, tension pneumothorax, hypovolemia, hyperkalemia, and hypothermia.(Smith, 2008)

Blood pressure monitoring
Blood pressure should be monitored at least every five minutes while a patient is undergoing anesthesia.Blood pressure can be monitored non-invasively or invasively.Noninvasive blood pressure monitoring requires the use of a manual or automatic blood pressure cuff.This technique is the one most commonly used.Complications of a noninvasive blood pressure cuff include compartment syndrome from overuse of the cuff and inappropriate treatment of erroneous blood pressure readings from the improper positioning/ placement of the cuff.(Lovich-Sapola, 2010) Hypothermia must be avoided in all cases, but especially trauma cases secondary to the resulting coagulation disturbances, cardiac arrhythmias, inappropriate diuresis, delayed drug metabolism, and increased risk of infection caused by prolonged hypothermia.The operating room should be heated for all trauma cases to >24 °C to help prevent further hypothermia.(Smith, 2008)

Central Venous Pressure (CVP) monitor
CVP is usually obtained by venous access in the internal jugular vein, subclavian vein, or femoral vein.The CVP is an indicator of preload, although there is wide variability due to compliance of the venous system and right atrium.Fluid status can be monitored by following CVP trends.(Smith, 2008)

Urine output
Urine output is a traditional tool used to guide fluid resuscitation in a trauma patient.Urine output is a reflection of organ perfusion.Approximately 0.5 mL/kg/hr is desired for urine www.intechopen.comproduction.Trauma patients should all be catheterized for accurate urine output evaluation.
If there is a concern of significant bladder injury from the trauma, a Urologist should be consulted.(Smith, 2008)

Anesthetic agents and techniques in the operating room
Many orthopedic cases are well suited for regional anesthetic techniques, but there is controversy over whether regional anesthesia has an advantage over general anesthesia.For many orthopedic trauma cases a combined regional and general anesthetic approach is optimal to incorporate the hemodynamic, analgesic, and anxiolytic benefits of each.(Miller, 2009) (Miller, 2009)

Goals of general anesthesia
Goals of general anesthesia consist of re-establishing and maintaining normal hemodynamics, maximizing surgical exposure, and minimizing complications.Hypotension is initially treated with fluids.Vasopressors may be required afterwards.Frequent evaluation of acid-base status, hematocrit, and urinary output is routine during major orthopedic trauma.Titration of additional anesthetics can be done if satisfactory hemodynamics.(Bassett, 2011) Hemodynamic instability may occur with an epidural/spinal anesthetic  Venous thromboembolism prophylaxis may limit the ability to safely perform the technique  Unknown patient anticoagulation status in a trauma patient may limit the ability to safely perform this technique  Placement may be difficult secondary to restrictions in positioning of a polytrauma patient Table 23.Advantages and disadvantages of regional anesthesia in an orthopedic trauma patient (Miller, 2009) (Smith, 2008)

Femur fracture
Femur fractures carry a mortality rate as high as 25%."Life threatening hemorrhage can occur with bilateral femur fractures or multiple long-bone fractures."The average blood loss from a femur fracture can be as high as 1,500 cc.Secure venous access is mandatory (e.g., two large bore peripheral IV catheters).(Smith, 2008) Early definitive stabilization of the femur fracture (within 24 hours of the injury) has been shown to be safe in most patients.This includes patients with multiple injuries such as severe abdominal, chest, or head injuries as long as adequate attention has been paid to resuscitation and medical optimization prior to surgery.(Nahm, 2011) This optimization should include fluid resuscitation with crystalloid, colloid, and blood products as needed.The patient should be followed with serial arterial blood gas samples to follow the lactate levels and pH levels to show if the resuscitation is effective.Early consultation with other services including Neurosurgery, General Surgery, Cardiology, Pulmonary, Renal, may be life saving for the patient.(Miller, 2009)

Pelvic fracture
Pelvic fractures are often caused by a significant trauma to the lower trunk and are "often accompanied by chest (21%), head (16%), and liver/spleen (8%) injuries".The three-month mortality of a pelvic fracture is around 14%. (Miller, 2009) The bleeding from a pelvic fracture is often into a closed space and therefore not immediately obvious to an examiner.Pelvic fractures can be associated with several liters of blood loss.Urgent resuscitation and early stabilization of the pelvic fracture can minimize the morbidity and mortality.(Smith, 2008) An arterial line and multiple large gauge venous catheters are recommended.(Miller, 2009) Pelvic ring fractures require immediate recognition and management by the trauma team.
Patients with a pelvic ring fracture are at a high risk for hemorrhage.Bleeding often occurs at multiple disrupted venous beds in the pelvis, and if the pelvis is unstable, there is no anatomic barrier to the continued expansion of this retroperitoneal bleed.Pelvic fractures can result in fatal retroperitoneal bleeding.Surgical exploration is usually not the required treatment.Successful treatment often includes volume resuscitation, external fixation of the unstable pelvis, and angiography.Intubation and anesthesia involvement is often required secondary to the associated hypotension and need for active fluid resuscitation.(Miller, 2009) Treating an unstable pelvic arterial bleed in angiography is not without risks.Angiography is often performed in remote locations in the hospital.The unstable patient would require transport to the angiography suite and then potentially to the operating rooms.An anesthesia team is often requested to accompany the patient in the angiography suite to perform continued monitoring, airway management, and resuscitation.The anesthesia equipment and monitors used in the remote location should meet the same standards as those used in the operating room.The Anesthesiologist must also have a reliable way to communicate for help if needed.(Smith, 2008) Most reports suggest that the optimal time for stabilization of a pelvic fracture is within one week of the injury.(Miller, 2009) Recent studies have shown that there are benefits associated with an early (within 24 hours of injury) stabilization or reduction and definitive fixation of an unstable pelvic fracture.These benefits include: control of bleeding, assist with resuscitation, pain relief, ability to mobilize the patient, ease of reduction, improved reduction quality, elimination of traction, elimination of recumbency, reduced risk of pulmonary, septic, and thromboembolic complications, less organ failure, reduced morbidity and mortality, decreased length of stay in the intensive care unit, and shorter overall hospital stay.(Vallier, 2010)

Hip dislocation
A hip dislocation is a medical emergency, often resulting from a high impact trauma.Failure to quickly diagnose and treat this injury can result in avascular necrosis of the femoral head and significant neurologic injury.A hip dislocation usually requires a very deep level of anesthesia to facilitate a successful reduction.While occasionally the hip dislocation can be reduced in a spontaneously breathing patient with a combination of midazolam, fentanyl, ketamine, and/or propofol, often they require a nondepolarizing muscle relaxant.If a trauma patient requires complete relaxation with a nondepolaring muscle relaxant, then the procedure should be performed in the operating room with full ASA monitors and an endotracheal tube secondary to the trauma patients increased risk of aspiration.Patients that present to the hospital and are inebriated, uncooperative, confused, hemodynamically unstable, or have pulmonary dysfunction, should also be intubated prior to a hip reduction.(Miller, 2009) 6.4 Hip fracture (femoral neck fracture) Hip fractures are most common in the elderly.They are associated with a significantly high morbidity and one-year mortality (30%).These patients often present in considerable pain, high stress states, and possibly exhibiting symptoms of myocardial ischemia.Early surgery (<12 hours) has resulted in: lower pain scores, decreased length of hospital stay, and reduced peri-operative complications.Compared with delayed surgery, there is no association with increased survival.Early surgery should be the goal for stable patients, combined with early mobilization, rehabilitation, and aggressive medical care.(Miller, 2009) Hip fractures can result in significant blood loss.The patients are often dehydrated and anemic.A normal intravascular blood volume should be restored prior to anesthesia and surgery.Placement of a central venous catheter and arterial line can guide the fluid management and help prevent congestive heart failure from over-resuscitation.(Miller, 2009) Peri-operative Complications of Hip Fractures  Cardiac complications: myocardial ischemia  Pulmonary complications: fat embolism, pulmonary embolism  Deep venous thrombosis  Delirium: secondary to dehydration and electrolyte abnormalities Table 27.Peri-operative complications of hip fractures (Miller, 2009) Patients undergoing a hip fracture surgery have the highest risk of death from a pulmonary embolism.A spinal anesthetic is recommended for the actual surgery, but an epidural is rarely indicated for post-operative pain management secondary to the aggressive postoperative anticoagulation that will be initiated.(Miller, 2009)

Open fracture
Open fractures are surgical emergencies.The infection rate increases after a delay of 6-8 hours.Debridement and irrigation in the operating room plus provisional or definitive fixation of the fracture should happen as soon as it is safely possible.Open fractures require cleaning, pulse lavage, and debridement as soon as possible to minimize the risk of infectious complications.If the patient is not stable enough to go to the operating room, this should be done at the bedside.(Smith, 2008)

Traumatic amputation
A traumatic amputation requires immediate treatment with pressure, control of the bleeding, early intravenous antibiotics, and tetanus prophylaxis.Emergent surgery is often necessary to control the bleeding and perform surgical debridement.(Smith, 2008)

Vascular injury
"Injury to the major arterial flow of a limb is a surgical emergency."It is most common after a penetrating trauma, but can be seen with blunt injuries.Traumatic knee dislocations are the most common etiology for a vascular injury in a blunt trauma.A major arterial injury should be suspected in a patient that presents with pallor, coolness, and decreased pulses of the extremity.The patient may also present with an expanding hematoma or massive bleeding.Blood and fluid replacement by the anesthesia team is critical for the patient's survival.(Smith, 2008) 7. Intra-operative complications

Hypotension
Hypotension can occur during any case in the operating room.In a trauma situation, it is especially important to consider a wide differential so that the true cause of the hypotension is not missed.Hypotension may be caused by hypovolemia: undetected or underestimated blood loss, insensible losses, gastrointestinal loss, renal loss, excessive venodilation, and redistribution of fluid to an extravascular space.All forms of shock including obstructive, cardiogenic, and vasodilated shock should be ruled out.(Smith, 2008)  (Smith, 2008) Resuscitation from shock refers to the restoration of normal physiology after injury.Resuscitation after a hemorrhagic shock requires the restoration of a normal circulating blood volume, normal vascular tone, and normal tissue perfusion.(Miller, 2009) Early resuscitation occurs while active bleeding is still ongoing.The goals in early resuscitation are to maintain the systolic blood pressure at 80 to 100 mmHg, maintain the hematocrit at 25-30%, maintain the coagulation panel and ionized calcium level within a normal range, keep the platelet count > 50,000, maintain the core temperature at > 35 °C, and prevent worsening acidosis.Late resuscitation is defined as after the bleeding is controlled and has separate goals that include maintaining the systolic blood pressure > 100 mmHg, maintaining a normal hematocrit, normalizing the coagulation status, electrolytes, temperature, and urine output, and maximizing the cardiac output.(Miller, 2009)

Significant blood loss
Patients with orthopedic injury and poly-trauma including orthopedic injury may present with a significant blood loss.Massive transfusion protocols (MTP) have been designed and implemented in many large urban trauma centers to provide a rapidly bleeding patient with automatic regular shipments of blood products to facilitate fluid resuscitation during an emergency surgery.The goal of the design ratio of packed red blood cells, plasma, and platelets built into the protocol are based on the need for volume support, oxygen delivery, and coagulation support required at each stage of the resuscitation.(Smith, 2008) When should the MTP be initiated?This is often a judgment call made by the Surgeon or Anesthesiologist.It can be guided by these criteria: 5-unit blood loss in one hour, or 10-unit blood loss anticipated for the entire case or within 12-24 hours of observation, or hypovolemic hypotension uncorrected by crystalloid and/or packed red blood cell resuscitation during an ongoing hemorrhage.(Smith, 2008) During the MTP, a cooler containing blood products is brought one at a time to the operating room as each is finished or until the MTP is terminated.The MTP will vary from hospital to hospital.See below for a sample MTP.(Smith, 2008) Table 29.Sample massive transfusion protocol (MTP) (Smith, 2008)

Hypothermia
Hypothermia is defined as a core temperature less than 36 °C.Hypothermia is usually caused by prolonged exposures to cold temperatures.Many trauma patients present to the operating room very cold secondary to prolonged exposure to the elements after the initial trauma.Mild hypothermia, about 1-2 °C below normal triples the incidence of morbid cardiac outcomes, triples the incidence of wound infections, directly impairs immune function, prolongs hospitalization by up to 20%, significantly increases surgical blood loss, and can lead to cold-induced platelet dysfunction.(Lovich-Sapola, 2010) Trauma patients may enter the operating room already cold, but even if they are normothermic, the patients' core temperatures usually decrease by 0.5-1.5 °C in the first 30 minutes after the induction of anesthesia secondary to the internal redistribution of heat.Mechanisms for heat loss include radiation loss, convection loss, conduction loss, and evaporative loss.(Lovich-Sapola, 2010)  -Sapola, 2010 andSmith, 2008) www.intechopen.com During the active re-warming of a patient, the following monitors are routine: continuous core temperature monitor and bladder catheterization to monitor the urine output and therefore the adequacy of the intravascular volume and organ perfusion.Arterial line for continuous blood pressure monitoring and frequent blood gas draws is also valuable.On occasion, a pulmonary artery catheter may be useful to follow the cardiac output (Lovich-Sapola, 2010)

Fat embolism syndrome
Fat embolism syndrome (FES) occurs when microembolism of fat and marrow from the patients long-bones result in clinically significant symptoms.Intra-operative transesophageal echocardiography (TEE) has shown that most patients undergoing longbone fracture manipulation experience this microembolization, but most patients do not have any clinical impact.Clinically significant FES occurs in about 3-10% of patients having a long-bone repair with the higher incidence if the patient has multiple long-bone fractures.
"The presentation of FES can be gradual, developing over 12 to 72 hours, or fulminate leading to acute respiratory distress and cardiac arrest."(Miller, 2009)  (Miller, 2009;Smith, 2008) Treatment for Fat Embolism Syndrome (FES)  Early recognition  Ventilation management: oxygen, higher PEEP, and possible long-term mechanical ventilatory support  Judicious fluid management Table 33.Treatment for FES (Miller, 2009)

Acute compartment syndrome
Acute compartment syndrome is defined as a "condition in which increased pressure within a limited space compromises the circulation and function of the tissues within that space."The most common fractures associated with compartment syndrome are the tibial shaft and forearm.The most common cause of compartment syndrome with orthopedic trauma patients is edema secondary to muscle injury and associated hematoma formation.(Miller, 2009) The diagnosis of acute compartment syndrome is primarily clinical.(Olsen, 2005) The earliest symptoms are often "pain out of proportion to the injury", pain with passive motion, and tense swelling of the affected area.(Miller, 2009;Smith, 2008) Decreased distal sensation and loss of proprioception are seen next, followed by complete anesthesia and muscle weakness.(Smith, 2008) The late-onset "classic"symptoms of pulselessness, pallor, paralysis, and paresthesia often do not present until irreversible loss of function has occurred.(Miller, 2009;Olsen, 2005;Smith, 2008)) The Surgeon and the Anesthesiologist must be careful because certain anesthetic techniques such as nerve blocks and epidural anesthesia can mask these symptoms and lead to a delay in diagnosis.This delay can be limb-threatening.(Olsen, 2005) These same symptoms can also be masked by an altered level of consciousness, deep sedation, or large doses of pain medication; therefore a high index for suspicion is required along with serial physical examinations so that the compartment syndrome is not missed.(Miller, 2009;Smith, 2008) The treatment for compartment syndrome is a fasciotomy of all involved compartments.To be effective, the fasciotomy must be performed as early as possible to prevent irreversible damage.(Miller, 2009) Conditions  (Miller, 2009;Olsen, 2005)

Post-operative pain management
Managing a patient's pain is always challenging, but it can be especially difficult in a polytrauma/multiple orthopedic injury patient.Pain management in these patients will require a multimodal approach.Inadequate analgesia can lead to complications with healing, immune function, and autonomic dysfunction.Prolonged untreated pain can lead to the development of a chronic pain state that can be very difficult to treat and may lead to lifelong problems.The goal of pain management in a trauma patient is to reduce the stress response, and provide the patient with pain relief while maintaining cardiovascular stability and tissue homeostasis.(Smith, 2008) The initial pain management after an orthopedic surgery case usually begins in the recovery room.The administration of rapidly acting intravenous agents in small doses at frequent intervals under continuous monitoring should be continued until adequate pain relief is attained.The total dose of medication required to relieve the patient's pain can then be used to determine the patient's basal requirements before starting a long-acting medication or patient-controlled analgesia (PCA).(Miller, 2009) Post-operative physical therapy after an orthopedic injury can have a significant impact on the pain medication requirements.It is important to consider the physical therapy schedule and plan the pain medication dosing appropriately.The goal of the dosing is to allow for enough pain relief to successfully perform the physical therapy but not so much that they are too sedated to participate.Physical therapy and activity after an orthopedic trauma is very important because it lowers the risk of pulmonary embolism, venous thrombosus, and decubitus ulcers.While physical therapy is more painful in the short term, the sooner the patient is mobilized, the lower the analgesic doses will be in the long term.(Miller, 2009) Neuropathic pain occurs when there is direct injury to a major sensory nerve.This type of injury is common after spinal cord trauma, traumatic amputations, and major crush injuries.
Neuropathic pain presents with a burning sensation, intermittent electrical shocks, and dysthesia in the affected dermatomal distribution.Neuropathic pain often responds poorly to narcotic analgesics used for somatic pain.The first line of treatment should be with gabapentin, 200 mg three times per day, with daily titration up to a maximum of 2-3 g/day.Persistent neuropathic pain may require selective regional anesthesia to "break the cycle" of spinal cord receptor recruitment.(Miller, 2009)

Pharmacologic measures
Acetaminophen is an analgesic/ antipyretic drug.It is popular because it is relatively safe compared with other anti-inflammatory medications.Acetaminophen is an important adjuvant to opioid analgesia because it decreases the total amount of opioid required and therefore decreases the adverse effects of excess opioids.The ceiling effect of oral acetaminophen is 1g/dose.(Smith, 2008) Nonsteroidal anti-inflammatory drugs (NSAIDs) are powerful COX inhibitors and the first line treatment for many pain conditions.NSAIDs are effective for moderate to severe pain.The use of NSAIDs is often limited by their side effect profile: gastric ulcers, renal and platelet dysfunction, and decreased bone fusion and healing which is particularly troublesome in orthopedic trauma patients.(Smith, 2008) Opioids are the cornerstone of acute pain management.The most commonly used types of opioids include: morphine, meperidine, codeine, fentanyl, hydromorphone, oxycodone, methadone, and buprenorphine.Opioids significantly decrease pain score ratings in trauma patients.Carefully titrated opioids are used as the most common treatment method in trauma cases.The opioids are usually given by a fixed dosing schedule or PCA technique.
Opioids can be administered by several routes (oral, intravenous, subcutaneous, intramuscular, intrathecal, epidural, transmucosal, transdermal, inhaled, intra-articular, and local injection into the wound) thus making them very versatile in clinical applications.Side effects of opioids include nausea, vomiting, constipation, sedation, altered sensorium, and respiratory depression.(Smith, 2008) Ketamine, a phencyclidine derivative, is a noncompetitive inhibitor at the NMDA receptor.Ketamine is unique in that it produces a dissociative state that causes amnesia and an intense analgesia, while maintaining the vital brain stem functions and hemodynamic stability.It provides profound amnesia and analgesia.Ketamine has been shown to decrease opioid requirements.Ketamine is a very useful drug for frequent dressing changes, treating burn patients, and minor trauma procedures.The drawbacks of ketamine include resulting excessive secretions, agitation on recovery, hallucinations, and increase in intracranial and intraocular pressure.The hallucinations can be decreased by giving a benzodiazepine.Ketamine should be avoided in any patient with an associated head trauma.(Smith, 2008) Tricyclic antidepressants (TCAs) are useful in the treatment of neuropathic pain conditions.TCAs are especially helpful in trauma patients because they can reduce pain, facilitate sleep, and alleviate depression.TCAs have a delayed onset of action; the patient must be educated that it may take days to see results.Recommended TCAs include amitriptyline, nortriptyline, imiprimine, and desipramine.Side effects can include: prolonged QT interval, arrhythmia, and paralytic ileus.(Smith, 2008) Gabapentin and pregabalin are anticonvulsants used to treat neuropathic, postsurgical, and posttraumatic pain.These medications can only be given in the oral form, so they can not be started until the patient is tolerating food.Side effects may include sedation, dizziness, confusion, and headache.(Smith, 2008) Multimodal analgesia is the key to the treatment of pain in a poly-trauma patient.The goal is an optimal balance of multiple medications.In addition to pharmacologic methods, nonpharmacologic approaches such as psychologic support, counseling, hypnosis, relaxation techniques, biofeedback, and acupuncture should be considered.(Smith, 2008) 8.2 Regional anesthesia Regional analgesia from an epidural or continuous catheter should be considered in any orthopedic trauma patient if possible secondary to the resultant sparing of narcotics, high level of patient satisfaction, improved pulmonary function (with associated thoracoabdominal injury), and facilitated early mobilization.(Miller, 2009) Localized and regional pain can be treated with local, regional, or neuraxial analgesia.Regional blocks provide selective pain relief with fewer hemodynamic side effects than neuraxial blocks.Regional anesthesia can decrease the need for opioids and therefore result in decreased nausea, vomiting, and sedation.Regional anesthesia can also be used for surgical anesthesia as well as post-operative pain management.(Smith, 2008) Prior to any block, the Anesthesiologist must first evaluate the patient.A review of the patient's medical history including an evaluation for preexisting neurologic injuries, medication history, capability to give informed consent, ability to cooperate for the procedure, availability of landmarks, ability to properly position the patient for the procedure, laboratory values (coagulation studies and platelet count), and finally the approval of the Surgeon to perform the block.A block has the potential to delay the diagnosis of a compartment syndrome and potentially worsen existing nerve damage, and therefore may not be safe in certain patients.(Smith, 2008) Ultrasound guidance is recommended for the placement of any regional block, but especially in trauma patients, secondary to the maximal benefit of patient safety and comfort.The peripheral nerve stimulation technique can be painful and should be avoided.(Smith, 2008) 8  (Miller, 2009;Smith, 2008) www.intechopen.com(Miller, 2009;Smith, 2008) 8.2.3 Intravenous (IV) regional anesthesia (Bier's block) IV regional anesthesia is a simple, reliable, cost effective block that is good for short operative procedure on an extremity.Lidocaine is the recommended drug for this block, secondary to it being less cardiotoxic than bupivacaine.IV regional anesthesia requires exsanguination of the limb with a tight bandage, which may be very uncomfortable to an injured limb.Early deflation of the cuff used to keep the local anesthesia in the affected extremity can result in local anesthetic toxicity.(Smith, 2008)

Epidural anesthesia
Epidural anesthesia has been shown to provide superior dynamic analgesia for the treatment of post-operative hip fracture pain during rehabilitation.The patients are significantly less restricted by their pain.However, studies have shown that this decrease in pain does not significantly translate into enhanced rehabilitation.(Foss, 2005) Again, patients undergoing a hip fracture surgery have the highest risk of death from a pulmonary embolism.A spinal anesthetic is recommended for the actual surgery, but an epidural is rarely indicated for post-operative pain management secondary to the aggressive postoperative anticoagulation that will be initiated.(Miller, 2009)

Conclusion
Orthopedic trauma requires a coordinated approach between the Surgeon and the Anesthesiologist.Orthopedic cases can often be some of the most complex for the Anesthesiologist secondary to the associated co-morbidities of the patient and the potential for multiple simultaneous injuries.
Every patient requires a preoperative evaluation that is complete as possible in the time allowed.Airway management may be difficult secondary to the potential for associated cervical spine injuries, and the proper preparation and precautions should be taken.Every patient requires the standard ASA monitors for the procedure, whether the orthopedic procedure is performed in the operating room, emergency room, or angiography suite.
The anesthetic technique should be chosen after careful evaluation of the risks and benefits of regional versus general anesthesia.It is important to remember that often a combination of both will yield the best results.
The Anesthesiologist and the Orthopedic surgeon should be prepared for intra-operative complications including hypotension, blood loss, hypothermia, fat embolism, and compartment syndrome.Vigilance for these potential complications will lead to early diagnosis and treatment, and therefore a potentially improved outcome.
Finally, post-operative pain management also requires a multi-modal approach for the best results.Consider consulting the hospital's Acute Pain Management team for assistance.Untreated pain can lead to chronic pain syndromes and delayed rehabilitation in the orthopedic injury patient.

Table 4 .
Respiratory system considerations in morbid obesity

Table 10 .
Timing for Rapid Sequence Induction and Intubation (RSI).

Table 12
(Lovich-Sapola, 2010)ck is immobilized, multiple different techniques can be used to improve the success of intubation, including the McCoy blade, Wu/ Bullard scope, Glidescope, and flexible fiberoptic scope.(Lovich-Sapola,2010)Theuse of a Glidescope with in-line stabilization has been shown to provide better glottic visualization, but does not significantly decrease the movement of the cervical spine when compared to direct laryngoscopy.(Robitaille,2008)Ifthecervical collar was removed during intubation, it should be replaced immediately after the intubation is confirmed.(Lovich-Sapola,2010) (Lovich-Sapola, 2010)nitoringEvery anesthetSmith, 2008) the location requires standard ASA monitors.These include a person qualified to monitor, evaluate, and care for the patient present in the room at all times and a way to monitor the patient's oxygenation, ventilation, circulation, and body temperature.(Lovich-Sapola,2010).Standard ASA Monitors (Lovich-Sapola, 2010;Smith, 2008)www.intechopen.com

Table 13 .
(Lovich-Sapola, 2010)lacement of an arterial line.(Lovich-Sapola,2010)Invasivearterialbloodpressuremonitoring requires the placement of a catheter into an artery, usually the radial, brachial, or femoral artery.The placement of an arterial line is not without risk.The complications of an arterial line include distal ischemia secondary to thrombosis, proximal emboli, or prolonged shock, pseudoaneurysm, arteriovenous fistula, hemorrhage, hematoma, infection, skin necrosis, peripheral neuropathy, misinterpretation of data, and cerebral air embolism secondary to retrograde flushing of the catheter.(Lovich-Thepatient'scoretemperature should be monitored for any case requiring anesthesia for longer than 20-30 minutes.Every effort should be made to maintain normothermia throughout the case.(Lovch-Sapola,2010)Maintainingeuthermia can be very challenging in a trauma case secondary to the large volumes of fluid resuscitation and multiple areas of patient exposure.(Smith,2008)Thenormalbody temperature is 36.7 °C to 37.0 °C ±0.2 ° C to 0.4 ° C. Continuous monitoring is recommended, but 15 minute intervals is acceptable.Core temperature sites for measurement include the pulmonary artery, distal esophagus, tympanic membrane, and nasopharynx.Intermediate sites include the mouth, axilla, bladder, and rectum.(Lovich-Sapola,2010) www.intechopen.com

for Central Venous Access and Central Venous Monitoring
TEE has become the preferred method for assessing hemodynamics in trauma patients.TEE is an excellent monitor of ventricular performance and volume.TEE in a trauma patient can be used to asses left and right ventricular function, wall motion abnormalities, valvular disease, pericardial effusion, cardiac tamponade, aortic injury, diastolic function, and pulmonary embolism.TEE can be used to estimate the pulmonary artery systolic pressure, left ventricular end-diastolic pressure, and CVP.In the 2010 practice guidelines update for perioperative TEE, the consultants and ASA members:Agree that TEE should be used for noncardiac surgical patients when the patient has known or suspected cardiovascular pathology that might result in hemodynamic, pulmonary, or neurologic compromise.Stronglyagree that TEE should be used during unexplained persistent hypotension.

Table 20 .
Advantages and disadvantages of general anesthesia in an orthopedic trauma patient

Table 22 .
(Smith, 2008)1)anesthetic agents include propofol, etomidate, ketamine, thiopental, and midazolam.Volatile anesthetics include isoflurane, sevoflurane, desflurane, and nitrous oxide.Nitrous oxide is generally avoided in trauma due to its ability to diffuse into air containing cavities, especially in patients with pneumothorax, intestinal obstruction, intracranial air, and air embolism(Bassett, 2011).Most anesthetic agents have direct cardiovascular depressant effects and inhibit compensatory hemodynamic reflexes such as central catecholamine output and baroreceptor reflexes.Baroreceptor depression is typically greater for the volatile agents compared to IV agents.In hypotensive patients, etomidate or ketamine are the preferred induction Etomidate offers greater cardiovascular stability compared to propofol or thiopental.Heart rate, cardiac output, and cardiac contractility usually remain unchanged.Ketamine typically increases blood pressure, heart rate, and cardiac output, making it favorable for hypovolemic patients.Isoflurane, sevoflurane, and desflurane all decrease blood pressure through reductions in systemic vascular resistance and depression of myocardial contractility.Isoflurane and desflurane both cause an increased heart rate to compensate for the fall in blood pressure.Sevoflurane is nonpungent which makes it a good choice for inhalational induction.Emergence delirium after sevoflurane occurs in pediatric patients.Desflurane is associated with fast wakeup times due to its low blood gas solubility.(Bassett,2011)Sideeffects of succinylcholine(Smith, 2008)Hypotension produced by anesthetic agents can contribute to the development of cerebral ischemia.Thiopental, propofol, midazolam, and etomidate produce dose dependent reductions in cerebral spinal fluid formation, cerebrovascular constriction causing decreased cerebral blood flow, and decreased cerebral metabolic requirement for oxygen (CMRO 2 ).

Table 25 .
Orthopedic injuries requiring urgent surgical treatment

Table 28 .
Types of shock

Table 32 .
Clinical manifestation for FES

Table 34 .
Conditions that can result in acute compartment syndrome

Table 38 .
Upper limb blocks

Table 39 .
Lower limb blocks

Table 40 .
(Smith, 2008)sk/ benefit analysis is necessary in all patients: special concern if they are coagulopathic, have a low platelet count, are on blood thinners  Evolution of neurologic deficits from an expanding hematoma can take 4 hours to 3 days to manifest itself  Lack of treatment of a hematoma can lead to axon loss and sensory/ motor deficit  Consider pre-existing trauma or vascular injury before the placement of any block Diaphragm Weakness  The phrenic nerve lies close to the interscalene groove (easily blocked by the interscalene approach to the brachial plexus)  Unilateral diaphragm weakness is not usually significant in healthy patients, but it can be devastating in patients with chest trauma, poor pulmonary status, or a pneumothorax Pneumothorax  Serious complication of the supraclavicular brachial plexus block and intercostal nerve block  Rare after the interscalene and infraclavicular approach Symptoms can be delayed and present as long as 6-12 hours after the procedure.Complications of regional anesthesia(Smith, 2008)