Jennifer McNulty, MD

• Associate Clinical Professor
• Department of Obstetrics and Gynecology
• Division of Maternal Fetal Medicine
• University of California at Irvine
• Staff Perinatologist
• Long Beach Memorial Women? Hospital
• Long Beach, California

Infected cysts may be obscured by surrounding pneumonia allergy symptoms face numbness cheap seroflo 250mcg visa, or they may be difficult to differentiate from an empyema allergy medicine erowid order seroflo with visa. Conservative surgical excision of bronchogenic cysts is generally recommended allergy haven cheap 250 mcg seroflo with mastercard, regardless of whether a bronchial communication is evident allergy warning label order discount seroflo online. Pulmonary hydatid cysts are watery allergy symptoms loss of taste best buy for seroflo, parasitic cysts containing larvae of the dog tapeworm Echinococcus granulosus allergy treatment xanthelasma buy 250mcg seroflo otc. Hydatid cysts may grow in diameter by as much as 5 cm per year and become medically problematic in several ways. Spontaneous or traumatic rupture may occur, sending fluid, parasites, or laminated debris into adjacent tissue, bronchus, pleura, or the circulation. Drainage into the bronchi may cause dramatic expulsion of fluid with respiratory distress or asphyxiation, depending on the amount of fluid involved. Rupture into the pleural space may result in a large hydropneumothorax, severe dyspnea, shock, suffocation, or anaphylaxis. Small, intact peripheral cysts are often easily enucleated without loss of lung parenchyma. Indications and contraindications to lung transplantation are summarized in Box 66-12. Approximately 1500 lung transplants are performed annually worldwide; the number is limited by the supply of donor organs. Pulmonary fibrosis: idiopathic, associated with connective tissues disorders, other 4. Primary pulmonary hypertension There are also several other, rarer indications such as primary bronchoalveloar lung cancer, lymphangioleiomyomatosis, and so on. An overall 5-year survival rate of 50% is the benchmark but depends on recipient age and diagnosis. Chest radiograph of a patient with cystic fibrosis for bilateral lung transplantation. Monitoring includes invasive arterial and pulmonary catheters and transesophageal echocardiography in most centers. Despite advances in lung preservation techniques, it is optimal to limit the donor lung ischemic period to 4 hours. The intraoperative anesthetic complications depend, in large part, on the underlying lung disease. Most transplant recipients can be managed according to routine anesthetic practice including optimal perioperative respiratory care, antibiotic prophylaxis, and maintenance of immune suppression. Most adults with bronchial anastomoses have no problem with endotracheal intubation. Single-lung transplant recipients with native lung emphysema are a specific concern. They have a marked imbalance in pulmonary compliance, with the native lung highly compliant and the donor lung of normal or reduced (if there is rejection) compliance. However, the major proportion of the pulmonary blood flow is usually to the allograft. With standard methods of positive-pressure ventilation, dynamic hyperinflation of the emphysematous lung with hemodynamic instability and problems with gas exchange may develop in these patients. Immediate postoperative improvements in symptoms and pulmonary function are common, and many patients are able to discontinue or reduce home oxygen therapy. Despite the encouraging changes in early postoperative pulmonary function, the improvement in respiratory function as a result of this surgery is transient. The commonest causes are carcinoma, bronchiectasis, and trauma (blunt, penetrating, or secondary to a pulmonary artery catheter). Management requires four sequential steps: lung isolation, resuscitation, diagnosis, and definitive treatment. The anesthesiologist is often called to deal with these cases outside of the operating room. Fiberoptic bronchoscopy is usually not helpful to position endobronchial tubes or blockers in the presence of torrential pulmonary hemorrhage, and lung isolation must be guided by clinical signs (primarily auscultation). Even if a left-sided tube enters the right mainstem bronchus, only the right upper lobe will be obstructed. The surgery is more effective in patients with heterogeneous lung disease, where the most severely affected areas (often apical) can be resected, than in patients with homogenous types of emphysema. Chapter 66: Anesthesia for Thoracic Surgery 1995 have been achieved, diagnosis and definitive therapy of massive hemoptysis are now most commonly performed by coiling of the pulmonary artery false aneurysm in interventional radiology. When hemoptysis does occur in this situation, there are several management options available. The use of a pulmonary artery vent may be required to decrease the pulmonary blood flow sufficiently to define the bleeding site (usually the right lower lobe). Conservative management with lung isolation, to avoid lung resection, is optimal therapy if possible. This complication seems to be occurring less than previously, possibly related to stricter indications for the use of pulmonary artery catheters and more appropriate management of the catheters with less reliance on wedge measurements. Posttracheostomy Hemorrhage Hemorrhage in the immediate postoperative period after a tracheostomy is usually from local vessels in the incision such as the anterior jugular or inferior thyroid veins. Massive hemorrhage 1 to 6 weeks postoperatively is most commonly caused by tracheoinnominate artery fistula. The management protocol for tracheoinnominate artery fistula is outlined in Box 66-14. Flow diagram of management of massive hemoptysis during weaning from cardiopulmonary bypass. Patients present with severe dyspnea on exertion and signs of right-sided heart failure. Support of systemic vascular resistance with noradrenaline or phenylephrine is usually required. Postoperatively, the patients are kept sedated, intubated, and ventilated for at least 24 hours to decrease the risk of reperfusion pulmonary edema. Noradrenalin or vasopressin infusions may be used to elevate the systemic vascular resistance and decrease cardiac output to decrease pulmonary blood flow. It is the most effective treatment modality for symptomatic pulmonary alveolar proteinosis. This lung disease results from accumulation in the alveoli of a lipoprotein material similar to surfactant. General anesthesia is induced and maintained with intravenous infusions as for lung transplantation. Because of transmitted hydrostatic pressure from the lavage lung to the pulmonary circulation, oxygenation increases during the filling phase and decreases during the emptying phase in synchrony with changes in the pulmonary blood flow distribution. Usually 10 to 15 L is instilled and more than 90% is recovered, leaving a deficit of less than 10%. A dose of furosemide (10 mg) is administered to increase diuresis of absorbed saline. If there is a persistent large alveolar-arterial oxygen gradient, the procedure is terminated at this stage and the patient will undergo lavage of the other lung at a later date. Chapter 66: Anesthesia for Thoracic Surgery 1997 unit for 24 hours is part of the routine procedure. Some patients require lavage every few months, whereas others remain in remission for years. Tumors of the mediastinum include thymoma, teratoma, lymphoma, cystic hygroma, bronchogenic cyst, and thyroid tumors. Mediastinal masses may cause obstruction of major airways, main pulmonary arteries, atria, and the superior vena cava. During induction of general anesthesia in patients with an anterior or superior mediastinal mass, airway obstruction is the most common and feared complication. It is important to note that the point of tracheobronchial compression usually occurs distal to an endotracheal tube. A history of supine dyspnea or cough should alert the clinician to the possibility of airway obstruction on induction of anesthesia. These deaths may be the result of the more compressible cartilaginous structure of the airway in children or because of the difficulty in obtaining a history of positional symptoms in children. First, reduced lung volume occurs during general anesthesia and tracheobronchial diameters decrease according to lung volume. Second, bronchial smooth muscle relaxes during general anesthesia, allowing greater compressibility of large airways. Finally, third, paralysis eliminates the caudal movement of the diaphragm seen during spontaneous ventilation. This eliminates the normal transpleural pressure gradient that dilates the airways during inspiration and minimizes the effects of extrinsic intrathoracic airway compression. Patients with "uncertain" airways should have diagnostic procedures performed under local or regional anesthesia whenever possible. Patients with "uncertain" airways requiring general anesthesia need a step-by-step induction of anesthesia with continuous monitoring of gas exchange and hemodynamics. If muscle relaxants are required, ventilation should first be gradually taken over manually to ensure that positive-pressure ventilation is possible, and only then can a short-acting muscle relaxant be administered (Box 66-17). The salient points in managing a patient with an anterior or superior mediastinal mass include254: 1. In virtually all children and adults with a mediastinal mass, diagnostic procedures and imaging can be performed, if necessary, without subjecting the patient to the risks of general anesthesia. An extrathoracic source of tissue for diagnostic biopsy (pleural effusion or extrathoracic lymph node) should be sought as an initial measure in every patient. Regardless of the proposed diagnostic or therapeutic procedure, the flat, supine position is never mandatory. In the high-risk child (Box 66-18) without extrathoracic lymphadenopathy or a pleural effusion, prebiopsy steroid therapy is justifiable. An alternative to preoperative steroids in the cooperative high-risk patient includes irradiating the tumor while leaving a small area covered with lead for subsequent biopsy. With improved awareness of the risk of acute intraoperative airway obstruction in these patients, life-threatening events are now less likely to occur in the operating room. In children, these events now tend to occur preoperatively if the patient is forced to assume a supine position for imaging. In adults, acute airway obstruction is now more likely to occur postoperatively in the recovery room. Development of airway or vascular compression requires that the patient be awakened as rapidly as possible and then other options for the procedure be explored. Intraoperative life-threatening airway compression usually has responded to one of two therapies: either repositioning of the patient (it must be determined before induction if there is a position that causes less compression and fewer symptoms) or rigid bronchoscopy and ventilation distal to the obstruction (this means that an experienced bronchoscopist and equipment must always be immediately available in the operating room for these cases). The rigid bronchoscope, even if passed into only one mainstem bronchus, can be used for oxygenation during resuscitation (see Rigid Bronchoscopy, discussed earlier). Thymectomy is frequently performed to induce clinical remission, even in the absence of a thymoma. The effects of muscle relaxants are modified by this disease; myasthenic patients are resistant to succinylcholine and are extremely sensitive to nondepolarizing blockers. In the absence of an identifiable tumor, minimally invasive techniques are commonly used. Induction of anesthesia with propofol, remifentanil, and topical anesthesia of the airway facilitates intubation without the use of muscle relaxants. Alternatively, inhalational induction with a halogenated agent such as sevoflurane may be performed. Most patients take pyridostigmine, an oral anticholinesterase, and many patients take immunosuppressive medication. A scoring system was devised for prediction of the need for prolonged mechanical ventilation after thymectomy via sternotomy. The relevance of this score has diminished with better preoperative preparation and minimally invasive surgery. In optimized patients, mean hospital length of stay can be reduced to 1 day after minimally invasive, and 3 days after transsternal thymectomy. The remission from myasthenia gravis after thymectomy occurs slowly over a period of months to years. Respiratory Failure Respiratory failure is a leading cause of postoperative morbidity and mortality in patients undergoing major lung resection. Acute respiratory failure after lung resection is defined as the acute onset of hypoxemia (PaO2 <60 mm Hg) or hypercapnia (Paco2 >45 mm Hg), or the use of postoperative mechanical ventilation for more than 24 hours or reintubation for controlled ventilation after extubation. Patients with decreased respiratory function preoperatively are at increased risk of postoperative respiratory complications. In addition, age, the presence of coronary artery disease, and the extent of lung resection play major roles in predicting postoperative morbidity and mortality. Crossover contamination, because of the failure of lung isolation intraoperatively during lung resection in patients with contaminated secretions, can result in contralateral pneumonia and postoperative respiratory failure. Decreased pulmonary complications in high-risk patients are associated with the use of thoracic epidural analgesia during the perioperative period. For an uncomplicated lung resection, early extubation is desirable to avoid potential complications that can arise as a result of prolonged intubation and mechanical ventilation. Current therapy to treat acute respiratory failure is supportive therapy attempting to provide better oxygenation, treat infection, and provide vital organ support without further damaging the lungs. Cardiac Herniation Acute cardiac herniation is an infrequent but well described complication of pneumonectomy, where the pericardium is incompletely closed or the closure breaks down. Cardiac herniation may also occur after a lobar resection with pericardial opening, or in other chest tumor resections involving the pericardium or in trauma.

If significant hypotension results allergy medicine 6 symptoms generic 250mcg seroflo with visa, gradual release of the aortic clamp and reapplication or digital compression are important measures in maintaining hemodynamic stability during unclamping allergy forecast fairfield ct cheap seroflo online american express. AoX allergy symptoms lilies order seroflo once a day, Aortic cross-clamping; Cven allergy testing reading results order seroflo amex, venous capacitance; R art allergy shots zyrtec order seroflo 250 mcg visa, arterial resistance; Rpv allergy forecast clarksville tn discount 250 mcg seroflo fast delivery, pulmonary vascular resistance. Continuous monitoring of ventricular function is commonly obtained with a single short-axis view at the level of the midpapillary muscle. Using this same view, visualization of the left ventricle at end-diastole allows rapid assessment of ventricular filling (preload). Ejection fraction area can be calculated by use of the left ventricular end-diastolic and end-systolic area. In patients undergoing abdominal aortic reconstruction, echocardiographic short-axis left ventricular end-diastolic area, end-systolic area, and ejection fraction area correlate closely with changes in corresponding left ventricular volume and ejection fraction obtained by radionuclide angiography. Patients requiring supraceliac aortic cross-clamping have significant increases in end-diastolic area and significant decreases in ejection fraction on echocardiography that are not completely normalized with vasodilators and frequently are not detected by pulmonary artery catheter monitoring. The short-axis view at the level of the midpapillary muscles allows assessment of all three major coronary distributions. The natural history of echocardiographic segmental wall motion abnormalities was studied in 156 patients undergoing noncardiac surgery who were at risk for cardiac morbidity. The 24 patients undergoing aortic surgery had the highest incidence of new segmental wall motion abnormalities (38%). Thus, available data are insufficient to define the sensitivity and specificity of segmental wall motion abnormalities as a marker for myocardial ischemia or as a predictor of perioperative ischemic outcomes. The optimal intraoperative monitoring techniques for patients undergoing abdominal aortic reconstruction have not been established. The clinical usefulness of any monitoring technique ultimately depends on patient selection, accurate interpretation of data, and appropriate therapeutic intervention. Another randomized study found that the combined use of the two techniques during aortic surgery was cost neutral in comparison to standard allogeneic transfusion. Anesthetic Drugs and Techniques A variety of anesthetic techniques, including general anesthesia, regional (epidural) anesthesia, and combined techniques, have been used successfully for abdominal aortic reconstruction. Combined techniques most commonly use a lumbar or low thoracic epidural catheter in addition to a "light" general anesthetic. Local anesthetics, opioids, or, more commonly, a combination of the two may be administered by bolus or continuous epidural infusion. Maintenance of vital organ perfusion and function by the provision of stable perioperative hemodynamics is more important to overall outcome than is the choice of anesthetic drug or technique. Given the frequent incidence of cardiac morbidity and mortality in patients undergoing aortic reconstruction, factors that influence ventricular work and myocardial perfusion are of prime importance. Induction of general anesthesia should ensure that stable hemodynamics are maintained during loss of consciousness, laryngoscopy and endotracheal intubation, and the immediate postinduction period. The addition of a short-acting, potent opioid such as fentanyl 3 to 5 g/kg) usually provides stable hemodynamics during and after induction of anesthesia. Volatile anesthetics may be administered in low concentrations before endotracheal intubation during assisted ventilation as an adjunct to blunt the hyperdynamic response to laryngoscopy and endotracheal intubation. Esmolol 10 to 25 mg, sodium nitroprusside 5 to 25 g, nitroglycerin 50 to 100 g, and phenylephrine 50 to 100 g should be available for bolus administration during induction if needed to maintain appropriate hemodynamics. Maintenance of anesthesia may be accomplished with a combination of a potent opioid (fentanyl or sufentanil) and an inhaled anesthetic (sevoflurane, desflurane, or isoflurane). Patients with severe left ventricular dysfunction may benefit from a pure opioid technique, but a balanced anesthetic technique allows the clinician to take advantage of the most desirable characteristics of potent opioids and inhaled volatile anesthetics while minimizing their undesirable side effects. Nitrous oxide can be used to supplement either an opioid or an inhaled anesthetic. Approximately 50% of the opioid dose is administered during induction of anesthesia and before skin incision. When epidural local anesthetics are used, this author uses the same technique and reduces the fentanyl dose to 6 to 8 g/kg. Various regional anesthetic and analgesic techniques have been used effectively during and after aortic reconstruction. Suprarenal aneurysms and other more complex aortic reconstructions often demand even greater allogeneic blood availability. Over the last 2 decades, concerns regarding the safety, availability, and acceptability of allogeneic blood have led to greater use of autologous blood procurement (see also Chapters 61 and 63). Preoperative autologous donation, intraoperative cell salvage, and acute normovolemic hemodilution have all been used during aortic surgery to reduce or eliminate exposure to allogeneic blood and the associated risks for transfusionrelated complications. Intraoperative cell salvage is the most widely used technique and in some centers is considered routine. The routine use of cell salvage during aortic surgery may not be cost-effective ($250 to $350 per case), and thus it may best be reserved for a select group of patients with an expected large blood loss. The equivalent of at least 2 units of washed blood must be recovered for this technique to be cost-effective. A cost-effective option is to use the cell salvage reservoir for blood collection and activate the full salvage process only if large blood loss occurs. Acute normovolemic hemodilution is often used in conjunction with intraoperative cell salvage during aortic surgery. Two randomized studies reported that the combined use of hemodilution and cell salvage reduced the allogeneic blood requirement in patients undergoing aortic surgery. The benefits of combined general and epidural anesthesia intraoperatively, with or without epidural analgesia continued into the postoperative period, remain controversial. In a randomized trial using epidural morphine in patients undergoing aortic surgery, Breslow and associates79 found attenuation of the adrenergic response and a less frequent incidence of hypertension in the postoperative period. A large randomized trial reported no reduction in nonsurgical complications with the use of intrathecal opioid. Four randomized trials, with nearly 450 combined patients undergoing aortic reconstruction, failed to demonstrate a reduction in the incidence of perioperative,40,81 intraoperative,82 or postoperative77 myocardial ischemia when epidural techniques were used. Additionally, randomized trials have not demonstrated a reduction in the incidence of cardiovascular, pulmonary, or renal complications after aortic surgery with the use of epidural techniques. Length of hospital stay may therefore be considered the outcome variable most directly proportional to an integrated final negative effect of all significant perioperative morbidity (excluding in-hospital death) and the variable most likely to be altered by the anesthetic or analgesic technique. Randomized trials have not demonstrated any reduction in length of hospital stay after aortic surgery with the use of regional techniques. The study rigorously protocolized perioperative management, standardized postoperative surgical care, and optimized postoperative pain management. This design allows the inclusion of all four possible combinations on intraoperative anesthesia and postoperative analgesia and the ability to separate the influences of time period and technique. Data analysis by treatment group, intraoperative treatment, postoperative treatment, and any epidural activation, as well as simultaneous consideration of both intraoperative and postoperative treatments in the same model (factorial analysis), is possible and allows improvement in outcome to be attributed to the intraoperative anesthesia, postoperative analgesia, the combination of the two, or to unrelated factors. The overall incidence of postoperative complications in the trial was low and not different based on anesthetic or analgesic technique. Postoperative pain was well controlled overall, with similar pain scores in both analgesic treatment groups. The use of epidural local anesthetics in combination with general anesthesia during aortic reconstruction poses several problems, including hypotension at the time of aortic unclamping and the need for increased intravascular fluid and vasopressor requirements. Supraceliac aortic cross-clamping may significantly exaggerate these disadvantages, and, as a result, some clinicians avoid epidural local anesthetics for such procedures. Epidural opioids without local anesthetics can be used for procedures requiring supraceliac aortic cross-clamping. Epidural local anesthetic can be given later, after aortic unclamping, when hemodynamics and intravascular volume have stabilized. For low thoracic or high lumbar epidural catheters, the initial bolus should be limited to 6 to 8 mL of local anesthetic. Additional local anesthetic is administered by continuous infusion at 4 to 6 mL/hr with adjustments based on hemodynamics and inhaled anesthetic requirements during surgery. Although elective aortic reconstruction via the retroperitoneal approach using straight epidural anesthesia (no general anesthetic) has been reported, this technique is not recommended for routine use. Emergence from anesthesia should be conducted after restoration of circulation and establishment of adequate organ perfusion. Early extubation of the trachea is not generally attempted in patients with supraceliac aortic cross-clamp times longer than 30 minutes, patients with poor baseline pulmonary function, or patients requiring large volumes of blood or crystalloid during surgery. At the start of skin closure, inhaled anesthetics are discontinued, N2O is increased to 70%, and any residual neuromuscular blockade is reversed. I routinely insert a large nasal airway after induction of anesthesia, but before systemic heparinization in all patients for whom extubation is planned in the operating room. Hypertension and tachycardia are aggressively controlled during emergence by the use of short-acting drugs such as esmolol, nitroglycerin, and sodium nitroprusside. In these cases, mild sedation with a benzodiazepine such as midazolam is appropriate. Surgical repair is required for a spectrum of disease, including degenerative aneurysm, acute and chronic dissection, intramural hematoma, mycotic aneurysm, pseudoaneurysm, penetrating aortic ulcer, coarctation, and traumatic aortic tear. These advances have led to significant reductions in operative mortality and perioperative complications. However, even in centers where numerous procedures are performed, morbidity and mortality are frequent, especially in patients with dissecting or ruptured aneurysms. Intraoperative management requires a team effort with intimate cooperation among surgeons, anesthesiologists, perfusionists, nurses, and electrophysiologic monitoring staff. Endovascular stent-graft repair of lesions that affect the descending thoracic and thoracoabdominal aorta is evolving rapidly. As discussed later, accumulating experience with stent-graft repair of thoracic aortic aneurysm, dissection, and traumatic tear has demonstrated this modality to be an effective alternative to open repair for select patients. Temperature Control Postoperative hypothermia is associated with many undesirable physiologic effects and may contribute to adverse outcomes (see also Chapter 54). If significant hypothermia occurs early in the procedure, normothermia is extremely difficult to achieve, and emergence and tracheal extubation may be delayed. During surgery, all fluids and blood products should be warmed before administration. The lower part of the body should not be warmed because doing so can increase injury to ischemic tissue distal to the cross-clamp by increasing metabolic demands. The Crawford classification of thoracoabdominal aortic aneurysms is defined by anatomic location and the extent of involvement. The increasing diameter is associated with increased wall tension, even when arterial pressure is constant (law of Laplace). The frequent incidence of associated systemic hypertension enhances aneurysm enlargement. Additional symptoms can be caused by compression of organs or structures adjacent to the aneurysm. Rupture of the thoracic and abdominal segments occurs with equal frequency and primarily in patients with aneurysms larger than 5 cm. Surgical repair is usually recommended when aneurysm diameter exceeds 6 cm, but earlier repair may be offered to patients with Marfan syndrome and those with a strong family history of an aortic aneurysm. In addition to cause, aneurysms of the thoracoabdominal aorta may be classified according to their anatomic location. In 1986, Crawford and colleagues,84 recognizing the correlation between aneurysm extent and clinical outcome, proposed a classification based on the extent of aortic involvement. Type I aneurysms involve all or most of the descending thoracic aorta and the upper abdominal aorta. Even with extracorporeal circulatory support, an obligatory period occurs when blood flow to these organs is interrupted because the origin of the blood flow is between the cross-clamps. For this reason, protective measures to prevent ischemic injury are important in reducing morbidity. Aortic dissection, with or without aneurysm formation, has likewise been classified according to the extent of aortic involvement. Type I aneurysms begin in the ascending aorta and extend throughout the entire aorta. These lesions are usually repaired via a two-stage approach, with the first procedure on the ascending aorta and aortic arch and the second procedure on the descending thoracic aorta. Another commonly used classification of aortic dissection is the Stanford classification. Type I has an intimal tear in the ascending aorta with dissection extending down the entire aorta. Aortic dissection is also classified by duration, with those less than 2 weeks classified as acute and those greater than 2 weeks classified as chronic. This classification has very significant mortality implications, with much higher mortality in the acute phase. Early surgical intervention may be required for a variety of reasons, including aneurysmal formation, impending rupture, organ or leg ischemia, and inadequate response to medical therapy. In approximately 20% to 40% of patients with chronic aortic dissection, significant aneurysmal dilatation of the descending thoracic or thoracoabdominal aorta will develop. Contemporary mortality rates reported from large institutions range from 5% to 14%. Gastrointestinal complications occur in approximately 7% of patients and are associated with a mortality approaching 40%. The incidence of postoperative pulmonary insufficiency approaches 50%, with 8% to 14% of patients requiring tracheostomy. As with all other vascular surgical procedures, cardiac complications are common and a leading cause of perioperative mortality. The evaluation and management of coexisting cardiac and pulmonary disease are discussed earlier in this chapter. Before the day of surgery, the anesthesiologist and vascular surgeon should discuss, at a minimum, extent of the aneurysm and technique of surgical repair, plans for distal aortic perfusion, monitoring for spinal cord ischemia, renal and spinal cord protection, hemodynamic monitoring, and ventilation strategy. I use a large cooler to store blood products on ice in the operating room so that they can be returned to the blood bank if not used.

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Meta-analysis revealed only nonsignificant trends toward reduced incidence of delayed cerebral ischemia and death allergy forecast st louis order discount seroflo on-line. Recently (January 2013) allergy forecast west palm beach purchase seroflo with visa, the phosphodiesterase inhibitor cilostazol allergy symptoms difficulty swallowing buy 250 mcg seroflo, administered orally post clipping allergy forecast colorado cheap seroflo 250 mcg overnight delivery, was reported to reduce vasospasm and delayed cerebral infarctions substantially allergy medicine long term side effects order seroflo 250 mcg on line. Although the results were promising allergy testing bakersfield ca effective seroflo 250mcg, verification of both safety and efficacy will probably be required before wide application. Antifibrinolytics have been administered in an attempt to reduce the incidence of rebleeding. Although they accomplish this end, long courses do so at the cost of an increased incidence of ischemic symptoms and hydrocephalus, with an overall adverse effect on outcome. However, early, brief courses of antifibrinolytics continued until the aneurysm is secured may have a net favorable effect on outcome. The severity of the dysfunction correlates best with the severity of the neurologic injury203 and is sometimes sufficient to require pressor support. Achievement of intraoperative brain relaxation to facilitate surgical access to the aneurysm. The prevention of paroxysmal hypertension is the only absolute requirement in patients undergoing aneurysm clipping. The routine use of induced hypotension has essentially vanished (see previous section Management of Arterial Blood Pressure). Nonetheless, the anesthesiologist should be prepared to reduce blood pressure immediately and precisely if called upon to do so. A carrier drip flows steadily such Monitoring An arterial line is invariably appropriate. A central venous catheter may be appropriate if peripheral access is inadequate (see also Chapter 49). This can be extremely difficult in a patient who is hypovolemic at the beginning of the bleeding episode. In addition, after clipping of the aneurysm, some surgeons will puncture the dome of the aneurysm to confirm adequate clip placement and may request transient elevation of the systolic pressure to 150 mm Hg. However, the practice has been questioned on the basis of the concern that it will aggravate ischemia (see the earlier section Management of Paco2). Having verified the patency of the drainage system, it is usual to leave it closed until the surgeon is opening the dura. In part, it is used to facilitate exposure and reduce retractor pressures, but there is evidence that it may have additional benefits. Reduction of interstitial tissue pressure around capillaries and/or an alteration of blood rheology have been proposed as contributors. Typically, mannitol is administered in a dose of 1 g/kg just before dural opening. Many surgeons limit inflow to an aneurysm during application of the permanent clip by placing a temporary clip proximally on the feeding vessel. With giant aneurysms in the vicinity of the carotid siphon, the inferior occlusion may be performed at the level of the internal carotid artery via a separate incision in the neck. A clinical survey by Samson and colleagues of the neurologic outcome after temporary occlusion in normothermic, normotensive adults revealed that occlusions of fewer than 14 minutes were invariably tolerated. The likelihood of an ischemic injury increased with longer occlusions and reached 100% with occlusions in excess of 31 minutes. We do not select anesthetic drugs on the basis of putative brain-protective effects. Specific anesthetic drugs have been promoted as brain protectants (see the discussion in Chapter 17). However, there have been no convincing laboratory demonstrations that propofol provides any greater tolerance to a standardized ischemic insult than does anesthesia with a volatile anesthetic. Attempts to demonstrate protection by etomidate in an animal model of focal ischemia actually demonstrated an adverse effect of etomidate. During subsequent temporary vessel occlusion, tissue pH decreased alarmingly in patients receiving etomidate and was unchanged with desflurane. With respect to the volatile anesthetics, attempts in the laboratory to confirm the once proclaimed protective efficacy of isoflurane have demonstrated that there are no differences among the various volatile anesthetics in terms of their influence on outcome after focal or global ischemia in the laboratory. The important anesthetic objectives are precise hemodynamic control and timely wake-up, and those two constraints should dictate the choice of the anesthetic regimen for the majority of aneurysm procedures. Among anesthetics, it is only the barbiturates for which additional protective efficacy has been demonstrated convincingly (see Chapter 17). Because of their potentially adverse effects on hemodynamics and wake-up, they are not ideal for routine use. As noted in the section Hypothermia, a prospective trial of mild hypothermia in patients undergoing aneurysm surgery revealed no improvement in neurologic outcome. The institutions that use the lower temperatures are those in which the team is willing to accept a delay in emergence from anesthesia to achieve sufficient rewarming to avoid the extreme hypertension that can occur when a patient is awakened at low body temperatures. However, the more commonly used skin surface frontal-mastoid derivation is probably sufficient to reveal a major ischemic event. If the necessity for a sustained period of occlusion seems likely, it may be appropriate to administer barbiturates (discussed earlier) to produce burst suppression. Intraoperative angiography is an increasingly common component of the management of intracranial aneurysms. Special Considerations for Specific Aneurysms the most common procedures are performed for aneurysms arising in or close to the circle of Willis. The vessels of origin may be the anterior communicating artery; the middle cerebral artery; the anterior cerebral artery; the ophthalmic artery; the tip of the basilar artery; the posterior communicating artery; and, less frequently, the posterior cerebral artery. These procedures are relatively similar for the anesthesiologist and typically require a supine position with the head turned slightly away from the operative side. Access to the origin of the ophthalmic artery, which is the first intradural branch of the carotid artery, is made difficult by the anterior clinoid process and the optic nerve. When the surgeon reaches the stage of seeking definitive access to the neck of the aneurysm, he or she will occlude first the carotid artery in the neck and then the intracranial portion of the carotid artery immediately proximal to the origin of the posterior communicating artery. The exposure may involve a combined middle and posterior fossa approach, with some attendant, although minor, risk of venous air embolism. Spontaneous ventilation may be appropriate for procedures involving surgical manipulation of the vertebral arteries, the vertebrobasilar junction, and the middle portion of the basilar artery. Apnea, gasping, or other sudden changes in ventilatory pattern during manipulation of the vasculature provide important, though somewhat nonspecific, warning of compromise of the vascular supply of the brainstem. Although this explanation superficially fits the clinical occurrence, experimental data are not entirely consistent with this mechanism. The management constraints are essentially the same as those relevant to aneurysm surgery, although the risk of intraoperative rupture is much less. With severe episodes of swelling, we have used (in addition to hypotension, which we use cautiously because of the associated ischemia risk) hypocapnia, hypothermia, and barbiturates. The anesthesiologist, in choosing the intubation technique, may encounter a number of conflicting constraints (Box 70-9). There is no correct technique, and the best approach is determined by the relative weight of these various factors along with the degree of urgency. Do not risk losing the airway or causing severe hypotension for the sake of preventing coughing on the tube or brief hypertension with intubation. Chapter 70: Anesthesia for Neurologic Surgery 2183 the Cervical Spine the possibility of causing or aggravating an injury to the cervical spine is a relevant concern. Nonetheless, although the literature contains contradictions, several published series have concluded that rapid-sequence induction does not convey significant risk of neurologic injury. An informal survey reported by Criswell and associates239 indicated that there have been more such events than one can infer from the published literature. It is the (probably minority) opinion of these authors that the possibility of devastating spinal cord injury exists, probably most so with injuries in the atlanto-occipital region, which are also difficult to identify radiologically, and that the anesthesiologist should identify circumstances in which time latitudes allow more detailed examination or radiologic evaluation. When there is any uncertainty regarding the airway or the cervical spine, direct laryngoscopy (with vigorous atlanto-occipital extension) should probably be avoided when the exigencies of the situation do not require an immediate rapid-sequence induction. When a hypnotic-relaxant sequence is used (and the exigencies of airway control will frequently demand it), the standard approach includes the use of cricoid pressure and in-line axial stabilization. In-line traction was once favored but has been supplanted by stabilization because of the perceived risk of over distraction and cord injury in the event of gross instability. There is no question that in-line stabilization, properly performed, makes laryngoscopy somewhat more difficult; however, it serves to decrease the amount of atlanto-occipital extension necessary to achieve visualization of the glottis. Some recommend leaving the back half of the cervical collar in place during laryngoscopy. One assistant maintains in-line axial stabilization with the occiput held firmly to the backboard; a second applies cricoid pressure. The posterior portion of the cervical collar remains in place to limit atlantoaxial extension. In the extensive experience of the Cowley Shock-Trauma Center in Baltimore, the cricothyrotomy/tracheostomy rate is 0. What should the anesthesiologist do with the patient whose cervical spine has not been cleared Despite the frequency with which an anesthesiologist may encounter patients still wearing their cervical collars because their necks have not yet been cleared, no special precautions appear warranted in the asymptomatic, alert patient. Craniotomies are most commonly performed for the evacuation of subdural, epidural, or intracerebral hematomas. The guiding principles have been discussed in the section Control of Intracranial Pressure and Brain Relaxation. In general, anesthetics that are known to be cerebral vasoconstrictors are preferable to those that have the potential to dilate the cerebral circulation. All of the intravenous anesthetics, except perhaps ketamine, cause some cerebral vasoconstriction and are reasonable choices, provided they are consistent with hemodynamic stability. All of the inhaled anesthetics (N2O and all of the volatile anesthetics) have some cerebral vasodilatory effect. For patients who are likely to remain tracheally intubated postoperatively, an anesthetic based primarily on a narcotic, such as fentanyl, and a muscle relaxant usually serves well. Any muscle relaxant is acceptable with the proviso that those that can release histamine (now rarely used) should be titrated in small increments. Introduction of inhaled anesthetics or the use of shorter-acting intravenous agents can be undertaken as guided by observation of the surgical field. If N2O is contemplated at any time, the anesthesiologist must remember the possibility, in the setting of missile injury or compound skull fracture, of intracranial air. The anesthesiologist should appreciate that the priority is to open the cranium as rapidly as possible. An arterial line, often placed after induction in urgent situations, is appropriate for essentially all acute trauma craniotomies. The concept that the injured brain is extremely vulnerable to what would otherwise be a minor insult. Some institutions, which have the necessary data analysis capacity, take another approach to targeted therapy. When establishing normovolemia alone does not accomplish that objective, phenylephrine, norepinephrine, and dopamine have all been used. The use of hypocapnia has been reviewed in detail in the section Management of Paco2. Once again, the anesthesiologist should agree on management variables with the surgical team at the outset of all procedures. The important principles are that fluids should be chosen invariably to prevent reduction of serum osmolarity and should probably be chosen to prevent profound reduction of colloid oncotic pressure-that is, in the circumstances of a large-volume resuscitation (arbitrarily, greater than half a circulating volume), using a mix of colloids and crystalloids is probably appropriate. A chronic negative fluid balance, as can occur with the combination of modest fluid restriction and liberal use of osmotic diuretics, has been shown to be deleterious and should be avoided. The use of hypertonic solutions and the relevant attributes of colloid solutions were discussed in the section Intravenous Fluid Management. There is relatively little information to provide guidance (also see Chapters 61 and 105). However, PbtO2 monitors suffer from the inverse of the problem that prevails with SjvO2 monitoring: they provide very focal information about the oxygenation status of only small regions of brain surrounding the tip. If they are placed remotely from focal injuries to provide a global measure of oxygenation, they may not see adverse events in at-risk but salvageable perilesional tissue. In the ideal situation, neurosurgical consultation is readily available and, appropriately, the anesthesiologist rarely has to make the decision for surgery. It may, however, be necessary for the anesthesiologist to participate in this decision. Excessive comfort should not be taken Monitoring jugular veNouS oxygeN SaturatioN. An SjvO2 less than 50% for 5 minutes is commonly accepted as constituting jugular desaturation. It might be expected to have limited sensitivity to focal events, and instances in which focal inadequacy of perfusion was not reflected by low SjvO2 have been reported. Delayed deterioration has been observed as much as 4 days after the initial injury. This section reviews the cardiovascular events associated with direct stimulation of the brainstem and their possible implications for postoperative management. Brainstem Stimulation Irritation of the lower portion of the pons and the upper medulla and of the extra-axial portion of the fifth cranial nerve can result in a number of cardiovascular responses. The former two areas are most often stimulated during procedures on the floor of the fourth ventricle and the last during surgery at or near the cerebellopontine angle. The responses may include bradycardia and hypotension, tachycardia and hypertension, or bradycardia and hypertension, and ventricular dysrhythmias. Pharmacologic treatment of the dysrhythmias that occur may serve to attenuate the very warning signs that should be sought. Irritation and injury of posterior fossa structures that may have occurred during surgery should be taken into account in planning extubation and postoperative care. In particular, procedures involving dissection on the floor of the fourth ventricle entail the possibility of injury to cranial nerve nuclei or postoperative swelling in that region, or both. The posterior fossa is a relatively small space, and its compensatory latitudes are even more limited than those of the supratentorial space.

Many such agents do not pose a significant threat by inhalation allergy treatment immunotherapy buy generic seroflo 250mcg, but may be absorbed through the epithelia allergy symptoms in 1 year old purchase cheap seroflo on line. Most classic biologic warfare agents have low persistency allergy treatment without medication generic seroflo 250mcg free shipping, being rapidly degraded by the environment allergy symptoms nasal drip seroflo 250mcg with amex, and depend on host transmission via an incubation period allergy forecast dublin buy seroflo american express. Anthrax is a notable exception; its spores have very long persistency allergy rash on baby 250 mcg seroflo with mastercard, but no infective transmissibility. At the other extreme, the viral hemorrhagic fevers have very short persistency but high infective transmissibility. As Box 83-7 shows, several levels of protection are used in the management of toxic releases, but the appropriate level for medical intervention is level C, which allows reasonable tactile dexterity and contact with the patient to provide essential life support and antidote therapy onsite. Patterns of signs and symptoms manifesting in victims may be the first indication of the nature of the causative agent. A toxic release is a special case of disaster and may be either accidental or deliberate. The importance of risk assessment: Not all listed hazards are identifiable risks 2. Special triage, decontamination, and resuscitation center set up at a Parisian teaching hospital. Early life support measures in the decontamination zone are very important123 (see also Chapter 107). In the unconscious casualty, this may involve simple basic airway maneuvers plus suction of the copious secretions associated with chemical poisoning. Occasionally, advanced airway management, such as tracheal intubation, may be required to protect the airway from the excessive secretions and to prevent aspiration of regurgitated stomach contents. If breathing becomes compromised, artificial ventilation with supplemental O2 must be administered using a self-inflating resuscitation bagvalve-mask or automatic ventilator. Entrained air must be filtered when ventilating casualties in a contaminated environment. Noninvasive blood pressure, pulse oximetry, and electrocardiogram monitoring are all useful indicators of circulatory function. The early establishment of intravenous access aids the administration of fluids and drugs. This assessment should be repeated at frequent intervals to assess the progress of the casualty. Drugs, especially the specific antidotes, should be administered when a specific agent has been identified. Exposure of the casualty is essential not only to assess physical damage, but also to remove all clothes that have been contaminated by the chemical. The primary management as described may be severely limited by the need for the rescuer to wear protective clothing. Only those skilled in these techniques and trained in protective clothing should enter and treat casualties in a contaminated area. Somatic Systems Affected by Toxic Hazards Early patient management is based on (1) identification information and (2) the manifesting signs and Chapter 83: the Role of the Anesthesia Provider in Natural and Human-Induced Disasters 2509 symptoms. Usually information will be available to help with identification of the agent used. On the basis of manifesting signs and symptoms, it is useful to consider attacks on the various clinical systems as guide to the agent used (Table 83B-6). Okumura T, et al: the dark morning: the experiences and lessons learned from the Tokyo subway sarin attack. In Handbook of experimental pharmacology, the neuromuscular junction vol 42, Berlin, 1976, Springer-Verlag, p 487. Koelle G, editor: Handbook of experimental pharmacology, cholinesterase and anticholinesterase agents, vol. Many of the agents described earlier affect the condition of the patient and the action of anesthetic agents. The respiratory uptake of anesthetic vapors and alveolar ventilation itself are affected by degrees of shunt and pulmonary edema. Above all, the action of toxic agents may be expected to alter the balance and flow of general anesthesia and may cause delays in recovery, which would be labor-intensive in management. Many of the infectious agents considered biologic warfare agents can cause infections and even an overwhelming inflammatory response and organ dysfunction. Intensive care is required for cases of systemic inflammatory response syndrome and multiple organ dysfunction syndrome cases (see also Chapter 100). The continued possibility of an avian flu pandemic highlights the need to provide simple mass ventilation systems in high-dependency units. United Nations: Report of the mission dispatched by the secretary general to investigate allegations of the use of chemical weapons in the conflict between the islamic republics of Iran and Iraq. Noji E: Public health consequences of disasters, Prehosp Disaster Med 15:147-157, 2000. Guerisse P: Basic principles of disaster medical management, Acta Anaesth Belg 56:395-401, 2005. A health system framework for foreign medical teams in earthquakes, Prehosp Disaster Med 27:90-93, 2012. Tanaka K: the Kobe Earthquake: the systems response: a disaster report from Japan, Eur J Emerg Med 3:263-269, 1996. Perez E, Thompson P: Natural hazards: causes and effects-Lesson from two earthquakes, Prehosp Disaster Med 9:260-269, 1994. An outcomes-level assessment of use at a mass casualty event, Ann Emerg Med 14(Suppl):S12, 2007. Missair A, Gebhard R, Pierre E, et al: Surgery under extreme conditions in the aftermath of the 2010 Haiti earthquake: the importance of regional anesthesia, Prehosp Disaster Med 25:487-493, 2010. Okumura T, Nomura T, Suzuki S, et al: the Dark Morning: the experiences and lessons learned from the Tokyo subway sarin attack. Hobbiger F: the pharmacology of anticholinesterase drugs, Handbook of experimental pharmacology, vol. Cholinesterase and anticholinesterase agents, vol 15, Berlin, 1963, Springer Verlag. Stockholm International Peace Research Institute: the problem of chemical and biological warfare. Balali Mood M: Clinical and laboratory findings in Iranian fighters with chemical gas poisoning, Arch Belg 254(Suppl), 1984. Colardyn F, de Keyser H, Ringoir S, et al: Clinical observations and therapy of injuries with vesicants, J Toxicol Clin Exp 6:237-246, 1986. United Nations: Report of the mission dispatched by the Secretary general to investigate allegations of the use of chemical weapons in the conflict between the islamic republics of Iran and Iraq. Okumura T, Suzuki K, Fukada A, et al: the Tokyo subway Sarin attack: disaster management. In Laralliedde L, Feldman S, Henry J, et al, editor: Organophosphates and health, London, 2001, Imperial College Press. Bey T, Deynes S: the differentiated tactical and therapeutical approach to nerve agents of the same chemical class as a result of their different physical, chemical physiological properties, Prehosp Disaster Med 22:S153, 2007 (abstract). Kato T, Hamanaka T: ocular signs and symptoms caused by exposure to sarin gas, Am J Ophthalmol 121:209, 1996. Marrs T, Rice P, Vale A: the role of oximes in the treatment of nerve agent poisoning in civilian casualties, Toxicol. Worek F, Eyer P, Kiderlen D, et al: Effect of human plasma on the reactivation of sarin-inhibited human erythrocyte acetylcholinesterase, Arch Toxicol 74:21-26, 2000. Williams P, Willens S, Anderson J, et al: Toxins: established and emergent threats. Anil Patel, who was a contributing author to this topic in the prior edition of this work. Nitrous oxide must be avoided for 7 to 45 days after use, or until the gas bubble is resorbed. The wall of the globe has three layers: the sclera, the uveal tract, and the retina. The middle layer, the uveal tract, has three structures: the choroid, the iris, and the ciliary body. The pigmented iris controls light entry with muscle fibers that change the size of the pupil. Sympathetic stimulation dilates the pupil by causing iris dilator muscles to contract, whereas parasympathetic stimulation causes miosis, or pupillary constriction, by causing the iris sphincter muscles to contract. Ciliary muscle fibers adjust the focus by releasing tension on the suspensory fibers, or zonules, of the lens. Uveitis is an inflammatory condition of these structures (iris, choroid, and ciliary body). Light stimulates retinal photoreceptors to produce neural signals that the optic nerve carries to the brain. There are no capillaries in the retina; the choroid layer provides the retina with oxygen. Retinal detachment from the choroid layer compromises the retinal blood supply and is a major cause of vision loss. The area between the limbus of the cornea and the retina is called the pars plana. Because there is no retinal layer there, it is a safe entrance site for vitrectomy procedures. Traction of the vitreous on the retina is a cause of 2512 Chapter 84: Anesthesia for Eye Surgery 2513 retinal detachment. They arise from a fibrous ring near the apex of the orbit and insert on the sclera. The six extraocular muscles lie within a cone behind the eye surrounding the optic nerve, ophthalmic artery and vein, and ciliary ganglion. The eyelids have an outer layer of skin, a muscle layer, a tarsal plate of cartilage, and a layer of conjunctiva. The conjunctiva is a mucous membrane that lines the inner eyelids and covers the globe up to the corneal-scleral junction. Tears flow through the canaliculi to the lacrimal sac and duct, to drain into the nasopharynx. The ophthalmic artery provides most of the blood supply to the orbital structures. The superior and inferior ophthalmic veins drain directly into the cavernous sinus. The nasociliary branch of the ophthalmic nerve sends sensory fibers to the medial canthus, lacrimal sac, and ciliary ganglion. The ciliary ganglion provides sensory innervation to the cornea, iris, and ciliary body. Sympathetic fibers originate from the carotid plexus and travel through the ciliary ganglion to innervate the dilator muscle of the iris. Local anesthetic blockade of the ciliary ganglion produces a fixed, mid-dilated pupil. In the event of arrhythmia, the anesthesiologist first should ask the surgeon to stop manipulations. If significant bradycardia persists or recurs, intravenous atropine is administered in 7-g/kg increments. Although chest compressions might be required to allow the atropine to circulate, usually the heart rhythm returns to normal with cessation of manipulation alone. Pretreatment may be indicated in patients with a history of conduction block, vasovagal responses, or -blocker therapy. The volume of the internal structures is fixed except for aqueous fluid and choroidal blood volume. Two thirds of the aqueous fluid is actively secreted by the ciliary body by a sodium-pump mechanism. Aqueous fluid flows over the lens and through the pupil to bathe the inner corneal endothelium. It then enters the angle of the anterior chamber to flow through the trabecular meshwork to the canal of Schlemm. Sclerosis of the trabecular meshwork is believed to cause the chronic pressure elevation in openangle glaucoma. Closed-angle glaucoma occurs when there is an obstruction to aqueous drainage from closure of the anterior chamber angle. The acute increase in pressure causes severe pain and is an ophthalmologic emergency. In particular, it is seen with traction on the medial rectus muscle, but it can occur with stimulation of any of the orbital contents, including the periosteum. The afferent limb is from orbital contents to ciliary ganglion to ophthalmic division of the trigeminal nerve to the sensory nucleus of the trigeminal near the fourth ventricle. The use of succinylcholine for induction of anesthesia in cases of open-globe injury with full stomach has been controversial. Tamsulosin hydrochloride (Flomax) has selective -adrenoreceptor antagonistic properties and binds for a long period to nerves to the iris dilator muscle, affecting iris dilation and leading to complications in cataract surgery. The iris remains floppy even after a 7- to 28-day interruption of the tamsulosin regimen. In 2005, the Medicare program paid for nearly 3 million claims for cataract surgery. These outpatient procedures are quick and do not involve blood loss or significant postoperative pain. They are not minor procedures, however; ophthalmic surgery can be a major life event. Establishing a professional relationship reduces anxiety and helps the patient prepare for surgery. Giving information to the patient is just as important as getting information from the patient.