By M. Sugut. University of Alaska, Fairbanks.

Chapter 26 Recovery of Function of the Nervous System: Plasticity and Regeneration 335 nucleus to an eccentric location adjacent to the When regenerating axons are challenged to grow cell membrane and often directly across from the across an injury site where the proximal and axon hillock purchase clomid with paypal women's health issues in the 19th century. Secondary to altered ionic pump distal nerve stumps are spatially separated buy generic clomid women's health bikini body meal plan, the properties and resultant changes in membrane chances for functional recovery become dimin- permeability, the soma swells. Most characteris- ished and largely depend on the distance between tic is the dissolution of the dense clumps of rough the two nerve ends. In clean-cut types of injury, endoplasmic reticulum or Nissl bodies leading for example, a razor blade or sharp knife, the to chromatolysis or loss of basophilic staining. Finally, synaptic boutons disconnect from of the larger nerve fascicles can be approximated the dendrites and soma of the now dysfunctional and oriented such that the regenerating axons neuron. Functional recovery is vival of an axotomized neuron: proximity of least likely after nerve injuries such as gunshots, injury site to the cell body and the correlated loss in which a relatively long segment of the nerve of axoplasm, proportion of surviving collateral is obliterated. Under these conditions, strategies projections providing access to target-derived to surgically repair the injury can include the trophic factors, and fnally, age of the patient approximation and suturing of the proximal and with evidence that damage in the young is more distal nerve stumps by positioning and fxating deleterious than in the old. Other continued degeneration has not been crossed, treatments to bridge the gap between proximal axotomized neurons will attempt to regenerate and distal nerve stumps include the grafting of their axon from the site of injury distally. In all cases, it is critical to bring the proximal end of a severed stump and contin- proximal and distal nerve stumps within several ues with the addition of new axonal membrane millimeters of each other because the diffusion at the leading edge of the regenerating axon. Beginning 3 to 4 days after injury, mitogens Clinical released by invading macrophages trigger the division of Schwann cells along the length of Connection the nerve segment. Chemoattractants or tropic A neuroma can develop at the substances released by Schwann cells provide site of peripheral nerve injury guidance signals for regrowing axons to extend when regenerating sensory axons fail to reen- distally. Blindly ending sensory The degree of functional regeneration largely axons can be activated by nonphysiologic depends on the type of injury. This phenomenon is sive or ischemic nerve injury in which the neu- considered the basis for phantom limb pain. Regenerating axons grow into the tube ating axons would grow into any vacant distal they originally occupied. Spinal trauma can result in Axons regenerate 1 to 2 mm/day, the rate the formation of a central cavity surrounded by of slow axoplasmic transport. On reaching the a rim of intact tissue or alternatively a complete distal end of the neurolemmal tube and the separation of the spinal cord. In either type of effector muscle or gland for a motor axon, or injury, there is a signifcant gap that regenerat- a receptor for a sensory axon, functional con- ing axons must bridge to grow to distant targets. Once reconnected, Finally, three proteins in the oligodendroglial trophic signals are conveyed retrogradely to the membrane of myelinated central axons inter- cell body where, over time, the morphologic act with a single receptor (Nogo) on the lead- organization of the cell returns to normal and ing edge of regenerating axonal growth cones. Basic research during the past 40 years in to regenerate, but a number of extrinsic factors animals and more recent functional imaging preclude functional reinnervation. Spinal cord studies in humans have shown the nervous sys- injury best illustrates these constraints. Plasticity site of spinal injury, reactive astrocytes divide or in both neuronal morphology and electrical enlarge to form an impenetrable physical bar- responsiveness occurs with normal changes in rier or glial scar around the injury site to pro- the internal milieu of the nervous system, with tect degeneration and infammatory reactions external changes in environment, and with from spreading into undamaged areas as well as behavioral adaptations, as well as with injury to reestablish the blood-brain barrier. Generally, new synaptic connections only Connectional plasticity can be simple changes form by reactive synaptogenesis, in which synapses in synaptic effcacy such as that which occurs lost as the result of injury are replaced by terminal presynaptically in short-term facilitation and sprouting from surviving axons in the immediate posttetanic potentiation or occurs postsynap- area (Fig. Quantitative studies of reactive tically with long-term potentiation and long- synaptogenesis in adult animals have convincingly term depression. Morphologic changes can shown that new synapses formed by surviving include presynaptic remodeling of axonal ter- afferent terminals are very similar in both num- minal arbors or postsynaptic distal dendrites or ber and physiologic effcacy to the lost synaptic dendritic spines. Surviving homologous afferents (from Lesion-Induced Plasticity the same system) have the highest preference for replacing lost inputs, followed by nonhomolo- As neurogenesis in the adult is very restricted, gous but functionally related surviving afferents limited to the birth of new primary neurons in (e. Surfeit or exuberant connections develop along with axonal circuits that normally persist into Clinical the adult. When these latter connections are Connection damaged, the normally transient axonal pro- jections can persist and maintain synaptic Two examples illustrate the plas- input to target neurons. As the result of ongo- ticity of the adult sensory sys- ing growth-related gene expression, undam- tems. First, after amputation of a digit, the aged axons of immature neurons can develop cortical area of representation for the lost digit additional axonal terminal arbors or collat- is replaced by sensory inputs expanding from eral sprouts as well as redirect axonal growth the immediately adjacent representation areas to denervated targets. Regenerative sprouting of intact digits, thereby increasing the cortical of terminal arbors or more distant collaterals “sensitivity” for these digits. New sensory plasticity occurs in blind patients or regenerating axons can grow up to several trained to “read” braille. This new or regen- edly have greater tactile discrimination resolu- erated axonal growth is also possible because tion in the fngerpads compared with sighted axonal growth inhibitory molecules, present in individuals. In addition, sound localization and the adult, have not yet developed to the point speech discrimination are enhanced in blind that they form a nonpermissive environment individuals compared with sighted individuals. Chapter 26 Recovery of Function of the Nervous System: Plasticity and Regeneration 339 26-10. A small stroke in the dorsolateral part of Chapter Review the right rostral medulla results in the loss Questions of coordinated movements of the lower limb on the same side. What are the characteristic tion and amelioration of the ataxia neurohistologic changes in the cell body b. What three factors preclude successful peduncle axonal regeneration in the central d. What type of injury to a peripheral nerve would predictably result in the greatest 26-11. You are assigned to oversee the result of either compression injury or postoperative management of the patient. A 47-year-old secretary presents with neurons because of the proximity of the tingling and pain in both hands for injury to the neuronal cell bodies months. The most likely diagnosis sensations are especially prominent for this condition is: at night often preventing her from a. The most impor- the area of peripheral distribution of the more tant long pathways in the brainstem and spinal rostral spinal cord segments below the lesion, cord are the pyramidal tract, the spinothalamic but not the more caudal. This “sacral sparing” tract, the dorsal column-medial lemniscus path, and the spinal trigeminal tract. Long pathways in the cerebral hemispheres are the pyramidal and corticobulbar tracts, the somatosensory thalamic radiation, and the visual pathway. The level of a spinal cord lesion may be determined by the loss of functions in dermatomes and myotomes. The key to localizing lesions in the spinal cord is the loss of motor or sensory functions or both below the foramen magnum, that is, in the area of distribution of the spinal nerves. This phenomenon usually pathways, that is, the more rostral spinal nerves results from syringomyelia or cavitation of the are represented internal to the more caudal spinal cord and is called the commissural syn- (Fig. Lesions pyramidal or corticospinal tract, spinothalamic involving the ventral white commissure result tract, medial lemniscus, spinal trigeminal tract, in the loss of pain and temperature sensations and the superior cerebellar peduncle. Pain T10 Loss of Spastic paralysis and pain and loss of tactile temperature vibration, and senses proprioception senses Figure 27-3 Left hemisection of spinal cord at T10. Spastic paralysis and loss of tactile, vibration, and proprioceptive senses on left (L, ipsilateral) side and loss of pain and temperature senses on right (R, contralateral) side.

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In addition purchase clomid 50 mg with amex contemporary women's health issues for today and the future 5th edition, holding cells for rioters that have been arrested along with people to guard them will be in short supply buy 25mg clomid amex women's health clinic rock springs wy. Stage 5 of the Disaster Due to all of the confusion, the governor, after 2 days of rioting, has now asked for 3,500 federal troops to be deployed from Fort Ord. The troops are fnally deployed on May 2 (Suburban Emergency Management Project, 2004). The city manager should see if the additional troops can be sent to areas where the rioting is the worst and be integrated with the National Guard’s eforts to combat the rioters. Funds will need to be raised and budgets will need to be adjusted to clear out debris and repair infrastructure. The frst order of business will be to fnd shelter and provide supplies to those that are now homeless. A second focus will be to fnd those responsible for the rioting, arrest them, and pros- ecute them to the fullest extent of the law. Key Issues Raised from the Case Study A major metropolitan city should have an efective organizational structure in place to contend with such an occurrence. The decision-making process should be seam- less when dealing with a rioting crowd, and plans should be in place to obtain more resources and make the most use of those resources quickly. As seen in this case study, the command and control center was not unifed, which led to an even more dysfunctional situation in responding to the rioting. By not deploying the National Guard troops in a timely fashion, the administrators allowed for more devastation to occur to more parts of the city. Case Studies: Shootings and Riots ◾ 183 Items of Note The Los Angeles Riots ultimately cost the lives of 53 people (Gray, 2008). Columbine High School Massacre, Colorado, 1999 Stage 1 of the Disaster You are the superintendent of a suburban school district in the United States. The superintendent needs to immediately have the local police dispatched to the high school and make sure that students, staf, and teachers are being evacuated out of the school. The superintendent needs to provide the police and fre department with an accurate foor plan of the high school that may help the frst responders contend with the emergency more efectively. The superintendent should be coordinating eforts with the local police department, fre department, and hospitals to provide medical support if it is needed. The superintendent at this point cannot really do much except request the local police department to mobi- lize units to the high school. In addition, the hospitals must be contacted to provide medical services, and the fre department may be needed in case the gunmen have more than just frearms for weapons (i. The communication plan will be limited since there is little information for the superintendent to relay to anyone. Gunshots are still being heard outside the high school from the second foor around where the library is located (Steel, 2008). The super- intendent will need to fnd as many teachers and administrators as possible to account for students that were in their classes at the time of the attack. Hopefully, the superintendent can get an accurate head count of who may still be in the high school from teachers and staf. In addition, the superintendent will need to have some mechanism in place to notify families of their child or employee’s condition in case they were hurt or killed by the gunmen. A public afairs ofcial for the district should be on hand to report the status of the situation to the parents and community. At this point, you know there are some stu- dents and teachers that have been killed or wounded by the gunmen. The superintendent is going to have to come up with a plan to move forward after this tragedy has occurred. What to do about the high school will be a very emotional decision after an occur- rence like this has unfolded. The superintendent will also need to address security policies, precautions, and procedures that are currently in place at the district’s other schools in order to reevaluate their efectiveness. The superintendent will need to make a public statement on what occurred at the high school and what will hap- pen going forward. The superintendent needs to make sure that the public is aware that change will be coming to make the schools safer in the future from having such a situation occur again. Key Issues Raised from the Case Study Tere is very little that a public school can do in the event of such an occurrence except to have an efective evacuation plan in case an armed gunman enters the school. In this case the problem is complicated by the fact that the gunmen were students and it would have been extremely difcult to detect their intentions by school employees until it was too late since they were outside the building when their explosive devices detonated. Unless early warning signs are heeded that students may have mental illness and could possibly be violent, administrators run the risk of a violent incident occurring Case Studies: Shootings and Riots ◾ 185 in their organization. If action is taken proactively against potential violent indi- viduals, a crisis can potentially be averted. Items of Note The Columbine High School massacre resulted in 13 students and teachers killed and 25 injured. Beltway Sniper Attacks, 2002 Stage 1 of the Disaster You are a governor for an East Coast state in the United States. Since the killings appear to be the act of a single killer, the state police need to be notifed to keep a lookout for any suspicious activity. The state police and local police departments need to coordinate eforts in an attempt to fnd the gunman or gunmen responsible. The resource needed at this point is an analysis from the crime scenes to determine and verify if the victims were all killed in the same manner, and if so, what type of weapon was used. In addition, manpower needs to be deployed to begin hunting the perpetrators down that are responsible for this crime. The state police force should work with county and local law enforcement agencies in an efort to track down the gunman or gunmen responsible for the attacks. The population should be informed of the sit- uation and asked for their assistance in trying to capture the wanted criminals. All of the killings on those 2 days were caused by a bullet shot from a great distance by a sniper (Mansbridge, 2003). Another appeal to the public should be made in an efort to capture the sniper to provide information that may assist law enforcement. In addition, resources such as security cameras, helicopters, and aircraft need to be used to observe areas where the sniper appears to operate. Key Issues Raised from the Case Study Tis case study is an example of how deadly a sniper can be when he or she is a skilled marksman, has an accurate and reliable weapon, and is highly mobile. Tis type of attack is almost impossible to prevent if the sniper has the initiative and there is no basis to detect this type of individual from bringing a weapon into the area. If a sniper takes a shot from a long distance away, the individual could be gone from the entire area before frst responders appear on the scene. It may have taken a while for law enforcement to catch the snipers in this case, but overall this case study demonstrates how law enforcement must use patterns to interdict and arrest such individuals. Administrators need to be aware that attempting to apprehend such individuals may take time, patience, and a good search strategy. Administrators must also be aware that attempting to apprehend such individuals will take quite a few resources to perform a search and set up checkpoints on major roadways. John Allen Muhammad was sentenced to death and executed, while his accomplice, Lee Boyd Malvo, was sentenced to life in prison without parole in 2003 (Calvert, 2009).

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However 50 mg clomid visa women's health center gretna, in a large (313 patients) multicenter study with a median duration of follow-up of 12 generic clomid 50 mg without a prescription menstrual yoga. In this cohort, nearly all patients were noted to have adequate surgical relief (median 76 mm Hg preoperatively to 15 mm Hg postoperatively) and there was an overall increase in the gradient of 1. Patients with discrete membrane or fibromuscular ridge have usually undergone surgery by adulthood, however, these lesions have a tendency for re-growth and concomitant aortic valve disease (54). A large retrospective study of 75 patients postsurgical resection found in a recurrence rate of 16% at 5 years and 30% at 10 years. Patients with a higher preoperative gradient (>40 mm Hg), higher postoperative gradient (>10 mm Hg), and younger age at surgery were predictors for recurrence (55). Additionally, the need for aortic valve repair and the progressive aortic insufficiency occurred less often in those with a lower preoperative gradient. This finding has led some to recommend early repair of fixed subaortic obstruction prior to the development of high gradient or aortic valve disease (55). However, there was a slightly higher incidence of postoperative heart block in the myectomy group (56). Coarctation of the Aorta Coarctation of the aorta is a narrowing of the descending aorta, which is typically located at the insertion of the ductus arteriosus just distal to the left subclavian artery. All patients with coarctation (repaired or not) should be monitored with lifelong congenital cardiology follow-up and imaging because long-term survival is reduced compared with normative populations and there is potential need for reintervention. A long-term follow-up study of patients repaired in childhood or adolescence demonstrated a significantly reduced long-term survival—mean age P. The largest single-center series describing long-term outcome included 819 patients (mean age at repair 17. The survival rates were 93%, 86%, and 74% at 10, 20, and 30 years after primary repair, respectively (58). Systemic Hypertension Systemic hypertension is one of the major long-term problems following repair of coarctation of the aorta. Although the blood pressure typically falls after successful repair, persistent or recurrent hypertension and disproportionate systolic hypertension with exercise are observed, especially in patients whose repair is performed later in life. Although the blood pressure typically falls after successful repair, persistent or recurrent hypertension and disproportionate systolic hypertension with exercise are not uncommon. Hypertension and left ventricular hypertrophy are among the factors that contribute to premature death from coronary and cerebrovascular disease in patients with a surgically repaired coarctation (57). The factors responsible for the persistent risk of hypertension after coarctation repair are not well understood. Among the probable contributing factors are structural and functional abnormalities that decrease compliance in the precoarctation arterial wall. Also, increased ventricular stiffness, left ventricular hypertrophy, and a hypercontractile state in postrepair patients may play a contributory role (59). Multiple studies have found a significant incidence of systemic hypertension either at rest or with exercise following repair (60,61,62,63). When combining resting blood pressure, ambulatory blood pressure monitoring and exercise testing, systemic hypertension has been reported in as many as 70% of patients following coarctation repair (64). Hypertension may occur irrespective of the age at surgery or the presence of a residual gradient. Patients who had delayed initial repair often have residual hypertension despite surgical or transcatheter intervention. Recoarctation should be evaluated for transcatheter therapy (stent, angioplasty)— see adult congenital heart disease interventional therapy section. If there is no evidence of recoarctation, then medical management for hypertension is indicated. Recoarctation Recurrent recoarctation refers to restenosis after an initially successful intervention. Often the major findings suggest that a patient has developed recoarctation are resting hypertension and headaches, though some patients could still be asymptomatic. It is seen primarily in children usually due to inadequate aortic wall growth at the site of repair when surgery is performed before the aorta has reached adult size. Following balloon angioplasty, children are also at greater risk for recoarctation compared with adults. Most patients with recoarctation will undergo an evaluation for transcatheter therapy to relieve the aortic obstruction (see section on adult congenital heart disease interventional therapy). Discrete coarctation in older children and adults is treated with percutaneous balloon angioplasty, often with stent therapy (12,68,69). Eiken reported that despite successful stent therapy the patient may still demonstrate systemic hypertension requiring medical therapy, once again attesting to the intrinsic abnormality associated with coarctation of the aorta (70). Aortic Aneurysm/Pseudoaneurysm An aortic aneurysm may develop at the site of prior coarctation following surgery (especially after patch angioplasty), balloon dilation, or stent implantation of native coarctation (71). Development of aortic aneurysm and rupture may occur years after successful repair of coarctation of the aorta (39,40,41,42). Risk factors for postrepair aneurysms are age at the time of coarctation repair (≥13. The risk of dissection is increased during pregnancy, which is associated with hemodynamic, physiologic, and hormonal changes superimposed on the pre-existing aortic wall medial changes. This finding appears to occur without recurrent coarctation and despite relief of systemic hypertension (Fig. For the majority of patients, aneurysm repair requires surgical intervention with resection of the aneurysm and graft placement. Alternatively, endovascular stent grafts have been used to repair aortic aneurysms at the site of prior coarctation repair. At this time, there are no criteria to guide the timing of aortic aneurysm repair in this population. Pseudoaneurysms are at a higher risk for rupture and should be considered for repair at P. Either surgical repair or in selected cases, excluding the aneurysm with a covered stent should be employed to remove the risk of pseudoaneurysm rupture (Fig. Though risk factors for postrepair aneurysms have been identified, including a later age at initial repair and the use of patch angioplasty, there are no clear risk factors for the higher incidence of hypertension and aortic dissection following coarctation repair. However, a growing body of evidence demonstrates that there is an intrinsic abnormality of aortic function that persists despite adequate repair (43). A stiff or less distensible aorta has been described with essential hypertension, coronary artery disease and Marfan syndrome, and may be the underlying mechanism contributing to the late abnormalities associated with repaired coarctation of the aorta (76). Documenting the type of repair performed is important in the evaluation of this population. Most underwent patch aortoplasty, resection of the coarctation with end-to-end anastomosis or subclavian flap repair. However, a small percent have undergone bypass tube grafting around the coarctation segment. A clear understanding of the type of repair will aid in the diagnosis of complications and when follow-up studies are necessary (Fig.

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This chapter discusses the indications for heart transplantation quality 25 mg clomid menstrual upset stomach, various phases of the transplant process (preoperative buy genuine clomid online menstrual pain relief, early postoperative, and late), the immunosuppressive drugs, the role of heart and lung transplantation, and the issue of retransplantation. The registry of the International Society for Heart and Lung Transplantation: seventeenth official pediatric heart transplantation report–2014; focus theme: retransplantation. A comprehensive history and physical examination is mandatory, including age, height, weight, and body surface area. Since pediatric heart donors are matched with recipient size, accurate measurements of the recipient are critical and need to be continually updated in those who wait long periods of time and undergo changes in their height or weight. Cardiac diagnoses, including all previous surgeries, must be meticulously delineated, with particular attention to venous and arterial connections, since the surgeon will need this information in order to devise a surgical plan in those with complex congenital heart disease with abnormal connections. The use of extended donor heart and vessel retrieval and creative intraoperative techniques has resulted in successful orthotopic heart transplantation in children with abnormal situs and/or significant systemic and pulmonary venous anomalies (2,11). Immunization status should be determined, and if incomplete prior to listing for transplant, immunizations may be given as indicated by age (12,13). A history of malignancy, once considered to be an absolute contraindication to transplantation, may not preclude transplantation in selected patients (14,15). A thorough laboratory evaluation is necessary to determine liver and kidney function since severe, irreversible liver or kidney dysfunction would generally exclude the child from consideration for heart transplantation, although some centers may consider multiple organ transplants. An accurate and documented blood type is critical since this is usually the main compatibility factor used for donor/recipient matching. However, this can severely limit the donor pool available to a recipient and increases mortality waiting for transplant in those awaiting a compatible donor (17,21). Cardiac catheterization and angiography should be performed as part of the pretransplant evaluation by someone experienced in the diagnosis and treatment of pediatric cardiovascular disease and heart transplantation. Especially in patients with complex congenital heart disease, hemodynamic and anatomic assessments are critical for appropriate pretransplant evaluation. In addition to precise anatomic and hemodynamic definition, it is necessary to determine whether other pharmacologic, catheter interventional, or surgical options may be necessary prior to transplantation. Patients with univentricular physiology, particularly those who have undergone multiple palliative procedures, are a P. For example, children after the Fontan operation may have many complications such as dysrhythmias, protein-losing enteropathy, cirrhosis, and/or low cardiac output that may bring them to transplant consideration. Assessment of pulmonary arterial anatomy, pressures and, when possible, pulmonary vascular resistance is critically important in the pretransplant evaluation of most children being assessed for heart transplantation. Severe, fixed elevation of the pulmonary vascular resistance is a contraindication to orthotopic heart transplantation because of concerns of acute posttransplant right ventricular failure. Both elevated transpulmonary pressure gradient and elevated pulmonary vascular resistance have been identified as risk factors for early mortality after heart transplantation (30). However, a previous multi-institutional analysis of risk factors for mortality in children >1 year of age at the time of transplantation did not find elevated pulmonary vascular resistance to be a risk factor (31). The current selection criteria for pediatric orthotopic heart transplant recipients exclude those patients with significantly elevated nonreactive pulmonary vascular resistance (3,10). In these patients who are denied orthotopic heart transplantation, other options such as heterotopic heart transplantation, heart/lung transplantation, or lung transplantation with repair of the congenital heart defect may be considered (32,33,34). Accurate evaluation of the degree of pulmonary hypertension may not be possible in those patients with either discontinuous pulmonary arteries or multiple sources of pulmonary blood flow, or in those with multiple branch pulmonary artery stenoses. Several agents have been shown to have both acute and chronic beneficial effects in lowering transpulmonary gradients and pulmonary artery pressures in adults and children. Response to these agents, including intravenous nitroglycerin, nitroprusside, prostaglandin E1, dobutamine, enoximone, milrinone, in addition to inhaled nitric oxide, has been shown to predict outcome after heart transplantation (36,37,38,39,40,41). Mechanical circulatory support can also be considered in refractory cases (42,43). Children with restrictive cardiomyopathy appear to be at higher risk for development and rapid progression of significant pulmonary hypertension and thus require careful monitoring and possibly early consideration for heart transplantation (44,45,46) (see Chapter 56). Assessment of cardiac anatomy and function by a complete Doppler echocardiogram is a necessary part of the pretransplant evaluation. Endomyocardial biopsy may be indicated in certain instances, for example, to exclude active myocarditis or myocardial infiltrative diseases. Electrocardiograms and 24-hour continuous ambulatory electrocardiograms may be important in determining underlying rhythm, evidence of ischemia or previous infarction, and abnormal rhythms or intervals. A chest radiograph may be very useful for measuring the degree of recipient cardiomegaly to help in determining size limitations in potential donors. In older children, pulmonary function tests may be important, especially if there is any concern of chronic lung disease. In those who can cooperate, measurement of maximal O2 consumption may be very useful for quantifying the degree of cardiorespiratory compromise the patient is experiencing. A significantly reduced maximal O2 consumption <50% of that predicted for age may be considered evidence of compromise that should at least lead to consideration of heart transplantation as a therapeutic option (10,47,48). This diagnostic test may be less useful in those children with heart failure who have undergone the Fontan operation, since a significant number of patients in this group is unable to achieve maximal aerobic exercise capacity (49). A stable family support system that is emotionally and intellectually able to provide medications and posttransplant care is crucial to the success of the heart transplant. In many instances, it is necessary for the family to relocate to be in close proximity to the transplant center for the entire waiting period before transplantation and for 3 to 6 months after the transplant. It is uncommon to have an absolute psychosocial contraindication to pediatric heart transplantation. However, a family history of noncompliance, substance abuse, or child abuse or neglect may be a relative contraindication to transplantation. Financial needs and resources can vary considerably and should be thoroughly evaluated. Since the waiting time for donors is unpredictable, patients may wait for long periods of time, during which time ongoing pharmacologic, catheter interventional, and occasional surgical treatments must be used as needed. Patients may deteriorate rapidly while waiting for a suitable donor, in which case, more invasive measures may be necessary to bridge the patient to transplantation. Optimization of pretransplant nutritional status constitutes a strategy to reduce waitlist mortality in this age range (50). Early intervention may be the key in improving nutritional status and outcomes for patients both before and after transplantation (51). The epidemiology of infant heart transplantation has changed through the years as the results for staged repair of complex congenital heart disease have improved and donor resources have remained stagnant. Primary transplantation has remained available in some centers as a parental choice, and as the only solution for the occasional young infant with profound cardiomyopathic disease and inoperable complex congenital heart disease, including some tumors. Since waiting times for donors has increased at most institutions, there are increased challenges and problems associated with keeping these infants stable, sometimes for several months, before a suitable donor becomes available (54,55). Initial efforts must be directed toward opening and maintaining patency of the ductus arteriosus through the use of continuous infusion of prostaglandin E1. Once unrestricted ductal patency is achieved, therapy must be directed toward maintaining adequate systemic blood flow, sometimes through pharmacologic manipulation of the pulmonary vasculature (56,57).

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