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By N. Gelford. Gordon-Conwell Theological Seminary.

In the rare case requiring approach through a with aberrant left subclavian buy female cialis without prescription, 4 had a left aortic arch with right thoracotomy buy discount female cialis, the same principles are applied purchase female cialis 10mg without a prescription. There was one early postop- Video-Assisted Technique of erative death and no late deaths. At long-term follow-up three Management of Vascular Ring patients had residual symptomatic tracheomalacia, one of This has become the method of choice for all vascular rings whom required right middle and lower lobectomy for recur- unless preoperative studies suggest that there is a patent rent pneumonia. A similar conclusion was drawn by Bakker position following single lumen endotracheal intubation. There was no operative mortality after tive feld achieved by retracting the infated left upper lobe 1959. The ring is dissected free from patients had preoperative or intraoperative bronchoscopy. The atretic segment The technique of operation shifted to a muscle-sparing left thoracotomy without routine chest drainage. Clips are patients with right aortic arch and a Kommerell diverticulum, placed and the ring and ligamentum are divided between clips. Of note, there was transferred to the left carotid artery as a primary pro- are limited thorascopic options to plicate the diverticulum of cedure. Primary reimplantation of the left subclavian artery Kommerell as one could in an open approach. Due to the thin- for right aortic arch with Kommerell’s diverticulum is also walled nature of the diverticulum, suture plication via a thora- 22 recommended by Shinkawa et al. Seventy-fve % (135/180) were free from direct vision and the wounds are closed with Steri-strips. Postoperative Management Results of Video-Assisted Division of Vascular Ring In the young infant with severe respiratory symptoms, there In 1995, Burke et al. Therefore, it should be anticipated that not all age of 5 months underwent the procedure. Four had a double respiratory symptoms will be relieved immediately; in fact, aortic arch with atretic left arch and four had a right arch it may be several months before the child is free of stridor. All eight However, there should be complete and immediate relief of patients had successful ring division with symptomatic relief any diffculty with feeding. In three patients a limited thoracotomy was 656 Comprehensive Surgical Management of Congenital Heart Disease, Second Edition performed to divide vascular structures. Similar results complete tracheal rings, that is, the posterior membranous were described by Koontz et al. The complete rings may be localized to the region where the sling passes around the tra- In a patient with a typical pulmonary artery sling the left chea, although often they extend for the entire length of the pulmonary artery arises from the right pulmonary artery trachea. Severe stenosis can involve the carina and extend for and passes leftward between the trachea and esophagus (Fig. The left pulmonary artery is pulmonary artery is probably not the more important mecha- often relatively hypoplastic and considerably smaller than the nism of tracheal stenosis as suggested by the following expe- right pulmonary artery, which itself appears larger than nor- rience. Several years ago we managed a child at Children’s mal and almost like a direct extension of the main pulmonary Hospital Boston with a pulmonary artery sling in which artery. The small size of the left pulmonary artery may help the sling passed around the trachea above a very high “pig RecurrentRecurrent laryngeal n. The procedure is best performed through a median sternotomy employing cardiopulmonary bypass. Fortunately it is extremely Interestingly, in this child there was a tight, localized steno- rare for the anomaly to be diagnosed in the absence of symp- sis consisting of complete rings below the pig bronchus and toms because at present it remains unclear if surgery is indi- extending to the carina, although the sling lay entirely above cated in the absence of symptoms. There was no narrowing secondary to compression current practice would probably dictate surgical interven- in the region where the sling passed around the trachea. Symptoms of esophageal or, fnally, diffuse severe narrowing of the trachea related to compression are rarely present. Defnition of the vascular anatomy may be made in the same fashion as described for vascular rings. However, unlike surgicAl mAnAgEmEnt vascular rings, which produce a posterior indentation of the esophagus evident on barium swallow, pulmonary artery History slings produce an anterior esophageal indentation, which In 1954 Potts and associates described the approach to a can also be demonstrated on barium swallow. This was frst pulmonary artery sling using a left thoracotomy with divi- described by Wittenborg et al. This operation has not7 and area at various levels and demonstrates the presence of been widely practiced. Bronchography can produce spectacular imaging of described in 1986 by Kirklin and Barratt-Boyes. Improved cardiopulmonary bypass techniques (which ratory infection may be diffcult to clear completely before sur- allowed cumbersome intraoperative airway intubation tech- gery because of the diffculty in adequately clearing secretions. The ste- microvascular techniques have decreased the risk of tracheal notic segment of trachea, as defned by preoperative stud- anastomosis in the infant. The trachea is divided transversely ful application of cardiopulmonary bypass, tracheal resec- through the center of the stenotic segment (Fig. Serial sections taken similar tracheal resections for a wide variety of tracheal are taken of the two ends of the trachea until a satisfactory problems in infants since the late 1980s. This amount of resection allows anasto- integral part of the repair of pulmonary artery sling when mosis with little tension (Fig. It is important not to the sling is associated with important localized tracheal ste- compromise the amount of resection thereby leaving impor- nosis. The concern regarding devascularization which is important in adults appears not Although the original approach was through a left thora- to be relevant in children who have an excellent mediastinal cotomy, for many years we have preferred to undertake a blood supply. Great care, of course, should be taken during median sternotomy and use cardiopulmonary bypass (Fig. The tracheal anastomosis is under- an ascending aortic arterial cannula and a single straight taken with a continuous 5/0 or 6/0 polydioxanone or Maxon venous cannula in the right atrium. The absorbable monoflament sutures like mobilization of the main and right pulmonary arteries as polydioxanone and Maxon are also easier to work with than well as of the left pulmonary artery, thereby decreasing ten- 41 Vicryl which is braided. Furthermore, a side-biting clamp because of the absence of an endotracheal tube through the does not have to be applied for the anastomosis, because anastomotic area, the absence of clamps, and the strength cardiopulmonary bypass is employed. In fact, the presence of complete artery can be carefully and completely mobilized where it tracheal rings simplifes the anastomosis because of the passes around the trachea, allowing maximal length for strength of the tracheal cartilages. Care must be taken when dissecting poste- ponent is present posteriorly in the trachea, great care must rior to the trachea, particularly when complete rings are not be taken in this area allowing the tension to be absorbed by present, as there may be an intimate association between the suture bites through cartilage. When the anastomosis has left pulmonary artery and the membranous component of the been completed, the trachea is pressurized by the anesthe- trachea. When complete tracheal rings are present, the dis- siologist to 40 cmH O to test for air leaks. The anastomosis 2 section is less likely to injure the trachea and, in any event, is then wrapped with a fap of pedicled autologous pericar- it is likely that this segment of trachea will be excised. The dium, generally based on the right side of the pericardium, left recurrent laryngeal nerve must also be protected as it anterior to the right phrenic nerve. The The lie of the left pulmonary artery in its new location vascular anastomosis is constructed with continuous 6/0 or should be carefully observed. Blood fow is also less direct relative to a proximal takeoff from the Short Segment Tracheal Resection and Anastomosis main pulmonary artery.

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Depending on the severity of the stenosis buy female cialis with american express, the cardiac output cheap female cialis 10 mg, and the extent of the collateral circulation the systolic pressure gradient across a coarctation may be as high as 50 to 60 mm Hg at rest purchase 20mg female cialis amex. In many patients, a pressure gradient is present throughout systole and diastole (Fig. A variety of compensatory mechanisms assist the left ventricle in response to the increase in outflow impedance. Myocardial hypertrophy tends to normalize myocardial wall stress and ventricular afterload (27) and helps maintain normal systolic ventricular function. In isolated coarctation left ventricular end-diastolic volume is relatively normal, and the end-systolic volume may be reduced. Thus, left ventricular ejection fraction is normal to increased in most children with coarctation of the aorta (in the absence of heart failure). If a coarctation is severe or develops rapidly, as in a newborn upon ductal closure, left ventricular systolic dysfunction and heart failure may ensue. The hemodynamic consequences include diminished stroke volume, increased left ventricular end-diastolic pressure, elevated left atrial pressure, pulmonary venous congestion, and pulmonary artery hypertension. If cardiac output is severely compromised, diminished myocardial perfusion and the development of acidosis depress myocardial contractility further. Compensatory mechanisms include activation of the sympathetic nervous system (to increase heart rate and enhance myocardial contractility) and the Frank–Starling mechanism (to increase left ventricular end-diastolic volume and help maintain a normal stroke volume). The immature myocardium, however, is relatively ineffective in using these compensatory responses (28). The neonatal myocardium lacks mature sympathetic innervation as a result, in part, of a decrease in beta-receptor density. Further, compared with the adult myocardium, the neonatal left ventricular myocardium is poorly compliant and less able to enlist the Frank–Starling mechanism to preserve stroke volume. Finally, with severe coarctation in the newborn left ventricular pressure overload occurs rapidly, upon closure of the ductus arteriosus, without time for myocardial hypertrophy to develop. Left ventricular afterload and wall stress, therefore, increase in a relatively uncompensated fashion. It is clear that many factors make the immature myocardium particularly vulnerable to the hemodynamic disturbances imposed by severe coarctation, and explain the observation that ventricular systolic dysfunction and heart failure are confined primarily to the first weeks of life. Echocardiographic studies have demonstrated a decreased rate of early left ventricular diastolic relaxation, with consequent abnormalities in diastolic filling characterized by a shift of left ventricular filling into late diastole (29). These abnormalities in diastolic function are believed to relate to diminished left ventricular compliance caused by myocardial hypertrophy, myocardial fibrosis, and, possibly an increase in the inotropic state of the myocardium. An important functional consequence is an increase in left ventricular end-diastolic pressure at any given filling volume. Thus, left atrial hypertension and pulmonary venous congestion may occur, particularly in patients with an increased left ventricular end- diastolic volume. Prior to angioplasty (left panel) typical pressure contours are demonstrated: The systolic and pulse pressures are elevated in the ascending aorta and diminished in the descending aorta. After angioplasty (right panel) the pressure contours are normalized, with the peak systolic gradient decreasing from 50 mm Hg to 5 mm Hg. An associated congenital intracardiac defect compounds the hemodynamic burden in some patients with a coarctation. Valvar or subvalvar aortic stenosis will increase the left ventricular systolic P. A large ventricular septal defect, patent ductus arteriosus, or mitral regurgitation will increase left ventricular end-diastolic volume and ventricular preload. In concert with diminished left ventricular compliance, the augmented diastolic volume leads to an increase in left ventricular end-diastolic pressure. Subsequently, left atrial pressure will rise, and pulmonary venous and arterial hypertension may develop. Therefore, heart failure and pulmonary artery hypertension are relatively common in children with coarctation and associated aortic stenosis and/or ventricular septal defect as a consequence of disturbances in left ventricular preload, afterload, and diastolic function. Abnormalities in peripheral vascular physiology also occur in patients with coarctation. Systolic arterial hypertension is a manifestation of the coarctation stenosis, but it also reflects changes in vascular reactivity, arterial wall compliance, and baroreceptor function. Studies of patients after coarctation repair have demonstrated abnormal arterial vascular function (30,31,32), as well as resetting of the baroreceptor reflex in some patients with persistent hypertension (33). Such abnormalities in arterial physiology, which may be present after successful anatomic relief of coarctation, help to explain the occurrence of systolic hypertension in some patients many years after coarctation repair. Clinical Features The clinical presentation of coarctation generally follows one of three patterns: an infant with congestive heart failure, a child with a heart murmur, or a child or adolescent with systemic arterial hypertension. When coarctation presents in infancy, it often presents as a catastrophic illness. Congestive heart failure and shock can occur suddenly as the ductus arteriosus closes. A large proportion of these infants have coarctation with important associated structural lesions such as a ventricular septal defect or aortic stenosis. In an infant with severe coarctation and a large ventricular septal defect, the sudden onset of ventricular dysfunction, low cardiac output, shock, and acidosis classically develops around 8 to 10 days of life. Multiorgan system failure, particularly renal failure and/or necrotizing enterocolitis, and death occur rapidly unless definitive medical and surgical interventions are provided rapidly. Coarctation of the aorta may present later in childhood as systolic upper extremity hypertension or as a heart murmur. Delayed diagnosis beyond infancy is common as physical findings may be subtle, and most of these patients are asymptomatic. On careful investigation, some will report lower extremity claudication with exercise or frequent headaches. In a review of children (beyond infancy) presenting with coarctation at Columbia University between 1969 and 1978, the median age at diagnosis was 10 years. The correct diagnosis of coarctation was made by the referring physician in only 14% of cases (34). Physical Examination The general appearance of a child with coarctation will vary depending on the mode of presentation. In an infant with heart failure one encounters a pale, irritable child in respiratory distress. Tachycardia, dyspnea, diaphoresis, hepatomegaly, and poor perfusion signal the presence of congestive heart failure and low cardiac output. Differential cyanosis may be observed (cyanosis confined to the lower extremities) if a right-to-left ductal shunt is present. The characteristic findings of Turner syndrome are evident in some girls, and include short stature, widely spaced nipples, and a webbed neck.

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All left pulmonary arteries This is our procedure of choice for long-segment tracheal ste- were patent with a mean % fow by perfusion scan of 41 ± nosis purchase female cialis 20 mg with mastercard. If the carina is involved affecting Other large series that have reported improved results equally the takeoff of the right and left main stem bronchi 20mg female cialis with mastercard, a with the introduction of slide tracheoplasty for associated longitudinal incision should be made anteriorly in the distal tracheal stenosis include those from Melbourne safe 20mg female cialis, Australia33 segment of trachea with the incision extending to the inferior and Indianapolis. Before beginning the described 17 infants with congenital tracheal stenosis who anastomosis the left pulmonary artery is brought forward to underwent surgery between 1986 and 1996. Six patients its new location anterior to the trachea and is retracted with underwent resection and anastomosis and eight patients a silastic vessel loop while the anastomosis is performed. We concluded The posterior part of the anastomosis is performed frst as that short-segment (less than fve rings) tracheal stenosis is this is more diffcult. A continuous polydioxanone or Maxon best managed by resection and reanastomosis while longer- technique is used. The loops are not pulled tight until several segment tracheal stenosis can be managed by slide tracheo- bites have been taken so as to decrease the tension on each plasty or the castellation technique. Because the bites are in cartilage, however, consider- resection for very short-segment tracheal stenosis. The anastomosis is carried inferiorly around the carina and is completed on the right side of the mid-trachea. This Innominate artery compression of the trachea was frst is best achieved by suturing from the outside of the lumen. If the suture line is inverting it will result in an unaccept- described by Gross and Neuhauser from Children’s Hospital Boston in 1951. If the tracheal stenosis extends into one or other of the right or occurs at the level of the thoracic inlet because of a more dis- left main stem bronchi, the slide incisions can be performed tal than usual origin of the innominate artery. As the innomi- laterally such that the inferior incision extends onto the supe- nate artery passes rightward and superiorly it compresses the rior surface of the appropriate narrow bronchus. The trachea is lateral slide is considerably more easy to suture, it is not as usually malacic at this point over a distance of at least two effective for symmetrical enlargement of the carina as the to three rings. During respiratory infections the child may have an acute increase in stridor which may rEsults of surgEry be suffciently severe to cause the child to have apneic or Backer et al. At bronchoscopy there is characteristic pulsatile airway imaging with rigid bronchoscopy. Tracheal repair included pericardial patch nate artery compression of the trachea as frst described by tracheoplasty (n = 7), tracheal autograft (n = 10), tracheal Gross49 consists of an aortopexy procedure which lifts both Vascular Rings, Slings, and Tracheal Anomalies 661 the arch of the aorta as well as the innominate artery origin 9. A follow- a limited left anterolateral thoracotomy through the second up study of 11 unoperated cases. The roentgen diagnosis of double aortic arch between the great vessels and the trachea is probably helpful and other anomalies of the great vessels. Comparison and partial thickness in the aortic arch and origin of the innomi- usefulness of cardiac magnetic resonance versus computed nate artery similar to an aortic cannulation pursestring suture tomography in infants six months of age or younger with aor- in depth. The curved needles are straightened and are then tic arch anomalies without deep sedation or anesthesia. Am J passed through the second costal cartilage and leftward edge Cardiol 2011;108:120–5. When tied these sutures can pull the arch and stration of the ligamentum arteriosum in a case of right aor- innominate artery a considerable distance anteriorly and left- tic arch with aberrant left subclavian artery. Ann Otol Rhinol The child can be extubated either immediately following the Laryngol 1988;97:444–7. Invited letter concerning tracheal operations in usually a dramatic decrease in the amount of stridor though infancy. Surgical relief for tracheal obstruction from a vas- tinue to experience stridor and an exacerbation of symptoms cular ring. Video-assisted thoracoscopic division In fact, some have argued that the majority of patients with of a vascular ring in an infant: a new operative technique. Mayo Clin Proc Excellent long-term results have been described for 1993;68:1056–63. J pattern during pharyngeal arch artery remodelling is associ- Pediatr Surg 2009;44:1328–32. Anat Embryol (Berl) thoracoscopic division of vascular rings in pediatric patients. Anomalous origin of the anomalies causing tracheal and esophageal compression and left pulmonary artery from the right pulmonary artery. Circulation tracheal stenosis associated with anomalous left pulmonary 1981;63:458–60. Surgical man- Management of congenital tracheal stenosis by means of agement of pulmonary artery sling in children. J Thorac slide tracheoplasty or resection and reconstruction, with long- Cardiovasc Surg 2013;145:1033–9. Extracorporeal membrane oxygenation of color Doppler imaging misdiagnosis became unusual. They may artery is a rare lesion with an estimated incidence of between even exacerbate the problem. For infancy with some reports suggesting a mortality rate as example, pulmonary atresia with intact ventricular septum high as 90% in the frst year of life. False dropout often sug- pression of the right ventricle can be a fatal event for these gested normal aortic origin of the left coronary artery and babies. Transposition of the great arteries can be complicated there also could be misinterpretation of the transverse sinus by unusual coronary ostial distribution and branching pat- as the left main coronary artery leading to failure of early terns. At least 5% of patients with tetralogy of Fallot the management of neonatal coronary arteries make this an have an anomalous anterior descending coronary artery aris- eminently correctable lesion as long as surgery is performed ing from the right coronary artery. This chapter will focus on anomalies in which the coronary artery problem is the principal lesion. Interestingly, Embryology coronary anomalies are more common in females than males Normal development of the coronary arteries requires a unlike the majority of congenital cardiac anomalies that are connection between buds that arise from the aortic sinuses more common in males. The lous left coronary artery, albeit at a slightly reduced oxygen most common location is the leftward and posterior sinus of saturation. An anteriorly placed origin of the anomalous7 hyperplasia and hypertrophy of myocytes, as well as coronary coronary from the main pulmonary artery is exceedingly angiogenesis, are able to maintain appropriate wall stress as rare. Another rare variant that can be particularly diffcult to the left ventricle grows. With inadequate coronary perfusion, diagnose is origin from the right pulmonary but with fusion these things cannot happen, so the left ventricle becomes pro- of the left main coronary to the aorta just a few millimeters gressively dilated and thin-walled. Inspection by the by the relative dominance of the right and left coronary arter- surgeon will not allow diagnosis of this entity. In older patients, these vessels can become very through the anomalous coronary into the main pulmonary dilated. Under such circumstances, diagnosis becomes more artery arising anteriorly from the aorta, separate from the simple as color fow mapping or angiography demonstrates right coronary artery and giving rise to collateral vessels to fow into the pulmonary artery, and an oxygen step-up can the anomalous left coronary artery system. Such patients may be asymptomatic for several fbrosis and scarring of the left ventricle depending on the years, but as teenagers or young adults they may suffer from age of the patient, degree of dominance of the left coronary arrhythmias, angina, or sudden death. Endocardial7 fbroelastosis is prominent in some patients10 and the left ven- diAgnostic studiEs tricle is often very dilated, sometimes massively, unlike in patients with obstructive left heart problems who have endo- The young infant who is brought to the cardiologist with cardial fbroelastosis. Structural abnormalities of the electrocardiographic evidence of left ventricular ischemia mitral valve are unusual.

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Films are taken Magnetic resonance imaging in various projections so that all the loops of colon are unravelled discount female cialis 10 mg without a prescription. Magnetic resonance imaging of the colon is challenging Although diverticular disease and colonic carcinoma are due to movement artefacts from bowel peristalsis purchase 10mg female cialis mastercard. The technique is also used in patients who are frail and with poor mobility order discount female cialis line, in which case colonoscopy The radiological anatomy of the normal colon is shown in (and barium enema) would be diffcult to undertake. Haustra can usually be recognized in the whole of the colon, although they may be absent in the descending and sigmoid regions. Imaging signs of disease of the large intestine Narrowing of the lumen Narrowing of the colon may be due pathology: • inside the lumen of the bowel (e. Spasm is often seen in normal patients and, providing it is an isolated fnding, it can be ignored. Spasm is also seen in conjunction with diverticular disease and various infam- matory disorders. When attempting to diagnose the nature of a stricture in the colon the following points should be borne in mind: • Neoplastic strictures have shouldered edges, an irregular lumen and are rarely more than 6 cm in length (Fig. The calibre decreases from the caecum to • Diverticular disease the sigmoid colon. Filling of the terminal ileum and appendix with Gastrointestinal Tract 173 (a) (b) Fig. It is sometimes impossible to distinguish a stricture due to a carcinoma in Dilatation of the colon is diffcult to assess. Strictures due to diverticular disease are The causes of dilatation of the colon are: almost always confned to the sigmoid colon. Here the important consideration is not the strictures are usually centred somewhere between the dilatation itself but the nature of the obstructing lesion. Crohn’s disease and complete obstruction, colonoscopy and barium enema tuberculosis have a predilection for the caecum. Extrinsic compression causing a smooth indenta- water-soluble contrast enema is occasionally undertaken tion on the caecum may be seen with a mucocele of the when it proves diffcult to distinguish paralytic ileus appendix, appendix abscess or an infammatory mass in (also called ‘pseudo-obstruction’) from mechanical obstruc- Crohn’s disease. The contrast study will show a 174 Chapter 6 dilated, but otherwise normal, colon in the case of paralytic ileus. Faeces cause a flling defect which can be very dif- fcult to distinguish from a polyp or tumour (Fig. Therefore, whenever possible, all imaging examinations of the colon should be made with a clean colon in order to avoid misdiagnosing polyps that are in fact faeces. Faeces have no attachment to the wall of the bowel, are completely surrounded by barium or air, and move according to the position of the patient, usually lying in the dependent part of the bowel. Intramural haemorrhage, oedema or air in the wall of the colon (pneumatosis coli) all cause multiple, smooth flling defects arising from the wall of the bowel. Lumps of faeces have caused smooth Ulceration flling defects surrounded by barium. However, in the sigmoid colon there is a large flling defect with ill-defned edges (arrow); Ulcers of the colonic mucosa can be recognized on barium this is a carcinoma. A clean colon is essential for a satisfactory enema as small projections from the lumen into the wall of barium enema. The two major causes of ulceration are ulcerative colitis and tinguish between the two conditions (which, therefore, are Crohn’s disease. Rarer causes include tuberculosis and often both referred to as infammatory bowel disease). Imaging can be important not only for diagnosis, but also to assess the extent and severity of the disease and to detect Specifc diseases of the colon complications. Infammatory bowel disease Ulcerative colitis Although classic changes are described for both ulcerative Ulcerative colitis is a disease of unknown aetiology charac- colitis and Crohn’s disease, it is sometimes diffcult to dis- terized by infammation and ulceration of the colon. When more extensive Strictures are rare, and, when present, are likely to be due it extends in continuity around the colon, sometimes affect- to carcinoma; the incidence of colonic carcinoma in long- ing the whole colon. The ulcers are usually shallow, but in severe in continuity from the rectum to the proximal extent of cases may be quite deep. In chronic ulcera- is loss of the normal colonic haustra in the affected portions tive colitis there is visible fatty infltration in the submu- of the colon. Oedema of the perirectal tissues causes widen- cosa, resulting in a ‘target sign’ appearance (Fig. When the whole colon is involved, the terminal ileum Narrowing and shortening of the colon, giving the appear- may become dilated. The diagnosis is made on clinical grounds these islands of infamed mucosa makes it diffcult to assess and on examination of the plain abdominal flm or stand- the true depth of the ulceration. In this case of ulcerative colitis, the ulceration causes the normally smooth outline of the colon (a) (b) to be irregular. With longstanding disease, the haustra are lost and the colon becomes narrowed and shortened, coming to resemble a rigid tube. The transverse and descending colon are thick-walled and infamed with enhancement of the mucosa and marked dilatation of the lumen. The colon may be the only part of the alimentary tract to be involved, but usually the disease affects the small bowel if the colon is involved. At an early stage in the disease, the fndings at barium enema are loss of haustration, narrowing of the lumen of the bowel and shallow ulceration. This criss-crossing ulcer- ation combined with mucosal oedema may give rise to a ‘cobblestone’ appearance of the mucosa (Fig. The ulcers may be very deep, penetrating into the muscle layer, when they are described as ‘rose-thorn ulcers’ or deep fssures. The deep ulceration in Crohn’s disease may lead to the formation of intra- and extramural abscesses. The disease is not always circumferential; one of the features that distinguish it from ulcerative colitis is that it may involve only one portion of the circumference of the bowel. Another important diagnostic feature is the presence of the so-called ‘skip lesion’ (Fig. Skip lesions are virtually ‘cobblestone’ appearance due to criss-crossing fne ulceration. However, the entire colon may be involved or the disease may be limited to just one Diverticular disease segment. The rectum is often spared – another important Diverticula are sac-like out-pouchings of mucosa through differentiating feature from ulcerative colitis. Very deep ulcers are present; two examples of an ulcer tracking in the submucosa are arrowed. A long stricture is present in the transverse colon (between the curved arrows) and a shorter one in the sigmoid colon (between the small arrows).

The autonomic nervous system plays a vital role in regulating the spontaneous depolarization rate of the sinus node and thus the overall heart rate as the sinus node is typically the area of the heart with the most rapid spontaneous depolarization and therefore typically serves as the intrinsic cardiac “pacemaker cheapest female cialis. Absolute minimums for sinus bradycardia for the pediatric population have not been established firmly and some patients with very slow heart rates are completely asymptomatic and will never have any clinical ramifications from their bradycardia order 10mg female cialis with amex. The definition of sinus bradycardia is a rhythm that originates in the sinoatrial node and is less than the lower rate value for age (Fig buy discount female cialis 10 mg. The sinus node is not a pinpoint structure, but rather is a crescent-shaped series of cells that may extend inferiorly to near the orifice of the inferior vena cava. Different areas of the sinus node may serve as the dominant pacemaker occasionally resulting in a slight shift in the P-wave axis to a focus in the low right atrium. Sinus bradycardia is, in general, a benign entity that often occurs in athletes or during rest/sleep. Each person has his or her own set heart rate, and rates below “normal” values may be seen but may be completely normal and physiologically appropriate for an otherwise asymptomatic individual. Because of the general lack of symptoms, the true incidence of sinus bradycardia in the pediatric population is unknown. In a study performed on highly trained junior athletes, many subjects were found to have marked sinus bradycardia at rest, and this finding should be considered normal in individuals who are athletically fit (113). Although the majority of patients with sinus bradycardia are asymptomatic, some may have symptoms of fatigue, syncope, exercise intolerance, sleepiness, and/or nightmares and these findings should prompt evaluation for underlying causes of the bradycardia (114). Common causes of sinus bradycardia include physical conditioning, anorexia, medications, or acute infections. Periods of abrupt sinus bradycardia and/or sinus arrest can occur in breath-holding spells or vasovagal/autonomic-mediated syncope. After a diagnosis of sinus bradycardia is made, a thorough history and review of symptoms is warranted to attempt to rule out a pathologic cause. Reversible causes of sinus bradycardia include such disorders as Cushing triad (acute increase in intracranial pressure, hypertension, and irregular respiration), hyperkalemia, hypercalcemia, hypoxia, hypothyroidism, hypothermia, and ingestions of such substances as beta-blockers, lithium, and digitalis (115). Rarely, cases of sinus bradycardia also may signify another disease such as myocarditis, diphtheria, or rheumatic fever (116). If additional testing is necessary to evaluate sinus bradycardia, other noninvasive tests such as a Holter monitor, an event monitor, or a 30-day loop recorder may be indicated. If these tests are not helpful or worry persists, the exercise stress test is another noninvasive test that can help rule out a pathologic sinus bradycardia. The exercise stress test can be performed on cooperative children as young as 4 to 5 years old. This test is designed to give precise measurements of heart rate in response to an increasing load. The goal of exercise testing in a child with sinus bradycardia is to determine their maximal heart rate and response of the sinus node to exercise. The vast majority of patients who have an exercise test as an evaluation for sinus bradycardia achieves a normal peak heart rate and therefore needs no further workup. Treatment The only reason to treat patients with sinus bradycardia is when symptoms of fatigue or syncope are temporally correlated with the presence of a slow heart rate on multiple occasions and there is no other underlying cause for the bradycardia. Routine sinus bradycardia in the absence of any underlying symptoms does not require treatment. Severe cases of autonomic dysfunction or breath-holding spells with frequent sinus pauses resulting in syncope may benefit from pacemaker placement, but this almost never is necessary, particularly in young children for whom the symptoms frequently will resolve by age 4 to 6. In addition, there is frequently a blood pressure drop in older patients that may result in continued symptoms and syncope despite an adequate heart rate. If the patient has an appropriate atrial or junctional escape rhythm that increases with exercise, they may be completely asymptomatic. Those who experience symptoms may have only subtle signs of fatigue, inability to keep up with their peers, shortness of breath, syncope, or more marked symptoms of heart failure or syncope. It is seen following surgery for congenital heart defects particularly those involving multiple atrial surgeries possibly from disruption of the sinus node artery during the repair or during placement of the superior vena cava cannula for cardiopulmonary bypass (120,121,122). In addition, reversible causes include hypothyroidism, increased vagal tone, hypothermia, and medications. If clinically indicated, laboratory evaluation including a drug screen, thyroid function tests and evaluation for rheumatic disorders, infections, or metabolic causes may be performed. This recommendation also includes those patients with chronotropic incompetence as a result of required drug therapy. The cause of impaired impulse transmission may be directly related to structural cardiac disease, trauma, myocardial infarction or inflammation (such as in myocarditis), or abnormal impulse propagation from an underlying cardiac channelopathy. The block can also result from enhanced vagal tone, surgery for congenital heart disease, or infections such as Lyme disease or Chagas disease (124). Generally, the finding is normal, with a prevalence of up to 8% of normal children (126). In most cases, it is due to increased vagal tone and will resolve when sympathetic tone increases. Wenckebach is generally transient in nature and caused by increased vagal influence. The majority of episodes of Wenckebach occur in healthy, asymptomatic patients during sleep or other times of high resting vagal tone. Wenckebach typically does not occur while awake except in rare incidences in highly trained professional athletes. Wenckebach during exercise or at times of increased catecholamine state is pathologic and should be thoroughly evaluated for the presence of conduction system disease. If Wenckebach is thought to be physiologic (particularly during sleep), no therapy is required and follow-up is unnecessary. This type of block is never seen as a normal variant and should always be considered pathologic. This rare conduction abnormality generally, but not always, represents a conduction defect encountered below the bundle of His (130). The most common reason for this problem in the pediatric population is myocarditis or a postsurgical complication. This finding is typically benign and related to an increased vagal tone or resting state. Differentiation also can be performed using an intracardiac tracing by looking for the presence of a bundle of His recording following the atrial depolarization. Additional cardiovascular malformations (tetralogy of Fallot, atrial septal defects, transposition of the great vessels, and tricuspid atresia) have been described, without any apparent association between the structural abnormality and the conduction defect. The specific mechanism of damage to the conduction system occurs when maternal antibodies cross the placenta and react with their corresponding antigens expressed on the surface of cells of the fetal cardiac conduction system, resulting in immunoglobulin deposition on the cells of the fetal conduction system and on the cardiac myocytes. This local inflammatory reaction leads to permanent damage to the fetal cardiac conduction system because of localized cellular apoptosis (156,157,158,159,160). Patients with antinuclear antibodies may have a higher incidence of long-term development of heart failure and death compared to those who are antibody negative (161).

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Under normal fow conditions discount female cialis 20mg overnight delivery, the shear reduced female cialis 20mg generic, blood will be at its most viscous buy 20mg female cialis overnight delivery. The complex- rates are relatively high in both pre- and postcapillary seg- ity of determining the viscosity of blood is complicated by ments. However, at low fow rates the lower shear rate in the the deformability of the cells which circulate within it and postcapillary segment (with corresponding higher viscosity) involves application of the principles of rheology defned results in an increase in the post- to precapillary resistance as the study of the fow of matter, including complex sus- ratio with a resulting increase in capillary pressure. The behavior of a fuid containing a suspension could play a regulatory role in transcapillary fuid exchange of rigid particles which are nondeformable is more easily and may be relevant to the accumulation of tissue fuid during predictable. Thus, a red Viscosity Effects of Hemodilution cell has a smaller effective particle volume as it aligns with An exponential relationship exists between hematocrit and the direction of fow. Variation in imposed shear of a decrease in apparent viscosity of blood with increas- rate infuences this relationship and at lower shear rates more ing shear. Increased shear per se can result in disaggrega- the magnitude of change in viscosity with change in shear rate tion of rouleaux and results in an increase in effective cell observed at lower hematocrits suggesting that blood becomes concentration. Shear stress can be transmitted into the inte- more Newtonian in its fow characteristics when dilute. This property results in a further reduction in Hemodilution, Cardiac Output, the viscous resistance of blood, particularly when passing and Peripheral Resistance through a capillary. The associated intracellular fow can Cardiac output is determined by perfusion pressure and total supplement oxygen release via intracellular transport of oxy- peripheral resistance. The deformability of red cells is a function of a variety of factors, including imposed shear 4 k( − )r stress, cellular structure, and surface area, membrane visco- q = 8ηl elastic properties and intracellular viscosity. Because of the exponential relationship between hemato- crit and blood viscosity, changes in hematocrit are associated with disproportionate changes in viscosity. This relationship, in combination with the linear relationship of oxygen content to hematocrit, results in maximal oxygen-carrying capacity at a hematocrit below normal in the intact animal which increases cardiac output in response to hemodilution. The pharmacology of dextran and the physiological background for the clinical use of Rheomacrodex and Macrodex. Crystal and Salem31 reported that ited by the fact that it applies specifcally for laminar fow although regional blood fow was increased in several organ of Newtonian fuids in vessels with rigid walls. However, the beds following hemodilution, blood fow was unchanged in relationship draws attention to the important inverse relation- the spleen and kidney resulting in a net reduction in oxygen ship between fow and viscosity. These results clearly have important vessels provide little impedance to blood fow while most of implications for the survival of the kidney during cardio- the vascular resistance comes from smaller vessels. As vessel pulmonary bypass when there is no compensatory increase diameter decreases shear rate decreases and since blood vis- in fow rate. As noted above, fow is lowest and viscosity highest in does not call for any increase in perfusion fow rate to com- the postcapillary venules. Thus, hemodilution is associated with an increase in cardiac out- the most obvious effect of hemodilution is a marked decrease put. The increase is inversely proportional to hematocrit28 in perfusion pressure at the initiation of bypass. This suggested that a fur- in cerebral blood fow to ischemic areas of the brain follow- ther decrease in hematocrit at normothermia would not be ing hemodilution. The third possible expla- 20 nation suggests that endothelial cells may sense varying lev- 0 els of shear stress. Thus, decreasing viscosity associated with hemodi- lution would be expected to lead to arterial constriction. All groups underwent 60 minutes series of patients on cardiopulmonary bypass at constant fow rates. Changes in of deep hypothermic circulatory arrest at 15°C with continu- arterial pressure, viscosity and resistance during cardiopulmonary ous magnetic resonance spectroscopy to measure cerebral bypass. Behavioral as those in many similar reports did not eliminate increased recovery was evaluated for 4 days by a veterinarian who was cardiac output as a possible cause for the increased cerebral blinded to treatment assignment. Increased cardiac out- assessed after sacrifce on day 4 by an experienced neuropa- put has been suggested by others studying a variety of other thologist who also was blinded to treatment assignment. Using Doppler examinations of the carotid arter- the cooling phase even before any circulatory arrest. There ies of newborn baboons, Raju and Kim34 demonstrated that was loss of phosphocreatine (Fig. It was concluded that extreme nation is based on Poiseuille’s model of steady state fow. Higher hematocrit improves cerebral outcome after deep hypothermic circulatory arrest. Functional agammaglobulinemia, which may quate oxygen delivery during early cooling and that the higher persist for over 20 hours, has been described following hemo- hematocrit achieved with a blood prime is associated with dilution with dextran-60. In addition to simple hemodilution of immunoglobulins, it has been suggested that some of the colloidal agents used in the pump prime can reduce complement activation. The fall in plasma colloid oncotic during CardioPulmonary ByPass pressure that results from hemodilution plays an important Prime Volume role in the extracellular fuid accumulation that is observed The total priming volume is determined by the hardware following cardiopulmonary bypass. Tissue edema is in part selected for the circuit to be employed (see Chapter 8, The secondary to the increased capillary permeability which is a manifestation of the systemic infammatory response Bypass Circuit: Hardware Options). It can be further exac- prime volume, a smaller oxygenator should be selected that erbated by even a slight increase in venous pressure, e. An than selecting a large oxygenator that will function toward accompanying fall in colloid oncotic pressure worsens the it lower level. This appears to be more important in neonates the control of the surgical and perfusion team is the diam- who have a naturally higher capillary and venule permea- eter and length of tubing. Electron microscopy demonstrated greater a greater safety margin for brief periods of inattention by myocardial edema in the puppy group. Although there were the perfusionist, nevertheless a price is paid in terms of the no changes in percentage wet weight ratios in either group, total perfusate volume to which the patient will be exposed. Other studies have suggested there may coupled with fow cutoff switches allow a greater level of be a difference in infammatory response including changes confdence in running very low reservoir levels. The surgical in blood–brain barrier permeability between premature and assistants can also be helpful in returning blood promptly to full-term neonates. Coagulation Factors Use of any priming solution other than whole blood (including Homologous (Banked) Blood Required for Priming packed cells) results in a reduced concentration of all coagu- A decision must be made initially regarding the desired hema- lation factors, as well as active platelets. This is a complex bypass also activates the fbrinolytic system so that there is decision that is discussed below (see Optimal Hematocrit for an important risk of increased bleeding not only because of Cardiopulmonary Bypass). When the desired hematocrit has reduced fbrin formation, but also because of increased fbrin been selected, the amount of bank blood that must be added breakdown. The current fgure that is available from the If it is necessary to add blood to the prime, it should be Red Cross of America regarding the risk of viral transmis- as fresh as possible. Ideally, the blood used for a neonate or sion from a single unit of blood is 1 in 750,000. This is an infant should be less than 72 hours old, although current test- exceedingly small risk relative to many of the surgical risks ing for viruses can impose important practical imitations. Nevertheless, it is not uncommon Therefore, the practice at many centers including Children’s for families to insist upon directed blood donations and most National Medical Center is to insist upon banked blood that hospital blood banks including our own offer a “directed is less than 1 week old for priming the pump. Interestingly, this has not been shown to of blood are reserved for transfusion following bypass.

The patient was started on cabergoline and subse- quently cheap female cialis 10 mg overnight delivery, prolactin levels normalized with regression of acromegaloid features purchase female cialis us. The clinical profile of the index patient is strongly suggestive of hyperprolac- tinemia order female cialis 20mg visa. However, normal serum prolactin on multiple occasions suggest the possibility of “hook effect”. Her repeat serum prolactin in dilution (1:100) was 800 ng/ml, confirming the presence of “hook effect” in this patient. A 25-year-old female was incidentally found to have high prolactin level of 100 ng/ml. The circulating prolactin is predominantly (85%) monomeric and has a molecular weight of about 23 Kd. But, in certain individuals, prolactin exists as multimers forming big prolactin (48 Kd) or big-big prolactin (100 Kd). These prolactin multimers, prolactin–IgG complex, and prolactin–anti-prolactin anti- body complex constitute macroprolactin which has a molecular weight of >150 Kd. Macroprolactin interferes with prolactin assay and results in fallaciously high prolactin value. In the index case, estimation of prolactin by polyethylene glycol precipitation method revealed macroprolactinemia. As drugs are the most common cause of mild hyperprolactinemia, a detailed history for ingestion of related drugs was sought, but it was noncontributory in the index patient. She was advised lifestyle modification, following which she lost 5 kg weight and resumed her cycles. A 30-year-old woman has persistent amenorrhea despite normalization of thyroid function after optimal levothyroxine treatment for primary hypo- thyroidism. After normalization of thyroid function with optimal levothyroxine treatment, majority of women with primary hypothyroidism resume their menstrual cycles within 3–6 months. Other possibilities include hyperprolactinemia due to residual thyro-lactotrope hyperplasia and secondary polycystic ovarian disease. Prolactinomas are usually associated with a serum prolactin >100 ng/ml and a level >250 ng/ml is virtually diagnostic of prolactinoma. Hence, in patients with serum prolactin <100 ng/ml despite the presence of microadenoma, other causes of hyperprolactinemia should be sought. Therefore, the diagnosis of drug-induced hyperprolactinemia with non-functioning pituitary microade- noma was made. The index patient had oligomenorrhea and galactorrhea with elevated serum prolactin for which she was started on cabergoline but had suboptimal response. In any patient with mild hyperprolactinemia (<100 ng/ml), a thorough drug history must be elicited. Treatment of drug-induced hyperpro- lactinemia includes discontinuation of the offending drug if possible, substitu- tion with alternative antipsychotics which does not cause hyperprolactinemia (aripiprazole or quetiapine), or use of oral contraceptive to relieve hypogo- nadal symptoms. This may normalize serum prolactin in approximately 75% of patients but has a risk of worsening of underlying psychosis and hence is not recommended. A 34-year-old female on anti-psychiatric drugs presented with oligomen- orrhea and galactorrhea. In symptomatic patients of hyperprolactinemia, where withdrawal of incrimi- nating drug is not possible and there is a probability of worsening of underlying disorder with the use of dopamine type 2 receptor agonists, gonadal steroids may be used to relieve the symptoms of hypogonadism. The other option after appropriate consultation with psychiatrist is to switch to atypical anti-psychotic drugs like quetiapine which has low antidopaminergic effect or change to anti- psychotic drugs having dopamine agonist and antagonist activity like aripipra- zole, to minimize the effect on serum prolactin levels without worsening of disease. Is treatment necessary in asymptomatic patients with drug-induced hyperprolactinemia? There is no need to treat asymptomatic patients with drug-induced hyperprolac- tinemia. Patients should be carefully evaluated for symptoms of hypogonadism, especially in men. Prolactinoma is the most common pituitary tumor and contributes to 40–45% of all pituitary tumors. This is followed by somatotropinoma (15%), mamoso- matotropinoma (3–5%), corticotropinoma (10%), and thyrotropinoma (1%). Clinically non-functioning pituitary tumors contributes to the rest and include gonadotropinoma (15%) and null cell adenoma (5–10%). Women usually present with menstrual irregularities, galactorrhea, and infertility and hence are detected earlier and commonly have microade- noma. On the contrary, men present with symptoms of mass effects in addi- tion to features of hypogonadism and usually harbor macroadenoma. This probably reflects a delay in diagnosis because of nonspecific symptoms in men, which allows more time for tumoral growth. In addition, high tumor proliferative indices might contribute to the occurrence of macroadenoma in men. Majority of prolactinomas are microadenomas (<10 mm) and occur more often in women, while macroprolactinomas (>10 mm) are more common in men. Patients with familial prolactinomas usually present at a younger age, have invasive adeno- mas, and are resistant to therapy. Malignant prolactinoma should be suspected in the presence of atypical clinical manifestation (e. However, the pres- ence of distant metastasis is the only definitive evidence of malignant prolacti- noma. Malignant prolactinoma has a male preponderance (2:1) and the mean age of presentation is 44 years. Seventy-five percent of patients have intracra- nial metastasis, while extracranial metastasis to spinal cord, bone liver, and 3 Hyperprolactinemia 51 lymph node is present in 40% of patients. Treatment options include surgery, high-dose cabergoline, temozolomide, and local radiotherapy. Medical management is highly rewarding in patients with prolactinoma than in any other pituitary tumors. In addition, there is always a possibility of recovery of residual pituitary func- tion and drug discontinuation after optimal medical therapy. The ergot deriva- tives include bromocriptine, cabergoline, pergolide, and lisuride, while the non- ergot derivative includes quinagolide. Clinical scenario Treatment Asymptomatic Reassurance Desire for fertility D2 receptor agonist Troublesome galactorrhea D2 receptor agonist Family completed but wishes regular D 2 receptor agonist or oral contraceptive pills cycles Concern for bone health (in women) D2 receptor agonist or oral contraceptive pills Postmenopausal No treatment/bisphosphonates for bone health Men with hypogonadism and/or D 2 receptor agonist osteoporosis 37. The efficacy of medical treatment in terms of a composite endpoint including normalization of serum prolactin, restoration of gonadal function, and reduc- tion in tumor size are listed in the table given below. Is the risk of valvulopathy associated with D2 receptor agonist therapy real in patients with prolactinoma? Patients with Parkinson’s disease who are treated with caber- goline and pergolide have an increased risk of valvulopathy.

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