The combined use of acupuncture with anesthetics in the renal transplantation markedly reduced the consumption amounts of anesthetics discount zenegra master card, which improved the recovery of the transplanted renal functions and avoided complication in the Shanghai First People’s Hospital (Qu et al discount zenegra 100mg on-line. It was found that the anesthetic effect in patients under acupuncture-balanced anesthesia was comparable with that under epidural block purchase zenegra on line. The average amount of anesthetics used in patients under acupuncture-balanced anesthesia was only about half of that used in patients under epidural block cheap generic zenegra uk. Furthermore, in patients under acupuncture-balanced anesthesia, the blood pressure and heart rate were observed to be stable during the operation, 149 Acupuncture Therapy of Neurological Diseases: A Neurobiological View without the need for the hypertensor; however, the blood pressure in patients under epidural block often fluctuated. Also, the start time of urination of the transplanted kidney in patients under acupuncture-balanced anesthesia was significantly reduced when compared with that in patients under epidural block. Although the surgical operations under acupuncture anesthesia are limited, different kinds of acupuncture treatment have been used during or after surgical operations. A prospective randomized double-blind controlled test was carried out in Milan, Italy. The three groups were: Group A no acupuncture; Group B true acupuncture, started 20 min before surgery; and Group C sham acupuncture, started 20 min before surgery. A total of 25 patients scheduled for inpatient phacoemulsification were enrolled in each group. The results showed that acupuncture was effective in reducing anxiety related to cataract surgery under topical anesthesia. Using a controlled and double-blind study carried out in Japan, the hypothesis that preoperative insertion of intradermal needles at acupoints 2. Before anesthesia, the patients scheduled for elective upper and lower abdominal operations were randomly assigned to one of the two groups: acupuncture (n 50 and n 39 for upper and lower abdominal surgery, respectively) or control (n 48 and n 38 for upper and lower abdominal surgery, respectively). Postoperative analgesia was maintained with epidural 150 6 Acupuncture-Drug Balanced Anesthesia morphine and bolus doses of intravenous morphine. Commencing from the recovery room, the intradermal acupuncture produced good pain relief when compared with the control (p<0. The consumption of supplemental intravenous morphine was reduced to 50%, and the incidence of postoperative nausea was reduced to 20% 30% in the acupuncture group (p<0. Plasma cortisol and epinephrine concentrations were reduced to about 30% 50% in this group during recovery as well as on the first postoperative day (p<0. The authors suggested that reoperative insertion of intradermal needles could reduce postoperative pain, analgesic requirement, and opioid-related side-effects after both upper and lower abdominal surgery. Acupuncture analgesia is also observed to reduce the activation of the sympathoadrenal system that normally accompanies surgery. The pain-relieving effects of the implantation of gold beads into dogs with hip dysplasia was investigated with double-blind, placebo-controlled trial in Norway (Jaeger et al. Seventy-eight dogs were randomly assigned to two groups, 36 in the gold implantation group and 42 in the placebo group. Both groups were treated equally regarding anesthesia, hair clipping and penetration of the skin with the same type of needle. The gold implantation group had small pieces of 24 carat gold inserted through needles at five different acupuncture points and the placebo group had the skin penetrated at five non-acupuncture points so as to avoid any possible effect of stimulating the acupuncture points. After 14 days, three months and six months, the owners assessed the overall effect of the treatments by answering a questionnaire, and the same veterinarian examined and evaluated each dog. There were significantly greater improvements in mobility and greater reductions in the signs of pain in the dogs treated with gold implantation than in the placebo group. A study of the application of acupuncture analgesia in cranio-maxillofacial surgical procedures was reported in Belarus (Pohodenko 2005). In 20 of these, surgery was carried out under general anesthesia in combination with acupuncture analgesia. In 100 patients, acupuncture analgesia was applied in addition to traditional postoperative analgesia. In case of troublesome postoperative pain, it was necessary to carry out additional sessions of acupuncture stimulation. When acupuncture analgesia was used, the pulse rate and blood pressure during surgery generally remained stable, and the serum cortisol was only showed minor elevation. The author suggested that acupuncture analgesia can be a useful adjunct to conventional anesthesia in maxillofacial surgery. A study was reported in which a simple acupuncture procedure was used in patients under standard intravenous anesthesia in the Chang Gung Memorial Hospital, Taipei, China (Shyr et al. About 10 out of the 32 control patients experienced nausea or vomiting, when compared with only 2 out of 32 patients receiving acupoint injection, and the reduction in nausea was significant. Hence, it is recommended that the use of acupuncture as an antiemetic should be explored further. Another similar study was carried out in Northern Ireland based on the abovementioned test (Dundee and Ghaly 1991). The incidence of postoperative illness was monitored for 6 h in 74 women premedicated with nalbuphine, 10 mg, who were undergoing short gynecologic operations of similar duration under methohexital nitrous oxide-oxygen anesthesia. In a random order, the site of the acupuncture was previously infiltrated with normal saline solution in half of the patients, and 1% lidocaine in the remaining patients. Postoperative emetic sequel occurred significantly more often in those who received lidocaine, when compared with the group that received saline solution. Lee and Done (2004) searched database about stimulation of the wrist acupuncture point P6 for preventing postoperative nausea and vomiting. Regularly rated pain intensity (five-point verbal rating scale), consumption of 500-mg tablets of acetaminophen, and additional rescue medication with 500 mg of mefenamic acid, were assessed. The healthy volunteers were anesthetized with desflurane, and noxious electrical stimuli were administered via 25-gauge needles on both the thighs (70 mA at 100 Hz for 10 s). Hence, the combination of acupuncture with a reduced dose of anesthetics (dolantin) may be advisable. It is well known that epidural morphine is commonly used in the clinic to relieve postoperative pain; however, it is observed to induce immunosuppression, inhibition of the intestinal peristalsis, and respiratory inhibitions. Note that the morphine induced inhibition of the intestinal peristalsis was significantly reduced. These drugs were classified into three main categories according to their effect on acupuncture analgesia: drugs with potentiating effect; drugs with reducing effect; and drugs without significant influence. This classification may provide the clinical principles for the medical doctors to select the proper adjuvant according to different conditions. Subsequently, the mechanism of some drugs affecting acupuncture analgesia was investigated using multidisciplinary techniques by our experiment research group (Zhu et al. This suggests that further activation of the opioid receptors might underlie the mechanisms of the drugs’ potentiating effect on acupuncture analgesia (Fig. In the autoradiographic images, the red color indicates higher density of the opioid receptors, while the blue indicates lower density. In situ hybridization was performed on the brain slices from the rats sacrificed 10 h after Dro (1. On the other hand, the analgesic effects could also be found in some biologically active substances, such as melatonin (Yu et al. In the Beijing Tiantan Hospital and Shanghai Huashan Hospital of Fudan University, the acupoint stimulation was used to combine the modern awake anesthesia in craniotomy. Furthermore, in the Renji Hospital affiliated to the Shanghai Second Medical University (now affiliated to Shanghai Jiaotong University), the cardiac surgery was performed with acupuncture-drug balanced anesthesia. In 2007, the research project of acupuncture anesthesia won funds from the National Key Basic Research Program in China. We are confident that the research of acupuncture-drug balanced anesthesia which was initiated in China will continue to make great progresses and improve its application at the bedside, bringing more and more benefits to the patients. Acknowledgements This work was supported by the grants from the National Key Basic Research Program (No. Acupunct Electrother Res 27: 1 14 Chen Y, Chen X, Chen P, Li L, Jian L, Chen Y (1990) Maintenance of best needle sensation and small dose of fentanyl and droperidol applied in herniotomy. Chin Med J 106: 220 224 Department of Physiology, Shanghai First Medical College, Shanghai First Tuberculosis Hospital and Shanghai Institute of Acupuncture and Moxibustion (1973) Effect of acupuncture of points on the pain threshold of normal human subjects. In: Group of Acupuncture Anesthesia (ed) Selection of Research on Acupuncture Anesthesia, Shanghai People’ Press, Shanghai. Clin Pharmacol Ther 50: 78 80 Gioia L, Cabrini L, Gemma M, Fiori R, Fasce F, Bolognesi G, Spinelli A, Beretta L (2006) Sedative effect of acupuncture during cataract surgery: Prospective randomized double blind study.
A Pathology curved hook is passed beyond the foreign body which is then gently pulled forward effective 100mg zenegra. A A foreign body retained in the nose produces eustachian catheter usually serves this an inflammatory reaction and stagnation discount zenegra 100 mg without a prescription. When the patient is uncooperative leads to the formation of granulation tissue and the foreign body is impacted or deeply and ulceration buy 100 mg zenegra. Animate Foreign Bodies Diagnosis Animate foreign bodies include maggots cheap zenegra amex, The history is suggestive but many a time leeches and other insects. In removed by putting pinch of salt, or hyper- Foreign Bodies in the Nose 179 removed with a forceps as maggots crawl out for want of oxygen. Rhinolith Concretion formation in the nose results if a foreign body gets burried in granulations and remains neglected. This forms a nucleus around which a coating of calcium and mag- nesium phosphate and carbonate occurs and thus a rhinolith forms. Sometimes inspissated mucopus or a blood clot may be a nidus around which such a change takes place. It is surgically removed under tonic saline or a few drops of oxalic acid on general anaesthesia. Sometimes a large rhinolith may a ribbon gauze pack soaked in terpentine oil, necessitate a lateral rhinotomy procedure for kept in the nasal cavity for some time and then its removal. Little’s Area The anteroinferior part of the septum is the most common site of bleeding in majority of the cases. Branches from the anterior ethmoid, Factors like coughing, sneezing, straining sphenopalatine, greater palatine and superior and blowing play a contributory role by labial arteries take part in this anastomosis causing rise in the vascular pressure. There is a venous plexus near the poste- Aetiology rior end of the inferior turbinate called The main causes of epistaxis are grouped as Woodruff’s area, which is another common site under: of bleeding in the nose. Trauma: External trauma to the nose and repeated ulceration may be the cause of (accidental), repeated nose picking the nose bleed. Fungal infection Management • Rhinosporidiosis General assessment of the patient’s condition • Blastomycosis is essential. The pulse and blood pressure are • Coccidiomycosis monitored and resuscitative measures like c. Congenital during a bleed, he is asked to clean the nose Telangiectasia (Osler-Weber-Rendu which is then pinched for about 10 minutes. The area is anaesthetised by local nasal sinuses xylocaine pack and cauterisation done. Exanthematous fevers like measles, Nasal packing Every attempt should be made mumps, typhoid to control the bleeding without packing the g. Hodgkin’s disease nose, as this causes further trauma to the nasal 182 Textbook of Ear, Nose and Throat Diseases mucosa, is troublesome for the patient, and nose is packed, as packing disturbs the nasal delays recovery. Various packing is needed when bleeding is haemostatic preparations like adenochrome, profuse and does not stop on pinching the vitamin C and K, and calcium preparations nose. A lubricated or medicated gauze is play only an adjuvant role in stopping the used for this purpose although nowadays bleeding. Packing Alternatively, nasal packing may be should never be done with a dry gauze. In such cases ligation continuous in spite of proper anterior nasal of the blood vessels supplying the nose may packing, then posterior nasal pack may be be the only alternative. This can be done under general The nose is mostly supplied by the external or local anaesthesia supplemented by carotid artery through its sphenopalatine sedation. The threads of artery in the neck or the internal maxillary the pack are attached to the ends of the artery in the sphenopalatine fossa arrests catheters which are then withdrawn into bleeding. The pack is guided by fingers from the area supplied by the anterior ethmoid behind the soft palate. The ligation of ethmoid vessels is done rubber catheter are tied on a rubber piece through a periorbital incision in the medial at the columella. A separate thread attached to the Besides these measures of controlling gauze pack is brought out through the bleeding from the nose, attention should be mouth. Racial: The deflections are more common in Europeans than in Asian or African Deviations of the nasal septum are commonly races. Age: Deflections are uncommon in anatomical, physiological and pathological children. Hereditary: Heredity may be a factor in its Various theories and factors have been put causation. High arched palate: Lack of descent or broadening of the palate as occurs normally during infancy may be a factor. Injury ruptures the chondro- osseous joint capsule of the septum and causes dislocations and fracture of the premaxillary wings. Birth moulding theory: Prolonged and forceful stress during the birth process affects the nose and causes dislocations and deformations. Cosmetic deformity: The dislocated ante- The deviated septum, depending on its loca- rior end may project out into the nasal tion and degree, is the most common cause of vestibule or cause deformity of the tip. Pain due to pressure on the anterior breathing with consequent dryness of the ethmoidal nerve. These predispose An external nasal deformity affecting the to recurrent attacks of sore throat, common cartilaginous part of the nose may be present. Impairment of The anterior end of the cartilaginous septum drainage of the sinuses may occur due to may project into one of the nasal vestibules mechanical obstruction of septal deviations or (called dislocation of anterior end of the by compensatory hypertrophy of turbinates. Anterior rhinoscopy Headache and facial neuralgia might occur shows deflection of the cartilaginous or bony because of defective aeration and impinge- septum or combination of both. This occurs because of stretching the mucosal vessels complicated with dryness of the mucosa and associated nose picking. Treatment of Deviated Nasal Septum Surgical correction is done to relieve the patient of symptoms. Diseases of the Nasal Septum 185 Submucous Resection of Septum the septum and also to reduce bleeding during surgery. Deviated nasal septum producing symp- Steps of Operation toms like nasal obstruction. When the deviated septum is a predis- cutaneous junction, usually on the posing factor for sinusitis or recurrent convex side of the deflection. With an elevator the mucoperichond- ing to the poor development of the teeth rial flap is elevated and the cartilage and mouth. Deviated septum preventing access for cartilage anteriorly leaving a strip for removal of polypi or ethmoidectomy. The incision is made operation may be needed for complete to the subperichondrial space of the other removal of the polypi. To gain, access for other intranasal rated from the mucoperichondrium of operations, for example trans-sphenoidal the other side without tearing the flap. To reduce the roominess in unilateral retract two mucoperichondrial flaps atrophic rhinitis. A ribbon gauze pack soaked then removed with Ballenger’s knife or in xylocaine is packed into the nose with an Luc’s forceps. The mucoperiosteum may idea to anaesthetise the sphenopalatine need elevation from the perpendicular ganglion and its emerging nerves at the plate of ethmoid, vomer and maxillary posterior end of the middle turbinate. The crest, if there is an associated bony pack is carried high up in the nose to block deviation which is then removed. Cartilaginous and bony spurs are supplemented by an intramuscular injection removed. The flaps are approximated and may be Surgery starts half an hour later after local stitched. The nose is packed using merocel pack adrenaline that helps further to anaesthetise to prevent mucosal trauma. The patient is given antibiotics and This operation is not advocated for child- analgesics. Subsequently the nose is operation if performed in young age may cleaned of the clots and discharge and interfere with the development of the facial ointment is applied. Secondary haemor- of septoplasty is the correction of the deviated rhage may occur after 5 to 6 days and is due septum with minimal sacrifice of its structure. Septal haematoma or abscess Septoplasty is indicated when the deviation may occur. Perforation: Septal perforation may occur process of the frontal bone to nasal spine of if tears in the mucoperichondrial flaps the maxilla.
Oerskovia also produces extensively branching filaments which break up into motile rods and coccoid elements generic 100mg zenegra with mastercard. However zenegra 100 mg with visa, its appearance on Gram stain is quite dissimilar to Dermatophilus and it grows anaerobically order zenegra 100mg with mastercard. It is interesting in that it grows much better on blood agar than on enriched chocolate agar and is catalase positive when grown aerobically but negative when grown anaerobically purchase on line zenegra. Of the other genera with aerotolerant species or strains, it can be said that, if catalase positive they will be Propionibacterium, while if catalase negative they will be Actinomyces or Lactobacillus. Colonial and cellular morphology should enable separation of the latter two genera. The non-acid-fast, non-sporing, regular, Gram positive rods include Listeria and Erysipelothrix as the most important genera. Erysipelothrix is -hemolytic, catalase negative and produces H S2 in triple sugar iron agar. Two other genera usually considered in this group are Brochothrix and Kurthia; these are of little, if any, clinical significance. Brochothrix is very similar to Listeria but is nonmotile and does not grow at 37C. Kurthia is a strict aerobe, oxidase positive, esculin negative and glucose negative. Any Gram positive rods which are not sporing, branching, filamentous or acid-fast, show some degree of pleomorphism and tend to stain irregularly are described as coryneform. This can include a lot of genera other than Corynebacterium, and many corynebacteria are quite regular both in cellular morphology and in Gram staining reaction. All one can do is to be sure that the organism is not an unusual representative of one of the other genera mentioned above and then attempt to identify it using the table in Balows, which includes all the species of Corynebacterium and related species of any medical relevance. If identification is not possible by this means, all that remains is usually to label it a ‘diphtheroid’. This includes a large number of environmental and plant pathogen species of Corynebacterium, as well as such environmental and dairy genera as Caseobacter, Aureobacterium, Microbacterium, Agromyces, Arthrobacter, Brevibacterium, Cellulomonas and Micromonospora. Arthrobacter can be identified, with some difficulty, by its rod cocci rod cycle and other properties. This approach can be characterised as a systematic one guided by knowledge and verified by close attention to the properties of Diagnosis and Management of Infectious Diseases Page 424 Identification of Isolates the organism, with stress being placed on such basic properties as colonial and cellular morphology, smell, growth characteristics, possession of an oxidative or fermentative metabolism, oxidase and catalase reactions, and such other biochemical reactions as are known to be close to invariant for the organism. It is important not to be misled by a single anomalous test, whether this is due to poor technique, poor information or the nature of the organism. It is also necessary to realise the limits of one’s expertise and when to yell for help. Diagnosis and Management of Infectious Diseases Page 425 Chapter 28 Antimicrobial Susceptibility Testing The aim of the exercise is to find antibiotics which will be useful in eliminating an infection caused by an isolated organism in a given clinical situation. Selection of antibiotics, method of testing, and reporting of results are all important. Appropriate to patient: Age: Neonate: chloramphenicol, sulphonamides, cotrimoxazole contraindicated. Breastfeeding: chloramphenicol, quinolones, sulphonamides, azithromycin, tetracyclines, cotrimoxazole contraindicated. Genetic factors: sulphonamides in glucose-6-phosphate dehydrogenase deficient infants. Interaction with other drugs: Antibiotic potentiating or diminishing effect of other drug. Clinical condition of patient: Renal failure: polymyxin B, nalidixic acid, sulphonamides, cotrimoxazole, tetracycline contraindicated. Choosing Antibiotics to Test Above considerations +: Able to be tested by method used. Antibiotic may not be testable because: Intrinsic qualities of antibiotic, eg, poor diffusibility, need for acidification to become active. If it is known which antibiotic the patient is being, or will be, treated with, this should be tested if at all appropriate. In mixed infections with multiple organisms, all possible efforts should be made to find a single antibiotic appropriate for treating all significant organisms. All methods may give false susceptible results for some organisms showing intrinsic resistance, which may not be detected—eg, Klebsiella and ampicillin [see table of intrinsic resistances below]. Within limits, specificity is more important than sensitivity—ie, no false susceptibles, even at the expense of missing some that could be susceptible. Intrinsic/Easily Induced Resistances Organism Report Resistant to Acinetobacter all cephalosporins Enterobacter, Serratia, Citrobacter, Aeromonas, ampicillin, cephalosporins, augmentin, ticarcillin Providencia rettgeri, Providencia stuartii, Morganella morganii Proteus vulgaris, Proteus penneri ampicillin, cephalosporins, ticarcillin, nitrofurantoin, tetracycline Proteus mirabilis tetracycline, nitrofurantoin, colistin Klebsiella ampicillin, ticarcillin Yersinia enterocolitica ampicillin Pseudomonas aeruginosa ampicillin, cephalothin, chloramphenicol, cotrimoxazole, tetracycline, augmentin Stenotrophomonas maltophilia ampicillin, augmentin, all cephalosporins, ciprofloxacin, norfloxacin, tetracycline, aminoglycosides Methods A standard method should be used. Agar dilution is regarded as the ‘gold standard’, but results are influenced by agar, do not reflect high mutation rates, are somewhat time-consuming and prone to ‘clerical’ errors. Diagnosis and Management of Infectious Diseases Page 427 Antimicrobial Susceptibility Testing The most suitable method overall appears to be broth microdilution (for both aerobes and anaerobes). Preparation of inocula directly from growth on agar plates gives as reproducible results as preliminary growth in broth. Commercially available products are convenient and accurate but relatively expensive and restricted to the range supplied by the manufacture. Broth dilution methods also have problems with sulphonamides, trimethoprim and aminoglycosides. The Vitek semi-automated form of the broth microdilution method can produce results for Enterobacteriaceae in a minimum of 4 hours and for staphylococci in a minimum of 6 hours, allowing 70% of Vitek tests to be reported the same day. Because of this and because of its convenience when handling large numbers of isolates, it is widely used in larger laboratories. It is also the most accurate (specificity 93%) routine method for testing methicillin susceptibility, while also showing high sensitivity (96%). However, it has problems with testing ampicillin, cephalosporins and augmentin against Enterobacteriaceae, and all antibiotics against Pseudomonas. Also, the relatively large inoculum needed may result in false results due to mixed cultures, which may not be detected by the operator. Broth macrodilution methods are laborious, time-consuming and require careful technique. They have the disadvantages that antimicrobial dilutions are required, they are not applicable to urgent direct susceptibility testing, and are not easily individualised. However, no antimicrobial dilutions are required, it is applicable to urgent susceptibility testing, and antimicrobial tests are easily individualised. Because of this, agar diffusion methods are probably still the most widely used overall. They cannot be used for slow-growing organisms or for poorly diffusing antibiotics or for those whose activity depends on conditions which cannot be duplicated in the method. If a susceptible isolate is defined as one where there has been a prior correlation with a favourable clinical response, the test predicts a successful outcome to antimicrobial therapy. Zone sizes may vary for different classes of organisms (eg, ampicillin with Enterobacteriaceae and with Staphylococci). If the category ‘intermediate’ is reported, this should indicate that the test result is equivocal. A ‘moderately susceptible’ result should be reported to indicate susceptibility under certain conditions. Enterococci, other streptococci and non-penicillinase- producing, penicillin-susceptible organisms, when tested against penicillin or ampicillin, should be reported as ‘moderately susceptible’ rather than as ‘intermediate’; this applies especially to enterococci, which for blood or serious invasive tissue infections require high dosage of penicillin or ampicillin, generally combined with an aminoglycoside for improved therapeutic response and bactericidal action. For streptococci, staphylococci and other penicillin-susceptible organisms, ‘susceptible’ means ‘very susceptible’. When an intermediate result is obtained with staphylococci, the strains should be further investigated to determine if they are heteroresistant. The method is sensitive (> 96%) in testing for methicillin resistant staphylococci but its specificity is only 50%. The Stokes method compares zone sizes obtained for a test organism with those for a control organism. It is now rarely used in Australia because it is somewhat more troublesome to use and, in many cases, is less accurate than other disc diffusion methods. It does, however, show a specificity of 88% in testing staphylococci for methicillin resistance, while also having high sensitivity (> 96%) Diagnosis and Management of Infectious Diseases Page 428 Antimicrobial Susceptibility Testing The E-test uses a strip with a gradient of antibiotic. The method is simple to use but expensive and is not useful for detecting extended broad spectrum beta-lactamase production. Within limits, zone sizes in disc diffusion susceptibility testing are a function of inoculum density, lower densities producing larger zones. Depending on relative diffusion rates and stability characteristics of the antimicrobial and growth characteristics of the organism at room temperature and at incubation temperature, prediffusion prior to incubation may increase or decrease zone sizes; an increase is usual but by no means universal.
The deoxygenated blood that enters the right side of the heart is pumped into the aorta which is abnormally connected to the right ventricle cheap 100 mg zenegra visa, and therefore deoxygenated blood returns to the body without the benefit of improving its oxygen- ation order zenegra 100mg without a prescription. In the parallel circulation order zenegra 100mg overnight delivery, oxygenated blood returning to the left heart goes back to the lungs through the abnormally connected pulmonary artery order zenegra 100mg with visa, therefore, depriving the body from receiving oxygenated blood. Mixing of oxygenated and deoxygenated blood at one or more of three levels is required for survival. Severe hypoxemia and subsequent anaerobic metabolism result in lactic acid production and metabolic acidosis, eventually leading to cardiogenic shock. Clinical Manifestations Transposition of the great arteries, as with most congenital heart defects, is well tolerated during fetal life. Depending on the degree of mixing of oxygen- ated and deoxygenated blood at the atrial, ventricular, and arterial levels, patients can become severely cyanotic within the first hours or days of life. Closure of the ductus arteriosus, one of the potential levels of mixing of deoxygenated and oxygenated blood, leads to cyanosis and acidosis. After a few days of life, infants often become more tachyp- neic, but this can be subtle and easily missed. The second heart sound is single as the pul- monary valve closure becomes inaudible due to its posterior position far away from the chest wall (Fig. Occasionally, a continuous murmur caused by flow across the patent ductus arteriosus may be heard. The second heart sound is single due to the posterior displacement of the pulmonary valve away from the chest wall. Over time, chest X-ray may demonstrate an enlarged cardiac silhouette with a marked increase in pulmonary vasculature (Fig. As time progresses, right ventricular hypertrophy may become apparent, demonstrated by tall R in V1 and deep S in V6. The mediastinum is narrow due to the parallel arrangement of the transposed great vessels 190 D. Views directed from the subcostal region allow the determination of the relationships between the ventricles and their respective great arteries. Views along the parasternal long axis demonstrate the great artery that arises from the left ven- tricle to travel downward and bifurcate, thus making it a pulmonary artery. Views along the parasternal short axis demonstrate both semilunar valves (aortic and pul- monary) en face, which is not typical in a normal heart. Further imaging reveals that the anterior vessel is the aorta (achieved by demonstrating that the coronary arteries originate from it). Color Doppler flow studies demonstrate a right to left shunt at the level of the ductus arteriosus. The foramen ovale is a relatively small communication that does not permit a significant amount of flow across it. A balloon tipped catheter is fed, most often from the right groin, into the right atrium and passed across the foramen ovale into the left atrium. At this point, the balloon is inflated and then rather harshly pulled back into the right atrium, creating a tear in the atrial septum that allows more adequate mixing of blood and thus increasing oxygen saturation, at least temporarily. Once the ductus arteriosus spontaneously closes, patients develop a severe metabolic acidosis and often rapidly deteriorate. This surgical intervention involves transecting each great artery above the valves, which stay in place. The arteries are then “switched” back to their normal locations resulting in a complete anatomic correction for this lesion. The coronary arteries are also removed from the native aortic root with a “button of tissue” from the native aorta surrounding the orifice and are reimplanted in the “new” aortic root. Once repaired, the relocated great vessels are frequently referred to as the “neo-aorta” and “neo-pulmonary artery. The two atrial switch procedures differed in technical aspects, but shared the objective of switching the atrial flow of blood via crisscrossing baffles across the atria. Ultimately, deoxygenated blood is directed to the left ventricle, which pumps blood to the pulmonary artery and the oxygenated blood is directed to the right ventricle which pumps blood to the aorta. These procedures are no longer performed because they leave the right ventricle in the systemic position which can fail over time. In addition, the atrial baffles create excessive scarring within the atria resulting in significant atrial arrhythmias. The etiology is frequently multifactorial consisting most commonly of a combination of excessive tension on the branch pulmonary arteries following the switch procedure as well as a discreet narrowing along the suture lines of the repair. In addition, neo-aortic insufficiency is common due to the fact that the neo-aortic valve is actually the native pulmonary valve and is not normally exposed to systemic pressures. A newborn infant is evaluated by the on call pediatrician because the nurse notes that the child appears “dusky. The pregnancy and delivery were uncomplicated and the patient had previously been doing fine in the nursery, breastfeeding without difficulty. On closer examination, he is quite tachypneic with a respiratory rate greater than 60. A pulse oximeter placed on the right arm measures 55%; on the left leg, it reads 75%. The oxygen saturations remain unchanged after the patient is placed on 100% oxygen by nasal cannula for several minutes. On initial assessment, this presentation could point to a range of anomalies, including respiratory or neurologic disease, along with systemic infection; however, the presence of tachypnea without associated retractions, decreased breath sounds, or grunting, and the failure of his oxygen saturations to improve even marginally with supplemental oxygen point towards a cyanotic con- genital heart lesion with right-to-left shunting. Most likely potential causes of severe cyanosis include transposition of the great arteries, tricuspid atresia, pulmo- nary atresia, and total anomalous pulmonary venous return. The reverse differen- tial cyanosis noted in this child strongly suggests transposition of the great arteries. Given the likelihood of a ductal-dependent cyanotic heart lesion, the patient is started on prostaglandin with improvement in both pre- and post-ductal oxygen saturations. A 16-year-old young woman presents to her pediatrician for a routine physical exam. She is a very active young woman who participates in multiple varsity sports in her high school. She has no particular complaints, but is noted to have a low resting heart rate of 45 beats per minute on initial vital signs. Although her pedia- trician feels that her low heart rate is reflective of her status as an athlete, she is referred to a cardiologist for further evaluation. The remainder of the physical exam, including cardiac aus- cultation, is unremarkable except for single second heart sound. Her left sided ventricle is morphologically consistent with that of a right ventricle and her right sided ventricle appears to be a morpho- logically left ventricle. There is little to no tricuspid or mitral valve regurgitation and her biventricular systolic function is normal. An exercise stress test is sched- uled for the next day and she performs remarkably well, exercising well into stage V (over 15 min) on a standard Bruce protocol. She has no evidence of dysrhythmia during the stress test and her heart rate and blood pressure appropriately increase with peak exercise. At this time she is completely healthy and able to participate fully in competitive athletics. No medication or intervention is warranted at this time and she is followed on yearly basis for signs of ventricular failure such as exercise intolerance. She and family are aware that in the future, the systemic right ventricle may “tire out” necessitating medical and possibly surgical therapy. Felten Key Facts • The pathology of pulmonary atresia with intact ventricular septum ranges between two extremes. After surgical or interventional cardiac catheterization repair, patency of ductus arteriosus is still needed till forward flow across the right heart and pulmonary valve is established; this may require several days or weeks to achieve. The pulmonary valve/arteries are atretic, thus preventing blood from the right heart to reach the pulmonary circulation. In a variation of this lesion, there may be incompetence of the tricuspid valve, lead- ing to severe tricuspid regurgitation with dilation of the right ventricle due to back and forth flow of blood through the incompetent tricuspid valve.
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