PEDIATRIC SURGERY UPDATE ©
VOLUME 41, 2013


PSU Volume 41 No 01 JULY 2013

Acquired Jeune's Syndrome

Jeune's syndrome, also known as asphyxiating thoracic dysplasia, is a type of thoracic dystrophy with severe narrow thorax leading to respiratory distress and even death in its more severe form. Jeune's syndrome either is congenital (autosomal recessive) or acquired. The acquired form of Jeune's syndrome was described in 1996 in children who had undergone repair of pectus excavatum chest wall deformity utilizing the traditional open (Ravitch) approach with subperichondrial resection of deformed cartilages and transverse osteotomy performed too early an age (less than four years of age). Permanent impairment of normal chest wall growth and subsequent restriction of lung expansion during respiration creates this type of acquired form of the disease. Years later after the primary procedure for pectus these children developed progressive dyspnea with mild exertion associated to restrictive pulmonary function tests with forced vital capacity (FVC) of 30-50% and forced expiratory volume in one second (FEV1) of 30-60% of predicted values. This acquired restrictive thoracic dystrophy is due to an aggressive resection of the involved deformed cartilages including the second costal cartilage. This complication does not occur using the actual minimally invasive repair of pectus excavatum (Nuss technique). Diagnosis is done using pulmonary function tests and three-dimensional CT reconstruction of the chest. Management of acquired Jeune's syndrome includes displacing the sternum forward with a splint or median sternotomy with interposition of autologous rib grafts to increase the chest wall diameter (Weber technique). Substantial improvement in PFT and clinical symptoms can be achieved with the sternal split technique though long-term evaluation is awaiting results.  

References:
1- de Vries J, Yntema JL, van Die CE, Crama N, Cornelissen EA, Hamel BC: Jeune syndrome: description of 13 cases and a proposal for follow-up protocol. Eur J Pediatr. 169(1):77-88, 20102- Weber TR, Kurkchubasche AG: Operative management of asphyxiating thoracic dystrophy after pectus repair. J Pediatr Surg. 33(2):262-5, 19983- Fokin AA, Robicsek F: Acquired deformities of the anterior chest wall. Thorac Cardiovasc Surg. 54(1):57-61, 20064- Weber TR: Further experience with the operative management of asphyxiating thoracic dystrophy after pectus repair. J Pediatr Surg. 40(1):170-3, 20055- Phillips JD, van Aalst JA: Jeune's syndrome (asphyxiating thoracic dystrophy): congenital and acquired. Semin Pediatr Surg. 17(3):167-72, 2008 6- Lopushinsky SR, Fecteau AH: Pectus deformities: a review of open surgery in the modern era. Semin Pediatr Surg. 17(3):201-8, 2008


Metal Allergy

Jewelry, dental and surgical implants from craniofacial, orthopedic, neurosurgical and pediatric surgery physicians can lead to metal allergy in children. As many as 13% of patients are sensitive to nickel, cobalt or chromium. Metal allergy from nickel is the most common contact allergy in the United States and Europe. The classical symptom of dermatitis caused by nickel is a rash in the earlobes, periumbilical region or wrist resulting from contact with costume jewelry, buttons and zipper. Metal allergy is a typical delayed type IV hypersensitivity reaction caused by T-lymphocytes reaction. CD8 and CD4 cells cause cytotoxic and inflammatory response to the metal. Children with metal allergy usually elicit a past history of atopy including allergic rhinitis, asthma, eczema and urticarial rash. Metal allergies are frequently misdiagnosed as surgical infections. Symptoms of inflammation such as pain, warmth, erythema and swelling can be seen over the implant, including pericarditis and pleural effusion in those in a thoracic position. As a screening measure to determine if a child can or might develop metal allergy to an implant the following should be evaluated: 1- history of allergy to jewelry, orthodontic braces, metal buttons on clothing and food. 2- History of previous atopy and eczema. If any of the above indications are found, a dermal patch test should be performed. This patch test contains 23 allergens and allergen mixes that cause up to 80% of allergic contact dermatitis cases. Should the child be found to have metal allergy implants of titanium should be considered, since titanium does not produce allergic reactions but are more expensive.     

References:
1- Mortz CG, Lauritsen JM, Bindslev-Jensen C, Andersen KE: Nickel sensitization in adolescents and association with ear piercing, use of dental braces and hand eczema. The Odense Adolescence Cohort Study on Atopic Diseases and Dermatitis (TOACS). Acta Derm Venereol. 82(5):359-64, 2002
2- Dotterud LK, Falk ES: Metal allergy in north Norwegian schoolchildren and its relationship with ear piercing and atopy. Contact Dermatitis. 31(5):308-13, 1994
3- Kalimo K, Mattila L, Kautiainen H: Nickel allergy and orthodontic treatment. J Eur Acad Dermatol Venereol. 18(5):543-5, 2004
4- Katting B, Brehler R, Traupe H: Allergic contact dermatitis in children: strategies of prevention and risk management. Eur J Dermatol. 14(2):80-5, 2004
5- Rushing GD, Goretsky MJ, Gustin T, Morales M, Kelly RE Jr, Nuss D: When it is not an infection: metal allergy after the Nuss procedure for repair of pectus excavatum. J Pediatr Surg. 42(1):93-7, 2007
6- Thyssen JP, Jakobsen SS, Engkilde K, Johansen JD, SA¸balle K, Menna T: The association between metal allergy, total hip arthroplasty, and revision. Acta Orthop. 80(6):646-52, 2009

PRETEXT

The PRETEXT (PRE Treatment EXTent of disease) system was designed by the International Childhood Liver Tumor Strategy Group (SIOPEL) for staging and risk stratification of liver tumors, namely hepatoblastoma, hepatocellular carcinoma and epithelioid hemangioendothelioma. PRETEXT describes tumor extent before any therapy allowing different groups to have a more effective comparison in future studies. PRETEXT staging is based on Couinaud's liver segmentation grouping the liver into four sections: segment 2 and 3 (left lateral section), segment 4a and 4b (left medial section), segments 5 and 8 (right anterior section) and segments 6 and 7 (right posterior section). The PRETEXT number is derived by subtracting the highest number of contiguous liver sections that are not involved by tumor from four. PRETEXT also utilizes other criteria such as involvement of the caudate lobe (designated C), involvement of the inferior vena cava or hepatic veins (V), involvement of the portal veins (P), extrahepatic abdominal disease (E) and distant metastasis (M). Other high risk criteria include tumor rupture or intraperitoneal hemorrhage at diagnosis (H1) and alpha fetoprotein levels below 100 ug/L. In PRETEXT I one section is involved and three are free. This group includes only a small portion of all cases. In PRETEXT II one or two sections re involved, but two adjoining sections are free. They are limited to the right lobe or left lobe of the liver.  In PRETEXT III two or three sections are involved and no two adjoining sections are free. The unifocal tumors in this category spare only the left lateral or right posterior section. This group is relatively common. In PRETEXT IV all four sections are involved. Involvement of the caudate lobe is a potential predictor of a poor outcome. Extrahepatic disease refers to diaphragm involvement, peritoneal seeding, ascites and abdominal lymph node metastasis. Distant metastasis is manly to the lung. 

   Couinaud's liver segmentation

References:
1- Brown J, Perilongo G, Shafford E, Keeling J, Pritchard J, Brock P, Dicks-Mireaux C, Phillips A, Vos A, Plaschkes J: Pretreatment prognostic factors for children with hepatoblastoma-- results from
the International Society of Paediatric Oncology (SIOP) study SIOPEL 1. Eur J Cancer. 36(11):1418-25, 2000
2- Perilongo G, Shafford E, Plaschkes J; Liver Tumour Study Group of the International Society of Paediatric Oncology: SIOPEL trials using preoperative chemotherapy in hepatoblastoma. Lancet Oncol. 1:94-100, 2000
3- Roebuck DJ, Aronson D, Clapuyt P, Czauderna P, de Ville de Goyet J, Gauthier F, Mackinlay G, Maibach R, McHugh K, Olsen OE, Otte JB, Pariente D, Plaschkes J, Childs M, Perilongo G; International Childrhood Liver Tumor Strategy Group: 2005 PRETEXT: a revised staging system for primary malignant liver tumours of childhood developed by the SIOPEL group. Pediatr Radiol. 37(2):123-32, 2007
4- Roebuck DJ: Assessment of malignant liver tumors in children. Cancer Imaging. 9: S98-S103, 2009
5- Meyers RL, Czauderna P, Otte JB: Surgical treatment of hepatoblastoma. Pediatr Blood Cancer. 59(5):800-8, 2012
6- Tajiri T, Kimura O, Fumino S, Furukawa T, Iehara T, Souzaki R, Kinoshita Y, Koga  Y, Suminoe A, Hara T, Kohashi K, Oda Y, Hishiki T, Hosoi H, Hiyama E, Taguchi T: Surgical strategies for unresectable hepatoblastomas. J Pediatr Surg. 47(12):2194-8, 2012


PSU Volume 41 No 02 AUGUST 2013

Duhamel Procedure

In 1956 Bernard Duhamel first described a rectorectal pull-through procedure. Since then, the Duhamel is a long standing pull-through procedure performed for the management of Hirschsprung's disease (HD). In short, the procedure entails pulling the proximal normal ganglionic bowel posterior to the aganglionic rectum through the presacral space into the anus. A common lumen is created with mechanical devices between the ganglionic and aganglionic rectal bowel. The surgical approach to HD has changed from building an initial temporary colostomy using a two or even three stage procedures, to a one-stage surgical procedure in the neonatal period. As with any other kind of surgical procedure for Hirschsprung's disease the child can develop postoperative constipation, soiling or incontinence. Constipation and soiling after the Duhamel procedure often are associated with an anterior rectal pouch caused by a colorectal spur. Constipation also may result from outlet obstruction caused by residual spasticity of the internal sphincter or too long rectal aganglionic bowel. Extended resection of the aganglionic rectum reduces the incidence of fecalomas formation. Suboptimal outcome after operation for Hirschsprung's' disease includes associated neuronal intestinal dysplasia, total colonic involvement, significant neurological impairment and history of enterocolitis all of which may result in abnormal colonic motility in the remaining ganglionic bowel. Chronic bleeding after Duhamel is caused by an incomplete section of the septum between rectum and pull-through segment leaving the feeding artery on the tip of the side-to-side anastomosis. After rectosigmoidectomy alteration in bladder function such as increase bladder capacity and urinary residual has been described. Open and laparoscopic Duhamel procedure has similar outcomes.

References:
1- Baillie CT, Kenny SE, Rintala RJ, Booth JM, Lloyd DA: Long-term outcome and colonic motility after the Duhamel procedure for Hirschsprung's disease.J Pediatr Surg. 34(2):325-9, 1999
2- van der Zee DC, Bax KN: One-stage Duhamel-Martin procedure for Hirschsprung's disease: a 5-year follow-up study. J Pediatr Surg. 35(10):1434-6, 2000
3- Mattioli G, Castagnetti M, Martucciello G, Jasonni V: Results of a mechanical Duhamel pull-through for the treatment of Hirschsprung's  disease and intestinal neuronal dysplasia. J Pediatr Surg. 39(9):1349-55, 2004
4- Chiengkriwate P, Patrapinyokul S, Sangkhathat S, Chowchuvech V: Primary pull-through with modified Duhamel technique: 1 institution's experience. J Pediatr Surg. 42(6):1075-80, 2007
5- Marquez TT, Acton RD, Hess DJ, Duval S, Saltzman DA: Comprehensive review of procedures for total colonic aganglionosis. J Pediatr Surg. 44(1):257-65, 2009
6- Nah SA, de Coppi P, Kiely EM, Curry JI, Drake DP, Cross K, Spitz L, Eaton S, Pierro A: Duhamel pull-through for Hirschsprung disease: a comparison of open and laparoscopic techniques. J Pediatr Surg. 47(2):308-12, 2012


Prevention of NEC

Necrotizing enterocolitis (NEC) is the most common surgical emergency in the neonatal intensive care unit (NICU) associated with a significant morbidity and mortality. Due to advances in neonatal care survival among premature and low birth weight infants has improved though the mortality due to NEC has increased. Prevention of NEC should be of upmost importance in most NICU. One of the most important preventive measures in the development of NEC is feeding infants at risk with breast milk as opposed to formula milk. If fortification of breast milk is necessary to achieve adequate growth, then a fortifier based on human milk lowers the incidence of NEC. Another factor associated with lowering the incidence of NEC is whether to use early or delayed enteral feedings. Current metaanalysis does not support the use of a delayed introduction or slower rate of enteral feeds to prevent NEC. They slower the weight gain and take longer time to full feeding. Adverse effect of immunoglobulin administration or prophylactic enteral antibiotics precluded their use as preventive measure. Prophylactic antibiotics increase the colonization of resistant bacteria. The other measure with strong evidence to use for NEC prevention is the administration of probiotics and modulation of feeding regimens in infants at high risk. Studies investigating specific components of breast milk and probiotics responsible for these protective effects have identified several molecules with therapeutic potential such as erythropoietin, glutamine, and epidermal growth factor all of which strengthen the gut barrier. Probiotics reduce intestinal permeability, promote peristalsis, increase mucin secretion, activate anti-inflammatory TLR9, downregulate proinflammatory cytokines and upregulated antiinflammatory mediators.

References:
1- Morgan JA, Young L, McGuire W: Pathogenesis and prevention of necrotizing enterocolitis. Curr Opin Infect Dis. 24(3):183-9, 2011
2- Berman L, Moss RL: Necrotizing enterocolitis: an update. Semin Fetal Neonatal Med. 16(3):145-50, 2011
3- Ganguli K, Meng D, Rautava S, Lu L, Walker WA, Nanthakumar N: Probiotics prevent necrotizing enterocolitis by modulating enterocyte genes that  regulate innate immune-mediated inflammation. Am J Physiol Gastrointest Liver Physiol. 304(2):G132-41, 2013
4- Downard CD, Renaud E, St Peter SD, Abdullah F, Islam S, Saito JM, Blakely ML, Huang EY, Arca MJ, Cassidy L, Aspelund G; 2012 American Pediatric Surgical Association Outcomes Clinical Trials Committee. Treatment of necrotizing enterocolitis: an American Pediatric Surgical Association Outcomes and Clinical Trials Committee systematic review. J Pediatr Surg. 47(11):2111-22, 2012
5- Bernardo WM, Aires FT, Carneiro RM, Sá FP, Rullo VE, Burns DA: Effectiveness of probiotics in the prophylaxis of necrotizing enterocolitis in preterm neonates: a systematic review and meta-analysis. J Pediatr (Rio J). 89(1):18-24, 2013
6- Raval MV, Hall NJ, Pierro A, Moss RL: Evidence-based prevention and surgical treatment of necrotizing enterocolitis-a review of randomized controlled trials. Semin Pediatr Surg. 22(2):117-21, 2013


Music-Induced Stress Reduction

Music intervention has been found to reduce procedure related anxiety for patients in the pre- and intraoperative setting. Studies have shown that music reduced self-reported stress levels and improve perceptions of patient-oriented service in visitors to the surgery/intensive care unit waiting room. Adults who listened to music while waiting with their children in the pediatric emergency department, reported lower anxiety level than those who did not listen to music. The level of formal education is inversely correlated to degree of music-induced anxiety reduction. Music improved the work environment for hospital staff and facilitated their interactions with friends and family of patients. Allowing patients control over music selection and providing uninterrupted time for music listening gives the patients an enhanced sense of control in an environment that often controls them. Music alone and music assisted relaxation techniques significantly decreased arousal due to stress. Further analysis revealed that the amount of stress reduction was significantly different when considering age, type of stress, music assisted relaxation technique, musical preference, previous music experience, and type of intervention. Music specifically induces an emotional response similar to a pleasant experience or happiness. Music in the operating room has immeasurable effects. It can prevent distraction, minimize annoyance, reduce stress, reduce the demands for analgesic and anesthetics, and diminish the anxiety of patients, staff and users.

References:
1- Pelletier CL: The effect of music on decreasing arousal due to stress: a meta-analysis.  J Music Ther. 41(3):192-214, 2004
2- Suda M, Morimoto K, Obata A, Koizumi H, Maki A: Emotional responses to music: towards scientific perspectives on music therapy. Neuroreport. 19(1):75-8, 2008
3- Makama JG, Ameh EA, Eguma SA: Music in the operating theatre: opinions of staff and patients of a Nigerian teaching hospital. Afr Health Sci. 10(4):386-9, 2010
4- Moris DN, Linos D: Music meets surgery: two sides to the art of "healing". Surg Endosc. 27(3):719-23, 2013
5- Tilt AC, Werner PD, Brown DF, Alam HB, Warshaw AL, Parry BA, Jazbar B, Booker A,  Stangenberg L, Fricchione GL, Benson H, Lillemoe KD, Conrad C: Low degree of formal education and musical experience predict degree of music-induced stress reduction in relatives and friends of patients: a single-center, randomized controlled trial. Ann Surg. 257(5):834-8, 2013
6- Beaulieu-Boire G, Bourque S, Chagnon F, Chouinard L, Gallo-Payet N, Lesur O: Music and biological stress dampening in mechanically-ventilated patients at the  intensive care unit ward-a prospective interventional randomized crossover trial. J Crit Care. Mar 14, 2013



PSU Volume 41 No 03 SEPTEMBER 2013

Octreotide

Octreotide is a synthetic peptide analog of somatostatin with the same pharmacologic effect. Octreotide has a longer half-life in circulation and higher potency than somatostatin. Octreotide decreases the production of gastrointestinal peptides, such as gastrin, secretin, gastric inhibitory peptide, cholecystokinin, neurotensin, motilin, and pancreatic polypeptide. Octreotide has several therapeutic uses in children. Octreotide significantly reduced the amount of blood transfusions in children with severe gastrointestinal bleeding and hemodynamic instability from acute variceal hemorrhage. Octreotide successfully reduced bleeding in a patient with typhlitis and cecal ulceration prior to surgery but failed to control massive bleeding in children with a Meckel's diverticulum. Octreotide inhibits pancreatic secretion and can be of help in resolution of pancreatic pseudocysts allowing healing of pancreatic duct with resolution of ascites. It can significantly reduce serum lipase levels and reduce the clinical need for analgesics in acute pancreatitis. Octreotide is effective in the management of chylothorax by shortening the TPN duration, hospital stay and avoiding surgery since it reduces thoracic duct lymph flow and absorption. Octreotide is effective in reducing stool output in children with a variety of disorders, including massive ileostomy losses, intestinal fistula, congenital microvillus atrophy, idiopathic secretory diarrhea, carcinoid tumor, cryptosporidium diarrhea and watery diarrhea hypokalemia achlorhydria syndrome. Octreotide should be avoided in patients with diagnosed or suspected congenital long Q–Tc syndrome and cautiously used in conjunction with drugs that prolong Q–T interval. Because of its inhibitory action on insulin, octreotide has been associated with glucose intolerance and hyperglycemia that may necessitate insulin therapy.

References:
1- Paget-Brown A, Kattwinkel J, Rodgers BM, Michalsky MP: The use of octreotide to treat congenital chylothorax. J Pediatr Surg. 41(4):845-7, 2006
2- Al-Hussaini A, Butzner D: Therapeutic applications of octreotide in pediatric patients. Saudi J Gastroenterol. 18(2):87-94, 2012
3- Nardone G, Rocco A, Balzano T, Budillon G: The efficacy of octreotide therapy in chronic bleeding due to vascular abnormalities of the gastrointestinal tract. Aliment Pharmacol Ther. 13(11):1429-36, 1999
4- Heikenen JB, Pohl JF, Werlin SL, Bucuvalas JC: Octreotide in pediatric patients. J Pediatr Gastroenterol Nutr. 35(5):600-9, 2002
5- Sahin Y, Aydin D: Congenital chylothorax treated with octreotide. Indian J Pediatr. 72(10):885-8, 2005
6- Helin RD, Angeles ST, Bhat R: Octreotide therapy for chylothorax in infants and children: A brief review. Pediatr Crit Care Med. 7(6):576-9, 2006


Peritoneovenous Shunt

Peritoneovenous shunt (PVS), also known as Leveen or Denver shunt, is a shunt utilized to manage medically intractable ascites in adults and children. These shunts allow ascitic fluid to flow down a pressure gradient from the peritoneal cavity to the venous circulation and have a valve mechanism that prevents backflow of blood if the venous pressure rises above the intraabdominal pressure. The advantage of the Denver shunt is that the valve chamber lies in the subcutaneous tissue and therefore can be manually compressed to relieve blockage and promote flow. The shunt can also be flushed percutaneously if necessary. When peritoneal pressure is 3 cm higher than CV pressure the valve opens. PVS can be placed surgically, laparoscopically-assisted or percutaneously. Persistent ascites is rare in children, carries a significant morbidity and is a difficult management problem owing to the massive abdominal distension. Etiology is often related to previous surgery, congenital malformation of  lymphatic channels, or idiopathic. Other causes include inflammatory, neoplastic, traumatic, mechanical obstruction or nonaccidental injury. Conservative and symptomatic management is usually the mainstay of treatment while surgery is indicated when conservative therapy fails. Certain complications have been described in association with the procedure of placing the PVS. One of the major concerns is  diversion of large amounts of fluid into the central circulation, potentially contributing to fluid overload. In anticipation of this potential complication, diuretic therapy is initiated that seemed to avoid this problem. Other reported complications include shunt blockage and leaks, venous thrombosis, disseminated intravascular coagulation, infection, and air embolus during insertion. The PVS is an effective alternative in management for intractable ascites in children.

References:
1- Blaylock RS, Emby D, Hopley M, Toogood JW: The peritoneo-saphenous shunt for palliation of refractory ascites. S Afr J Surg. 39(3):83-5, 2001
2- Sooriakumaran P, McAndrew HF, Kiely EM, Spitz L, Pierro A: Peritoneovenous shunting is an effective treatment for intractable ascites. Postgrad Med J. 81(954):259-61, 2005
3- Matsufuji H, Nishio T, Hosoya R: Successful treatment for intractable chylous ascites in a child using a peritoneovenous shunt. Pediatr Surg Int. 22(5):471-3, 2006
4- Won JY, Choi SY, Ko HK, Kim SH, Lee KH, Lee JT, Lee do Y: Percutaneous peritoneovenous shunt for treatment of refractory ascites. J Vasc Interv Radiol. 19(12):1717-22, 2008
5- Rahman N, De Coppi P, Curry J, Drake D, Spitz L, Pierro A, Kiely E: Persistent ascites can be effectively treated by peritoneovenous shunts. J Pediatr Surg. 46(8): 315–319, 2011
6- Herman R, Kunisaki S, Molitor M, Gadepalli S, Hirschl R, Geiger J: The use of peritoneal venous shunting for intractable neonatal ascites: a short case series. J Pediatr Surg. 46(8):1651-4., 2011


Corpus Luteum Cyst

A corpus luteum cyst (CLC) is a functional ovarian cyst very rarely found in adolescent girls. The cyst develops when the corpus luteum fails to regress following the release of the ovum. CLC may rupture about the time of menstruation and take up to three months to disappear completely. This type of cyst occurs after an egg has been released from a follicle. The follicle becomes a secretory gland known as corpus luteum. Produces large quantity of estrogen and progesterone in preparation for conception, but if pregnancy does not occur it disappears. If it fills with fluid or blood it will grow and create a cyst. The cyst might cause pain by way of torsion, rupture or bleeding. Fertility drugs used to induce an ovulation increase the risk of corpus luteum cyst development. Symptomatic large ovarian cysts will need imaging, genetic marker determination and surgery. Laparoscopy is becoming the favored approach by most pediatric surgeons for the treatment of ovarian cysts with benign imaging and labs characteristics. All surgical procedures for ovarian cysts should  spare functional ovary as much as is technically possible. The management of symptomatic corpus luteum cysts is ovarian cystectomy using the tissue sparing procedure of stripping of the cyst. In cases of endometrioma cysts the amount of ovarian tissue removed together with the cyst is significantly much greater than with the nonendometriotic cysts.                                                           

References:
1- Mayer JP, Bettolli M, Kolberg-Schwerdt A, Lempe M, Schlesinger F, Hayek I, Schaarschmidt K: Laparoscopic approach to ovarian mass in children and adolescents: already a standard in therapy. J Laparoendosc Adv Surg Tech A. 19 Suppl 1:S111-5, 2009
2- Shapiro EY, Kaye JD, Palmer LS: Laparoscopic ovarian cystectomy in children. Urology. 73(3):526-8, 2009
3- Karpelowsky JS, Hei ER, Matthews K: Laparoscopic resection of benign ovarian tumours in children with gonadal preservation. Pediatr Surg Int. 25(3):251-4, 2009
4- Palmara V, Sturlese E, Romeo C, Arena F, De Dominici R, Villari D, Impellizzeri P, Santoro G: Morphological study of the residual ovarian tissue removed by laparoscopy or laparotomy in adolescents with benign ovarian cysts. J Pediatr Surg. 47(3):577-80, 2012
5- Kirkham YA, Kives S: Ovarian cysts in adolescents: medical and surgical management. Adolesc Med State Art Rev. 23(1):178-91, 2012
6- Tessiatore P, Guanà R, Mussa A, Lonati L, Sberveglieri M, Ferrero L, Canavese F: When to operate on ovarian cysts in children? J Pediatr Endocrinol Metab. 25(5-6):427-33, 2012



PSU Volume 41 NO 04 OCTOBER 2013

Thromboprophylaxis

Thromboprophylaxis is utilized to prevent and reduce the incidence of hospital-acquired life-threatening venous thromboembolism (VTE) events such as deep venous thrombosis and pulmonary embolism. The incidence of VTE in children has increased in tertiary care centers. The presence of a central venous catheter is the most prevalent risk factor for VTE in pediatric patients. Risk factors associated with VTE include acute conditions such as major lower extremity orthopedic surgery, spinal cord injury, major trauma to lower extremity, lower extremity central venous catheter, acute infection, burns and pregnancy. Chronic conditions include obesity, estrogen containing medication, inflammatory bowel disease, nephrotic syndrome, known thrombophilia. Other risk factors include past history of previous DVT/PE or family history of VTE in first degree relatives. Adolescent above the 14 years of age with above risk factors should receive prophylaxis. Intervention for thromboprophylaxis includes early and frequents ambulation, good hydration for low risk children; mechanical prophylaxis using graduated compression antiembolic stockings or sequential pneumatic compression for moderate risk; and anticoagulant prophylaxis with enoxaparin or fractionated heparin for high risk patients. For immobile patient sequential compression is preferred. Contraindications for anticoagulation include intracranial hemorrhage, acute stroke, uncontrolled hemorrhage, coagulopathy, incomplete spinal cord injury, allergy and heparin induced thrombocytopenia. Every institution managing children at high risk should institute an algorithm of risk assessment and prophylaxis to prevent VTE. Providing thromboprophylaxis to children is cost-effective.

References:
1- Jackson PC, Morgan JM: Perioperative thromboprophylaxis in children: development of a guideline for management. Paediatr Anaesth. 18(6):478-87, 2008
2- Monagle P, Chalmers E, Chan A, DeVeber G, Kirkham F, Massicotte P, Michelson AD;  American College of Chest Physicians. Antithrombotic therapy in neonates and children: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest. 133(6 Suppl):887S-968S, 2008
3- Raffini L, Trimarchi T, Beliveau J, Davis D: Thromboprophylaxis in a Pediatric Hospital: A Patient-Safety and Quality-Imrpovement Intitative.Pediatrics. 127(5):e1326-32, 2011
4- Parker RI: Thromboprophylaxis in critically ill children: how should we define the "at risk" child? Crit Care Med. 39(7):1846-7, 2011
5- Hanson SJ, Punzalan RC, Arca MJ, Simpson P, Christensen MA, Hanson SK, Yan K, Braun K, Havens PL: Effectiveness of clinical guidelines for deep vein thrombosis prophylaxis in reducing the incidence of venous thromboembolism in critically ill children after trauma. J Trauma Acute Care Surg. 72(5):1292-7, 2012
6- Sharma M, Carpenter SL: Thromboprophylaxis in a pediatric hospital. Curr Probl Pediatr Adolesc Health Care. 43(7):178-83, 2013

Mucopolysaccharidosis

Mucopolysaccharidosis (MPS) are a group of metabolic disorders due to absence or malfunctioning of a lysosomal enzyme needed to breakdown molecules called glycosaminoglycans causing a storage lysosomal disease. Children with MPS are at high-risk for significant perioperative mortality. Excessive secretions, difficult or failed intubation, need for emergency tracheotomy and intraoperative cardiac arrest have been described in MPS patients. The most studied is MPS type I caused by a deficiency of lysosomal enzyme alpha-L-iduronidase producing accumulation of dermatan sulfate and heparan sulfate in the lysosomes. There is a spectrum of clinical disease involvement depending on age of onset, progression, cognitive involvement and organ involvement. Management of children with MPS type I include hematopoietic stem cell transplantation and recombinant human alpha-L-idurodinase enzyme replacement. Disease-related airway issues have been shown to increase the risk of transplant in MPS type I. Many deaths associated to MPS I are due to upper airway obstruction encountered during anesthetic care specially in children with the most severe phenotype. Numerous airway problems have been reported, including obscured airway landmarks owing to excess glycosaminoglycan deposition, copious thick secretions, narrow stiff airways, and difficulty oxygenating owing to glycosaminoglycan deposition within alveoli. Surgical mortality may be greater in these undiagnosed patients who are unlikely to be referred to anesthesiologists with expertise in managing difficult airways or to undergo other precautionary measures. Physicians should become familiar with the physical characteristics and surgical history that suggest MPS disorders and refer such patients to geneticists for evaluation before surgery.

References:
1- Arn P, Wraith JE, Underhill L: Characterization of surgical procedures in patients with mucopolysaccharidosis type I: findings from the MPS I Registry.  J Pediatr. 154(6):859-64.e3, 2009
2- Munoz-Rojas MV, Bay L, Sanchez L, van Kuijck M, Ospina S, Cabello JF, Martins AM: Clinical manifestations and treatment of mucopolysaccharidosis type I patients in Latin America as compared with the rest of the world. J Inherit Metab Dis. 34(5):1029-37, 2011
3- Osthaus WA, Harendza T, Witt LH, et al: Paediatric airway management in mucopolysaccharidosis 1: a retrospective case review. Eur J Anaesthesiol. 29(4):204-7, 2012
4- Arn P, Whitley C, Wraith JE, Webb HW, Underhill L, Rangachari L, Cox GF: High rate of postoperative mortality in patients with mucopolysaccharidosis I: findings from the MPS I Registry. J Pediatr Surg. 47(3):477-84, 2012
5- Kirkpatrick K, Ellwood J, Walker RW: Mucopolysaccharidosis type I (Hurler syndrome) and anesthesia: the impact of bone marrow transplantation, enzyme replacement therapy, and fiberoptic intubation on  airway management. Paediatr Anaesth. 22(8):745-51, 2012
6- Leboulanger N, Louis B, Fauroux B: The acoustic reflection method for the assessment of paediatric upper airways. Paediatr Respir Rev. 2013 May 13


Trichilemmal Cyst

Cystic lesions of the skin in children are fairly common. Most cases are either sebaceous or pilomatrixoma cysts. Cysts where keratinization occurs without keratohyaline granules derived from the follicular isthmus of the external root sheath of the hair follicle are called trichilemmal or pillar cysts. Trichilemmal cysts occur most commonly in the scalp due to the dense hair follicle concentration. Face, trunks, back and forehead are the other common site in that order. Trichilemmal cysts can occur as sporadic lesions or in hereditary-familial settings with autosomal dominant transmission. Though almost always benign, malignant transformation can occur rarely. They may be locally aggressive becoming large and ulcerated. Proliferating trichilemmal tumor is a solid cystic neoplasm that shows differentiation similar to that of the isthmus of the hair follicle. Trichilemmal cysts are usually a solitary intradermal or subcutaneous lesions. The cyst is lined by stratified squamous epithelium.  They can grow to large sizes. Management of trichilemmal cyst consists of surgical excision. The cytologic diagnosis of pilar cysts is important because these cysts recur if incompletely excised and often undergo transformation to pilar tumors.

References:
1- Adachi N, Yamashita T, Ito H: Differential diagnosis of scalp trichilemmal cyst on MRI. Dermatology. 193(3):263-5, 1996
2- Shet T, Rege J, Naik L: Cytodiagnosis of simple and proliferating trichilemmal cysts. Acta Cytol. 45(4):582-8, 2001
3- Nakamura M, Toyoda M, Kagoura M, Higaki S, Morohashi M: Ultrastructural characteristics of trichilemmal cysts: report of two cases. Med Electron Microsc. 34(2):134-41, 2001
4- Garg PK, Dangi A, Khurana N, Hadke NS: Malignant proliferating trichilemmal cyst: a case report with review of literature. Malays J Pathol. 31(1):71-6, 2009
5- Ibrahim AE, Barikian A, Janom H, Kaddoura I: Numerous recurrent trichilemmal cysts of the scalp: differential diagnosis and surgical management. J Craniofac Surg. 23(2):e164-8, 2012
6- Seidenari S, Pellacani G, Nasti S, Tomasi A, Pastorino L, Ghiorzo P, Ruini C, Bianchi-Scarrà G, Pollio A, Mandel VD, Ponti G: Hereditary trichilemmal cysts: a proposal for the assessment of diagnostic clinical criteria. Clin Genet. 84(1):65-9, 2013


PSU Volume 41 NO 06 NOVEMBER 2013

Atrophic Testis

Atrophic testes refer to a testis that has diminished in size and is accompanied by loss of function.  An atrophic testis can be the result of perinatal torsion, cryptorchidism, trauma, previous surgical procedure, orchitis and steroid use. Most atrophic testes are abnormal due to a mechanical event shunting circulation rather than maldevelopment or iatrogenic. Anabolic steroids can cause testicular atrophy by reducing the amount of luteinizing hormone produced by the pituitary gland. Repair of inguinal hernia after incarceration can also cause testicular atrophy if vascular testicular occlusion occurred for en extended period of time. Testicular atrophy can occur in almost 50% of cases of non-palpable undescended testes. During perinatal descent the testis circulation is entrapped causing the atrophy or vanishing of the testis.  They have sometimes been called vanishing testes since a remnant nubbin is found during inguinal or abdominal exploration. Very few of these remnants contains seminiferous tubules and even fewer shows viable germ cells. Contralateral testicular hypertrophy strongly indicates an atrophic testis in the other side. Ultrasonography can determine the significant smaller size of the affected testis and determine if is hypoechoic, a sonographic characteristic of the atrophic testis. The management of the atrophic testis is controversial. Removal of the remnant and placement of a prothesis is an alternative in children. With growth this prothesis will need replacement, hence placement during final adolescent growth years is more prudent. The risk of malignant degeneration of the testicular remnant is extremely low to justify surgical removal.


References:
1- Wood HM, Elder JS: Cryptorchidism and Testicular Cancer: Separating Fract from Fiction. J Uro 181 (2): 452-461, 2009
2- Antic T, Hyjek EM, Taxy JB: The Vanishing Testis. A histomorphologic and clinical assessment. AM J Clin Pathol. 136: 872-880, 2011
3- Cortes D, Thorup J, Petersen BL: Testicular neoplasia in undescended testes of cryptorchid boys-does surgical strategy have an impact on the risk of invasive testicular neoplasia? Turk J Pediatr. 46 Suppl:35-42, 2004
4- Chu L, Averch TD, Jackman SV: Testicular infarction as a sequela of inguinal hernia repair. Can J Urol. 16(6):4953-4, 2009
5- Shibata Y, Kojima Y, Mizuno K, Nakane A, Kato T, Kamisawa H, Kohri K, Hayashi Y: Optimal cutoff value of contralateral testicular size for prediction of absent testis in Japanese boys with nonpalpable testis. Urology. 76(1):78-81, 2010

6- Vijayaraghavan SB: Sonographic localization of nonpalpable testis: Tracking the cord technique. Indian J Radiol Imaging. 21(2):134-41, 2011


Tension Gastrothorax

The term tension gastrothorax originally appeared in the literature as a complication of traumatic rupture of the diaphragm producing mediastinal shift due to a distended intrathoracic stomach. Congenital or acquired diaphragmatic defects can cause a tension pneumothorax. The two groups of children that can be affected by a tension gastrothorax include those with congenital diaphragmatic hernia with late presentation and traumatic diaphragmatic hernias the result of a previous accident. Most cases of tension gastrothorax occur around the five years of age  in cases with an existing congenital defect. Vast majority are left-sided because the liver buttresses the right side. Increased intraabdominal pressure or negative intrathoracic pressure leads to herniation of the stomach into the chest. Respiratory symptoms initially followed by abdominal pain and vomiting develops. Other findings are tracheal deviation, reduced breaths sound, dullness or resonance and a displace cardiac apex. Tension gastrothorax can be erroneously interpreted as a tension pneumothorax leading to increase morbidity and mortality during treatment. The chest film can be diagnostic demonstrating a large air-filled structure with or without a fluid level within the left hemithorax causing apical collapse of the lung. Emergency management requires initial decompression with a large-bore nasogastric tube. If this fails transthoracic needle decompression of the stomach can be tried. Urgent definitive management requires surgical reduction of the intrathoracic stomach and repair of the diaphragmatic defect which can be accomplished preferably by laparotomy as it hasten quick reduction of stomach and repair of the diaphragmatic defect. Thoracotomy or thoracoscopy has also been utilized less frequently. Morbidity relates to pulmonary collapse, shock, bowel injury and sepsis due to gastric perforation in the thorax.


References:
1- Rathinam S, Margabanthu G, Jothivel G, Bavanisanker T: Tension gastrothorax causing cardiac arrest in a child. Interact Cardiovasc Thorac Surg. 1(2):99-101, 2002
2- Zedan M, El-Ghazaly M, Fouda A, El-Bayoumi M: Tension gastrothorax: a case report and review of literature. J Pediatr Surg. 43(4):740-3, 2008
3- Salim F, Ramesh V: Tension gastrothorax: a rare complication. J Coll Physicians Surg Pak. 19(5):325-6, 2009
4-Hooker R, Claudius I, Truong A: Tension gastrothorax in a child presenting with abdominal pain. West J Emerg Med. 13(1):117-8, 2012
5- Gagg JW, Savva A: Tension gastrothorax: a rare cause of breathlessness. Emerg Med J. 30(6):500, 2013
6- Ng J, Rex D, Sudhakaran N, Okoye B, Mukhtar Z: Tension gastrothorax in children: Introducing a management algorithm. J Pediatr Surg. 48(7):1613-7, 2013

Adrenalectomy in Wilms Tumor

Wilms tumor or nephroblastoma is the most common intraabdominal malignant solid tumor in children. It is managed with surgery, adjuvant chemotherapy and radiotherapy. Surgical management consists of radical nephrectomy when appropriate in many cases removing the adrenal gland concomitantly with the tumor. Adrenal involvement in patients with Wilms tumor is rare and difficult to predict. The decision to remove the ipsilateral adrenal gland has been left to the judgement of the operating surgeon at the time of nephrectomy, and is likely based on the size and location of the primary tumor, ease of adrenalectomy, and suspicion for adrenal involvement Routine adrenalectomy does not confer a benefit for oncologic control (event free survival) when it is feasible to spare the adrenal gland. Intraoperative tumor spillage rates are higher in patients undergoing concomitant adrenalectomy. Patients in whom adrenalectomy was performed tended to have larger tumors than those in whom the gland was left in situ. The histopathologic status of the adrenal gland with tumor does not directly affect the oncologic outcome. Based on the low rate of adrenal involvement, and lack of apparent oncologic benefit to adrenalectomy concurrent with nephrectomy routine adrenalectomy does not appear to be mandatory. Preserving the adrenal gland was not associated with an increased risk of local recurrence. The above appears to hold truth to renal cell carcinoma management in adults.


References:
1- Yap SA, Alibhai SM, Abouassaly R, Timilshina N, Finelli A: Do we continue to unnecessarily perform ipsilateral adrenalectomy at the time of  radical nephrectomy? A population based study. J Urol. 187(2):398-404, 2012
2- Gow KW, Barnhart DC, Hamilton TE, Kandel JJ, Chen MK, Ferrer FA, Price MR, Mullen EA, Geller JI, Gratias EJ, Rosen N, Khanna G, Naranjo A, Ritchey ML, Grundy PE, Dome JS, Ehrlich PF: Primary nephrectomy and intraoperative tumor spill: report from the Children's Oncology Group (COG) renal tumors committee. J Pediatr Surg. 48(1):34-8, 2013
3- Tsui KH, Shvarts O, Barbaric Z, Figlin R, de Kernion JB, Belldegrun A: Is adrenalectomy a necessary component of radical nephrectomy? UCLA experience with 511 radical nephrectomies.  J Urol. 163(2):437-41, 2000
4- Moore K, Leslie B, Salle JL, Braga LH, Bägli DJ, Bolduc S, Lorenzo AJ: Can we spare removing the adrenal gland at radical nephrectomy in children with wilms tumor?  J Urol. 184(4 Suppl):1638-43, 2010
5- Kieran K, Anderson JR, Dome JS, Ehrlich PF, Ritchey ML, Shamberger RC, Perlman EJ, Green DM, Davidoff AM: Is adrenalectomy necessary during unilateral nephrectomy for Wilms Tumor? A report from the Children's Oncology Group. J Pediatr Surg. 48(7):1598-603, 2013
6- Green DM: The evolution of treatment for Wilms tumor. J Pediatr Surg. (48): 14-19, 2013


PSU Volume 41 No 06 DECEMBER 2013

Granular Cell Tumor

Granular cell tumor, also known as Abrikossoff tumor, is a very infrequent benign neoplasm affecting all parts of the body, but with a predilection for the head and neck region. In the head and neck region most cases are localized in the oral cavity, especially the tongue. Granular cell tumor (GCT) is twice as common in females as in males. These tumors usually present as a solitary slow-growing ulcerated nodular mass located mainly in the subcutaneous tissue. The lesion is mobile and not painful with mild pruritus. Multiple development of granular cell tumor can be seen associated with Noonan syndrome and Neurofibromatosis. In children, the most frequent presentation of GCT is congenital epulis, arising from the median ridge of the newborn maxilla. The histogenesis of the tumor is from neural or nerve sheath cells. Histopathology of the tumor shows polygonal cells arranged in sheets with granular eosinophil cytoplasm and small nuclei. The granularity of the tumor cells is due to accumulation of secondary lysosome in the cytoplasm of the cells. An aggressive malignant variant of granular cell tumor is extremely rare. There are no well-defined criteria for the diagnosis of malignancy. Tumor size > 5 cm, rapid growth, vascular invasion, necrosis and cell spindling are important indicators of atypia pertaining malignancy. Occurrence of metastasis is the only accepted criteria of malignancy. Malignancy when present is associated with a poor prognosis. Management of granular cell tumor consists of complete surgical excision. Recurrence is uncommon unless surgical excision has been incomplete. Follow-up must be prolonged.

References:
1- Finck C, Moront M, Newton C, Timmapuri S, Lyons J, Rozans M, de Chadarevian JP, Halligan G: Pediatric granular cell tumor of the tracheobronchial tree. J Pediatr Surg. 43(3):568-70, 2008 2- Dupuis C, Coard KC: A review of granular cell tumours at the University Hospital of the West Indies:  1965-2006. West Indian Med J. 58(2):138-41, 2009
3- Ramaswamy PV, Storm CA, Filiano JJ, Dinulos JG: Multiple granular cell tumors in a child with Noonan syndrome. Pediatr Dermatol. 27(2):209-11, 2010
4- Torre M, Yankovic F, Herrera O, Borel C, Latorre JJ, Aguilar P, Varela P: Granular cell tumor mimicking a subglottic hemangioma. J Pediatr Surg. 45(12):e9-11, 2010
5- Nasser H, Ahmed Y, Szpunar SM, Kowalski PJ: Malignant granular cell tumor: a look into the diagnostic criteria. Pathol Res Pract. 207(3):164-8, 2011
6- Lahmam Bennani Z, Boussofara L, Saidi W, Bayou F, Ghariani N, Belajouza C, Sriha  B, Denguezli M, Nouira R: [Childhood cutaneous Abrikossoff tumor]. Arch Pediatr. 18(7):778-82, 2011

Watersport Injuries

Injuries related to personal watercraft have increased dramatically over the past several years, becoming one of the leading causes of recreational watersport injuries. Median age of the accident is generally 10 years. Towed tubing which involves riding an inflatable tube while being pulled behind a boat is the most prevalent trauma mechanism in watersport injury. This is followed by accidents involving motorboats and accidents involving a personal watercraft. Towed tubing accidents has a longer hospital stay since this mechanism account for an increased morbidity in comparison with other recreational activities. It is strongly suggested that wearing protective gear and protective wet suit should be recommended for children involved in watercraft and watersport activities. Mandatory speed limit regulations should be considered to decrease the risk of serious injury due to the specific category of the watercraft injury. Propeller injuries can produce an increase incidence of distal limb amputations. Almost 20% of all boating fatalities and 8% of all non-fatal injuries are associated with accidents in which alcohol or drugs were contributing factors. Jet ski accidents tended to result in more serious injuries (closed-head injuries, hollow and solid viscus injuries, chest trauma, spinal injuries leading to paralysis, and death) than those sustained in accidents with small boats. It is also recommended life vest and easily visible personal floating devices be used by children and adolescent riding watercrafts. Increased use of personal floating device, avoidance of dangerous currents, and less alcohol use by operators and passengers of all types of watercraft would result in a reduction in watercraft-related drowning. Government statistics on personal watercraft injuries do not accurately reflect the true incidence and economic impact of such trauma. Mandatory educational programs and increased legislation to improve personal watercraft safety should be promoted.


References:
1- Browne ML, Lewis-Michl EL, Stark AD: Watercraft-related drownings among New York State residents, 1988-1994. Public Health Rep. 118(5):459-63, 2003
2- Kim CW, Smith JM, Lee A, Hoyt DB, Kennedy F, Newton PO, Meyer RS: Personal watercraft injuries: 62 patients admitted to the San Diego County trauma services. J Orthop Trauma. 17(8):571-3, 2003
3- Rubin LE, Stein PB, DiScala C, Grottkau BE: Pediatric trauma caused by personal watercraft: a ten-year retrospective. J Pediatr Surg. 38(10):1525-9, 2003
4- White MW, Cheatham ML: The underestimated impact of personal watercraft injuries. Am Surg. 65(9):865-9, 1999
5- Beierle EA, Chen MK, Langham MR Jr, Kays DW, Talbert JL: Small watercraft injuries in children. Am Surg. 68(6):535-8, 2002
6- Keijzer R, Smith GF, Georgeson KE, Muensterer OJ: Watercraft and watersport injuries in children: trauma mechanisms and proposed prevention strategies.  J Pediatr Surg. 48(8):1757-61, 2013

Stuck Catheter

Totally implantable venous access devices are essential for providing therapy for children with cancer, long-term medication,  parenteral nutrition and sampling. Unfortunately they are no without complications during insertion, maintenance and removal. Removal occurs with resolution of disease, dysfunction or infection of the device. One of the most feared complications during removal is the stuck catheter. The catheter after a prolonged period of use is fixed to the vessel wall. The catheter is stuck in strong connective fibrous tissue matrix to the vessel wall. This occurs more commonly with polyurethane catheter than silicone catheters. In fact polyurethane catheters are contraindicated if its going to be in use for more than 18 months. The management of a stuck catheter should follow a course of action encompassing dissection along the subcutaneous tract until the entrance to the vein is encountered. A stiff guide wire can be inserted into the lumen of the catheter and instead of applying a "pull-out" force, use a "push-in" force to detach the catheter from the deep central vein. When the forced "pull-out" maneuver is used, the catheter can stretch and will likely break if the tension exceeds the tolerance of the catheter. The soft J tip of the guide-wire prevents puncture of the catheter or the wall of the heart and vein during the maneuver In other occasion the catheter will brake during removal and either stay stuck in the vein or embolize. In such situation endovascular retrieval by interventional radiologist of the segment of left catheter is indicated due to the inherent risk of infection and venous thrombosis. Have found useful after passing the wire to the stuck catheter cleaning the adherence of fibrin reintroducing a new sheath through the catheter fluoroscopically-guided.


References:
1- Wilson GJ, van Noesel MM, Hop WC, van de Ven C: The catheter is stuck: complications experienced during removal of a totally implantable venous access device. A single-center study in 200 children. J Pediatr Surg. 41(10):1694-8, 2006
2- Field M, Pugh J, Asquith J, Davies S, Pherwani AD: A stuck hemodialysis central venous catheter. J Vasc Access. 9(4):301-3, 2008
3- Huang SC, Tsai MS, Lai HS: A new technique to remove a "stuck" totally implantable venous access catheter. J Pediatr Surg. 44(7):1465-7, 2009
4- Mortensen A, Afshari A, Henneberg SW, Hansen MA: Stuck long-term indwelling central venous catheters in adolescents: three cases and a short topical review. Acta Anaesthesiol Scand. 54(6):777-80, 2010
5- Hong JH: A breakthrough technique for the removal of a hemodialysis catheter stuck in the  central vein: endoluminal balloon dilatation of the stuck catheter.  J Vasc Access. 12(4):381-4, 2011
6- Ryan SE, Hadziomerovic A, Aquino J, Cunningham I, O'Kelly K, Rasuli P: Endoluminal dilation technique to remove "stuck" tunneled hemodialysis catheters. J Vasc Interv Radiol. 23(8):1089-93, 2012




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