[The investigation of blood cells of middle and old age in patients with bronchial asthma and chronic obstructive pulmonary disease by atomic force microscopy. Similarities and differences with the biological animal model].

The investigation of reactive changes of blood cells in such diseases as COPD or asthma in people of different age groups is the very difficult problem. Simulating the same conditions in animals that occur in humans with these diseases can serve as a reliable practical model. It is possible because the changes which take places at the cellular level in animals might reflect a similar trend in the human body.

Being small for gestational age is not an independent risk factor for mortality in neonates with congenital diaphragmatic hernia: a multicenter study.

BACKGROUND: Congenital diaphragmatic hernia (CDH) accounts for 8% of all major congenital anomalies. Neonates who are small for gestational age (SGA) generally have a poorer prognosis. We sought to identify risk factors and variables associated with outcomes in neonates with CDH who are SGA in comparison to neonates who are appropriate for gestational age (AGA). METHODS: We used the multicenter Diaphragmatic Hernia Research & Exploration Advancing Molecular Science (DHREAMS) study to include neonates enrolled from 2005 to 2019. Chi-squared or Fisher's exact tests were used to compare categorical variables and t tests or Wilcoxon rank sum for continuous variables. Cox model analyzed time to event outcomes and logistic regression analyzed binary outcomes. RESULTS: 589 neonates were examined. Ninety were SGA (15.3%). SGA patients were more likely to be female (p = 0.003), have a left sided CDH (p = 0.05), have additional congenital anomalies and be diagnosed with a genetic syndrome (p < 0.001). On initial single-variable analysis, SGA correlated with higher frequency of death prior to discharge (p < 0.001) and supplemental oxygen requirement at 28 days (p = 0.005). Twice as many SGA patients died before repair (12.2% vs 6.4%, p = 0.04). Using unadjusted Cox model, the risk of death prior to discharge among SGA patients was 1.57 times the risk for AGA patients (p = 0.029). There was no correlation between SGA and need for ECMO, pulmonary hypertensive medication at discharge or oxygen at discharge. After adjusting for confounding variables, SGA no longer correlated with mortality prior to discharge or incidence of unrepaired defects but remained significant for oxygen requirement at 28 days (p = 0.03). CONCLUSION: Infants with CDH who are SGA have worse survival and poorer lung function than AGA infants. However, the outcome of SGA neonates is impacted by other factors including gestational age, genetic syndromes, and particularly congenital anomalies that contribute heavily to their poorer prognosis.

Primary mediastinal masses. A comparison of adult and pediatric populations.

Since 1944 62 pediatric patients with primary cysts and tumors of the mediastinum have been operated on at our institution. We compared this group with 195 adult patients with similar diagnoses who were operated on during this period. Comparisons were made with regard to histologic type, location, presenting symptoms, physical findings, and surgical complications. We found significant increases in the prevalence of lymphoma in adults (41/195 versus 4/62, p < 0.05) and of neurogenic tumors in children (21/62 versus 24/195, p < 0.05). There were no significant differences in the prevalence of thymic tumors (51/195 versus 22/62), germ cell tumors (24/195 versus 4/62), and cysts (32/195 versus 15/62). There was no difference in the prevalence of symptomatic patients (99/195 versus 36/62). The prevalence of malignancy has increased in both groups since 1970 (2/28 versus 16/34 in children, p < 0.01; and 14/56 versus 69/139 in adults, p < 0.05). This is attributed to a rise in the prevalence of malignant neurogenic tumors in children and to an increase in the prevalence of lymphomas in adults. Tumor size, location, and the presence of symptoms were predictive of malignancy in the adult population but not in the pediatric population. No difference existed in mortality and morbidity between the two groups. All three pediatric deaths were directly related to loss of airway control as a result of mass effect from the tumor. Definite differences exist between the adult and pediatric populations with regard to mediastinal tumors. These differences need to be considered carefully when evaluating and planning treatment for a child with a mediastinal mass.

Vascular ring: does magnetic resonance imaging replace angiography?

The records of 21 patients who underwent operation for symptoms attributable to vascular ring were reviewed. The study covered 33 years, 1958 to 1991, and the mean follow-up was 6.8 years. The patients ranged from 7 days to 26 years old with a mean age of 2.9 years. Twenty patients were symptomatic. Symptoms were due to tracheal compression in 16 patients, esophageal compression in 2, and both causes in 2. During the first 30 years, chest roentgenography, barium swallow, and aortography constituted the diagnostic workup in the majority of the patients. During the last 3 years, magnetic resonance imaging replaced aortography. The surgical diagnosis included five variants of vascular ring. The surgical approach consisted of left thoracotomy in 19 patients and right thoracotomy in 2. These 2 had the diagnosis of right aortic arch with posterior left subclavian artery. In both instances, preoperative angiographic data determined the surgical approach. Barium swallow may be sufficient for the diagnosis of vascular ring; however, additional data are useful in determining the surgical approach. Magnetic resonance imaging can yield accurate data without subjecting the patient to the risks associated with angiography.

Does telomerase activity add to the value of fine needle aspirations in evaluating thyroid nodules?

BACKGROUND: Telomerase replaces DNA sequences that are lost with cell division. Increased activity has been documented in malignant cells. Fine needle aspiration (FNA) has a 90% sensitivity for diagnosis of papillary carcinomas, but a specificity of 52%. This often leads to unnecessary surgery. METHODS: Telomeric repeat amplification protocol assays were performed on FNA specimens of thyroid nodules in 19 patients. These results were compared with the surgical pathology using chi-square analysis. RESULTS: There were 5 malignant and 14 benign nodules. Telomerase activity was found in 3 of 5 malignant (60%) and 9 of 14 benign (64%): sensitivity was 60%, specificity was 36%. CONCLUSION: Telomerase assays did not add any additional information to FNA alone. Inflammatory changes associated with benign and malignant lesions can possess telomerase activity independent of the malignant state.

Preoperative evaluation and general preparation for chest-wall operations.

Chest-wall reconstruction is a major procedure with a risk of life-threatening complications. Accurate preoperative assessment is therefore critical, as it allows detection and treatment of correctable problems and permits the surgeon to individualize postoperative management. Risk factors may be cardiovascular, pulmonary, or nutritional. The guiding principle of planning for the reconstruction is that there must be absolutely no tension at the site of the full-thickness defect in the chest wall.

Mucoepidermoid carcinoma of the thyroid gland: a case report and suggested surgical approach.

Mucoepidermoid carcinoma (MEC) of the thyroid gland is a rare neoplasm with 40 cases reported in the world literature to date. Controversy surrounds the treatment of this rare neoplasm. It has been described as a low-grade indolent tumor that rarely metastasizes and only recurs locally without morbidity. Suggested treatment has consisted of a lobectomy or subtotal thyroidectomy. We report a case of a 63-year-old woman with a 15-year history of a multinodular goiter with a dominant left lobe nodule. Fine-needle aspiration was inconclusive. The patient opted for a total thyroidectomy. Final pathology yielded a diagnosis of mucoepidermoid carcinoma. We propose that despite its low-grade appearance the morbidity and mortality associated with its ability to locally recur and metastasize justify the need for more aggressive surgical therapy.

Effect of the Palmaz balloon-expandable metallic stent in the trachea of pigs.

Endoscopically placed airway stents offer a viable option in primary or adjunctive treatment of severe pediatric tracheobronchial stenoses. Optimistic clinical reports substantiate the need for experimental studies to more effectively evaluate their clinical role. Development of an animal model comparable with the pediatric airway, amenable to endoscopic instrumentation, and capable of assessing effect on growth was the purpose of this pilot project. Nine 4-week-old piglets underwent endoscopic midtracheal placement of the balloon-expandable Palmaz metallic stent. Initial expansion and stent position were verified fluoroscopically and by direct videobronchoscopy. Serial endoscopic examination and stent reexpansion were performed 2 and 4 weeks after stent insertion. Animal weight, clinical tolerance, tracheal growth, and stent integrity were observed. Tracheal inflammation was evaluated grossly and by objective histopathologic criteria. Successful endotracheal stent placement and expansion were accomplished in all piglets. One pig died of anesthesia complications less than 24 hours after stent insertion. The remaining pigs exhibited excellent clinical tolerance through experiment completion. No detrimental effect on growth was noted, and effective dilatation of the stented tracheal region was observed. Stent incorporation was evident with significant mucosal ingrowth. Inflammation in the form of nonobstructing granulation tissue was present, and no evidence of necrosis or cartilage invasion was evident. The piglet trachea appears to be an excellent model for evaluation of expandable metallic airway stents in management of congenital and acquired tracheobronchial stenoses.

A 45-year experience with surgical treatment of peptic ulcer disease in children.

Peptic ulcer disease (PUD) requiring surgical treatment has become rare with the availability of modern medical management. A retrospective study of all patients who required operations for PUD between 1949 and 1994 (n = 43) was done. The patients were classified into 3 groups: A (n = 38): pre-histamine-2 (H2) blocker era (1949-1975); B (n = 3): pre-hydrogen-potassium (H-K+) ATPase inhibitor era (1976-1988); C (n = 2): H-K+ ATPase inhibitor era (1989-1994). Data, analyzed using X2 analysis (P < .01), included preoperative medical therapy, surgical indications, type of operation performed, complications, and postoperative medical therapy. The indication for surgery in group A was bleeding (26), perforation (8), or obstruction (4); in group B the indication was obstruction (2) or perforation (1); in group C the indication was obstruction (1) or bleeding (1). The incidence of obstruction as an indication for surgery did not differ among the groups (P < .01). Two of the three patients who had surgery for obstruction in groups B and C had biopsy-proven Helicobacter pylori. The postoperative morbidity rate was lower for groups B and C, although not significantly. The relative mortality among the groups did not change (P > .01). Children with PUD can have complications similar to those of adults with PUD. Since the introduction of H2 antagonists, the recognition and treatment of H pylori, and the use of H-K+ ATPase inhibition, the incidence of operations for bleeding and perforation has decreased dramatically. However, the incidence of surgery for obstruction remains the same.

The impact of a previous Kasai procedure on liver transplantation for biliary atresia.

The usual treatment for biliary atresia is a Kasai procedure followed by liver transplantation when indicated. Although primary transplantation for biliary atresia without a previous Kasai procedure is occasionally advocated, it is rarely performed. This review was undertaken to evaluate the impact of a Kasai procedure on the morbidity and mortality of patients who went on to need a liver transplant. Sixty-three patients with biliary atresia were included in this review. Fifty seven patients underwent transplantation: eight patients had a liver transplant only (group 1), and 49 patients underwent a Kasai procedure before transplantation (group 2). Six patients died before receiving a transplant. Time spent on the waiting list for liver transplant was longer in group 2 than in group 1 (170.3 +/- 24.6 days versus 63.3 +/- 7.1 days, P < .05). The patients in group 1 were younger (0.7 +/- 0.2 versus 2.3 +/- 0.4 years) and smaller (6.9 +/- 0.4 kg versus 11.6 +/- 1.2 kg) than the patients in group 2 (P = .07). There was no difference in pretransplant urgency status between the two groups. The mean duration of the transplant operation was shorter in group 1 patients (476.8 +/- 53.3 minutes) compared with group 2 (593.9 +/- 29.3 minutes, P = .06). Group 1 patients received 199.8 +/- 46.2 mL/kg blood transfusion intraoperatively, and group 2 patients had twice that amount, 466 +/- 122.5 mL/kg. No patients in group 1 experienced postoperative bowel perforations or required reoperation for bleeding. In group 2 however, 11 of 49 (22.4%) experienced bowel perforations and 7 of 49 (14.2%) required reoperation for bleeding. There was no difference in nonsurgical complications between the two groups. Long-term survival was equal in the 2 groups: six of eight patients (75%) in group 1 and 36 of 49 (74%) in group 2. The marked increase in complications noted in group 2 patients did not reach statistical significance because of the much smaller number of patients in group 1. These results suggest that patients with biliary atresia have fewer complications after transplantation if a Kasai procedure is not performed before the transplant, and that a more careful selection of surgical options available in treating patients with biliary atresia is required.

Extrauterine twin-twin transfusion affects renal function and perioperative management of conjoined twins.

This series describes the occurrence of unbalanced circulatory shunting in three consecutively treated pairs of conjoined twins. The impact of renal functional changes and compensatory cardiac physiology on the timing of surgery and perioperative management are illustrated. The craniopagus set of twins presented in renal failure (1A) and cardiac failure (1B) to our hospital at age 2.5 years. Renal transplantation for anuria was performed in 1A before separation of the twins. This did not improve urine output in the hypoperfused twin, and normal renal function was not restored until the twins were separated. Two sets of omphalopagus twins were delivered and transferred to our hospital and separated during the first week of life. In each case a preoperative oliguric state in the underperfused twin reversed after separation, and a postoliguric diuresis ensued. Serum creatinine levels were similar in each pair preoperatively despite the inequality in urine volumes. In conjoined twins, assessment of renal function is necessary and should include serial measurements of urine volumes and urine creatinine clearance. Serum creatinine is not a useful marker of individual twin renal function in this situation. When disparity in renal function exists, early separation is indicated to prevent renal failure and compensatory cardiac failure.

Congenital thymic cysts in children--mostly misdiagnosed.

BACKGROUND/PURPOSE: Thymic cysts are rare lesions of the neck and mediastinum that are difficult to diagnose. Often considered inconsequential, these lesions can frequently be symptomatic. In this report the authors contrast their experience with that of the literature. METHODS: From 1984 through 1997, the authors encountered 14 patients with this lesion. All cysts were completely excised. Patients that had an acquired cyst of the thymus were excluded from this series. RESULTS: Of the 14 patients ranging in age from 2 weeks to 16 years, seven patients had cervical masses, five had mediastinal masses, and two children had both sites involved. Seven children were symptomatic with wheezing and upper respiratory infection, with cough and fever being the most common clinical features. Investigations included chest radiograph, contrast esophagram, sonography (US) and computerized tomography (CT). Displacement of vital mediastinal or neck structures was observed in eight patients. Only two patients received correct diagnosis before surgery. Successful and complete excision of all cysts was achieved. The cysts were benign and ranged in size from 2 to 22 cm in diameter. CONCLUSION: Often forgotten, thymic cysts are rare benign lesions that should be considered in the differential diagnosis of cervical and mediastinal masses in children.

Biliary atresia: should all patients undergo a portoenterostomy?

PURPOSE: The management of noncorrectable extra hepatic biliary atresia includes portoenterostomy, although the results of the surgery are variable. This study was done to develop criteria that could successfully predict the outcome of surgery based on preoperative data, including percutaneous liver biopsy, allowing a more selective approach to the care of these babies. METHODS: The charts and biopsy results of 31 patients who underwent a Kasai procedure for biliary atresia between 1984 and 1994 were reviewed. Values for preoperative albumin, bilirubin, age of patient at Kasai, and lowest postoperative bilirubin were recorded. Surgical success was defined as postoperative bilirubin that returned to normal. A pathologist blinded to the child's eventual outcome graded the pre-Kasai needle liver biopsy results according to duct proliferation, ductal plate lesion, bile in ducts, lobular inflammation, giant cells, syncitial giant cells, focal necrosis, bridging necrosis, hepatocyte ballooning, bile in zone 1, 2, and 3, cholangitis, and end-stage cirrhosis. Clinical outcome was then predicted. RESULTS: Success after portoenterostomy could not reliably be predicted based on gender, age at Kasai, preoperative bilirubin or albumin levels. Histological criteria, however, predicted outcome in 27 of 31 patients (P < .01). Fifteen of 17 clinical successes were correctly predicted; as were 12 of 14 clinical failures (sensitivity, 86%; specificity, 88%). Individually, the presence of syncitial giant cells, lobular inflammation, focal necrosis, bridging necrosis, and cholangitis, were each associated with failure of the portoenterostomy (P < .05). Bile in zone 1 was associated with clinical success of the procedure (P < .05). CONCLUSIONS: Based on the predictive information available in a liver biopsy, we conclude that those patients who will not benefit from a Kasai procedure can be identified preoperatively, and channeled immediately to transplantation.

Congenital diaphragmatic hernia--a tale of two cities: the Toronto experience.

PURPOSE: The optimal therapy for congenital diaphragmatic hernia (CDH) is evolving. This study analyzes the results of treatment of CDH in a large tertiary care pediatric center using conventional and high-frequency oscillatory ventilation (HFOV) without extracorporeal membrane oxygenation (ECMO) contrasting these with a parallel study from a similar large urban center using conventional ventilation with ECMO. METHODS: Between 1981 and 1994, 223 consecutive neonates who had CDH diagnosed in the first 12 hours of life were referred for treatment before repair. Conventional ventilation was used with conversion to HFOV for refractory hypoxemia or hypercapnia, and a predicted near 100% mortality rate. ECMO was used in only three patients, all of whom died. A retrospective database was collected. Thirty-one clinical variables were tested for their association with the outcome. Common ventilatory and oxygenation indices were tested for their prognostic capability. RESULTS: Apgar scores, birth weight, right-sided defects, pneumothorax, total ventilatory time, and the use of high frequency oscillatory ventilation were the only variables associated with outcome. A modified ventilatory index and postductal A-aDo2 were strong prognostic indicators. From 1981 to 1984 surgery was performed on an emergency basis. Since 1985 surgery was deferred until stabilization had been achieved. This resulted in a shift in the mortality from postoperative to preoperative with no change in total survival. HFOV did not alter the overall survival. Results of autopsies performed (70%) showed significant pulmonary hypoplasia and barotrauma as the primary causes of death. The survival was 54.7%. CONCLUSION: Conventional ventilation with HFOV produced equal survival to conventional ventilation with ECMO in two comparable series. Pulmonary hypoplasia was the principle cause of death. This continued high mortality at both centers suggests that new therapies are required to improve outcomes.

Pulmonary barotrauma in congenital diaphragmatic hernia: a clinicopathological correlation.

BACKGROUND/PURPOSE: The high mortality rate in congenital diaphragmatic hernia (CDH) has been ascribed to pulmonary hypoplasia and persistent pulmonary hypertension of the newborn (PPHN). One of the principal treatment strategies has been the use of hyperventilation to reverse ductal shunting, but the wisdom of this approach is being questioned because of parenchymal lung injury from high inflation pressures. The authors hypothesize that the use of hyperventilation to reverse or prevent ductal shunting would result in ventilator-induced lung injury, which would be evident on postmortem examination. A retrospective review of clinical and autopsy information was conducted. METHODS: Clinical and autopsy information gathered for a previously published series of 223 infants with CDH presenting in the first 24 hours of life was reviewed. Autopsy and clinical data were analyzed from 68 of 101 nonsurvivors who died with severe hypoxemia. RESULTS: Sixty-two of 68 cases (91%) had evidence of diffuse alveolar damage and hyaline membrane formation, which was more evident in the ipsilateral lung. Forty-four (65%) infants had pneumothoraces, and 4 infants had interstitial fibrosis. Pulmonary hemorrhage was seen in 35 cases (50 maximum peak inspiratory pressure [mean +/- SD] was 40.4+/-7.9 cm H2O and lowest modified ventilatory index [respiratory rate x peak airway pressure] was 2323+/-836). The degree of pulmonary hypoplasia was evaluated by lung weight with the ratio of the observed combined lung weight to the expected lung weight based on birth weight and gestational age. The ratio based on birth weight was 57%+/-25%, and the ratio based on gestational age was 60%+/-26%. Twenty-one infants (35%) had nonpulmonary anomalies. The most significant was a 10% incidence of congenital heart disease. Apart from this, lethal nonpulmonary anomalies were rare. CONCLUSION: These results suggest that lung injury secondary to mechanical ventilation plays an important role in the mortality rate of patients with CDH, which may become increasingly significant when there is underlying pulmonary hypoplasia.

Trauma experience comparison of army forward surgical team surgeons at Ben Taub Hospital and Madigan Army Medical Center(2)(2).

Far forward life-saving surgical care is the mission of an army forward surgical team (FST). Trauma skill maintenance is necessary to complete that mission. A new program has been developed for FST training using the resources of a Level 1 trauma center. We sought to compare the experience of FST surgeons at a major urban trauma center with the yearly trauma experience at an army Level 2 trauma center.General surgeons of the 250th FST prospectively tabulated data for trauma patients during a September 1999 unit deployment to Ben Taub Hospital (Houston, Texas). Data collected included nature and location of injury, hospital admission, and surgical intervention. During 1999, similar data were collected at Madigan Army Medical Center (MAMC) (Ft. Lewis, Washington), home station of the 250th and Level 2 trauma center since November 1998.The FST general surgeons observed 319 injuries. Of those injured, 104 were admitted and 19 underwent urgent operation. Direct participation by FST general surgeons in the operative procedures varied. In 1999, MAMC general surgeons treated 455 trauma victims in direct supervision of Army general surgery residents. Madigan Army Medical Center general surgeons admitted 304 and urgently operated on 57 trauma patients, while 107 patients were transferred to another institution for definitive management of orthopedic and nonoperative neurosurgical injuries.CONCLUSIONS:The volume of trauma surgical cases at MAMC during 1999 was 3 times that seen in the 1-month rotation at Ben Taub. General surgeons performed more trauma and abdominal surgery at MAMC with significantly more direct involvement in patient care and operative procedures. The experience of the 250th FST does not justify trauma sustainment deployments for surgeons from military trauma centers.

Gastrin-releasing peptide: a potential growth factor expressed in human neuroblastoma tumors(1).

PURPOSE:Gastrin-releasing peptide (GRP) is a 27-amino acid neuropeptide that has been identified in the cytoplasm of many neuroendocrine tumors. Gastrin releasing peptide has been labeled as an autocrine growth factor in small cell lung carcinomas. Recent work has also shown this to be true in the growth of neuroblastoma cells in vitro. The purpose of this study was to demonstrate GRP and its receptor (GRP-R) in resected human neuroblastomas and to correlate the presence or absence with other known predictors of poor prognosis.To demonstrate the presence of GRP and GRP-R mRNA, total RNA was extracted from human neuroblastoma cells. A reverse transcription-polymerase chain reaction (RT-PCR) was then performed using specific primers. The products of the RT-PCR were then confirmed to be GRP and GRP-R cDNA by Southern blot analysis. The RT-PCR products were then sequenced, and these sequences were compared with the know sequences of GRP and GRP-R DNA.N = 19. GRP and GRP-R mRNA were present in all neuroblastoma specimens. Although no correlation with other known predictors of poor prognosis existed, transcripts of four different sizes (400, 450, 500, and 950 bp) were seen in the GRP-R transcripts. The sequences of the 950 bp-sized transcript reverse transcription PCR products were identical to the known GRP-R.We conclude that gastrin releasing peptide and gastrin releasing peptide receptor mRNA are present in all human neuroblastomas. Although qualitatively it appears to lack prognostic significance, its ubiquitous nature in the tumor suggests it may be a useful target on which to base future treatment modalities.

Bioabsorption qualities of chitosan-absorbable vascular templates(1).

PURPOSE:The scope of endovascular surgical techniques has expanded to include the treatment of diseases considered at one time to be amenable only to surgical treatment. The development of the biodegradable template follows as an extension of current permanent stent technology. The goal of our project is to develop and test chitosan as an absorbable template for the vascular system.Ultrapure chitosan, heparin sodium salt and lysozyme, and contrast agents MD-76R and Oxilan-350 were used to give radioopaque quality. Prototype chitosan vascular templates were obtained by a dip coating method in which alternate layers of chitosan were coagulated with nonsolvents or heparin. The amount of loaded and released heparin was determined using Azure II colorimetric assay. In vitro enzymatic degradation of templates was evaluated using lysozyme solutions in phosphate buffered saline. Mechanical properties were analyzed using the Dynamic Mechanical Analyzer, DMA-7 (Perkin Elmer, Foster City, Calif.). The microstructure of freeze-dried templates was investigated by field emission scanning electron microscopy (FE SEM) using an LEO 982 electron microscope (Zeiss, Thornwood, NY).In vivo deployment of the templates was undertaken in 10 full-sized pigs (Sus scrofa). After open expose and control of the iliac artery, a closed balloon catheter technique was used to advance and place the balloon catheter and template. The balloon was then expanded, deploying a Palmaz stent with a chitosan template anchored distally. Patency and deployment of the stent-template complex was confirmed by an arteriogram. The animals were sacrificed at 1, 2, 3, 4, and 5 weeks poststent placement, and arterial sections were taken for microscopic analysis. The amount of chitosan remaining was estimated to determine an in vivo rate of absorption.On hematoxilyn and eosin staining of the section arterial samples, a marked inflammatory response was noted and progressed with duration of in vivo contact. A giant cell foreign body reaction coupled with intense intimal hyperplasia and organized thrombus was also noted and progressed with duration of time in vivo. Also noted was the degradation of the template material with only small remnants of material noted within the giant cell by week 4. Clinically, none of the pigs developed limb ischemia or evidence of thromboembolic events.In this in vivo study, the chitosan template proved to be biodegradable but elicited an intense thrombotic and foreign body reaction despite heparin bonding. Further investigation is ongoing as to decreasing the thrombogenic and antigenic qualities of the template materials by either alteration of the base material or addition of bioactive side chains.

Total colonic manometry as a guide for surgical management of functional colonic obstruction: Preliminary results.

BACKGROUND/PURPOSE: Functional colonic obstruction (pseudo-obstruction) encompasses a broad group of motility disorders. Medical management of colonic pseudo-obstruction is complex and often fails, leading to surgical referral. In most cases (excepting Hirschsprung's disease) the surgeon is unable to precisely localize the area of functional obstruction. Total colonic manometry can directly measure intraluminal pressures and contractile function along the entire length of the colon. The authors propose that total colonic manometry can be used by the pediatric surgeon to guide the timing and extent of surgical therapy in refractory functional colonic obstruction. METHODS: Four patients were evaluated for functional colonic obstruction. All underwent barium enema and rectal biopsy with a diagnosis of Hirschsprung's disease in one patient. All patients underwent colonoscopy and total colonic manometry. Manometric tracings were obtained while fasting, after feeding, and after pharmacologic stimulation both preoperatively (n = 4) and postoperatively (n = 3). RESULTS: Total colonic manometry identified an abrupt end of normal peristalsis in 2 of the non-Hirschsprung's patients (one in the proximal colon and one in the transverse colon). Medical therapy failed in both of these patients, and they underwent diverting ostomy proximal to the loss of normal peristalsis. The third non-Hirschsprung's patient essentially had normal manometry and was able to have her colon decompressed successfully on a laxative regimen. Repeat manometry after colonic decompression showed return of normal peristalsis in 2 of these patients and continued abnormal peristaltic activity in the third. Definitive surgical intervention based on the results of total colonic manometry was performed on the latter. All 3 patients achieved normal continence. A fourth patient had Hirschsprung's disease confirmed by rectal biopsy and underwent a 1-stage neonatal modified Duhamel procedure, which was complicated by postoperative functional obstruction. Manometry showed a lack of peristaltic function beginning in the right colon. An ileostomy was performed, and timing of ileostomy closure was guided by the return of normal colonic peristalsis seen on manometry. CONCLUSIONS: These initial cases show the utility of total colonic manometry in the management of colonic pseudo-obstruction syndromes. In addition to its diagnostic utility, direct measurement of colonic motor activity can be valuable in deciding the need for and timing of diversion, the extent of resection, and the suitability of the patient for restoring bowel continuity. In Hirschsprung's disease, total colonic manometry can potentially be used to determine suitability for primary neonatal pull-through versus a staged approach. J Pediatr Surg 36:1757-1763.

Multidisciplinary evaluation of the distended abdomen in critically ill infants and children: the role of bedside sonography.

Abdominal distention and metabolic acidosis are common in critically ill infants and children, and can be manifestations of an intra-abdominal catastrophe. This series demonstrates the value of bedside sonography (US) in this difficult assessment. Eight infants and children presented with the above situation. Seven were immediately post-cardiopulmonary resuscitation and none had antecedent histories of abdominal pain or bilious vomiting. Abdominal radiographs could not rule out intra-abdominal pathology such as ischemic bowel. Review of all laboratory and radiological data showed US to be a discerning modality for acute bowel pathology. A characteristic pattern of echogenic ascites, thickened bowel wall, dilated, fluid-filled bowel lumen, and lack of peristalsis was seen in those children with gangrenous bowel. Sonographic examination accurately predicted the status of the bowel in all patients. Four patients survived: two had segmental ileal necrosis, one had localized gangrene of the jejunum (twice), and one had necrotic bowel from a closed-loop obstruction. The four who died had malrotation with volvulus (two), superior mesenteric venous thrombosis, and one was immunocompromised with pulmonary aspiration. We conclude that bedside US can be extremely valuable as an adjunct in assessing the abdomen and diagnosing gangrenous bowel in critically ill infants and children.