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Risks of the introduction of highly pathogenic avian influenza (HPAI) H5N1 through migratory birds to the main wintering site for wild birds in southern Brazil and its consequences were assessed. Likelihoods were estimated by a qualitative scale ranging from negligible to high. Northern migrants that breed in Alaska and regularly migrate to South America (primary Charadriiformes) can have contact with birds from affected areas in Asia. The likelihood of the introduction of HPAI H5N1 through migratory birds was found to be very low as it is a probability conditioned to successful transmission in breeding areas and the probabilities of an infected bird migrating and shedding the virus as far as southern Brazil. The probability of wild species becoming exposed to H5N1-infected birds is high as they nest with northern migrants from Alaska, whereas for backyard poultry it is moderate to high depending on proximity to wetlands and the presence of species that could increase the likelihood of contact with wild birds such as domestic duck. The magnitude of the biological and economic consequences of successful transmission to poultry or wild birds would be low to severe depending on the probability of the occurrence of outbreak scenarios described. As a result, the risk estimate is greater than negligible, and HPAI H5N1 prevention strategy in the region should always be carefully considered by the veterinary services in Brazil.

Nutcracker esophagus (NE), Jackhammer esophagus (JHE), distal esophageal spasm (DES), and hypertensive lower esophageal sphincter (HTLES) are defined by esophageal manometric findings. Some patients with these esophageal motility disorders also have abnormal gastroesophageal reflux. It is unclear to what extent these patients' symptoms are caused by the motility disorder, the acid reflux, or both. The aim of this study was to determine the effectiveness of laparoscopic Nissen fundoplication (LNF) on esophageal motility disorders, gastroesophageal reflux, and patient symptoms. Between 2007 and 2013, we performed high-resolution esophageal manometry on 3400 patients, and 221 patients were found to have a spastic esophageal motility disorder. The medical records of these patients were reviewed to determine the manometric abnormality, presence of gastroesophageal symptoms, and amount of esophageal acid exposure. In those patients that underwent LNF, we compared pre- and postoperative esophageal motility, gastroesophageal symptom severity, and esophageal acid exposure. Of the 221 patients with spastic motility disorders, 77 had NE, 2 had JHE, 30 had DES, and 112 had HTLES. The most frequently reported primary and secondary symptoms among all patients were: heartburn and/or regurgitation, 69.2%; respiratory, 39.8%; dysphagia, 35.7%; and chest pain, 22.6%. Of the 221 patients, 192 underwent 24-hour pH monitoring, and 103 demonstrated abnormal distal esophageal acid exposure. Abnormal 24-hour pH monitoring was detected in 62% of patients with heartburn and regurgitation, 49% of patients with respiratory symptoms, 36.8 % of patients with dysphagia, and 32.6% of patients with chest pain. Sixty-six of the 103 patients with abnormal 24-hour pH monitoring underwent LNF. Thirty-eight (13NE, 2JHE, 6 DES, and 17 HTLES) of these 66 patients had a minimum of 6-month postoperative follow-up that included clinical evaluation, esophageal manometry, and 24-hour pH monitoring. Postoperatively, all 38 patients had normal distal esophageal acid exposure. Of these 38 patients, symptoms resolved in 28 and improved in 10. Of six patients (one with NE, two JHE, and three with HTLES) that underwent postoperative esophageal manometry, five exhibited normal motility. Typical reflux symptoms are common among patients with esophageal hypermotility disorders. Abnormal 24-hour pH monitoring is present in the majority of patients with who report typical reflux symptoms and almost half of patients who report respiratory symptoms. Conversely, the majority of patients who report dysphagia or chest pain have normal distal esophageal acid exposure. Based on a small number of patients in this study, it also appears that motility disorders often improve after LNF. LNF is associated with resolution or improvement in reflux related symptoms and esophageal motility parameters in patients exhibiting abnormal esophageal acid exposure. This suggests that patient symptoms are due to abnormal acid exposure and not the motility disorder.

The following on surgical treatments for Barrett's esophagus includes commentaries on the indications for antireflux surgery after medical treatment; the effects of the various procedures on the lower esophageal sphincter; the role of impaired esophageal motility and delayed gastric emptying in the choice of the surgical procedure; indications for associated highly selective vagotomy, duodenal switch, and gastric electrical stimulation; therapeutic strategies for detection and treatment of shortened esophagus; the role of antireflux surgery on the regression of metaplastic mucosa and the risk of malignant progression; the detection of asymptomatic reflux brfore bariatric surgery; the role of non-GERD symptoms on the results of surgery; and the indications of Collis gastroplasty and choice of the type of fundoplication.

Over the past two decades in the Chinese banking system substantial progress has been made, and reforms have been mainly aimed at improving its governance and efficiency, but many governance problems still exist and hinder a complete transition to a market economy. Through the analysis of the economic freedom and the global governance indicators, in the context of a comparative analysis with European and North American countries, this paper shows that, despite a considerable economic growth, economic and financial reforms, Chinese governance variables are likely to have a second order effect in comparison with fundamental economic variables in favouring (or not) Chinese growth. However the high rate of growth, over the years of the financial turmoil as well, may have paradoxically prevented the improvement of governance indexes, meanwhile financial sector and global governance issues will have to be improved in order to promote efficient financial intermediation and sustainable growth in China.

SummaryAlthough the procedures of endoscopic surgery are in many ways, simply a new way of approaching old, familiar problems, certain technical aspects are sufficiently different enough from the common experience of the general surgeon so as to require special training and certification for competency. The introduction of laparoscopic cholecystectomy worldwide showed that many aspects of endoscopic surgery deserved emphasis in training. These include the unique instruments, equipment, and techniques associated with videoendoscopic procedures and, perhaps of even greater importance, the differences in anatomic exposure and perspective afforded by the laparoscope [1–4]. Surgeons used to working in a three-dimensional environment with extensive tactile sensation were forced to learn to operate at a distance from the target tissue using instruments that provided much less feel for the tissues. Direct visualization of the operative field was replaced by a narrow field of view and a magnified, two-dimensional ...

Risks of the introduction of highly pathogenic avian influenza (HPAI) H5N1 through migratory birds to the main wintering site for wild birds in southern Brazil and its consequences were assessed. Likelihoods were estimated by a qualitative scale ranging from negligible to high. Northern migrants that breed in Alaska and regularly migrate to South America (primary Charadriiformes) can have contact with birds from affected areas in Asia. The likelihood of the introduction of HPAI H5N1 through migratory birds was found to be very low as it is a probability conditioned to successful transmission in breeding areas and the probabilities of an infected bird migrating and shedding the virus as far as southern Brazil. The probability of wild species becoming exposed to H5N1-infected birds is high as they nest with northern migrants from Alaska, whereas for backyard poultry it is moderate to high depending on proximity to wetlands and the presence of species that could increase the likelihood of contact with wild birds such as domestic duck. The magnitude of the biological and economic consequences of successful transmission to poultry or wild birds would be low to severe depending on the probability of the occurrence of outbreak scenarios described. As a result, the risk estimate is greater than negligible, and HPAI H5N1 prevention strategy in the region should always be carefully considered by the veterinary services in Brazil.

Esophagectomy is associated with substantial morbidity and mortality, yet it is the only modality that offers the possibility of cure for esophageal and gastroesophageal junction (E-GEJ) adenocarcinoma. Several minimally invasive techniques have been developed to decrease the morbidity of the operation, but to date, the results have not led to its wide adoption in part due to their complexity. We developed a technique of laparoscopic-assisted transhiatal esophagectomy (LA-THE) with the idea of preserving some of the advantages of the minimally invasive approach while eliminating the degree of complexity and the time required to complete the operation solely using laparoscopy. The course of all patients who underwent LA-THE for E-GEJ adenocarcinoma at the University of Washington Medical Center was determined by analysis of all hospital records to determine perioperative variables, complications, and survival. Patients were also given a follow-up survey in order to assess long-term health-related quality of life (Gastrointestinal Quality of Life Index or GIQLI). Seventy-two patients underwent LA-THE between 1995 and 2007. Median age was 64 years (range, 42-83 years), and the median body mass index was 28 (range 17-35). Twenty-eight tumors (39%) were categorized as Siewert I, 41 (57%) as Siewert II, and 3 (4%) as Siewert III. Median operative time was 299min (range, 212-700min). All the resections were R-0. The median number of lymph nodes harvested was 11 (range, 2-32). Using the Dindo-Clavien classification of surgical complication, we had a total of 48 postoperative complications in 37 patients: 26 (53%) grade I, 20 (41%) grade II, 1 (2%) grade IIIb, 1 (2%) grade IVb, and 1 (2%) grade V complications. Median length of hospital stay was 9 days (range, 7-58 days). One patient (1.4%) died within 30 days. Overall, 3- and 5-year survival (calculated Kaplan-Meier) was 68% and 63%, respectively. Forty-nine patients (90% of those still alive) answered the GIQLI survey. Median follow-up was 26 months (range, 6-144 months). The mean GIQLI score was 108 (range, 74-138) from a maximum possible value of 144. Our study shows that LA-THE is feasible, safe, and effective in the treatment of adenocarcinoma of the esophagus and GEJ and should probably be considered an alternative to open esophagectomy and other minimally invasive techniques in the treatment of this disease.

Achalasia is a primary esophageal motor disorder that results in poor clearance of the esophagus. Although an esophagus filled with debris and undigested food should put these patients at risk for aspiration, the frequency with which the latter occurs has never been documented. In this study, we sought to determine the incidence of respiratory symptoms and complaints in patients with achalasia. A comprehensive symptom questionnaire was administered to 110 patients with achalasia presenting to the Swallowing Center at the University of Washington between 1994 and 2008 as part of their preoperative work-up. Questionnaires were analyzed for the frequency of respiratory complaints in addition to the more typical symptoms of dysphagia, regurgitation, and chest pain. Twenty-two achalasia patients with respiratory symptoms who had also undergone Heller myotomy and completed a post-op follow-up questionnaire were analyzed as a subset. Ninety-five patients (86%) complained of at least daily dysphagia. Fifty-one patients (40%) reported the occurrence of at least one respiratory symptom daily, including cough in 41 patients (37%), aspiration (the sensation of inhaling regurgitated esophagogastric material) in 34 patients (31%), hoarseness in 23 patients (21%), wheezing in 17 patients (15%), shortness of breath in 11 patients (10%), and sore throat in 13 patients (12%). Neither age nor gender differed between those with and those without respiratory symptoms. In the subset of patients with respiratory symptoms who had undergone Heller myotomy, respiratory symptoms improved in the majority after the procedure. Patients with achalasia experience respiratory symptoms with much greater frequency than the approximately 10% that was previously believed. Awareness of this association may be important in the workup and ultimate treatment of patients with this uncommon esophageal disorder.

The current state of research into the etiology of achalasia only allows for speculation. To date, several studies have been performed investigating genetic, immune, and infectious disease mechanisms; however, none of these have been conclusive. Further research into this topic is warranted given the severity of the disease, and it may be possible that all of these mechanisms are involved in the pathophysiology of the disease.

To analyse the epidemiological profile of 488 cases of leptospirosis in Rio de Janeiro, Brazil between 1997 and 2002, using a variety of methods of spatial epidemiology, to establish alert guidelines in general hospitals, which might be a tool to improve diagnosis and treatment of leptospirosis to reduce lethality rates.Scan statistics identified six space-time clusters, which comprised a range of 2 to 28 cases per cluster. Generalized linear mixed models were used to evaluate risk factors for a cluster case which incorporated individual characteristics and spatial information on environmental and climactic factors in a single model frame.Cluster case events were associated with heavy rainfall (OR 3.71; 95% CI 1.83-7.51). The model did not identify socioeconomic or environmental covariates that significantly influence the risk of developing a cluster rather than non-cluster case.Clustering of leptospirosis in this urban setting appears to be due to transmission during heavy rainfall.

Gallstone pancreatitis is caused by transient obstruction of the ampulla of Vater by a migrating gallstone. Intraglandular activation of pancreatic enzymes occurs (by an unclear mechanism), and their entry into the circulation causes most of the local and systemic events of pancreatitis. The diagnosis is based on history and physical examination, an elevation of serum amylase above 1000 IU/L, and ultrasound and CT scans. Endoscopic retrograde cholangiopancreatography can be used in less certain cases to confirm the presence of common bile duct stones. Because of the absence of an agent that can abort progression of the disease, therapy should consist of adequate resuscitation, nutritional support, and careful monitoring to detect early complications. In patients with mild pancreatitis, surgery usually can be performed within 48 or 72 hours of admission or as soon as symptoms and amylase levels return to normal. For patients with severe disease, endoscopic sphincterotomy is emerging as the therapeutic modality of choice. Elective treatment of the associated biliary disease should be performed during the same hospitalization after the acute phase of the disease has subsided.

Clinical information systems depend on close integration to workflow for success. We describe a method for user-driven design that guided our development of a computerized rounding and sign-out system. The resulting system supported clinical workflow sufficiently well that it spontaneously attracted new users, required no training, and is currently used by 95% of the house staff at two academic medical centers.

Background: A correlation between elevation of pro-inflammatory cytokines and white matter injury or abnormal neurologic outcome has been established in the preterm infant. In the full-term neonate, few studies exist linking elevation of cytokines with encephalopathy and poor neurodevelopmental outcome. Our aims were to investigate if serum interleukin-6 concentrations in delivering mothers and their offspring at birth are associated with perinatal asphyxia, and to examine the relation of interleukin-6 levels to the severity of hypoxic-ischemic encephalopathy and to the neurological outcome. Design and methods: Serum interleukin-6 levels were measured at birth, 24 and 48 h of life in 50 consecutive term uninfected newborns with perinatal asphyxia and 113 randomly selected healthy term newborns, and at delivery in their mothers. Results: The median cord interleukin-6 concentrations in the infants who developed hypoxic-ischemic encephalopathy was 376-fold as high as the values in the normal infants (P < 0.0001) and 5.5-fold as high as those in the infants with asphyxia who did not develop hypoxic-ischemic encephalopathy (P < 0.05). There was also a significant relationship between interleukin-6 and the degree of hypoxic-ischemic encephalopathy, and between interleukin-6 and neurodevelopmental outcome at 2 years of age. Regardless of outcome, in the asphyxiated infants the interleukin-6 values were significantly lower at both 24 and 48 h of life than at birth, with a significant decline from 24 to 48 h of life. Among mothers of the asphyxiated neonates, there were no significant differences in interleukin-6 concentrations between those delivering neonates with and without hypoxic-ischemic encephalopathy. Conclusions: Measurement of IL-6 concentrations in the umbilical cord of neonates with perinatal asphyxia may be useful to identify early, and in a relatively simple way, those who are most likely to have subsequent brain injury and adverse outcome.

Esophageal Heller myotomy and a partial antireflux procedure for achalasia are the ideal procedures to benefit from the advances in minimally invasive surgery. The magnified view of the operative field provided by the laparoscope allows precise division of the esophageal muscle fibers with excellent results. Laparoscopic Heller myotomy results in reduced postoperative pain, less morbidity, shorter hospitalization, better resolution of dysphagia, and less postoperative heartburn when compared with the open abdominal and even the thoracoscopic approach. A longer myotomy especially at the distal end, and a loose, well-formed partial fundoplication are the keys to a successful outcome. Superior long-term results after surgical myotomy when compared with nonsurgical interventions argue strongly in favor of surgery in any patient who is fit enough to undergo general anesthesia.

During the last decade, minimally invasive surgery has replaced open surgery in the treatment of esophageal achalasia. This new approach, in fact, determines results similar to the open approach, but is associated to a shorter hospital stay, minimal postoperative discomfort, and faster return to regular activity. Between 1991 and 1998, 168 patients underwent a cardiomyotomy by minimally invasive techniques. Good or excellent results were obtained in 85% of patients after thoracoscopic myotomy, and 93% of patients after laparoscopic myotomy and partial fundoplication. The latter procedure was followed by a lower incidence of postoperative gastroesophageal reflux (60% versus 17%). Laparoscopic Heller myotomy and partial fundoplication has emerged as the procedure of choice for esophageal achalasia, and it should be considered today the primary form of treatment for this disease.

During the course of a laparoscopic Heller myotomy, a patient thought to have primary achalasia was found instead to have an adenocarcinoma of the gastroesophageal junction. Aspects of this patient's clinical course, which are exemplary of malignant pseudoachalasia, are discussed, as are ways in which this not uncommon error in diagnosis can be avoided.

The aim of this prospective study was to determine the prevalence and characteristics of acid gastro-oesophageal reflux (GER) in patients with idiopathic pulmonary fibrosis (IPF). Sixty-five consecutive patients with well-defined IPF were subjected to 24-h pH monitoring and oesophageal manometry. A total of 133 consecutive patients with intractable asthma and symptoms of GER were used as comparisons. The prevalence of abnormal acid GER in IPF patients was 87%, with 76% and 63% demonstrating abnormal distal and proximal oesophageal acid exposures, respectively. Abnormal acid GER was significantly more common in IPF patients than asthma patients. Only 47% of IPF patients experienced classic GER symptoms. Despite treatment with standard doses of proton pump inhibitors (PPIs), 12 out of 19 patients receiving PPIs during the 24-h pH monitoring had abnormal oesophageal acid exposures by pH probe. There was no correlation between IPF severity and acid GER severity. In conclusion, abnormal acid gastro-oesophageal reflux is highly prevalent, but often clinically occult in patients with idiopathic pulmonary fibrosis. Standard doses of proton pump inhibitors may not suppress the acid gastro-oesophageal reflux in this population. Therefore, further studies are needed to determine if acid abnormal gastro-oesophageal reflux represents an important risk factor for idiopathic pulmonary fibrosis development or progression, and if optimal suppression of acid gastro-oesophageal reflux slows the progression of idiopathic pulmonary fibrosis and/or decreases episodic exacerbations of idiopathic pulmonary fibrosis.

This study was done to determine the effects of duration of obstruction on severity of lesions in patients with acute pancreatitis of biliary origin.This case controlled study used patient data collected prospectively on protocol during a 27-year period in a university teaching hospital. We studied a group of 97 patients with acute pancreatitis, all with an impacted stone at the ampulla of Vater at exploration (Group Ob), and a control group of 49 patients with acute gallstone pancreatitis who experienced spontaneous ampullary disobstruction within 24 hours from the onset of symptoms and who showed a patent ampulla at exploration (Group Cont). Duration of obstruction was defined as the time elapsed between the onset of symptoms and exploration in Group Ob, and from the onset of symptoms until the appearance of signs of ampullary disobstruction in Group Cont. Severity of disease in both groups was determined by the appearance of the pancreas at exploration. Patients in Group Ob were divided into three subgroups according to duration of obstruction: under 24 hours, 25 to 48 hours, and more than 48 hours.The incidence of severe pancreatic lesions was higher in Group Ob than in Group Cont (19.7 percent compared to 6.1 percent, p.01). Mean duration of obstruction was also significantly longer in Group Ob than in Group Cont (42.4 hours compared to 10.6 hours). In the subgroups of patients whose obstruction lasted under 48 hours, the incidence of severe lesions was low: in the 24 hours or fewer group, severe lesions were observed in 8.1 percent (3 of 37); and in the 25 to 48 hours group, the incidence was 10.6 percent (5 of 47). Neither subgroup differed significantly from Group Cont (6.1 percent, 3 of 49). When duration of obstruction exceeded 48 hours, however, frequency of severe lesions increased significantly to 84.6 percent (11 of 13) (p.001).The findings in this study suggest that duration of ampullary obstruction is a major factor determining the severity of pancreatic lesions: severe pancreatic lesions are rare in patients whose obstruction lasts not more than 48 hours. In contrast, pancreatic necrosis develops in nearly all patients with obstruction beyond 48 hours. It may be safe to treat patients conservatively during the first day of the illness. If obstruction is not resolved by the second day, endoscopic retrograde cholangiopancreatography or surgical intervention must be carried out.

Achalasia, nutcracker oesophagus and diffuse oesophageal spasm are primary oesophageal motility disorders whose treatment has been substantially impacted by the advent and development of minimally invasive surgery. Although several studies had shown that oesophageal myotomy was effective in the treatment of several of these disorders, particularly in the more advanced stages, many of the patients who could have benefited from an operation were instead with medications or balloon dilation, sometimes despite repeated failures of this form of therapy. To a certain extent, this reflected patient and physicians' concerns with the post-operative discomfort and the long recovery time inevitably associated with the performance of a thoracotomy or laparotomy. Today, however, we and others have shown that minimally invasive techniques allow an operation to be performed with the same excellent results provided by open surgery, but with a shorter hospital stay, minimal post-operative discomfort, and faster return to work. We performed our first thoracoscopic myotomy for achalasia in January of 1991, initially using a technique developed by Dr. Cuschieri, which we modified as we gained experience. Subsequently, we extended the same technique to the treatment of diffuse oesophageal spasm and nutcracker oesophagus. This report describes our experience at the University of California at San Francisco and the University of Washington in Seattle for the diagnostic and therapeutic approach to patients with primary oesophageal motility disorders.

In summary, the authors believe that minimally invasive surgery has added a new dimension to the treatment of achalasia. Thoracoscopic myotomy is feasible, safe, and effective in relieving dysphagia in the great majority of individuals affected with this disease without the many problems associated with dilatation; thus, the authors offer it to patients with achalasia as the initial and preferred form of treatment. Whether an antireflux procedure should be routinely added and whether a laparoscopic rather than a thoracoscopic approach is preferred, remains unanswered questions at this time.

Achalasia of the esophagus is a disease characterized by the lack of peristalsis, the lack of adequate and complete lower esophageal sphincter relaxation, and the presence of high pressure at the lower end of the esophagus. Therapy is directed to decreasing resistance to flow through the sphincter. To a certain degree both pneumatic dilatation and Heller myotomy achieve this effect in the majority of patients, facilitating esophageal emptying. Surgical treatment, however, has an advantage over dilatation: A myotomy performed under direct vision can relieve the obstruction more precisely, more often, and with fewer complications than the blind rupture of the muscle fibers obtained with dilatation.

The treatment of esophageal achalasia has been controversial for many years. Even if a myotomy performed through a left thoracotomy gives better results than pneumatic dilatation, the fear of an operation with the associated postoperative pain and disability has kept patients away from this form of treatment. Minimally invasive surgery allows the same results obtained with open surgery, with a short hospital stay, minimal postoperative discomfort, and a fast recovery time. A thoracoscopic or laparoscopic Heller's myotomy should be considered today the primary form of treatment for esophageal achalasia.

Modern advances in equipment and techniques have made it possible to treat many esophageal diseases with minimally invasive techniques. This chapter describes the impact of thoracoscopy and laparoscopy on esophageal surgery, with particular emphasis on the technique and results of esophageal myotomy, antireflux operations, and esophageal resection.

In the past 2 years, a revolution of unprecedented scope has occurred in biliary surgery. Laparoscopic cholecystectomy, first performed in 1987, has now become the procedure of choice to treat cholelithiasis. Because laparoscopic surgery proliferated in the absence of controlled clinical trials, concerns have been raised regarding its complications. This article reviews the technique of laparoscopic cholecystectomy, examines its feasibility and complications, and discusses the evolving role of intraoperative cholangiography and the approach to common bile duct stones. In a separate section, we review the year's literature on gallstone pancreatitis and on surgical treatment of benign biliary strictures.

Hypothesis: We hypothesized that hand-assisted laparoscopic surgery (a new technique that involves a surgeon's hand passing through a pneumoperitoneum-protecting sleeve device and assisting in laparoscopic surgery) is feasable and outcomes are comparable to purely laparoscopic procedures in selected cases.

We studied the course of 100 consecutive patients who underwent surgery for pain or biliary obstruction from chronic pancreatitis or both between 1958 and 1982. Patients with pancreatic pseudocysts were excluded. Ten patients had pancreatic resection after previous pancreatic surgery had failed to control pain. Ten of 47 patients (21 percent) studied between 1972 and 1981 had bile duct entrapment from chronic pancreatitis and required biliary bypass operations. The results of longitudinal pancreaticojejunostomy were good in 67 percent of the patients, fair in 18 percent of the patients, and poor in 15 percent of the patients. The results of partial pancreatectomy were good in 60 percent of the patients (all with disease limited to the tail), fair in 20 percent of the patients, and poor in 20 percent of the patients. The results of subtotal pancreatectomy were good in 31 percent of the patients, fair in 37 percent of the patients, and poor in 32 percent of the patients. The results of pancreatic resection in patients with previous unsuccessful surgery for pain relief were good in only 10 percent of the patients. Biliary obstruction is present in many patients with chronic pancreatitis and must be treated surgically to prevent the development of biliary cirrhosis. Hemipancreatectomy is useful in patients with disease limited to the tail. The results of subtotal pancreatectomy are discouraging, especially in patients with a previous unsuccessful operation for pain. When the pancreatic duct is dilated, however, longitudinal pancreaticojejunostomy gives long-lasting relief of pain in most patients.

The technique of 24 hour esophageal pH monitoring (24 hour pH test) is described. Experience with the 24 hour pH test in 393 patients with suspected esophageal disease has shown the clinical usefulness of the test in objectively determining the presence of gastroesophageal reflux. The test was effective in evaluating atypical symptoms of gastroesophageal reflux such as respiratory symptoms and chest pain and, in children, failure to thrive and recurrent pneumonia. The 24 hour pH test was particularly useful in evaluating patients who were referred with other abdominal or thoracic disease and had, in addition, symptoms suggestive of gastroesophageal reflux on history. The test helped to unsnarl the cause of recurrent symptoms after an esophageal myotomy for achalasia or an antireflux procedure. Of 179 patients with typical symptoms of gastroesophageal reflux, 27% had normal 24 hour test results and were subsequently diagnosed as having another cause for their symptoms. Of 146 patients who had normal findings on esophagoscopy, 54% were shown to have abnormal gastroesophageal reflux on 24 hour pH monitoring, indicating lack of sensitivity of endoscopy to detect reflux. In addition, the 24 hour pH test identified patterns of abnormal reflux and indicated those patients most at risk for development of stricture. The test is well tolerated by the patients, simple to use, and dependable when performed and read as described. The clinical use of the 24 hour pH test brings objectivity to the evaluation of exophageal disease that has hitherto not been available.

We studied gallbladder bile flow before, during, and after cholesterol gallstone formation in the prairie dog using infusion cholescintigraphy with 99mTc-diethyl iminodiacetic acid. In 18 fasting animals partitioning of bile between gallbladder and intestine was determined every 15 min for 140 min, and gallbladder response to cholecystokinin (5 U/kg X h) was calculated from the gallbladder ejection fraction. Ten prairie dogs were then placed on a 0.4% cholesterol diet and 8 on a regular diet, and the studies were repeated 1, 2, and 6 wk later. The proportion of hepatic bile that entered the gallbladder relative to the intestine varied from one 15-min period to the next, and averaged 28.2% +/- 5.1% at 140 min. Partial spontaneous gallbladder emptying (ejection fraction 11.5% +/- 5.6%) was intermittently observed. Neither the number nor the ejection fraction of spontaneous gallbladder contractions changed during gallstone formation. By contrast, the percent of gallbladder emptying in response to cholecystokinin decreased from 72.1% +/- 5% to 25.9% +/- 9.3% (p less than 0.025) in the first week and was 14.3% +/- 5.5% at 6 wk (p less than 0.01 from prediet values, not significant from first week). Gallbladder filling decreased from 28.2% +/- 5.1% to 6.7% +/- 3% (p less than 0.01), but this change was only observed after 6 wk, when gallstones had formed. This study shows that bile flow into the gallbladder during fasting is not constant; the gallbladder contracts intermittently; gallbladder emptying in response to exogenous cholecystokinin is altered very early during gallstone formation; and gallbladder filling remains unaffected until later stages, when gallstones have formed.

The incidence of aspiration, the causative esophageal pathophysiology, and the results of surgical therapy were evaluated in 100 patients with abnormal gastroesophageal reflux documented by 24-hour esophageal pH monitoring. Based on historical evidence, 48 patients were suspected to be aspirators. Eight patients had documented episodes of aspiration (drop on esophagela pH, followed by acid taste in mouth and onset of cough or wheezing spell) during the monitoring period. Nine patients were considered to be potential aspirators because they presented oral acid regurgitation without development of pulmonary symptoms. In five patients a primary respiratory disorder (PRD) induced gastroesophageal reflux. The remaining 78 patients had abnormal reflux without aspiartion or regurgitation. Aspirators had a 75% incidence of esophageal motor abnormality on manometry, and the clearance of refluxed acid was significantly delayed in the supine position. A history of heartburn and endoscopic evidence of esophagitis were present in only half of the patients who were documented aspirators. Potential aspirators were spared from aspiration by rapid esophageal clearance of refluxed acid unaffected by changes in body position. Patients with a PRD had higher distal esophageal segment (DES) pressure and normal esophageal motility with minimal esophagitis. Nonaspirators significantly improved their clearance while in the supine position, emphasizing the protective effect of esophageal peristalsis against aspiration. An antireflux procedure in five aspirators raised the DES pressure significantly and returned the reflux status to normal by 24-hour pH-monitoring standards. The incidence of aspiration appears to be less than that suspected by history and is due to a motor disorder that interferes with the ability of the esophagus to clear reflex acid. Abnormal pulmonary symptoms can induce or result from gastroesophageal reflux and, when the latter occurs, an antireflex procedure stops both reflux and aspiration.

We studied the effects of vagotomy on gallbladder (GB) motility in prairie dogs and humans with infusion cholescintigraphy. Twelve male prairie dogs were anesthetized and given an intravenous infusion of 120 microCi of diethyl-HIDA for 150 minutes. Images were acquired every 10 minutes. Then cholecystokinin (CCK)-8, 1.5 micrograms/kg, was given as a bolus, and images were acquired for another 30 minutes. We repeated the studies giving 300 micrograms/kg of atropine 20 minutes before administration of CCK-8. All animals underwent truncal vagotomy, and the studies were repeated 1 and 3 months later. The GB filled in a stepwise fashion; partitioning of bile varied from one 10-minute period to the next and averaged 20% +/- 2%/80% +/- 3% during the 150-minute period. Episodic partial GB emptying (ejection fraction 19% +/- 2%; intervals of 70 +/- 5 minutes) occurred during this phase. GB filling and partitioning of bile were unchanged after vagotomy. GB ejection fraction in response to CCK-8 was 69% +/- 6% in controls, 74% +/- 5% after atropine, 78% +/- 8% 4 weeks after vagotomy, and 66% +/- 6% 3 months after vagotomy. Sixteen human subjects were studied after parietal cell vagotomy (six patients) or truncal vagotomy and drainage (10 patients). GB filling average 2.5% +/- 2% per minute in patients who underwent truncal vagotomy and 3% +/- 1% per minute in patients who underwent parietal cell vagotomy. GB emptying in response to CCK-33 (0.02 U/kg/min) was 74% +/- 7% in patients who underwent truncal vagotomy and 82% +/- 4% in patients who underwent parietal cell vagotomy. Thus neither GB filling nor GB emptying in response to CCK was altered by cholinergic blockade or vagotomy.

We studied 53 patients with severe gastrointestinal symptoms thought to be due to a gastric motility disorder. Sixty-six percent had had a previous operation on the stomach, and 21 percent had insulin-dependent diabetes mellitus. Based on clinical, radiographic, and endoscopic findings, 48 patients were thought to have gastroparesis, 3 were thought to have dumping, and 2 had no diagnosis. Measurement of gastric emptying of solids showed that gastric emptying was normal in 12 patients, rapid in 15 patients, and slow in 26 patients. Further evaluation showed that half of the patients with normal gastric emptying, and one third of those with rapid gastric emptying had other diseases of the gastrointestinal tract that responded well to surgery. Of those patients with dumping, diet modification was effective in 40 percent, and half of those who did not respond to dietary manipulations did well after reoperation. Nineteen patients with delayed gastric emptying were treated with metoclopramide. Sixty percent of those without previous gastric surgery responded, whereas only 25 percent of those with previous gastric surgery had good results. The rate of gastric emptying improved following reoperation in 9 (90 percent) of 10 patients with delayed gastric emptying (4 who had not responded to metoclopramide). Gastric emptying was measured again in 15 patients after treatment. The changes after treatment paralleled the clinical response. These studies indicate that gastroparesis cannot be reliably diagnosed on the basis of clinical findings and standard tests. Gastric emptying studies are essential to diagnose and treat patients thought to have gastric motility disorders, and to evaluate the results of therapy.