Biliary, Pancreatic, and Sphincter of Oddi Electrical and Mechanical Signals Recorded During ERCP

Measurements of biliary tract motility havefocused on radiologic and pressure measurements toquantify biliary motility rather than measurements ofelectrical activity of the biliary tract. We previously reported the recording of biliary electricalsignals during ERCP and now report on the continueddevelopment and validation of a system to measurebiliary tract electrical activity as well as biliarymechanical activity. In 26 patients presenting with avariety of clinical indications, we recordedmeasurements of electrical activity from the common bileduct sphincter (16 patients), pancreatic duct sphincter(eight patients), and/or sphincter of Oddi (eightpatients). Electrical recordings were performed with aspecially modified ERCP catheter, using two circularelectrodes as well as a custom catheter that measured both electrical and mechanical activity.Electrical activity of the biliary tract wassuccessfully recorded in 25 of 26 patients (96%),including the common bile duct sphincter (16 patients,62%), pancreatic duct sphincter (eight patients, 31%) andsphincter of Oddi (eight patients, 31%). Along with theelectrical recordings, common bile duct sphinctermechanical activity was recorded in 12 patients (67%), pancreatic duct sphincter mechanical activityin six patients (33%), and sphincter of Oddi mechanicalactivity in six patients (33%). Frequency analysis ofelectrical signals revealed a mean frequency(cycles/min) of 4.7 ± 0.5 in the common bile ductsphincter, 4.1 ± 0.6 in the pancreatic ductsphincter, and 4.9 ± 0.7 in the sphincter ofOddi. Phasic mechanical frequency in cycles per minutewas recorded at a frequency of 4.8 ± 0.5 in common bileduct sphincter, 4.0 ± 0.6 in pancreatic ductsphincter, and 5.3 ± 0.9 in sphincter of Oddi.Tonic pressure (averaged 12.1 ± 1.5 mm Hg) incommon bile duct sphincter, 12.4 ± 1.4 mm Hg inpancreatic duct sphincter, and 15.0 ± 5.1 mm Hgin sphincter of Oddi. Analysis of wave form propagations(noted as percentage antegrade, retrograde, orindeterminant) revealed 50% antegrade, 23% retrograde, and 27%indeterminant). One patient was recorded on twooccasions via ERCP; the same patient had anintraoperative recording. All three recordings showedsimilarities. We conclude that measurements of biliary,pancreatic, and sphincter of Oddi electrical andmechanical activity are feasible and can be done as partof ERCP. There was good correlation between biliarytract electrical and mechanical events and differentwave form characteristics were noted for different partsof the biliary tree. Further studies are warranted toevaluate the potential usefulness of measurement of biliary tract electrical activity, and toconfirm its correlation with mechanical events in thepancreato-biliary tree.     

Predictors of outcome in hospitalized patients with severe hyponatremia

Severe hyponatremia is associated with increased morbidity and mortality. Clinicians treating patients with severe hyponatremia are often torn between a desire to promptly raise serum sodium concentration to a "safe range," and at the same time, to avoid excessively rapid correction of hyponatremia. The aim of this study was to assess the prevalence of severe hyponatremia in hospitalized patients, the etiologic factors involved, as well as treatment and outcome of the patients using a retrospective case series. METHODS: Retrospective study of 168 patients with severe hyponatremia (< 115mmol/L) seen at Grady Memorial Hospital, a tertiary teaching hospital, in Atlanta, Georgia, from 1997-2001. The main outcome measures of interest were death during admission or occurrence of neurologic symptoms before, during or after therapy. RESULTS: One hundred sixty-eight patients met the inclusion criteria out of a total of 5994 patients with hyponatremia treated at our hospital over the study period. Eighty-nine patients (52.9%) were symptomatic. The mean absolute serum sodium at 48-hours of therapy was 120.02 +/- 8.31 mmol/L. Respiratory failure and/or hypoxia was present in 28 patients (16.7%); sepsis was documented in 16 patients (9.5%). Mortality rate was high, 34 patients died (20.2%). On multivariate analysis factors with strong association with mortality of patients with severe hyponatremia were hypoxia, presence of neurologic symptoms, slow correction rates and a diagnosis of sepsis. CONCLUSIONS: The mortality associated with severe hyponatremia remains high. Sepsis, respiratory failure and the presence of symptoms predict poor outcome in hospitalized patients with severe hyponatremia. More aggressive therapy with 3% saline may improve outcome in symptomatic patients. Our data suggest that a slow rate of correction in severe hyponatremia is associated with higher mortality than rapid correction, at least in the short-term.     

Comprehensive Musculoskeletal Sonographic Evaluation of the Hand and Wrist

Sonography is widely used for evaluation of hand and wrist lesions. The easy accessibility, cost‐effectiveness, and good diagnostic accuracy of sonography coupled with the numerous benefits of real‐time imaging make it desirable. The aim of this article is to describe the typical sonographic appearances of lesions in the hand and wrist that are encountered frequently in routine clinical practice, such as inflammatory arthropathies, tumors, traumatic injuries, foreign bodies, and nerve entrapment syndromes. Relevant anatomy, scanning methods, and recent developments in musculoskeletal sonography are also discussed.