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Biomedical subjects

M Keuchel

Publications and source records attributed to M Keuchel.

16 recordsLinked to original sources
PubMed2005

Small bowel endoscopy.

Video capsule endoscopy continues to be the major focus in papers dealing with diagnostic small-bowel endoscopy. Although capsule endoscopy is used for a variety of indications, its major field of application is still obscure bleeding from the small intestine, where it can be regarded as a first-line test. There is increasing evidence that capsule endoscopy for suspected Crohn's disease may be diagnostic in individual cases after inconclusive conventional tests. Push enteroscopy is the clinical reality for biopsy and treatment in the proximal small bowel, whereas intraoperative enteroscopy is used for distal or diffuse small-intestinal disorders. Further reports on double-balloon enteroscopy suggest that this method may be able to replace at least intraoperative enteroscopy in many circumstances. The availability of specific antibody tests for celiac disease is leading to recurrent interest in endoscopy and histology, showing that villous atrophy and lymphocytic infiltrates are typical, but not specific, findings.

Capsules↗
PubMed2005

Structured terminology for capsule endoscopy: results of retrospective testing and validation in 766 small-bowel investigations.

BACKGROUND AND STUDY AIMS: Capsule endoscopy (CE) is an effective means of investigating the small bowel in patients with gastrointestinal diseases. Computerized reports are frequently used in endoscopy, and the Minimal Standard Terminology (MST) has been promoted by endoscopy societies as the official vocabulary for endoscopy. The aims of this study were to design a lexicon for CE reports based on the principles of the MST and to validate lists of terms for describing findings and reasons for performing a CE by cross-matching them with the results of CE procedures collected during ongoing clinical studies. MATERIALS AND METHODS: A consensus-based Capsule Endoscopy Structured Terminology (CEST) was developed by experts involved in CE studies. Lists of terms suitable for CE were designed for the various sections of an endoscopic report. They were then correlated with the corresponding MST lists for duodenal and intestinal endoscopy. The results of 766 CE procedures, collected in an electronic case record form (eCRF), were analyzed to provide lists of reasons for performing the procedures and of the findings. The eCRF provided only a limited number of items for each data field, along with free-text facilities. Only descriptions pertaining to the small bowel were analyzed. Lists of terms were then reviewed by two experts to group obvious synonyms. The accuracy of the CEST was defined beforehand as the capability to describe 90 % of entries. RESULTS: A total of 766 CE procedures were analyzed. The eCRF included 824 entries as reasons for the examination in 655 CEs (1.3 per procedure). These represented 122 different expressions. After grouping of synonyms, 28 expressions remained. Among them, 10 were matched with terms from the list of reasons for performing CE offered in the CEST. These were the most frequently used, accounting for 768 entries in this field (93.2 %). All eCRFs contained at least one description of findings. A total of 109 CE procedures were classified as normal (14.3 %). A total of 2624 entries for abnormal findings were recorded for 657 procedures (4.0 per procedure). In all, 213 different expressions were used to describe abnormal findings. After grouping of synonyms, 52 expressions remained. Among these, 27 were matched with terms from the list of findings in the CEST, covering 2403 entries (91.6 %). CONCLUSIONS: In this study, CEST terms were capable of describing more than 90 % of the reasons for performance and of the findings in an unselected set of CE procedures. CEST is therefore suitable for use as the standard lexicon for CE reports. Adopted as a standard, it could significantly improve the quality of the data collected and reported in CE studies.

Endoscopy, Gastrointestinal↗
PubMed2000

[Acute pancreatitis. Early elective endoscopic intervention].

Early endoscopic intervention is required in the treatment of biliary pancreatitis in the presence of cholangitis or jaundice, possibly with dilated common bile duct. Also patients with predicted severe disease, lack of spontaneous clinical improvement or progressive jaundice might benefit from endoscopic retrograde cholangiopancreatography (ERCP) with sphincterotomy. If endoscopy is indicated, it should be performed as soon as possible. Injection of contrast medium into a dilated bile duct is accompanied by the risk of cholangitis. Therefore therapeutic decompression by sphincterotomy and stone extraction is necessary, or, if this is not possible, insertion of a naso-biliary tube for drainage. Prophylactic use of antibiotics is recommended periinterventionally. Early endoscopic intervention is not necessary in patients with mild biliary pancreatitis and spontaneous clinical improvement. Here, ERCP can be performed later, if indicated.

Acute Disease↗
PubMed2000

Plasmapheresis in life-threatening verapamil intoxication.

Verapamil intoxications are life-threatening conditions with a far too often fatal outcome. In 2 patients, severe suicidal intoxication by 2.4 g and 9.6 g of verapamil orally resulted in life threatening hypotension and bradycardia with the need of heart-pacing and resuscitation. Plasmapheresis was started within less then 4 hours after intoxication and seemed to reduce the verapamil plasma concentration to less then 40%. A dramatic improvement of cardiovascular stability was already observed during plasmapheresis. In-vitro plasmapheresis was performed to verify the effectiveness of the extracorporeal detoxification. Verapamil was removed out of the blood by a clearance of 29.2 ml/min at blood flow of 200 ml/min. In conclusion, severe verapamil poisoning should be treated by early aggressive gut decontamination and an appropriate management of the haemodynamic complications. In case of lack of effectiveness for stabilisation, plasmapheresis can reduce verapamil related life threatening symptoms and bridge the time for the hepatic detoxification.

Acute Disease↗
PubMed1997

Impact of profile haemodialysis on intra-/extracellular fluid shifts and the release of vasoactive hormones in elderly patients on regular dialysis treatment.

In 15 patients with end-stage renal failure and proven coronary heart disease, profile haemodialysis with decreasing ultrafiltration rate and hyperionic, decreasing dialysate solute concentration was compared with conventional, extracorporeal bicarbonate haemodialysis (Na+D = 138 mmol/l). Body fluid distribution and the release of vasoactive hormones (plasma renin activity, aldosterone, norepinephrine, epinephrine, and atrial natriuretic peptide) were investigated. Haemodialysis with constant ultrafiltration rate and constant dialysate composition (A) was followed by two dialysis profiles: decreasing ultrafiltration rate (B) and additional hyperionic, decreasing dialysate sodium concentration (C). In all 15 patients, the dialysis procedures (A) - (C) were used for 2 weeks each with six sessions, the last being taken for investigation. Body fluid distribution was calculated. In patients with serum sodium above 136 mmol/l, the conventional dialysis (A) as well as the Uf profile (B) showed a net fluid shift from extracellular volume (ECV) to intracellular volume (ICV). Using the profile with hyperionic, decreasing Na+D (C), the reverse fluid shift with decreasing ICV was achieved not only in those with serum Na+ <136 mmol/l, but also in those with serum Na+ > or = 136 mmol/l. The release of vasoactive hormones decreased already at profile haemodialysis (B) compared with (A) and was further reduced in (C). These results would suggest, profile dialyses B and C to have less impact on the cardiovascular system in elderly patients assuming higher patient comfort compared with the standard dialysis procedure. A higher benefit was obtained in C compared with B, presumably due to the additional prevention of the ICV shift and plasma volume depletion in patients with initial serum sodium > or = 136 mmol/l using transiently hyperionic Na+D. These results show that in elderly patients, hyperionic profile haemodialysis (Na+D > Na+S) had less impact on cardiovascular regulation than conventional bicarbonate dialysis.

Aged↗
PubMed1991

Fluid-shift during computer-modulated profile hemodialysis (CMP-HD).

Computer-modulated profile hemodialysis was examined for patients' comfort and fluid-shift. Fifteen patients were studied after two weeks of dialysis with each of the following profiles: A): constant ultrafiltration (UF) and dialysate sodium (138 mmol/l); B): decreasing UF; C): decreasing UF and decreasing high dialysate sodium (starting 10% above serum-sodium, with a gradual reduction to 138 mmol/l in the fourth hour). Patients with a calculated increase of intracellular volume (ICV) during dialysis had more complaints after dialysis than the others. ICV decreased in all patients with low serum-sodium (less than 136 mmol/l) during all profiles, whereas in patients with higher sodium, only profile C led to a decrease of ICV. However, interdialytic weight gain increased about 75% in patients with low serum-sodium under profile C. The sodium profile could help in preventing imbalance without side effects in patients with high sodium.

Aged↗
PubMed1991

[Differential diagnosis of transplant function disorders in therapy with monoclonal antibodies OKT3].

The use of OKT3 monoclonal antibodies has improved the immunosuppressive therapy. Due to the high efficiency of this treatment there is an increased risk of overimmunosuppression and occurrence of life-threatening viral infections. Therefore a cautious application of OKT3 is mandatory, a reliable differential diagnosis of the deteriorating graft function essential. In this study the high diagnostic value of urinary neopterin in the early and reliable diagnosis of CMV infection under OKT3 therapy in contrast to serum amyloid A as a marker of rejection could be shown. A differential therapy, supporting or reducing the immunosuppression, might be facilitated by daily monitoring of the neopterin and serum amyloid A.

Adult↗
PubMed1990

Influence of computer-modulated profile haemodialysis on cardiac arrhythmias.

To reduce hamodialysis-induced ventricular arrhythmias, each of 15 patients (age 66.9 +/- 6.2 years) with end-stage renal disease and cardiac irregularities was treated subsequently with four different computer-modulated bicarbonate haemodialysis profiles (A-D) for 2 weeks respectively: (A) constant UF, dialysate Na (138 mmol/l) and K (2 mmol/l); (B) decreasing UF, otherwise as (A); (C) decreasing UF and Na (starting with 10% higher than serum Na), otherwise as (A); (D) decreasing UF and Na, adapted K to achieve a maximal reduction of serum K of only 15%/h. Cardiac monitoring was done by 11 h ECG. Only in haemodialysis profile D a distinct reduction of ventricular extrasystoles during and after haemodialysis was obtained. It was accompanied by an improvement in the Lown classification. In addition, a weak but highly predictive correlation between the number of ventricular extrasystoles in the last hour of dialysis and the difference between pre- and post-dialysis potassium concentration in the serum could be established (r = 0.37; P less than 0.004). Computer-modulated potassium profile haemodialysis is a useful tool to reduce the number and severity of ventricular extrasystoles.

Aged↗
PubMed1985

Human early pregnancy factor: application of the monoclonal antibody anti-HuLyt 3 in the rosette inhibition test and in a cellular radioimmunoassay.

Using the monoclonal antibody anti-HuLyt 3, raised rosette inhibition titres were observed when lymphocytes were preincubated with early human pregnancy sera, although this was not a consistent finding. Results obtained from a cellular radioimmunoassay suggest that this enhancement of rosette inhibition is not due to interference with antibody binding.

Antibodies, Monoclonal↗