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D Külling

Publications and source records attributed to D Külling.

13 recordsLinked to original sources
PubMed2001

Is histological investigation of polyps always necessary?

BACKGROUND AND STUDY AIMS: To assess whether polyp histological type can be predicted by patient characteristics and endoscopic polyp findings. PATIENTS AND METHODS: 1681 polyps in 494 patients were categorized as advanced adenomas (villous component or severe dysplasia or early cancer) or insignificant polyps. Chi-squared tests were used to analyze whether polyp histological type could be predicted based on patient age (< 60 vs. > or = 60 years), gender, family history of colon polyps or cancer, presence of anemia, polyp size (< or = 5 mm vs. > 10 mm), and location (left- vs. right-sided). RESULTS: Insignificant polyp histology (n = 1337) correlated with patient age < 60 years (P = 0.0026), lack of anemia (P< 0.0001), polyp size < or = 5 mm (P < 0.0001), and right-sided location (P= 0.0058). Stepwise inclusion of these parameters demonstrated that the association of a < or = 5 mm right-sided polyp in a patient < 60 years yielded the highest combined predictive value (96.2%) for an insignificant polyp. Conversely, age > or = 60 years, presence of anemia, polyp size > 10 mm, or left-sided location, as single or combined parameters, demonstrated a maximum predictive value of only 75.4% for an advanced adenoma. CONCLUSIONS: A small right-sided polyp in a young patient is associated with a small risk (3.8 %) for advanced adenomatous tissue, indicating that histological investigation of such a polyp might not always be necessary. However, the recent recognition of flat adenomas and "mini" de novo colon carcinomas in the European population also may limit the usefulness of small polyp diameters in the exclusion of severe polyp histology.

Adenoma↗
PubMed2001

Safer colonoscopy with patient-controlled analgesia and sedation with propofol and alfentanil.

BACKGROUND: The aim of this study was to assess the efficacy of patient-controlled analgesia and sedation with propofol/alfentanil for colonoscopy compared with continuous drug infusion and conventional nurse-administered medication. METHODS: One hundred fifty patients undergoing colonoscopy on an outpatient basis were randomly assigned to 1 of 3 medication regimens. To maintain blinding, all patients were connected to an infusion pump. Group I patients could self-administer boluses of 4.8 mg propofol and 125 microg alfentanil without restriction. Group II patients received a continuous infusion with 0.048 mg/kg propofol and 0.12 microg/kg alfentanil per minute. Group III patients received intravenous premedication with 0.035 mg/kg midazolam and 0.35 mg/kg meperidine. RESULTS: There were no differences between the groups with respect to pain (visual analogue scale) and procedure time. Patient-controlled analgesia and sedation with propofol/alfentanil (group I) resulted in less of an increase in the transcutaneous partial pressure of carbon dioxide (p = 0.0004) during colonoscopy and less of a decrease in mean arterial blood pressure (p = 0.0021) during recovery, as well as more complete recovery (p = 0.0019) after 45 minutes compared with conventional administration of midazolam/meperidine. Furthermore, patient-controlled analgesia and sedation yielded a higher degree of patient satisfaction than continuous infusion of propofol/alfentanil (p = 0.0033) or nurse-administered midazolam/meperidine (p = 0.0094). CONCLUSIONS: Patient-controlled administration of propofol and alfentanil for colonoscopy may provide a better margin of safety than conventional administration of midazolam and meperidine and results in a higher level of patient satisfaction and shorter recovery.

Alfentanil↗
PubMed2000

Cost analysis of antibiotic prophylaxis for PEG.

BACKGROUND: There are conflicting recommendations regarding the prophylactic use of antibiotics in patients undergoing placement of percutaneous endoscopic gastrostomy tubes. The purpose of this decision analysis was to assess the cost-effectiveness of antibiotic prophylaxis in percutaneous endoscopic gastrostomy. METHODS: A decision tree was modeled using the data of 7 published prospective placebo-controlled trials. Infectious complications were classified as grade I (requiring local care), grade II (requiring intravenous antibiotics), or grade III (requiring surgery). Medication costs were estimated from the United States average wholesale prices of the 1998 Red Book. Physician and facility costs were estimated based on the 1998 Medicare costs. A one-way sensitivity analysis was performed by varying the probability rates of the complications associated with percutaneous endoscopic gastrostomy and the costs of their treatment. RESULTS: The average cost of prophylactic antibiotics was $13.10. Antibiotic prophylaxis led to expected cost savings of $76.72 per percutaneous endoscopic gastrostomy. A sensitivity analysis suggested that antibiotic prophylaxis for percutaneous endoscopic gastrostomy was the preferred strategy unless the average probability of grade III complications dropped below an improbably low threshold value of 0.09%. CONCLUSION: Antibiotic prophylaxis in percutaneous endoscopic gastrostomy is a cost-effective strategy.

Antibiotic Prophylaxis↗
PubMed2000

In-vivo real-time magnetic resonance monitoring of endoscopic laser applications in the porcine gastrointestinal tract.

BACKGROUND AND STUDY AIMS: Endoscopic laser therapy involves a risk of perforation, mainly because the depth of tissue destruction is not visible. Magnetic resonance (MR) imaging is capable of showing temperature changes, and is therefore suitable for monitoring thermal therapies such as laser. This animal study assessed the feasibility of real-time MR monitoring of endoscopic laser applications in the gastrointestinal tract. MATERIALS AND METHODS: The procedures were carried out using an MR-compatible endoscope in three live pigs in a 0.5-Tesla interventional MR system. Nd:YAG laser applications were performed in the lower gastrointestinal tract (n = 7) and upper gastrointestinal tract (n = 5), and were monitored using real-time color-coded T1-weighted gradient echo sequences. The postmortem macroscopic tissue coagulation sizes were compared with the lesion diameters seen on real-time MR. RESULTS: The endoscope did not cause any artifacts during continuous MR imaging. Ten of the twelve laser lesions were visible with temperature-sensitive MR imaging, and their sizes correlated well with the diameters of the postmortem macroscopic coagulation zones (r = 0.76, P = 0.009). Two laser lesions were not visible on MR due to technical limitations inherent with the healthy animal model. CONCLUSIONS: The formation of endoscopic laser lesions in the porcine gastrointestinal tract can be accurately visualized using real-time temperature-sensitive MR imaging. This new technique has the potential to spare healthy tissue while ensuring full treatment coverage of the targeted lesion with fewer therapy sessions.

Animals↗
PubMed2000

Transnasal versus transoral endoscopy for the placement of nasoenteral feeding tubes in critically ill patients.

BACKGROUND: Nasoenteral feeding tube placement with the Seldinger technique using transoral endoscopy is a tedious procedure. This study compared the transoral approach with a new technique that uses a transnasal endoscope without the need for a mouth-to-nose wire transfer. METHODS: Critically ill patients requiring nasoenteral feeding tube placement were randomly assigned to the transoral technique using a standard upper endoscope (n = 80) or the transnasal method using a 5.3 mm fiberscope (n = 80). Procedure time, medication requirement, technical difficulty, patient tolerance, and radiologic tube position were assessed. RESULTS: The two groups were similar with regard to baseline medication, endoscopic findings, as well as overall technical difficulty and patient tolerance. The transnasal technique required less procedure time (median 8.0 versus 12.0 minutes, p < 0.001) and less relaxant medication (p = 0.029). Furthermore, it caused fewer circulatory (p = 0.040) and respiratory (p = 0.016) alterations regardless of the application of sedative or relaxant medication. The transnasal endoscope was inferior with respect to passage through the pylorus (p = 0.003) and duodenum (p = 0.020). These differences were significant in univariate hypothesis testing. Bonferroni correction for multiple testing of data removed the significance at p > 0.0031. Both techniques achieved similar rates of successful tube placement in the small bowel (86% versus 84%, p = 0.82). CONCLUSION: Transnasal endoscopy allows accurate placement of nasoenteral feeding tubes in critically ill patients and is superior to transoral endoscopy in terms of procedure time, medication requirement, and safety.

Adult↗
PubMed1997

[Initial experiences with magnetic resonance endoscopy].

BACKGROUND: In contrast to endorectal surface coils used to assess pelvic tumors, the magnetic resonance endoscope (MR) has all the features of a standard endoscope. In ex-vivo imaging of the porcine gastrointestinal tract, endoscopic MR demonstrates distinct histological layers of the gastrointestinal wall. The aim of this study was to assess the feasibility and the accuracy of endoscopic MR in local staging of patients with esophageal and rectal cancer. METHODS: From April to August 1996, 12 patients (5 female and 7 male, mean age 63 [range 44-84] years) with histologically proven esophageal (n = 6) and rectal (n = 6) cancer prospectively underwent endoscopic ultrasound (EUS) followed by endoscopic MR. The two radiologists reviewing the endoscopic MR images were blinded to the EUS results. Assessment of T and N stages was compared to EUS and histology. RESULTS: Endoscopic MR was well tolerated in all patients and there were no complications. Image quality was sufficient in 75%. Endoscopic MR T-staging correlated with EUS and histology in 7/12 and 5/7 patients respectively. Discordance was due to overstaging by endoscopic MR. N-staging correlated with EUS and histology in 10/12 and 6/8 cases respectively. Non-correlation was due to a number of false negative results at endoscopic MR. CONCLUSION: These early results demonstrate endoscopic MR to be feasible and to produce comparable local staging to EUS in patients with esophageal and rectal cancer. The ultimate goal will be to combine endoscopic MR with body coil MR imaging (for the assessment of distant metastases) in order to provide "one-step staging" for the entire evaluation of gastrointestinal tumors.

Adult↗
PubMed1996

[Tumor staging and follow-up care in rectosigmoid carcinoma: colonoscopic endosonography compared to CT, MRI and endorectal MRI].

BACKGROUND AND STUDY AIMS: Endosonography has become the best available method for local staging of primary rectal cancer and diagnosing recurrent local tumor. The aim of this prospective study is to compare the accuracy of endoscopic ultrasound (EUS), using an echo colonoscope (CF-UM 3, CF-UM 20, Olympus optical) to computed tomography (CT), body coil magnetic resonance imaging (MRI) and endorectal coil magnetic resonance imaging (EMRI). PATIENTS AND METHODS: From February 1991 to July 1993 90 patients with primary rectosigmoidal tumors (n = 32: 9 women, 23 men, mean age 68 years [range 37 to 84]) or follow-up examinations for recurrent local cancer (patients: n = 58, examinations: n = 93; 41 women, 52 men, mean age 61 years [range 31 to 84]) were investigated. The results of preoperative examinations were compared to histopathological findings regarding T and N stages. RESULTS: In T staging, accuracy of EUS (78%) was superior to CT (50%) and equivalent to both MRI (75%) and EMRI (80%). The accuracy of EUS (84%) in assessing transmural tumor infiltration was superior to CT, MRT and EMRT (50%, 75% and 80%, resp.); however, CT (77%) and MRI (86%) were more accurate than EUS (64%) and EMRI (33%) in assessing N stages. Recurrent local cancer was found in 22 patients. All but one were detected by EUS. Sensitivity, specificity and accuracy in follow-up examinations for recurrent disease for EUS were 95%, 94% and 95%, for CT 75%, 73% and 74%, for MRI 57%, 100% and 70%, and for EMRI 83%, 100% and 90% resp. CONCLUSIONS: Endoscopic ultrasound proved to be a safe and accurate method of preoperative staging and early diagnosis of recurrent rectal cancer and was superior or at least equivalent to CT, MRI and EMRI.

Adult↗
PubMed1996

Compound motor action potential recording distinguishes differential onset of motor block of the obturator nerve in response to etidocaine or bupivacaine.

The purpose of this investigation was to establish an objective (quantitative) method for determining onset time of motor block induced by different local anesthetics. Twenty-four consenting patients undergoing transurethral surgery during spinal anesthesia were randomized to receive direct obturator nerve block with 10 mL of plain bupivacaine 0.5% (n = 12) or 10 mL of plain etidocaine 1% (n = 12). Another 14 patients (control group) received obturator nerve "block" with saline. After identification of the obturator nerve, patients underwent testing of nerve conduction by recording compound motor action potentials (CMAPs) of thigh adductor muscles in response to stimulation provided by a nerve stimulator at 0.2 to 0.5-mA currents. Testing ended when CMAP amplitudes had returned to their baseline values (control group) or when motor blockade was 90% complete (local anesthetic groups). In all 38 patients, the amplitude of the thigh CMAPs decreased immediately after injection of saline or local anesthetic. While CMAP amplitudes in the control group returned to their initial (baseline) values after 3-6 min, the patients receiving etidocaine or bupivacaine achieved > or = 90% motor blockade after 6 and 13 min, respectively. In the present report, the time to > or = 90% block was significantly faster in patients given etidocaine compared with those given bupivacaine. We conclude that electromyographic recording of CMAPs can be used to compare the ability of different local anesthetics to induce motor block.

Adult↗
PubMed1995

Electromyographic comparison of obturator nerve block to three-in-one block.

Obturator nerve block during spinal, epidural, or general anesthesia without muscle relaxants has been recommended for transurethral surgery to prevent thigh adductor muscle contractions during operative electrocautery. We investigated the effectiveness of direct obturator and 3-in-1 nerve motor blocks in 44 patients undergoing transurethral surgery during spinal anesthesia with isobaric bupivacaine. Patients were randomly assigned to receive 3-in-1 block with 40 mL (n = 13) or 50 mL (n = 11) of 1.5% lidocaine plus epinephrine, or direct obturator nerve block with 10 mL of 2% lidocaine plus epinephrine (n = 20). After both direct obturator and 3-in-1 blocks, compound muscle action potential (CMAP) testing of the obturator nerve was performed at 1-10-s intervals for 10 min. In patients given direct obturator nerve block (n = 20), CMAP amplitude decreased by 88.8 +/- 21% (mean +/- SD) from baseline. In contrast, 3-in-1 block reduced the evoked CMAP amplitude by 7.4 +/- 19% (P < 0.05). Peak lidocaine plasma levels of 1.6 +/- 0.2 micrograms/mL (range 1.0-2.8 micrograms/mL) were reached 60-90 min after the block in those patients receiving 50 mL of local anesthetic. The 3-in-1 technique fails to predictably result in effective motor block of the obturator nerve and thus may not prevent inadvertent thigh adductor muscle contractions during transurethral surgery. A direct approach to the obturator nerve is significantly more effective in producing motor block, and even when given in larger than recommended dosages it results in subtoxic peak plasma lidocaine concentrations.

Action Potentials↗
PubMed1990

[The significance of gamma-glutamyltransferase in the evaluation of the results of chemotherapy of liver metastasis].

The serum concentration of gamma-glutamyltransferase (gamma-GT) was serially measured in 26 cancer patients undergoing chemotherapy for liver metastases. 20 patients were studied retrospectively and 6 prospectively with emphasis on the first few days of cytostatic treatment. The gamma-GT determinations during the first days of treatment gave no indication of the prognosis of remission. Serial measurements during treatment do, however, serve to objectify the success of the chemotherapy. In most patients the gamma-GT concentrations paralleled the general condition as well as palpation and ultrasound examination of the liver. Direct interactions of cytotoxic drugs with gamma-GT could not be demonstrated. gamma-GT determinations are therefore of help in phase II studies in evaluating new drugs for their cytostatic activity against liver metastases.

Adult↗