PubMed Health⌕ Search

Biomedical subjects

T G Wenzl

Publications and source records attributed to T G Wenzl.

13 recordsLinked to original sources

Effect of Gaviscon Infant on gastro-oesophageal reflux in infants assessed by combined intraluminal impedance/pH.

BACKGROUND: Gaviscon Infant (GI) has been recommended for gastro-oesophageal reflux (GOR) in infants. Its efficacy has not been examined with a physiologically appropriate denominator to define the degree of GOR. AIM: To investigate the influence of Gaviscon Infant on GOR in infants using combined pH and intraluminal impedance measurement. METHODS: Twenty infants (mean age 163.5 days, range 34-319 days) exclusively bottle fed, with symptoms clinically suggestive of GOR, underwent 24 hour studies of intra-oesophageal 6 channel impedance and dual channel pH monitoring, during which six random administrations (3+3) of Gaviscon Infant (625 mg in 225 ml milk) or placebo (mannitol and Solvito N, 625 mg in 225 ml milk) were given in a double blind fashion. Impedance/pH reflux data were recorded and analysed blind by one observer. RESULTS: The median number of reflux events/hour (1.58 v 1.68), acid reflux events/hour (0.26 v 0.43), minimum distal or proximal pH, total acid clearance time per hour (time with pH below pH 4), and total reflux duration per hour were not significantly different after GI than after placebo. Reflux height was marginally lower after GI (median 66.6% v 77.3% oesophageal length) compared with placebo. CONCLUSIONS: Results showed a marginal but significant difference between Gaviscon Infant and placebo in average reflux height, and raises questions regarding any perceived clinical benefit of its use.

Alginates↗

Association of apnea and nonacid gastroesophageal reflux in infants: Investigations with the intraluminal impedance technique.

An association of apnea and gastroesophageal reflux (GER) was proposed previously. However, pH metry as the standard diagnostic tool for GER only measures acid reflux (pH < 4). It is difficult to interpret studies in infants with a presumed association between apnea and GER based on pH metry because the buffering effect of feeding may result in predominantly nonacid GER. The aim of this study was to investigate the temporal association of apnea and GER with the pH-independent intraluminal impedance technique (IMP). Infants with recurrent regurgitation or respiratory symptoms suggestive of apnea were investigated simultaneously with IMP, pH monitoring, and polygraphy. IMP patterns, pH, oronasal flow, and chest wall movement were recorded and analyzed. In 22 infants, 364 GER episodes were recorded by IMP. One hundred and sixty five apneas were documented by visual validation of polygraph records. Forty-nine apneas (29.7%) were associated with GER; 11 (22.4%) of these showed acid reflux (pH < 4). A significant correlation between the time spent apneic and GER was found (P < 0.001). There is marked association between apnea and gastroesophageal reflux in infants. Patients potentially at risk cannot be reliably identified by pH metry. Its exclusive use is therefore not suitable for the detection of all GER-associated apneas in infants. The pH-independent intraluminal impedance technique has proven to be a sensitive diagnostic tool for this approach.

Apnea↗

Intraluminal impedance: an ideal technique for evaluation of pediatric gastroesophageal reflux disease.

Gastroesophageal reflux (GER) in infants becomes gastroesophageal reflux disease (GERD) through association with distinct clinical symptoms. Monitoring of pH is considered the standard diagnostic tool through which episodes of acidity can be detected. Apparently, however, the major amount of GER occurs in the physiologic esophageal pH range, which is concealed to pHmetry. Intraluminal impedance is a new method for pH-independent detection of esophageal bolus movement. Long-term measurements and combination with other diagnostic methods, e.g., pHmetry or polygraphic recordings, are possible. Intraluminal impedance has proved especially useful in diagnosing GER and GERD in infants. It may develop into the ideal technique for this group of patients.

Electric Impedance↗

Procedure for the semi-automatic detection of gastro-oesophageal reflux patterns in intraluminal impedance measurements in infants.

The diagnosis of gastro-oesophageal reflux (GOR) is of great interest for paediatric gastroenterologists. pH monitoring is the commonly used procedure for GOR diagnosis but a major amount of postprandial GOR is missed due to the mostly non-acidic gastric contents in infants. The multiple intraluminal impedance technique is based on the recording of the impedance changes during bolus transport inside the oesophagus. It is the first method which allows the pH-independent, long-term registration of GOR. The use of the impedance technology in clinical practice has been limited so far by the time-consuming, visual evaluation of the impedance traces. The new approach of a semi-automatic analysis of the impedance measurements allows the automated detection of reflux patterns. It is based on event marking and an optimised feature description of the impedance traces combined with a fuzzy system for pattern recognition. The classifier is developed and tested on 50 investigations in infants. Compared to the comprehensive, multiple visual evaluation the achieved precision is 75% sensitivity and 48% positive prediction. In comparison to a single visual evaluation the analysis of the automatically proposed patterns corresponds to a 96% reduction of the evaluation time with no loss of precision. Thus the applicability of the impedance technology is enhanced significantly. A combined measurement of pH and impedance gives evidence about the occurrence of GOR, its pH and the acidic exposure of the oesophagus.

Algorithms↗

Gastroesophageal reflux and respiratory phenomena in infants: status of the intraluminal impedance technique.

BACKGROUND: The coincidence of recurrent respiratory symptoms and gastroesophageal reflux (GER) is a well-known phenomenon in infants. Twenty-four-hour pH metry is the presumed gold standard of diagnostic tools for this symptom complex, but with this method, only acid (pH <4) and alkaline (pH >7) GER can be detected. Gastroesophageal reflux with an esophageal pH in the physiological range (pH 5-6.8) may represent many cases of clinically relevant GER unrecognized by pH metry. In this study the intraluminal multiple electrical impedance (IMP) procedure for complete registration of GER was compared with pH metry for its diagnostic value in the presence of respiratory symptoms. METHODS: Twenty-two infants with recurrent regurgitation or pulmonary problems were investigated simultaneously with IMP, pH metry, and polygraphy during two feeding periods. Heart rate, oxygen saturation, sleep states, and oronasal flow were recorded, among other parameters. RESULTS: Three hundred sixty-four occurrences of GER were detected by IMP; only 11.4% had a pH less than 4 and were therefore recognized by pH metry. Three hundred twelve (84.8%) occurrences were associated with breathing abnormalities, and 11.9% of these were detected by pH metry. Nineteen instances were accompanied by a decrease of oxygen saturation of more than 10% of the initial value. Only three (15.8%) of these had a pH less than 4. The remaining 16 reflux episodes were recognized by IMP only. After software-aided preselection, 165 instances of apnea were visually validated, 49 of which were accompanied by GER. Thirty-eight (77.6%) of these were exclusively recorded by IMP. CONCLUSIONS: The use of pH metry alone cannot detect most GER incidents accompanied by respiratory symptoms and therefore does not appear to be suitable for this approach. The pH-independent IMP technique promises to be a reliable tool for presumably GER-associated respiratory symptoms.

Electric Impedance↗

Pharmacokinetics of oral fluconazole in premature infants.

UNLABELLED: Systemic infections with Candida albicans in neonates are a frequent and well recognized problem. The therapeutic gold standard in this situation is the combined intravenous antimycotic treatment with amphotericin B and flucytosine. Potential adverse effects of this regimen have encouraged the search for desirable alternatives. We report on the use of oral fluconazole in neonates with Candida albicans septicaemia. Three premature infants were treated with four courses of therapy. Pharmacokinetic studies were performed during each course. At oral doses of 4.5-6 mg/kg once a day, serum levels of fluconazole were within the therapeutic range during the entire dosage interval. Follow up showed microbiological and clinical cure in all patients with no side-effects. In one patient a dosage of 4 mg/kg per day lead to a microbiological relapse with sub-therapeutic serum levels. CONCLUSIONS: Oral fluconazole seems to be a safe and effective treatment for Candida albicans septicaemia even in premature infants.

Administration, Oral↗