[Factors of gastroesophageal acid reflux in severe obesity]. / Facteurs de reflux gastro-oesophagien acide dans l'obésité sévère.

OBJECTIVE: To study in morbid obesity the relationship between the degree of gastro-oesophageal reflux (GER) and the excess of body weight, or the related factors such as the energy intake or the fat distribution (waist-hip ratio). METHODS: In 20 morbid obese subjects (body weight: 125 +/- 32 kg) consulting in a weight-loss programme, anthropometric measurements, 3-hr oesophageal pHmetry, double isotope labelled meal for studying gastric emptying, study of gastric acid and pepsin secretions using PEG 4,000 as marker, and upper endoscopy were performed. RESULTS: Nine out of the 20 patients had more than 10 GER per 3-hr period. Seven patients had at least one GER symptom per day. In 6 patients, pH was under 4 for more than 10% of the time. The total number of GER and the number of GER of more than 5 min duration were correlated to the body mass index (P = 0.016 and P < 0.05 respectively). The number of GER was also correlated to the android type of overweight (P < 0.03). These relationships persisted when sex, age, smoking, and obesity complications (such as diabetes) were taken into account. There was a positive correlation between the number of GER and energy and lipid intake (energy intake: 3,119 +/- 1,082 kcal/day; P < 0.003 for both). The degree of GER was positively related to basal acid output (P = 0.049), and to sham feeding-stimulated acid output (P = 0.05); it was negatively related to gastric emptying half time, but was not correlated with basal or stimulated pepsin output. A relationship was found between body mass index (BMI) and gastric emptying half time for solid (P = 0.002) and liquid phases (P = 0.001). CONCLUSION: GER seems to be common in long lasting morbid obesity. The number of refluxes increased with waist/hip ratio, BMI and energy or fat intake. GER was also increased by decreased gastric emptying rate, which was in part determined by BMI. The real prevalence of GER in morbid obeses must be determined by a large prospective study.

Evaluation of the Technicon Dax 48: a multiparametric biochemical analyzer.

The Technicon Dax 48 system is a random access, selective, multitest, open reagent autoanalyzer with a capability of performing up to 34 analytes (32 colorimetric + two ISE). The Technicon Dax 48 has been evaluated over a 3-month period. Twenty-one blood parameters and seven urinary parameters have been studied including substrates, enzymes and electrolytes, according to the 'Valtec' protocol from the French Society for Clinical Biology (SFBC). Comparison for accuracy was done with results from our routine analyzer. Praticability has been evaluated by methodology adaptation and effective throughput checking. Quality for spectrophotometer and temperature control is in agreement with required criteria. The overall design of the system, one sample, one flow cell, one reagent line and nozzle, one specific hydraulic circuit per analytical method, avoids, de facto, any contamination. Result analysis and interpretation show excellent analytical performance (precision, accuracy, analytical range). For the evaluated methods, 85% of the coefficients of variation are under 2%. Sample sizes of 500-microliters are hardly compatible with pediatric samples. There are many advantages when using Dax 48: blood and urine samples can be accommodated at random and the superior quality of electrodes guarantees 20,000 tests. Automated procedures for start up, shut down, maintenance and an effective throughput 1.5 higher than our current routine analyzer's (comparison system) makes Dax 48 more appropriate to handle a large workload. User-friendly software, ease of use and analytical performances make the Dax 48 system suitable for institutions with a large workload.