The association between iron deficiency and outcomes: a secondary analysis of the intravenous iron therapy to treat iron deficiency anaemia in patients undergoing major abdominal surgery (PREVENTT) trial

In the intravenous iron therapy to treat iron deficiency anaemia in patients undergoing major abdominal surgery (PREVENTT) trial, the use of intravenous iron did not reduce the need for blood transfusion or reduce patient complications or length of hospital stay. As part of the trial protocol, serum was collected at randomisation and on the day of surgery. These samples were analysed in a central laboratory for markers of iron deficiency. We performed a secondary analysis to explore the potential interactions between pre-operative markers of iron deficiency and intervention status on the trial outcome measures. Absolute iron deficiency was defined as ferritin <30 μg.l^-1 ; functional iron deficiency as ferritin 30-100 μg.l^-1 or transferrin saturation < 20%; and the remainder as non-iron deficient. Interactions were estimated using generalised linear models that included different subgroup indicators of baseline iron status. Co-primary endpoints were blood transfusion or death and number of blood transfusions, from randomisation to 30 days postoperatively. Secondary endpoints included peri-operative change in haemoglobin, postoperative complications and length of hospital stay. Most patients had iron deficiency (369/452 [82%]) at randomisation; one-third had absolute iron deficiency (144/452 [32%]) and half had functional iron deficiency (225/452 [50%]). The change in pre-operative haemoglobin with intravenous iron compared with placebo was greatest in patients with absolute iron deficiency, mean difference 8.9 g.l^-1 , 95%CI 5.3-12.5; moderate in functional iron deficiency, mean difference 2.8 g.l^-1 , 95%CI -0.1 to 5.7; and with little change seen in those patients who were non-iron deficient. Subgroup analyses did not suggest that intravenous iron compared with placebo reduced the likelihood of death or blood transfusion at 30 days differentially across subgroups according to baseline ferritin (p = 0.33 for interaction), transferrin saturation (p = 0.13) or in combination (p = 0.45), or for the number of blood transfusions (p = 0.06, 0.29, and 0.39, respectively). There was no beneficial effect of the use of intravenous iron compared with placebo, regardless of the metrics to diagnose iron deficiency, on postoperative complications or length of hospital stay.

Research Article. The Influence of Some Parameters on Chiral Separation of Ibuprofen by High-Performance Liquid Chromatography and Capillary Electrophoresis

Objective: The aim of the study was to compare the influence of mobile phase composition and temperature on chiral separation of racemic ibuprofen by capillary electrophoresis and high performance liquid chromatography with UV detection. Materials and methods: Racemic ibuprofen was analysed on a chiral OVM column with an HPLC system 1100 Agilent Technologies, under isocratic elution, by using potassium dihydrogen phosphate 20 mM and ethanol in mobile phase. The flow rate was set at 1 mL/min, UV detector at 220 nm and different column temperatures were tested. For electrophoresis separation an Agilent CE G1600AX Capillary Electrophoresis System system, with UV detection, was used. The electrophoresis analysis was performed at different pH values and temperatures, with phosphate buffer 25 mM and methyl-β-cyclodextrin as chiral selector. Results: The chromatograhic analysis reveals a high influence of mobile phase pH on ibuprofen enantiomers separation. An elution with a mixture of potassium dihydrogen phosphate 20 mM pH=3 and ethanol, at 25°C, allowed enantiomers separation with good resolution in less than 8 min. Conclusions: The proposed HPLC method proved suitable for the separation of ibuprofen enantiomers with a good resolution, but the capillary electrophoresis tested parameters did not allow chiral discrimination.

[Results of laparoscopic repair of abdominal wall hernias using an ePTFE-polypropylene composite mesh]

BACKGROUND

The standard technique for laparoscopic ventral hernioplasty (peritoneal onlay) reduces the recurrence rate and the rate of other complications, in particular the risk of infections. However, the procedure requires a special mesh to mitigate the risk of visceral adhesions. For this purpose an ePTFE mesh is generally used. There are limited reported clinical data regarding the long-term results and benefits of other biomaterials.

STUDY DESIGN

Bard Composix mesh was used for laparoscopic ventral hernia repair. This biomaterial combines two different clinically proven materials--polypropylene with a thin layer of ePTFE--to maximize ingrowth of surrounding tissue, while mitigating the risk of visceral adhesions. Demographic, operative and postoperative data were collected and analyzed. Follow-up clinical evaluations were conducted 6-10 days, 4 weeks, and every 6 (th) month after surgery in all patients.

RESULTS

Fifteen patients were involved in the study. The mean operating time was 101.2 min (64-190 min). There were no intraoperative complications or conversion to open procedure. Postoperative complications were 1 seroma, 4 cases of prolonged ileus, one tacks-site pain requiring second-look laparoscopy. Hospital discharge occurred on average 6 days (3-10 days) after surgery. The mean follow-up was 12.4 months (range 5-29 months). No late complications or hernia recurrence were observed.

CONCLUSIONS

Laparoscopic prosthetic ventral hernioplasty using the composite polypropylene/ePTFE mesh offers short hospital stay and acceptable complications for primary and recurrent ventral hernias. Disadvantage of the composite mesh is the difficulty to roll this product into a sufficiently small size to permit its easy introduction into the abdominal cavity.

Transcutaneous electrogastrography: a non-invasive method to evaluate post-operative gastric disorders?

BACKGROUND/AIMS

With the development of high-performance computer programs, transcutaneous electrogastrography has experienced a renaissance in the last few years and is widely recommended as a non-invasive diagnostic tool to evaluate functional gastric disorders. We assessed the clinical value of electrogastrography in symptomatic and asymptomatic patients after a variety of procedures of the upper gastrointestinal (GI) tract.

METHODOLOGY

Electrogastrography tracings were recorded with a commercially available data logger using a recording frequency of 4 Hz. A standard meal was given between a 60 min preprandial and a 60 min postprandial period. The following parameters were analyzed pre- and postprandially utilizing Fourier and spectral analysis: Regular gastric activity (2-4 cycles/minute), bradygastria (0.5-2 cycles/minute), tachygastria (4-9 cycles/minute), dominant frequency and power of the dominant frequency. Nineteen asymptomatic healthy volunteers served as a control group. Forty-nine patients, who had undergone upper intestinal surgery, were included in the study (cholecystectomy n = 10, Nissen fundoplication n = 10, subtotal gastrectomy n = 8, truncal vagotomy, and gastric pull-up as esophageal replacement n = 6). Twenty of these patients complained of epigastric symptoms post-operatively, while 12 of these 20 patients also had a scintigraphic gastric emptying study with Tc99m labeled semisolid meal.

RESULTS

Preprandial gastric electric activity was between 2 and 4 cycles/minute in 60-90% of the study time in healthy volunteers. In all study groups the prevalence and power of normal electric activity increased significantly after the test meal (p < 0.001). After cholecystectomy, Nissen fundoplication, subtotal gastrectomy or vagotomy and gastric pull-up pre- and postprandial gastric electric activity showed a greater variability compared to normal volunteers (p < 0.05), but no typical electrogastrography pattern could be identified for the different surgical procedures. There was no significant difference in the electrogastrography pattern between asymptomatic and symptomatic patients and patients with normal or abnormal scintigraphic gastric emptying curves.

CONCLUSIONS

There is no specific electrogastrography pattern to differentiate between typical surgical procedures or epigastric symptoms. To date, electrogastrography does not contribute to the diagnosis and analysis of gastric motility disorders after upper intestinal surgery.