Circulating Oxalate Levels in Short Bowel Syndrome as a Severity Marker of CKD.

Introduction: Patients with short bowel syndrome (SBS) may exhibit enteric hyperoxaluria (EH), and the prevalence of oxalate nephropathy in SBS is likely underestimated. Plasma oxalate (POx) is a surrogate of systemic oxalate deposition and, consequently, may increase the risk of developing chronic kidney disease (CKD). The main objective of this study was to explore the distribution of POx levels in patients with SBS. Methods: Patients followed for SBS were recruited prospectively in the OXAGO study (NCT04119765) to assess POx during their annual renal follow-up including iohexol clearance. The inclusion criteria were age ≥18 years, and SBS type 2 and type 3 for more than 6 months. Results: A total of 47 patients were included but only 45 patients has a measured POx (55% males, 80% SBS type 2, 66% parenteral nutrition, 61% kidney stone history). POx levels were 6.8 ± 4.4 µmol/l, 29% of patients had POx ≥5 µmol/l. In the whole cohort, mean urinary oxalate (UOx) was 648±415 and 54% were >500 µmol/24h. In the group of patients with high POx levels (HPO), 24-hour urine oxalate was significantly higher than in the group with normal POx levels (NPO) (919 ± 566 vs. 526 ± 257 µmol/l; P = 0.003). Glomerular filtration rate (GFR) was 66 ± 22 ml/min per 1.73 m2, and 91% had CKD. GFR was significantly lower in the HPO than in the NPO group (49 ± 23 vs. 73 ± 18 ml/min per 1.73 m2; P = 0.0005. Conclusion: Patients with SBS can display increased POx levels even with GFR >30 ml/min per 1.73 m2. POx may be an interesting biomarker to assess the severity of EH.

Oxalate: from physiology to pathology / Oxalate : de la physiologie à la pathologie

Hyperoxaluria is defined by an increase of urinary oxalate, leading to kidney stones, nephrocalcinosis and/or chronic kidney disease. There are different diseases related to hyperoxaluria: (1) kidney stones, 50% of them being explained by intermittent hyperoxaluria, secondary to dietary mistakes such as low hydration, excess of oxalate consumption and/or low calcium consumption; (2) primary hyperoxaluria, a genetic orphan disease inducing a massive production of oxalate by the liver, leading to increased plasma oxalate increase and saturation, and further systemic oxalosis with oxalate deposition, nephrocalcinosis and ultimately kidney failure, the management of this disease being currently dramatically modified by the onset of new therapeutic tools such as RNA interference; and (3) enteric hyperoxaluria, resulting from increased intestinal oxalate absorption because of intestinal malabsorption (short bowel syndrome, bariatric surgery, exocrine pancreatic insufficiency, etc.). Diagnosis and therapeutic management of these diseases require a full understanding of oxalate physiology that we detail in this review.

L'hyperoxalurie, définie par une élévation de l'oxalate urinaire, favorise la survenue d'une maladie lithiasique, d'une néphrocalcinose et/ou d'une insuffisance rénale chronique. L'hyperoxalurie peut témoigner de différentes maladies : (1) l'hyperoxalurie diététique, responsable de 50 % de la maladie lithiasique par le biais d'erreurs alimentaires (hydratation insuffisante, consommation excessive d'oxalate et/ou consommation insuffisante de calcium) ; (2) les hyperoxaluries primaires, maladies génétiques orphelines responsables d'une production massive d'oxalate aboutissant à des dépôts tissulaires précoces (dès l'enfance) et sévères (à l'origine d'une insuffisance rénale terminale puis d'une thésaurismose avec atteinte multiviscérale) et dont le pronostic est aujourd'hui transformé par les nouvelles thérapies (ARN interférents) ; (3) l'hyperoxalurie entérique, résultant d'une augmentation de l'absorption digestive de l'oxalate dans une situation de malabsorption (syndrome du grêle court, chirurgie bariatrique, insuffisance pancréatique exocrine, etc.). La physiologie de l'oxalate, détaillée dans cet article, permet d'appréhender la prise en charge diagnostique et thérapeutique de ces maladies.

Climate-smart Actions in the Operating Theatre for Improving Sustainability Practices: A Systematic Review.

CONTEXT: Surgical activity contributes to global warming though the production of greenhouse gases and consumption of resources. To date, no clinical practice guidelines have been made to promote and implement climate-smart actions. OBJECTIVE: To perform a systematic review of the available actions that could limit CO2 emission in the operating room (OR) and their potential benefits upon the environment, whilst preserving quality of care. EVIDENCE ACQUISITION: MEDLINE and Cochrane databases were searched from January 1, 1990 to April 2021. We included studies assessing carbon footprint (CF) in the OR and articles detailing actions that limit or reduce CF. EVIDENCE SYNTHESIS: Thirty-eight studies met the inclusion criteria. We identified six core climate-smart actions: (1) waste reduction by segregation; (2) waste reduction by recycling, reuse, and reprocessing; (3) sterilisation; (4) anaesthesia gas management; and (5) improvement of energy use. Quantitative analysis regarding the CF was not possible due to the lack of homogeneous data. For climate-smart actions, the analysis was limited by discrepancies in study scope and in the methodology of CO2 emission calculation. Improvement of education and awareness was found to have an important impact on waste segregation and reduction. Waste management is the area where health care workers could have the strongest impact, whereas the main field to reduce CF in the OR was found to be energy consumption. CONCLUSIONS: This review provides arguments for many climate-smart actions that could be implemented in our daily practice. Improving awareness and education are important to act collectively in a sustainable way. Further studies are mandatory to assess the impact of these climate-smart actions in the OR. PATIENT SUMMARY: We performed a systematic review of the available scientific literature to reference all the climate-smart actions proposed to improve the sustainability of surgical activities. Waste segregation, waste reduction and recycling, reuse and reprocessing, sterilisation, anaesthesia gas changes, and improvement of energy use in the operating room were found to be the main areas of research. There is still a long way to go to homogenise and improve the quality of our climate-smart actions.

Pulmonary Effects of Sustained Periods of High-G Acceleration Relevant to Suborbital Spaceflight.

AbstractBACKGROUND: Members of the public will soon be taking commercial suborbital spaceflights with significant Gx (chest-to-back) acceleration potentially reaching up to 6 Gx. Pulmonary physiology is gravity-dependent and is likely to be affected, which may have clinical implications for medically susceptible individuals.METHODS: During 2-min centrifuge exposures ranging up to 6 Gx, 11 healthy subjects were studied using advanced respiratory techniques. These sustained exposures were intended to allow characterization of the underlying pulmonary response and did not replicate actual suborbital G profiles. Regional distribution of ventilation in the lungs was determined using electrical impedance tomography. Neural respiratory drive (from diaphragm electromyography) and work of breathing (from transdiaphragmatic pressures) were obtained via nasoesophageal catheters. Arterial blood gases were measured in a subset of subjects. Measurements were conducted while breathing air and breathing 15 oxygen to simulate anticipated cabin pressurization conditions.RESULTS: Acceleration caused hypoxemia that worsened with increasing magnitude and duration of Gx. Minimum arterial oxygen saturation at 6 Gx was 86 1 breathing air and 79 1 breathing 15 oxygen. With increasing Gx the alveolar-arterial (A-a) oxygen gradient widened progressively and the relative distribution of ventilation reversed from posterior to anterior lung regions with substantial gas-trapping anteriorly. Severe breathlessness accompanied large progressive increases in work of breathing and neural respiratory drive.DISCUSSION: Sustained high-G acceleration at magnitudes relevant to suborbital flight profoundly affects respiratory physiology. These effects may become clinically important in the most medically susceptible passengers, in whom the potential role of centrifuge-based preflight evaluation requires further investigation.Pollock RD, Jolley CJ, Abid N, Couper JH, Estrada-Petrocelli L, Hodkinson PD, Leonhardt S, Mago-Elliott S, Menden T, Rafferty G, Richmond G, Robbins PA, Ritchie GAD, Segal MJ, Stevenson AT, Tank HD, Smith TG. Pulmonary effects of sustained periods of high-G acceleration relevant to suborbital spaceflight. Aerosp Med Hum Perform. 2021; 92(7):633641.

Holmium Laser Enucleation of the Prostate versus Laparoscopic Transcapsular Prostatectomy: Perioperative Results and Three-Month Follow-Up.

PURPOSE: Symptomatic benign prostatic hypertrophy greater than 70 cc used to be treated by invasive procedures. Holmium laser enucleation of prostate (HoLEP) and laparoscopic transcapsular prostatectomy (LTP) are two techniques whose efficacy has been demonstrated compared to standard onesmore invasive standard procedures. The objective was to evaluate and compare perioperative results from these two techniques for the treatment of benign prostatic hypertrophy greater than 70 cc. METHODS: This was a non-randomized retrospective study comparing the HoLEP technique with LTP. From January 2012 to January 2015, 39 patients had HoLEP and 28 had LTP. Perioperative outcomes, complications, and functional results at 3 months were compared. A chi-2 squared test and Student's t test were used for statistical analysis. RESULTS: In multivariate analysis, there was a statistically significant difference in favor of HoLEP for the duration of catheterization (1.9 vs. 3.7 days; p = 0.004) and the average length of stay (2.8 vs. 4.0 days, p = 0.010). There was a trend towards a greater decrease in postoperative hemoglobin levels in LTP (138 vs. 218 g/l; p = 0.082), which was statistically significant in univariate analysis (p = 0.033). Other endpoints were not significant, particularly the enucleated prostate volume compared to the total prostate volume (61.8 vs. 68.4%; p = 0.319) and postoperative complications. CONCLUSION: There was no increased morbidity for LTP compared to the HoLEP technique. However, the HoLEP technique appeared to be a less invasive technique, reducing the duration of catheterization, blood loss, and the average length of stay while maintaining good efficacy for the enucleated prostate volume.

Decreased Radiation Exposure and Increased Efficacy in Extracorporeal Lithotripsy Using a New Ultrasound Stone Locking System.

PURPOSE: To compare fluoroscopy duration, radiation dose, and efficacy of two ultrasound stone localization systems during extracorporeal shockwave lithotripsy (SWL) treatment. PATIENTS AND METHODS: Monocentric prospective data were obtained from patients consecutively treated for renal stones using the Sonolith(®) i-sys (EDAP TMS) lithotripter, with fluoroscopy combined with ultrasound localization using an "outline" Automatic Ultrasound Positioning Support (AUPS) (group A), or the "free-line" Visio-Track (VT) (EDAP-TMS) hand-held three-dimensional ultrasound stone locking system (group B). Efficacy rate was defined as the within-groups proportion stone free or with partial stone fragmentation not needing additional procedures. Statistical analysis used Pearson chi-square tests for categoric variables, nonparametric Mann-Whitney tests for continuous variables, and linear regression for operator learning curve with VT. Continuous variables were reported as median (range) values. RESULTS: Patients in group A (n=73) and group B (n=81) were comparable in baseline characteristics (age, kidney stone size, others) and in SWL application (duration, number of shocks, energy [Joules]). During SWL, the median (range) duration (seconds) of radiation exposure was 159.5 (0-690) in group A and 3.5 (0-478) in group B (P<0.001) and irradiation dose (mGy.cm(2)), 10598 (0-54843) in group A and 163 (0-13926) in group B (P<0.001). Fluoroscopy time significantly decreased with operator experience using VT. The efficacy rate was 54.5% in group A and 79.5% in group B (P=0.001). CONCLUSION: VT significantly reduced fluoroscopy use during SWL and the duration and dose of patient exposure to ionizing radiation. Stone treatment efficacy was significantly greater with VT mainly because of a better real-time monitoring of the stone.

Complications after artificial urinary sphincter implantation in patients with or without prior radiotherapy.

OBJECTIVE: To compare complications after implantation of an artificial urinary sphincter (AUS) in patients with or without prior radiotherapy (RT). PATIENTS AND METHODS: Between January 2000 and December 2011, 160 patients underwent AMS 800 AUS implantation in our institution. We excluded neurological and traumatic causes, implantation on ileal conduit diversion, penoscrotal urethral cuff position and those lost to follow-up. In all, 122 patients were included in the study, 61 with prior RT and 61 without prior RT. All patients underwent the same surgical technique by two different surgeons. All AUS were implanted with a bulbar urethral cuff position. The mean (range) follow-up was 37.25 (1-126) months. RESULTS: In the patients without prior RT and those with prior RT, revision rates were 32.8% vs 29.5%, respectively (P = 0.59). The median time to first revision was 11.7 months. Early complications were similar in the two groups (4.9% vs 6.5%, P = 1). Erosion rates were not significantly different (4.9% vs 13.1%, P = 0.13). However, infection and explantation were more prevalent in patients with prior RT [two (3.2%) vs 10 (16.3%), P = 0.018 and three (4.9%) vs 12 (19.6%), P = 0.016, respectively]. Finally, continence rates were not significantly different [75.4% (without prior RT) vs 63.9% (with prior RT), P = 0.23]. CONCLUSION: AUS is the 'gold standard' treatment of male urinary incontinence after re-education failure in patients with or without prior RT. Our experience showed similar functional outcomes in both groups but a higher rate of major complications in the group with prior RT.