Relever les défis environnementaux pour les filières cotonnières d'Afrique de l'Ouest et du Centre

Taking up the environmental challenges of the cotton production and marketing chains in Western and Central Africa.The extension of cotton cultivation in Western and Central Africa involves negative consequences for the environment on thelevel of the climatic changes, the reduction of biological diversity and the acceleration of desertifi cation. In addition to the fallof wooded areas and the death of various animals related to the use of pesticides, it appears that the current production practicesare at the origin of the degradation of the soil fertility through erosion and accelerated mineralization of the organic matter.Being given the major socio-economic importance of the cotton crop in the farming systems of these areas, it is essential toevolve to systems that are at the same time more sustainable and more productive. The achievement of this objective impliesdrastic changes on several levels in the operation of the cotton agrarian systems. These changes concern mainly the applicationof anti-erosive techniques and the restoration/improvement of the soil organic content. With this intention, the introductionof the tree into the agrarian systems and a true integration of agriculture and animal breeding in order to produce and usemore organic manure appear impossible to circumvent. In the long term, the development cropping system under permanentvegetable cover seems to be the technical solution best adapted to the problems of erosion and fall of the soil organic mattercontent; these systems allow indeed a stabilization and a durable improvement of the yields and should favour the applicationof intensifi ed practices regarding the integration of agriculture and animal breeding. The application of these new techniquesimplies important changes on the level of the natural resources management in order to guarantee a right remuneration of the investments made by the producers in terms of land improvements (installation of hedges, windshield, permanent vegetablecover, etc.) and to avoid the negative impact on the produced biomass of the animal divagation and bush fi res. This supposesactions on the level of the land security of the producers, management of the bush fi res and resolution of the potential confl ictsbetween farmers and transhumant stockbreeders. The profi tability of the cotton systems also depends on an effective controlat the best cost of the pests to face the development of resistances to pesticides (in particular to pyrethrinoids). The solution bythe genetically modifi ed plants is the subject of debates with different attitudes from a country to another. The possible answersto take up the environmental challenges to which the cotton production and marketing chains are confronted are discussed inthe present communication

Production de biomasse de Brachiaria ruziziensis (Germain et Evrard) en vue de la mise en place de systèmes de culture sous couvertures végétales dans la zone cotonnière du Cameroun

Résumé Les systèmes de culture sous couvertures végétales vulgarisés dans la zone cotonnière du Nord Cameroun reposent sur la production en première année de fortes biomasses sur lesquelles sont installées les cultures subséquentes. La présente étude avait pour objectif d’évaluer la production de biomasse de l’espèce Brachiaria ruziziensis en tête de rotation dans les systèmes de culture de la zone cotonnière du Cameroun, en présence des fumures organique et minérale recommandées. La production moyenne de biomasse de l’espèce B. ruziziensis a été significativement différente entre les sites de Guiring, Djalingo et Touboro au Nord, au Centre et au Sud de la zone cotonnière, respectivement. Le site de Touboro a été le plus productif (20,2 t MS ha-1), suivi de Guiring (11,7  t MS ha-1) et Djalingo (8,6  t MS ha-1). Les quantités de biomasse ainsi obtenues sont suffisantes pour l’installation des systèmes de culture sous couverture végétale l’année subséquente. Les différences observées entre les sites recommandent une évaluation de leur potentiel de production de biomasse avant la mise en place des systèmes de culture vulgarisés. La fertilisation recommandée devrait être maintenue, bien qu’elle soit générale pour l’ensemble des graminées, en attendant que des essais pour la détermination des doses optimales utilisant une gamme plus étendue de nutriments soient effectués. Mots clés: Agriculture de conservation, Plante de couverture, Brachiaria ruziziensis,  biomasse.   Abstract Direct seeding mulch-based cropping systems that have been recently introduced in Northern Cameroon recommend sowing cover crops in the first year of rotations which are followed by subsequent crops of interest. The objective of this study was to evaluate the seeding year biomass production of Brachiaria ruziziensis in the cotton producing zone of Cameroon, under recommended organic and mineral fertilizer rates. Biomass production of B. ruziziensis was significantly different among the experimental sites. The highest dry matter yield was recorded in Touboro (20.2 t DM ha-1), followed by Guiring (11.7 t DM ha-1) and Djalingo (8.6 t DM ha-1), stations located to the South, North and Centre of the cotton production zone, respectively. These biomasses are enough for the implementation of direct seeding mulch-based cropping systems. The differences observed among sites suggest their evaluation for biomass production before the use of such systems. Though common to all grasses, the present fertilizer recommendations should be maintained but further work is needed for the determination of optimal fertilizer recommendations using a more extended nutrient scale. Key words: Conservation agriculture, Cover crop, Brachiaria ruziziensis, biomass

Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

© 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

© 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research

Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries

Background Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks. Methods The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned. Results A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P &lt; 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31). Conclusion Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)