Mechanical ventilation in intensive care unit: What needs to be known in 2017

International audienc

Chenier-type ridges in Giralia Bay (Exmouth Gulf, Western Australia) - processes, chronostratigraphy, and significance for recording past tropical cyclones

Past coastal flooding events may be inferred from geomorphic and sedimentary archives, including particular landforms (e.g., beach ridges, washover fans), deposits (e.g., washover sediments in lagoons) or erosional features (e.g., erosional scarps within strandplains). In Giralia Bay, southern Exmouth Gulf (Western Australia), sandy ridge sequences in supratidal elevations form the landward margin of extensive mudflats. The formation of these ridges is assumed to be mainly driven by tropical cyclones (TCs), although their depositional processes need to be clarified. We investigated the supratidal sandy ridge sequence in Giralia Bay by carrying out process monitoring, geomorphological mapping by means of an unmanned aerial vehicle survey, as well as sedimentological and geochronological investigations and multivariate statistics. Based on the resulting data, this study aims at (i) identifying the most important driving processes to form the sandy ridges; (ii) establishing their chronostratigraphy; and (iii) understanding their significance for recording past TC activity. Trench excavations revealed sandy units that are interbedded with mud layers at the base, similar to the present distal mudflat sediments. On top, mud intercalations recede, and sand layers of varying grain size distribution dominate. In the upper part of the trenches, younger sediment layers onlap older ones documenting the stepwise seaward accretion of the ridges onto the mudflat. While our data suggests that tidal processes have only limited effects on ridge activity, sediment transport, erosion and deposition seems to be driven by both TC-induced storm surges and high magnitude precipitation events causing surface discharge. Most accretionary sand units are thus assumed to represent events of morphodynamic activity during TC-induced flooding since the mid-Holocene. Ridge activity is recorded in a roughly decadal resolution and over historical as well as prehistorical/Holocene time scales. While the ridges do not represent beach or chenier ridges sensu stricto, they may be described as chenier-type ridges due to their stratigraphical architecture. Ridge evolution, however, over a millennial time scale seems to be indicated by the landward rise of the sequence possibly corresponding to the mid-Holocene sea-level highstand of Western Australia of at least 1–2 m above present mean sea level

The intensive care medicine agenda on acute kidney injury

SMB is supported by a Canada Research Chair in Critical Care Nephrology

Epidemiology of surgery associated acute kidney injury (EPIS-AKI): a prospective international observational multi-center clinical study

Purpose: The incidence, patient features, risk factors and outcomes of surgery-associated postoperative acute kidney injury (PO-AKI) across different countries and health care systems is unclear. Methods: We conducted an international prospective, observational, multi-center study in 30 countries in patients undergoing major surgery (> 2-h duration and postoperative intensive care unit (ICU) or high dependency unit admission). The primary endpoint was the occurrence of PO-AKI within 72 h of surgery defined by the Kidney Disease: Improving Global Outcomes (KDIGO) criteria. Secondary endpoints included PO-AKI severity and duration, use of renal replacement therapy (RRT), mortality, and ICU and hospital length of stay. Results: We studied 10,568 patients and 1945 (18.4%) developed PO-AKI (1236 (63.5%) KDIGO stage 1500 (25.7%) KDIGO stage 2209 (10.7%) KDIGO stage 3). In 33.8% PO-AKI was persistent, and 170/1945 (8.7%) of patients with PO-AKI received RRT in the ICU. Patients with PO-AKI had greater ICU (6.3% vs. 0.7%) and hospital (8.6% vs. 1.4%) mortality, and longer ICU (median 2 (Q1-Q3, 1-3) days vs. 3 (Q1-Q3, 1-6) days) and hospital length of stay (median 14 (Q1-Q3, 9-24) days vs. 10 (Q1-Q3, 7-17) days). Risk factors for PO-AKI included older age, comorbidities (hypertension, diabetes, chronic kidney disease), type, duration and urgency of surgery as well as intraoperative vasopressors, and aminoglycosides administration. Conclusion: In a comprehensive multinational study, approximately one in five patients develop PO-AKI after major surgery. Increasing severity of PO-AKI is associated with a progressive increase in adverse outcomes. Our findings indicate that PO-AKI represents a significant burden for health care worldwide

Acute kidney disease beyond day 7 after major surgery: a secondary analysis of the EPIS-AKI trial

Purpose: Acute kidney disease (AKD) is a significant health care burden worldwide. However, little is known about this complication after major surgery. Methods: We conducted an international prospective, observational, multi-center study among patients undergoing major surgery. The primary study endpoint was the incidence of AKD (defined as new onset of estimated glomerular filtration rate (eCFR) < 60 ml/min/1.73 m2 present on day 7 or later) among survivors. Secondary endpoints included the relationship between early postoperative acute kidney injury (AKI) (within 72 h after major surgery) and subsequent AKD, the identification of risk factors for AKD, and the rate of chronic kidney disease (CKD) progression in patients with pre-existing CKD. Results: We studied 9510 patients without pre-existing CKD. Of these, 940 (9.9%) developed AKD after 7 days of whom 34.1% experiencing an episode of early postoperative-AKI. Rates of AKD after 7 days significantly increased with the severity (19.1% Kidney Disease Improving Global Outcomes [KDIGO] 1, 24.5% KDIGO2, 34.3% KDIGO3; P < 0.001) and duration (15.5% transient vs 38.3% persistent AKI; P < 0.001) of early postoperative-AKI. Independent risk factors for AKD included early postoperative-AKI, exposure to perioperative nephrotoxic agents, and postoperative pneumonia. Early postoperative-AKI carried an independent odds ratio for AKD of 2.64 (95% confidence interval [CI] 2.21-3.15). Of 663 patients with pre-existing CKD, 42 (6.3%) had worsening CKD at day 90. In patients with CKD and an episode of early AKI, CKD progression occurred in 11.6%. Conclusion: One in ten major surgery patients developed AKD beyond 7 days after surgery, in most cases without an episode of early postoperative-AKI. However, early postoperative-AKI severity and duration were associated with an increased rate of AKD and early postoperative-AKI was strongly associated with AKD independent of all other potential risk factors