No abstract

Cardiac surgery-associated acute kidney injury (CS-AKI) is a major complication associated with increased morbidity and mortality. There are multiple diagnostic criteria for CS-AKI. Despite many new investigations available for improved AKI diagnostics, creatinine and urea remain the cornerstone of diagnostics in everyday clinical practice. There are three major pathophysiological mechanisms that contribute to kidney injury, i.e. renal hypoperfusion, inflammation with oxidative stress, and use of nephrotoxic agents. Some risk factors have been identified that can be modified during the course of treatment (use of nephrotoxic agents, duration of cardiopulmonary bypass, type of extracorporeal circulation, postoperative low cardiac output or hypotension). The aim of AKI prevention should always be to prevent aggravation of renal failure and, if possible, to avoid progression to renal replacement therapy, which in turn brings worse long-term outcomes.

Background Pocket-related complications following the implantation of cardiovascular implantable electronic devices primarily include pocket hematoma, infection, skin erosion or decubitus, device migration, and Twiddler's syndrome, with other pathologies such as nerve impairment or bone lesions being extremely rarely encountered. We report a case of a 20-year old asthenic, non-athlete female patient presenting with a device-generated fracture of the second rib several months after sub-muscular permanent pacemaker implantation due to repeated bilateral pre-pectoral pocket infections. Case presentation A 20-year old female patient was readmitted to our institution 9 months following sub-pectoral implantation of a permanent pacemaker, complaining of severe pocket-related pain, which arose spontaneously in the absence of direct trauma, intense physical activity or vigorous coughing, and was associated with normal day-to-day activity. To rule out a pacemaker re-infection, a native computed tomography and a positron emission tomography—computed tomography of the thorax were performed. Both modalities excluded an infection but showed a healing fracture and a focus of enhanced metabolic activity in the anterolateral part of the right second rib, indicating a non-traumatic or stress fracture of the bone. Consequently, a complete extraction of the pulse generator and both leads was performed and the smallest available single-chamber pulse generator with a single atrial electrode was implanted in the sub-fascial, pre-muscular pocket in the now recovered and uninfected left subclavicular region, alleviating patient’s severe pain symptoms and significantly enhancing her quality of life. Conclusions In the absence of direct trauma, intense physical activity or vigorous coughing, we assume that in this asthenic girl a normal day-to-day motion of the right shoulder has persistently forced the sub-muscularly placed pulse generator toward thoracic wall, putting increased repetitive pressure force on the underlying bones, finally causing a fatigue stress fracture of the second rib. In asthenic phenotype patients with small thorax and short subclavicular distance, a sub-muscular pacemaker implantation can potentially cause unique and unexpected pocket-related adverse events necessitating advanced diagnostics and timely treatment.

Objectives Acute kidney injury (AKI) is associated with higher perioperative mortality and morbidity. Oxidative stress has been proposed as a cause of postoperative AKI. Ascorbic acid (AA) supplementation was suggested as a novel and promising antioxidant. The aim of this study was to evaluate the capability of AA to reduce the incidence of postoperative AKI in cardiac surgery patients. Methods A prospective randomized trial was conducted in patients scheduled for on-pump cardiac surgery. Subjects in the AA group received 2 g of AA intravenously during the induction of anesthesia, 2 g before aortic cross-clamp removal and 1 g every 8 hours for five postoperative days (the JERICA protocol). Postoperatively, the patients were monitored for AKI and other complications. Malondialdehyde levels were monitored in a subpopulation of 100 patients to evaluate the effect of AA on oxidative stress level. Results The AA and control group consisted of 163 and 169 patients, respectively. The groups were well matched for baseline demographics and had similar intraoperative characteristics. The incidence of AKI in the AA and control group was 20.9 and 28.4%, respectively (p = 0.127). The estimated glomerular filtration rate did not differ between the study groups in the entire postoperative period. There was a trend toward higher malondialdehyde values with statistical significance on postoperative day 1 and lower in-hospital mortality in the AA group (0.6 vs. 4.1%, p = 0.067). Conclusion Our results do not support the effectiveness of AA supplementation in reducing the incidence of postoperative AKI in on-pump cardiac surgery patients. Clinical Registration Number This study was registered with the ISRCTN Registry under the trial registration number ISRCTN98572043.