tion’, implying that most patients ‘should’ receive a particular action. In contrast, level 2 guidelines are essentially ‘suggestions’ and are deemed to be ‘weak’ or discretionary, recognising that management decisions may vary in different clinical contexts. Each recommendation was further graded from A to D by the quality of evidence underpinning them, with grade A referring to a high quality of evidence whilst grade D recognised a ‘very low’ evidence base. The overall strength and quality of the supporting evidence is summarised in table 1 . The guidelines focused on 4 key domains: (1) AKI definition, (2) prevention and treatment of AKI, (3) contrastinduced AKI (CI-AKI) and (4) dialysis interventions for the treatment of AKI. The full summary of clinical practice statements is available at www.kdigo.org, but a few key recommendation statements will be highlighted here.

/pdf/kdigo-clinical-practice-guidelines-for-acute-kidney-injury-27tybolw7l.pdf

KDIGO clinical practice guidelines for acute kidney injury.

We randomly assigned critically ill patients with acute kidney injury and failure of at least one nonrenal organ or sepsis to receive intensive or less intensive renal-replacement therapy. The primary end point was death from any cause by day 60. In both study groups, hemodynamically stable patients underwent intermittent hemodialysis, and hemodynamically unstable patients underwent continuous venovenous hemodiafiltration or sustained low-efficiency dialysis. Patients receiving the intensive treatment strategy underwent intermittent hemodialysis and sustained low-efficiency dialysis six times per week and continuous venovenous hemodiafiltration at 35 ml per kilogram of body weight per hour; for patients receiving the less-intensive treatment strategy, the corresponding treatments were provided thrice weekly and at 20 ml per kilogram per hour. Results Baseline characteristics of the 1124 patients in the two groups were similar. The rate of death from any cause by day 60 was 53.6% with intensive therapy and 51.5% with less-intensive therapy (odds ratio, 1.09; 95% confidence interval, 0.86 to 1.40; P = 0.47). There was no significant difference between the two groups in the duration of renalreplacement therapy or the rate of recovery of kidney function or nonrenal organ failure. Hypotension during intermittent dialysis occurred in more patients randomly assigned to receive intensive therapy, although the frequency of hemodialysis sessions complicated by hypotension was similar in the two groups. Conclusions Intensive renal support in critically ill patients with acute kidney injury did not decrease mortality, improve recovery of kidney function, or reduce the rate of nonrenal organ failure as compared with less-intensive therapy involving a defined dose of intermittent hemodialysis three times per week and continuous renal-replacement therapy at 20 ml per kilogram per hour. (ClinicalTrials.gov number, NCT00076219.)

/pdf/intensity-of-renal-support-in-critically-ill-patients-with-3a2d1ihwlq.pdf

Intensity of renal support in critically ill patients with acute kidney injury

Method and apparatus for utilizing the vascular system as a conduit to reach other vascular and extravascular locations within the body. Included are methods for revascularization wherein the extravascular passageways are formed to permit blood flow between vascular locations. Also included are methods for performing transvascular interstitial surgery (TVIS) wherein extravascular passageways are formed from a blood vessel to another vascular or non-vascular intracorporeal location. Also disclosed are devices usable for forming extravascular passageways in accordance with the invention, or for modifying, valving, maintaining or closing such passageways.

Device, system and method for interstitial transvascular intervention

End-stage renal failure in type 2 diabetes: A medical catastrophe of worldwide dimensions

Our intraaortic cardiac assistance system for patients in cardiogenic shock following myocardial infarction consists of a catheter and balloon inserted through a femoral arteriotomy into the thoracic aorta. The pumping chamber, activated by helium, is synchronized with the heart by signals from the electrocardiogram or the central aortic pressure transducer. Pumping improved two patients' circulatory status; one survived. Two patients died before pumping could begin; in another, an abdominal aortic aneurysm prevented insertion of the pump. Thrombosis did not occur during pumping; hemolysis appeared minimal. Although final evaluation must await more data, balloon pumping appears to be effective in cardiogenic shock. Further study may establish a place for the procedure in myocardial infarction without cardiogenic shock and in low cardiac output syndromes associated with open-heart surgery.

https://jamanetwork.com/journals/jama/articlepdf/337298/jama_203_2_011.pdf

Initial Clinical Experience With Intraaortic Balloon Pumping in Cardiogenic Shock

Diastolic balloon pumping (with carbon dioxide) in the aorta—A mechanical assistance to the failing circulation

We report here our first experience with the use of a total artificial heart in a human being. The heart was developed at the University of Utah, and the patient was a 61-year-old man with chronic congestive heart failure due to primary cardiomyopathy, who also had chronic obstructive pulmonary disease. Except for dysfunction of the prosthetic mitral valve, which required replacement of the left-heart prosthesis on the 13th postoperative day, the artificial heart functioned well for the entire postoperative course of 112 days. The mean blood pressure was 84 +/- 8 mm Hg, and cardiac output was generally maintained at 6.7 +/- 0.8 liters per minute for the right heart and 7.5 +/- 0.8 for the left, resulting in postoperative diuresis and relief of congestive failure. The postoperative course was complicated by recurrent pulmonary insufficiency, several episodes of acute renal failure, episodes of fever of unidentified cause (necessitating multiple courses of antibiotics), hemorrhagic complications of anticoagulation, and one generalized seizure of uncertain cause. On the 92nd postoperative day, the patient had diarrhea and vomiting, leading to aspiration pneumonia and sepsis. Death occurred on the 112th day, preceded by progressive renal failure and refractory hypotension, despite maintenance of cardiac output. Autopsy revealed extensive pseudomembranous colitis, acute tubular necrosis, peritoneal and pleural effusion, centrilobular emphysema, and chronic bronchitis with fibrosis and bronchiectasis. The artificial heart system was intact and uninvolved by thrombosis or infectious processes. This experience should encourage further clinical trials with the artificial heart, but we emphasize that the procedure is still highly experimental. Further experience, development, and discussion will be required before more general application of the device can be recommended.

Clinical use of the total artificial heart.

Excerpt As the youngest volunteer assistant in the Department of Medicine at the University of Gronigen in The Netherlands I had the care of four beds, or rather of the patients that were in them. ...

First Clinical Experience with the Artificial Kidney

Nine patients with renal failure resulting from diabetic nephropathy were treated by hemodialysis. Average duration of diabetes was 21 years, and mean duration of nephropathy was 26 months. One patient survives after more than three years. Others survived for 9, 20, 19, and 13 months, respectively. Overall mortality was 78% at the end of one year. All patients had problems with clotting or infection of bloodstream access routes or both. All had further visual deterioration. Neuropathy was not accelerated. Muscle-wasting, hypoproteinemia, and fluid overload were common. Dialysis for such patients may be considered as a palliative measure with little likelihood of long-term survival or improvement in quality of life.

The sad truth about hemodialysis in diabetic nephropathy.

P O L O N G E D O P E R A T I O N S in the open heart at normal body temperature require heart-lung machines as a substitute for cardiopulmonary function. The principle of all these is the same: they withdraw blood from the venae cavae, oxygenate it, and return it into the aorta. Thus the patient's heart is completely bypassed (Fig. 1). It was believed for a long time that the machine would have to pump and oxygenate blood in amounts equal to the normal resting cardiac output —at least 100 ml. per kg. of body weight per minute. Accordingly, several elaborate machines have been devised to pump and oxygenate 5 liters of blood per minute, for example by Dennis, Jongbloed, and Kol f fand Dubbelman. ' The most successful design was that of Miller, Gibbon, and Gibbon. A similar machine is in use at the Mayo Clinicwith outstanding success; its complexity and cost have prevented its wider use.

https://www.ccjm.org/content/ccjom/23/2/69.full.pdf

Willem J. Kolff

Papers

Diastolic balloon pumping (with carbon dioxide) in the aorta—A mechanical assistance to the failing circulation

Clinical use of the total artificial heart.

First Clinical Experience with the Artificial Kidney

The sad truth about hemodialysis in diabetic nephropathy.

Disposable membrane oxygenator (heart-lung machine) and its use in experimental surgery.