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EDITORIALS: David N Bennett-Jones Early intervention in acute renal failure BMJ 2006; 333: 406-407 [Full text]

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Early intervention in acute renal failure. The importance of assessing fluid status

Jonathan M Gleadle   (25 August 2006)

Evidence of inadequate intravenous fluid therapy in UK hospitals

Nicholas J Matheson, Sarosh R. Irani and Anushka Irani   (31 August 2006)

Early intervention in acute renal failure

Timothy W Evans, Charles Gillbe   (1 September 2006)

Acute renal failure and the need for close collaboration between nephrologists and intensivists

Paul Frost, Matthew Wise, Consultant in Intensive Care Medicine   (3 September 2006)

Early intervention in acute renal failure

Steve R Jones   (3 September 2006)

The Correct Fluid

Duncan L A Wyncoll, Beenu Madhavan   (5 September 2006)

Getting the Fluid into the Patient - practical problems with intravenous fluid managment

Margaret Owen   (11 September 2006)

Early intervention in acute renal failure. The importance of assessing fluid status 25 August 2006
Jonathan M Gleadle, University Lecturer in Nephrology Oxford Kidney Unit, OX3 7LJ Send response to journal: Re: Early intervention in acute renal failure. The importance of assessing fluid status	EDITOR—The article by David Bennett-Jones accurately reviews the management of acute renal failure and the lack of benefit from frusemide1. However, in describing the essential determination of fluid status in such patients the article is deficient and fails to draw upon the admittedly limited evidence base for assessing hypovolaemia2. This is particularly apposite given the preceding editorial by Sharon Strauss highlighting the importance of evidence in diagnostic accuracy3. The editorial by Bennett-Jones suggests ‘Doctors should take a pragmatic and prompt approach to intravenous fluid replacement, based on the patient's blood pressure, capillary refill time, and venous filling’ 1. I would suggest that assessment of fluid status needs to be much broader and incorporate a full history of any fluid gains and losses from the patient, relatives, nurses, fluid balance charts, prescription charts, anaesthetic records and daily weights. The patient should be assessed for symptoms of hypovolaemia which can include postural dizziness, thirst, dry mouth, reduced urine output, feeling cold, shivering, shortness of breath and altered mental status. Furthermore in examining the patient, of central importance are blood pressure, a postural fall in blood pressure, tachycardia (or rarely bradycardia with severe hypovolaemia) and postural changes in pulse rate, whilst capillary refill time is not of proven diagnostic value in adults2. Other signs that should be sought are the level of jugular venous pressure, pallor, peripheral perfusion, the dryness of mucous membranes and the presence of pulmonary and peripheral oedema. If doubt about volume status remains central venous pressure monitoring should be considered. This careful assessment of fluid status is vital prior to the instruction ‘Give intravenous fluids, not loop diuretics’1 to avoid patients developing dangerous pulmonary oedema, particularly since in some studies fluid loading in the intensive care setting has been associated with a higher incidence of acute renal failure4. 1. Bennett-Jones DN Early intervention in acute renal failure. BMJ 2006;333: 406-407 2. McGee S, Abernethy WB, Simel DL. Is this patient hypovolemic? JAMA 1999 281: 1022–1029 3. Bridging the gaps in evidence based diagnosis. Straus SE, BMJ 2006 333: 405-406 4. Van Biesen W, Yegenaga I, Vanholder R, Verbeke F, Hoste E, Colardyn F and Lameire N. Relationship between fluid status and its management on acute renal failure (ARF) in intensive care unit (ICU) patients with sepsis: a prospective analysis. J Nephrol 2005 18:54-60 Competing interests: None declared
Evidence of inadequate intravenous fluid therapy in UK hospitals 31 August 2006
Nicholas J Matheson, SHO in Medicine St Thomas' Hospital, London, SE1 7EH, Sarosh R. Irani and Anushka Irani Send response to journal: Re: Evidence of inadequate intravenous fluid therapy in UK hospitals	In his editorial on early intervention in acute renal failure, David Bennett-Jones emphasises the importance of prompt administration of intravenous fluids [1]. Determination of the appropriate rate of fluid administration must include an estimate of the degree of intravascular volume depletion at the start of therapy, with most aggressive volume expansion targeted at patients with the greatest deficits. To determine whether this simple principle is followed in practice, we audited intravenous fluid prescriptions for 114 consecutive acute surgical admissions to three UK centres (one teaching hospital and two district general hospitals). Elevation of the blood urea:creatinine ratio is commonly used as a quantitative reference standard for the diagnosis of hypovolaemia [2], and similar elevations may be seen in patients with reduced effective intravascular volume secondary to sepsis [3]. We therefore compared the initial rate of intravenous fluid administration for each patient with their urea:creatinine ratio on admission. Patients with chronic renal failure or upper gastrointestinal haemorrhage, or who were taking drugs known to affect this ratio, were excluded from the analysis. Across all admissions, the volume of fluid prescribed over the first hour of treatment ranged from 83 to 1250mls. There was a very low degree of correlation between rate of administration and urea:creatinine ratio, with a correlation coefficient for the complete data set of only 0.23 (95% confidence interval: 0.05 to 0.40). This indicates that just 5.3% of the variation in rate of fluid administration can be explained by an association with urea:creatinine ratio (and hence degree of intravascular volume depletion). The most likely explanation for this finding is a failure by the admitting doctors to appropriately diagnose and treat hypovolaemia. In UK hospitals, fluid prescription is typically left to the most junior members of medical and surgical teams, amongst whom inadequate knowledge is common [4]. There is a clear need for improvement in training and practice in this area, and courses such as ALERT (Acute Life-threatening Events – Recognition and Treatment) may be a good start [5]. The authors would like to thank Nicola Alder, Medical Statistician at the Centre for Statistics in Medicine, Oxford, for her help with data analysis. References: [1] Bennett-Jones DN. Early intervention in acute renal failure. BMJ 2006;333:406-7. [2] McGee S, Abernethy WB, Simel DL. Is This Patient Hypovolaemic? JAMA 1999;281:1022-9. [3] Robinson BE, Weber H. Dehydration Despite Drinking: Beyond the BUN/Creatinine Ratio. J Am Med Dir Assoc 2004;5(2 Suppl):S68-71. [4] Lobo DN, Dube MG, Neal KR, Simpson J, Rowlands BJ, Allison SP. Problems with solutions: drowning in the brine of an inadequate knowledge base. Clinical Nutrition 2001;20(2):125-30. [5] Smith GB, Osgood VM, Crane S, ALERT Course Development Group. ALERT – a multiprofessional training course in the care of the acutely ill adult patient. Resuscitation 2002;52:281-6. Competing interests: None declared
Early intervention in acute renal failure 1 September 2006
Timothy W Evans, Professor of Intensive Care Medicine Royal Brompton Hospital, SW3 6NP, Charles Gillbe Send response to journal: Re: Early intervention in acute renal failure	We read with interest the editorial by Dr. Bennett-Jones (BMJ 2006; 333: 406-407) relating to the use of loop diuretics in acute renal failure (ARF). Whilst we welcome his conclusions relating to clinical practice, we would contest his assertion that prompt initiation of continuous renal replacement therapy is provided by anaesthetists in the intensive care unit. Thus, training in the management of ARF forms part of the competency-based training programme in intensive care medicine (ICM) overseen by the Intercollegiate Board for Training in ICM, established in the early 1990s. ICM achieved specialty recognition throughout the EU in 2000. In the UK, a Diploma in ICM attracted 22 candidates in 2006. Whilst specialist training positions in ICM are open to trainees from anaesthesia, they are also taken up increasingly by those in medical and surgical primary specialties. Whilst intensivists may well be anaesthetists, the reverse is not necessarily true! Charles Gillbe FRCA Chair, Intercollegiate Board for Training in Intensive Care Medicine Timothy Evans FRCP FRCA Chair, Royal College of Physicians of London Critical Care Committee Competing interests: None declared
Acute renal failure and the need for close collaboration between nephrologists and intensivists 3 September 2006
Paul Frost, Consultant in Intensive Care Medicine University Hospital of Wales CF14 4XW, Matthew Wise, Consultant in Intensive Care Medicine Send response to journal: Re: Acute renal failure and the need for close collaboration between nephrologists and intensivists	In his editorial on early intervention in acute renal failure David N Bennett-Jones points out that clinical trials of patients with acute renal failure (ARF) have been difficult because the care of such patients is split between nephrologists and anaethetists [1] This statement implies a detrimental lack of collaboration between these specialists in the management of ARF in the intensive care unit (ICU). This is particularly worrying because it is happening at a time when the epidemiology of ARF is changing, often presenting first to the intensivist in the context of multiple organ failure rather than to the nephrologist as single organ failure [2]. Moreover patients with ARF are increasingly elderly with extensive co-morbidity [3]. Nephrologists and intensivists require a detailed knowledge of an enormous medical literature to optimally manage these patients, this is unlikely to be achieved by either specialist working in isolation of the other. In our opinion the optimal management of ARF in the ICU demands close co-operation between nephrologists and intensivists. Such calls are not new, as long ago as 1998 leading experts were even arguing for a new specialty of critical care nephrology [4]. In the United Kingdom we have a very long way to go before we could even contemplate such a suggestion, as there are no formal links between the professional societies of nephrology and intensive care medicine. Mutual misunderstanding between these specialities can easily arise, even David N Bennett-Jones in this editorial fails to appreciate that not all practitioners of intensive care medicine are anaethetists. Specialty training represents an obvious route to improve this situation but unfortunately despite the fact that some 25% of all admissions to the ICU develop ARF [5] there is no compulsion on nephrology or intensive care medicine trainees to complete SpR posts in the other specialty. It should be remembered that patients with ARF are at high risk of death [6] and in our opinion such patients deserve close collaboration between the specialties that are most able to help them [1]. Bennett-Jones DN. Early intervention in acute renal failure. BMJ 2006;332:406-7 [2]. Liano F, Junco E, Pascual J, Madero R, Verde E and the Madrid Acute Renal Failure Study Group. The spectrum of acute renal failure in the intensive care unit compared with that seen in other settings. Kidney Int 1998; 53: S16-S24 [3]. Metcalfe W, Simpson M, Kahn IH, Prescott GJ, Simpson K, Smith WCS et al. Acute renal failure requiring renal replacement therapy: incidence and outcome. Q J Med 2002; 95: 579-583 [4]. Ronco C, Bellomo R, Feriani M, LaGreca G. Critical care nephrology: The time has come. Kidney Int 1998; 53: S1-S2 [5]. de Mendonca A, Vincent JL, Suter PM, Moreno R, Dearden NM, Antonelli M et al. Acute renal failure in the ICU; Risk factors and outcome evaluated by the SOFA score. Intensive Care Med 2000; 26:915-21 [6]. Bagshaw SM, Laupland KB, Doig CJ, Mortis G, Fick GH, Mucenski M et al. prognosis for long term survival and renal recovery in critically ill patients with severe acute renal failure: A population based study. Crit Care 2005; 9:700-9 Competing interests: None declared
Early intervention in acute renal failure 3 September 2006
Steve R Jones, Specialist Registrar in Emergency and Intensive Care Medicine Manchester Royal Infirmary, Oxford Road, Manchester, M13 9WL Send response to journal: Re: Early intervention in acute renal failure	I read with interest the editorial by Dr. Bennett-Jones relating to the use of loop diuretics in acute renal failure (BMJ 2006; 333: 406-407). I also read with interest the Rapid Response by Gillbe and Evans. Unfortunately, despite my initial intention to post a rapid response along similar lines, I left it "under the blotter" too long and have only posted now. Our points, however, are similar: intensivists may well be anaesthetists but not necessarily so. All three of central Manchester’s intensive care units have non-anaesthetic consultant staff and this represents an increasing trend locally and nationally. This point may seem superficial but for patients and relatives at their most vulnerable clarity remains important. Steve Jones MD MRCP FRCSEd FCEM Competing interests: None declared
The Correct Fluid 5 September 2006
Duncan L A Wyncoll, Consultant in Intensive Care Guy's & St Thomas' Hospital, Lambeth Palace Road, Lonon, SE1 7EH, Beenu Madhavan Send response to journal: Re: The Correct Fluid	EDITOR - We read with interest the editorial by Dr. Bennett-Jones that highlighted the importance of a prompt approach to treating hypovolaemia with intravenous fluids as the only reliable means of renal protection1. However, there was no comment on the composition of the fluid. This may be very important, particularly in clinical situations where large volumes of fluid are administered during resuscitation, and may well affect the degree of renal protection and subsequent outcome. The commonest fluid chosen for resuscitation is often 0.9% sodium chloride, often called normal saline (NS), which frequently causes hyperchloraemic metabolic acidosis (HCMA)2. Although some clinicians argue that HCMA does not cause direct harm, it may result in the incorrect treatment of the acidosis. Unfortunately, there are relatively few clinical studies comparing NS with balanced electrolyte solutions (such as Hartmann’s solution or Ringer’s lactate), yet although they are small, they nearly all suggest that NS is not the optimal fluid for the majority of patients. It has been known for many years that hyperchloraemia causes renal artery vasoconstriction and a progressive fall in glomerular filtration rate3. In a comparison of NS with a balanced electrolyte solution in human volunteers, NS was associated with significantly more abdominal discomfort and a slower time to urination4. In a recent study of patients undergoing renal transplantation who were randomised to NS or lactated Ringer’s solution, those who received NS had significantly more hyperkalaemia and acidosis5. Increasing awareness of the ‘Stewart hypothesis’ has led to new ways of managing acid-base balance. We would argue that it is preferable to avoid the iatrogenic problem of saline-induced HCMA and its associated morbidity, and choose a balanced electrolyte solution for basic initial fluid resuscitation. 1. Bennett-Jones DN. Early intervention in acute renal failure. BMJ 2006;333:406- 407. 2. Kellum JA. Saline-induced hyperchloremic metabolic acidosis. Crit Care Med 2002;31:259–261. 3. Wilcox CS. Regulation of renal blood flow by plasma Chloride. J Clin Invest 1983;71:726-735. 4. Williams EL, Hildebrand KL, McCormick SA, Bedel MJ. The effect of intravenous lactated Ringer's solution versus 0.9% sodium chloride solution on serum osmolality in human volunteers. Anesth Analg 1999;88:999 -1003. 5. O’Malley CM, Frumento RJ, Hardy MA, Benvenisty TE, Mercer JS, Bennett-Guerrero E. A randomised, double blind comparison of lactated ringers solution and 0.9% NaCl during renal transplantation. Anesth Analg 2005;100:1515–1524. Competing interests: None declared
Getting the Fluid into the Patient - practical problems with intravenous fluid managment 11 September 2006
Margaret Owen, Specialist Registrar Anaesthetics Western Infirmary, Dumbarton Road, Glasgow G11 6NT Send response to journal: Re: Getting the Fluid into the Patient - practical problems with intravenous fluid managment	EDITOR – Matheson (Evidence of inadequate fluid treatment in UK hospitals - BMJ letters 9th September 2006) highlights a problem of inadequate fluid prescription in surgical patients.(1) In an audit of preoperative fluid management of hip fracture patients at Royal Alexandra Hospital, Paisley, in 2004 we found hypovolaemia to be similarly under- treated, but rather than inadequate prescription, we found inadequacy in the administration of fluids. 54 consecutive patients were studied: their notes were examined for fluid prescription and these were compared with fluid balance charts to see what fluid each patient actually received from admission up until entry to the anaesthetic room. Patients were written up for on average 111 ml/hr of crystalloid (range of 83-500 ml/hr) but the average rate of fluid actually administered during preoperative fasting was only 53 mls/hr (range of 0-107 ml/hr). In all cases patients received less fluid than they were prescribed, over half received less than half what they were prescribed, and 3 out of the 54 patients did not receive any intravenous fluid at all. Following delays or interruptions to fluid infusions there was no evidence that rate of subsequent fluid administration was ever increased to compensate for the short-fall, and thus the tendency was always for patients to fall behind with their fluids. Good fluid management, which should be fairly straightforward, turns out to be a complicated business. As well as getting the initial prescription for fluid replacement right, junior doctors must ensure adequate, well-positioned intravenous access and be prepared to return when necessary if problems arise with cannulas. Managing intravenous infusions is demanding of nursing time too, especially if infusion pumps are not available for all patients. The particular problem highlighted by our audit was that no member of staff, nursing or medical, appeared to take responsibility for updating fluid prescriptions after delays or interruptions in infusions. The benefits of adequate fluid resuscitation in this group of patients have been well documented(2), but we still don’t seem to be getting it right. The practicalities of managing intravenous infusions require a high degree of inter-professional communication and co- operation. Perhaps a more flexible approach to prescribing fluids that would allow nurses to increase flow rates where appropriate would help. Other practical ideas might include improving cannulation skills among medical staff and training more nurses to cannulate. Certainly, more infusions pumps would help. And perhaps a dispelling of the myth, common among medical and nursing staff alike, that intravenous fluid (like high flow oxygen) is highly dangerous for frail and elderly patients and to be used sparingly at all times. Although cases of fluid overload do occasionally occur, it is far more common to find dehydration in this group of patients(3) with the attendant complications of intra-operative cardiovascular instability and post-operative renal failure. References: (1) Matheson NJ, Irani SR, Irani A Evidence of inadequate fluid treatment in UK hospitals BMJ 2006; 333: 551 (9th September) (2) Venn R, Steele A, Richardson P, Poloniecki J, Grounds M, Newman P. Randomized controlled trial to investigate influence of the fluid challenge on duration of hospital stay and perioperative morbidity in patients with hip fractures. British Journal of Anaesthesia 2002; 88: 65–71. (3) A study of the initial fluid resuscitation and pain management of patients with fractured , neck of femur [Abstracts: Abstracts from the Age Anaesthesia Association Annual Meeting in Grange over Sands, Cumbria, on 10 May 2002] Levy, N. Competing interests: None declared