DRENZLA on FLUIDS
Adam Drenzla, a bright and inquisitive ICU registrar, recently sent in these insightful comments, having been inspired by an excellent podcast on EMCRIT and a powerful post by Cliff Reid both about “chloride poisoning” and intravenous fluids.
Adam, Scott Weingart and Cliff Reid will all be at the upcoming SMACC conference.
Adam writes:
The Austin group should be praised for raising our awareness of the dangers of overzealous chloride administration (1,2,3) but it’s also wise to consider the safety of alternative anions.
Little work it seems has been done on the safety of IV gluconate infusion, whilst acetate has been documented to have extensive adverse physiological effects to the point of its abandonment in RRT fluids (see, for example, the discussion of reference 4).
Lactate also seems to deserve more attention. First there is the issue of racemic mixtures and whether they have clinical consequences different to those of l-lactate alone. Second, lactate is far from being a metabolic waste product – it’s elevation in shock states may be a beneficial adaptation to energetic crisis by providing an efficient, abundant fuel for many cells including the myocardium (5,6).
To my mind, any head-to-head comparison of IV fluid therapy should keep in mind these potential benefits.
Lastly, whenever studies appear that support our clinical prejudices we do feel happy to receive “confirmation” however we should not forget to continue in our attempts at falsification and indeed this should feel just as gratifying. Neil Soni and coworkers have written two papers on balanced fluids from a vantage point which slows the band wagon (7,8). Such an approach is necessary in evaluating the place of any new research which should be the job of editorialists and reviewers – well done by JAMA (9), not so by Annals of Surgery (10, 11).
Without going into the nitty-gritty of the two recent papers from which this discussion springs, no agnostic would find them practice changing. They are still important however in reminding us, as Waikar and Winkelmayer emphasize, that “IV fluids bypass many of our bodies most important defences and reach into our deepest intracellular and interstitial recesses”.
IV Fluids should be, at the very least, safe and thoroughly evaluated.
1.Yunos, et al. Bench-to-bedside review: Chloride in critical illness. Crit Care 2010, 14(4), 226-236 http://www.ncbi.nlm.nih.gov/pubmed/20663180
2. Yunos, et al. The biochemical effects of restricting chloride-rich fluids in intensive care. Crit Care Med. 2011, 39(11) 2419-2424 http://www.ncbi.nlm.nih.gov/pubmed/21705897
3. Yunos et al. Association between a chloride-liberal vs chloride-restrictive intravenous fluid administration strategy and kidney injury in critically ill adults. JAMA, 2012, 308(15), 1566-1572 http://www.ncbi.nlm.nih.gov/pubmed/23073953
4. Davies et al. Plasma acetate, gluconate and interleukin-6 profiles during and after cardiopulmonary bypass: a comparison of Plasma-lyte 148 with a bicarbonate balanced solution. Crit Care 2011, 15(1), R21 http://www.ncbi.nlm.nih.gov/pubmed/21235742
5. Matejovic et al. Lactate in shock: a high-octane fuel for the heart? Intensive Care Med, 2007, 33(3), 406-408 http://www.ncbi.nlm.nih.gov/pubmed/17242932
6. Wagner et al. Hypertonic lactate solutions: a new horizon for fluid resuscitation? Intensive Care Med, 2008, 34(10), 1749-1751 http://www.ncbi.nlm.nih.gov/pubmed/18563388
7. Guidet et al. A balanced view of balanced solutions. Crit Care 2010, 14(5), 325 http://www.ncbi.nlm.nih.gov/pubmed/21067552
8.Handy, Soni. Physiological effects of hyperchloremia and acidosis. BJA 2008, 101(2), 141-150 http://www.ncbi.nlm.nih.gov/pubmed/18534973
9. Waikar, Winkelmayer. Saving the kidneys by sparing intravenous chloride? JAMA, 308(15), 1583-1585 http://www.ncbi.nlm.nih.gov/pubmed/23073956
10. Shaw et al. Major complications, mortality, and resource utilization after open abdominal surgery: 0.9% saline compared to Plasma-lyte. Ann Surgery 2012, 255(5), 821-29 http://www.ncbi.nlm.nih.gov/pubmed/22470070
11. Lobo. Intravenous 0.9% saline and general surgical patients: a problem, not a solution Ann Surg 2012, 255(5), 830-832 http://www.ncbi.nlm.nih.gov/
Phot credit (creative commons) here