In July 2015, I wrote that though this topic has never been examined before, "it would be worthwhile to apparoach it in a "critically evaluate lactate monitoring" sort of way". Then, in Question 8 from the first paper of 2016 the college asked the candidates to "critically evaluate the role of monitoring blood lactate levels in the critically ill". It was easy to guess that this was going to come up at some stage. Probably the best published resource for a quick overview of this topic is this review article by Bakker et al (2013).
In the college answer to Question 8 from the first paper of 2016, various statements were made regarding the evidence for lactate monitoring. Below, I have tried to track down the references from where those statements came from.
Jansen, Tim C., Jasper van Bommel, and Jan Bakker. "Blood lactate monitoring in critically ill patients: A systematic health technology assessment*." Critical care medicine 37.10 (2009): 2827-2839.
Okorie, Okorie Nduka, and Phil Dellinger. "Lactate: biomarker and potential therapeutic target." Critical care clinics 27.2 (2011): 299-326.
Mikkelsen, Mark E., et al. "Serum lactate is associated with mortality in severe sepsis independent of organ failure and shock*." Critical care medicine 37.5 (2009): 1670-1677.
Manikis, Panagiotis, et al. "Correlation of serial blood lactate levels to organ failure and mortality after trauma." The American journal of emergency medicine 13.6 (1995): 619-622.
Bernal, William, et al. "Blood lactate as an early predictor of outcome in paracetamol-induced acute liver failure: a cohort study." The Lancet 359.9306 (2002): 558-563.
Jones, Alan E., et al. "Lactate clearance vs central venous oxygen saturation as goals of early sepsis therapy: a randomized clinical trial." Jama 303.8 (2010): 739-746.
Fuller, Brian M., and R. Phillip Dellinger. "Lactate as a hemodynamic marker in the critically ill." Current opinion in critical care 18.3 (2012): 267.
Rivers, Emanuel, et al. "Early goal-directed therapy in the treatment of severe sepsis and septic shock." New England Journal of Medicine 345.19 (2001): 1368-1377.
Donnino, Michael W., et al. "Initial lactate and lactate change in post-cardiac arrest: a multi-center validation study." Critical care medicine 42.8 (2014): 1804.
Craig, Darren George Norman, et al. "Systematic review: prognostic tests of paracetamol‐induced acute liver failure." Alimentary pharmacology & therapeutics 31.10 (2010): 1064-1076.
Bakker, Jan, Maarten WN Nijsten, and Tim C. Jansen. "Clinical use of lactate monitoring in critically ill patients." Annals of intensive care 3.1 (2013): 1.
Shrestha, K. R., B. Pradhan, and B. Koirala. "A prospective randomized study of goal oriented hemodynamic therapy in cardiac surgical patients." Journal of Institute of Medicine (2015).
Pölönen, Pekka, et al. "A prospective, randomized study of goal-oriented hemodynamic therapy in cardiac surgical patients." Anesthesia & Analgesia 90.5 (2000): 1052-1059.
Jansen, Tim C., et al. "Early lactate-guided therapy in intensive care unit patients: a multicenter, open-label, randomized controlled trial." American journal of respiratory and critical care medicine 182.6 (2010): 752-761.