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From ‘goal-directed haemodynamic therapy’ to ‘individualised perioperative haemodynamic management’

2018; Elsevier BV; Volume: 120; Issue: 4 Linguagem: Inglês

10.1016/j.bja.2018.01.001

1471-6771

Daniel A. Reuter, S. Kálmán,

Ultrasound in Clinical Applications

Roughly 20 yr ago, Sinclair and colleagues1Sinclair S. James S. Singer M. Intraoperative intravascular volume optimisation and length of hospital stay after repair of proximal femoral fracture: randomised controlled trial.Br Med J. 1997; 315: 909-912Crossref PubMed Scopus (616) Google Scholar published the first paper on haemodynamic optimisation in surgical patients with the use of oesophageal Doppler ultrasound cardiac output monitoring. Since then, the evidence has become clear that efforts in haemodynamic optimisation can make a great difference for our patients, perhaps not in hospital mortality, but certainly with regard to postoperative complications. Since Sinclair, more than 100 studies have been published, and one could ask, why now another study on this topic? However, we continue to debate a number of relevant questions: What does the term ‘perioperative haemodynamic goal-directed therapy (GDT)’ actually mean? For which patients is this approach really suitable? Is there just one single approach that fits all? Does what we see in randomised controlled trials make a difference in today's clinical practice? Let us start with the easiest part of the term perioperative ‘GDT’; ‘perioperative’. Does it mean to start before surgery with additional more or less invasive haemodynamic monitoring and therapeutic interventions to increase cardiac output, as proposed by some authors?2Cuthbertson B.H. Campbell M.K. Stott S.A. et al.A pragmatic multi-centre randomised controlled trial of fluid loading in high-risk surgical patients undergoing major elective surgery—the FOCCUS study.Crit Care. 2011; 15: R296Crossref PubMed Scopus (10) Google Scholar Or is it sufficient to optimise blood flow after surgery in the ICU?3Gordon A.C. Russell J.A. Goal directed therapy: how long can we wait?.Crit Care. 2005; 9: 647-648Crossref PubMed Scopus (7) Google Scholar At least this first question seems to have been resolved over the last two decades, and it is accepted that optimal timing for such interventions is during and immediately after surgery when the surgical trauma and haemodynamic disturbances occur. However, with GDT becoming one part of multidisciplinary and multimodal treatment approaches such as enhanced recovery after surgery pathways, preoperative fluid management in terms of minimising preoperative fasting is also now being addressed. It is much more difficult to define ‘haemodynamic goals’. As blood flow mainly determines oxygen distribution to end organs, we can agree that GDT is about optimisation of stroke volume and (multiplied by heart rate) of cardiac output. But what is the optimal stroke volume and cardiac output? Is it one magical cut off value for all, as approached in early studies?4Sandham J.D. Hull R.D. Brant R.F. et al.A randomized, controlled trial of the use of pulmonary-artery catheters in high-risk surgical patients.N Engl J Med. 2003; 348: 5-14Crossref PubMed Scopus (1178) Google Scholar Should this goal be within ‘physiological’ ranges, or should it approach ‘supranormal’ values to provide an even larger margin of safety? And what about patient-specific needs—different stages of life, different comorbidities, different forms of surgery, and surgical trauma—will all have different requirements.5Bartha E. Arfwedson C. Imnell A. Kalman S. Towards individualized perioperative, goal-directed haemodynamic algorithms for patients of advanced age: observations during a randomized controlled trial (NCT01141894).Br J Anaesth. 2016; 116: 486-489Abstract Full Text Full Text PDF PubMed Scopus (14) Google Scholar Furthermore, which of the two main therapeutic approaches—fluids or inotropes—should be used initially if this (yet undefined) goal is not reached? The clinical concept of fluid responsiveness has evolved over the last 20 yr, and its use in perioperative GDT strategies has provided many answers in this regard. Giving fluids only makes sense if the patient is fluid responsive,6Meng L Heerdt PM Perioperative goal-directed haemodynamic therapy based on flow parameters: a concept in evolution.Br J Anaesth. 2016; 117: iii3-17Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar an approach that has become a mainstay of nearly all GDT approaches published. Initially, there were many sceptics worried that patients would be volume overloaded by this approach—but experience has shown that in most studies published so far in which fluid responsiveness was used as the trigger for fluid therapy, that the volume of fluids given was less when compared with the control groups.7Michard F. Giglio M.T. Brienza N. Perioperative goal-directed therapy with uncalibrated pulse contour methods: impact on fluid management and postoperative outcome.Br J Anaesth. 2017; 119: 22-30Abstract Full Text Full Text PDF PubMed Scopus (69) Google Scholar However, do positive signs of fluid responsiveness automatically mean that fluids should be given? The political discussion (dominating and frustrating), but in particular the scientific discourse (constructive and instructive), over recent years on crystalloids and colloids, and in particular on the consequences of fluid loading in critically ill patients, led us to question that positive signs of fluid responsiveness should always lead to fluid loading.8Reuter D.A. Chappell D. Perel A. The dark sides of fluid administration in the critically ill.Intensive Care Med. 2017; https://doi.org/10.1007/s00134-017-4989-4Crossref Scopus (26) Google Scholar With the results of the FEDORA trial, Calvo-Veccino and colleagues9Calvo-Vecino J.M. Ripollés-Melchor J. Mythen M.G. et al.Effect of goal-directed haemodynamic therapy on postoperative complications in low–moderate risk surgical patients: a multicentre randomised controlled trial (FEDORA trial).Br J Anaesth. 2018; 120: 734-744Abstract Full Text Full Text PDF PubMed Scopus (85) Google Scholar present in this issue of the British Journal of Anaesthesia another piece in the mosaic of perioperative haemodynamic management. First, we have to keep in mind that this investigation has a couple of important methodological weaknesses, the major one being that the study was prematurely terminated, so it is therefore underpowered. In addition, the outcome measures were changed during the study (to adapt to a change in guidelines for postoperative outcome), and the control group received what is nowadays regarded as very liberal fluid administration. However, it still represents the second biggest study on perioperative haemodynamic GDT to date. Further, in some aspects of data collection, this study was more pragmatic than desired—for example, data on the core intervention of the study, intraoperative haemodynamics, were only sparsely documented, which makes further understanding and interpretation of the results more difficult. Aspects of individualised treatment were also not taken in account—but we have to recognise that the study protocol dates from 2010, when discussions on individualisation were just beginning. In their study, Calvo-Veccino and colleagues9Calvo-Vecino J.M. Ripollés-Melchor J. Mythen M.G. et al.Effect of goal-directed haemodynamic therapy on postoperative complications in low–moderate risk surgical patients: a multicentre randomised controlled trial (FEDORA trial).Br J Anaesth. 2018; 120: 734-744Abstract Full Text Full Text PDF PubMed Scopus (85) Google Scholar enrolled patients who represent the majority of those seen in many surgical services, but who are not currently the focus of GDT: patients with only low to moderate preoperative risk profiles, and undergoing intermediate risk surgery including a large percentage of procedures performed laparoscopically. Given this population, one would expect that the extra effort of GDT would not make any relevant difference. From that perspective, it is even more impressive that GDT could reduce overall complications at 180 days by nearly 50%. So better haemodynamic management seems to make a difference even in these low–moderate risk patients. However, it is still unclear if we need to employ full GDT with advanced haemodynamic monitoring in this group, or if merely a more restricted fluid administration protocol will suffice. Perhaps completely non-invasive advanced monitoring modalities will add value here.6Meng L Heerdt PM Perioperative goal-directed haemodynamic therapy based on flow parameters: a concept in evolution.Br J Anaesth. 2016; 117: iii3-17Abstract Full Text Full Text PDF PubMed Scopus (29) Google Scholar However, it is too soon to stop our efforts in further improving perioperative care. We need to further characterise the pathophysiological mechanisms that influence oxygen delivery during anaesthesia, surgery, and inflammation. And instead of ‘GDT’, we need to further elaborate strategies for ‘individualised perioperative haemodynamic management’, adapted to specific patient groups, risk profiles, and surgical interventions. DAR and SK both developed and wrote this manuscript. D.A.R. has received honoraria from Pulsion Medical Systems and Masimo Corp for consulting. S.K. has no interests to declare.