In the last 50 years the anesthesia related mortality decreased dramatically and actually is a rare event(1). In contrast, in Europe, the in-hospital mortality after non cardiac surgery Is 4%(2). The relationship between intraoperative arterial blood pressure and serious complications is of critical importance in perioperative medicine. Hypertension and hypotension can impair function of vital organs such as brain, heart and kidneys.

Several studies have demonstrated associations between low mean arterial pressure (MAP), organ injury, as well as, 30-day mortality(3–9). Blood pressure (BP) has become one of the most important vital signs evaluated in the perioperative setting.

Recently the SIAARTI recommends, with a low level of evidence, to continuously monitor the blood pressure (CNBP) during the intraoperative period. Although BP is mandatorily and regularly monitored in perioperative care, a consensus on explicit BP targets for different surgical patient populations is still lacking. Different patients and surgeries involve different concerns during the determination of BP targets: systolic, mean, diastolic, absolute values, relative change from baseline, various threshold, area under the threshold, average, time-weighted average, minimum, duration of the minimum, etc.

In recent years there has been a trend to maintain MAP higher than 65 mmHg to avoid adverse outcomes(4). Some studies show improvement in postoperative outcomes when an individualized blood pressure management strategy is used during surgery that is tailored to the individual patient (reduction from preoperative value)(10). Indeed, it is argued that associations based on relative MAP are not stronger than those based on absolute thresholds (intraoperative MAP)(3). Also, not only the depth of hypotension but also the cumulative time spent in hypotension can be associated with worse outcomes(4,11).

Intraoperative blood pressure is usually measured intermittently using noninvasive oscillometric devices every 3–5 minutes; with this monitoring strategy short detrimental periods of hypotension can be ignored leading to changes in vital organ’s perfusion(12). Continuous monitoring facilitates early diagnoses of hypotension, this could potentially promote a timely treatment. Commonly, invasive blood pressure monitoring, which provides continuous blood pressure, is used in selected high-risk patients. As an alternative, continuous non-invasive blood pressure (CNBP) monitoring with finger-cuff method may be of potential benefit. This device uses the volume- clamp(13,14) method and the physiocal algorithm for continuous BP estimation (ClearSight® Edwards Lifesciences Corp, Irvine, CA), using a cuff placed around the finger’s middle phalange. Arterial pressures measured from this monitor are comparable to invasive blood pressure monitoring(15–17), and noninferior to conventional automatic oscillometric methods(18).

Continuous non-invasive arterial pressure monitoring has the potential to decrease the duration of intraoperative hypotension and hypertension compared to conventional intermittent blood pressure monitoring. Chen et al. demonstrated using continuous non-invasive arterial pressure devices for every hour of surgery it is possible to identify an average of 14 minutes of potentially treatable hypotensive and hypertensive time(12). Whether the ability to detect more hypotension events by continuous non-invasive arterial pressure monitoring use can improve patient outcomes, is still an open research question.

Background

1. Li G, Warner M, Lang BH, Huang L, Sun LS. Epidemiology of Anesthesia-related Mortality in the United States, 1999–2005. Anesthesiology. 2009 Apr 1;110(4):759–65.

2. Pearse RM, Moreno RP, Bauer P, Pelosi P, Metnitz P, Spies C, et al. Mortality after surgery in Europe: a 7 day cohort study. The Lancet. 2012 Sep;380(9847):1059–65.

3. Salmasi V, Maheshwari K, Yang D, Mascha EJ, Singh A, Sessler DI, et al. Relationship between Intraoperative Hypotension, Defined by Either Reduction from Baseline or Absolute Thresholds, and Acute Kidney and Myocardial Injury after Noncardiac Surgery. Anesthesiology. 2017 Jan 1;126(1):47–65.

4. Walsh M, Devereaux PJ, Garg AX, Kurz A, Turan A, Rodseth RN, et al. Relationship between Intraoperative Mean Arterial Pressure and Clinical Outcomes after Noncardiac Surgery. Anesthesiology. 2013 Sep 1;119(3):507–15.

5. Abbott TEF, Pearse RM, Archbold RA, Ahmad T, Niebrzegowska E, Wragg A, et al. A Prospective International Multicentre Cohort Study of Intraoperative Heart Rate and Systolic Blood Pressure and Myocardial Injury After Noncardiac Surgery. Anesthesia & Analgesia. 2018 Jun;126(6):1936–45.

6. Sun LY, Wijeysundera DN, Tait GA, Beattie WS. Association of Intraoperative Hypotension with Acute Kidney Injury after Elective Noncardiac Surgery. Anesthesiology. 2015 Sep 1;123(3):515–23.

7. van Waes JAR, van Klei WA, Wijeysundera DN, van Wolfswinkel L, Lindsay TF, Beattie WS. Association between Intraoperative Hypotension and Myocardial Injury after Vascular Surgery. Anesthesiology. 2016 Jan 1;124(1):35–44.

8. Sessler DI, Meyhoff CS, Zimmerman NM, Mao G, Leslie K, Vásquez SM, et al. Period-dependent Associations between Hypotension during and for Four Days after Noncardiac Surgery and a Composite of Myocardial Infarction and Death. Anesthesiology. 2018 Feb 1;128(2):317–27.

9. Ahuja S, Mascha EJ, Yang D, Maheshwari K, Cohen B, Khanna AK, et al. Associations of Intraoperative Radial Arterial Systolic, Diastolic, Mean, and Pulse Pressures with Myocardial and Acute Kidney Injury after Noncardiac Surgery. Anesthesiology. 2020 Feb 1;132(2):291–306.

10. Futier E, Lefrant J-Y, Guinot P-G, Godet T, Lorne E, Cuvillon P, et al. Effect of Individualized vs Standard Blood Pressure Management Strategies on Postoperative Organ Dysfunction Among High-Risk Patients Undergoing Major Surgery. JAMA. 2017 Oct 10;318(14):1346.

11. Bijker JB, Persoon S, Peelen LM, Moons KGM, Kalkman CJ, Kappelle LJ, et al. Intraoperative Hypotension and Perioperative Ischemic Stroke after General Surgery. Anesthesiology. 2012 Mar 1;116(3):658–64.

12. Chen G, Chung E, Meng L, Alexander B, Vu T, Rinehart J, et al. Impact of non invasive and beat-to-beat arterial pressure monitoring on intraoperative hemodynamic management. Journal of Clinical Monitoring and Computing. 2012 Apr 1;26(2):133–40.

13. Penaz. Photoelectric Measurement of blood pressure, volume and flow in the finger. Digest of the 10th international conference on medical and biological engineering. 1973;

14. Wesseling KH, W de, B, H van der, GMA, G van, J, & SJJ. Physiocal, calibrating finger vascular physiology for finapres. Homeostasis. 1995;36(2):67–82.

15. Martina JR, Westerhof BE, van Goudoever J, de Beaumont EMFH, Truijen J, Kim Y-S, et al. Noninvasive Continuous Arterial Blood Pressure Monitoring with Nexfin®. Anesthesiology. 2012 May 1;116(5):1092–103.

16. Ilies C, Grudev G, Hedderich J, Renner J, Steinfath M, Bein B, et al. Comparison of a continuous noninvasive arterial pressure device with invasive measurements in cardiovascular postsurgical intensive care patients. European Journal of Anaesthesiology. 2015 Jan;32(1):20–8.

17. Noto A, Sanfilippo F, de Salvo G, Crimi C, Benedetto F, Watson X, et al. Noninvasive continuous arterial pressure monitoring with Clearsight during awake carotid endarterectomy. European Journal of Anaesthesiology. 2019 Feb;36(2):144–52.

18. Eeftinck Schattenkerk DW, van Lieshout JJ, van den Meiracker AH, Wesseling KR, Blanc S, Wieling W, et al. Nexfin Noninvasive Continuous Blood Pressure Validated Against Riva-Rocci/Korotkoff. American Journal of Hypertension. 2009 Apr;22(4):378–83.

19. Devereaux PJ, Chan MT, Alonso-Coello P, Walsh M BO, Villar JC, Wang CY, et al. Association Between Postoperative Troponin Levels and 30-Day Mortality Among Patients Undergoing Noncardiac Surgery. JAMA. 2012 Jun 6;307(21):2295.

References