Evaluation of Blood Lactate Level as Predictor of Early Adverse Outcome after Cardiac Surgery under Cardiopulmonary Bypass

Association between lactic acidosis and multiple organ dysfunction syndrome after cardiopulmonary bypass

Background

The relationship between hyperlactatemia and prognosis after cardiopulmonary bypass (CPB) is controversial, and some studies ignore the presence of lactic acidosis in patients with severe hyperlactacemia. This study explored the association between lactic acidosis (LA) and the occurrence of multiple organ dysfunction syndrome (MODS) after cardiopulmonary bypass.

Methods

This study was a post hoc analysis of patients who underwent cardiac surgery between February 2017 and August 2018 and participated in a prospective study at Taizhou Hospital. The data were collected at: ICU admission (H0), and 4, 8, 12, 24, and 48 h after admission. Blood lactate levels gradually increased after CPB, peaking at H8 and then gradually decreasing. The patients were grouped as LA, hyperlactatemia (HL), and normal control (NC) based on blood test results 8 h after ICU admission. Basic preoperative, perioperative, and postoperative conditions were compared between the three groups, as well as postoperative perfusion and oxygen metabolism indexes.

Results

There were 22 (19%), 73 (64%), and 19 (17%) patients in the LA, HL, and NC groups, respectively. APACHE II (24h) and SOFA (24h) scores were the highest in the LA group (P < 0.05). ICU stay duration was the longest for the LA group (48.5 (42.5, 50) h), compared with the HL (27 (22, 48) h) and NC (27 (25, 46) h) groups (P = 0.012). The LA group had the highest incidence of MODS (36%), compared with the HL (14%) and NC (5%) groups (P = 0.015). In the LA group, the oxygen extraction ratio (O2ER) was lower (21.5 (17.05, 32.8)%) than in the HL (31.3 (24.8, 37.6)%) and the NC group (31.3 (29.0, 35.4) %) (P = 0.018). In the univariable analyses, patient age (OR = 1.054, 95% CI [1.003-1.109], P = 0.038), the LA group (vs. the NC group, (OR = 10.286, 95% CI [1.148-92.185], P = 0.037), and ΔPCO2 at H8 (OR = 1.197, 95% CI [1.022-1.401], P = 0.025) were risk factor of MODS after CPB.

Conclusions

We speculated that there was correlation between lactic acidosis and MODS after CPB. In addition, LA should be monitored intensively after CPB.

Role of serum lactate as prognostic marker of mortality among emergency department patients with multiple conditions: A systematic review

Objective

In the Emergency Department, the physician's purpose is to rapidly and accurately diagnose the severity of a patient's condition so that proper treatment can be administered. Therefore, this study pays close attention to the association and prognostic value of blood lactate on different disease outcomes by systematically reviewing recently published studies.

Methods

The search strategy was developed based on searches in the year 2022 for potential publications including original articles, case reports, and reviews using the following web databases google scholar, PubMed, and Science Direct. A total of 25 studies were identified and reviewed extensively to evaluate the link between mortality and serum lactate levels.

Results

This literature review presents the strong association of elevated serum lactate levels with the in-hospital mortality rate among emergency department patients.

Conclusion

These findings suggest that even a moderately raised lactate level in serum can predict the severe outcome in emergency department patients suffering from different conditions. Therefore, early (at the time of administration of hospital) and periodic serum lactate value determination through different techniques and scores is of need and should become part of routine analyses in emergency department to predict and choose therapies that could benefit critically ill patients.

Continuous Lactate Measurement Devices and Implications for Critical Care: A Literature Review

The aim of this article is to review the literature on lactate measurements in critical care and the current devices used to measure noninvasively and invasively. Lactate measurements are currently being used as a way to measure the severity of sepsis. Intravascular and subcutaneous devices are some of the ways that these measurements can be continuously gathered as well as point-of-care blood tests. New devices that are being currently used with athletes can measure lactate noninvasively. As the advance of technology continues to move at a fast speed, an evaluation of literature is needed to assess the continued support of lactate and the ability to move to noninvasive devices in critical care. A literature search was conducted in February 2020, using PubMed, CINAHL, MEDLINE, and Cochrane databases. There remains support for the use of lactate and continuous lactate monitoring; however, currently, noninvasive devices are not available for the critical care environment. There are invasive techniques that are being used to measure lactate continuously in critical care and are beneficial for the cardiac surgery population. The review of the literature on continuous lactate measurements produced evidence that supports prediction of morbidity and mortality. There are no current noninvasive lactate measurement devices that can be used in critical care, but they are being currently used in the athletic community. Invasive continuous lactate measurement devices are currently being used and beneficial.