Sympathetic stimulation increases serum lactate concentrations in patients admitted with sepsis: implications for resuscitation strategies

High Respiratory and Cardiac Drive Exacerbate Secondary Lung Injury in Patients With Critical Illness

The high respiratory and cardiac drive is essential to the host-organ unregulated response. When a primary disease and an unregulated secondary response are uncontrolled, the patient may present in a high respiratory and cardiac drive state. High respiratory drive can cause damage to the lungs, pulmonary circulation, and diaphragm, while high cardiac drive can lead to fluid leakage and infiltration as well as pulmonary interstitial edema. A "respiratory and cardiac dual high drive" state may be a sign of an unregulated response and can lead to secondary lung injury through the increase of transvascular pressure and pulmonary microcirculation injury. Ultrasound examination of the lung, heart, and diaphragm is important when evaluating the phenotype of high respiratory drive in critically ill patients. Ultrasound assessment can guide sedation, analgesia, and antistress treatment and reduce the risk of high respiratory and cardiac drive-induced lung injury in these patients.

Changes of serum NSE, lactate and CRP in patients with postoperative infection after acute craniocerebral injury and their predictive value for prognosis

To investigate the changes of serum neuron-specific enolase (NSE), lactate and C-reactive protein (CRP) in patients with postoperative infection after acute craniocerebral injury and their predictive value for prognosis. 71 patients with postoperative infection after acute craniocerebral injury were selected as infection group, and 56 patients without postoperative infection were selected as non-infection group. NSE, CRP and blood lactic acid levels were detected in all patients. The relationship between each index and thecondition and prognosis of patients was analyzed. The levels of serum NSE, lactic acid and CRP in infected group were higher than those in non-infection group (P<0.05). The levels of serum NSE, lactic acid and CRP in severe group were higher than those in mild group (P<0.05). Serum levels of NSE, lactic acid and CRP were positively correlated with the severity of infection (P<0.05), the area under the curve (AUC) of the receiver operating characteristic curve (ROC) was greater than that of the NSE level (P<0.05). The levels of serum NSE, lactate and CRP in the good prognosis group were lower than those in the poor prognosis group (P<0.05). The area under the curve (AUC) of receiver operating characteristic curve (ROC) of lactate level in predicting the prognosis of patients with infection was higher than that of NSE and CRP (P<0.05). Serum NSE, lactic acid and CRP have predictive value in patients with acute craniocerebral injury.

Association Between Lactate and 28-Day Mortality in Elderly Patients with Sepsis: Results from MIMIC-IV Database

INTRODUCTION

This study aimed to explore the association of serum lactate with clinical outcomes in elderly patients with sepsis based on data from the MIMIC-IV database.

METHODS

All elderly patients with sepsis (age ≥ 65 years) were included. Different models were constructed for exploring the relationships between lactate and 28-day mortality. A two-segment linear regression model was performed to verify the threshold effects of lactate on clinical outcomes and smooth curve fitting was performed.

RESULTS

A total of 4199 elderly patients with sepsis were included. The 28-day mortality was 32.22% (n = 1395). After adjustment for all potential cofounders, for each 1 mmol/l increment in lactate, the odds ratio (OR) of 28-day mortality was 1.23 (95% CI 1.18-1.28, P < 0.0001). Smooth fitting curves indicated a non-linear positive relationship between lactate and 28-day mortality. The turning point of lactate level was 5.7 mmol/l: at ≤ 5.7 mmol/l, with each 1 mmol/l increment in lactate, the risk of 28-day mortality increased significantly (OR 1.32, 95% CI 1.25-1.38, P < 0.0001); the significantly positive relationship was still present at lactate > 5.7 mmol/l (OR 1.10, 95% CI 1.04-1.18, P = 0.0019). The area under the ROC curve (AUC) of lactate was 0.618 (95% CI 0.599-0.635) and the cutoff value of lactate was 2.4 mmol/l with a sensitivity of 0.483 and a specificity of 0.687.

CONCLUSION

In elderly patients with sepsis, a non-linear positive relationship was discovered between serum lactate and 28-day mortality. Physicians should be alert to lactate assessment at admission and pay more attention to those patients with higher levels of lactate.

The predictive value of serum lactate to forecast injury severity in trauma-patients increases taking age into account

BACKGROUND

Two-tier trauma team activation (TTA)-protocols often fail to safely identify severely injured patients. A possible amendment to existing triage scores could be the measurement of serum lactate. The aim of this study was to determine the ability of the combination of serum lactate and age to predict severe injuries (ISS > 15).

METHODS

We conducted a retrospective cohort study in a single level one trauma center in a 20 months study-period and analyzed every trauma team activation (TTA) due to the mechanism of injury (MOI). Primary endpoint was the correlation between serum lactate (and age) and ISS and mortality. The validity of lactate (LAC) and lactate contingent on age (LAC + AGE) were assessed using the area under the curve (AUC) of the receiver operating characteristics (ROC) curve. We used a logistic regression model to predict the probability of an ISS > 15.

RESULTS

During the study period we included 325 patients, 75 met exclusion criteria. Mean age was 43 years (Min.: 11, Max.: 90, SD: 18.7) with a mean ISS of 8.4 (SD: 8.99). LAC showed a sensitivity of 0.82 with a specificity of 0.62 with an optimal cutoff at 1.72 mmol/l to predict an ISS > 15. The AUC of the ROC for LAC was 0.764 (95% CI: 0.67-0.85). The LAC + AGE model provided a significantly improved predictive value compared to LAC (0.765 vs. 0.828, p < 0.001).

CONCLUSIONS

The serum lactate concentration is able to predict injury severity. The prognostic value improves significantly taking the patients age into consideration. The combination of serum lactate and age could be a suitable Ad-on to existing two-tier triage protocols to minimize undertriage.

LEVEL OF EVIDENCE

Level IV, retrospective cohort study.

Normal Saline Solution or Lactated Ringer's Solution to Enhance Lactate Clearance in Septic Patients After Initial Resuscitation in the ED: A Retrospective Cohort Trial

Objective

To compare the effect of isotonic crystalloid solutions between lactated Ringer’s solution (LRS) and normal saline solution (NSS) on lactate clearance in septic patients at the emergency department (ED).

Materials and Methods

This study is a single-center retrospective chart review. The study enrolled patients older than 18 years with sepsis and initial serum lactate level >2 mg/dL in the ED. The primary outcome was to determine which isotonic solution was better for serum lactate clearance in septic patients. The secondary outcomes were serum creatinine change within 24 h and the 48-h survival rate after admission.

Results

A total of 120 patients were enrolled with a median crystalloid volume administered in the ED of 1000 mL. Within 2 h of resuscitation, there was no difference in lactate clearance between the LRS and NSS groups with median values of 29.2% and 25%, respectively (P=0.839). The 48-h survival rate after admission did not differ between the LRS and NSS groups with median values of 90% and 86%, respectively. Both isotonic solutions increased serum creatinine levels within 24 h of treatment with median values of 0.3 for each group (P=0.647).

Conclusion

Among septic patients in the ED treated with NSS or LRS, there was no difference in lactate clearance, serum creatinine change within 24 h, or 48-h survival. However, several factors were associated with increased lactate levels, such as older age and use of vasopressors and immunosuppressive agents.

Elevated serum lactate levels and age are associated with an increased risk for severe injury in trauma team activation due to trauma mechanism

BACKGROUND

The identification of risk factors for severe injury is crucial in trauma triage and trauma team activation (TTA) depends on a sufficient triage. The aim of this study was to determine whether or not elevated serum lactate levels and age are risk factors for severe injury in TTA due to trauma mechanism.

METHODS

We conducted a retrospective cohort study in a single level one trauma center between September 2019 and May 2021 and analysed every TTA due to trauma mechanism. Primary endpoint of interest was the association of serum lactate as well as age with injury severity assessed by the injury severity score (ISS).

RESULTS

During the study period, we included 250 patients. Mean age was 43.3 years (Min.: 11, Max.: 90, SD: 18.7) and the initial lactate level was 1.7 mmol/L (SD: 0.95) with a mean ISS of 8.4 (SD: 8.99). The adjusted odds ratio (OR) for age > 65 being associated with an ISS > 16 is 9.7 (p < 0.001; 95% CI 4.01-25.58) and for lactate > 2.2 mmol/L being associated with an ISS > 16 is 6.29 (p < 0.001; 95% CI 2.93-13.48). A lactate level of > 4 mmol/L results in a 36-fold higher risk of severe injury with an ISS > 16 (OR 36.06; 95% CI 4-324.29).

CONCLUSION

This study identifies age (> 65) and lactate (> 2.2 mmol/L) as independent risk factors for severe injury in a TTA due to trauma mechanism. Existing triage protocols might benefit from congruous amendments.