Assessment of Tissue Perfusion Using the Peripheral Perfusion Index and Lactate Clearance in Shock in Pediatric Patients

Unraveling the role of lactate-related genes in myocardial infarction

Background

Lactate is a crucial intermediary, facilitating communication between myocardial energy metabolism and microenvironmental regulation. The present study aimed to investigate the relationship between lactate-related genes (LRGs) and myocardial infarction (MI).

Methods

A total of 23 LRGs exhibited differential expression between individuals with MI and healthy controls. Lasso regression analysis and validation with the GSE61144 dataset identified three hub genes: COX20, AGK, and PDHX. Single-gene GSEA of these genes revealed strong enrichment in pathways related to amino acid metabolism, cell cycle, and immune functions. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was utilized to validate the expression levels of the hub genes.

Results

Immune infiltration analysis revealed differences in CD4+ T and CD8+ T cells between the MI and control groups. Additionally, 67 candidate drugs targeting the three hub LRGs were identified, and a ceRNA network was constructed to explore the intricate interactions among these genes.

Conclusions

These findings enhance the understanding of MI and have potential therapeutic implications.

Peripheral Perfusion Index in Ugandan Children With Plasmodium falciparum Severe Malaria: Secondary Analysis of Outcomes in a 2014-2017 Cohort Study

OBJECTIVES

Continuous, noninvasive tools to monitor peripheral perfusion, such as perfusion index (PI), can detect hemodynamic abnormalities and assist in the management of critically ill children hospitalized with severe malaria. In this study of hospitalized children with severe malaria, we aimed to assess whether PI correlates with clinical markers of perfusion and to determine whether combining PI with these clinical measures improves identification of children with greater odds of mortality.

DESIGN

Post hoc analysis of a prospective, multicenter, cohort study conducted between 2014 and 2017.

SETTING

Two referral hospitals in Central and Eastern Uganda.

PATIENTS

Six hundred children younger than 5 years old with severe malaria and 120 asymptomatic community children.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

PI was measured at 6-hour intervals for the first 24 hours of hospitalization. We compared PI to standard clinical perfusion measures such as capillary refill time, presence of cold peripheral limbs, or temperature gradient. Admission PI was highly correlated with clinical measures of perfusion. Admission PI was lower in children with severe malaria compared with asymptomatic community children; and, among the children with severe malaria, PI was lower in those with clinical features of poor perfusion or complications of severe malaria, such as shock and hyperlactatemia (all p < 0.02). Among children with severe malaria, lower admission PI was associated with greater odds of mortality after adjustment for age, sex, and severe malaria criteria (adjusted odds ratio, 2.4 for each log decrease in PI [95% CI, 1.0-5.9]; p = 0.045). Diagnostically, the presence of two consecutive low PI measures (< 1%) predicted mortality, with a sensitivity of 50% and a specificity of 76%.

CONCLUSIONS

In severe malaria, PI correlates with clinical complications (including shock and elevated serum lactate) and may be useful as an objective, continuous explanatory variable associated with greater odds of later in-hospital mortality.

Resuscitating the macro- vs. microcirculation in septic shock

PURPOSE OF REVIEW

This review summarizes current literature about the relationships between macro and microcirculation and their practical clinical implications in children with septic shock.

RECENT FINDINGS

Current evidence from experimental and clinical observational studies in children and adults with septic shock reveals that the response to treatment and resuscitation is widely variable. Furthermore, there is a loss of hemodynamic coherence, as resuscitation-induced improvement in macrocirculation (systemic hemodynamic parameters) does not necessarily result in a parallel improvement in the microcirculation. Therefore, patient-tailored monitoring is essential in order to adjust treatment requirements during resuscitation in septic shock. Optimal monitoring must integrate macrocirculation (heart rate, blood pressure, cardiac output, and ultrasound images), microcirculation (videomicroscopy parameters and capillary refill time) and cellular metabolism (lactic acid, central venous blood oxygen saturation, and difference of central venous to arterial carbon dioxide partial pressure).

SUMMARY

There is a dire need for high-quality studies to assess the relationships between macrocirculation, microcirculation and tissue metabolism in children with septic shock. The development of reliable and readily available microcirculation and tissue perfusion biomarkers (other than lactic acid) is also necessary to improve monitoring and treatment adjustment in such patients.

HEMORRHAGIC SHOCK ASSESSED BY TISSUE MICROCIRCULATORY MONITORING: A NARRATIVE REVIEW

ABSTRACT

Hemorrhagic shock (HS) is a common complication after traumatic injury. Early identification of HS can reduce patients' risk of death. Currently, the identification of HS relies on macrocirculation indicators such as systolic blood pressure and heart rate, which are easily affected by the body's compensatory functions. Recently, the independence of the body's overall macrocirculation from microcirculation has been demonstrated, and microcirculation indicators have been widely used in the evaluation of HS. In this study, we reviewed the progress of research in the literature on the use of microcirculation metrics to monitor shock. We analyzed the strengths and weaknesses of each metric and found that microcirculation monitoring could not only indicate changes in tissue perfusion before changes in macrocirculation occurred but also correct tissue perfusion and cell oxygenation after the macrocirculation index returned to normal following fluid resuscitation, which is conducive to the early prediction and prognosis of HS. However, microcirculation monitoring is greatly affected by individual differences and environmental factors. Therefore, the current limitations of microcirculation assessments mean that they should be incorporated as part of an overall assessment of HS patients. Future research should explore how to better combine microcirculation and macrocirculation monitoring for the early identification and prognosis of HS patients.

Pediatric Shock Review

Shock occurs when there is energy failure due to inadequate oxygen/glucose delivery to meet metabolic demands. Shock is a leading cause of death and disability in children worldwide. Types of shock include hypovolemic, cardiogenic, distributive, and obstructive. This review provides an overview of the epidemiology, pathophysiology, and clinical signs and symptoms of each of these types of shock, followed by a discussion of advancements in diagnostic tests and tools and management/treatment principles for different categories of shock.

Association Between Postresuscitation 12-Lead ECG Features and Early Mortality After Out-of-Hospital Cardiac Arrest: A Post Hoc Subanalysis of the PEACE Study

Background Once the return of spontaneous circulation after out-of-hospital cardiac arrest is achieved, a 12-lead ECG is strongly recommended to identify candidates for urgent coronary angiography. ECG has no apparent role in mortality risk stratification. We aimed to assess whether ECG features could be associated with 30-day survival in patients with out-of-hospital cardiac arrest. Methods and Results All the post-return of spontaneous circulation ECGs from January 2015 to December 2018 in 3 European centers (Pavia, Lugano, and Vienna) were collected. Prehospital data were collected according to the Utstein style. A total of 370 ECGs were collected: 287 men (77.6%) with a median age of 62 years (interquartile range, 53-70 years). After correction for the return of spontaneous circulation-to-ECG time, age >62 years (hazard ratio [HR], 1.78 [95% CI, 1.21-2.61]; P=0.003), female sex (HR, 1.5 [95% CI, 1.05-2.13]; P=0.025), QRS wider than 120 ms (HR, 1.64 [95% CI, 1.43-1.87]; P<0.001), the presence of a Brugada pattern (HR, 1.49 [95% CI, 1.39-1.59]; P<0.001), and the presence of ST-segment elevation in >1 segment (HR, 1.75 [95% CI, 1.59-1.93]; P<0.001) were independently associated with 30-day mortality. A score ranging from 0 to 26 was created, and by dividing the population into 3 tertiles, 3 classes of risk were found with significantly different survival rate at 30 days (score 0-4, 73%; score 5-7, 66%; score 8-26, 45%). Conclusions The post-return of spontaneous circulation ECG can identify patients who are at high risk of mortality after out-of-hospital cardiac arrest earlier than other forms of prognostication. This provides important risk stratification possibilities in postcardiac arrest care that could help to direct treatments and improve outcomes in patients with out-of-hospital cardiac arrest.

Blood pressure and flow in pediatric anesthesia: An educational review

During recent years, a lot of interest has been focused on blood pressure in the context of pediatric anesthesia, trying to define what is normal in relation to age and what numeric values that should be regarded as hypotension, needing active intervention. However, blood pressure is mainly measured as a proxy for flow, that is, cardiac output. Thus, just focusing on specific blood pressure numbers may not necessarily be very useful or appropriate. The aim of this educational review is to put the issue of intraoperative blood pressure in the context of pediatric anesthesia in further perspective.