Capillary refill time during fluid resuscitation in patients with sepsis-related hyperlactatemia at the emergency department is related to mortality

Capillary refill for the assessment of circulatory dysfunction in sepsis: A scoping review

BACKGROUND

Sepsis remains a significant and difficult diagnosis in US Emergency Departments and Intensive Care Units.

OBJECTIVE

The objective of this scoping review was to understand the state of the literature regarding the performance of Capillary Refill Time [CRT] as a method to assess circulatory dysfunction in sepsis.

DESIGN

This study followed PRISMA Guidelines for Scoping Reviews. Included studies used CRT as a physical exam finding 'measuring the time of return of color to a blanched nailbed' and was limited to Emergency Department and Intensive Care Unit settings. Our search used OVID Medline from 1946 through December of 2022 and resulted in 800 articles that led to 13 being included in the final analysis. Included studies were appraised using the Newcastle Ottawa Score.

RESULTS

Overall, the strength of the evidence across the 13 final studies was moderate. Studies suffered from numerous methodological shortcomings, and reproducibility in how they measured capillary refill.

CONCLUSION

Capillary refill has the potential to assist in the assessment of circulatory dysfunction in sepsis; however, emerging technologies making bedside measurement more reproducible and reliable must be further developed and studied in prospective randomized control trials powered to predict meaningful patient outcomes.

Emergency medicine updates: Management of sepsis and septic shock

INTRODUCTION

Sepsis is a common condition associated with significant morbidity and mortality. Emergency physicians play a key role in the diagnosis and management of this condition.

OBJECTIVE

This paper evaluates key evidence-based updates concerning the management of sepsis and septic shock for the emergency clinician.

DISCUSSION

Sepsis is a life-threatening syndrome, and rapid diagnosis and management are essential. Antimicrobials should be administered as soon as possible, as delays are associated with increased mortality. Resuscitation targets include mean arterial pressure ≥ 65 mmHg, mental status, capillary refill time, lactate, and urine output. Intravenous fluid resuscitation plays an integral role in those who are fluid responsive. Balanced crystalloids and normal saline are both reasonable options for resuscitation. Early vasopressors should be initiated in those who are not fluid-responsive. Norepinephrine is the recommended first-line vasopressor, and if hypotension persists, vasopressin should be considered, followed by epinephrine. Administration of vasopressors through a peripheral 20-gauge or larger intravenous line is safe and effective. Steroids such as hydrocortisone and fludrocortisone should be considered in those with refractory septic shock.

CONCLUSION

An understanding of the recent updates in the literature concerning sepsis and septic shock can assist emergency clinicians and improve the care of these patients.

Interfinger Differences in Pulse Oximetry Signal-Derived Peripheral Perfusion Index: A Single-Center Exploratory Study

INTRODUCTION

 Peripheral perfusion monitoring is crucial for the management of critically ill patients because abnormal peripheral perfusion is associated with a poor prognosis. The peripheral perfusion index (PPI), derived from pulse oximetry, quantifies peripheral perfusion but varies across fingers. A pulse oximeter probe may cause burns when worn at the same site. Therefore, changing the site has been recommended. However, changes in PPI values owing to probe replacement reduce the reliability of clinical and research applications. No two fingers with equivalent PPI values have been identified yet. This study assessed the interfinger differences in PPI by measuring the five fingers simultaneously and identified the two fingers with the least fluctuation in values.

METHODS

 A total of 30 healthy volunteers were included in this single-center prospective exploratory study. For PPI measurements, the pulse amplitude index (PAI) was measured using a pulse oximeter on a bedside monitor (Life Scope PT; Nihon Kohden Corp., Tokyo, Japan). The tape-type disposable pulse oximeter probes were attached to each of the five fingertips of the dominant hand, and measurements were conducted in three rooms with different temperatures (16°C, 22°C, and 28°C) to induce thermoregulatory responses and capture a wide range of PAI values. The primary endpoint was the PAI in pairs of two fingers each (a total of 10 pairs). Paired t-tests with Bonferroni correction were used to compare finger pairs, with statistical significance defined as p < 0.005.

RESULTS

The combination with the least difference in PAI was the index-ring finger combination (0.07% ± 1.89%, p = 0.74), followed by the middle-ring finger (0.45% ± 1.93%, p = 0.03) and index-middle finger combinations (0.52% ± 2.05%, p = 0.02). All other finger combinations showed statistically significant differences (p < 0.001).

CONCLUSION

 PPI values measured using the pulse oximeter showed the smallest interfinger difference between the index and ring fingers. If changing the finger to which the probe is attached during clinical or research use is needed, it may be possible to consistently measure the PPI values by alternately attaching the probe to the index and ring fingers.

A New Approach to Non-Invasive Microcirculation Monitoring: Quantifying Capillary Refill Time Using Oximetric Pulse Waves

(1) Background: To develop a novel capillary refill time measurement system and evaluate its reliability and reproducibility. (2) Methods: Firstly, the utilization of electromagnetic pressure technology facilitates the automatic compression and instantaneous release of the finger. Secondly, the employment of pressure sensing technology and photoelectric volumetric pulse wave analysis technology enables the dynamic monitoring of blood flow in distal tissues. Thirdly, the subjects were recruited to compare the average measurement time and the number of measurements required for successful measurements. The satisfaction of doctors and patients with the instrument was investigated through the administration of questionnaires. Finally, 71 subjects were recruited and divided into two groups, A and B. Three doctors repeated the measurement of the right index fingers of the subjects. In Group A, the same measuring instrument was used, and the consistency of the measurements was evaluated using the intragroup correlation coefficient. In Group B, one doctor repeated the measurement of each subject three times using the same measuring instrument, and the reproducibility of the CRT was evaluated using the analysis of variance of the repeated measurement data. (3) Results: The development of the capillary refill time meter was successful, with an average measurement time of 18 s and a single measurement. This study found that doctor-patient satisfaction levels were 98.3% and 100%, respectively. The intraclass correlation coefficient was 0.995 in Group A, and the p-value was greater than 0.05 in Group B. (4) Conclusions: The non-invasive monitoring of microcirculation has been rendered both rapid and effective, thus paving the way for the further mechanization and standardization of this process. The CRT, when measured using the capillary refill time meter test machine, demonstrated consistent and reproducible results, both when assessed by different researchers and when evaluated across varying measurement sets.

[Typical causes and clinical presentations of traumatic and nontraumatic soft tissue and organ haemorrhage in emergency departments]

Acute bleeding often occurs in a wide variety of forms in clinical emergency medicine. In traumatic bleeding, soft tissue injuries to the head or extremities are common, while severe bleeding is less common in chest injuries or pelvic trauma. In nontraumatic emergencies, gastrointestinal bleeding is the leading cause, but many other bleeding entities are possible. Structured management helps to detect the critically ill patient, identify the possible source of bleeding and provide appropriate radiological diagnostics and therapy. Clinical examination, blood gas analyses and emergency ultrasound are crucial in the initial phase of diagnosis. Initially, symptomatic therapy is usually indicated to stabilize the patient, and then interventional or surgical care is indicated in the course of the disease, depending on the location of the bleeding. Volume and catecholamine therapy, coagulation management and emergency transfusion are important components of interdisciplinary emergency care, in addition to primary bleeding control, especially in the case of open injuries.

Management of adult sepsis in resource-limited settings: global expert consensus statements using a Delphi method

PURPOSE

To generate consensus and provide expert clinical practice statements for the management of adult sepsis in resource-limited settings.

METHODS

An international multidisciplinary Steering Committee with expertise in sepsis management and including a Delphi methodologist was convened by the Asia Pacific Sepsis Alliance (APSA). The committee selected an international panel of clinicians and researchers with expertise in sepsis management. A Delphi process based on an iterative approach was used to obtain the final consensus statements.

RESULTS

A stable consensus was achieved for 30 (94%) of the statements by 41 experts after four survey rounds. These include consensus on managing patients with sepsis outside a designated critical care area, triggers for escalating clinical management and criteria for safe transfer to another facility. The experts agreed on the following: in the absence of serum lactate, clinical parameters such as altered mental status, capillary refill time and urine output may be used to guide resuscitation; special considerations regarding the volume of fluid used for resuscitation, especially in tropical infections, including the use of simple tests to assess fluid responsiveness when facilities for advanced hemodynamic monitoring are limited; use of Ringer's lactate or Hartmann's solution as balanced salt solutions; epinephrine when norepinephrine or vasopressin are unavailable; and the administration of vasopressors via a peripheral vein if central venous access is unavailable or not feasible. Similarly, where facilities for investigation are unavailable, there was consensus for empirical antimicrobial administration without delay when sepsis was strongly suspected, as was the empirical use of antiparasitic agents in patients with suspicion of parasitic infections.

CONCLUSION

Using a Delphi method, international experts reached consensus to generate expert clinical practice statements providing guidance to clinicians worldwide on the management of sepsis in resource-limited settings. These statements complement existing guidelines where evidence is lacking and add relevant aspects of sepsis management that are not addressed by current international guidelines. Future studies are needed to assess the effects of these practice statements and address remaining uncertainties.

Improving the early diagnosis and clinical outcomes of shock patients via laser speckle contrast imaging assessment of peripheral hemodynamics

Shock is defined as a critical circulatory failure that requires prompt diagnosis to optimize patient outcomes. Traditional diagnostic methods have limitations, including contact-based measurements, high costs, and lengthy procedures. The study evaluated the efficacy of laser speckle contrast imaging (LSCI), a noncontact technique, for assessing peripheral hemodynamics in shock patients. Results showed that LSCI accurately captured dynamic changes in blood flow, revealing early indicators of shock. ROI diff and ROI diff/ROI2 values significantly differed between shock patients and healthy controls. Spearman's correlation analysis revealed associations between ROI diff and key physiological parameters, such as blood pressure and heart rate. ROC analysis revealed that ROI diff and ROI diff/ROI2 had strong accuracy (72.5% and 82.5%, respectively) for detecting shock. Additionally, LSCI reduced testing time by over 50%, offering faster assessments. These findings demonstrate the potential of LSCI to improve diagnosis and management of shock, especially in complex clinical environments.

Peripheral and Organ Perfusion's Role in Prognosis of Disease Severity and Mortality in Severe COVID-19 Patients: Prospective Cohort Study

Severe COVID-19 is associated with a generalized inflammatory response leading to peripheral and organ perfusion disorders. Objectives: This study aimed to evaluate the usefulness of peripheral and organ perfusion assessments in the prediction of prognosis and mortality in patients with severe COVID-19. Patients and Methods: In the first 48 h of hospitalization, peripheral perfusion (saturation, Finger Infrared Thermography-FIT; Capillary Refill Time-CRT), and the color Doppler renal cortex perfusion (RCP) were estimated in a group of 102 severe COVID-19 patients. Results: In total, 40 patients experienced deterioration and required intensification of oxygen treatment, and 24 finally died. In comparison with a stable course of the disease, patients with deterioration had initially higher WBC, CRP, AST, LDH, and CRT, but a lower oxygenation ratio and RCP. Deceased patients were older, had higher CRP, LDH, and CRT, but lower hemoglobin, oxygenation ratio, and RCP compared to survivors. In the multivariable regression analysis from perfusion parameters, only RCP and CRT were independently linked with deterioration (OR 0.002, p < 0.001; OR 1.825, p = 0.003, respectively) and death (OR 0.001, p = 0.004; OR 1.910, p = 0.003, respectively). Conclusions: Initial assessment of peripheral and organ perfusion can be helpful in identifying hospitalized severe COVID-19 patients with a higher risk of deterioration and death. Capillary Refill Time and Renal Cortical Perfusion were prognostic markers of deterioration or death. On the other hand, Finger Infrared Thermography and saturation were not statistically significant in predicting patient outcome. An RCP cut-off value below 0.127 and 0.112 [cm/s] and a Capillary Refill Time longer than 3.25 and 4.25 [s] indicate the risk of deterioration or death, respectively.

Application of microcirculatory indicators in predicting the prognosis of patients with septic shock

Objective

The aim of this study is to investigate the predictive value of indicators associated with microcirculation, capillary refill time (CRT), perfusion index (PI), and mottling score, on the prognosis of patients with septic shock.

Method

A retrospective clinical study was conducted encompassing 78 patients diagnosed with septic shock and admitted to the Department of Critical Care Medicine at our hospital from January 2019 to January 2022. The study collated the clinical data of these patients, focusing on macrocirculatory hemodynamic parameters and microcirculatory indices. The parameters of interest were recorded at 0, 6, 24, and 48 h post-admission, including heart rate, mean arterial pressure (MAP), venous-to-arterial carbon dioxide partial pressure difference, superior vena cava oxygen saturation, lactic acid (LAC), CRT, PI, and mottling score. The enrolled patients were stratified into two cohorts based on the 28-day mortality rate: a survival group and a mortality group. A non-parametric statistical test was employed to compare the CRT, PI, and mottling score between the two groups. Furthermore, the predictive value of these microcirculatory indicators for mortality in septic shock patients was assessed using receiver operating characteristic (ROC) curve analysis. This methodology allowed for the evaluation of the prognostic accuracy of CRT, PI, and mottling score as indicators for mortality in the context of septic shock.

Results

The vasoactive drug dose, PI, LAC, mottling score, and CRT upon admission in the survival group were significantly better than those in the mortality group at hour 6 of treatment, hour 24 of treatment, and hour 48 of treatment (P < 0.05). The predictive value of the three microcirculatory indicators at various time points was highest for the Perfusion Index (PI) at 48 h of treatment, the mottling score at 24 h of treatment, and the Capillary Refill Time (CRT) upon admission. The Area Under the Curve (AUC) for PI at 48 h of treatment was 0.941 (0.885-0.996), with a sensitivity of 90.9 % and a specificity of 94.1 %. For the mottling score at 24 h of treatment, the AUC was 0.889 (0.805-0.972), with a sensitivity of 82.4 % and a specificity of 88.6 %. The AUC for CRT upon admission was 0.872 (0.788-0.956), with a sensitivity of 91.2 % and a specificity of 77.3 %. Among the three indicators: PI, mottling score, and CRT, PI at hour 48 of treatment had the highest predictive value for the prognosis of patients with septic shock.

Conclusion

Microcirculatory indicators have specific predictive value for the prognosis of patients with septic shock.

Obstetric sepsis: Clinical pearls for diagnosis and management

Sepsis is a leading cause of maternal morbidity and mortality worldwide. Early recognition and treatment improve outcomes. Multiple sepsis diagnostic screening tools are available and may be used in clinical practice; however, early thorough bedside evaluation of the patient is fundamental. Obstetricians should be able to recognize sepsis and promptly initiate potentially life-saving treatments, such as fluid resuscitation, vasopressors, broad-spectrum antibiotics, and early source control. It is recommended that obstetrical care, including delivery timing, not be altered solely due to the diagnosis of sepsis.

Perspectives for capillary refill time in clinical practice for sepsis

BACKGROUND

Capillary refill time (CRT) is defined as the time taken for color to return to an external capillary bed after pressure is applied to cause blanching. Recent studies demonstrated the benefits of CRT in guiding fluid therapy for sepsis. However, lack of consistency among physicians in how to perform and interpret CRT has led to a low interobserver agreement for this assessment tool, which prevents its availability in sepsis clinical settings.

OBJECTIVE

To give physicians a concise overview of CRT and explore recent evidence on its reliability and value in the management of sepsis.

RESEARCH DESIGN

A narrative review.

RESULTS

This narrative review summarizes the factors affecting CRT values, for example, age, sex, temperature, light, observation techniques, work experience, training level and differences in CRT measurement methods. The methods of reducing the variability of CRT are synthesized. Based on studies with highly reproducible CRT measurements and an excellent inter-rater concordance, we recommend the standardized CRT assessment method. The threshold of normal CRT values is discussed. The application of CRT in different phases of sepsis management is summarized.

CONCLUSIONS

Recent data confirm the value of CRT in critically ill patients. CRT should be detected by trained physicians using standardized methods and reducing the effect of ambient-related factors. Its association with severe infection, microcirculation, tissue perfusion response, organ dysfunction and adverse outcomes makes this approach a very attractive tool in sepsis. Further studies should confirm its value in the management of sepsis.

IMPLICATIONS FOR CLINICAL PRACTICE

As a simple assessment, CRT deserves more attention even though it has not been widely applied at the bedside. CRT could provide nursing staff with patient's microcirculatory status, which may help to develop individualized nursing plans and improve the patient's care quality and treatment outcomes.

Early peripheral perfusion monitoring in septic shock

Septic shock is a frequent critical clinical condition and a leading cause of death in critically ill individuals. However, it is challenging to identify affected patients early. In this article, we discuss new perspectives on the methods and uses of peripheral perfusion monitoring, considering the concept of a dysregulated response. Physical examination, and visual and ultrasonographic techniques are used to measure peripheral microcirculatory blood flow to reflect tissue perfusion. Compared with other monitoring techniques, peripheral perfusion monitoring has the benefits of low invasiveness and good repeatability, and allows for quick therapeutic judgments, which have significant practical relevance. Peripheral perfusion monitoring is an effective tool to detect early signs of septic shock, autonomic dysfunction, and organ damage. This method can also be used to evaluate treatment effectiveness, direct fluid resuscitation and the use of vasoactive medications, and monitor vascular reactivity, microcirculatory disorders, and endothelial cell damage. Recent introductions of novel peripheral perfusion monitoring methods, new knowledge of peripheral perfusion kinetics, and multimodal peripheral perfusion evaluation methods have occurred. To investigate new knowledge and therapeutic implications, we examined the methodological attributes and mechanisms of peripheral perfusion monitoring, in this study.

Capillary Refill Time as a Part of Routine Physical Examination in Critically Ill Patients Undergoing Vasoactive Therapy: A Prospective Study

Background/Objectives: In critically ill patients, achieving a mean arterial pressure (MAP) of 65 mmHg is a recommended resuscitation goal to ensure proper tissue oxygenation. Unfortunately, some patients do not benefit from providing such a value, suggesting that other indices are needed for better hemodynamic assessment. Capillary refill time (CRT) has emerged as an established marker for peripheral perfusion and a therapeutic target in critical illness, but its relationship with other exponents of hypoperfusion during vasopressor support after resuscitation period still warrants further research. This study aimed to investigate whether in critically ill patients after initial resuscitation, CRT would provide information independent of other, readily accessible hemodynamic variables. Methods: Critically ill patients who were mechanically ventilated after the resuscitation period and receiving vasopressors were prospectively studied between December 2022 and June 2023. Vasopressor support was measured using norepinephrine equivalent doses (NEDs). CRT, MAP and NED were assessed simultaneously and analyzed using Spearman's rank correlation. Results: A total of 92 patients were included and 210 combined MAP-CRT-NED-Lactate records were obtained. There was no correlation between CRT and MAP (R = -0.1, p = 0.14) or lactate (R = 0.11, p = 0.13), but there was a positive weak correlation between CRT and NED (R = 0.25, p = 0.0005). In patients with hypotension, in 83% of cases (15/18), CRT was within normal range, despite different doses of catecholamines. When assessing patients with high catecholamine doses, in 58% cases (11/19), CRT was normal and MAP was usually above 65 mmHg. Conclusions: Capillary refill time provides additional hemodynamic information that is not highly related with the values of mean arterial pressure, lactate level and vasopressor doses. It could be incorporated into routine physical examination in critically ill patients who are beyond initial resuscitation.

Can plethysmographic capillary refill time predict lactate during sepsis? An observational study from Morocco

Introduction

Blood lactate is a marker of tissue hypoxia while capillary refill time (CRT) is a surrogate of tissue perfusion. Measuring these parameters is recommended for assessing circulatory status and guiding resuscitation. However, blood lactate is not widely available in African emergency departments. Additionally, CRT assessment faces challenges related to its precision and reproducibility. This study aims to evaluate the accuracy of visual CRT(V-CRT) compared to plethysmographic CRT (P-CRT) in predicting lactate levels among septic patients.

Methods

This prospective observational study enrolled consecutive patients with sepsis or septic shock over a 6-month period from a tertiary hospital in Marrakech, Morroco. V-CRT and P-CRT were evaluated upon admission, and simultaneous measurements of arterial lactate levels were obtained. The precision of V-CRT and P-CRT in predicting arterial lactate was assessed using ROC curve analysis.

Results

Forty-three patients aged of 64±15 years, of whom 70 % were male, were included in the study. Of these, 23 patients (53 %) had sepsis, and 20 patients (47 %) experienced septic shock. Both V-CRT and P-CRT demonstrated statistically significant correlations with arterial lactate, with correlation coefficients of 0.529 (p < 0.0001) and 0.517 (p = 0.001), respectively. ROC curve analysis revealed that V-CRT exhibited satisfactory accuracy in predicting arterial lactate levels >2 mmol/l, with an area under the curve (AUC) of 0.8 (95 % CI=0.65 - 0.93; p < 0.0001). The prediction ability of P-CRT was lower than V-CRT with an AUC of 0.73 (95 % CI: 0.57-0.89; p = 0.043). The optimal thresholds were determined as 3.4 s for V-CRT (sensitivity = 90 %, specificity = 58 %) and 4.1 s for P-CRT (sensitivity = 85 %, specificity = 62 %).

Conclusion

These findings suggest that the plethysmographic evaluation did not improve the accuracy of CRT for predicting lactate level. However, V-CRT may still serve as a viable surrogate for lactate in septic patients in low-income settings.

The Indian Society of Critical Care Medicine Position Statement on the Management of Sepsis in Resource-limited Settings

Sepsis poses a significant global health challenge in low- and middle-income countries (LMICs). Several aspects of sepsis management recommended in international guidelines are often difficult or impossible to implement in resource-limited settings (RLS) due to issues related to cost, infrastructure, or lack of trained healthcare workers. The Indian Society of Critical Care Medicine (ISCCM) drafted a position statement for the management of sepsis in RLS focusing on India, facilitated by a task force of 18 intensivists using a Delphi process, to achieve consensus on various aspects of sepsis management which are challenging to implement in RLS. The process involved a comprehensive literature review, controlled feedback, and four iterative surveys conducted between 21 August 2023 and 21 September 2023. The domains addressed in the Delphi process included the need for a position statement, challenges in sepsis management, considerations for diagnosis, patient management while awaiting an intensive care unit (ICU) bed, and treatment of sepsis and septic shock in RLS. Consensus was achieved when 70% or more of the task force members voted either for or against statements using a Likert scale or a multiple-choice question (MCQ). The Delphi process with 100% participation of Task Force members in all rounds, generated consensus in 32 statements (91%) from which 20 clinical practice statements were drafted for the management of sepsis in RLS. The clinical practice statements will complement the existing international guidelines for the management of sepsis and provide valuable insights into tailoring sepsis interventions in the context of RLS, contributing to the global discourse on sepsis management. Future international guidelines should address the management of sepsis in RLS.

HOW TO CITE THIS ARTICLE

Juneja D, Nasa P, Chanchalani G, Cherian A, Jagiasi BG, Javeri Y, et al. The Indian Society of Critical Care Medicine Position Statement on the Management of Sepsis in Resource-limited Settings. Indian J Crit Care Med 2024;28(S2):S4-S19.

Prolonged capillary refill time and short-term mortality of critically ill patients: A meta-analysis

BACKGROUND

Prolonged capillary refill time (CRT) is an indicator of poor peripheral perfusion. The aim of the systematic review and meta-analysis was to evaluate the association of prolonged CRT and mortality of critically ill patients.

METHODS

To achieve the objective of this meta-analysis, we conducted a thorough search of PubMed, Embase, Cochrane Library, and the Web of Science to identify relevant observational studies with longitudinal follow-up. The Cochrane Q test was utilized to assess between-study heterogeneity, and the I2 statistic was calculated to estimate the degree of heterogeneity. We employed random-effects models to combine the outcomes, considering the potential influence of heterogeneity.

RESULTS

Eleven studies, encompassing 11,659 critically ill patients were included. During follow-up durations within hospitalization to 3 months, 1247 (10.7%) patients died. The pooled results indicated that a prolonged CRT at early phase of admission was significantly associated with an increased risk of all-cause mortality (risk ratio [RR]: 1.73, 95% confidence interval [CI]: 1.39 to 2.16, p < 0.001; I2 = 60%). Subgroup analyses showed that the association was not significantly modified by study design (prospective or retrospective), etiology of diseases (infection, non-infection, or mixed), or cutoff of CRT (>3 s, 3.5 s, or 4 s). The association between CRT and mortality was weaker in studies with multivariate analysis (RR: 1.43, 95% CI: 1.27 to 1.60, p < 0.001; I2 = 0%) as compared to that derived from studies of univariate analysis (RR: 6.27, 95% CI: 3.29 to 11.97, p < 0.001; I2 = 0%).

CONCLUSIONS

Prolonged CRT at admission may be a predictor of increased short-term mortality of critically ill patients.

Capillary refill time response to a fluid challenge or a vasopressor test: an observational, proof-of-concept study

BACKGROUND

Several studies have validated capillary refill time (CRT) as a marker of tissue hypoperfusion, and recent guidelines recommend CRT monitoring during septic shock resuscitation. Therefore, it is relevant to further explore its kinetics of response to short-term hemodynamic interventions with fluids or vasopressors. A couple of previous studies explored the impact of a fluid bolus on CRT, but little is known about the impact of norepinephrine on CRT when aiming at a higher mean arterial pressure (MAP) target in septic shock. We designed this observational study to further evaluate the effect of a fluid challenge (FC) and a vasopressor test (VPT) on CRT in septic shock patients with abnormal CRT after initial resuscitation. Our purpose was to determine the effects of a FC in fluid-responsive patients, and of a VPT aimed at a higher MAP target in chronically hypertensive fluid-unresponsive patients on the direction and magnitude of CRT response.

METHODS

Thirty-four septic shock patients were included. Fluid responsiveness was assessed at baseline, and a FC (500 ml/30 mins) was administered in 9 fluid-responsive patients. A VPT was performed in 25 patients by increasing norepinephrine dose to reach a MAP to 80-85 mmHg for 30 min. Patients shared a multimodal perfusion and hemodynamic monitoring protocol with assessments at at least two time-points (baseline, and at the end of interventions).

RESULTS

CRT decreased significantly with both tests (from 5 [3.5-7.6] to 4 [2.4-5.1] sec, p = 0.008 after the FC; and from 4.0 [3.3-5.6] to 3 [2.6 -5] sec, p = 0.03 after the VPT. A CRT-response was observed in 7/9 patients after the FC, and in 14/25 pts after the VPT, but CRT deteriorated in 4 patients on this latter group, all of them receiving a concomitant low-dose vasopressin.

CONCLUSIONS

Our findings support that fluid boluses may improve CRT or produce neutral effects in fluid-responsive septic shock patients with persistent hypoperfusion. Conversely, raising NE doses to target a higher MAP in previously hypertensive patients elicits a more heterogeneous response, improving CRT in the majority, but deteriorating skin perfusion in some patients, a fact that deserves further research.

Albumin versus saline infusion for sepsis-related peripheral tissue hypoperfusion: a proof-of-concept prospective study

BACKGROUND

Albumin has potential endothelial protective effects through antioxidant and anti-inflammatory properties. However, the effect of albumin on peripheral tissue perfusion in human sepsis remains poorly known.

METHODS

Bi-centric prospective study included patients with sepsis with or without shock and prolonged CRT > 3 s despite initial resuscitation. Clinicians in charge of the patients were free to infuse either saline 500 mL or human serum albumin 20% 100 mL over 15 min. Global hemodynamic parameters as well as peripheral tissue perfusion were analyzed after 1 (H1) and 4 h (H4). The primary endpoint was CRT normalization (< 3 s) at H1.

RESULTS

62 patients were screened, and 50 patients (13 sepsis and 37 septic shock) were included, 21 in the saline group and 29 in the albumin group. SOFA score was 8 [5-11], and SAPS II was 53 [45-70]. Median age was 68 [60-76] years with a higher proportion of men (74%). The primary sources of infection were respiratory (54%) and abdominal (24%). At baseline, comorbidities, clinical and biological characteristics were similar between groups. At H1, CRT normalization (< 3 s) was more frequent in patients receiving albumin as compared to patients treated by saline (63 vs 29%, P = 0.02). The decrease in fingertip CRT was more important in the albumin group when compared to saline group (- 1.0 [- 0.3; - 1.5] vs - 0.2 [- 0.1; - 1.1] seconds, P = 0.04) as well as decrease in mottling score. At H4, beneficial effects of albumin on peripheral tissue perfusion were maintained and urinary output trended to be higher in the albumin group (1.1 [0.5-1.8] vs 0.7 [0.5-0.9] ml/kg/h, P = 0.08). Finally, arterial lactate level did not significantly change between H0 and H4 in the saline group but significantly decreased in the albumin group (P = 0.03).

CONCLUSION

In patients with resuscitated sepsis, albumin infusion might lead to greater improvement of tissue hypoperfusion compared to saline.

CLINICALTRIALS

gov Identifier: NCT05094856.

Challenges in Septic Shock: From New Hemodynamics to Blood Purification Therapies

Sepsis and septic shock are associated with high mortality, with diagnosis and treatment remaining a challenge for clinicians. Their management classically encompasses hemodynamic resuscitation, antibiotic treatment, life support, and focus control; however, there are aspects that have changed. This narrative review highlights current and avant-garde methods of handling patients experiencing septic shock based on the experience of its authors and the best available evidence in a context of uncertainty. Following the first recommendation of the Surviving Sepsis Campaign guidelines, it is recommended that specific sepsis care performance improvement programs are implemented in hospitals, i.e., "Sepsis Code" programs, designed ad hoc, to achieve this goal. Regarding hemodynamics, the importance of perfusion and hemodynamic coherence stand out, which allow for the recognition of different phenotypes, determination of the ideal time for commencing vasopressor treatment, and the appropriate fluid therapy dosage. At present, this is not only important for the initial timing, but also for de-resuscitation, which involves the early weaning of support therapies, directed elimination of fluids, and fluid tolerance concept. Finally, regarding blood purification therapies, those aimed at eliminating endotoxins and cytokines are attractive in the early management of patients in septic shock.

Towards the personalization of septic shock resuscitation: the fundamentals of ANDROMEDA-SHOCK-2 trial

Septic shock is a highly lethal and prevalent disease. Progressive circulatory dysfunction leads to tissue hypoperfusion and hypoxia, eventually evolving to multiorgan dysfunction and death. Prompt resuscitation may revert these pathogenic mechanisms, restoring oxygen delivery and organ function. High heterogeneity exists among the determinants of circulatory dysfunction in septic shock, and current algorithms provide a stepwise and standardized approach to conduct resuscitation. This review provides the pathophysiological and clinical rationale behind ANDROMEDA-SHOCK-2, an ongoing multicenter randomized controlled trial that aims to compare a personalized resuscitation strategy based on clinical phenotyping and peripheral perfusion assessment, versus standard of care, in early septic shock resuscitation.

The association between prolonged capillary refill time and microcirculation changes in children with sepsis

BACKGROUNDS

In children with sepsis, circulatory shock and multi-organ failure remain major contributors to mortality. Prolonged capillary refill time (PCRT) is a clinical tool associated with disease severity and tissue hypoperfusion. Microcirculation assessment with videomicroscopy represents a promising candidate for assessing and improving hemodynamic management strategies in children with sepsis. Particularly when there is loss of coherence between the macro and microcirculation (hemodynamic incoherence). We sought to evaluate the association between PCRT and microcirculation changes in sepsis.

METHODS

This was a prospective cohort study in children hospitalized with sepsis. Microcirculation was measured using sublingual video microscopy (capillary density and flow and perfused boundary region [PBR]-a parameter inversely proportional to vascular endothelial glycocalyx thickness), phalangeal tissue perfusion, and endothelial activation and glycocalyx injury biomarkers. The primary outcome was the association between PCRT and microcirculation changes.

RESULTS

A total of 132 children with sepsis were included, with a median age of two years (IQR 0.6-12.2). PCRT was associated with increased glycocalyx degradation (PBR 2.21 vs. 2.08 microns; aOR 2.65, 95% CI 1.09-6.34; p = 0.02) and fewer 4-6 micron capillaries recruited (p = 0.03), with no changes in the percentage of capillary blood volume (p = 0.13). Patients with hemodynamic incoherence had more PBR abnormalities (78.4% vs. 60.8%; aOR 2.58, 95% CI 1.06-6.29; p = 0.03) and the persistence of these abnormalities after six hours was associated with higher mortality (16.5% vs. 6.1%; p < 0.01). Children with an elevated arterio-venous CO2 difference (DCO2) had an abnormal PBR (aOR 1.13, 95% CI 1.01-1.26; p = 0.03) and a lower density of small capillaries (p < 0.05). Prolonged capillary refill time predicted an abnormal PBR (AUROC 0.81, 95% CI 0.64-0.98; p = 0.03) and relative percentage of blood in the capillaries (AUROC 0.82, 95% CI 0.58-1.00; p = 0.03) on admission. A normal CRT at 24 h predicted a shorter hospital stay (aOR 0.96, 95% CI 0.94-0.99; p < 0.05).

CONCLUSIONS

We found an association between PCRT and microcirculation changes in children with sepsis. These patients had fewer small capillaries recruited and more endothelial glycocalyx degradation. This leads to nonperfused capillaries, affecting oxygen delivery to the tissues. These disorders were associated with hemodynamic incoherence and worse clinical outcomes when the CRT continued to be abnormal 24 h after admission.

Perfusion Index Variations in Children With Septic Shock: Single-Center Observational Cohort Study in India

OBJECTIVES

To study in children with septic shock: 1) variation in peripheral perfusion index (PI), which is a derived variable from pulse oximetry; 2) correlation between PI and lactate concentration; and 3) exploratory diagnostic evaluation between mortality and PI.

DESIGN

Prospective observational study (from October 2018 to March 2020).

SETTING

Pediatric emergency department and PICU of a tertiary hospital in India.

PATIENTS

Children (1 mo to 16 yr old) with septic shock.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Data collected included demographic, clinical, laboratory, and outcome-related variables. Hemodynamic variables like heart rate, mean arterial pressure, and PI, along with serum lactate were recorded at specified intervals. A total of 112 children with septic shock were recruited, with median (interquartile range [IQR]) age of 50 (IQR 12,118.5) months and 65 of 112 (58%) were male children. Overall mortality was 25 of 112 (22%). At admission, the median PI was 0.6 (IQR -0.30, 0.93), and we used PI less than or equal to 0.6 to define a "critical PI." Of 61 children with critical PI at admission, 26 of 61 increased above this threshold by 6 hours. We observed a negative correlation between PI and lactate, at admission ( r = -0.27; 95% CI, -0.44 to -0.08; p = 0.006) and at 6 hours ( r = -0.21; 95% CI, -0.39 to -0.02; p = 0.03). In the exploratory analysis, a PI cutoff of less than or equal to 0.6 at 6 hours had area under the receiver operating curve of 0.74 (95% CI, 0.60-0.88). That is, with a 70% sensitivity and 81% specificity for mortality, the performance of such a test in our population (pre-to-post-test probability) for mortality would be 0.22-0.51.

CONCLUSIONS

We have used pulse oximetry-derived PI in children presenting with septic shock and found that the value is negatively correlated with a rise in serum lactate concentration. However, the utility of using a critical threshold value in PI (≤ 0.6) after 6 hours of treatment to be indicative of later mortality has considerable uncertainty.

Prognostic value of capillary refill time in adult patients: a systematic review with meta-analysis

PURPOSE

Acute circulatory failure leads to tissue hypoperfusion. Capillary refill time (CRT) has been widely studied, but its predictive value remains debated. We conducted a meta-analysis to assess the ability of CRT to predict death or adverse events in a context at risk or confirmed acute circulatory failure in adults.

METHOD

MEDLINE, EMBASE, and Google scholar databases were screened for relevant studies. The pooled area under the ROC curve (AUC ROC), sensitivity, specificity, threshold, and diagnostic odds ratio using a random-effects model were determined. The primary analysis was the ability of abnormal CRT to predict death in patients with acute circulatory failure. Secondary analysis included the ability of CRT to predict death or adverse events in patients at risk or with confirmed acute circulatory failure, the comparison with lactate, and the identification of explanatory factors associated with better accuracy.

RESULTS

A total of 60,656 patients in 23 studies were included. Concerning the primary analysis, the pooled AUC ROC of 13 studies was 0.66 (95%CI [0.59; 0.76]), and pooled sensitivity was 54% (95%CI [43; 64]). The pooled specificity was 72% (95%CI [55; 84]). The pooled diagnostic odds ratio was 3.4 (95%CI [1.4; 8.3]). Concerning the secondary analysis, the pooled AUC ROC of 23 studies was 0.69 (95%CI [0.65; 0.74]). The prognostic value of CRT compared to lactate was not significantly different. High-quality CRT was associated with a greater accuracy.

CONCLUSION

CRT poorly predicted death and adverse events in patients at risk or established acute circulatory failure. Its accuracy is greater when high-quality CRT measurement is performed.

Clinical evaluation of peripheral tissue perfusion as a predictor of mortality in sepsis and septic shock in the intensive care unit: Systematic review and meta-analysis

OBJECTIVE

To determine the diagnostic performance of the clinical evaluation of peripheral tissue perfusion in the prediction of mortality.

DESIGN

Systematic review and meta-analysis.

SETTING

Intensive care unit.

PATIENTS AND PARTICIPANTS

Patients with sepsis and septic shock.

INTERVENTIONS

Studies of patients with sepsis and/or septic shock that associated clinical monitoring of tissue perfusion with mortality were included. A systematic review was performed by searching the PubMed/MEDLINE, Cochrane Library, SCOPUS, and OVID databases.

MAIN VARIABLES OF INTEREST

The risk of bias was assessed with the QUADAS-2 tool. Sensitivity and specificity were calculated to evaluate the predictive accuracy for mortality. Review Manager software version 5.4 was used to draw the forest plot graphs, and Stata version 15.1 was used to build the hierarchical summary receiver operating characteristic model.

RESULTS

Thirteen studies were included, with a total of 1667 patients and 17 analyses. Two articles evaluated the temperature gradient, four evaluated the capillary refill time, and seven evaluated the mottling in the skin. In most studies, the outcome was mortality at 14 or 28 days. The pooled sensitivity of the included studies was 70%, specificity 75.9% (95% CI, 61.6%-86.2%), diagnostic odds ratio 7.41 (95% CI, 3.91-14.04), and positive and negative likelihood ratios 2.91 (95% CI, 1.80-4.72) and 0.39 (95% CI, 0.30-0.51), respectively.

CONCLUSIONS

Clinical evaluation of tissue perfusion at the bedside is a useful tool, with moderate sensitivity and specificity, to identify patients with a higher risk of death among those with sepsis and septic shock.

REGISTRATION

PROSPERO CRD42019134351.

Ultrasonographic measurement of caudal vena cava to aorta ratio during fluid resuscitation of dogs with spontaneous circulatory shock

OBJECTIVES

To describe the change in the caudal vena cava to aorta ratio (CVC:Ao) ratio during fluid resuscitation of circulatory shock in dogs and compare these results with those of the physical examination and blood lactate.

MATERIALS AND METHODS

Perfusion parameters and blood lactate were recorded at admission. An abdominal point-of-care ultrasound protocol was performed, during which the caudal vena cava to aorta ratio was measured on the spleno-renal view. Measurements were performed within 5 minutes before and after a 10 mL/kg crystalloid fluid bolus. Investigators were not blinded to therapeutic interventions.

RESULTS

Twenty-nine dogs with physical signs of circulatory shock were enrolled. Caudal vena cava to aorta ratios were below reference interval in 28 of 29 dogs. After bolus administration, median caudal vena cava diameter increased by 0.14 cm (0.69 to 0.83 cm) and median aorta diameter increased by 0.03 cm (0.87 to 0.90 cm) and caudal vena cava to aorta ratio returned to within reference range in 65% of dogs (13/29). Bolus administration was associated with an increase in median caudal vena cava to aorta ratio of 0.10 (95% CI:0.05 to 0.16, P=0.0005). Blood lactate did not change significantly. Heart rate and capillary refill time decreased significantly after fluid bolus (heart rate: estimate=-19 bpm, 95% CI:-30 to -8, P=0.002; capillary refill time: estimate=-1.0 s, 95% CI:-1.3 to -0.7, P < 0.0001).

CLINICAL SIGNIFICANCE

In this population of dogs with circulatory shock, the caudal vena cava to aorta ratio significantly increased after a fluid bolus. Future studies that implement blinding of the outcome assessors are warranted to confirm these findings.

Development and validation of a nomogram to predict the risk of renal replacement therapy among acute kidney injury patients in intensive care unit

BACKGROUND

There are no universally accepted indications to initiate renal replacement therapy (RRT) among patients with acute kidney injury (AKI). This study aimed to develop a nomogram to predict the risk of RRT among AKI patients in intensive care unit (ICU).

METHODS

In this retrospective cohort study, we extracted AKI patients from Medical Information Mart for Intensive Care III (MIMIC-III) database. Patients were randomly divided into a training cohort (70%) and a validation cohort (30%). Multivariable logistic regression based on Akaike information criterion was used to establish the nomogram. The discrimination and calibration of the nomogram were evaluated by Harrell's concordance index (C-index) and Hosmer-Lemeshow (HL) test. Decision curve analysis (DCA) was performed to evaluate clinical application.

RESULTS

A total of 7413 critically ill patients with AKI were finally enrolled. 514 (6.9%) patients received RRT after ICU admission. 5194 (70%) patients were in the training cohort and 2219 (30%) patients were in the validation cohort. Nine variables, namely, age, hemoglobin, creatinine, blood urea nitrogen and lactate at AKI detection, comorbidity of congestive heart failure, AKI stage, and vasopressor use were included in the nomogram. The predictive model demonstrated satisfying discrimination and calibration with C-index of 0.938 (95% CI, 0.927-0.949; HL test, P = 0.430) in training set and 0.935 (95% CI, 0.919-0.951; HL test, P = 0.392) in validation set. DCA showed a positive net benefit of our nomogram.

CONCLUSION

The nomogram developed in this study was highly accurate for RRT prediction with potential application value.

Society for Maternal-Fetal Medicine Consult Series #67: Maternal sepsis

Maternal sepsis is a significant cause of maternal morbidity and mortality, and is a potentially preventable cause of maternal death. This Consult aims to summarize what is known about sepsis and provide guidance for the management of sepsis during pregnancy and the postpartum period. Most studies cited are from the nonpregnant population, but where available, pregnancy data are included. The following are the Society for Maternal-Fetal Medicine recommendations: (1) we recommend that clinicians consider the diagnosis of sepsis in pregnant or postpartum patients with otherwise unexplained end-organ damage in the presence of a suspected or confirmed infectious process, regardless of the presence of fever (GRADE 1C); (2) we recommend that sepsis and septic shock in pregnancy be considered medical emergencies and that treatment and resuscitation begin immediately (Best Practice); (3) we recommend that hospitals and health systems use a performance improvement program for sepsis in pregnancy with sepsis screening tools and metrics (GRADE 1B); (4) we recommend that institutions develop their own procedures and protocols for the detection of maternal sepsis, avoiding the use of a single screening tool alone (GRADE 1B); (5) we recommend obtaining tests to evaluate for infectious and noninfectious causes of life-threatening organ dysfunction in pregnant and postpartum patients with possible sepsis (Best Practice); (6) we recommend that an evaluation for infectious causes in pregnant or postpartum patients in whom sepsis is suspected or identified includes appropriate microbiologic cultures, including blood, before starting antimicrobial therapy, as long as there are no substantial delays in timely administration of antibiotics (Best Practice); (7) we recommend obtaining a serum lactate level in pregnant or postpartum patients in whom sepsis is suspected or identified (GRADE 1B); (8) in pregnant or postpartum patients with septic shock or a high likelihood of sepsis, we recommend administration of empiric broad-spectrum antimicrobial therapy, ideally within 1 hour of recognition (GRADE 1C); (9) after a diagnosis of sepsis in pregnancy is made, we recommend rapid identification or exclusion of an anatomic source of infection and emergency source control when indicated (Best Practice); (10) we recommend early intravenous administration (within the first 3 hours) of 1 to 2 L of balanced crystalloid solutions in sepsis complicated by hypotension or suspected organ hypoperfusion (GRADE 1C); (11) we recommend the use of a balanced crystalloid solution as a first-line fluid for resuscitation in pregnant and postpartum patients with sepsis or septic shock (GRADE 1B); (12) we recommend against the use of starches or gelatin for resuscitation in pregnant and postpartum patients with sepsis or septic shock (GRADE 1A); (13) we recommend ongoing, detailed evaluation of the patient's response to fluid resuscitation guided by dynamic measures of preload (GRADE 1B); (14) we recommend the use of norepinephrine as the first-line vasopressor during pregnancy and the postpartum period with septic shock (GRADE 1C); (15) we suggest using intravenous corticosteroids in pregnant or postpartum patients with septic shock who continue to require vasopressor therapy (GRADE 2B); (16) because of an increased risk of venous thromboembolism in sepsis and septic shock, we recommend the use of pharmacologic venous thromboembolism prophylaxis in pregnant and postpartum patients in septic shock (GRADE 1B); (17) we suggest initiating insulin therapy at a glucose level >180 mg/dL in critically ill pregnant patients with sepsis (GRADE 2C); (18) if a uterine source for sepsis is suspected or confirmed, we recommend prompt delivery or evacuation of uterine contents to achieve source control, regardless of gestational age (GRADE 1C); and (19) because of an increased risk of physical, cognitive, and emotional problems in survivors of sepsis and septic shock, we recommend ongoing comprehensive support for pregnant and postpartum sepsis survivors and their families (Best Practice).

Correlation Between Mean Arterial Pressure and Capillary Refill Time in Patients with Septic Shock: A Systematic Review and Meta-analysis

Background: The initial hemodynamic goal during septic shock resuscitation is to achieve a mean arterial pressure (MAP) above 65 mm Hg, although this does not assure a normal tissue perfusion. Capillary refill time (CRT), a marker of skin blood flow, has been validated as a marker of the reperfusion process. The aim of the study was to explore the relationship between MAP and CRT in patients in septic shock. Methods: We systematically reviewed studies which reported CRT and MAP in septic shock patients. Authors of eligible studies were asked to provide necessary data for performing a meta-correlation of Spearman's rank correlation coefficients. Subgroup analyses were performed, including studies of good quality and studies with higher/lower norepinephrine doses. Results: We identified 10 studies, comprising 917 patients. There were 5 studies considered to be of good quality. A meta-correlation showed a statistically significant but poor negative correlation between MAP and CRT (R = -0.158, range -0.221 to -0.093, P < .001, I2 = 0.0%). Subgroup analysis of best-quality studies gave similar results (R = -0.201, range -0.282 to -0.116, P < .001, I2 = 0.0%). In subanalysis concerning norepinephrine doses, no significant correlations were found. Conclusions: In patients with septic shock, there is poor inverse correlation between MAP and CRT. MAP > 65 mm Hg does not guarantee normalization of CRT.Registration code: PROSPERO: CRD42022355996. Registered on 5 September 2022.

Subclinical cardiac dysfunction may impact on fluid and vasopressor administration during early resuscitation of septic shock

BACKGROUND

According to the Surviving Sepsis Campaign (SSC) fluids and vasopressors are the mainstays of early resuscitation of septic shock while inotropes are indicated in case of tissue hypoperfusion refractory to fluids and vasopressors, suggesting severe cardiac dysfunction. However, septic cardiac disfunction encompasses a large spectrum of severities and may remain "subclinical" during early resuscitation. We hypothesized that "subclinical" cardiac dysfunction may nevertheless influence fluid and vasopressor administration during early resuscitation. We retrospectively reviewed prospectically collected data on fluids and vasoconstrictors administered outside the ICU in patients with septic shock resuscitated according to the SSC guidelines that had reached hemodynamic stability without the use of inotropes. All the patients were submitted to transpulmonary thermodilution (TPTD) hemodynamic monitoring at ICU entry. Subclinical cardiac dysfunction was defined as a TPTD-derived cardiac function index (CFI) ≤ 4.5 min-1.

RESULTS

At ICU admission, subclinical cardiac dysfunction was present in 17/40 patients (42%; CFI 3.6 ± 0.7 min-1 vs 6.6 ± 1.9 min-1; p < 0.01). Compared with patients with normal CFI, these patients had been resuscitate with more fluids (crystalloids 57 ± 10 vs 47 ± 9 ml/kg PBW; p < 0.01) and vasopressors (norepinephrine 0.65 ± 0.25 vs 0.43 ± 0.29 mcg/kg/min; p < 0.05). At ICU admission these patients had lower cardiac index (2.2 ± 0.6 vs 3.6 ± 0.9 L/min/m2, p < 0.01) and higher systemic vascular resistances (2721 ± 860 vs 1532 ± 480 dyn*s*cm-5/m2, p < 0.01).

CONCLUSIONS

In patients with septic shock resuscitated according to the SSC, we found that subclinical cardiac dysfunction may influence the approach to fluids and vasopressor administration during early resuscitation. Our data support the implementation of early, bedside assessment of cardiac function during early resuscitation of septic shock.

Comparison between Capillary and Serum Lactate Levels in Predicting Short-Term Mortality of Septic Patients at the Emergency Department

Sepsis is a time-dependent and life-threating condition related to macro- and micro-circulatory impairment leading to anaerobic metabolism and lactate increase. We assessed the prognostic accuracy of capillary lactates (CLs) vs. serum ones (SLs) on 48-h and 7-day mortality in patients with suspected sepsis. This observational, prospective, single-centre study was conducted between October 2021 and May 2022. Inclusion criteria were: (i) suspect of infection; (ii) qSOFA ≥ 2; (iii) age ≥ 18 years; (iv) signed informed consent. CLs were assessed with LactateProTM2^®. 203 patients were included: 19 (9.3%) died within 48 h from admission to the Emergency Department, while 28 (13.8%) within 7 days. Patients deceased within 48 h (vs. survived) had higher CLs (19.3 vs. 5 mmol/L, p < 0.001) and SLs (6.5 vs. 1.1 mmol/L, p = 0.001). The best CLs predictive cut-off for 48-h mortality was 16.8 mmol/L (72.22% sensitivity, 94.02% specificity). Patients within 7 days had higher CLs (11.5 vs. 5 mmol/L, p = 0.020) than SLs (2.75 vs. 1.1 mmol/L, p < 0.001). The multivariate analysis confirmed CLs and SLs as independent predictors of 48-h and 7-day mortality. CLs can be a reliable tool for their inexpensiveness, rapidity and reliability in identifying septic patients at high risk of short-term mortality.

Modifications of peripheral perfusion in patients with vasopressor-dependent septic shock treated with polymyxin B-direct hemoperfusion

Abnormal peripheral perfusion (PP) worsens the prognosis of patients with septic shock. Polymyxin B-direct hemoperfusion (PMX-DHP) increases blood pressure and reduces vasopressor doses. However, the modification of PP following administration of PMX-DHP in patients with vasopressor-dependent septic shock have not yet been elucidated. A retrospective exploratory observational study was conducted in patients with septic shock treated with PMX-DHP. Pulse-amplitude index (PAI), vasoactive inotropic score (VIS), and cumulative fluid balance data were extracted at PMX-DHP initiation (T0) and after 24 (T24) and 48 (T48) h. Changes in these data were analyzed in all patients and two subgroups (abnormal PP [PAI < 1] and normal PP [PAI ≥ 1]) based on the PAI at PMX-DHP initiation. Overall, 122 patients (abnormal PP group, n = 67; normal PP group, n = 55) were evaluated. Overall and in the abnormal PP group, PAI increased significantly at T24 and T48 compared with that at T0, with a significant decrease in VIS. Cumulative 24-h fluid balance after PMX-DHP initiation was significantly higher in the abnormal PP group. PMX-DHP may be an effective intervention to improve PP in patients with abnormal PP; however, caution should be exercised as fluid requirements may differ from that of patients with normal PP.

Novelties in the evaluation of microcirculation in septic shock

Microvascular alterations were first described in critically ill patients about 20 years ago. These alterations are characterized by a decrease in vascular density and presence of non-perfused capillaries close to well-perfused vessels. In addition, heterogeneity in microvascular perfusion is a key finding in sepsis. In this narrative review, we report our actual understanding of microvascular alterations, their role in the development of organ dysfunction, and the implications for outcome. Herein, we discuss the state of the potential therapeutic interventions and the potential impact of novel therapies. We also discuss how recent technologic development may affect the evaluation of microvascular perfusion.

Cohort profile of PLUTO: a perioperative biobank focusing on prediction and early diagnosis of postoperative complications

PURPOSE

Although elective surgery is generally safe, some procedures remain associated with an increased risk of complications. Improved preoperative risk stratification and earlier recognition of these complications may ameliorate postoperative recovery and improve long-term outcomes. The perioperative longitudinal study of complications and long-term outcomes (PLUTO) cohort aims to establish a comprehensive biorepository that will facilitate research in this field. In this profile paper, we will discuss its design rationale and opportunities for future studies.

PARTICIPANTS

Patients undergoing elective intermediate to high-risk non-cardiac surgery are eligible for enrolment. For the first seven postoperative days, participants are subjected to daily bedside visits by dedicated observers, who adjudicate clinical events and perform non-invasive physiological measurements (including handheld spirometry and single-channel electroencephalography). Blood samples and microbiome specimens are collected at preselected time points. Primary study outcomes are the postoperative occurrence of nosocomial infections, major adverse cardiac events, pulmonary complications, acute kidney injury and delirium/acute encephalopathy. Secondary outcomes include mortality and quality of life, as well as the long-term occurrence of psychopathology, cognitive dysfunction and chronic pain.

FINDINGS TO DATE

Enrolment of the first participant occurred early 2020. During the inception phase of the project (first 2 years), 431 patients were eligible of whom 297 patients consented to participate (69%). Observed event rate was 42% overall, with the most frequent complication being infection.

FUTURE PLANS

The main purpose of the PLUTO biorepository is to provide a framework for research in the field of perioperative medicine and anaesthesiology, by storing high-quality clinical data and biomaterials for future studies. In addition, PLUTO aims to establish a logistical platform for conducting embedded clinical trials.

TRIAL REGISTRATION NUMBER

NCT05331118.

Relationship between peripheral ischemic microvascular reserve, persistent hyperlactatemia, and its temporal dynamics in sepsis: a post hoc study

OBJECTIVE

To measure the prognostic value of peripheral ischemic microvascular reserve in the context of persistent sepsis-induced hyperlactatemia and measure its influence on the temporal dynamics of lactate and the strength of association between these variables.

METHODS

This post hoc analysis of the peripheral perfusion index/postocclusive reactive hyperemia trial, an observational cohort study that enrolled patients with sepsis who persisted with lactate levels ≥ 2mmol/L after fluid resuscitation (with or without shock). Peripheral ischemic microvascular reserve was evaluated using the association of the peripheral perfusion index and postocclusive reactive hyperemia techniques. The cutoff point of ∆ peripheral perfusion index peak values (%) defined the groups with low (≤ 62%) and high peripheral ischemic microvascular reserve (> 62%).

RESULTS

A total of 108 consecutive patients with persistent sepsis-induced hyperlactatemia were studied. The high peripheral ischemic microvascular reserve group showed higher 28-day mortality than the low peripheral ischemic microvascular reserve group (p < 0.01). The temporal dynamics of lactate within the first 48 hours showed a rapid decrease in lactate levels in the low peripheral ischemic microvascular reserve group (p < 0.01). However, this result was not reproduced in the linear mixed effects model. A weak correlation between peripheral ischemic microvascular reserve (%) and lactate level (mmol/L) was observed within the first 24 hours (r = 0.23; p < 0.05).

CONCLUSION

The prognostic value of high peripheral ischemic microvascular reserve was confirmed in the context of persistent sepsis-induced hyperlactatemia. Although there was a weak positive correlation between peripheral ischemic microvascular reserve value and lactate level within the first 24 hours of sepsis diagnosis, the low peripheral ischemic microvascular reserve group appeared to have a faster decrease in lactate over the 48 hours of follow-up.

Agreement between Capillary Refill Time measured at Finger and Earlobe sites in different positions: a pilot prospective study on healthy volunteers

BACKGROUND

Capillary Refill Time (CRT) is a marker of peripheral perfusion usually performed at fingertip; however, its evaluation at other sites/position may be advantageous. Moreover, arm position during CRT assessment has not been fully standardized.

METHODS

We performed a pilot prospective observational study in 82 healthy volunteers. CRT was assessed: a) in standard position with participants in semi-recumbent position; b) at 30° forearm elevation, c and d) at earlobe site in semi-recumbent and supine position. Bland-Altman analysis was performed to calculate bias and limits of agreement (LoA). Correlation was investigated with Pearson test.

RESULTS

Standard finger CRT values (1.04 s [0.80;1.39]) were similar to the earlobe semi-recumbent ones (1.10 s [0.90;1.26]; p = 0.52), with Bias 0.02 ± 0.18 s (LoA -0.33;0.37); correlation was weak but significant (r = 0.28 [0.7;0.47]; p = 0.01). Conversely, standard finger CRT was significantly longer than earlobe supine CRT (0.88 s [0.75;1.06]; p < 0.001) with Bias 0.22 ± 0.4 s (LoA -0.56;1.0), and no correlation (r = 0,12 [-0,09;0,33]; p = 0.27]. As compared with standard finger CRT, measurement with 30° forearm elevation was significantly longer (1.17 s [0.93;1.41] p = 0.03), with Bias -0.07 ± 0.3 s (LoA -0.61;0.47) and with a significant correlation of moderate degree (r = 0.67 [0.53;0.77]; p < 0.001).

CONCLUSIONS

In healthy volunteers, the elevation of the forearm significantly prolongs CRT values. CRT measured at the earlobe in semi-recumbent position may represent a valid surrogate when access to the finger is not feasible, whilst earlobe CRT measured in supine position yields different results. Research is needed in critically ill patients to evaluate accuracy and precision at different sites/positions.

Evidence-based updates to the 2021 Surviving Sepsis Campaign guidelines Part 2: Guideline review and clinical application

ABSTRACT

NPs should be prepared to screen for sepsis, initiate treatment, and optimize care for sepsis survivors. The 2021 Surviving Sepsis Campaign guidelines offer best practices for identification and management of sepsis and septic shock. This article, second in a 2-part series, presents evidence updates and discusses implications for NPs.

Pathophysiology of fluid administration in critically ill patients

Fluid administration is a cornerstone of treatment of critically ill patients. The aim of this review is to reappraise the pathophysiology of fluid therapy, considering the mechanisms related to the interplay of flow and pressure variables, the systemic response to the shock syndrome, the effects of different types of fluids administered and the concept of preload dependency responsiveness. In this context, the relationship between preload, stroke volume (SV) and fluid administration is that the volume infused has to be large enough to increase the driving pressure for venous return, and that the resulting increase in end-diastolic volume produces an increase in SV only if both ventricles are operating on the steep part of the curve. As a consequence, fluids should be given as drugs and, accordingly, the dose and the rate of administration impact on the final outcome. Titrating fluid therapy in terms of overall volume infused but also considering the type of fluid used is a key component of fluid resuscitation. A single, reliable, and feasible physiological or biochemical parameter to define the balance between the changes in SV and oxygen delivery (i.e., coupling "macro" and "micro" circulation) is still not available, making the diagnosis of acute circulatory dysfunction primarily clinical.

ISCCM Guidelines for Hemodynamic Monitoring in the Critically Ill

Hemodynamic assessment along with continuous monitoring and appropriate therapy forms an integral part of management of critically ill patients with acute circulatory failure. In India, the infrastructure in ICUs varies from very basic facilities in smaller towns and semi-urban areas, to world-class, cutting-edge technology in corporate hospitals, in metropolitan cities. Surveys and studies from India suggest a wide variation in clinical practices due to possible lack of awareness, expertise, high costs, and lack of availability of advanced hemodynamic monitoring devices. We, therefore, on behalf of the Indian Society of Critical Care Medicine (ISCCM), formulated these evidence-based guidelines for optimal use of various hemodynamic monitoring modalities keeping in mind the resource-limited settings and the specific needs of our patients. When enough evidence was not forthcoming, we have made recommendations after achieving consensus amongst members. Careful integration of clinical assessment and critical information obtained from laboratory data and monitoring devices should help in improving outcomes of our patients.

How to cite this article

Kulkarni AP, Govil D, Samavedam S, Srinivasan S, Ramasubban S, Venkataraman R, et al. ISCCM Guidelines for Hemodynamic Monitoring in the Critically Ill. Indian J Crit Care Med 2022;26(S2):S66-S76.

Kinetics of capillary refill time after fluid challenge

Background

Capillary refill time (CRT) is a valuable tool for triage and to guide resuscitation. However, little is known about CRT kinetics after fluid infusion.

Methods

We conducted a prospective observational study in a tertiary teaching hospital. First, we analyzed the intra-observer variability of CRT. Next, we monitored fingertip CRT in sepsis patients during volume expansion within the first 24 h of ICU admission. Fingertip CRT was measured every 2 min during 30 min following crystalloid infusion (500 mL over 15 min).

Results

First, the accuracy of repetitive fingertip CRT measurements was evaluated on 40 critically ill patients. Reproducibility was excellent, with an intra-class correlation coefficient of 99.5% (CI 95% [99.3, 99.8]). A CRT variation larger than 0.2 s was considered as significant. Next, variations of CRT during volume expansion were evaluated on 29 septic patients; median SOFA score was 7 [5–9], median SAPS II was 57 [45–72], and ICU mortality rate was 24%. Twenty-three patients were responders as defined by a CRT decrease  > 0.2 s at 30 min after volume expansion, and 6 were non-responders. Among responders, we observed that fingertip CRT quickly improved with a significant decrease at 6–8 min after start of crystalloid infusion, the maximal improvement being observed after 10–12 min (−0.7 [−0.3;−0.9] s) and maintained at 30 min. CRT variations significantly correlated with baseline CRT measurements (R = 0.39, P = 0.05).

Conclusions

CRT quickly improved during volume expansion with a significant decrease 6–8 min after start of fluid infusion and a maximal drop at 10–12 min.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13613-022-01049-x.

Capillary refill time for the management of acute circulatory failure: a survey among pediatric and adult intensivists

INTRODUCTION

Recent studies have shown the prognostic value of capillary refill time (CRT) and suggested that resuscitation management guided by CRT may reduce morbidity and mortality in patients with septic shock. However, little is known about the current use of CRT in routine clinical practice. This study aimed to assess the modalities of CRT use among French adult and pediatric intensivists.

METHODS

A cross-sectional survey exploring CRT practices in acute circulatory failure was performed. The targeted population was French adult and pediatric intensivists (SFAR and GFRUP networks). An individual invitation letter including a survey of 32 questions was emailed twice. Descriptive and analytical statistics were performed.

RESULTS

Among the 6071 physicians who received the letter, 418 (7%) completed the survey. Among all respondents, 82% reported using CRT in routine clinical practice, mainly to diagnose acute circulatory failure, but 45% did not think CRT had any prognostic value. Perfusion goal-directed therapy based on CRT was viewed as likely to improve patient outcome by 37% of respondents. The measurement of CRT was not standardized as the use of a chronometer was rare (3%) and the average of multiple measurements rarely performed (46%). Compared to adult intensivists, pediatric intensivists used CRT more frequently (99% versus 76%) and were more confident in its diagnostic value and its ability to guide treatment.

CONCLUSION

CRT measurement is widely used by intensivists in patients with acute circulatory failure but most often in a non-standardized way. This may lead to a misunderstanding of CRT reliability and clinical usefulness.

Predictors of Requirement of Inotrope Among Patients With Early Sepsis: Special Reference to Microcirculatory Parameters

Introduction

The management of septic shock and refractory septic shock is essential in preventing sepsis-related death. The handheld vital microscope is a new modality of investigation for sepsis for microcirculatory assessment. This study aimed to identify predictors of inotrope requirements among patients with early sepsis and impending septic shock with particular reference to sublingual microcirculation assessment parameters.

Methodology

We conducted an observational cross-sectional hospital-based study in central India. The formal sample size was calculated to be 52 patients using a convenient sampling technique. The study was initiated with ethics approval (IHEC-LOP/2019/ MD0090) with consent from the patients. We used the MicroScan (MicroVision Medical, Netherlands) Video Microscope System (No.16A00102) to obtain sidestream dark-field imaging along with the AVA 4.3C software (MicroVision Medical).

Results

Of 51 cases, 60.8% were women, and 39.2% were men, and the study population had a mean age of 41.0 ± 14.9 years. Patients were recruited from medical wards (64.7%) and emergency departments (35.3%). The most common site of infection was gastrointestinal (33.3%), followed by respiratory infections (25.5%) and genitourinary infections (11.8%). The quick sequential organ failure assessment score was 2.0 ± 0.1. Eight patients required inotropes, and six patients died. High respiratory rates and lactate levels were important predictors of inotrope requirements in patients with early sepsis. Sublingual microcirculatory parameters at baseline did not significantly affect the requirement of inotropes consequently.

Conclusions

Sublingual microscopy is a suggested tool for the management of sepsis. However, without clearly defined cut-off values, handheld vital microscopy could not predict fluid responsiveness among patients with early sepsis. Also, it would be difficult to incorporate this technology into regular practice without equipment upgrades and image acquisition software.

Vitamin C improves microvascular reactivity and peripheral tissue perfusion in septic shock patients

Background

Vitamin C has potential protective effects through antioxidant and anti-inflammatory properties. However, the effect of vitamin C supplementation on microvascular function and peripheral tissue perfusion in human sepsis remains unknown. We aimed to determine vitamin C effect on microvascular endothelial dysfunction and peripheral tissue perfusion in septic shock patients.

Methods

Patients with septic shock were prospectively included after initial resuscitation. Bedside peripheral tissue perfusion and skin microvascular reactivity in response to acetylcholine iontophoresis in the forearm area were measured before and 1 h after intravenous vitamin C supplementation (40 mg/kg). Norepinephrine dose was not modified during the studied period.

Results

We included 30 patients with septic shock. SOFA score was 11 [8–14], SAPS II was 66 [54–79], and in-hospital mortality was 33%. Half of these patients had vitamin C deficiency at inclusion. Vitamin C supplementation strongly improved microvascular reactivity (AUC 2263 [430–4246] vs 5362 [1744–10585] UI, p = 0.0004). In addition, vitamin C supplementation improved mottling score (p = 0.06), finger-tip (p = 0.0003) and knee capillary refill time (3.7 [2.6–5.5] vs 2.9 [1.9–4.7] s, p < 0.0001), as well as and central-to-periphery temperature gradient (6.1 [4.9–7.4] vs 4.6 [3.4–7.0] °C, p < 0.0001). The beneficial effects of vitamin C were observed both in patients with or without vitamin C deficiency.

Conclusion

In septic shock patients being resuscitated, vitamin C supplementation improved peripheral tissue perfusion and microvascular reactivity whatever plasma levels of vitamin C.

ClinicalTrials.gov Identifier: NCT04778605 registered 26 January 2021.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-03891-8.

Capillary refill time in sepsis: A useful and easily accessible tool for evaluating perfusion in children

The international sepsis guidelines emphasize the importance of early identification along with the combined administration of fluids, antibiotics and vasopressors as essential steps in the treatment of septic shock in childhood. However, despite these recommendations, septic shock mortality continues to be very high, especially in countries with limited resources. Cardiovascular involvement is common and, in most cases, determines the outcomes. Early recognition of hemodynamic dysfunction, both in the macro and microcirculation, can help improve outcomes. Capillary refill time (CRT) is a useful, available and easily accessible tool at all levels of care. It is a clinical sign of capillary vasoconstriction due to an excessive sympathetic response which seeks to improve blood redistribution from the micro- to the macrocirculation. An important reason for functionally evaluating the microcirculation is that, in septic shock, the correction of macrocirculation variables is assumed to result in improved tissue perfusion. This has been termed "hemodynamic coherence." However, this coherence often does not occur in advanced stages of the disease. Capillary refill time is useful in guiding fluid resuscitation and identifying more seriously affected sepsis patients. Several factors can affect its measurement, which should preferably be standardized and performed on the upper extremities. In this review, we seek to clarify a few common questions regarding CRT and guide its correct use in patients with sepsis.