Pooled analysis of higher versus lower blood pressure targets for vasopressor therapy septic and vasodilatory shock

Optimal target mean arterial pressure for patients with sepsis-associated encephalopathy: a retrospective cohort study

BACKGROUND

Sepsis-associated encephalopathy (SAE) patients often experience changes in intracranial pressure and impaired cerebral autoregulation. Mean arterial pressure (MAP) plays a crucial role in cerebral perfusion pressure, but its relationship with mortality in SAE patients remains unclear. This study aims to investigate the relationship between MAP and the risk of 28-day and in-hospital mortality in SAE patients, providing clinicians with the optimal MAP target.

METHODS

We retrospectively collected clinical data of patients diagnosed with SAE on the first day of ICU admission from the MIMIC-IV (v2.2) database. Patients were divided into four groups based on MAP quartiles. Kruskal-Wallis H test and Chi-square test were used to compare clinical characteristics among the groups. Restricted cubic spline and segmented Cox regression models, both unadjusted and adjusted for multiple variables, were employed to elucidate the relationship between MAP and the risk of 28-day and in-hospital mortality in SAE patients and to identify the optimal MAP. Subgroup analyses were conducted to assess the stability of the results.

RESULTS

A total of 3,816 SAE patients were included. The Q1 group had higher rates of acute kidney injury and vasoactive drug use on the first day of ICU admission compared to other groups (P < 0.01). The Q1 and Q4 groups had longer ICU and hospital stays (P < 0.01). The 28-day and in-hospital mortality rates were highest in the Q1 group and lowest in the Q3 group. Multivariable adjustment restricted cubic spline curves indicated a nonlinear relationship between MAP and mortality risk (P for nonlinearity < 0.05). The MAP ranges associated with HRs below 1 for 28-day and in-hospital mortality were 74.6-90.2 mmHg and 74.6-89.3 mmHg, respectively.The inflection point for mortality risk, determined by the minimum hazard ratio (HR), was identified at a MAP of 81.5 mmHg. The multivariable adjusted segmented Cox regression models showed that for MAP < 81.5 mmHg, an increase in MAP was associated with a decreased risk of 28-day and in-hospital mortality (P < 0.05). In Model 4, each 5 mmHg increase in MAP was associated with a 15% decrease in 28-day mortality risk (HR: 0.85, 95% CI: 0.79-0.91, p < 0.05) and a 14% decrease in in-hospital mortality risk (HR: 0.86, 95% CI: 0.80-0.93, p < 0.05). However, for MAP ≥ 81.5 mmHg, there was no significant association between MAP and mortality risk (P > 0.05). Subgroup analyses based on age, congestive heart failure, use of vasoactive drugs, and acute kidney injury showed consistent results across different subgroups.Subsequent analysis of SAE patients with septic shock also showed results similar to those of the original cohort.However, for comatose SAE patients (GCS ≤ 8), there was a negative correlation between MAP and the risk of 28-day and in-hospital mortality when MAP was < 81.5 mmHg, but a positive correlation when MAP was ≥ 81.5 mmHg in adjusted models 2 and 4.

CONCLUSION

There is a nonlinear relationship between MAP and the risk of 28-day and in-hospital mortality in SAE patients. The optimal MAP target for SAE patients in clinical practice appears to be 81.5 mmHg.

Hemodynamic goals in sepsis and septic shock resuscitation: An umbrella review of systematic reviews and meta-analyses with trial sequential analysis

OBJECTIVE

The objective of this study was to verify whether any parameter among those used as the target for haemodynamic optimisation (e.g., mean arterial pressure, central venous oxygen saturation, systolic or diastolic dysfunction, CO2 gap, lactates, right ventricular dysfunction, and PvaCO2/CavO2 ratio) is correlated with mortality in an undifferentiated population with sepsis or septic shock.

METHODS

An umbrella review, searching MEDLINE, the Cochrane Database of Systematic Reviews, Health Technology Assessment Database, and the JBI Database of Systematic Reviews and Implementation Reports, was performed. We included systematic reviews and meta-analyses enrolling a population of unselected patients with sepsis or septic shock. The main outcome was mortality. Two authors conducted data extraction and risk-of-bias assessments independently. We used a random-effects model to pool binary and continuous data and summarised estimates of effect using equivalent odds ratios (eORs). We used the ROBIS tool to assess risk of bias and the assessment of multiple systematic reviews 2 score to assess global quality.

DATA SYNTHESIS

17 systematic reviews and meta-analyses (15 828 patients) were included in the quantitative analysis. Diastolic dysfunction (eOR: 1.42; 95% confidence interval [CI]: 1.14-1.76), PvaCO2/CavO2 ratio (eOR: 2.15; 95% CI: 1.37-3.37), and CO2 gap (eOR: 1.86; 95% CI: 1.07-3.25) showed a significant correlation with mortality. Lactates were the parameter with highest inconsistency (I2 = 92%). Central venous oxygen saturation and right ventricle dysfunction showed significant statistical excess test of significance (p-value = 0.009 and 0.005, respectively). None of the considered parameters showed statistically significant publication bias.

CONCLUSIONS

According to this umbrella review, diastolic dysfunction is the haemodynamic variable that is most closely linked to the prognosis of septic patients. The PvaCO2/CavO2 ratio and the CO2gap are significantly related to the mortality of septic patients, but the poor quality of evidence or the low number of cases, studied so far, limit their clinical applicability.

CLINICAL TRIAL REGISTRATION

PROSPERO: International prospective register of systematic reviews, 2023, CRD42023432813 (Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023432813).

Low Versus High Blood Pressure Targets in Critically Ill and Surgical Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

OBJECTIVES

Hypotension is associated with adverse outcomes in critically ill and perioperative patients. However, these assumptions are supported by observational studies. This meta-analysis of randomized controlled trials aims to compare the impact of lower versus higher blood pressure targets on mortality.

DATA SOURCES

We searched PubMed, Cochrane, and Scholar from inception to February 10, 2024.

STUDY SELECTION

Randomized trials comparing lower versus higher blood pressure targets in the management of critically ill and perioperative settings.

DATA EXTRACTION

The primary outcome was all-cause mortality at the longest follow-up available. This review was registered in the Prospective International Register of Systematic Reviews, CRD42023452928.

DATA SYNTHESIS

Of 2940 studies identified by the search string, 28 (12 in critically ill and 16 in perioperative settings) were included totaling 15,672 patients. Patients in the low blood pressure target group had lower mortality (23 studies included: 1019/7679 [13.3%] vs. 1103/7649 [14.4%]; relative risk 0.93; 95% CI, 0.87-0.99; p = 0.03; I2 = 0%). This corresponded to a 97.4% probability of any increase in mortality with a Bayesian approach. These findings were mainly driven by studies performed in the ICU setting and with treatment lasting more than 24 hours; however, the magnitude and direction of the results were similar in the majority of sensitivity analyses including the analysis restricted to low risk of bias studies. We also observed a lower rate of atrial fibrillation and fewer patients requiring transfusion in low-pressure target groups. No differences were found in the other secondary outcomes.

CONCLUSIONS

Based on pooled randomized trial evidence, a lower compared with a higher blood pressure target results in a reduction of mortality, atrial fibrillation, and transfusion requirements. Lower blood pressure targets may be beneficial but there is ongoing uncertainty. However, the present meta-analysis does not confirm previous findings and recommendations. These results might inform future guidelines and promote the study of the concept of protective hemodynamics.

Protocol for a Randomized Controlled Trial to Evaluate a Permissive Blood Pressure Target Versus Usual Care in Critically Ill Children with Hypotension (PRESSURE)

OBJECTIVES

Management of hypotension is a fundamental part of pediatric critical care, with cardiovascular support in the form of fluids or vasoactive drugs offered to every hypotensive child. However, optimal blood pressure (BP) targets are unknown. The PRotocolised Evaluation of PermiSSive BP Targets Versus Usual CaRE (PRESSURE) trial aims to evaluate the clinical and cost-effectiveness of a permissive mean arterial pressure (MAP) target of greater than a fifth centile for age compared with usual care.

DESIGN

Pragmatic, open, multicenter, parallel-group randomized control trial (RCT) with integrated economic evaluation.

SETTING

Eighteen PICUs across the United Kingdom.

PATIENTS

Infants and children older than 37 weeks corrected gestational age to 16 years accepted to a participating PICU, on mechanical ventilation and receiving vasoactive drugs for hypotension.

INTERVENTIONS

Adjustment of hemodynamic support to achieve a permissive MAP target greater than fifth centile for age during invasive mechanical ventilation.

MEASUREMENTS AND MAIN RESULTS

Randomization is 1:1 to a permissive MAP target or usual care, stratified by site and age group. Due to the emergency nature of the treatment, approaching patients for written informed consent will be deferred until after randomization. The primary clinical outcome is a composite of death and days of ventilatory support at 30 days. Baseline demographics and clinical status will be recorded as well as daily measures of BP and organ support, and discharge outcomes. This RCT received Health Research Authority approval (reference 289545), and a favorable ethical opinion from the East of England-Cambridge South Research Ethics Committee on May 10, 2021 (reference number 21/EE/0084). The trial is registered and has an International Standard RCT Number (reference 20609635).

CONCLUSIONS

Trial findings will be disseminated in U.K. national and international conferences and in peer-reviewed journals.

Methylene Blue in Septic Shock: A Systematic Review and Meta-Analysis

OBJECTIVES

Although clinicians may use methylene blue (MB) in refractory septic shock, the effect of MB on patient-important outcomes remains uncertain. We conducted a systematic review and meta-analysis to investigate the benefits and harms of MB administration in patients with septic shock.

DATA SOURCES

We searched six databases (including PubMed, Embase, and Medline) from inception to January 10, 2024.

STUDY SELECTION

We included randomized clinical trials (RCTs) of critically ill adults comparing MB with placebo or usual care without MB administration.

DATA EXTRACTION

Two reviewers performed screening, full-text review, and data extraction. We pooled data using a random-effects model, assessed the risk of bias using the modified Cochrane tool, and used Grading of Recommendations Assessment, Development, and Evaluation to rate certainty of effect estimates.

DATA SYNTHESIS

We included six RCTs (302 patients). Compared with placebo or no MB administration, MB may reduce short-term mortality (RR [risk ratio] 0.66 [95% CI, 0.47-0.94], low certainty) and hospital length of stay (mean difference [MD] -2.1 d [95% CI, -1.4 to -2.8], low certainty). MB may also reduce duration of vasopressors (MD -31.1 hr [95% CI, -16.5 to -45.6], low certainty), and increase mean arterial pressure at 6 hours (MD 10.2 mm Hg [95% CI, 6.1-14.2], low certainty) compared with no MB administration. The effect of MB on serum methemoglobin concentration was uncertain (MD 0.9% [95% CI, -0.2% to 2.0%], very low certainty). We did not find any differences in adverse events.

CONCLUSIONS

Among critically ill adults with septic shock, based on low-certainty evidence, MB may reduce short-term mortality, duration of vasopressors, and hospital length of stay, with no evidence of increased adverse events. Rigorous randomized trials evaluating the efficacy of MB in septic shock are needed.

REGISTRATION

Center for Open Science (https://osf.io/hpy4j).

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.

Development and validation of a nomogram to predict the risk of sepsis-associated encephalopathy for septic patients in PICU: a multicenter retrospective cohort study

BACKGROUND

Patients with sepsis-associated encephalopathy (SAE) have higher mortality rates and longer ICU stays. Predictors of SAE are yet to be identified. We aimed to establish an effective and simple-to-use nomogram for the individual prediction of SAE in patients with sepsis admitted to pediatric intensive care unit (PICU) in order to prevent early onset of SAE.

METHODS

In this retrospective multicenter study, we screened 790 patients with sepsis admitted to the PICU of three hospitals in Shandong, China. Least absolute shrinkage and selection operator regression was used for variable selection and regularization in the training cohort. The selected variables were used to construct a nomogram to predict the risk of SAE in patients with sepsis in the PICU. The nomogram performance was assessed using discrimination and calibration.

RESULTS

From January 2017 to May 2022, 613 patients with sepsis from three centers were eligible for inclusion in the final study. The training cohort consisted of 251 patients, and the two independent validation cohorts consisted of 193 and 169 patients. Overall, 237 (38.7%) patients developed SAE. The morbidity of SAE in patients with sepsis is associated with the respiratory rate, blood urea nitrogen, activated partial thromboplastin time, arterial partial pressure of carbon dioxide, and pediatric critical illness score. We generated a nomogram for the early identification of SAE in the training cohort (area under curve [AUC] 0.82, 95% confidence interval [CI] 0.76-0.88, sensitivity 65.6%, specificity 88.8%) and validation cohort (validation cohort 1: AUC 0.80, 95% CI 0.74-0.86, sensitivity 75.0%, specificity 74.3%; validation cohort 2: AUC 0.81, 95% CI 0.73-0.88, sensitivity 69.1%, specificity 83.3%). Calibration plots for the nomogram showed excellent agreement between SAE probabilities of the observed and predicted values. Decision curve analysis indicated that the nomogram conferred a high net clinical benefit.

CONCLUSIONS

The novel nomogram and online calculator showed performance in predicting the morbidity of SAE in patients with sepsis admitted to the PICU, thereby potentially assisting clinicians in the early detection and intervention of SAE.

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.

Comparison of High-Normal Versus Low-Normal Mean Arterial Pressure at Target on Outcomes in Sepsis or Shock Patients: A Meta-Analysis of Randomized Control Trials

The objective of this meta-analysis was to compare the impact of a high-normal and a low-normal mean arterial pressure (MAP) target on outcomes in patients with sepsis or shock. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines, two investigators conducted a thorough literature search across online databases, including PubMed, Cochrane Library, Web of Science, and EMBASE, spanning from inception to December 10, 2023. The assessed outcomes encompassed all-cause mortality, the need for renal replacement therapy, and the length of intensive care unit (ICU) stay. A total of four randomized controlled trials (RCTs) were included, involving 3507 participants with individual study participant counts ranging from 118 to 2463. The pooled analysis revealed no statistically significant difference in the risk of all-cause mortality between the two groups (Risk Ratio (RR): 0.94, 95% Confidence Interval (CI): 0.87 to 1.01). Furthermore, there was no disparity in the rates of renal replacement therapy and the duration of ICU stay between the high-normal and low-normal MAP groups. Our findings indicate no significant distinctions in mortality, rates of renal replacement therapy, or ICU stay duration between the two groups. However, future trials with larger sample sizes are warranted to comprehensively understand the nuanced effects of different MAP settings on outcomes in patients with sepsis and shock.

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.

Consensus Guidelines for Perioperative Care for Emergency Laparotomy Enhanced Recovery After Surgery (ERAS®) Society Recommendations Part 2-Emergency Laparotomy: Intra- and Postoperative Care

BACKGROUND

This is Part 2 of the first consensus guidelines for optimal care of patients undergoing emergency laparotomy (EL) using an Enhanced Recovery After Surgery (ERAS) approach. This paper addresses intra- and postoperative aspects of care.

METHODS

Experts in aspects of management of high-risk and emergency general surgical patients were invited to contribute by the International ERAS® Society. PubMed, Cochrane, Embase, and Medline database searches were performed for ERAS elements and relevant specific topics. Studies on each item were selected with particular attention to randomized clinical trials, systematic reviews, meta-analyses, and large cohort studies and reviewed and graded using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) system. Recommendations were made on the best level of evidence, or extrapolation from studies on elective patients when appropriate. A modified Delphi method was used to validate final recommendations. Some ERAS® components covered in other guideline papers are outlined only briefly, with the bulk of the text focusing on key areas pertaining specifically to EL.

RESULTS

Twenty-three components of intraoperative and postoperative care were defined. Consensus was reached after three rounds of a modified Delphi Process.

CONCLUSIONS

These guidelines are based on best available evidence for an ERAS® approach to patients undergoing EL. These guidelines are not exhaustive but pull together evidence on important components of care for this high-risk patient population. As much of the evidence is extrapolated from elective surgery or emergency general surgery (not specifically laparotomy), many of the components need further evaluation in future studies.

High-normal versus low-normal mean arterial pressure thresholds in critically ill patients: a systematic review and meta-analysis of randomized trials

PURPOSE

Targeted blood pressure thresholds remain unclear in critically ill patients. Two prior systematic reviews have not shown differences in mortality with a high mean arterial pressure (MAP) threshold, but there have been new studies published since. Thus, we conducted an updated systematic review and meta-analysis of randomized controlled trials (RCTs) that compared the effect of a high-normal vs low-normal MAP on mortality, favourable neurologic outcome, need for renal replacement therapy, and adverse vasopressor-induced events in critically ill patients.

SOURCE

We searched six databases from inception until 1 October 2022 for RCTs of critically ill patients targeted to either a high-normal vs a low-normal MAP threshold for at least 24 hr. We assessed study quality using the revised Cochrane risk-of-bias 2 tool and the risk ratio (RR) was used as the summary measure of association. We used the Grading of Recommendations Assessment, Development, and Evaluation framework to assess the certainty of evidence.

PRINCIPAL FINDINGS

We included eight RCTs with 4,561 patients. Four trials were conducted in patients following out-of-hospital cardiac arrest, two in patients with distributive shock requiring vasopressors, one in patients with septic shock, and one in patients with hepatorenal syndrome. The pooled RRs for mortality (eight RCTs; 4,439 patients) and favourable neurologic outcome (four RCTs; 1,065 patients) were 1.06 (95% confidence interval [CI], 0.99 to 1.14; moderate certainty) and 0.99 (95% CI, 0.90 to 1.08; moderate certainty), respectively. The RR for the need for renal replacement therapy (four RCTs; 4,071 patients) was 0.97 (95% CI, 0.87 to 1.08; moderate certainty). There was no statistical between-study heterogeneity across all outcomes.

CONCLUSION

This updated systematic review and meta-analysis of RCTs found no differences in mortality, favourable neurologic outcome, or the need for renal replacement therapy between critically ill patients assigned to a high-normal vs low-normal MAP target.

STUDY REGISTRATION

PROSPERO (CRD42022307601); registered 28 February 2022.

Higher versus lower blood pressure targets after cardiac arrest: systematic review with individual patient data meta-analysis

PURPOSE

Guidelines recommend targeting mean arterial pressure (MAP) > 65 mmHg in patients after cardiac arrest (CA). Recent trials have studied the effects of targeting a higher MAP as compared to a lower MAP after CA. We performed a systematic review and individual patient data meta-analysis to investigate the effects of higher versus lower MAP targets on patient outcome.

METHOD

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, LILACS, BIOSIS, CINAHL, Scopus, the Web of Science Core Collection, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry, Google Scholar and the Turning Research into Practice database to identify trials randomizing patients to higher (≥ 71 mmHg) or lower (≤70 mmHg) MAP targets after CA and resuscitation. We used the Cochrane Risk of Bias tool, version 2 (RoB 2) to assess for risk of bias. The primary outcomes were 180-day all-cause mortality and poor neurologic recovery defined by a modified Rankin score of 4-6 or a cerebral performance category score of 3-5.

RESULTS

Four eligible clinical trials were identified, randomizing a total of 1,087 patients. All the included trials were assessed as having a low risk for bias. The risk ratio (RR) with 95% confidence interval for 180-day all-cause mortality for a higher versus a lower MAP target was 1.08 (0.92-1.26) and for poor neurologic recovery 1.01 (0.86-1.19). Trial sequential analysis showed that a 25% or higher treatment effect, i.e., RR<0.75, can be excluded. No difference in serious adverse events was found between the higher and lower MAP groups.

CONCLUSIONS

Targeting a higher MAP compared to a lower MAP is unlikely to reduce mortality or improve neurologic recovery after CA. Only a large treatment effect above 25% (RR<0.75) could be excluded, and future studies are needed to investigate if relevant but lower treatment effect exists. Targeting a higher MAP was not associated with any increase in adverse effects.

Evolving Management Practices for Early Sepsis-induced Hypoperfusion: A Narrative Review

Sepsis causes significant morbidity and mortality worldwide. Resuscitation is a cornerstone of management. This review covers five areas of evolving practice in the management of early sepsis-induced hypoperfusion: fluid resuscitation volume, timing of vasopressor initiation, resuscitation targets, route of vasopressor administration, and use of invasive blood pressure monitoring. For each topic, we review the seminal evidence, discuss the evolution of practice over time, and highlight questions for additional research. Intravenous fluids are a core component of early sepsis resuscitation. However, with growing concerns about the harms of fluid, practice is evolving toward smaller-volume resuscitation, which is often paired with earlier vasopressor initiation. Large trials of fluid-restrictive, vasopressor-early strategies are providing more information about the safety and potential benefit of these approaches. Lowering blood pressure targets is a means to prevent fluid overload and reduce exposure to vasopressors; mean arterial pressure targets of 60-65 mm Hg appear to be safe, at least in older patients. With the trend toward earlier vasopressor initiation, the need for central administration of vasopressors has been questioned, and peripheral vasopressor use is increasing, although it is not universally accepted. Similarly, although guidelines suggest the use of invasive blood pressure monitoring with arterial catheters in patients receiving vasopressors, blood pressure cuffs are less invasive and often sufficient. Overall, the management of early sepsis-induced hypoperfusion is evolving toward fluid-sparing and less-invasive strategies. However, many questions remain, and additional data are needed to further optimize our approach to resuscitation.

Association between mean arterial pressure and clinical outcomes among patients with heart failure

AIMS

Mean arterial pressure (MAP) is widely used for evaluating organ perfusion, but its impact on clinical outcomes in patients with heart failure (HF) remains poorly understood. The aim of this study is to investigate the relationship between MAP and all-cause mortality and readmission in patients with HF.

METHODS AND RESULTS

We retrospectively analysed data from PhysioNet, involving 2005 patients with HF admitted to Zigong Fourth People's Hospital between 2016 and 2019. The primary outcomes were composite outcomes of all-cause mortality and readmission at 3 and 6 months. The secondary outcomes were readmission at 3 and 6 months. Multivariate-adjusted Cox regression models, restricted cubic spline curves (RCS), and propensity score matching (PSM) were used to explore the relationship between MAP and clinical outcomes. Among 2005 patients with HF [≥70 years, 1460 (72.8%); male, 843 (42.0%)], the incidence of primary outcome at 3 months was 33.4% (223/668), 24.4% (163/668), and 22.7% (152/669), and at 6 months, it was 47.5% (317/668), 38.5% (257/668), and 38.0% (254/669) across MAP tertiles [from Tertile 1 (T1) to Tertile 3 (T3)], respectively. The RCS showed an 'L-shaped' relationship between MAP and primary or secondary endpoints. Multivariate-adjusted Cox models showed that a higher MAP was significantly associated with a lower risk of composite endpoints at 3 months [adjusted hazard ratio (aHR) 0.75, 95% confidence interval (CI) 0.61-0.92, P = 0.006, Tertile 2 (T2); aHR 0.69, 95% CI 0.56-0.86, P = 0.001, T3] and 6 months (aHR 0.79, 95% CI 0.67-0.93, P = 0.005, T2; aHR 0.77, 95% CI 0.64-0.91, P = 0.003, T3) compared with T1. After 1:1 PSM, the effect of maintaining a relatively higher MAP was slightly attenuated. Threshold analyses indicated that per 10 mmHg increase in MAP, there was a 21% and 14% decrease in composite endpoints at 3 and 6 months, respectively (aHR 0.79, 95% CI 0.69-0.91, P = 0.001), and 6 months (aHR 0.86, 95% CI 0.77-0.97, P = 0.013) in patients with MAP ≤ 93 mmHg. The associations were consistent in readmission (secondary outcomes), various subgroups, and sensitivity analysis.

CONCLUSIONS

A higher MAP was associated with a lower risk of a composite of all-cause mortality and readmission. Maintaining a relatively higher MAP could potentially improve the clinical prognosis for patients with HF.

Clin-STAR corner: Recent practice-changing studies at the interface of pulmonary and critical care medicine and geriatrics

Older adults suffering from chronic pulmonary diseases, such as chronic obstructive pulmonary disease and interstitial lung disease, and critical illnesses, such as sepsis and acute respiratory failure, are more vulnerable to adverse outcomes like disability and greater side effects from treatments. In this update, we discuss recent practice-changing clinical trials and observational studies in Pulmonary & Critical Care Medicine that have advanced our understanding of the diagnosis or management of older adults with chronic lung diseases or critical illnesses.

How We Escalate Vasopressor and Corticosteroid Therapy in Patients With Septic Shock

Septic shock is defined by the need for vasopressor agents to correct hypotension and lactic acidosis resulting from infection, with 30%-40% case fatality rates. The care of patients with worsening septic shock involves multiple treatment decisions involving vasopressor choices and adjunctive treatments. In this edition of "How I Do It", we provide a case-based discussion of common clinical decisions regarding choice of first-line vasopressor, BP targets, route of vasopressor delivery, use of secondary vasopressors, and adjunctive medications. We also consider diagnostic approaches, treatment, and monitoring strategies for the patient with worsening shock, as well as approaches to difficult weaning of vasopressors.

Mean Arterial Pressure Targets and Patient-Important Outcomes in Critically Ill Adults: A Systematic Review and Meta-Analysis of Randomized Trials

OBJECTIVE

To conduct a systematic review and meta-analysis to determine whether targeting a higher mean arterial pressure (MAP) compared with a lower MAP in adults with shock results in differences in patient important outcomes.

DATA SOURCES

We searched MEDLINE, EMBASE, the Cochrane Library, and ClinicalTrials.gov through May 2021.

STUDY SELECTION

Titles and abstracts were screened independently and in duplicate to identify potentially eligible studies, then full text for final eligibility. We included parallel-group randomized controlled trials in adult patients with a diagnosis of shock requiring vasoactive medications. The higher MAP group was required to receive vasoactive medications to target a higher MAP as established by study authors, whereas the lower MAP group received vasoactive medications to target lower MAP.

DATA EXTRACTION

In triplicate, reviewers independently extracted data using a prepiloted abstraction form. Statistical analyses were conducted using the RevMan software Version 5.3.

DATA SYNTHESIS

Six randomized controlled trials (n = 3,690) met eligibility criteria. Targeting a higher MAP (75-85 mm Hg) compared with lower MAP of 65 mm Hg resulted in no difference in mortality (relative risk [RR], 1.06; 95% CI, 0.98-1.15; I2 = 0%; p = 0.12; moderate certainty. Targeting a higher MAP resulted in no difference in the risk of undergoing renal replacement therapy (RR, 0.96; 95% CI, 0.83-1.11; I2 = 24%; p = 0.57; moderate certainty); however, a subgroup analysis comparing patients with and without chronic hypertension demonstrated that a higher MAP may reduce the risk of undergoing renal replacement therapy (RR, 0.83; 95% CI, 0.71-0.98; I2 = 0%; p = 0.02).

CONCLUSIONS

In conclusion, our systematic review and meta-analysis demonstrated with moderate certainty that there is no difference in mortality when a higher MAP is targeted in critically ill adult patients with shock. Further studies are needed to determine the impact of mean arterial pressure on need for renal replacement therapy in this population.

Higher blood pressure versus normotension targets to prevent acute kidney injury: a systematic review and meta-regression of randomized controlled trials

BACKGROUND

Renal hypoperfusion is one of the most common causes of acute kidney injury (AKI), especially in shock and perioperative patients. An optimal blood pressure (BP) target to prevent AKI remains undetermined. We conducted a systematic review and meta-analysis of available randomized clinical trial (RCT) results to address this knowledge gap.

METHODS

From inception to May 13, 2022, we searched Ovid Medline, EMBASE, Cochrane Library, SCOPUS, clinicaltrials.gov, and WHO ICTRP for RCTs comparing higher BP target versus normotension in hemodynamically unstable patients (shock, post-cardiac arrest, or surgery patients). The outcomes of interest were post-intervention AKI rate and renal replacement therapy (RRT) rate. Two investigators independently screened the citations and reviewed the full texts for eligible studies according to a predefined form.

RESULTS

Twelve trials were included, enrolling a total of 5759 participants, with shock, non-cardiac, and cardiac surgery patients accounting for 3282 (57.0%), 1687 (29.3%) and 790 (13.7%) patients, respectively. Compared to lower mean arterial blood pressure (MAP) targets that served as normotension, targeting higher MAP had no significant effect on AKI rates in shock (RR [95% CI] = 1.10 [0.93, 1.29]), in cardiac-surgery (RR [95% CI] = 0.87 [0.73, 1.03]) and non-cardiac surgery patients (RR [95% CI] = 1.25 [0.98, 1.60]) using random-effects meta-analyses. In shock patients with premorbid hypertension, however, targeting MAP above 70 mmHg resulted in significantly lower RRT risks, RR [95%CI] = 1.20 [1.03, 1.41], p < 0.05.

CONCLUSIONS

Targeting a higher MAP in shock or perioperative patients may not be superior to normotension, except in shock patients with premorbid hypertension. Further studies are needed to assess the effects of a high MAP target to preventing AKI in hypertensive patients across common settings of hemodynamic instability. Trial registration This systematic review has been registered on PROSPERO ( CRD42021286203 ) on November 19, 2021, prior to data extraction and analysis.

Septic Shock: Phenotypes and Outcomes

INTRODUCTION

Sepsis is a heterogeneous syndrome that results in life-threatening organ dysfunction. Our goal was to determine the relevant variables and patient phenotypes to use in predicting sepsis outcomes.

METHODS

We performed an ancillary study concerning 119 patients with septic shock at intensive care unit (ICU) admittance (T0). We defined clinical worsening as having an increased sequential organ failure assessment (SOFA) score of ≥ 1, 48 h after admission (ΔSOFA ≥ 1). We performed univariate and multivariate analyses based on the 28-day mortality rate and ΔSOFA ≥ 1 and determined three patient phenotypes: safe, intermediate and unsafe. The persistence of the intermediate and unsafe phenotypes after T0 was defined as a poor outcome.

RESULTS

At T0, the multivariate analysis showed two variables associated with 28-day mortality rate: norepinephrine dose and serum lactate concentration. Regarding ΔSOFA ≥ 1, we identified three variables at T0: norepinephrine dose, lactate concentration and venous-to-arterial carbon dioxide difference (P(v-a)CO₂). At T0, the three phenotypes (safe, intermediate and unsafe) were found in 28 (24%), 70 (59%) and 21 (18%) patients, respectively. We thus suggested using an algorithm featuring norepinephrine dose, lactate concentration and P(v-a)CO₂ to predict patient outcomes and obtained an area under the curve (AUC) of 74% (63-85%).

CONCLUSION

Our findings highlight the fact that identifying relevant variables and phenotypes may help physicians predict patient outcomes.

Use of vasopressors for treatment of vasodilatory hypotension in dogs and cats by Diplomates of the American College of Veterinary Emergency and Critical Care

OBJECTIVE

To identify the most common practices of Diplomates of the American College of Veterinary Emergency and Critical Care (DACVECCs) as they relate to the recognition and treatment of hypotension in dogs and cats, particularly concerning the use of vasopressors in vasodilatory shock states.

DESIGN

A survey regarding vasopressor use was sent to all active DACVECCs using the Veterinary Information Network. Questions focused on respondent characteristics, method of recognition of hypotension, triggers for initiation of vasopressor therapy, first- and second-line vasopressor choice, and methods of determining response to therapy.

SUBJECTS

A total of 734 DACVECCs were invited to participate, and 203 Diplomates (27.7%) completed the survey.

RESULTS

For both dogs and cats, the most common first-line vasopressor was norepinephrine (87.9% in dogs and 83.1% in cats). The most common second-choice vasopressor was vasopressin (44.2% in dogs and 39.0% in cats). Cutoff values for initiating vasopressor therapy varied between species and modality used for blood pressure measurement. In general, most DACVECCs chose to initiate vasopressor therapy at a Doppler blood pressure <90 mm Hg or a mean arterial pressure of <60 or <65 mm Hg when using oscillometric or direct arterial blood pressure measurements in dogs and cats.

CONCLUSIONS

Most DACVECCs adhere to published human guidelines when choosing a first-line vasopressor. However, there is significant variability in blood pressure measurement technique, cutoffs for initiation of vasopressor use, and choice of second-line vasopressors.

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.

Optimal target blood pressure in elderly with septic shock (OPTPRESS) trial: study protocol for a randomized controlled trial

Background

Hemodynamic stabilization is a core component in the resuscitation of septic shock. However, the optimal target blood pressure remains debatable. Previous randomized controlled trials suggested that uniformly adopting a target mean arterial pressure (MAP) higher than 65 mmHg for all adult septic shock patients would not be beneficial; however, it has also been proposed that higher target MAP may be beneficial for elderly patients, especially those with arteriosclerosis.

Methods

A multicenter, pragmatic single-blind randomized controlled trial will be conducted to compare target MAP of 80–85 mmHg (high-target) and 65–70 mmHg (control) in the resuscitation of septic shock patients admitted to 28 hospitals in Japan. Patients with septic shock aged ≥65 years are randomly assigned to the high-target or control groups. The target MAP shall be maintained for 72 h after randomization or until vasopressors are no longer needed to improve patients’ condition. To minimize the adverse effects related to catecholamines, if norepinephrine dose of ≥ 0.1 μg/kg/min is needed to maintain the target MAP, vasopressin will be initiated. Other therapeutic approaches, including fluid administration, hydrocortisone use, and antibiotic choice, will be determined by the physician in charge based on the latest clinical guidelines. The primary outcome is all-cause mortality at 90 days after randomization.

Discussion

The result of this trial will provide great insight on the resuscitation strategy for septic shock in the era of global aged society. Also, it will provide the better understanding on the importance of individualized treatment strategy in hemodynamic management in critically ill patients.

Trial registration

UMIN Clinical Trials Registry; UMIN000041775. Registered 13 September 2020.

Optimal target blood pressure in critically ill adult patients with vasodilatory shock: A systematic review and meta-analysis

While the Surviving Sepsis Campaign guidelines recommend an initial target value of 65 mmHg as the mean arterial pressure (MAP) in patients with septic shock, the optimal MAP target for improving outcomes remains controversial. We performed a meta-analysis to evaluate the optimal MAP for patients with vasodilatory shock, which included three randomized controlled trials that recruited 3,357 patients. Between the lower (60–70 mmHg) and higher (>70 mmHg) MAP target groups, there was no significant difference in all-cause mortality (risk ratio [RR], 1.06; 95% confidence intervals [CI], 0.98–1.16) which was similar in patients with chronic hypertension (RR, 1.10; 95% CI, 0.98–1.24) and patients aged ≥65 years (RR, 1.10; 95% CI, 0.99–1.21). No significant difference in adverse events was observed between the different MAP groups (RR, 1.04; 95% CI, 0.87–1.24); however, supraventricular arrhythmia was significantly higher in the higher MAP group (RR, 1.73; 95% CI, 1.15–2.60). Renal replacement therapy was reduced in the higher MAP group of patients with chronic hypertension (RR, 0.83; 95% CI, 0.71–0.98). Though the higher MAP control did not improve the mortality rate, it may be beneficial in reducing renal replacement therapy in patients with chronic hypertension.

Systematic review registration: UMIN Clinical Trials Registry, identifier UMIN000042624

A Machine-Learning Approach for Estimating Subgroup- and Individual-Level Treatment Effects: An Illustration Using the 65 Trial

Personalizing treatment recommendations or guidelines requires evidence about the heterogeneity of treatment effects (HTE). Machine-learning (ML) approaches can explore HTE by considering many covariates, including complex interactions between them. Causal ML approaches can avoid overfitting, which arises when the same dataset is used to select covariate by treatment interaction terms as to make inferences and reduce reliance on the correct specification of fixed parametric models. We investigate causal forests (CF), a ML method based on modified decision trees that can estimate subgroup- and individual-level treatment effects, without requiring correct prespecification of the effect model. We consider CF alongside parametric approaches for estimating HTE, within the 65 Trial, which evaluates the effect of a permissive hypotension strategy versus usual care on 90-d mortality for critically ill patients aged 65 y or older with vasodilatory hypotension. Here, the CF approach provides similar estimates of treatment effectiveness for prespecified and post hoc subgroups to the parametric approach, and the results of a test for overall HTE show weak evidence of heterogeneity. The CF estimates of individual-level treatment effects, the expected effects of treatment for individuals in subpopulations defined by their covariates, suggest that the permissive hypotension strategy is expected to reduce 90-d mortality for 98.7% of patients but with 95% confidence intervals that include zero for 71.6% of patients. A ML approach is then used to assess the patient characteristics associated with these individual-level effects, and to help target future research that can identify those patient subgroups for whom the intervention is most effective.

Morbidity and mortality in patients managed with high compared with low blood pressure targets during on-pump cardiac surgery: a systematic review and meta-analysis of randomized controlled trials

PURPOSE

Many believe that blood pressure management during cardiac surgery is associated with postoperative outcomes. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to determine the impact of high compared with low intraoperative blood pressure targets on postoperative morbidity and mortality in adults undergoing cardiac surgery on cardiopulmonary bypass (CPB). Our primary objective was to inform the design of a future large RCT.

SOURCE

We searched MEDLINE, EMBASE, Web of Science, CINAHL, and CENTRAL for RCTs comparing high with low intraoperative blood pressure targets in adult patients undergoing any cardiac surgical procedure on CPB. We screened reference lists, grey literature, and conference proceedings.

PRINCIPAL FINDINGS

We included eight RCTs (N =1,116 participants); all examined the effect of blood pressure management only during the CPB. Trial definitions of high compared with low blood pressure varied and, in some, there was a discrepancy between the target and achieved mean arterial pressure. We observed no difference in delirium, cognitive decline, stroke, acute kidney injury, or mortality between high and low blood pressure targets (very-low to low quality evidence). Higher blood pressure targets may have increased the risk of requiring a blood transfusion (three trials; n = 456 participants; relative risk, 1.4; 95% confidence interval, 1.1 to 1.9; P = 0.01; moderate quality evidence) but this finding was based on a small number of trials.

CONCLUSION

Individual trial definitions of high and low blood pressure targets varied, limiting inferences. The effect of high (compared with low) blood pressure targets on other morbidity and mortality after cardiac surgery remains unclear because of limitations with the body of existing evidence. Research to determine the optimal management of blood pressure during cardiac surgery is required.

STUDY REGISTRATION

PROSPERO (CRD42020177376); registered: 5 July 2020.

Associations Between Elevated Systolic Blood Pressure and Outcomes in Critically Ill Patients: A Retrospective Cohort Study and Propensity Analysis

INTRODUCTION

Studies have shown nonlinear relationships between systolic blood pressure (SBP) and outcomes, with increased risk observed at both low and high blood pressure levels. However, the relationships between cumulative times at different SBP levels and outcomes in critically ill patients remain unclear. We hypothesized that an appropriate SBP level is associated with a decrease in adverse outcomes after intensive care unit (ICU) admission.

METHODS

This study was a retrospective analysis of data from the Medical Information Mart for Intensive Care (MIMIC) III database, which includes more than 1,000,000 SBP records from 12,820 patients. Associations of cumulative times at four SBP ranges (<100 mm Hg, 100-120 mm Hg, 120-140 mm Hg, and ≥140 mm Hg) with mortality (12-, 3-, 1-month mortality and in-hospital mortality) were evaluated. Restricted cubic splines and multivariable Cox regression models were employed to assess associations between mortality and cumulative times at SBP levels (4 levels: <2, 2-12, 12-36, and ≥36 h) over 72 h of ICU admission. Additionally, 120 mm Hg to 140 mm Hg was subdivided into <12 h (Group L) and ≥12 h (Group M) subsets and subjected to propensity-score matching and subgroup analyses.

RESULTS

At 120 mm Hg to 140 mm Hg, level-4 SBP was associated with lower adjusted risks of mortality at 12 months (OR, 0.71; CI, 0.61-0.81), 3 months (OR, 0.72; CI, 0.61-0.85), and 1 month (OR, 0.61; CI, 0.48-0.79) and in the hospital (OR, 0.71; CI, 0.58-0.88) than level-1 SBP. The cumulative times at the other 3 SBP ranges (<100 mm Hg, 100-120 mm Hg, and ≥140 mm Hg) were not independent risk predictors of prognosis. Furthermore, Group M had lower 12-month mortality than Group L, which remained in the propensity-score matched and subgroup analyses.

CONCLUSIONS

SBP at 120 mm Hg to 140 mm Hg was associated with decreased adverse outcomes. Randomized trials are required to determine whether the outcomes in critically ill patients improve with early maintenance of a SBP level at 120 mm Hg to 140 mm Hg.

Evidence for the Application of Sepsis Bundles in 2021

Sepsis represents a severe condition that predisposes patients to a high risk of death if its progression is not ended. As with other time-dependent conditions, the performance of determinant interventions has led to significant survival benefits and quality-of-care improvements in acute emergency care. Thus, the initial interventions in sepsis are a cornerstone for prognosis in most patients. Even though the evidence supporting the hour-1 bundle is perfectible, real-life application of thoughtful and organized sepsis care has improved survival and quality of care in settings promoting compliance to evidence-based treatments. Current evidence for implementing the Surviving Sepsis Campaign bundles for early sepsis management is moving forward to better approaches as more substantial evidence evolves.

Hemodynamic Monitoring in Sepsis-A Conceptual Framework of Macro- and Microcirculatory Alterations

Circulatory failure in sepsis is common and places a considerable burden on healthcare systems. It is associated with an increased likelihood of mortality, and timely recognition is a prerequisite to ensure optimum results. While there is consensus that aggressive source control, adequate antimicrobial therapy and hemodynamic management constitute crucial determinants of outcome, discussion remains about the best way to achieve each of these core principles. Sound cardiovascular support rests on tailored fluid resuscitation and vasopressor therapy. To this end, an overarching framework to improve cardiovascular dynamics has been a recurring theme in modern critical care. The object of this review is to examine the nature of one such framework that acknowledges the growing importance of adaptive hemodynamic support combining macro- and microhemodynamic variables to produce adequate tissue perfusion.

Vasopressor-Sparing Strategies in Patients with Shock: A Scoping-Review and an Evidence-Based Strategy Proposition

Despite the abundant literature on vasopressor therapy, few studies have focused on vasopressor-sparing strategies in patients with shock. We performed a scoping-review of the published studies evaluating vasopressor-sparing strategies by analyzing the results from randomized controlled trials conducted in patients with shock, with a focus on vasopressor doses and/or duration reduction. We analyzed 143 studies, mainly performed in septic shock. Our analysis demonstrated that several pharmacological and non-pharmacological strategies are associated with a decrease in the duration of vasopressor therapy. These strategies are as follows: implementing a weaning strategy, vasopressin use, systemic glucocorticoid administration, beta-blockers, and normothermia. On the contrary, early goal directed therapies, including fluid therapy, oral vasopressors, vitamin C, and renal replacement therapy, are not associated with an increase in vasopressor-free days. Based on these results, we proposed an evidence-based vasopressor management strategy.

Acute kidney injury

Acute kidney injury (AKI) is defined by a sudden loss of excretory kidney function. AKI is part of a range of conditions summarized as acute kidney diseases and disorders (AKD), in which slow deterioration of kidney function or persistent kidney dysfunction is associated with an irreversible loss of kidney cells and nephrons, which can lead to chronic kidney disease (CKD). New biomarkers to identify injury before function loss await clinical implementation. AKI and AKD are a global concern. In low-income and middle-income countries, infections and hypovolaemic shock are the predominant causes of AKI. In high-income countries, AKI mostly occurs in elderly patients who are in hospital, and is related to sepsis, drugs or invasive procedures. Infection and trauma-related AKI and AKD are frequent in all regions. The large spectrum of AKI implies diverse pathophysiological mechanisms. AKI management in critical care settings is challenging, including appropriate volume control, nephrotoxic drug management, and the timing and type of kidney support. Fluid and electrolyte management are essential. As AKI can be lethal, kidney replacement therapy is frequently required. AKI has a poor prognosis in critically ill patients. Long-term consequences of AKI and AKD include CKD and cardiovascular morbidity. Thus, prevention and early detection of AKI are essential.

Pulse pressure during the initial resuscitative period in patients with septic shock treated with a protocol-driven resuscitation bundle therapy

BACKGROUND/AIMS

Maintaining a mean arterial pressure (MAP) ≥ 65 mmHg during septic shock should be based on individual circumstances, but specific target is poorly understood. We investigated associations between time-weighted average (TWA) hemodynamic parameters during the initial resuscitative period and 28-day mortality.

METHODS

Prospectively collected data were obtained from a septic shock patient registry, according to the Sepsis-3 definition, between 2016 and 2018. The TWA systolic blood pressure, diastolic blood pressure, MAP, shock index, and pulse pressure (PP) during the first 6 hours after shock recognition were compared. Multivariable regression analysis was performed to assess associations between these parameters and 28-day mortality.

RESULTS

Of 340 patients with septic shock, 92 died. Only the median TWA PP differed between the survivors and non-survivors (39.2 mmHg vs. 43.0 mmHg, p = 0.020), whereas the other indexes did not. When PP was divided into quartiles (< 34, 34 to 40, 40 to 48, and > 48 mmHg), the mortality rate was higher in the highest quartile (41.2%). Multivariable logistic analysis revealed that PP (odds ratio [OR], 1.28; 95% confidence interval [CI], 1.012 to 1.622; p = 0.039) and PP of > 48 mmHg (OR, 2.25; 95% CI, 1.272 to 3.981; p = 0.005) were independently associated with 28-day mortality.

CONCLUSION

PP was significantly associated with 28-day mortality in patients with septic shock and MAP maintained at > 65 mmHg during the first 6 hours. Further studies are warranted to optimize strategies for maintaining PP and MAP at > 65 mmHg during the early resuscitative period.

Staying InformED: Top emergency Medicine pharmacotherapy articles of 2020

The year 2020 was not easy for Emergency Medicine (EM) clinicians with the burden of tackling a pandemic. A large focus, rightfully so, was placed on the evolving diagnosis and management of patients with COVID-19 and, as such, the ability of clinicians to remain up to date on key EM pharmacotherapy literature may have been compromised. This article reviews the most important EM pharmacotherapy publications indexed in 2020. A modified Delphi approach was utilized for selected journals to identify the most impactful EM pharmacotherapy studies. A total of fifteen articles, eleven trials and four meta-analyses, were identified. This review provides a summary of each study, along with a commentary on the impact to the EM literature and EM clinician.

The Surviving Sepsis Campaign: Fluid Resuscitation and Vasopressor Therapy Research Priorities in Adult Patients

OBJECTIVE

Expand upon the priorities of fluid resuscitation and vasopressor therapy research priorities identified by a group of experts assigned by the Society of Critical Care Medicine and the European Society of Intensive Care Medicine.

DATA SOURCES

Original article, literature search.

STUDY SELECTION

Several members of the original task force with expertise specific to the area of fluid resuscitation and vasopressor therapy.

DATA EXTRACTION

None.

DATA SYNTHESIS

None.

CONCLUSION

In the second of a series of manuscripts subsequent to the original article, members with expertise in the subjects expound upon the three identified priorities related to fluid resuscitation and vasopressor therapies. This analysis summarizes what is known and what were identified as ongoing and future research.

Vasopressor Responsiveness Beyond Arterial Pressure: A Conceptual Systematic Review Using Venous Return Physiology

ABSTRACT

We performed a systematic review to investigate the effects of vasopressor-induced hemodynamic changes in adults with shock. We applied a physiological approach using the interacting domains of intravascular volume, heart pump performance, and vascular resistance to structure the interpretation of responses to vasopressors. We hypothesized that incorporating changes in determinants of cardiac output and vascular resistance better reflect the vasopressor responsiveness beyond mean arterial pressure alone.We identified 28 studies including 678 subjects in Pubmed, EMBASE, and CENTRAL databases.All studies demonstrated significant increases in mean arterial pressure (MAP) and systemic vascular resistance during vasopressor infusion. The calculated mean systemic filling pressure analogue increased (16 ± 3.3 mmHg to 18 ± 3.4 mmHg; P = 0.02) by vasopressors with variable effects on central venous pressure and the pump efficiency of the heart leading to heterogenous changes in cardiac output. Changes in the pressure gradient for venous return and cardiac output, scaled by the change in MAP, were positively correlated (r2 = 0.88, P < 0.001). Changes in the mean systemic filling pressure analogue and heart pump efficiency were negatively correlated (r2 = 0.57, P < 0.001) while no correlation was found between changes in MAP and heart pump efficiency.We conclude that hemodynamic changes induced by vasopressor therapy are inadequately represented by the change in MAP alone despite its common use as a clinical endpoint. The more comprehensive analysis applied in this review illustrates how vasopressor administration may be optimized.

Optimal target blood pressure in critically ill adult patients with vasodilatory shock: a protocol for a systematic review and meta-analysis

INTRODUCTION

The optimal target of mean arterial pressure (MAP) for better outcomes in patients with vasodilatory shock remains a matter of debate. Although catecholamines are generally used to maintain target blood pressure in hypotensive patients with vasodilatory shock, the adverse effects of catecholamines must also be considered. We will perform a systematic review and meta-analysis of randomised controlled trials (RCTs) to assess the certainty of evidence determining the optimal target of MAP control for patients with vasodilatory shock in critically ill settings.

METHODS AND ANALYSIS

This study protocol was registered in the University Hospital Medical Information Network Clinical Trials Registry. We will include only RCTs that evaluated the two different comparators for target MAP to be maintained for clinical outcomes of all-cause mortality: organ dysfunction and adverse events in critically ill adult patients with vasodilatory shock. We will search the electronic bibliographic databases of MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials in November 2020. Two reviewers will independently screen titles and abstracts, perform full article reviews and extract study data. We will report study characteristics and assess methodological quality using the Cochrane Risk-of-Bias 2 tool. If pooling is appropriate, we will calculate relative risks with 95% CIs for all outcome measures. Clinical and methodological subgroup and sensitivity analyses will be performed to explore heterogeneity. Overall certainty of evidence will be evaluated using the Grading of Recommendations Assessment, Development and Evaluation approach.

ETHICS AND DISSEMINATION

This study will not involve primary data collection, and formal ethics approval will therefore not be required. We aim to publish this systematic review in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

UMIN000042624.

The surviving sepsis campaign: fluid resuscitation and vasopressor therapy research priorities in adult patients

OBJECTIVE

To expand upon the priorities of fluid resuscitation and vasopressor therapy research priorities identified by a group of experts assigned by the Society of Critical Care Medicine and the European Society of Intensive Care Medicine.

DATA SOURCES

Original paper and literature search.

STUDY SELECTION

Several members of the original task force with expertise specific to the area of fluid resuscitation and vasopressor therapy.

DATA EXTRACTION

None.

DATA SYNTHESIS

None.

CONCLUSION

In the second of a series of manuscripts subsequent to the original paper, members with expertise in the subjects expound upon the three identified priorities related to fluid resuscitation and vasopressor therapies. This analysis summarizes what is known and what were identified as ongoing and future research.

Echocardiographic measure of dynamic arterial elastance predict pressure response during norepinephrine weaning: an observational study

The purpose of this study was to determine whether dynamic elastance E_Adyn derived from echocardiographic measurements of stroke volume variations can predict the success of a one-step decrease of norepinephrine dose. In this prospective single-center study, 39 patients with vasoplegic syndrome treated with norepinephrine and for whom the attending physician had decided to decrease norepinephrine dose and monitored by thermodilution were analyzed. E_Adyn is the ratio of pulse pressure variation to stroke volume variation and was calculated from echocardiography stroke volume variations and from transpulmonary thermodilution. Pulse pressure variation was obtained from invasive arterial monitoring. Responders were defined by a decrease in mean arterial pressure (MAP) > 10% following norepinephrine decrease. The median decrease in norepinephrine was of 0.04 [0.03-0.05] µg kg^-1 min^-1. Twelve patients (31%) were classified as pressure responders with a median decrease in MAP of 13% [12-15%]. E_Adyn was lower in pressure responders (0.40 [0.24-0.57] vs 0.95 [0.77-1.09], p < 0.01). E_Adyn was able to discriminate between pressure responders and non-responders with an area under the curve of 0.86 (CI_95% [0.71 to1.0], p < 0.05). The optimal cut-off was 0.8. E_Adyn calculated from the echocardiographic estimation of the stroke volume variation and the invasive arterial pulse pressure variation can be used to discriminate pressure response to norepinephrine weaning. Agreement between E_Adyn calculated from echocardiography and thermodilution was poor. Echocardiographic E_Adyn might be used at bedside to optimize hemodynamic treatment.

Reduced exposure to vasopressors through permissive hypotension to reduce mortality in critically ill people aged 65 and over: the 65 RCT

BACKGROUND

Vasopressors are administered to critical care patients to avoid hypotension, which is associated with myocardial injury, kidney injury and death. However, they work by causing vasoconstriction, which may reduce blood flow and cause other adverse effects. A mean arterial pressure target typically guides administration. An individual patient data meta-analysis (Lamontagne F, Day AG, Meade MO, Cook DJ, Guyatt GH, Hylands M, et al. Pooled analysis of higher versus lower blood pressure targets for vasopressor therapy septic and vasodilatory shock. Intensive Care Med 2018;44:12-21) suggested that greater exposure, through higher mean arterial pressure targets, may increase risk of death in older patients.

OBJECTIVE

To estimate the clinical effectiveness and cost-effectiveness of reduced vasopressor exposure through permissive hypotension (i.e. a lower mean arterial pressure target of 60-65 mmHg) in older critically ill patients.

DESIGN

A pragmatic, randomised clinical trial with integrated economic evaluation.

SETTING

Sixty-five NHS adult general critical care units.

PARTICIPANTS

Critically ill patients aged ≥ 65 years receiving vasopressors for vasodilatory hypotension.

INTERVENTIONS

Intervention - permissive hypotension (i.e. a mean arterial pressure target of 60-65 mmHg). Control (usual care) - a mean arterial pressure target at the treating clinician's discretion.

MAIN OUTCOME MEASURES

The primary clinical outcome was 90-day all-cause mortality. The primary cost-effectiveness outcome was 90-day incremental net monetary benefit. Secondary outcomes included receipt and duration of advanced respiratory and renal support, mortality at critical care and acute hospital discharge, and questionnaire assessment of cognitive decline and health-related quality of life at 90 days and 1 year.

RESULTS

Of 2600 patients randomised, 2463 (permissive hypotension, n = 1221; usual care, n = 1242) were analysed for the primary clinical outcome. Permissive hypotension resulted in lower exposure to vasopressors than usual care [mean duration 46.0 vs. 55.9 hours, difference -9.9 hours (95% confidence interval -14.3 to -5.5 hours); total noradrenaline-equivalent dose 31.5 mg vs. 44.3 mg, difference -12.8 mg (95% CI -18.0 mg to -17.6 mg)]. By 90 days, 500 (41.0%) patients in the permissive hypotension group and 544 (43.8%) patients in the usual-care group had died (absolute risk difference -2.85%, 95% confidence interval -6.75% to 1.05%; p = 0.154). Adjustment for prespecified baseline variables resulted in an odds ratio for 90-day mortality of 0.82 (95% confidence interval 0.68 to 0.98) favouring permissive hypotension. There were no significant differences in prespecified secondary outcomes or subgroups; however, patients with chronic hypertension showed a mortality difference favourable to permissive hypotension. At 90 days, permissive hypotension showed similar costs to usual care. However, with higher incremental life-years and quality-adjusted life-years in the permissive hypotension group, the incremental net monetary benefit was positive, but with high statistical uncertainty (£378, 95% confidence interval -£1347 to £2103).

LIMITATIONS

The intervention was unblinded, with risk of bias minimised through central allocation concealment and a primary outcome not subject to observer bias. The control group event rate was higher than anticipated.

CONCLUSIONS

In critically ill patients aged ≥ 65 years receiving vasopressors for vasodilatory hypotension, permissive hypotension did not significantly reduce 90-day mortality compared with usual care. The absolute treatment effect on 90-day mortality, based on 95% confidence intervals, was between a 6.8-percentage reduction and a 1.1-percentage increase in mortality.

FUTURE WORK

Future work should (1) update the individual patient data meta-analysis, (2) explore approaches for evaluating heterogeneity of treatment effect and (3) explore 65 trial conduct, including use of deferred consent, to inform future trials.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN10580502.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 14. See the NIHR Journals Library website for further project information.

Comparison of Vasopressor Duration in Septic Shock Patients With and Without Cirrhosis

BACKGROUND

Patients with cirrhosis have immune dysfunction, altered inflammatory response, and hemodynamic changes which increase risk of septic shock and potentially prolong management with fluids, vasopressors, and other therapies. Due to limited available guidance, this study aimed to characterize vasopressor use in patients with cirrhosis in relation to patients without cirrhosis in septic shock.

METHODS

This was a retrospective matched cohort analysis of 122 patients admitted to the intensive care unit (ICU) at an academic medical center from January 2015 to November 2017. Patients were grouped based on the presence or absence of cirrhosis and matched based on severity of illness scoring. The primary outcome was vasopressor duration. Secondary comparisons included total vasopressor requirement, length of hospital and ICU stay, in-hospital mortality, change in organ function, and discharge disposition.

RESULTS

The group with cirrhosis had significantly longer median (interquartile range [IQR]) durations of vasopressor therapy compared with the group without cirrhosis (86.0 [42.0-164.5] vs 39.0 [14.5-82.0] hours; P = 0.003) leading to increased median (IQR) vasopressor exposure (71.7 [15.5-239.5] vs 24.7 [5.3-77.9] mg norepinephrine [NE] equivalents; P = 0.003). No difference was found in in-hospital mortality between groups. However, regression analysis showed vasopressor exposure was associated with in-hospital mortality.

CONCLUSION AND RELEVANCE

Patients with cirrhosis in septic shock have increased vasopressor durations and overall requirements compared with patients without cirrhosis. Increased durations and requirements is associated with poorer outcomes independent of presence of cirrhosis. Future studies are needed to improve vasopressor treatment strategies and end points utilized in cirrhosis.

Evaluating the clinical and cost-effectiveness of permissive hypotension in critically ill patients aged 65 years or over with vasodilatory hypotension: Protocol for the 65 randomised clinical trial

Vasodilatory shock is common in critically ill patients and vasopressors are a mainstay of therapy. A meta-analysis suggested that use of a higher, as opposed to a lower, mean arterial pressure target to guide titration of vasopressor therapy, could be associated with a higher risk of death in older critically ill patients. The 65 trial is a pragmatic, multi-centre, parallel-group, open-label, randomised clinical trial of permissive hypotension (a mean arterial pressure target of 60 -65 mmHg during vasopressor therapy) versus usual care in critically ill patients aged 65 years or over with vasodilatory hypotension. The trial is conducted in 2600 patients from 65 United Kingdom adult, general critical care units. The primary outcome is all-cause mortality at 90 days. An economic evaluation is embedded. The 65 trial received favourable ethical opinion from the South Central - Oxford C Research Ethics Committee and approval from the Health Research Authority. The results will be presented at national and international conferences and published in peer-reviewed medical journals. Trial registration: ISRCTN10580502.

Surgical Infection Society Research Priorities: A Narrative Review of Fourteen Years of Progress

Background: In 2006, the Surgical Infection Society (SIS) utilized a modified Delphi approach to define 15 specific priority research questions that remained unanswered in the field of surgical infections. The aim of the current study was to evaluate the scientific progress achieved during the ensuing period in answering each of the 15 research questions and to determine if additional research in these fields is warranted. Methods: For each of the questions, a literature search using the National Center for Biotechnology Information (NCBI) was performed by the Scientific Studies Committee of the SIS to identify studies that attempted to address each of the defined questions. This literature was analyzed and summarized. The data on each question were evaluated by a surgical infections expert to determine if the question was answered definitively or remains unanswered. Results: All 15 priority research questions were studied in the last 14 years; six questions (40%) were definitively answered and 9 questions (60%) remain unanswered in whole or in part, mainly because of the low quality of the studies available on this topic. Several of the 9 unanswered questions were deemed to remain research priorities in 2020 and warrant further investigation. These included, for example, the role of empiric antimicrobial agents in nosocomial infections, the use of inotropes/vasopressors versus volume loading to raise the mean arterial pressure, and the role of increased antimicrobial dosing and frequency in the obese patient. Conclusions: Several surgical infection-related research questions prioritized in 2006 remain unanswered. Further high-quality research is required to provide a definitive answer to many of these priority knowledge gaps. An updated research agenda by the SIS is warranted at this time to define research priorities for the future.

Optimal VAsopressor TitraTION in patients 65 years and older (OVATION-65): protocol and statistical analysis plan for a randomised clinical trial

INTRODUCTION

Vasodilatory hypotension is common among intensive care unit (ICU) patients; vasopressors are considered standard of care. However, optimal mean arterial pressure (MAP) targets for vasopressor titration are unknown. The objective of the Optimal VAsopressor TitraTION in patients 65 years and older (OVATION-65) trial is to ascertain the effect of permissive hypotension (vasopressor titration to achieve MAP 60-65 mm Hg) versus usual care on biomarkers of organ injury in hypotensive patients aged ≥65 years.

METHODS AND ANALYSIS

OVATION-65 is an allocation-concealed randomised trial in 7 Canadian hospitals. Eligible patients are ≥65 years of age, in an ICU with vasodilatory hypotension, receiving vasopressors for ≤12 hours to maintain MAP ≥65 mm Hg during or after adequate fluid resuscitation, and expected to receive vasopressors for ≥6 additional hours. Patients are excluded for any of the following: active treatment for spinal cord or acute brain injury; vasopressors given solely for bleeding, ventricular failure or postcardiopulmonary bypass vasoplegia; withdrawal of life-sustaining treatments expected within 48 hours; death perceived as imminent; previous enrolment in OVATION-65; organ transplant within the last year; receiving extracorporeal life support or lack of physician equipoise. Patients are randomised to permissive hypotension versus usual care for up to 28 days. The primary outcome is high-sensitivity troponin T, a biomarker of cardiac injury, on day 3. Secondary outcomes include biomarkers of injury to other organs (brain, liver, intestine, skeletal muscle); lactate (a biomarker of global tissue dysoxia); resource utilisation; adverse events; mortality (90 days and 6 months) and cognitive function (6 months). Assessors of biomarkers, mortality and cognitive function are blinded to allocation.

ETHICS AND DISSEMINATION

This protocol has been approved at all sites. Consent is obtained from the eligible patient, the substitute decision-maker if the patient is incapable, or in a deferred fashion where permitted. End-of-grant dissemination plans include presentations, publications and social media platforms and discussion forums.

TRIAL REGISTRATION NUMBER

NCT03431181.

Therapeutic alternatives and strategies for drug conservation in the intensive care unit during times of drug shortage: a report of the Ontario COVID-19 ICU Drug Task Force

During the coronavirus disease (COVID-19) global pandemic, urgent strategies to alleviate shortages are required. Evaluation of the feasibility, practicality, and value of drug conservation strategies and therapeutic alternatives requires a collaborative approach at the provincial level. The Ontario COVID-19 ICU Drug Task Force was directed to create recommendations suggesting drug conservation strategies and therapeutic alternatives for essential drugs at risk of shortage in the intensive care unit during the COVID-19 pandemic. Recommendations were rapidly developed using a modified Delphi method and evaluated on their ease of implementation, feasibility, and supportive evidence. This article describes the recommendations for drug conservation strategies and therapeutic alternatives for drugs at risk of shortage that are commonly used in the care of critically ill patients. Recommendations are identified as preferred and secondary ones that might be less desirable. Although the impetus for generating this document was the COVID-19 pandemic, recommendations should also be applicable for mitigating drug shortages outside of a pandemic. Proposed provincial strategies for drug conservation and therapeutic alternatives may not all be appropriate for every institution. Local implementation will require consultation from end-users and hospital administrators. Competing equipment shortages and available resources should be considered when evaluating the appropriateness of each strategy.

New-Onset Atrial Fibrillation in Sepsis: A Narrative Review

Atrial fibrillation (AF) is a frequently identified arrhythmia during the course of sepsis. The aim of this narrative review is to assess the characteristics of patients with new-onset AF related to sepsis and the risk of stroke and death, to understand if there is a need for anticoagulation. We searched for studies on AF and sepsis on PubMed, the Cochrane database, and Web of Science, and 17 studies were included. The mean incidence of new-onset AF in patients with sepsis was 20.6% (14.7% in retrospective studies and 31.6% in prospective). Risk factors for new-onset AF included advanced age, white race, male sex, obesity, history of cardiopulmonary disease, heart or respiratory failure, and higher disease severity score. In-hospital mortality was higher in patients with than in those without new-onset AF in 10 studies. In four studies the overall intensive care unit and hospital mortality rates were comparable between patients with and without new-onset AF, while three other studies did not provide mortality data. One study reported on the in-hospital incidence of stroke, which was 2.6 versus 0.69% in patients with or without new-onset AF, respectively. Seven of the studies provided follow-up data after discharge. In three studies, new-onset AF was associated with excess mortality at 28 days, 1 year, and 5 years after discharge of 34, 21, and 3% patients, respectively. In two studies, the mortality rate was comparable in patients with and without new-onset AF. Postdischarge stroke was reported in five studies, whereof two studies had no events after 30 and 90 days, one study showed a nonsignificant increase in stroke, and two studies demonstrated a significant increase in risk of stroke after new-onset AF. The absolute risk increase was 0.6 to 1.6%. Large prospective studies are needed to better understand the need for anticoagulation after new-onset AF in sepsis.

Vasopressor Therapy in the Intensive Care Unit

After fluid administration for vasodilatory shock, vasopressors are commonly infused. Causes of vasodilatory shock include septic shock, post-cardiovascular surgery, post-acute myocardial infarction, postsurgery, other causes of an intense systemic inflammatory response, and drug -associated anaphylaxis. Therapeutic vasopressors are hormones that activate receptors-adrenergic: α1, α2, β1, β2; angiotensin II: AG1, AG2; vasopressin: AVPR1a, AVPR1B, AVPR2; dopamine: DA1, DA2. Vasopressor choice and dose vary widely because of patient and physician practice heterogeneity. Vasopressor adverse effects are excessive vasoconstriction causing organ ischemia/infarction, hyperglycemia, hyperlactatemia, tachycardia, and tachyarrhythmias. To date, no randomized controlled trial (RCT) of vasopressors has shown a decreased 28-day mortality rate. There is a need for evidence regarding alternative vasopressors as first-line vasopressors. We emphasize that vasopressors should be administered simultaneously with fluid replacement to prevent and decrease duration of hypotension in shock with vasodilation. Norepinephrine is the first-choice vasopressor in septic and vasodilatory shock. Interventions that decrease norepinephrine dose (vasopressin, angiotensin II) have not decreased 28-day mortality significantly. In patients not responsive to norepinephrine, vasopressin or epinephrine may be added. Angiotensin II may be useful for rapid resuscitation of profoundly hypotensive patients. Inotropic agent(s) (e.g., dobutamine) may be needed if vasopressors decrease ventricular contractility. Dopamine has fallen to almost no-use recommendation because of adverse effects; angiotensin II is available clinically; there are potent vasopressors with scant literature (e.g., methylene blue); and the novel V1a agonist selepressin missed on its pivotal RCT primary outcome. In pediatric septic shock, vasopressors, epinephrine, and norepinephrine are recommended equally because there is no clear evidence that supports the use of one vasoactive agent. Dopamine is recommended when epinephrine or norepinephrine is not available. New strategies include perhaps patients will be started on several vasopressors with complementary mechanisms of action, patients may be selected for particular vasopressors according to predictive biomarkers, and novel vasopressors may emerge with fewer adverse effects.

Consistency of recommendations from clinical practice guidelines for the management of critically ill COVID-19 patients

BACKGROUND

A significant knowledge gap exists for the management of critically ill patients with coronavirus disease 2019 (COVID-19). This study aimed to systematically investigate the consistency of recommendations from the available clinical practice guidelines (CPGs) to those of the WHO on the management of critically ill COVID-19 patients.

METHODS

We examined CPGs and UpToDate point-of-care resources on the management of critically ill COVID-19 patients that had been published as of 30 April 2020 and compared them against the CPG by the WHO. The main outcome was the rate of consistency among CPGs for the management of critically ill COVID-19 patients. Sensitivity analyses were conducted by excluding recommendation statements that were described as insufficient evidence and by excluding single CPGs one at a time.

RESULTS

Thirteen reference recommendations derived from the CPG of the WHO were generated using discrete and unambiguous specifications of the population, intervention, and comparison states. Across CPGs, the rate of consistency in direction with the WHO is 7.7%. When insufficient evidence codings were excluded, the rate of consistency increased substantially to 61.5%. The results of a leave-one-out sensitivity analysis suggested that the UpToDate recommendation source could explain the inconsistency. Consistency in direction rates changed by an absolute 23.1% (from 1/13 (7.7%) to 4/13 (30.8%)) if UpToDate was removed.

CONCLUSIONS

We observed inconsistencies between some recommendations of the CPGs and those of the WHO. These inconsistencies should best be addressed by consensus among the relevant bodies to avoid confusion in clinical practice while awaiting clinical trials to inform us of the best practice.

Acidosis predicts mortality independently from hyperlactatemia in patients with sepsis

RATIONALE AND OBJECTIVES

Acidosis and hyperlactatemia predict outcome in critically ill patients. We assessed BE and pH for risk prediction capabilities in a sub-group of septic patients in the MIMIC-III database.

METHODS

Associations with mortality were assessed by logistic regression analysis in 5586 septic patients. Baseline parameters, lactate concentrations, pH, and BE were analyzed at baseline and after 6 hours.

MEASUREMENTS AND MAIN RESULTS

We combined acidosis (defined as either BE ≤-6 and/or pH ≤7.3) and hyperlactatemia and split the cohort into three subgroups: low-risk (no acidosis and lactate <2.3 mmol/L; n = 2294), medium-risk (either acidosis or lactate >2.3 mmol/L; n = 2125) and high-risk (both acidosis and lactate >2.3 mmol/L; n = 1167). Mortality was 14%, 20% and 38% (p<0.001) in low-risk, medium-risk and high-risk patients, respectively. The predictiveness of this model (AUC 0.63 95%CI 0.61-0.65) was higher compared to acidosis (AUC 0.59 95%CI 0.57-0.61; p<0.001) and lactate >2.3 mmol/L (AUC 0.60 95%CI 0.58-0.62; p<0.001) alone. Hyperlactatemia alone was only moderately predictive for acidosis (AUC 0.60 95%CI 0.59-0.62).

CONCLUSIONS

Acidosis and hyperlactatemia can occur independently to a certain degree. Combining acidosis and hyperlactatemia in a model yielded higher predictiveness for ICU-mortality. Septic patients with acidosis should be treated even more aggressively in the future.