Phenylephrine versus norepinephrine for initial hemodynamic support of patients with septic shock: a randomized, controlled trial

Effects of phenylephrine on systemic and cerebral circulations in humans: a systematic review with mechanistic explanations

We conducted a systematic review of the literature reporting phenylephrine-induced changes in blood pressure, cardiac output, cerebral blood flow and cerebral tissue oxygen saturation as measured by near-infrared spectroscopy in humans. We used the proportion change of the group mean values reported by the original studies in our analysis. Phenylephrine elevates blood pressure whilst concurrently inducing a reduction in cardiac output. Furthermore, despite increasing cerebral blood flow, it decreases cerebral tissue oxygen saturation. The extent of phenylephrine's influence on cardiac output (r = -0.54 and p = 0.09 in awake humans; r = -0.55 and p = 0.007 in anaesthetised humans), cerebral blood flow (r = 0.65 and p = 0.002 in awake humans; r = 0.80 and p = 0.003 in anaesthetised humans) and cerebral tissue oxygen saturation (r = -0.72 and p = 0.03 in awake humans; r = -0.24 and p = 0.48 in anaesthetised humans) appears closely linked to the magnitude of phenylephrine-induced blood pressure changes. When comparing the effects of phenylephrine in awake and anaesthetised humans, we found no evidence of a significant difference in cardiac output, cerebral blood flow or cerebral tissue oxygen saturation. There was also no evidence of a significant difference in effect on systemic and cerebral circulations whether phenylephrine was given by bolus or infusion. We explore the underlying mechanisms driving the phenylephrine-induced cardiac output reduction, cerebral blood flow increase and cerebral tissue oxygen saturation decrease. Individualised treatment approaches, close monitoring and consideration of potential risks and benefits remain vital to the safe and effective use of phenylephrine in acute care.

Noninvasive Cardiac Output Monitoring (NICOM) in the Critically Ill Patient Undergoing Endotracheal Intubation: A Prospective Observational Study

Background: Cardiovascular instability occurring during endotracheal intubation (ETI) in the critically ill is a commonly recognized phenomenon. However, this complication has not been evaluated in terms of the physiological cause (ie, decreased preload, contractility, or afterload) leading to the instability. Thus, the aim of the current investigation was to describe the hemodynamics occurring during ETI with noninvasive physiologic monitoring and to collect preliminary data on the hemodynamic effects of induction agents and positive pressure ventilation. Methods: A multicenter prospective study enrolling adult (≥18 years) critically ill patients undergoing ETI with noninvasive cardiac output monitoring in a medical/surgical intensive care unit from June 2018 to May 2019 was conducted. This study used the Cheetah Medical noninvasive cardiac output monitor to collect hemodynamic data during the peri-intubation period. Additional data collected included baseline characteristics such as illness severity, peri-intubation pharmacologic administration, and mechanical ventilation settings. Results: From the original 27 patients, only 19 (70%) patients had complete data and were included in the final analysis. Propofol was the most common sedative 8 (42%) followed by ketamine 6 (32%) and etomidate 5 (26%). Patients given propofol demonstrated a decrease in total peripheral resistance index (delta change [dynes × s/cm-5/m2]: -2.7 ± 778.2) but stabilization in cardiac index (delta change (L/min/m2]: 0.1 ± 1.5) while etomidate and ketamine demonstrated increases in total peripheral resistance index (etomidate delta change [dynes × s/cm-5/m2]: 302.1 ± 414.3; ketamine delta change [dynes × s/cm-5/m2]: 278.7 ± 418.9) but only etomidate resulted in a decrease in cardiac index (delta change [L/min/m2]: -0.3 ± 0.5). Positive pressure ventilation resulted in minimal changes to hemodynamics during ETI. Conclusions: The current study demonstrates that although propofol administration leads to a decrease in total peripheral resistance index, cardiac index is maintained while etomidate leads to a decrease in cardiac index with both etomidate and ketamine increasing total peripheral resistance index. These hemodynamic profiles are minimally affected by positive pressure ventilation. Study registration: ClinicalTrials.gov ID, NCT03525743.

THE EFFICACY AND SAFETY OF VASOPRESSORS FOR SEPTIC SHOCK PATIENTS: A SYSTEMIC REVIEW AND NETWORK META-ANALYSIS

ABSTRACT

Background: Septic shock is a distributive shock with decreased systemic vascular resistance and MAP. Septic shock contributes to the most common causes of death in the intensive care unit (ICU). Current guidelines recommend the use of norepinephrine as the first-line vasopressor, whereas adrenergic agonists and vasopressin analogs are also commonly used by physicians. To date, very few studies have synthetically compared the effects of multiple types of vasoactive medications. The aim of this study was to systemically evaluate the efficacy of vasoactive agents both individually and in combination to treat septic shock. Methods: The PubMed, MEDLINE, Embase, Web of Science, and Cochrane Central Register for Controlled Trials (CENTRAL) were searched up to May 12, 2022, to identify relevant randomized controlled trials. A network meta-analysis was performed to evaluate the effect of different types of vasopressors. The primary outcome was 28-day all-cause mortality. The secondary outcome was the ICU length of stay. Adverse events are defined as any undesirable outcomes, including myocardial infarction, cardiac arrhythmia, peripheral ischemia, or stroke and cerebrovascular events. Findings: Thirty-three randomized controlled trials comprising 4,966 patients and assessing 8 types of vasoactive treatments were included in the network meta-analysis. The surface under the cumulative ranking curve provided a ranking of vasoactive medications in terms of 28-day all-cause mortality from most effective to least effective: norepinephrine plus dobutamine, epinephrine, vasopressin, terlipressin, norepinephrine, norepinephrine plus vasopressin, dopamine, and dobutamine. Dopamine was associated with a significantly shorter ICU stay than norepinephrine, terlipressin, and vasopressin, whereas other vasoactive medications showed no definite difference in ICU length of stay. Regarding adverse events, norepinephrine was associated with the highest incidences of myocardial infarction and peripheral ischemia. Dopamine was associated with the highest incidence of cardiac arrhythmia. Epinephrine and terlipressin were associated with the highest incidences of myocardial infarction and peripheral ischemia. Interpretation: The results of this network meta-analysis suggest that norepinephrine plus dobutamine is associated with a lower risk of 28-day mortality in septic shock patients than other vasoactive medications, and the use of dopamine is associated with a higher risk of 28-day mortality due to septic shock than norepinephrine, terlipressin, and vasopressin.

Association of the exclusive use of intraoperative phenylephrine for treatment of hypotension with the risk of acute kidney injury after noncardiac surgery

STUDY OBJECTIVE

The hypothesis that the exclusive use of the commonly used vasopressor phenylephrine during the intraoperative period in noncardiac surgery is associated with postoperative acute kidney injury (AKI) was tested.

DESIGN

A retrospective cohort analysis of 16,306 adults undergoing major noncardiac surgery who either did or did not receive phenylephrine was conducted. The primary outcome was the association of the use of phenylephrine with the risk of postoperative AKI defined by the Kidney Disease Improving Global Outcomes (KDIGO) criteria. Logistic regression models with all independently associated potential confounders, and an exploratory model considering only patients with no untreated minutes of hypotension (post-phenylephrine in the exposed cohort, or entire case in the unexposed cohort) were used in the analysis.

SETTING

The study was conducted in a tertiary care university hospital where a total of 8,221 patients were exposed to phenylephrine, and 8,085 were not.

RESULTS

In unadjusted analysis, phenylephrine exposure was associated with an increased risk of AKI (OR 1.615, 95% CI [1.522-1.725], p <  0.001). In an adjusted model including several variables associated with AKI, phenylephrine remained associated with AKI (OR 1.325 [1.153-1.524]), as did post-phenylephrine exposure lengths of hypotension. Exclusion of patients with >1 min of post-phenylephrine exposure hypotension, also demonstrated that phenylephrine use was associated with AKI (OR 1.478, [1.245-1.753]).

CONCLUSIONS

The exclusive use of intraoperative phenylephrine is associated with an increased risk of postoperative renal injury. Anesthesiologists must consider a balanced approach to correct hypotension under anesthesia, including judicious choices for fluids, inotropic support when indicated, and an appropriate adjustment of the plane of anesthesia.

Management of Sepsis and Septic Shock: What Have We Learned in the Last Two Decades?

Sepsis is a clinical syndrome encompassing physiologic and biological abnormalities caused by a dysregulated host response to infection. Sepsis progression into septic shock is associated with a dramatic increase in mortality, hence the importance of early identification and treatment. Over the last two decades, the definition of sepsis has evolved to improve early sepsis recognition and screening, standardize the terms used to describe sepsis and highlight its association with organ dysfunction and higher mortality. The early 2000s witnessed the birth of early goal-directed therapy (EGDT), which showed a dramatic reduction in mortality leading to its wide adoption, and the surviving sepsis campaign (SSC), which has been instrumental in developing and updating sepsis guidelines over the last 20 years. Outside of early fluid resuscitation and antibiotic therapy, sepsis management has transitioned to a less aggressive approach over the last few years, shying away from routine mixed venous oxygen saturation and central venous pressure monitoring and excessive fluids resuscitation, inotropes use, and red blood cell transfusions. Peripheral vasopressor use was deemed safe and is rising, and resuscitation with balanced crystalloids and a restrictive fluid strategy was explored. This review will address some of sepsis management's most important yet controversial components and summarize the available evidence from the last two decades.

Norepinephrine combined with phenylephrine versus norepinephrine in patients with septic shock: a retrospective cohort study

BACKGROUND

Phenylephrine (PE) and norepinephrine (NE) may be used to maintain adequate blood pressure and tissue perfusion in patients with septic shock, but the effect of NE combined with PE (NE-PE) on mortality remains unclear. We hypothesized that NE-PE would not inferior to NE alone for all-cause hospital mortality in patients with septic shock.

METHODS

This single-center, retrospective cohort study included adult patients with septic shock. According to the infusion type, patients were divided into the NE-PE or NE group. Multivariate logistic regression, propensity score matching and doubly robust estimation were used to analyze the differences between groups. The primary outcome was the all-cause hospital mortality rate after NE-PE or NE infusion.

RESULTS

Among 1, 747 included patients, 1, 055 received NE and 692 received NE-PE. For the primary outcome, the hospital mortality rate was higher in patients who received NE-PE than in those who received NE (49.7% vs. 34.5%, p < 0.001), and NE-PE was independently associated with higher hospital mortality (odds ratio = 1.76, 95% confidence interval = 1.36-2.28, p < 0.001). Regarding secondary outcomes, patients in the NE-PE group had longer lengths of stay in ICU and hospitals. Patients in the NE-PE group also received mechanical ventilation for longer durations.

CONCLUSIONS

NE combined with PE was inferior to NE alone in patients with septic shock, and it was associated with a higher hospital mortality rate.

Analysis of Mortality in Patients Treated With Phenylephrine in Septic Shock

BACKGROUND

Phenylephrine is a selective α₁-receptor agonist used to manage shock. Current guidelines for septic shock recommend limited utilization of phenylephrine due to the lack of evidence available. This deviates from previous guidelines, which had recommendations of when utilization may be appropriate.

OBJECTIVE

The primary objective of this study was to evaluate mortality in patients receiving phenylephrine for the management of septic shock.

METHODS

This was a retrospective chart review from September 2015 to September 2017 evaluating all adult patients admitted to an intensive care unit (ICU) on vasopressors for management of septic shock. Patients were divided into 2 groups, those treated with phenylephrine and those treated without phenylephrine. The primary outcome was mortality. Secondary objectives included days on vasopressors and ICU length of stay. Two subgroup analyses were performed: 1 for phenylephrine as first-line therapy and 1 for patients with tachycardia at initiation of vasopressors. Patients started on phenylephrine for salvage therapy were excluded from this study.

RESULTS

499 patients enrolled in the study. 148 (32%) were enrolled in the phenylephrine group. Phenylephrine was associated with an increase in mortality (56% vs 41%; p = 0.003). There was no difference in the days on vasopressors or ICU length of stay. Patients who had ongoing tachycardia were associated with increased mortality with phenylephrine (54% vs 36%, p = 0.02). There was no difference in mortality when phenylephrine was started as the initial vasopressor.

CONCLUSION

Utilization of phenylephrine in septic shock patients, especially those with ongoing tachycardia, was associated with an increased rate of mortality.

Updates in the Management of Perioperative Vasoplegic Syndrome

Vasoplegic syndrome occurs relatively frequently in cardiac surgery, liver transplant, major noncardiac surgery, in post-return of spontaneous circulation situations, and in pateints with sepsis. It is paramount for the anesthesiologist to understand both the pathophysiology of vasoplegia and the different treatment strategies available for rescuing a patient from life-threatening hypotension.

Combination of norepinephrine with phenylephrine versus norepinephrine with vasopressin in critically ill patients with septic shock: A retrospective study

PURPOSE

To evaluate the outcomes of patients with septic shock treated with a combination of norepinephrine with phenylephrine compared to norepinephrine with vasopressin.

MATERIALS AND METHODS

This was a retrospective cohort study including adults admitted between 2002 and 2017 with septic shock according to the Sepsis 3 criteria. We compared outcomes of patients treated with norepinephrine with phenylephrine to those treated with norepinephrine with vasopressin. Multivariate analysis was carried out to evaluate the association of norepinephrine with phenylephrine compared to norepinephrine with vasopressin with in-hospital mortality.

RESULTS

During the study period, 158 patients with septic shock were treated with norepinephrine with phenylephrine and 129 with norepinephrine with vasopressin. Crude in-hospital mortality was not different between the two groups [91/158 (57.6%) versus 80/129 (62.5%), p = 0.40]. There was also no difference in ICU length of stay or hospital length of stay. Multivariate analysis demonstrated no significant association of norepinephrine with phenylephrine with in-hospital mortality compared to norepinephrine with vasopressin (OR 0.62 (95% confidence interval 0.31, 1.23, p = 0.17).

CONCLUSION

Phenylephrine used as a second-line vasoactive agent combined with norepinephrine may be a reasonable option compared to vasopressin. However, this finding needs to be validated in a randomized controlled trial.

Comparison of Heart Rate After Phenylephrine vs Norepinephrine Initiation in Patients With Septic Shock and Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) is a common complication of sepsis. It is unclear whether norepinephrine, an α- and β-agonist, and phenylephrine, an α-agonist, are associated with different heart rates among patients with sepsis and AF.

RESEARCH QUESTION

Among patients with sepsis and AF, what is the difference in heart rate after phenylephrine initiation vs norepinephrine initiation?

STUDY DESIGN AND METHODS

With the use of an extensive database, we identified patients with sepsis and AF at the time of norepinephrine or phenylephrine initiation. We estimated the difference in heart rate between patients who received phenylephrine or norepinephrine 1 and 6 h after vasopressor initiation with the use of multivariable-adjusted linear regression, tested for effect modification by heart rate, and stratified by baseline heart rate ≥ 110 or < 110 beats/min. Secondary outcomes included conversion to sinus rhythm, bradycardia, vasopressor duration, ICU and hospital length of stay, and hospital death. Exploratory analyses were adjusted for practices that occurred after vasopressor initiation; sensitivity analyses used interrupted time series to estimate the difference in average heart rate between patients who received phenylephrine or norepinephrine.

RESULTS

Among 1847 patients with sepsis and AF, 946 patients (51%) received norepinephrine, and 901 patients (49%) received phenylephrine. After multivariable adjustment, phenylephrine was associated with a lower heart rate at 1 h (-4 beats/min; 95% CI, -6 to -1; P < .001) and 6 h (-4 beats/min; 95% CI, -6 to -1; P = .004). Higher heart rate before vasopressor administration was associated with larger heart rate reduction in patients who received phenylephrine compared with norepinephrine. There were no differences in secondary outcomes. Results were similar in exploratory and sensitivity analyses.

INTERPRETATION

In patients with sepsis and AF, the initiation of phenylephrine was associated with modestly lower heart rate compared with norepinephrine. Heart rate at vasopressor initiation appeared to be an important effect modifier. Whether modest reductions in heart rate are associated with clinical outcomes requires further study.

Why Angiotensin II is a Poor Choice for Circulatory Support of Ventilated COVID-19 Patients Compared to Vasopressin

Early in the COVID-19 pandemic when it was first reported that SARS-CoV-2 used membrane-bound angiotensin-converting enzyme-2 (ACE2) as its receptor for entry into cells, warnings were raised against the use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) because of their potential to increase ACE2 expression. These reports ignored the adverse effects that the renin-angiotensin system (RAS) exerts on the cardiovascular system and kidneys via its primary hormone angiotensin (Ang) II acting upon AT₁ receptors that could exacerbate the cytokine storm induced by SARS-CoV-2 ¹. At one point it was even recommended that COVID-19 patients suffering from cardiovascular collapse be administered Ang II to restore blood pressure rather than norepinephrine or vasopressin ². An alternative strategy for treating COVID-19 was the administration of soluble ACE2 (sACE2) to act as a decoy receptor for the virus, misdirecting it away from vulnerable cells expressing membrane bound ACE2 ^3-5. However, a paper published in early 2021 ⁶ described a scenario in which sACE2 and vasopressin played essential roles in SARS-CoV-2 infection of cells vulnerable to the virus. This commentary challenges both the ² and ⁶ reports based upon their misconceptions and technical errors that pose a threat to the administration of life-saving therapies for severely affected COVID-19 patients.

Applicability of Vasopressor Trials in Adult Critical Care: A Prospective Multicentre Meta-Epidemiologic Cohort Study

Objective

To assess the applicability of evidence from landmark randomized controlled trials (RCTs) of vasopressor treatment in critically ill adults.

Study Design and Setting

This prospective, multi-center cohort study was conducted at five medical and surgical intensive care units at three tertiary care centers. Consecutive cases of newly initiated vasopressor treatment were included. The primary end point was the proportion of patients (≥18 years) who met the eligibility criteria of 25 RCTs of vasopressor therapy in critically ill adults included in the most recent Cochrane review. Multilevel Poisson regression was used to estimate the eligibility proportions with 95% confidence intervals for each trial. Secondary end points included the eligibility criteria that contributed most to trial ineligibility, and the relationship between eligibility proportions and (i) the Pragmatic-Explanatory Continuum Indicator Summary-2 (PRECIS-2) score, and (ii) the recruitment-to-screening ratio of each RCT. The PRECIS-2 score was used to assess the degree of pragmatism of each trial.

Results

Between January 1, 2017, and January 1, 2019, a total of 1189 cases of newly initiated vasopressor therapy were included. The median proportion of cases meeting eligibility criteria for all 25 RCTs ranged from 1.3% to 6.0%. The eligibility criteria contributing most to trial ineligibility were the exceedance of a specific norepinephrine dose, the presence of a particular shock type, and the drop below a particular blood pressure value. Eligibility proportions increased with the PRECIS-2 score but not with the recruitment-to-screening ratio of the trials.

Conclusion

The applicability of evidence from available trials on vasopressor treatment in critically ill adults to patients receiving vasopressors in daily practice is limited. Applicability increases with the degree of study pragmatism but is not reflected in a high recruitment-to-screening ratio. Our findings may help researchers design vasopressor trials and promote standardized assessment and reporting of the degree of pragmatism achieved.

SKey Concepts Surrounding Cardiogenic Shock

Cardiogenic shock (CS) is the final common pathway of impaired cardiovascular performance that results in ineffective forward cardiac output producing clinical and biochemical signs of organ hypoperfusion. CS represents the most common cause of shock in the cardiac intensive care unit (CICU) and accounts for a substantial proportion of CICU patient deaths. Despite significant advances in revascularization techniques, pharmacologic therapeutics and mechanical support devices, CS remains associated with a high mortality rate. Indeed, the prevalence of CS within the CICU appears to be increasing. CS can be differentiated as phenotypes reflecting different metabolic, inflammatory, and hemodynamic profiles, depending also on anatomic substrate and congestion profile. Future prospective studies and clinical trials may further characterize these phenotypes and apply targeted intervention for each phenotype and SCAI SHOCK stage rather than a one-size-fits-all approach. Overall, there are 8 key concepts of CS; 1) the mortality associated with CS; 2) Shock attributed to AMI may be declining in both incidence and associated mortality; 3) providers should think about hemodynamic, metabolic, inflammation and cardiac function in totality to assess CS; 4) CS is a dynamic process; 5) no randomized trials evaluating use of the PAC in patients with CS; 6) most data supporting neosynephrine as first line agent in CS; 7) most registries suggest that almost half of CS patients do not have any mechanical support, and the vast majority of the remainder utilize the IABP; and 8) patients with AMI CS should receive emergent PCI of the culprit vessel.

First-line Vasopressor Use in Septic Shock and Route of Administration: An Epidemiologic Study

RATIONALE

Norepinephrine is a first-line agent for treatment of hypotension in septic shock. However, its frequency of use, and potential barriers to its use are unclear.

OBJECTIVES

To evaluate the frequency of use of norepinephrine in septic shock, to identify potential barriers to its use, and to evaluate trends in use of vasopressors over time.

METHODS

Retrospective population-based cohort study of patients with septic shock in Alberta, Canada between July 1, 2012 and December 31, 2018. The primary outcome was receipt of a first-line vasopressor other than norepinephrine ("non-norepinephrine vasopressor"). Predictors of receiving a non-norepinephrine vasopressor were assessed using a multivariable-adjusted, multilevel logistic regression model with intensive care unit (ICU) as a random effect.

RESULTS

Among 6343 patients with septic shock, the proportion of patients receiving non-norepinephrine vasopressors as first-line treatment decreased steadily from 11.5% in 2012 to 3.0% in 2018. Two factors most strongly associated with their receipt were having peripheral intravenous access only (adjusted odds ratio (aOR) 6.15, 95% confidence interval (CI) 4.58-8.26, p<0.001) and year of admission (aOR 0.74 per year after 2012, 95% CI 0.69-0.80, p<0.001). Other factors that had associations after adjustment included admission to a non-teaching hospital (aOR 2.19, 95% CI 1.23-3.89, p=0.007), admission to a coronary care unit (aOR 2.56, 95% CI 1.001-6.54, p=0.05), SOFA score (aOR 0.92 per unit increase, 95% CI 0.88-0.96, p<0.001) and heart rate (aOR 0.92 per 10 beat per minute increase, 95% CI 0.87-0.97, p=0.002).

CONCLUSIONS

In a large cohort of patients in Alberta, Canada, we found a steady decrease in use of first-line vasopressors other than norepinephrine in septic shock. The strongest factor associated with their use was the presence of only peripheral venous access, suggesting this may still be considered a barrier to administration of norepinephrine.

Vasopressors and Risk of Acute Mesenteric Ischemia: A Worldwide Pharmacovigilance Analysis and Comprehensive Literature Review

Vasodilatory shock, such as septic shock, requires personalized management which include adequate fluid therapy and vasopressor treatments. While these potent drugs are numerous, they all aim to counterbalance the vasodilatory effects of a systemic inflammatory response syndrome. Their specific receptors include α- and β-adrenergic receptors, arginine-vasopressin receptors, angiotensin II receptors and dopamine receptors. Consequently, these may be associated with severe adverse effects, including acute mesenteric ischemia (AMI). As the risk of AMI depends on drug class, we aimed to review the evidence of plausible associations by performing a worldwide pharmacovigilance analysis based on the World Health Organization database, VigiBase®. Among 24 million reports, 104 AMI events were reported, and disproportionality analyses yielded significant association with all vasopressors, to the exception of selepressin. Furthermore, in a comprehensive literature review, we detailed mechanistic phenomena which may enhance vasopressor selection, in the course of treating vasodilatory shock.

Mitigation of dexamethasone-induced nephrotoxicity by modulating the activity of adrenergic receptors: Implication of Wnt/β-arrestin2/β-catenin pathway

The present study aimed to investigate the role of α and β-adrenergic receptors (βARs) in mediation or modulation of the dexamethasone-induced nephrotoxicity by using different pharmacological interventions. Nephrotoxicity was induced by subcutaneous injection of dexamethasone (10 mg/kg) for 7 days in Wistar albino rats. Eight groups were used: control; dexamethasone; carvedilol; phenylephrine; carvedilol and phenylephrine; propranolol; doxazosin; propranolol and doxazosin. At the end of experiment, rats were euthanized and blood, urine and kidney samples were collected. Serum and urinary creatinine and urinary total protein levels were measured. Also, the renal tissue levels of diacylglycerol (DAG); Akt kinase activity, malondialdehyde (MDA), NADPH oxidase 2 (NOX2), transforming growth factor-β (TGF-β), Wnt3A and β-catenin were recorded. Furthermore, histopathological and β-arrestin2-immunohistochemical examinations of renal tissues were performed. Results: Dexamethasone induced glomerular damage, proteinuria, renal oxidative stress and upregulated the renal Wnt/β-arrestin2/β-catenin pathway and the profibrotic signals. Blocking the α1 and βARs by carvedilol reduced the dexamethasone-induced nephrotoxicity. Pre-injection of phenylephrine did not reduce the reno-protective action of carvedilol. Blocking the βARs only by propranolol reduced the dexamethasone-induced nephrotoxicity to the same extent of carvedilol group. Blocking the α1ARs only by doxazosin reduced dexamethasone-induced nephrotoxicity to a higher extent than other treatments. However, combined use of propranolol and doxazosin did not synergize the reno-protective effects of doxazosin. Conclusion: Dexamethasone induces nephrotoxicity, possibly, by upregulating the Wnt/β-arrestin2/β-catenin pathway. Blocking either α1ARs or βARs can effectively protect against the dexamethasone-induced nephrotoxicity. However, combined blocking of α1ARs and βARs does not synergize the reno-protective effects.

Recent advances in the pharmacological management of sepsis-associated acute kidney injury

INTRODUCTION

Acute kidney injury is a common occurrence in patients with sepsis and portends a high mortality as well as increased morbidity with numerous sequelae including the development of chronic kidney disease. Currently, there are no specific therapies that either prevent AKI or hasten its recovery. Thus, clinicians typically rely on management of the underlying infection, optimization of hemodynamic parameters as well as avoidance of nephrotoxins to maximize outcomes.

AREAS COVERED

Recent advances in understanding the mechanisms of sepsis as well as how these pathways may interact to lead to acute kidney injury have opened the door to the development of new, targeted therapies. This review focuses on the operative pathways in sepsis that have been identified as critical in leading to acute kidney injury and associated therapeutic agents that target these pathways.

EXPERT OPINION

Despite increased understanding of the pathogenesis of sepsis, development of effective therapeutics to decrease the incidence of AKI have lagged. This is likely due to the complex pathophysiology with overlapping pathways and need for multiple therapies guided by specific biomarkers. Biomarkers that detail operative pathways may be able to guide the institution of more specific therapies with the hope for improved outcomes.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members.As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.

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 in the critically ill: an updated review on pathophysiology and management

Acute kidney injury (AKI) is now recognized as a heterogeneous syndrome that not only affects acute morbidity and mortality, but also a patient’s long-term prognosis. In this narrative review, an update on various aspects of AKI in critically ill patients will be provided. Focus will be on prediction and early detection of AKI (e.g., the role of biomarkers to identify high-risk patients and the use of machine learning to predict AKI), aspects of pathophysiology and progress in the recognition of different phenotypes of AKI, as well as an update on nephrotoxicity and organ cross-talk. In addition, prevention of AKI (focusing on fluid management, kidney perfusion pressure, and the choice of vasopressor) and supportive treatment of AKI is discussed. Finally, post-AKI risk of long-term sequelae including incident or progression of chronic kidney disease, cardiovascular events and mortality, will be addressed.

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.

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.

Norepinephrine in Septic Shock: A Systematic Review and Meta-analysis

Introduction

Most experts recommend norepinephrine as the first-line agent in septic shock. Our objective was to determine the effectiveness and safety of norepinephrine in patients with septic shock.

Methods

We searched the Cochrane Central Register of Controlled Trials and Epistemonikos, as well as MEDLINE from 1966 till August 2019. Screening of full texts, evaluation for eligibility, and data extraction were done by four independent reviewers. We estimated risk ratios (RR) and mean differences (MD) using a random-effects model with 95% confidence intervals (CI). The primary outcomes included the number of participants who achieved the target mean arterial pressure (MAP), time to achieve the target MAP, and number of participants with all-cause 28-day mortality. The secondary outcomes included the length of stay in the intensive care unit, length of hospital stay, incidence of arrhythmia and myocardial infarction, vasopressor-free days, and number of participants with all-cause 90-day mortality.

Results

We identified 11 randomized controlled trials with a total of 4,803 participants. There was no difference in the number of participants who achieved the target MAP between those patients receiving norepinephrine and other vasopressors (RR 1.44; 95% CI, 0.32 to 6.54; P = 0.640; I² = 94%; two trials, 116 participants). There was no significant difference in time to achieve the target MAP (MD −0.05; 95%, CI, −0.32 to 0.21; P = 0.690; I² = 26%; two trials, 1763 participants) and all-cause 28-day mortality (RR 0.95; 95% CI, 0.89 to 1.02; P = 0.160; I² = 0%; seven trials, 4,139 participants). Regarding the secondary outcome, norepinephrine may significantly reduce the incidence of arrhythmia as compared to other vasopressors (RR 0.64; 95% CI, 0.42 to 0.97; P = 0.030; I² = 64%; six trials, 3974 participants). There was no difference in the incidence of myocardial infarction (RR 1.28; 95% CI, 0.79 to 2.09), vasopressor-free day (RR 0.46; 95% CI, −1.82 to 2.74) and all-cause 90-day mortality (RR 1.08; 95% CI, 0.96 to 1.21) between norepinephrine and vasopressors.

Conclusion

In minimizing the occurrence of an arrhythmia, norepinephrine is superior to other vasopressors, making it safe to be used in septic shock. However, there was insufficient evidence concerning mortality and achievement of the target MAP outcomes.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020)

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2020 (J-SSCG 2020), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created as revised from J-SSCG 2016 jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in September 2020 and published in February 2021. An English-language version of these guidelines was created based on the contents of the original Japanese-language version. The purpose of this guideline is to assist medical staff in making appropriate decisions to improve the prognosis of patients undergoing treatment for sepsis and septic shock. We aimed to provide high-quality guidelines that are easy to use and understand for specialists, general clinicians, and multidisciplinary medical professionals. J-SSCG 2016 took up new subjects that were not present in SSCG 2016 (e.g., ICU-acquired weakness [ICU-AW], post-intensive care syndrome [PICS], and body temperature management). The J-SSCG 2020 covered a total of 22 areas with four additional new areas (patient- and family-centered care, sepsis treatment system, neuro-intensive treatment, and stress ulcers). A total of 118 important clinical issues (clinical questions, CQs) were extracted regardless of the presence or absence of evidence. These CQs also include those that have been given particular focus within Japan. This is a large-scale guideline covering multiple fields; thus, in addition to the 25 committee members, we had the participation and support of a total of 226 members who are professionals (physicians, nurses, physiotherapists, clinical engineers, and pharmacists) and medical workers with a history of sepsis or critical illness. The GRADE method was adopted for making recommendations, and the modified Delphi method was used to determine recommendations by voting from all committee members. As a result, 79 GRADE-based recommendations, 5 Good Practice Statements (GPS), 18 expert consensuses, 27 answers to background questions (BQs), and summaries of definitions and diagnosis of sepsis were created as responses to 118 CQs. We also incorporated visual information for each CQ according to the time course of treatment, and we will also distribute this as an app. The J-SSCG 2020 is expected to be widely used as a useful bedside guideline in the field of sepsis treatment both in Japan and overseas involving multiple disciplines.

ATS Core Curriculum 2020. Adult Critical Care Medicine

The American Thoracic Society Core Curriculum updates clinicians annually in adult and pediatric pulmonary disease, medical critical care, and sleep medicine, in a 3- to 4-year recurring cycle of topics. These topics will be presented at the 2020 International Conference. Below is the adult critical care medicine core including complications of chemotherapy, acute-on-chronic liver failure, alcohol withdrawal syndrome, mechanical circulatory support, direct oral anticoagulants, upper gastrointestinal hemorrhage, and vasopressor selection.

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.

Vasopressor Therapy and Blood Pressure Management in the Setting of Acute Kidney Injury

Acute kidney injury (AKI) is common in the setting of shock. Hemodynamic instability is a risk factor for the development of AKI, and pathophysiological mechanisms include loss of renal perfusion pressure and impaired microcirculation. Although restoration of mean arterial pressure (MAP) may mitigate the risk of AKI to some extent, evidence on this is conflicting. Also debatable is the optimal blood pressure needed to minimize the risk of kidney injury. A MAP of 65 mm Hg traditionally has been considered adequate to maintain renal perfusion pressure, and studies have failed to consistently show improved outcomes at higher levels of MAP. Therapeutic options to support renal perfusion consist of catecholamines, vasopressin, and angiotensin II. Although catecholamines are the most studied, they are associated with adverse events at higher doses, including AKI. Vasopressin and angiotensin II are noncatecholamine options to support blood pressure and may improve microcirculatory hemodynamics through unique mechanisms, including differential vasoconstriction of efferent and afferent arterioles within the nephron. Future areas of study include methods by which clinicians can measure renal blood flow in a macrocirculatory and microcirculatory way, a personalized approach to blood pressure management in septic shock using patient-specific measures of perfusion adequacy, and novel agents that may improve the microcirculation within the kidneys without causing adverse microcirculatory effects in other organs.

Vasopressor and Inotrope Therapy in Cardiac Critical Care

Patients admitted to the cardiac intensive care unit (CICU) are often in shock and require hemodynamic support. Identifying and addressing the pathophysiology mechanisms operating in an individual patient is crucial to achieving a successful outcome, while initiating circulatory support therapy to restore adequate tissue perfusion. Vasopressors and inotropes are the cornerstone of supportive medical therapy for shock, in addition to fluid resuscitation when indicated. Timely initiation of optimal vasopressor and inotrope therapy is essential for patients with shock, with the ultimate goals of restoring effective tissue perfusion in order to normalize cellular metabolism. Use of vasoactive agents for hemodynamic support of patients with shock should take both arterial pressure and tissue perfusion into account when choosing therapeutic interventions. For most patients with shock, including cardiogenic or septic shock, norepinephrine (NE) is an appropriate choice as a first-line vasopressor titrated to achieve an adequate arterial pressure due to a lower risk of adverse events than other catecholamine vasopressors. If tissue and organ perfusion remain inadequate, an inotrope such as dobutamine may be added to increase cardiac output to a sufficient level that meets tissue demand. Low doses of epinephrine or dopamine may be used for inotropic support, but high doses of these drugs carry an excessive risk of adverse events when used for vasopressor support and should be avoided. When NE alone is inadequate to achieve an adequate arterial pressure, addition of a noncatecholamine vasopressor such as vasopressin or angiotensin-II is reasonable, in addition to rescue therapies that may improve vasopressor responsiveness. In this review, we discuss the pharmacology and evidence-based use of vasopressor and inotrope drugs in critically ill patients, with a focus on the CICU population.

Angiotensin II for the emergency physician

Refractory hypotension is one of the most common and difficult clinical problems faced by acute care clinicians, and it poses a particularly large problem to the emergency physician when a patient in undifferentiated shock arrives in the department. Angiotensin II (Ang-2) has been previously used as a vasopressor to combat shock; the feasibility of its clinical use has been reinvigorated after approval of a human synthetic formulation of the medication by the US Food and Drug Administration in 2017 and the European Medicines Agency in 2019. A thorough literature search was completed, and in this review, we discuss the discovery and development of Ang-2, its complex mechanisms of vasoconstriction, its potential adverse effects and its potential role in clinical practice for emergency physicians.

Does Switching Norepinephrine to Phenylephrine in Septic Shock Complicated by Atrial Fibrillation With Rapid Ventricular Response Improve Time to Rate Control?

BACKGROUND

Atrial fibrillation (AF) frequently develops during critical illness. In septic shock complicated by rapid AF, the use of phenylephrine may be advantageous secondary to its β-1 sparing properties. However, evidence supporting this strategy is lacking.

OBJECTIVE

The purpose of this study is to determine the clinical effect on rate control of transitioning norepinephrine to phenylephrine in septic shock patients who develop AF with a rapid ventricular response (RVR).

METHODS

A single-center retrospective study of septic shock patients admitted to the medical or surgical intensive care unit (ICU) who developed AF with RVR (heart rate >110 beats per minute [bpm]). Patients who were switched to phenylephrine were compared to those who remained on norepinephrine. The primary end point was sustained achievement of rate control. A time-varying Cox proportional hazards model was used to assess the primary end point.

RESULTS

A total of 67 patients were included in the study, of which 28 were switched to phenylephrine. Baseline characteristics were similar between groups. The unadjusted hazard ratio for achieving rate control was significant at 1.99 (95% confidence interval [CI]: 1.19-3.34; P < .01) for the phenylephrine group. The adjusted hazard ratio was 1.75 (95% CI: 0.86-3.53; P = .12). There were no statistically significant differences in mortality or ICU length of stay.

CONCLUSION

Our study suggests a potential clinical effect on achieving rate control when switching to phenylephrine cannot be excluded. It remains unclear if there is a benefit on mortality or length of stay outcomes in critically ill patients.

Combination era, using combined vasopressors showed benefits in treating septic shock patients: a network meta-analysis of randomized controlled trials

Background

Septic shock is one of the major healthcare problems, affecting millions of people around the world every year. The object of this study is to find the best kind of regimen of vasopressors treatment in septic shock.

Methods

The PubMed, and the Web of Science were used to find the included studies. Stata 15.1 was performed to this systemic review and network meta-analysis.

Results

After searching and screening the articles, finally we included articles about 31 randomized controlled trials (RCTs), 11 arms (dopamine, dopexamine, epinephrine, norepinephrine, norepinephrine + dobutamine, norepinephrine + dopexamine, norepinephrine + epinephrine, norepinephrine + vasopressin, phenylephrine, terlipressin, vasopressin) and total 5,928 patients with septic shock. Compared with dopamine, the regimens (epinephrine, norepinephrine, norepinephrine + dobutamine, and vasopressin) have significantly lower 28-day mortality. Ranking the regimens in the order of estimated probabilities of each treatment by using the network meta-analysis for 28-day mortality, the result showed that norepinephrine + dopexamine was the best one (57.3%), followed by norepinephrine + epinephrine (14.8%), norepinephrine + dobutamine (10.9%), dopexamine (11.2%), terlipressin (9.8%), norepinephrine + vasopressin (2.4%), phenylephrine (1.2%), epinephrine (1.0%), vasopressin (0.5%), norepinephrine (0.0%), and dopamine (0.0%). In addition, for the results of arrhythmia and increased heart rate, the combination regimens groups did not showed inferiority to other single regimen groups.

Conclusions

Single dopamine had significantly higher 28d mortality. Combination regimens of vasopressors accounted for the best three therapeutic regimens. In treating patients with septic shock, using combining regimens probably gets more benefits.

Vasopressor Infusion During Prone Spine Surgery and Acute Renal Injury: A Retrospective Cohort Analysis

BACKGROUND

Hypotension is associated with acute kidney injury, but vasopressors used to treat hypotension may also compromise renal function. We therefore tested the hypothesis that vasopressor infusion during complex spine surgery is not associated with impaired renal function.

METHODS

In this retrospective cohort analysis, we considered adults who had complex spine surgery between January 2005 and September 2014 at the Cleveland Clinic Main Campus. Our primary outcome was postoperative estimated glomerular filtration rate. Secondarily, we evaluated renal function using Acute Kidney Injury Network criteria. We obtained data for 1814 surgeries, including 689 patients (38%) who were given intraoperative vasopressors infusion for ≥30 minutes and 1125 patients (62%) who were not. Five hundred forty patients with and 540 patients without vasopressor infusions were well matched across 32 potential confounding variables.

RESULTS

In matched patients, vasopressor infusions lasted an average of 173 ± 100 minutes (SD) and were given a median dose (1st quintile, 3rd quintile) of 3.4-mg (1.5, 6.7 mg) phenylephrine equivalents. Mean arterial pressure and the amounts of hypotension were similar in each matched group. The postoperative difference in mean estimated glomerular filtration rate in patients with and without vasopressor infusions was only 0.8 mL/min/1.73 m (95% CI, -0.6 to 2.2 mL/min/1.73 m) (P = .28). Intraoperative vasopressor infusion was also not associated with increased odds of augmented acute kidney injury stage.

CONCLUSIONS

Clinicians should not avoid typical perioperative doses of vasopressors for fear of promoting kidney injury. Tolerating hypotension to avoid vasopressor use would probably be a poor strategy.

Comparative efficacy of vasoactive medications in patients with septic shock: a network meta-analysis of randomized controlled trials

Background

Catecholamines, especially norepinephrine, are the most frequently used vasopressors for treating patients with septic shock. During the recent decades, terlipressin, vasopressin V1A agonist, and even Ca²⁺ sensitizer were increasingly used by physicians. The aim of this study is to compare the efficacy of such different kinds of vasoactive medications on mortality among patients with septic shock.

Methods

Relevant randomized controlled trials were identified by searching PubMed, Embase, Web of Science, and the Cochrane Central Register of Controlled Trials updated to February 22, 2018. A network meta-analysis was performed to evaluate the effect of different types of vasoactive medications. The primary outcome was 28-day mortality. Intensive care unit (ICU) mortality, hospital and ICU length of stay (LOS), and adverse events were also assessed.

Results

A total of 43 trials with 5767 patients assessing 17 treatment modalities were included. Treatments ranking based on surface under the cumulative ranking curve values from largest to smallest were NE/DB 85.9%, TP 75.1%, NE/EP 74.6%, PI 74.1%, EP 72.5%, VP 66.1%, NE 59.8%, PE 53.0%, DA 42.1%, DX 38.2%, SP 27.0%, PA 24.3%, EX 22.8%, LE 21.5%, and DB 13.3% for 28-day mortality. Treatments ranking for ICU mortality were TP/NE 86.4%, TP 80.3%, TP/DB/NE 65.7%, VP/NE 62.8%, NE 57.4%, VP 56.5%, PE 48.4%, DA 33.0%, PA 27.5%, LE 22.1%, and DB 9.9%. The incidence of myocardial infarction was reported with NE/EP 3.33% (n = 1 of 30), followed by EP 3.11% (n = 5 of 161), and then VP 3.10% (n = 19 of 613), NE 3.03% (n = 43 of 1417), DA 2.21% (n = 19 of 858), NE/DB 2.01% (n = 4 of 199), LE 1.16% (n = 3 of 258), and PA 0.39% (n = 1 of 257). The incidence of arrhythmia was reported with DA 26.01% (n = 258 of 992), followed by EP 22.98% (n = 37 of 161), and then NE/DB 20.60% (n = 41 of 199), NE/EP 20.0% (n = 6 of 30), NE 8.33% (n = 127 of 1525), LE 5.81% (n = 15 of 258), PA 2.33% (n = 6 of 257), and VP 1.67% (n = 10 of 600).

Conclusions

The use of norepinephrine plus dobutamine was associated with lower 28-day mortality for septic shock, especially among patients with lower cardiac output.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2427-4) contains supplementary material, which is available to authorized users.

Midodrine as an Adjuvant to Intravenous Vasopressor Agents in Adults With Resolving Shock: Systematic Review and Meta-Analysis

PURPOSE

To evaluate the effects of midodrine in addition to intravenous vasopressor therapy on outcomes in adults recovering from shock.

MATERIALS AND METHODS

PubMed, Scopus, Clinicaltrials.gov, and published abstracts were searched from inception to November 2018 for studies comparing outcomes in shock after midodrine initiation versus no midodrine.

RESULTS

Three studies with 2533 patients were included. Patients in whom midodrine was added to intravenous vasopressor therapy compared to intravenous vasopressor therapy alone experienced similar intensive care unit (ICU; mean difference [MD]: 1.38 days, 95% confidence interval [CI]: -3.48 to 6.23, I² = 93%) and hospital lengths of stay (MD: 4.37 days, 95% CI: -3.45 to 12.19, I² = 93%) and intravenous vasopressor duration after midodrine initiation (MD: 7.28 days, 95% CI: -0.86 to 15.41, I² = 97%). Mortality was similar between groups (odds ratio: 0.74, 95% CI: 0.44-1.27, I² = 65%). Qualitative assessment of reporting biases revealed minimal location bias, moderate selective outcome reporting bias, no selective analysis reporting bias, and no conflict of interest bias.

CONCLUSIONS

Midodrine had no effect on ICU or hospital length of stay. These results were highly susceptible to the study heterogeneity and availability. Future investigation into standardized initiation of midodrine at an adequate dosage with an expedited titration strategy is needed in order to assess the utility of this strategy in shock management.

Shock - Classification and Pathophysiological Principles of Therapeutics

The management of patients with shock is extremely challenging because of the myriad of possible clinical presentations in cardiogenic shock, septic shock and hypovolemic shock and the limitations of contemporary therapeutic options. The treatment of shock includes the administration of endogenous catecholamines (epinephrine, norepinephrine, and dopamine) as well as various vasopressor agents that have shown efficacy in the treatment of the various types of shock. In addition to the endogenous catecholamines, dobutamine, isoproterenol, phenylephrine, and milrinone have served as the mainstays of shock therapy for several decades. Recently, experimental studies have suggested that newer agents such as vasopressin, selepressin, calcium-sensitizing agents like levosimendan, cardiac-specific myosin activators like omecamtiv mecarbil (OM), istaroxime, and natriuretic peptides like nesiritide can enhance shock therapy, especially when shock presents a more complex clinical picture than normal. However, their ability to improve clinical outcomes remains to be proven. It is the purpose of this review to describe the mechanism of action, dosage requirements, advantages and disadvantages, and specific indications and contraindications for the use of each of these catecholamines and vasopressors, as well as to elucidate the most important clinical trials that serve as the basis of contemporary shock therapy.

Vasoactive Agent Use in Septic Shock: Beyond First-Line Recommendations

Septic shock is a life-threatening disorder associated with high mortality rates requiring rapid identification and intervention. Vasoactive agents are often required to maintain goal hemodynamics and preserve tissue perfusion. However, guidance regarding the proper administration of adjunct agents for the management of septic shock is limited in patients who are refractory to norepinephrine. This review summarizes vasopressor agents and describes the nuanced application of these agents in patients with septic shock, specifically focusing on clinical scenarios with limited guidance including patients who are nonresponsive to first-line agents and individuals with mixed shock states, tachyarrhythmias, obesity, valvular abnormalities, or other comorbid conditions.

Sepsis associated acute kidney injury

Sepsis is defined as organ dysfunction resulting from the host's deleterious response to infection. One of the most common organs affected is the kidneys, resulting in sepsis associated acute kidney injury (SA-AKI) that contributes to the morbidity and mortality of sepsis. A growing body of knowledge has illuminated the clinical risk factors, pathobiology, response to treatment, and elements of renal recovery that have advanced our ability to prevent, detect, and treat SA-AKI. Despite these advances, SA-AKI remains an important concern and clinical burden, and further study is needed to reduce the acute and chronic consequences. This review summarizes the relevant evidence, with a focus on the risk factors, early recognition and diagnosis, treatment, and long term consequences of SA-AKI. In addition to literature pertaining to SA-AKI specifically, pertinent sepsis and acute kidney injury literature relevant to SA-AKI was included.

Esmolol infusion in patients with septic shock and tachycardia: a prospective, single-arm, feasibility study

Background

High adrenergic tone appears to be associated with mortality in septic shock, while adrenergic antagonism may improve survival. In preparation for a randomized trial, we conducted a prospective, single-arm pilot study of esmolol infusion for patients with septic shock and tachycardia that persists after adequate volume expansion.

Methods

From April 2016 to March 2017, we enrolled patients admitted to an intensive care unit with sepsis who were receiving vasopressor infusion and were tachycardic despite adequate volume expansion. All patients received a continuous intravenous infusion of esmolol, targeted to heart rate 80–90/min, while receiving vasopressors. The feasibility outcomes were proportion of eligible patients consented, compliance with pre-infusion safety check, and compliance with the titration protocol. The primary clinical outcome was organ-failure-free days (OFFD) at 28 days.

Results

We enrolled 7 of 10 eligible patients. Mean age was 46 (± 19) years, and mean admission APACHE II was 28 (± 8). Median norepinephrine infusion rate at the initiation of esmolol infusion was 0.20 (0.14–0.23) μg/kg/min. Compliance with the safety check was 100%; compliance with components of the titration protocol was 98–100%. OFFD were 26 (24.5–26); all patients survived to day 90. Median peak esmolol infusion was 50 (25–50) μg/kg/min. Median peak norepinephrine infusion rate during esmolol infusion was 0.46 (0.13–0.50) μg/kg/min. Four patients achieved target heart rate. Protocol-defined stop events, suggesting possible intolerance to a given infusion rate, occurred in three patients, all of whom were receiving at least 50 μg/kg/min of esmolol.

Conclusions

In a pilot, single-arm study, we report the first published experience with esmolol infusion in tachycardic patients with septic shock in the United States. These findings support a phase 2 trial of esmolol infusion for septic shock. Lower infusion rates of esmolol infusion may be better tolerated and more feasible than higher infusion rates for such a trial.

Trial registration

This study was retrospectively registered at ClinicalTrials.gov (NCT02841241) on 19 July 2016.

Electronic supplementary material

The online version of this article (10.1186/s40814-018-0321-5) contains supplementary material, which is available to authorized users.

Sepsis-induced acute kidney injury: A disease of the microcirculation

AKI is a common complication of sepsis and is significantly associated with mortality. Sepsis accounts for more than 50% of the cases of AKI, with a mortality rate of up to 40%. The pathogenesis of septic AKI is complex, but there is emerging evidence that, at least in the first 48 hours, the defects may be functional rather than structural in nature. For example, septic AKI is associated with an absence of histopathological changes, but with microvascular abnormalities and tubular stress. In this context, renal medullary hypoxia due to redistribution of intra-renal perfusion is emerging as a critical mediator of septic AKI. Clinically, vasopressor drugs remain the cornerstone of therapy for maintenance of blood pressure and organ perfusion. However, in septic AKI, there is insensitivity to vasopressors such as norepinephrine, leading to persistent hypotension and organ failure. Vasopressin, angiotensin II, and, paradoxically, α₂ -adrenergic receptor agonists (clonidine and dexmedetomidine) may be feasible adjunct therapies for catecholamine-resistant vasodilatory shock. In this review, we outline the recent progress made in understanding how these drugs may influence the renal microcirculation, which represents a crucial step toward developing better approaches for the circulatory management of patients with septic AKI.

Hyperinflation of Vasopressors (Vasopressin, Norepinephrine, Ephedrine, etc)

PURPOSE

Hyperinflation refers to the increasing cost of drugs which occurs due to continued drug shortages and rebranding. Hyperinflation has significant implications in increasing overall healthcare costs with reduced reimbursement, increased patient acuity, and an aging population, but published strategies to reduce costs and minimize waste are limited.

OBJECTIVE

To describe the hyperinflation and cost mitigation strategies of three vasopressor medications, vasopressin, epinephrine, and ephedrine.

CONCLUSION

The steep increase in medications is expected to continue, and mitigation strategies to reduce waste and select the most cost effective therapy to offset the price increase is crucial for healthcare systems.

A global perspective on vasoactive agents in shock

PURPOSE

We set out to summarize the current knowledge on vasoactive drugs and their use in the management of shock to inform physicians' practices.

METHODS

This is a narrative review by a multidisciplinary, multinational-from six continents-panel of experts including physicians, a pharmacist, trialists, and scientists.

RESULTS AND CONCLUSIONS

Vasoactive drugs are an essential part of shock management. Catecholamines are the most commonly used vasoactive agents in the intensive care unit, and among them norepinephrine is the first-line therapy in most clinical conditions. Inotropes are indicated when myocardial function is depressed and dobutamine remains the first-line therapy. Vasoactive drugs have a narrow therapeutic spectrum and expose the patients to potentially lethal complications. Thus, these agents require precise therapeutic targets, close monitoring with titration to the minimal efficacious dose and should be weaned as promptly as possible. Moreover, the use of vasoactive drugs in shock requires an individualized approach. Vasopressin and possibly angiotensin II may be useful owing to their norepinephrine-sparing effects.

Unexplained mortality differences between septic shock trials: a systematic analysis of population characteristics and control-group mortality rates

Purpose

Although the definition of septic shock has been standardized, some variation in mortality rates among clinical trials is expected. Insights into the sources of heterogeneity may influence the design and interpretation of septic shock studies. We set out to identify inclusion criteria and baseline characteristics associated with between-trial differences in control group mortality rates.

Methods

We conducted a systematic review of RCTs published between 2006 and 2018 that included patients with septic shock. The percentage of variance in control-group mortality attributable to study heterogeneity rather than chance was measured by I². The association between control-group mortality and population characteristics was estimated using linear mixed models and a recursive partitioning algorithm.

Results

Sixty-five septic shock RCTs were included. Overall control-group mortality was 38.6%, with significant heterogeneity (I² = 93%, P < 0.0001) and a 95% prediction interval of 13.5–71.7%. The mean mortality rate did not differ between trials with different definitions of hypotension, infection or vasopressor or mechanical ventilation inclusion criteria. Population characteristics univariately associated with mortality rates were mean Sequential Organ Failure Assessment score (standardized regression coefficient (β) = 0.57, P = 0.007), mean serum creatinine (β = 0.48, P = 0.007), the proportion of patients on mechanical ventilation (β = 0.61, P < 0.001), and the proportion with vasopressors (β = 0.57, P = 0.002). Combinations of population characteristics selected with a linear model and recursive partitioning explained 41 and 42%, respectively, of the heterogeneity in mortality rates.

Conclusions

Among 65 septic shock trials, there was a clinically relevant amount of heterogeneity in control group mortality rates which was explained only partly by differences in inclusion criteria and reported baseline characteristics.

Electronic supplementary material

The online version of this article (10.1007/s00134-018-5134-8) contains supplementary material, which is available to authorized users.

Vasopressors in Sepsis

BACKGROUND

Sepsis accounts for 10% of intensive care unit admissions and significant healthcare costs. Although the mortality rate from sepsis has been decreasing with better critical care, early identification of septic patients, and prompt interventions, the mortality rate remains 20%-30%.

METHOD

Review of the English-language literature.

RESULTS

Norepinephrine is the first-line vasopressor in shock and is associated with a lower mortality rate as well as fewer adverse effects. Dopamine has similar actions but is associated with significantly more tachydysrhythmias and should be reserved for patients with bradycardia. Epinephrine and vasopressin are appropriate second-line vasopressors and may enable use of lower doses of norepinephrine while improving hemodynamics. Inotropes may be added in patients with cardiac dysfunction.

CONCLUSION

Appropriate treatment of sepsis includes prompt identification, early antimicrobial drug therapy, appropriate fluid resuscitation, and initiation of vasopressors in the presence of continued septic shock. Further research needs to be done to better understand the ideal timing of the addition of a second agent and the optimal combinations of vasopressors for individual patients.

Management of septic shock in intermediate care unit

BACKGROUND

While guidelines advocate goal-directed resuscitation based on timed bundles, the management of septic shock (SS) outside an ICU setting has been poorly studied in intermediate care units (IMCU).

PATIENTS AND METHOD

We reviewed all cases of septic shock patients admitted to our IMCU between January 2013 and June 2014. The characteristics of sepsis, compliance of bundles, and outcomes were collected. The IMCU population was compared with the SS patients admitted to the ICU during the same period. The primary objective was to evaluate the feasibility of care in an IMCU.

RESULTS

We treated 59 patients in the IMCU. Forty-three patients (73%) were fully managed in the IMCU and 16 patients (27%) were secondarily transferred to the ICU. In the first 3hours, the compliance to bundles was: blood cultures (95%), plasma lactate concentration (90%), vascular filling volume (1500ml (1000-2000)) and antibiotics (100%). A central venous line and an arterial catheter were inserted in 85% and 98.3% of the cases. At 24h, patients who were transferred to the ICU had higher lactate concentrations than the other patients (1.4±0.7mmol versus 2.9±3.4mmol; P=0.03). A 24 hours-SOFA score>4 was correlated with a transfer in ICU (OR 7,75 (95% CI 2.08-28,81; P=0.002)).

CONCLUSIONS

Our work demonstrated the ability to manage SS patients solely in an IMCU. It showed that the SS resuscitation bundle can be successfully implemented outside the ICU. A lack of improvement at the 24th hour is associated with a transfer to the ICU.