Evaluation of Vasopressin for Vasoplegic Shock in Patients With Preoperative Left Ventricular Dysfunction After Cardiac Surgery: A Propensity-Score Analysis. Shock. 2018;50:519-524. [PMID: 29424795 DOI: 10.1097/shk.0000000000001114]

Vasoplegia in Cardiac Surgery: A Systematic Review and Meta-analysis of Current Definitions and Their Influence on Clinical Outcomes

OBJECTIVES

To identify differences in the reported vasoplegia incidence, intensive care unit (ICU) length of stay (LOS), and 30-day mortality rates as influenced by different vasoplegia definitions used in cardiac surgery studies.

DESIGN

A systematic review was performed covering the period 1977 to 2023 using PubMed/MEDLINE, Embase, Web of Science, Cochrane Library, and Emcare and a meta-analysis (PROSPERO: CRD42021258328) was performed.

SETTING AND PARTICIPANTS

One hundred studies defining vasoplegia in cardiac surgery patients were systematically reviewed. Sixty studies with 20 or more patients, irrespective of design, reporting vasoplegia incidence, ICU LOS, or 30-day mortality were included for meta-analysis.

INTERVENTIONS

Cardiac surgery on cardiopulmonary bypass.

MEASUREMENTS AND MAIN RESULTS

Studies were categorized depending on the used mean arterial pressure (MAP) thresholds. Random intercept logistic regression models were used for meta-analysis of incidence and mortality. Random effect meta-analysis was used for ICU LOS. One hundred studies were reviewed systematically. MAP and cardiac index thresholds varied considerably (<50-80 mmHg and 2.0-3.5 L·min-1m-2, respectively). Vasopressor dosages also differed between definitions. The reported incidence (60 studies; mean incidence, 19.9%; 95% confidence interval [CI], 16.1-24.4) varied largely between studies (2.5%-66.3%; I2 = 97%; p < 0.0001). Meta-regression models, including the MAP-threshold, did not explain this heterogeneity. Similarly, the effect of vasoplegia on ICU LOS, and 30-day mortality was very heterogeneous among studies (I2 = 99% and I2 = 73%, respectively).

CONCLUSIONS

The large variability in vasoplegia definitions is associated with significant heterogeneity regarding incidence and clinical outcomes, which cannot be explained by factors included in our models. Such variations in definitions leads to inconsistent patient diagnosis and renders published vasoplegia research incomparable.

THE EFFECT OF CATECHOLAMINE VERSUS NONCATECHOLAMINE VASOPRESSORS ON RENAL FUNCTION AND RECOVERY IN VASODILATORY SHOCK: A SYSTEMATIC REVIEW OF PRECLINICAL AND CLINICAL STUDIES

ABSTRACT

Background: Acute kidney injury (AKI) is a common complication of vasodilatory shock. AKI is associated with an increased risk of death, prolonged hospital stays, and subsequent transition to chronic kidney disease. Catecholamines have historically been used as the first-line vasopressors for vasodilatory shock; however, they may adversely affect renal function and recovery. Objectives: To compare the effects of catecholamine and noncatecholamine vasopressors on AKI risk and recovery in preclinical and clinical studies of vasodilatory shock. Methods: MEDLINE, Embase, and Cochrane Central Register of Controlled Trials were systematically searched to identify studies reporting renal outcomes associated with catecholamine (norepinephrine, epinephrine, metaraminol, phenylephrine, dopamine) and noncatecholamine vasopressors (vasopressin, angiotensin II), in preclinical models or adult cohorts of vasodilatory shock. Two independent reviewers screened studies and extracted data using a prespecified form for qualitative synthesis and risk of bias assessment. Results: Of 3,504 citations, 90 studies were eligible for inclusion: 41 preclinical studies, 17 nonrandomized clinical studies, 28 randomized clinical studies, and 4 post-hoc analyses. Risk of bias was generally low in preclinical studies and low to moderate in clinical studies. In preclinical studies, catecholamine vasopressors exacerbated medullary hypoxia and intrarenal inflammation compared to noncatecholamine vasopressors. In clinical studies, catecholamines were associated with higher serum creatinine, lower urine output, and increased requirements for renal replacement therapy compared to noncatecholamine vasopressors. In patients on high-dose catecholamines, adjunctive angiotensin II was associated with improved renal replacement therapy liberation. Conclusion: Preclinical and clinical studies suggest that noncatecholamine vasopressors may confer renal benefits compared to catecholamine vasopressors. These hypothesis-generating observations suggest the need for comparative studies focused on renal outcomes. Systematic Review Registration : PROSPERO 2024 CRD42024527773.

Hemodynamic Management with Vasopressin for Cardiovascular Surgery

Background and Objectives: Vasopressin increases blood pressure through aquaporin-2-mediated water retention and is useful for managing hemodynamics after surgery. However, even after decades of study, clear clinical guidelines on doses and ideal use cases after cardiovascular surgery remain unclear. Here, the existing literature is synthesized on vasopressin use for cardiac surgeries and coupled with real-world clinical experience to outline a clearer clinical path for vasopressin use. Materials and Methods: Literature from 1966 to the present was searched, and information on surgical outcomes for cardiovascular surgery was extracted. Clinicians from the University of Tsukuba with extensive vasopressin experience in pediatric cardiovascular patients were consulted for general use guidelines. Results: Vasopressin response after cardiovascular surgery is multifaceted, and low-power trials, plus conflicting study reports, generally render it as a secondary choice behind norepinephrine. Clinical experience indicates that low doses of 0.2-0.3 mU/kg/min with constant blood pressure and oxygen monitoring for response are required. Although sole use is not recommended, vasopressin may aid in controlling hemodynamics when given with other volemic or osmolal drugs. Conclusions: Vasopressin may work in a select population of first-line non-responders, but relevant response factors remain unanalyzed and clear guidelines for use remain unestablished. Future, large-scale studies are needed to delineate temporal and demographic characteristics that affect response to vasopressin for the purpose of managing post-surgical capillary leakage and hemodynamics.

Pharmacotherapy of acute ST-elevation myocardial infarction and the pharmacist's role, part 2: Complications, postrevascularization care, and quality improvement

DISCLAIMER

In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

Key pharmacotherapeutic modalities and considerations for the patient with ST-elevation myocardial infarction (STEMI) across the later phases of inpatient care are reviewed.

SUMMARY

Published descriptions and validation of clinical pharmacist roles specific to the acute management of STEMI are limited. This high-risk period from presentation through revascularization, stabilization, and hospital discharge involves complex pharmacotherapeutic decision points, many operational medication needs, and multiple layers of quality oversight. A companion article reviewed STEMI pharmacotherapy from emergency department presentation through revascularization. Herein we complete the pharmacotherapy review for the STEMI patient across the inpatient phases of care, including the management of peri-infarction complications with vasoactive and antiarrhythmic agents, considerations for postrevascularization antithrombotics, and assessments of supportive therapies and secondary prevention. Key guideline recommendations and literature developments are summarized from the clinical pharmacist's perspective alongside suggested pharmacist roles and responsibilities. Considerations for successful hospital discharge after STEMI and pharmacist involvement in associated institutional quality improvement efforts are also provided. We aim to support inpatient pharmacy departments in advancing clinical services for this critical patient population and call for further research delineating pharmacists' impact on patient and institutional STEMI outcomes.

Factors associated with vasoplegic shock in the postoperative period of cardiac surgery and influence on morbidity and mortality of the use of arginine vasopressin as rescue therapy

OBJECTIVES

Analyzing associated factors with vasoplegic shock in the postoperative period of Cardiac Surgery. Analyzing the influence of vasopressin as rescue therapy to first-line treatment with norepinephrine.

DESIGN

Cohort, prospective and observational study.

SETTING

Main hospital Postoperative Cardiac ICU.

PATIENTS

Patients undergoing cardiac surgery with subsequent ICU admission from January 2021 to December 2022.

INTERVENTIONS

Record of presurgical, perioperative and ICU discharge clinical variables.

MAIN VARIABLES OF INTEREST

chronic treatment, presence of vasoplegic shock, need for vasopressin, cardiopulmonary bypass time, mortality.

RESULTS

773 patients met the inclusion criteria. The average age was 67.3, with predominance of males (65.7%). Post-CPB vasoplegia was documented in 94 patients (12.2%). In multivariate analysis, vasoplegia was associated with age, female sex, presurgical creatinine levels, cardiopulmonary bypass time, lactate level upon admission to the ICU, and need for prothrombin complex transfusion. Of the patients who developed vasoplegia, 18 (19%) required rescue vasopressin, associated with pre-surgical intake of ACEIs/ARBs, worse Euroscore score and longer cardiopulmonary bypass time. Refractory vasoplegia with vasopressin requirement was associated with increased morbidity and mortality.

CONCLUSIONS

Postcardiopulmonary bypass vasoplegia is associated with increased mortality and morbidity. Shortening cardiopulmonary bypass times and minimizing products blood transfusion could reduce its development. Removing ACEIs and ARBs prior to surgery could reduce the incidence of refractory vasoplegia requiring rescue with vasopressin. The first-line treatment is norepinephrine and rescue treatment with VSP is a good choice in refractory situations. The first-line treatment of this syndrome is norepinephrine, although rescue with vasopressin is a good complement in refractory situations.

Vasopressin in vasoplegic shock in surgical patients: systematic review and meta-analysis

PURPOSE

Vasoplegia, or vasoplegic shock, is a syndrome whose main characteristic is reducing blood pressure in the presence of a standard or high cardiac output. For the treatment, vasopressors are recommended, and the most used is norepinephrine. However, new drugs have been evaluated, and conflicting results exist in the literature.

METHODS

This is a systematic review of the literature with meta-analysis, written according to the recommendations of the PRISMA report. The SCOPUS, PubMed, and ScienceDirect databases were used to select the scientific articles included in the study. Searches were conducted in December 2022 using the terms "vasopressin," "norepinephrine," "vasoplegic shock," "postoperative," and "surgery." Meta-analysis was performed using Review Manager (RevMan) 5.4. The endpoint associated with the study was efficiency in treating vasoplegic shock and reduced risk of death.

RESULTS

In total, 2,090 articles were retrieved; after applying the inclusion and exclusion criteria, ten studies were selected to compose the present review. We found no significant difference when assessing the outcome mortality comparing vasopressin versus norepinephrine (odds ratio = 1.60; confidence interval 0.47-5.50), nor when comparing studies on vasopressin versus placebo. When we analyzed the length of hospital stay compared to the use of vasopressin and norepinephrine, we identified a shorter length of hospital stay in cases that used vasopressin; however, the meta-analysis did not demonstrate statistical significance.

CONCLUSIONS

Considering the outcomes included in our study, it is worth noting that most studies showed that using vasopressin was safe and can be considered in managing postoperative vasoplegic shock.

Dexmedetomidine as an anesthetic adjunct is associated with reduced complications and cardiac intensive care unit length of stay after heart valve surgery

BACKGROUND

We sought to explore the relationship between dexmedetomidine as an anesthetic adjuvant in cardiac surgery and postoperative complications and length of stay (LOS) in the cardiac intensive care unit (CICU).

METHODS

We conducted a retrospective study of patients aged 18 years and older who underwent heart valve surgery between October 2020 and June 2022. The primary endpoint of the study was major postoperative complications (cardiac arrest, atrial fibrillation, myocardial injury/infarction, heart failure) and the secondary endpoint was prolonged CICU LOS (defined as LOS > 90th percentile). Multivariate logistic regression analysis was performed for variables that were significant in the univariate analysis.

RESULTS

A total of 856 patients entered our study. The 283 patients who experienced the primary and secondary endpoints were included in the adverse outcomes group, and the remaining 573 were included in the prognostic control group. Multivariate logistic regression analysis revealed that age > 60 years (odds ratio [OR], 1.68; 95% confidence interval [CI], 1.23-2.31; p < 0.01), cardiopulmonary bypass (CPB) > 180 min (OR, 1.62; 95% CI, 1.03-2.55; p = 0.04) and postoperative mechanical ventilation time > 10 h (OR, 1.84; 95% CI, 1.35-2.52; p < 0.01) were independent risk factors for major postoperative complications; Age > 60 years (OR, 3.20; 95% CI, 1.65-6.20; p < 0.01), preoperative NYHA class 4 (OR, 4.03; 95% CI, 1.74-9.33; p < 0.01), diabetes mellitus (OR, 2.57; 95% CI, 1.22-5.41; p = 0.01), Intraoperative red blood cell (RBC) transfusion > 650 ml (OR, 2.04; 95% CI, 1.13-3.66; p = 0.02), Intraoperative bleeding > 1200 ml (OR, 2.69; 95% CI, 1.42-5.12; p < 0.01) were independent risk factors for prolonged CICU length of stay. Intraoperative use of dexmedetomidine as an anesthetic adjunct was a protective factor for major complications (odds ratio, 0.51; 95% confidence interval, 0.35-0.74; p < 0.01) and prolonged CICU stay. (odds ratio, 0.37; 95% confidence interval, 0.19-0.73; p < 0.01).

CONCLUSIONS

In patients undergoing heart valve surgery, age, duration of cardiopulmonary bypass, and duration of mechanical ventilation are associated with major postoperative complication. Age, preoperative NYHA classification 4, diabetes mellitus, intraoperative bleeding, and RBC transfusion are associated with increased CICU length of stay. Intraoperative use of dexmedetomidine may improve such clinical outcomes.

Risk factors for postoperative myocardial injury-related cardiogenic shock in patients undergoing cardiac surgery

BACKGROUND

Myocardial injury-related cardiogenic shock (MICS) is significantly associated with poor outcomes in patients after cardiac surgery. Herein, we aimed to investigate the risk factor for postoperative MICS.

METHODS

We performed a case-control study on 792 patients undergoing cardiac surgery from 2016 to 2019, including 172 patients with postoperative MICS and 620 age- and sex-matched controls. MICS was defined as composite criteria: a cardiac index of < 2.2 L/m²/min, arterial lactate levels of > 5 mmol/L at the end of the surgery, a vasoactive-inotropic score of > 40 at the end of the surgery, and a cardiac troponin T (cTnT) level of > 0.8 µg/L on postoperative day 1 (POD1) with an increase of > 10% on POD 2.

RESULTS

A total of 4671 patients who underwent cardiac surgery in our hospital between 2016 and 2019 were included; of these, 172 (3.68%) had MICS and the remaining 4499 did not. For investigating the risk factors, we selected 620 age- and sex-matched controls. In the univariate analysis, MICS was significantly associated with death (P < 0.05), extracorporeal membrane oxygenation (P < 0.05), continuous renal replacement therapy (P < 0.01), and ventricular arrhythmias (P < 0.05). Multivariable logistic regression analysis revealed that diabetes mellitus (OR:8.11, 95% CI: 3.52-18.66, P < 0.05) and a cardiopulmonary bypass (CPB) time of > 2 h (OR: 3.16, 95% CI: 1.94-5.15, P < 0.05) were associated with postoperative MICS. Moreover, long-time administration of preoperative calcium channel blocker (CCB) was associated with a less incidence of MICS (OR: 0.11, 95% CI: 0.05-0.27, P < 0.05).

CONCLUSIONS

Postoperative MICS is significantly associated with poor outcomes. Diabetes mellitus and long CPB time are associated with MICS. Preoperative CCB administration is associated with less incidence of MICS.

Use of Vasoactive Medications after Cardiac Surgery in the United States

Rationale: Patients undergoing cardiac surgery often require vasopressor or inotropic ("vasoactive") medications, but patterns of postoperative use are not well described.Objectives: This study aimed to describe vasoactive medication administration throughout hospitalization for cardiac surgery, to identify patient- and hospital-level factors associated with postoperative use, and to quantify variation in treatment patterns among hospitals.Methods: Retrospective study using the Premier Healthcare Database. The cohort included adult patients who underwent coronary artery bypass grafting or open valve repair or replacement (or in combination) from January 1, 2016, to June 30, 2018. Primary outcome was receipt of vasoactive medication(s) on the first postoperative day (POD1). We identified patient- and hospital-level factors associated with receipt of vasoactive medications using multilevel mixed-effects logistic regression modeling. We calculated adjusted median odds ratios to determine the extent to which receipt of vasoactive medications on POD1 was determined by each hospital, then calculated quotients of Akaike Information Criteria to compare the relative contributions of patient and hospital characteristics and individual hospitals with observed variation.Results: Among 104,963 adults in 294 hospitals, 95,992 (92.2%) received vasoactive medication(s) during hospitalization; 30,851 (29.7%) received treatment on POD1, most commonly norepinephrine (n = 11,427, 37.0%). A median of 29.0% (range, 0.0-94.4%) of patients in each hospital received vasoactive drug(s) on POD1. After adjustment, hospital of admission was associated with twofold increased odds of receipt of any vasoactive medication on POD1 (adjusted median odds ratio, 2.07; 95% confidence interval, 1.93-2.21). Admitting hospital contributed more to observed variation in POD1 vasoactive medication use than patient or hospital characteristics (quotients of Akaike Information Criteria 0.58, 0.44, and <0.001, respectively).Conclusions: Nearly all cardiac surgical patients receive vasoactive medications during hospitalization; however, only one-third receive treatment on POD1, with significant variability by institution. Further research is needed to understand the causes of variability across hospitals and whether these differences are associated with outcomes.

Vasopressin in vasoplegic shock: A systematic review

BACKGROUND

Vasoplegic shock is a challenging complication of cardiac surgery and is often resistant to conventional therapies for shock. Norepinephrine and epinephrine are standards of care for vasoplegic shock, but vasopressin has increasingly been used as a primary pressor in vasoplegic shock because of its unique pharmacology and lack of inotropic activity. It remains unclear whether vasopressin has distinct benefits over standard of care for patients with vasoplegic shock.

AIM

To summarize the available literature evaluating vasopressin vs non-vasopressin alternatives on the clinical and patient-centered outcomes of vasoplegic shock in adult intensive care unit (ICU) patients.

METHODS

This was a systematic review of vasopressin in adults (≥ 18 years) with vasoplegic shock after cardiac surgery. Randomized controlled trials, prospective cohorts, and retrospective cohorts comparing vasopressin to norepinephrine, epinephrine, methylene blue, hydroxocobalamin, or other pressors were included. The primary outcomes of interest were 30-d mortality, atrial/ventricular arrhythmias, stroke, ICU length of stay, duration of vasopressor therapy, incidence of acute kidney injury stage II-III, and mechanical ventilation for greater than 48 h.

RESULTS

A total of 1161 studies were screened for inclusion with 3 meeting inclusion criteria with a total of 708 patients. Two studies were randomized controlled trials and one was a retrospective cohort study. Primary outcomes of 30-d mortality, stroke, ventricular arrhythmias, and duration of mechanical ventilation were similar between groups. Conflicting results were observed for acute kidney injury stage II-III, atrial arrhythmias, duration of vasopressors, and ICU length of stay with higher certainty of evidence in favor of vasopressin serving a protective role for these outcomes.

CONCLUSION

Vasopressin was not found to be superior to alternative pressor therapy for any of the included outcomes. Results are limited by mixed methodologies, small overall sample size, and heterogenous populations.

Comparison of Hemodynamic Responses to Administration of Vasopressin and Norepinephrine Under General Anesthesia: A Systematic Review and Meta-analysis of Randomized Controlled Trials with Trial Sequential Analysis

OBJECTIVE

The authors performed a meta-analysis to determine if vasopressin improves hypotension more than norepinephrine under general anesthesia.

DESIGN

Meta-analysis.

SETTING

Operating room.

PATIENTS

Patients who underwent surgery, with general anesthesia.

INTERVENTIONS

Administration of vasopressin or norepinephrine in order to increase blood pressure.

MEASUREMENTS AND MAIN RESULTS

The primary outcome of this study was to determine if vasopressin increased mean blood pressure more effectively compared with norepinephrine for patients under general anesthesia. The secondary outcome was to see if vasopressin increased heart rate (HR), central venous pressure (CVP), cardiac output (CO), and cardiac index (CI) more significantly compared with norepinephrine under general anesthesia. The authors calculated the weighted mean difference, with 95% confidence interval (CI) using the random-effects model, and calculated the required information size (RIS) by performing trial sequential analysis (TSA). The authors selected 6 studies for analysis. Vasopressin did not improve hypotension compared with norepinephrine under general anesthesia. (weighted mean difference = -0.84 mmHg, 95% CI: -5.90 to 4.23, p = 0.75, Cochran Q = 24.6, I² = 84%) In TSA, only 35.5% of RIS was achieved. Similarly, vasopressin and norepinephrine were not significantly different in terms of HR, CVP, CO, and CI. In TSA, only 23.7% of the RIS was reached for HR but RIS was almost achieved for CVP and CO.

CONCLUSIONS

Vasopressin did not improve hypotension compared with norepinephrine under general anesthesia. The RIS was not reached in TSA, and Grading of Recommendations Assessment, Development and Evaluation is very low. Therefore, further research is needed to reach more robust conclusions.

Vasoplegia after cardiopulmonary bypass: A narrative review of pathophysiology and emerging targeted therapies

Cardiovascular disease remains the leading cause of death in the United States, and cardiopulmonary bypass is a cornerstone in the surgical management of many related disease states. Pathophysiologic changes associated both with extracorporeal circulation and shock can beget a syndrome of low systemic vascular resistance paired with relatively preserved cardiac output, termed vasoplegia. While increased vasopressor requirements accompany vasoplegia, related pathophysiologic mechanisms may also lead to true catecholamine resistance, which is associated with further heightened mortality. The introduction of a second non-catecholamine vasopressor, angiotensin II, and non-specific nitric oxide scavengers offers potential means by which to manage this challenging phenomenon. This narrative review addresses both the definition, risk factors, and pathophysiology of vasoplegia and potential therapeutic interventions.

Heparin-binding protein measurement improves the prediction of myocardial injury-related cardiogenic shock

Background

Heparin-binding protein (HBP), a potent inducer of increased vascular permeability, is a potentially useful biomarker for predicting outcomes in patients with postoperative myocardial injury-related cardiogenic shock (MIRCS). We aimed to evaluate and validate HBP as a prognostic biomarker for postoperative MIRCS.

Methods

We performed a case-control study in 792 patients undergoing cardiac surgery from January 1, 2016, to August 1, 2019, including 172 patients with postoperative MIRCS and 620 age- and sex-matched controls. The association between HBP and MIRCS was determined by multivariate logistic regression analysis. Receiver operating characteristic curves (ROCs) with area under the curve (AUC) were performed to calculate the cut-off value, sensitivity and specificity. The association between HBP and cardiac troponin T (cTnT) was determined by multivariable linear regression analysis. Blood samples were drawn from the coronary sinus and arterial line of the cardiopulmonary bypass (CPB) before aortic cross-clamping (time point 1) and 5 min after aortic declamping (time point 2).

Results

Before aortic cross-clamping, coronary sinus HBP (HBP_CS1) showed no differences between the two groups. However, after declamping, the MIRCS group had a significantly higher sinus HBP level (HBP_CS2) than did the control group. HBP_CS2 predicted MIRCS with an AUC of 0.85 (95% CI: 0.81–0.89, cut-off: 220 ng/ml, sensitivity: 92% and specificity: 70%). After adjusting for confounding factors, we found that HBP was an independent risk factor for MIRCS (OR: 7.65, 95% CI: 4.86–12.06, P < 0.01) and was positively associated with cTnT (β > 0, P < 0.01).

Conclusions

Elevated levels of coronary sinus HBP were useful biomarkers for predicting MIRCS after cardiac surgery.

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.

Arginine vasopressin modulates electrical activity and calcium homeostasis in pulmonary vein cardiomyocytes

Background

Atrial fibrillation (AF) frequently coexists with congestive heart failure (HF) and arginine vasopressin (AVP) V1 receptor antagonists are used to treat hyponatremia in HF. However, the role of AVP in HF-induced AF still remains unclear. Pulmonary veins (PVs) are central in the genesis of AF. The purpose of this study was to determine if AVP is directly involved in the regulation of PV electrophysiological properties and calcium (Ca²⁺) homeostasis as well as the identification of the underlying mechanisms.

Methods

Patch clamp, confocal microscopy with Fluo-3 fluorescence, and Western blot analyses were used to evaluate the electrophysiological characteristics, Ca²⁺ homeostasis, and Ca²⁺ regulatory proteins in isolated rabbit single PV cardiomyocytes incubated with and without AVP (1 μM), OPC 21268 (0.1 μM, AVP V1 antagonist), or OPC 41061 (10 nM, AVP V2 antagonist) for 4–6 h.

Results

AVP (0.1 and 1 μM)-treated PV cardiomyocytes had a faster beating rate (108 to 152%) than the control cells. AVP (1 μM) treated PV cardiomyocytes had higher late sodium (Na⁺) and Na⁺/Ca²⁺ exchanger (NCX) currents than control PV cardiomyocytes. AVP (1 μM) treated PV cardiomyocytes had smaller Ca²⁺_i transients, and sarcoplasmic reticulum (SR) Ca²⁺ content as well as higher Ca²⁺ leak. However, combined AVP (1 μM) and OPC 21268 (0.1 μM) treated PV cardiomyocytes had a slower PV beating rate, larger Ca²⁺_i transients and SR Ca²⁺ content, smaller late Na⁺ and NCX currents than AVP (1 μM)-treated PV cardiomyocytes. Western blot experiments showed that AVP (1 μM) treated PV cardiomyocytes had higher expression of NCX and p-CaMKII, and a higher ratio of p-CaMKII/CaMKII.

Conclusions

AVP increases PV arrhythmogenesis with dysregulated Ca²⁺ homeostasis through vasopressin V1 signaling.

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.