Vasopressin administration in refractory cardiac arrest

Therapeutic effects of vasopressin on cardiac arrest: a systematic review and meta-analysis

OBJECTIVE

To demonstrate the therapeutic effect of vasopressin as an alternative treatment for cardiac arrest.

DESIGN

Systematic review and meta-analysis.

METHODS

PubMed, EMBASE, the Cochrane Library and Web of Science were searched for randomised controlled trials. The intervention included administration of vasopressin alone or vasopressin combined with epinephrine or vasopressin, steroids and epinephrine (VSE) versus epinephrine combined with placebo as control group. The primary outcome was the return of spontaneous circulation (ROSC). The secondary outcomes included mid-term survival and mid-term good neurological outcome. We conducted subgroup analyses of the primary outcome based on different settings, different study drug strategies and different types of initial rhythm.

RESULTS

Twelve studies (n=6718) were included, of which eight trials (n=5638) reported the data on patients with out-of-hospital cardiac arrest and four trials (n=1080) on patients with in-hospital cardiac arrest (IHCA). There were no significant differences between intravenous vasopressin and placebo in the outcomes of ROSC (relative risk (RR): 1.11; 95% CI: 0.99 to 1.26), mid-term survival (RR: 1.23; 95% CI: 0.90 to 1.66) and mid-term good neurological outcome (RR: 1.20; 95% CI: 0.77 to 1.87). However, in the subgroup analysis, intravenous vasopressin as part of VSE can significantly improve the rate of ROSC (RR: 1.32; 95% CI: 1.18 to 1.47) but not the rate of mid-term survival (RR: 2.15; 95% CI: 0.75 to 6.16) and mid-term good neurological outcome (RR: 1.80; 95% CI: 0.81 to 4.01) for patients with IHCA.

CONCLUSIONS

Our study failed to demonstrate increased benefit from vasopressin with or without epinephrine compared with the standard of care. However, vasopressin as a part of VSE is associated with the improvement of ROSC in patients with IHCA, and the benefit on mid-term survival or mid-term good neurological outcome is uncertain. Larger trials should be conducted in the future to address the effect of vasopressin only, vasopressin plus epinephrine or VSE on cardiac arrest.

PROSPERO REGISTRATION NUMBER

CRD42021293347.

The Heart as a Target of Vasopressin and Other Cardiovascular Peptides in Health and Cardiovascular Diseases

The automatism of cardiac pacemaker cells, which is tuned, is regulated by the autonomic nervous system (ANS) and multiple endocrine and paracrine factors, including cardiovascular peptides. The cardiovascular peptides (CPs) form a group of essential paracrine factors affecting the function of the heart and vessels. They may also be produced in other organs and penetrate to the heart via systemic circulation. The present review draws attention to the role of vasopressin (AVP) and some other cardiovascular peptides (angiotensins, oxytocin, cytokines) in the regulation of the cardiovascular system in health and cardiovascular diseases, especially in post-infarct heart failure, hypertension and cerebrovascular strokes. Vasopressin is synthesized mostly by the neuroendocrine cells of the hypothalamus. There is also evidence that it may be produced in the heart and lungs. The secretion of AVP and other CPs is markedly influenced by changes in blood volume and pressure, as well as by other disturbances, frequently occurring in cardiovascular diseases (hypoxia, pain, stress, inflammation). Myocardial infarction, hypertension and cardiovascular shock are associated with an increased secretion of AVP and altered responsiveness of the cardiovascular system to its action. The majority of experimental studies show that the administration of vasopressin during ventricular fibrillation and cardiac arrest improves resuscitation, however, the clinical studies do not present consisting results. Vasopressin cooperates with the autonomic nervous system (ANS), angiotensins, oxytocin and cytokines in the regulation of the cardiovascular system and its interaction with these regulators is altered during heart failure and hypertension. It is likely that the differences in interactions of AVP with ANS and other CPs have a significant impact on the responsiveness of the cardiovascular system to vasopressin in specific cardiovascular disorders.

Efficacy of combination triple therapy with vasopressin, steroid, and epinephrine in cardiac arrest: a systematic review and meta-analysis of randomized-controlled trials

Background

This study investigated whether combination therapy with vasopressin, steroid, and epinephrine (VSE) improves in-hospital survival and return of spontaneous circulation (ROSC) during and after resuscitation in-hospital cardiac arrest (CA).

Materials and methods

Various databases were explored from inception until October 2021 for relevant published clinical trials and cohort studies.

Results

Three clinical trials were included. Pooled analysis suggested that VSE was significantly associated with increased ROSC in patients with in-hospital CA (IHCA) (odds ratio (OR): 2.281, 95% confidence interval (CI): 1.304–3.989, P value = 0.004). Meta-analysis of two studies (368 patients) demonstrated a significant difference in the reduction of mean arterial pressure (MAP) during and 15–20 min after cardiopulmonary resuscitation (standardized mean difference (SMD): 1.069, 95% CI: 0.851–1.288, P value < 0.001), renal failure free days (SMD = 0.590; 95% CI: 0.312–0.869 days; P value < 0.001), and coagulation failure free days (SMD = 0.403; 95% CI: 0.128–0.679, P value = 0.004). However, no significant difference was observed for survival-to-discharge ratio (OR: 2.082, 95% CI: 0.638–6.796, P value = 0.225) and ventilator free days (SMD = 0.201, 95% CI: − 0.677, 1.079 days; P value = 0.838).

Conclusions

VSE combination therapy during and after IHCA may have beneficial effects in terms of the ROSC, renal and circulatory failure free days, and MAP.

Prospero registration: CRD42020178297 (05/07/2020).

Supplementary Information

The online version contains supplementary material available at 10.1186/s40560-022-00597-5.

Trends Over Time in Drug Administration During Adult In-Hospital Cardiac Arrest

OBJECTIVES

Clinical providers have access to a number of pharmacologic agents during in-hospital cardiac arrest. Few studies have explored medication administration patterns during in-hospital cardiac arrest. Herein, we examine trends in use of pharmacologic interventions during in-hospital cardiac arrest both over time and with respect to the American Heart Association Advanced Cardiac Life Support guideline updates.

DESIGN

Observational cohort study.

SETTING

Hospitals contributing data to the American Heart Association Get With The Guidelines-Resuscitation database between 2001 and 2016.

PATIENTS

Adult in-hospital cardiac arrest patients.

INTERVENTIONS

The percentage of patients receiving epinephrine, vasopressin, amiodarone, lidocaine, atropine, bicarbonate, calcium, magnesium, and dextrose each year were calculated in patients with shockable and nonshockable initial rhythms. Hierarchical multivariable logistic regression was used to determine the annual adjusted odds of medication administration. An interrupted time series analysis was performed to assess change in atropine use after the 2010 American Heart Association guideline update.

MEASUREMENTS AND MAIN RESULTS

A total of 268,031 index in-hospital cardiac arrests were included. As compared to 2001, the adjusted odds ratio of receiving each medication in 2016 were epinephrine (adjusted odds ratio, 1.5; 95% CI, 1.3-1.8), vasopressin (adjusted odds ratio, 1.5; 95% CI, 1.1-2.1), amiodarone (adjusted odds ratio, 3.4; 95% CI, 2.9-4.0), lidocaine (adjusted odds ratio, 0.2; 95% CI, 0.2-0.2), atropine (adjusted odds ratio, 0.07; 95% CI, 0.06-0.08), bicarbonate (adjusted odds ratio, 2.0; 95% CI, 1.8-2.3), calcium (adjusted odds ratio, 2.0; 95% CI, 1.7-2.3), magnesium (adjusted odds ratio, 2.2; 95% CI, 1.9-2.7; p < 0.0001), and dextrose (adjusted odds ratio, 2.8; 95% CI, 2.3-3.4). Following the 2010 American Heart Association guideline update, there was a downward step change in the intercept and slope change in atropine use (p < 0.0001).

CONCLUSIONS

Prescribing patterns during in-hospital cardiac arrest have changed significantly over time. Changes to American Heart Association Advanced Cardiac Life Support guidelines have had a rapid and substantial effect on the use of a number of commonly used in-hospital cardiac arrest medications.

Epinephrine in Neonatal Resuscitation

Epinephrine is the only medication recommended by the International Liaison Committee on Resuscitation for use in newborn resuscitation. Strong evidence from large clinical trials is lacking owing to the infrequent use of epinephrine during neonatal resuscitation. Current recommendations are weak as they are extrapolated from animal models or pediatric and adult studies that do not adequately depict the transitioning circulation and fluid-filled lungs of the newborn in the delivery room. Many gaps in knowledge including the optimal dosing, best route and timing of epinephrine administration warrant further studies. Experiments on a well-established ovine model of perinatal asphyxial cardiac arrest closely mimicking the newborn infant provide important information that can guide future clinical trials.

Vasopressin: Applications in Clinical Practice

Arginine vasopressin is a peptide produced in the posterior pituitary whose primary physiologic role is fluid homeostasis. Recent investigations have demonstrated a therapeutic role for arginine vasopressin in adult cardiac arrest as well as adult and pediatric vasodilatory shock. We review the physiology of arginine vasopressin and examine the supporting data behind the developing clinical applications of this naturally produced peptide.

Arginine Vasopressin for Refractory Distributive Shock in Two Adolescents

Arginine vasopressin is a nine amino acid peptide, most commonly known as antidiuretic hormone. Recent investigations in the areas of cardiopulmonary resuscitation and the treatment of distributive shock have suggested its possible therapeutic potential. Despite increasing experience in the adult population, there is limited experience with vasopressin administration in pediatric patients. The author reports the use of vasopressin in the treatment of refractory distributive shock in two adolescents. Previous reports of its use and potential therapeutic applications are reviewed.

A tourniquet assisted cardiopulmonary resuscitation augments myocardial perfusion in a porcine model of cardiac arrest

OBJECTIVE

During cardiopulmonary resuscitation (CPR), myocardial blood flow generated by chest compression rarely exceeds 35% of its normal level. Cardiac output generated by chest compression decreases gradually with the prolongation of cardiac arrest and resuscitation. Early studies have demonstrated that myocardial blood flow during CPR is largely dependent on peripheral vascular resistance. In this study, we investigated the effects of chest compression in combination with physical control of peripheral vascular resistance assisted by tourniquets on myocardial blood flow during CPR.

METHODS

Ventricular fibrillation was induced and untreated for 7 min in ten male domestic pigs weighing between 33 and 37 kg. The animals were then randomized to receive CPR alone or a tourniquet assisted CPR (T-CPR). In the CPR alone group, chest compression was performed by a miniaturized mechanical chest compressor. In the T-CPR group, coincident with the start of resuscitation, the thin elastic tourniquets were wrapped around the four limbs from the distal end to the proximal part. After 2 min of CPR, epinephrine (20 μg/kg) was administered via the femoral vein. After 5 min of CPR, defibrillation was attempted by a single 150 J shock. If resuscitation was not successful, CPR was resumed for 2 min before the next defibrillation. The protocol was continued until successful resuscitation or for a total of 15 min. Five minutes after resuscitation, the elastic tourniquets were removed. The resuscitated animals were observed for 2h.

RESULTS

T-CPR generated significantly greater coronary perfusion pressure, end-tidal carbon dioxide and carotid blood flow. There was no difference in both intrathoracic positive and negative pressures between the two groups. All animals were successfully resuscitated with a single shock in both groups. There were no significant changes in hemodynamics observed in the animals treated in the T-CPR group before-and-after the release of tourniquets at post-resuscitation 5 min.

CONCLUSIONS

T-CPR improves myocardial and cerebral perfusion during CPR. It may provide a new and convenient method for augmenting myocardial and cerebral blood flow during CPR.

Vasopressin improves survival compared with epinephrine in a neonatal piglet model of asphyxial cardiac arrest

BACKGROUND

Epinephrine is a component of all resuscitation algorithms. Vasopressin is a pulmonary vasodilator and systemic vasopressor. We investigated the effect of epinephrine vs. vasopressin on survival and hemodynamics after neonatal porcine cardiac arrest (CA).

METHODS

A 4-min asphyxial CA was induced, after which cardiopulmonary resuscitation (CPR) was commenced. Animals were randomized to low- (LDE: 0.01 mg/kg) or high-dose epinephrine (HDE: 0.03 mg/kg), low- (LDV: 0.2 U/kg) or high-dose vasopressin (HDV: 0.4 U/kg), or control (saline). Clinical and echocardiography indexes were monitored.

RESULTS

Sixty-nine animals were randomized. Survival was greater in HDV (n = 8 (89%); P < 0.05 ANOVA) vs. control (n = 7 (43%)) and LDE (n = 5 (36%)) but not vs. HDE (n = 7 (64%)) or LDV (n = 6 (75%)). Animals resuscitated with LDE required more shocks (2.5 (interquartile range: 2-6); P < 0.05) and higher doses of energy (15 J (interquartile range: 10-20); P < 0.05). Left ventricular output was comparable between groups, but a greater increase in superior vena caval flow was seen after HDV (P < 0.001 vs. control, LDE, and HDE). Plasma troponin was greatest in the HDE group (P < 0.05 vs. control and HDV).

CONCLUSION

Vasopressin results in improved survival, lower postresuscitation troponin, and less hemodynamic compromise after CA in newborn piglets. Vasopressin may be a candidate for testing in human neonates.

Comparison of Two Protocols for Pulseless Cardiopulmonary Arrest: Vasopressin Combined with Epinephrine Versus Epinephrine Alone

Introduction:

Survival from pulseless cardiac arrest typically is dismal. Some suggest that adding vasopressin to epinephrine as a cardiovascular stimulant can improve outcomes.

Problem:

This study compares survival outcomes using epinephrine verses vasopressin and epinephrine in persons with pulseless cardiac arrest.

Methods:

This is a retrospective, cohort evaluation of two resuscitative protocols (P1-epinephrine or P2-vasopressin with epinephrine) in a tiered response, community emergency medical service (EMS) with an approximately 100,000 catchment area. Cases are defined as 18 years or older determined to be in pulseless cardiac arrest. Outcomes were survival to emergency department arrival, to 24 hours, and to hospital discharge. Data were entered into Microsoft Office Excel® and processed using Analyze-it® for continuous and categorical data and Epi-Info® for odds ratios with confidence intervals.

Results:

There were 204 cases (60.3% males and 39.7% females) who met the inclusion criteria. Thirteen cases received electrical therapy only, and were dropped from analysis, leaving 191 (93.6%) who were included in the study; P1 to 85 (44.5%) and P2 to 106 (55.5%). Younger age was associated with improved survival to discharge home in both protocols, p = 0.003 (95% CI = 0.004–0.010). No difference in survival was noted at the levels of emergency department arrival OR 1.42 (95% CI = 0.73, 2.76) p = 0.26; 24 hour survival OR 0.54 (95% CI = 0.22–1.30) p = 0.133, or discharge home OR = 1.81 (95% CI = 0.49–6.88) p = 0.319.

Conclusions:

This study in a community EMS did not demonstrate improved survival with the addition of vasopressin to epinephrine for pulseless cardiac arrest.

Vasopressin: Its current role in anesthetic practice

Vasopressin or antidiuretic hormone is a potent endogenous hormone, which is responsible for regulating plasma osmolality and volume. In high concentrations, it also raises blood pressure by inducing moderate vasoconstriction. It acts as a neurotransmitter in the brain to control circadian rhythm, thermoregulation and adrenocorticotropic hormone release. The therapeutic use of vasopressin has become increasingly important in the critical care environment in the management of cranial diabetes insipidus, bleeding abnormalities, esophageal variceal hemorrhage, asystolic cardiac arrest and septic shock. After 10 years of ongoing research, vasopressin has grown to a potential component as a vasopressor agent of the anesthesiologist's armamentarium in the treatment of cardiac arrest and severe shock states.

Effects of sustained abdominal aorta compression on coronary perfusion pressures and restoration of spontaneous circulation during cardiopulmonary resuscitation in swine

OBJECTIVES

The present study was undertaken to explore whether sustained abdominal aorta compression-cardiopulmonary resuscitation (SAAC-CPR), as a means, can raise coronary perfusion pressure (CPP) as well as restoration of spontaneous circulation (ROSC) during CPR. In the present study, we hypothesised that SAAC-CPR elevates CPP during CPR and improves ROSC, without causing liver laceration.

METHODS

Animals were randomised into one of two groups (Standard CPR and SAAC-CPR). Ten domestic swine (22-25 kg) were anaesthetised, intubated and mechanically ventilated. Ventricular fibrillation was induced, and after 3 min of untreated ventricular fibrillation, the animals were treated with standard CPR (with simplex chest compression (SCC) and epinephrine) or SAAC-CPR (SCC with sustained abdominal aorta compression, without epinephrine). CPP and ROSC were compared.

RESULTS

SCC with sustained abdominal aorta compression (SCC+SAAC) significantly increased CPP in comparison with SCC during CPR (p<0.05). The increase in CPP with SCC+SAAC is equivalent to that achieved with epinephrine (p>0.05). All animals in the standard CPR and SAAC-CPR groups restored spontaneous circulation. No liver damage was found in post-mortem examinations of the swine subjects.

CONCLUSIONS

During CPR, non-invasive SAAC can rapidly and reversibly raise the CPP as much as can epinephrine and is especially suitable for out-of-hospital CPR.

Part 10: Pediatric basic and advanced life support: 2010 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

Note From the Writing Group: Throughout this article, the reader will notice combinations of superscripted letters and numbers (eg, “Family Presence During ResuscitationPeds-003”). These callouts are hyperlinked to evidence-based worksheets, which were used in the development of this article. An appendix of worksheets, applicable to this article, is located at the end of the text. The worksheets are available in PDF format and are open access.

Vasopressin versus epinephrine for out-of-hospital cardiopulmonary resuscitation

Clinical question

Does the use of vasopressin for adult patients suffering a non-traumatic, out-of-hospital cardiac arrest improve the rates of survival to hospital admission (and discharge) better than epinephrine?

Investigational vasopressin receptor modulators in the pipeline

The vasopressin system is complex and interacts with the central nervous, cardiovascular, renal, and hematological systems. Vasopressin plays an important role in the control of blood osmolarity and vascular tone, but is also involved in many other physiological events, which are mediated mainly via three types of vasopressin receptor: V1R, V2R, and V3R. V1R primarily mediate the vascular, and V2R the aquaretic, effects of vasopressin. Vasopressin may also interact with other receptors, like adrenergic and angiotensin-II receptors, or with distinct biological pathways, including those of nitric oxide and the K(ATP) channel. There are numerous clinical situations where vasopressin receptor modulators (agonists or antagonists) could be used. Currently, vasopressin and terlipressin are most commonly used to stimulate V1R in vasodilatory shock and cardiac arrest, while desmopressin, a synthetic analogue of vasopressin, acts on V2R; but new molecules are becoming available in the treatment of inappropriate antidiuretic hormone (ADH) secretion.

Vasopressin for in-hospital pediatric cardiac arrest: results from the American Heart Association National Registry of Cardiopulmonary Resuscitation

OBJECTIVE

To describe the landscape of vasopressin uses reported to the American Heart Association National Registry of cardiopulmonary resuscitation (CPR) and test the hypothesis that vasopressin use will be associated with improved return of a sustained circulation (ROSC) following in-hospital pediatric cardiac arrest.

DESIGN

Multicentered, national registry of in-hospital CPR.

SETTING

One hundred seventy-six North American Hospitals reporting to registry from October 1999 to November 2004.

PATIENTS

Totally, 1293 consecutive pediatric patients with pulseless cardiac arrest meeting criteria for analysis identified from a registry of all patients resuscitated for cardiac arrest. Inclusion criteria were age <18 years, chest compressions and/or defibrillation, in-hospital location, and documented resuscitation record.

INTERVENTIONS

None.

MEASUREMENTS AND OUTCOMES

Prearrest, event, cardiopulmonary resuscitation, and postresuscitation variables were collected. Primary outcome variable was ROSC >20 minutes. Secondary survival outcomes included 24 hour, discharge and favorable neurologic survival on hospital discharge. Descriptive, univariate, and multivariable analysis to evaluate the association of vasopressin with survival outcomes were performed.

RESULTS

Only 5% of patients received vasopressin in this review. Vasopressin was most often given in a pediatric hospital (57%) and in and intensive care setting (76.6%). Patients who were given vasopressin had longer arrest duration (median 37 minutes) vs. those who did not (24 minutes) (p = 0.004). In multivariate analysis, vasopressin was associated with worse ROSC but no difference in 24 hours or discharge survival.

CONCLUSION

Vasopressin was given infrequently in in-hospital cardiac arrest. It was most likely to be given in an intensive care setting, and in a pediatric hospital. Multivariate analysis shows an association with vasopressin use and worse ROSC.

Role of arginine vasopressin in the setting of cardiopulmonary resuscitation

Arginine vasopressin (AVP) constitutes an integral part of the neuroendocrine stress response during cardiac arrest. A strong correlation between endogenous AVP secretion and outcome from cardiac arrest has led to a number of experimental studies indicating a survival benefit of AVP compared to epinephrine. In the clinical setting, however, things are less clear. Although current data suggest that both epinephrine and AVP are equally effective to restore spontaneous circulation in out-of-hospital cardiac arrest, benefits of AVP in specific patient groups, e.g. those with asystolic cardiac arrest, have been shown. The latest international guidelines recommend AVP as an alternative vasopressor drug which may replace the first or second dosage of epinephrine in the treatment of pulseless arrest If the combined use of AVP and epinephrine is superior to epinephrine alone in terms of improved hospital admission and discharge rates this needs to be re-confirmed by the results of an ongoing multicenter trial.

The use of mice and rats as animal models for cardiopulmonary resuscitation research

Cardiopulmonary resuscitation (CPR) after the induction of cardiac arrest (CA) has been studied in mice and rats. The anatomical and physiological parameters of the cardiopulmonary system of these two species have been defined during experimental studies and are comparable with those of humans. Moreover, these animal models are more ethical to establish and are easier to manipulate, when compared with larger experimental animals. Accordingly, the effects of successful CPR on the function of vital organs, such as the brain, have been investigated because damage to these vital organs is of concern in CA survivors. Furthermore, the efficacy of several drugs, such as adrenaline (epinephrine), vasopressin and nitroglycerin, has been evaluated for use in CA in these small animal models. The purpose of these studies is not only to increase the rate of survival of CA victims, but also to improve their quality of life by reducing damage to their vital organs after CA and during CPR.

Developing alternative strategies for the treatment of traumatic haemorrhagic shock

PURPOSE OF REVIEW

The optimal strategy of stabilizing haemodynamic function in uncontrolled traumatic haemorrhagic shock states is unclear. Although fluid replacement is established in controlled haemorrhagic shock, its use in uncontrolled haemorrhagic shock is controversial, because it may worsen bleeding.

RECENT FINDINGS

In the refractory phase of severe haemorrhagic shock, arginine vasopressin has been shown to be beneficial in selected cases due to an increase in arterial blood pressure, shift of blood away from a subdiaphragmatic bleeding site towards the heart and brain, and decrease in fluid resuscitation requirements. Especially in patients with severe traumatic brain injury, rapid stabilization of cardiocirculatory function is essential to ensure adequate brain perfusion and thus to prevent neurological damage and to improve outcome. In addition, despite wide distribution of highly developed and professional emergency medical systems in western industrialized countries, survival chances of patients with uncontrolled traumatic haemorrhagic shock in the prehospital setting are still poor.

SUMMARY

A multicenter, randomized, controlled, international clinical trial is being initiated to assess the effects of arginine vasopressin (10 IU) vs. saline placebo in prehospital traumatic haemorrhagic shock patients, not responding to standard shock treatment, being managed by helicopter emergency medical services [vasopressin in traumatic haemorrhagic shock (VITRIS.at) study].

Vasopressin in pediatric shock and cardiac arrest

OBJECTIVE

To review the physiology and the published literature on the role of vasopressin in shock in children.

DATA SOURCE

We searched MEDLINE (1966-2007), EMBASE (1980-2007), and the Cochrane Library, using the terms vasopressin, terlipressin, and shock and synonyms or related terms for relevant studies in pediatrics. We searched the online ISRCTN-Current Controlled Trials registry for ongoing trials. We reviewed the reference lists of all identified studies and reviews as well as personal files to identify other published studies.

RESULTS

Beneficial effects have been reported in vasodilatory shock and asystolic cardiac arrest in adults. Solid evidence for vasopressin use in children is scant. Observational studies have reported an improvement in blood pressure and rapid weaning off catecholamines during administration of low-dose vasopressin. Dosing in children is extrapolated from adult studies.

CONCLUSIONS

Vasopressin offers promise in shock and cardiac arrest in children. However, in view of the limited experience with vasopressin, it should be used with caution. Results of a double-blind, randomized controlled trial in children with vasodilatory shock will be available soon.

Vasopressin and epinephrine in the treatment of cardiac arrest: an experimental study

BACKGROUND

Epinephrine remains the drug of choice for cardiopulmonary resuscitation. The aim of the present study is to assess whether the combination of vasopressin and epinephrine, given their different mechanisms of action, provides better results than epinephrine alone in cardiopulmonary resuscitation.

METHODS

Ventricular fibrillation was induced in 22 Landrace/Large-White piglets, which were left untreated for 8 minutes before attempted resuscitation with precordial compression, mechanical ventilation and electrical defibrillation. Animals were randomized into 2 groups during cardiopulmonary resuscitation: 11 animals who received saline as placebo (20 ml dilution, bolus) + epinephrine (0.02 mg/kg) (Epi group); and 11 animals who received vasopressin (0.4 IU/kg/20 ml dilution, bolus) + epinephrine (0.02 mg/kg) (Vaso-Epi group). Electrical defibrillation was attempted after 10 minutes of ventricular fibrillation.

RESULTS

Ten of 11 animals in the Vaso-Epi group restored spontaneous circulation in comparison to only 4 of 11 in the Epi group (p = 0.02). Aortic diastolic pressure, as well as, coronary perfusion pressure were significantly increased (p < 0.05) during cardiopulmonary resuscitation in the Vaso-Epi group.

CONCLUSION

The administration of vasopressin in combination with epinephrine during cardiopulmonary resuscitation results in a drastic improvement in the hemodynamic parameters necessary for the return of spontaneous circulation.

Arginine vasopressin during sinus rhythm: effects on haemodynamic variables, left anterior descending coronary artery cross sectional area and cardiac index, before and after inhibition of NO-synthase, in pigs

We have shown previously that arginine vasopressin (AVP) given during sinus rhythm increases mean arterial blood pressure (MAP) and left anterior descending (LAD) coronary artery cross sectional area. AVP was assumed to result in vasodilatation via activation of the endothelial nitric oxide system. The purpose of the present study was to assess the effects of AVP before and after NO-inhibition. Nine domestic pigs were instrumented for measurement of haemodynamic variables using micromanometer-tipped catheters, and measurement of LAD coronary artery cross sectional area employing intravascular ultrasound (IVUS). Haemodynamic variables, LAD coronary artery cross sectional area and cardiac output were measured at baseline, 90 s and 5, 15, and 30 min after AVP (0.4 U kg (-1) IV) before and after blockade of nitric oxide synthase with N(G)-nitro L-arginine methyl ester (L-NAME). Compared with baseline, AVP significantly increased MAP after 90 s (89+/-4 versus 160+/-5 mm Hg), increased LAD coronary artery cross sectional area (11.3+/-1 versus 11.8+/-1 mm(2)) and decreased cardiac index (138+/-6 versus 53+/-6 mL/min kg(-1)). After blockade of nitric oxide synthase, AVP significantly increased MAP after 90 s (135+/-4 versus 151+/-3 mm Hg), increased LAD coronary artery cross sectional area (8.7+/-1 versus 8.9+/-1 mm(2)), and significantly decreased cardiac index (95+/-6 versus 29+/-4 mL/min kg (-1)).

IMPLICATIONS

During sinus rhythm, AVP increased MAP and LAD coronary artery cross sectional area, but decreased cardiac index.

Recent advances and controversies in adult cardiopulmonary resuscitation

Since its introduction more than four and half decades ago, the science of cardiopulmonary resuscitation has been enriched with a significant amount of scientific evidence. This in turn has led to the birth of new evidence based guidelines for resuscitation published by the European Resuscitation Council and the American Heart Association in late 2005. This article aims to review the recent advances and controversies in the science of resuscitation.

Sustained abdominal compression during CPR raises coronary perfusion pressures as much as vasopressor drugs

OBJECTIVES

This study investigated sustained abdominal compression as a means to improve coronary perfusion pressure (CPP) during cardiopulmonary resuscitation (CPR) and compared the resulting CPP augmentation with that achieved using vasopressor drugs.

METHOD

During electrically induced ventricular fibrillation in anesthetized, 30kg juvenile pigs, Thumper CPR was supplemented at intervals either by constant abdominal compression at 100-500mmHg using an inflated contoured cuff or by the administration of vasopressor drugs (epinephrine, vasopressin, or glibenclamide). CPP before and after cuff inflation or drug administration was the end point.

RESULTS

Sustained abdominal compression at >200mmHg increases CPP during VF and otherwise standard CPR by 8-18mmHg. The effect persists over practical ranges of chest compression force and duty cycle and is similar to that achieved with vasopressor drugs. Constant abdominal compression also augments CPP after prior administration of epinephrine or vasopressin.

CONCLUSIONS

During CPR noninvasive abdominal compression with the inflatable contoured cuff rapidly elevates the CPP, sustains the elevated CPP as long as the device is inflated, and is immediately and controllably reversible upon device deflation. Physical control of peripheral vascular resistance during CPR by abdominal compression has some advantages over pharmacological manipulation and deserves serious reconsideration, now that the limitations of pressor drugs during CPR have become better understood, including post-resuscitation myocardial depression and the need for intravenous access.

In-hospital resuscitation

A recent world expert conference on resuscitation and emergency cardiac care led to evidence-based international guidelines for cardiopulmonary resuscitation (CPR). Several changes to CPR interventions were recommended, and will have to be implemented into clinical practice. The poor prognosis of patients who suffer in-hospital cardiac arrest may be improved with developments in CPR interventions. In the present review the most important changes recommended by the new CPR guidelines and the latest promising CPR investigations are described, focusing on their impact on in-hospital resuscitation.

Epinephrine, but not vasopressin, improves survival rates in an adult rabbit model of asphyxia cardiac arrest

Although vasopressin has been reported to be more effective than epinephrine for cardiopulmonary resuscitation in ventricular fibrillation animal models, its efficacy in asphyxia model remains controversy. The purpose of this study was to investigate the effectiveness of vasopressin vs epinephrine on restoration of spontaneous circulation (ROSC) in a rabbit model of asphyxia cardiac arrest. Cardiac arrest was induced by clamping endotracheal tube. After 5 minutes of basic life-support cardiopulmonary resuscitation, animals who had no ROSC were randomly assigned to receive either epinephrine alone (epinephrine group; 200 microg/kg) or vasopressin alone (vasopressin group; 0.8 U/kg). The coronary perfusion pressure (CPP) was calculated as the difference between the minimal diastolic aortic and simultaneously recorded right atrial pressure. Restoration of spontaneous circulation was defined as an unassisted pulse with a systolic arterial pressure of 60 mm Hg or higher for 5 minutes or longer. We induced arrest in 62 rabbits, 15 of whom had ROSC before drug administration and were excluded from analysis. The remaining 47 rabbits were randomized to epinephrine group (n = 24) and vasopressin group (n = 23). Before and after drug administration, CPP in epinephrine group increased significantly (from -4 +/- 4 to 36 +/- 9 mm Hg at peak value, P = .000), whereas CPP in vasopressin group increased only slightly (from 9 +/- 5 to 18 +/- 6 mm Hg at peak value, P = .20). After drug administration, 13 of 24 epinephrine rabbit had ROSC, and only 2 of 23 vasopressin rabbit had ROSC (P < .01). Consequently, we conclude that epinephrine, but not vasopressin, increases survival rates in this adult rabbit asphyxia model.

Beneficial effects of terlipressin in prolonged pediatric cardiopulmonary resuscitation: a case series

OBJECTIVE

Arginine vasopressin was found in experimental and clinical studies to have a beneficial effect in cardiopulmonary resuscitation. The American Heart Association 2000 guidelines recommended its use for adult ventricular fibrillation arrest, and the American Heart Association 2005 guidelines noted that it may replace the first or second epinephrine dose. There is little reported experience with arginine vasopressin in cardiopulmonary resuscitation of children. Terlipressin, a long-acting analog of arginine vasopressin, has recently emerged as a treatment for vasodilatory shock in both adults and in children, but evidence of its effectiveness in the pediatric setting is sparse. The objective of this retrospective study is to describe our experience in adding terlipressin to the conventional protocol in children with cardiac arrest.

DESIGN

Retrospective case series study.

SETTING

An 18-bed pediatric critical care department at a university-affiliated tertiary care children's hospital.

PATIENTS

Seven pediatric patients with asystole, aged 2 months to 5 yrs, who experienced eight episodes of refractory cardiac arrest and did not respond to conventional therapy.

INTERVENTIONS

Addition of terlipressin to epinephrine during cardiopulmonary resuscitation of children.

MEASUREMENTS AND MAIN RESULTS

Return of spontaneous circulation was monitored and achieved in six out of eight episodes of cardiac arrest. One patient died 12 hrs after return of spontaneous circulation, and four patients survived to discharge with no neurologic sequelae.

CONCLUSIONS

The combination of terlipressin to epinephrine during cardiopulmonary resuscitation may have a beneficial effect in children with cardiac arrest. More studies on this drug's safety and efficacy in this setting are mandated.

Vasopressors for cardiopulmonary resuscitation. Does pharmacological evidence support clinical practice?

Adrenaline (epinephrine) has been used for cardiopulmonary resuscitation (CPR) since 1896. The rationale behind its use is thought to be its alpha-adrenoceptor-mediated peripheral vasoconstriction, causing residual blood flow to be diverted to coronary and cerebral circulations. This protects these tissues from ischaemic damage and increases the likelihood of restoration of spontaneous circulation. Clinical trials have not demonstrated any benefit of adrenaline over placebo as an agent for resuscitation. Adrenaline has deleterious effects in the setting of resuscitation, predictable from its promiscuous pharmacological profile. This article discusses the relevant pharmacology of adrenaline in the context of CPR. Experimental and clinical evidences for the use of adrenaline and alternative vasopressor agents in resuscitation are given, and the properties of an ideal vasopressor are discussed.

Pharmacotherapy considerations in advanced cardiac life support

Cardiac arrest and sudden cardiac death remain major causes of mortality. Early intervention has been facilitated by emergency medical response systems and the development of training programs in basic life support and advanced cardiac life support (ACLS). Despite the implementation of these programs, the likelihood of a meaningful outcome in many life-threatening situations remains poor. Pharmacotherapy plays a role in the management of patients with cardiac arrest, with new guidelines for ACLS available in 2005 providing recommendations for the role of specific drug therapies. Epinephrine continues as a recommended means to facilitate defibrillation in patients with pulseless ventricular tachycardia or ventricular fibrillation; vasopressin is an alternative. Amiodarone is the primary antiarrhythmic drug that has been shown to be effective for facilitation of defibrillation in patients with pulseless ventricular tachycardia or fibrillation and is also used for the management of atrial fibrillation and hemodynamically stable ventricular tachycardia. Epinephrine and atropine are the primary agents used for the management of asystole and pulseless electrical activity. Treatment of electrolyte abnormalities, severe hypotension, pulmonary embolism, acute ischemic stroke, and toxicologic emergencies are important components of ACLS management. Selection of the appropriate drug, dose, and timing and route of administration are among the many challenges faced in this setting. Pharmacists who are properly educated and trained regarding the use of pharmacotherapy for patients requiring ACLS can help maximize the likelihood of positive patient outcomes.

Vasopressors are essential during cardiopulmonary resuscitation in rats: Is vasopressin superior to adrenaline?

BACKGROUND

Vasopressors are recommended for cardiopulmonary resuscitation (CPR) after cardiac arrest. In order to assess possible benefits regarding neurological recovery, vasopressin versus adrenaline and the combination of both was tested against placebo in a cardiac arrest model in rats.

METHODS

Under anaesthesia with halothane and N2O, cardiac arrest was initiated via transoesophageal electrical fibrillation. After 7 min of global ischaemia, CPR was performed by external chest compression combined with defibrillation. Animals were randomly assigned to three groups receiving adrenaline, vasopressin and a combination of both (n = 15 per group) versus placebo (n = 8). At 1, 3 and 7 days animals were tested according to a neurological deficit score (NDS). After 7 days of reperfusion, coronal brain sections were analysed by Nissl- and TUNEL-staining. Viable as well as TUNEL-positive neurons were counted in the hippocampal CA-1 sector. For statistical analysis, the log rank and the Kruskal-Wallis ANOVA test were used. All data are given as mean+/-S.D.; a p-value <0.05 was considered significant.

RESULTS

Mean arterial blood pressure (MAP) measured in the aorta did not differ between the vasopressor groups, whereas placebo animals had significantly lower levels. Survival to 7 days revealed significant differences between the placebo (n = 0/8) and all vasopressor groups (adrenaline, 10/15; adrenaline/vasopressin, 8/15; vasopressin, 12/15). Histological deficit scoring by quantitative analysis of the Nissl- and TUNEL-staining showed no difference in the amount of viable and apoptotic neurons in the vasopressin group (viable: 33+/-18; apoptotic: 63+/-23) versus the adrenaline group (viable: 21+/-12; apoptotic: 67+/-17) and the adrenaline/vasopressin group (viable: 31+/-26; apoptotic: 61+/-27). Neurological deficit scoring did not show any differences between the vasopressor groups.

CONCLUSION

Administration of arginine-vasopressin during CPR does not improve behavioural and cerebral histopathological outcome, compared to the use of adrenaline or the combination of both vasopressors, after cardiac arrest in rats.

[Utility of vasopressin in cardiopulmonary resuscitation]

Many vasopressants have been studied in cardiopulmonary resuscitation (CPR) to increase cerebral and coronary perfusion. Although there is a debate on the utility of epinephrine, this is the one that has been used historically, above all after verifying that other agents such as norepinephrine, metoxamine or phenylephrine, have not been shown to be more effective. Currently, due to the good experimental results, the use of vasopressin (ADH) in CPR is being evaluated. However there is little (only three studies) and debated evidence based on randomized clinical trials (norepinephrine or ADH) in humans. Once these are reviewed, it can be concluded: The results of the three randomized studies in humans obtain different results regarding the utility of ADH in cardiorespiratory arrest (CRA) secondary to ventricular fibrillation, electro-mechanical dissociation or asystole. More prospective studies are needed to know the role of ADH in prolonged CRA and in asystole, that may be the subgroups that can benefit the most from this drug. The neurological repercussion of a drug in the context of CRA should be evaluated before its inclusion in the CPR guides.

Evolving role of vasopressin in the treatment of cardiac arrest

Sudden cardiac arrest is a major public heath problem, affecting more than 450,000 individuals annually. Response time and the initiation of cardiopulmonary resuscitation (CPR) remain the most important factors determining successful revival. During resuscitation, sympathomimetics are given to enhance cerebral and coronary perfusion pressures in an attempt to achieve restoration of spontaneous circulation. Epinephrine has been the preferred vasopressor since the inception of advanced cardiac life support, although the lack of definitive evidence regarding its effectiveness has created much controversy surrounding its use, including the optimum dosage. Vasopressin is an alternative vasopressor that, when given at high doses, causes vasoconstriction by directly stimulating smooth muscle V1 receptors. The 2000 American Heart Association (AHA) guidelines commented that vasopressin is a reasonable first-line vasopressor in patients with ventricular fibrillation or pulseless ventricular tachycardia. Since release of those guidelines, additional human studies support an expanded role for vasopressin, whereas other studies cast doubt regarding its efficacy compared with epinephrine. The AHA recently released revised guidelines for CPR and emergency cardiovascular care. The consensus was that vasopressors should remain a part of pulseless sudden cardiac arrest management, with epinephrine 1 mg every 3-5 minutes being the recommended adrenergic of choice. In these revised guidelines, the role of vasopressin expanded beyond previous recommendations, despite the recommendation being downgraded to class indeterminate. The guidelines comment that one dose of vasopressin 40 U may replace the first or second dose of epinephrine in all pulseless sudden cardiac arrest scenarios, including asystole and pulseless electrical activity. A consistent theme with all vasopressors in sudden cardiac arrest is that additional studies are necessary to clearly document greater efficacy compared with no treatment. Further evaluation is warranted to better assess the role of vasopressin in asystolic sudden cardiac arrest, as well as its use with epinephrine, and to determine its optimal timing of administration and potential synergistic effects.

Usefulness of vasopressin administered with epinephrine during out-of-hospital cardiac arrest

Vasopressin administration has been suggested during cardiopulmonary resuscitation, and a previous clinical trial has suggested that vasopressin is most effective when administered with epinephrine. Adult subjects (n = 325) who received > or =1 dose of intravenous epinephrine during cardiopulmonary resuscitation for nontraumatic, out-of-hospital cardiac arrest were randomly assigned to receive 40 IU of vasopressin (n = 167) or placebo (n = 158) as soon as possible after the first dose of epinephrine. The rate of return of pulses was similar between the vasopressin and placebo groups (31% vs 30%), as was the presence of pulses at the emergency department (19% vs 23%). No subgroup appeared to be differentially affected, and no effect of vasopressin was evident after adjustment for other clinical variables. Additional open-label vasopressin was administered by a physician after the study drug for 19 subjects in the placebo group and 27 subjects in the vasopressin group. Results were similar if these subjects were excluded or were assigned to an actual drug received. Survival duration for subjects admitted to the hospital did not differ between groups. In conclusion, vasopressin administered with epinephrine does not increase the rate of return of spontaneous circulation.

Colon ischaemia and necrosis as a complication of prolonged but successful CPR

Survival after prolonged cardiopulmonary resuscitation (CPR) is often associated with neurological and other sequelae. We describe a patient who survived prolonged cardiac arrest due to ventricular fibrillation neurologically intact but suffered colon ischaemia and necrosis in the post-resuscitation period. Subtotal colectomy was performed. We wonder whether this complication was related to the use of vasopressin.

Vasopressin during cardiopulmonary resuscitation and different shock states: a review of the literature

Vasopressin administration may be a promising therapy in the management of various shock states. In laboratory models of cardiac arrest, vasopressin improved vital organ blood flow, cerebral oxygen delivery, the rate of return of spontaneous circulation, and neurological recovery compared with epinephrine (adrenaline). In a study of 1219 adult patients with cardiac arrest, the effects of vasopressin were similar to those of epinephrine in the management of ventricular fibrillation and pulseless electrical activity; however, vasopressin was superior to epinephrine in patients with asystole. Furthermore, vasopressin followed by epinephrine resulted in significantly higher rates of survival to hospital admission and hospital discharge. The current cardiopulmonary resuscitation guidelines recommend intravenous vasopressin 40 IU or epinephrine 1mg in adult patients refractory to electrical countershock. Several investigations have demonstrated that vasopressin can successfully stabilize hemodynamic variables in advanced vasodilatory shock. Use of vasopressin in vasodilatory shock should be guided by strict hemodynamic indications, such as hypotension despite norepinephrine (noradrenaline) dosages >0.5 mug/kg/min. Vasopressin must never be used as the sole vasopressor agent. In our institutional routine, a fixed vasopressin dosage of 0.067 IU/min (i.e. 100 IU/50 mL at 2 mL/h) is administered and mean arterial pressure is regulated by adjusting norepinephrine infusion. When norepinephrine dosages decrease to 0.2 microg/kg/min, vasopressin is withdrawn in small steps according to the response in mean arterial pressure. Vasopressin also improved short- and long-term survival in various porcine models of uncontrolled hemorrhagic shock. In the clinical setting, we observed positive effects of vasopressin in some patients with life-threatening hemorrhagic shock, which had no longer responded to adrenergic catecholamines and fluid resuscitation. Clinical employment of vasopressin during hemorrhagic shock is experimental at this point in time.