Vasopressor and Inotrope Use in Canadian Emergency Departments: Evidence Based Consensus Guidelines

A Clinical Review of Vasopressors in Emergency Medicine

BACKGROUND

Vasopressor medications raise blood pressure through vasoconstriction and are essential in reversing the hypotension seen in many critically ill patients. Previously, vasopressor administration was largely limited to continuous infusions through central venous access.

OBJECTIVES OF THE REVIEW

This review addresses the clinical use of vasopressors in various shock states, including practical considerations and innovations in vasopressor administration. The focus is on the clinical administration of vasopressors across a range of shock states, including hypovolemic, distributive, cardiogenic, and obstructive shock.

DISCUSSION

Criteria for starting vasopressors are not clearly defined, though early use may be beneficial. A number of physiologic factors affect the body's response to vasopressors, such as acidosis and adrenal insufficiency. Peripheral and push-dose administration of vasopressors are becoming more common. Distributive shock is characterized by inappropriate vasodilation and vasopressors play a crucial role in maintaining adequate blood pressure. The use of vasopressors is more controversial in hypovolemic shock, as the preferred treatment is correction of the volume deficit. Evidence for vasopressors is limited in cardiogenic shock. For obstructive shock, vasopressors can temporize a patient's blood pressure until definitive therapy can reverse the underlying cause.

CONCLUSION

Across the categories of shock states, norepinephrine has wide applicability and is a reasonable first-line agent for shock of uncertain etiology. Keeping a broad differential when hypotension is refractory to vasopressors may help to identify adjunctive treatments in physiologic states that impair vasopressor effectiveness. Peripheral administration of vasopressors is safe and facilitates early administration, which may help to improve outcomes in some shock states.

Adverse Events of Peripherally Administered Norepinephrine During Surgery: A Prospective Multicenter Study

BACKGROUND

Perioperative treatment of hypotension by intravenous administration of norepinephrine in a peripheral vein can lead to adverse events, for example, tissue necrosis. However, the incidence and severity of adverse events during perioperative administration are unknown.

METHODS

This was a prospective observational study conducted at 3 Swedish hospitals from 2019 to 2022. A total of 1004 patients undergoing surgery, who met the criteria for perioperative peripheral norepinephrine administration, were included. The infusion site was inspected regularly. If swelling or paleness of skin was detected, the infusion site was changed to a different peripheral line. Systolic blood pressure and pulse frequency were monitored during the infusion time and defined as adverse events at >220 mm Hg and <40 beats•min -1 . In case of adverse events, patients were observed for up to 48 hours. The primary outcome was prevalence of extravasation, defined as swelling around the infusion site. Secondary outcomes were all types of adverse events and associations between predefined clinical variables and risk of adverse events.

RESULTS

We observed 2.3% (95% confidence interval [CI], 1.4%-3.2%) extravasation of infusion and 0.9% (95% CI, 0.4%-1.7%) bradycardia. No cases of tissue necrosis or severe hypertension were detected. All adverse events had dissipated spontaneously within 48 hours. Proximal catheter placement was associated with more adverse events.

CONCLUSIONS

Extravasation of peripherally administrated norepinephrine in the perioperative period occurred at similar rates as in previous studies in critically ill patients. In our setting, where we regularly inspected the infusion site and shifted site in case of swelling or paleness of skin, we observed no case of severe adverse events. Given that severe adverse events were absent, the potential benefit of this preventive approach requires confirmation in a larger population.

International pharmacy survey of peripheral vasopressor infusions in critical care (INFUSE)

PURPOSE

The primary objective was to determine the proportion of hospitals that administered norepinephrine peripheral vasopressor infusions (PVIs) in critically ill adult patients. Secondary objectives were to describe how norepinephrine is used such as the maximum duration, infusion rate and concentration, and to determine the most common first-line PVI used by country.

MATERIALS AND METHODS

An international multi-centre cross-sectional survey study was conducted in adult intensive care units in Australia, US, UK, Canada, and Saudi Arabia.

RESULTS

Critical care pharmacists from 132 institutions responded to the survey. Norepinephrine PVIs were utilised in 86% of institutions (n = 113/132). The median maximum duration of norepinephrine PVIs was 24 h (IQR 24-24) (n = 57/113). The most common maximum norepinephrine PVI rate was between 11 and 20 μg/min (n = 16/113). The most common maximum norepinephrine PVI concentration was 16 μg/mL (n = 60/113). Half of the institutions had a preference to administer another PVI over norepinephrine as a first-line agent (n = 66/132). The most common alternative PVI used by country was: US (phenylephrine 41%, n = 37/90), Canada (dopamine 31%, n = 5/16), UK (metaraminol 82%, n = 9/11), and Australia (metaraminol 89%, n = 8/9).

CONCLUSIONS

There is variability in clinical practice regarding PVI administration in critically ill adult patients dependent on drug availability and local institutional recommendations.

Adverse effects related with norepinephrine through short peripheral venous access: Scoping review

Peripheral administration of norepinephrine is restricted due to the association of extravasation with tissue necrosis.

METHOD

Scoping review with the objective of describing the adverse effects related to the administration of norepinephrine through short peripheral venous access and the characteristics of drug administration in patients hospitalized in ICU, surgery, and emergency services.

RESULTS

12 studies with heterogeneous characteristics by size and type of population were included. The proportion of complications associated with peripheral norepinephrine administration was less than 12% in observational studies and it was less than 2% in those that used doses less than 0.13μg/kg/min, and concentrations less than 22.3μg/mL. The main associated complication was extravasation and there were no cases of tissue necrosis at the venipuncture site, some extravasation cases were treated with phentolamine, terbutaline or topical nitroglycerin. The drug administration time ranged between 1 and 528hours with a weighted mean of 2.78h.

CONCLUSION

The main adverse effect was extravasation, no additional complications occurred, phentolamine and terbutaline seem to be useful, and its availability is a necessity. It is essential for the nursing staff to carry out a close assessment and comprehensive care in patients receiving norepinephrine by peripheral route.

In Vivo Laser-Induced Vasoactive Microenvironmental Setting via a Stimuli-Responsive Microstructured Depot

A stimuli-responsive polymeric three-dimensional microstructured film (PTMF) is a 3D structure with an array of sealed chambers on its external surface. In this work, we demonstrate the use of PTMF as a laser-triggered stimulus-response system for local in vivo targeted blood vessels stimulation by vasoactive substances. The native vascular networks of the mouse mesentery were used as model tissues. Epinephrine and KCl were used as vasoactive agents that were sealed into individual chambers upon precipitation in the amount of pictograms. We demonstrated the method for non-damaged one-by-one chamber activation using a focused 532 nm laser light passed through biological tissues. To avoid laser-induced photothermal damage to biological tissues, the PTMF was functionalized with Nile Red dye, which effectively absorbs laser light. Chemically stimulated blood vessel fluctuations were analyzed using digital image processing methods. Hemodynamics changes were measured and visualized using the particle image velocimetry approach.

Preclinical studies of NOS inhibitor T1059 vasopressor activity on the models of acute hemorrhagic shock in rats and dogs

The development of new effective and safe vasopressors is one of the ways to increase the effectiveness of the treatment of hypotensive disorders, the severe forms of which remain a common cause of death in all countries of the world. Previously, we synthesized the original compound T1059, a selective inhibitor of eNOS/iNOS which has a pronounced vasoconstrictive effect. Here we show its vasopressor activity in models of the early stage of acute hemorrhagic shock in rats and dogs, as part of preclinical studies. The results indicate NOS inhibitor T1059 as a potent long-acting vasopressor. Its single parenteral administration in sufficiently safe doses (1/50–1/9 LD₁₀), caused in rats and dogs a rapid increase in vascular tone, accompanied by a prolonged hypertensive effect (within 90–120 min in rats, and within 115 min in dogs). The repeated administration of T1059 at low doses (1/3 of the first dose) made it possible to considerably (by at least 60 min) prolong a significant vasopressor effect. In all schemes, T1059 administration considerably inhibited the development of threatening cardiorespiratory disorders and significantly (p = 0.0026–0.0098) increased the short-term survival of experimental animals, formally extending the duration of the “golden hour” by 2 times. These data indicate that NOS inhibitors and, in particular, compound T1059, are able to create new opportunities in the treatment of hypotensive disorders, including the provision of assistance at the prehospital stage of treatment of such pathologies.

Safety and outcomes of short-term use of peripheral vasoactive infusions in critically ill paediatric population in the emergency department

Early restoration of oxygen delivery to end organs in paediatric patients experiencing shock states is critical to optimizing outcomes. However, obtaining central access in paediatric patients may be challenging in non-intensive care settings. There is limited literature on the use of peripheral vasoactive infusions in the initial resuscitation of paediatric patients in the emergency department. The aims of this study were to report the associated complications of peripheral vasoactive infusions and describe our local experience on its use. This was a single-centre, retrospective study on all paediatric patients who received peripheral vasoactive infusions at our paediatric emergency department from 2009 to 2016. 65 patients were included in this study. No patients had any local or regional complications. The mean patient age was 8.29 years old (± 5.99). The most frequent diagnosis was septic shock (45, 69.2%). Dopamine was the most used peripheral vasoactive agent (71.2%). The median time to central agents was 2 h (IQR 1–4). 16(24.2%) received multiple peripheral infusions. We reported no complications of peripheral vasoactive infusions. Its use could serve as a bridge till central access is obtained. Considerations on the use of multiple peripheral vasoactive infusions in the emergency department setting needs further research.

Current use of inotropes in circulatory shock

Background

Treatment decisions on critically ill patients with circulatory shock lack consensus. In an international survey, we aimed to evaluate the indications, current practice, and therapeutic goals of inotrope therapy in the treatment of patients with circulatory shock.

Methods

From November 2016 to April 2017, an anonymous web-based survey on the use of cardiovascular drugs was accessible to members of the European Society of Intensive Care Medicine (ESICM). A total of 14 questions focused on the profile of respondents, the triggering factors, first-line choice, dosing, timing, targets, additional treatment strategy, and suggested effect of inotropes. In addition, a group of 42 international ESICM experts was asked to formulate recommendations for the use of inotropes based on 11 questions.

Results

A total of 839 physicians from 82 countries responded. Dobutamine was the first-line inotrope in critically ill patients with acute heart failure for 84% of respondents. Two-thirds of respondents (66%) stated to use inotropes when there were persistent clinical signs of hypoperfusion or persistent hyperlactatemia despite a supposed adequate use of fluids and vasopressors, with (44%) or without (22%) the context of low left ventricular ejection fraction. Nearly half (44%) of respondents stated an adequate cardiac output as target for inotropic treatment. The experts agreed on 11 strong recommendations, all of which were based on excellent (> 90%) or good (81–90%) agreement. Recommendations include the indications for inotropes (septic and cardiogenic shock), the choice of drugs (dobutamine, not dopamine), the triggers (low cardiac output and clinical signs of hypoperfusion) and targets (adequate cardiac output) and stopping criteria (adverse effects and clinical improvement).

Conclusion

Inotrope use in critically ill patients is quite heterogeneous as self-reported by individual caregivers. Eleven strong recommendations on the indications, choice, triggers and targets for the use of inotropes are given by international experts. Future studies should focus on consistent indications for inotrope use and implementation into a guideline for circulatory shock that encompasses individualized targets and outcomes.

Optimizing the Early Resuscitation After Out-of-Hospital Cardiac Arrest

Resuscitation after out-of-hospital cardiac arrest can be one of the most challenging scenarios in acute-care medicine. The devastating effects of postcardiac arrest syndrome carry a substantial morbidity and mortality that persist long after return of spontaneous circulation. Management of these patients requires the clinician to simultaneously address multiple emergent priorities including the resuscitation of the patient and the efficient diagnosis and management of the underlying etiology. This review provides a concise evidence-based overview of the core concepts involved in the early postcardiac arrest resuscitation. It will highlight the components of an effective management strategy including addressing hemodynamic, oxygenation, and ventilation goals as well as carefully considering cardiac catheterization and targeted temperature management. An organized approach is paramount to providing effective care to patients in this vulnerable time period.

Expert statement for the management of hypovolemia in sepsis

Hypovolemia is frequent in patients with sepsis and may contribute to worse outcome. The management of these patients is impeded by the low quality of the evidence for many of the specific components of the care. In this paper, we discuss recent advances and controversies in this field and give expert statements for the management of hypovolemia in patients with sepsis including triggers and targets for fluid therapy and volumes and types of fluid to be given. Finally, we point to unanswered questions and suggest a roadmap for future research.

Common Sense Approach to Managing Sepsis

Sepsis results in many deaths, prolonged suffering among survivors and relatives, and high use of resources both in developed and developing countries. The updated Surviving Sepsis Campaign guidelines should aid clinicians in improving the identification and management of these patients, but many uncertainties remain because most of the guidance is based on low-quality evidence. This article discusses how to use some of the specific items of the guidelines together with a common-sense approach to aid clinical management of patients with sepsis while trying to balance the potential benefit and harm of the items.

Time delays associated with vasoactive medication preparation and delivery in simulated patients at risk of cardiac arrest

PURPOSE

To compare, quantify, and describe the time-delays associated with four common methods of adrenaline administration in the simulated setting of impending cardiac arrest.

METHODS

Using sham medication and a high-fidelity simulator, experienced Nurses prepared, then delivered, adrenaline by: i) bolus, ii) lower-concentration infusion iii) higher-concentration infusion, and iv) higher-concentration infusion plus carrier-line. We recorded medication preparation and delivery time, plus administration errors and self-reported competence.

RESULTS

Median total delay was i) 120s for bolus (95% CI 112-128s); ii) 179s for lower concentration infusion (95% CI 172-186s); iii) 296s for higher concentration infusion (95% CI 285-307s); and iv) 411s for higher concentration infusion plus carrier line (95% CI 399-423s). Time to prepare/deliver a bolus was less than any infusion (p<0.001). Time to prepare/deliver a lower-concentration infusion was less than either higher-concentration infusion (p<0.001). No substantial equipment failures or medication errors were observed. Participants reported high-competence. The majority of delay was from drug preparation not delivery.

CONCLUSIONS

We highlight potentially dangerous delays with administration of life-saving medications by all four methods. We should prioritize boluses, and focus on improving drug preparation times and human performance, more than drug delivery and equipment.

Vasopressors: Do they have any role in hemorrhagic shock?

The priority in the management of patients with traumatic hemorrhagic shock is to control the bleeding with simultaneous volume resuscitation to maintain adequate tissue perfusion. Fluid replacement remains the mainstay of initial resuscitation in hemorrhagic shock. Traditionally, vasopressors are contraindicated in the early management of hemorrhagic shock due to their deleterious consequences, although vasopressors may have a role in resuscitation when vasoplegic shock ensues and blood pressure cannot be maintained by fluids alone. Use of vasopressors is not recommended according to the Advanced Trauma Life SupportR management principles. The role of vasopressors remains controversial with no clear guidelines on the timing, type, and dose of these drugs in hemorrhagic shock. Among vasopressors, norepinephrine and vasopressin have been used in the majority of the trials, although not many studies compare the effect of these two on long-term survival in trauma patients. This article reviews the pathophysiology of hemorrhagic shock, adverse effects of fluid resuscitation, and the various experimental and clinical studies on the use of vasopressors in the early phase of resuscitation in hemorrhagic shock.