Positive Pressure Ventilation in Cardiogenic Shock: Review of the Evidence and Practical Advice for Patients With Mechanical Circulatory Support

Cardiac power output ratio: Novel survival predictor after percutaneous ventricular assist device in cardiogenic shock

AIMS

Currently, there is limited data on prognostic indicators after insertion of percutaneous ventricular assist device (PVAD) in the treatment of cardiogenic shock (CS). This study evaluated the prognostic role of cardiac power output (CPO) ratio, defined as CPO at 24 h divided by early CPO (30 min to 2 h), in CS patients after PVAD.

METHODS AND RESULTS

Consecutive CS patients from the QEH-PVAD Registry were followed up for survival at 90 days after PVAD. Among 121 consecutive patients, 98 underwent right heart catheterization after PVAD, with CPO ratio available in 68 patients. The CPO ratio and 24-h CPO, but not the early CPO post PVAD, were significantly associated with 90-day survival, with corresponding area under curve in ROC analysis of 0.816, 0.740, and 0.469, respectively. In multivariate analysis, only the CPO ratio and lactate level at 24 h remained as independent survival predictors. The CPO ratio was not associated with age, sex, and body size. Patients with lower CPO ratio had significantly lower coronary perfusion pressure, worse right heart indices, and higher pulmonary vascular resistance. A lower CPO ratio was also significantly associated with mechanical ventilation and higher creatine kinase levels in myocardial infarction patients.

CONCLUSION

In post-PVAD patients, the CPO ratio outperformed the absolute CPO values and other haemodynamic metrics in predicting survival at 90 days. Such a proportional change of CPO over time, likely reflecting native heart function recovery, may help to guide management of CS patients post-PVAD.

Extra-cardiac management of cardiogenic shock in the intensive care unit

Cardiogenic shock (CS) is a heterogeneous clinical syndrome characterized by low cardiac output leading to end-organ hypoperfusion. Organ dysoxia ranging from transient organ injury to irreversible organ failure and death occurs across all CS etiologies but differing by incidence and type. Herein, we review the recognition and management of respiratory, renal and hepatic failure complicating CS. We also discuss unmet needs in the CS care pathway and future research priorities for generating evidence-based best practices for the management of extra-cardiac sequelae. The complexity of CS admitted to the contemporary cardiac intensive care unit demands a workforce skilled to care for these extra-cardiac critical illness complications with an appreciation for how cardio-systemic interactions influence critical illness outcomes in afflicted patients.

Invasive mechanical ventilation in cardiogenic shock complicating acute myocardial infarction: A contemporary Danish cohort analysis

PURPOSE

Invasive mechanical ventilation (IMV) is widely used in patients with cardiogenic shock following acute myocardial infarction (AMICS), but evidence to guide practice remains sparse. We sought to evaluate trends in the rate of IMV utilization, applied settings, and short term-outcome of a contemporary cohort of AMICS patients treated with IMV according to out-of-hospital cardiac arrest (OHCA) at admission.

METHODS

Consecutive AMICS patients receiving IMV in an intensive care unit (ICU) at two tertiary centres between 2010 and 2017. Data were analysed in relation to OHCA.

RESULTS

A total of 1274 mechanically ventilated AMICS patients were identified, 682 (54%) with OHCA. Frequency of IMV increased during the study period, primarily due to higher occurrence of OHCA admissions. Among 566 patients with complete ventilator data, positive-end-expiratory pressure, inspired oxygen fraction, and minute ventilation during the initial 24 h in ICU were monitored. No differences were observed between 30-day survivors and non-survivors with OHCA. In non-OHCA, these ventilator requirements were significantly higher among 30-day non-survivors (P for all<0.05), accompanied by a lower PaO2/FiO2 ratio (median 143 vs. 230, P < 0.001) and higher arterial lactate levels (median 3.5 vs. 1.5 mmol/L, P < 0.001) than survivors. Physiologically normal PaO2 and pCO2 levels were achieved in all patients irrespective of 30-day survival and OHCA status.

CONCLUSION

In the present contemporary cohort of AMICS patients, physiologically normal blood gas values were achieved both in OHCA and non-OHCA in the early phase of admission. However, increased demand of ventilatory support was associated with poorer survival only in non-OHCA patients.

The medical treatment of cardiogenic shock

Cardiogenic shock is characterized by tissue hypoperfusion due to the inadequate cardiac output to maintain the tissue oxygen demand. Despite some advances in cardiogenic shock management, extremely high mortality is still associated with this clinical syndrome. Its management is based on the immediate stabilization of hemodynamic parameters through medical care and the use of mechanical circulatory supports in specialized centers. This review aims to understand the cardiogenic shock current medical treatment, consisting mainly of inotropic drugs, vasopressors and coronary revascularization. In addition, we highlight the relevance of applying measures to other organ levels based on the optimization of mechanical ventilation and the appropriate initiation of renal replacement therapy.

The Management of Cardiogenic Shock From Diagnosis to Devices: A Narrative Review

Cardiogenic shock (CS) is a heterogenous syndrome broadly characterized by inadequate cardiac output leading to tissue hypoperfusion and multisystem organ dysfunction that carries an ongoing high mortality burden. The management of CS has advanced rapidly, especially with the incorporation of temporary mechanical circulatory support (tMCS) devices. A thorough understanding of how to approach a patient with CS and to select appropriate monitoring and treatment paradigms is essential in modern ICUs. Timely characterization of CS severity and hemodynamics is necessary to optimize outcomes, and this may be performed best by multidisciplinary shock-focused teams. In this article, we provide a review of CS aimed to inform both the cardiology-trained and non-cardiology-trained intensivist provider. We briefly describe the causes, pathophysiologic features, diagnosis, and severity staging of CS, focusing on gathering key information that is necessary for making management decisions. We go on to provide a more detailed review of CS management principles and practical applications, with a focus on tMCS. Medical management focuses on appropriate medication therapy to optimize perfusion-by enhancing contractility and minimizing afterload-and to facilitate decongestion. For more severe CS, or for patients with decompensating hemodynamic status despite medical therapy, initiation of the appropriate tMCS increasingly is common. We discuss the most common devices currently used for patients with CS-phenotyping patients as having left ventricular failure, right ventricular failure, or biventricular failure-and highlight key available data and particular points of consideration that inform tMCS device selection. Finally, we highlight core components of sedation and respiratory failure management for patients with CS.

Propofol vs etomidate for induction prior to invasive mechanical ventilation in patients with acute myocardial infarction

BACKGROUND

Patients with acute myocardial infarction (AMI) requiring invasive mechanical ventilation (IMV) have a high mortality. However, little is known regarding the impact of induction agents, used prior to IMV, on clinical outcomes in this population. We assessed for the association between induction agent and mortality in patients with AMI requiring IMV.

METHODS

We compared clinical outcomes between those receiving propofol compared to etomidate for induction among adults with AMI between October 2015 and December 2019 using the Vizient® Clinical Data Base, a multicenter, US national database. We used inverse probability treatment weighting (IPTW) to assess for the association between induction agent and in-hospital mortality.

RESULTS

We identified 5,147 patients, 1,386 (26.9%) of received propofol and 3,761 (73.1%) received etomidate for IMV induction. The mean (SD) age was 66.1 (12.4) years, 33.0% were women, and 51.6% and 39.8% presented with STEMI and cardiogenic shock, respectively. Patients in the propofol group were more likely to require preintubation vasoactive medication and mechanical circulatory support (both, P < .05). Utilization of propofol was associated with lower mortality compared to etomidate (32.3% vs 36.1%, P = .01). After propensity weighting, propofol use remained associated with lower mortality (weighted mean difference -4.7%; 95% confidence interval: -7.6% to -1.8%, P = .002). Total cost, ventilator days, and length of stay were higher in the propofol group (all, P < .001).

CONCLUSIONS

Induction with propofol, compared with etomidate, was associated with lower mortality for patients with AMI requiring IMV. Randomized trials are needed to determine the optimal induction agent for this critically ill patient population.

Complex Heart-Lung Ventilator Emergencies in the CICU

This review aims to enhance the comprehension and management of cardiopulmonary interactions in critically ill patients with cardiovascular disease undergoing mechanical ventilation. Highlighting the significance of maintaining a delicate balance, this article emphasizes the crucial role of adjusting ventilation parameters based on both invasive and noninvasive monitoring. It provides recommendations for the induction and liberation from mechanical ventilation. Special attention is given to the identification of auto-PEEP (positive end-expiratory pressure) and other situations that may impact hemodynamics and patients' outcomes.

Noninvasive Ventilation in the Cardiac Intensive Care Unit

Over the last several decades, the cardiac intensive care unit (CICU) has seen an increase in the complexity of the patient population and etiologies requiring CICU admission. Currently, respiratory failure is the most common reason for admission to the contemporary CICU. As a result, noninvasive ventilation (NIV), including noninvasive positive-pressure ventilation and high-flow nasal cannula, has been increasingly utilized in the management of patients admitted to the CICU. In this review, we detail the different NIV modalities and summarize the evidence supporting their use in conditions frequently encountered in the CICU. We describe the unique pathophysiologic interactions between positive pressure ventilation and left and/or right ventricular dysfunction. Additionally, we discuss the evidence and strategies for utilization of NIV as a method to reduce extubation failure in patients who required invasive mechanical ventilation. Lastly, we examine unique considerations for managing respiratory failure in certain, high-risk patient populations such as those with right ventricular failure, severe valvular disease, and adult congenital heart disease. Overall, it is critical for clinicians who practice in the CICU to be experts with the application, risks, benefits, and modalities of NIV in cardiac patients with respiratory failure.

DIFFERENCES IN MANAGEMENT AND PROGNOSTICATION OF CARDIOGENIC SHOCK PATIENTS IN THE PRESENCE AND ABSENCE OF OUT-OF-HOSPITAL CARDIAC ARREST

ABSTRACT

Background: The clinical spectrum of acute myocardial infarction complicated by cardiogenic shock (AMICS) varies. Out-of-hospital cardiac arrest (OHCA) can be the first sign of cardiac failure, whereas others present with various degrees of hemodynamic instability (non-OHCA). The aim of the present study was to explore differences in prehospital management and characteristics of survivors and nonsurvivors in AMICS patients with OHCA or non-OHCA. Methods: Data analysis was based on patient data from the RETROSHOCK cohort comprising consecutive AMICS patients admitted to two tertiary cardiac centers between 2010 and 2017. Results: 1,716 AMICS patients were included and 42% presented with OHCA. Mortality in OHCA patients was 47% versus 57% in the non-OHCA group. Almost all OHCA patients were intubated before admission (96%). In the non-OHCA group, prehospital intubation (25%) was associated with a better survival ( P < 0.001). Lactate level on admission demonstrated a linear relationship with mortality in OHCA patients. In non-OHCA, probability of death was higher for any given lactate level <12 mmol/L compared with OHCA. However, a lactate level >7 mmol/L in non-OHCA did not increase mortality odds any further. Conclusion: Mortality was almost doubled for any admission lactate level up to 7 mmol/L in non-OHCA patients. Above this level, mortality remained unchanged in non-OHCA patients but continued to increase in OHCA patients. Prehospital intubation was performed in almost all OHCA patients but only in one of four patients without OHCA. Early intubation in non-OHCA patients was associated with a better outcome.

In-hospital outcomes in unhoused patients with cardiogenic shock in the United States: Insights from The National Inpatient Sample 2011-2019

BACKGROUND

Unhoused patients face significant barriers to receiving health care in both the inpatient and outpatient settings. For unhoused patients with heart failure who are in extremis, there is a lack of data regarding in-hospital outcomes and resource utilization in the setting of cardiogenic shock (CS).

HYPOTHESIS

Unhoused patients hospitalized with CS have increased mortality and decreased use of invasive therapies as compared to housed patients.

METHODS

The National Inpatient Sample (NIS) database was queried from 2011 to 2019 for relevant ICD-9 and ICD-10 codes to identify unhoused patients with an admission diagnosis of CS. Baseline characteristics and in-hospital outcomes between patients were compared. Binary logistic regression was used to adjust outcomes for prespecified and significantly different baseline characteristics (p < .05).

RESULTS

We identified a weighted sample of 1 202 583 adult CS hospitalizations, of whom 4510 were unhoused (0.38%). There was no significant difference in the comorbidity adjusted odds of mortality between groups. Unhoused patients had lower odds of receiving mechanical circulatory support, left heart catheterization, percutaneous coronary intervention, or pulmonary artery catheterization. Unhoused patients had higher adjusted odds of infectious complications, undergoing intubation, or requiring restraints.

CONCLUSIONS

These data suggest that, despite having fewer traditional comorbidities, unhoused patients have similar mortality and less access to more aggressive care than housed patients. Unhoused patients may experience under-diuresis, or more conservative care strategies, as evidenced by the higher intubation rate in this population. Further studies are needed to elucidate long-term outcomes and investigate systemic methods to ameliorate barriers to care in unhoused populations.

Hyperoxia but not high tidal volume contributes to ventilator-induced lung injury in healthy mice

BACKGROUND

Mechanical ventilation is a supportive therapy used to maintain respiratory function in several clinical and surgical cases but is always accompanied by lung injury risk due to improper treatment. We investigated how tidal volume and oxygen delivery would contribute independently or synergistically to ventilator-induced lung injury (VILI).

METHODS

Under general anesthesia and tracheal intubation, healthy female C57BL/6 N mice (9 weeks old) were randomly ventilated for 2 h by standard (7 ml/kg) or high (14 ml/kg) tidal volume at positive end-expiratory pressure (PEEP) of 2 cmH2O, with room air, 50% O2 (moderate hyperoxia), or 100% O2 (severe hyperoxia); respectively. Mice were sacrificed 4 h after mechanical ventilation, and lung tissues were collected for experimental assessments on lung injury.

RESULTS

Compared with the healthy control, severe hyperoxia ventilation by either standard or high tidal volume resulted in significantly higher wet-to-dry lung weight ratio and higher levels of IL-1β and 8-OHdG in the lungs. However, moderate hyperoxia ventilation, even by high tidal volume did not significantly increase the levels of IL-1β and 8-OHdG in the lungs. Western blot analysis showed that the expression of RhoA, ROCK1, MLC2, and p-MLC2 was not significantly induced in the ventilated lungs, even by high tidal volume at 2 cmH2O PEEP.

CONCLUSION

Severe hyperoxia ventilation causes inflammatory response and oxidative damage in mechanically ventilated lungs, while high tidal volume ventilation at a reasonable PEEP possibly does not cause VILI.

Modifiable Mechanical Ventilation Targets Are Associated With Improved Survival in Ventilated VA-ECLS Patients

BACKGROUND

In acute respiratory distress syndrome (ARDS), lung protective ventilation (LPV) improves patient outcomes by minimizing ventilator-induced lung injury. The value of LPV in ventilated patients with cardiogenic shock (CS) requiring venoarterial extracorporeal life support (VA-ECLS) is not known, but the extracorporeal circuit provides a unique opportunity to modify ventilatory parameters to improve outcomes.

OBJECTIVES

The authors hypothesized that CS patients on VA-ECLS who require mechanical ventilation (MV) may benefit from low intrapulmonary pressure ventilation (LPPV), which has the same end goals as LPV.

METHODS

The authors queried the ELSO (Extracorporeal Life Support Organization) registry for hospital admissions between 2009 and 2019 for CS patients on VA-ECLS and MV. They defined LPPV as peak inspiratory pressure at 24 hours on ECLS of <30 cm H2O. Positive end-expiration pressure and dynamic driving pressure (DDP) at 24 hours were also studied as continuous variables. Their primary outcome was survival to discharge. Multivariable analyses were performed that adjusted for baseline Survival After Venoarterial Extracorporeal Membrane Oxygenation score, chronic lung conditions, and center extracorporeal membrane oxygenation volume.

RESULTS

A total of 2,226 CS patients on VA-ECLS were included: 1,904 received LPPV. The primary outcome was higher in the LPPV group vs the no-LPPV group (47.4% vs 32.6%; P < 0.001). Median peak inspiratory pressure (22 vs 24 cm H2O; P < 0.001) as well as DDP (14.5 vs 16 cm H2O; P < 0.001) were also significantly lower in those surviving to discharge. The adjusted OR for the primary outcome with LPPV was 1.69 (95% CI: 1.21-2.37; P = 0.0021).

CONCLUSIONS

LPPV is associated with improved outcomes in CS patients on VA-ECLS requiring MV.

Early Recognition and Risk Stratification in Cardiogenic Shock: Well Begun Is Half Done

Cardiogenic shock is a complex syndrome manifesting with distinct phenotypes depending on the severity of the primary cardiac insult and the underlying status. As long as therapeutic interventions fail to divert its unopposed rapid evolution, poor outcomes will continue challenging health care systems. Thus, early recognition in the emergency setting is a priority, in order to avoid delays in appropriate management and to ensure immediate initial stabilization. Since advanced therapeutic strategies and specialized shock centers may provide beneficial support, it seems that directing patients towards the recently described shock network may improve survival rates. A multidisciplinary approach strategy commands the interconnections between the strategic role of the ED in affiliation with cardiac shock centers. This review outlines critical features of early recognition and initial therapeutic management, as well as the utility of diagnostic tools and risk stratification models regarding the facilitation of patient trajectories through the shock network. Further, it proposes the implementation of precise criteria for shock team activation and the establishment of definite exclusion criteria for streaming the right patient to the right place at the right time.

Liberation From Mechanical Ventilation in the Cardiac Intensive Care Unit

The prevalence of respiratory failure is increasing in the contemporary cardiac intensive care unit (CICU) and is associated with a significant increase in morbidity and mortality. For patients that survive their initial respiratory decompensation, liberation from invasive mechanical ventilation (IMV) and the decision to extubate requires careful clinical assessment and planning. Therefore, it is essential for the CICU clinician to know how to assess and manage the various stages of IMV liberation, including ventilator weaning, evaluation of extubation readiness, and provide post-extubation care. In this review, we provide a comprehensive approach to liberation from IMV in the CICU, including cardiopulmonary interactions relative to withdrawal from positive pressure ventilation, evaluation of readiness for and assessment of spontaneous breathing trials, sedation management to optimize extubation, strategies for patients at a high risk for extubation failure, and tracheostomy in the cardiovascular patient.

Right ventricular function is associated with 28-day mortality in myocardial infarction complicated by cardiogenic shock: A retrospective observational study

Background

Right ventricular (RV) function is increasingly being recognised as an important factor influencing outcomes in ST elevation myocardial infarction (STEMI) complicated by cardiogenic shock (CS). In this study, we investigated RV echocardiographic parameters' association with 28-day mortality in patients admitted to intensive care with STEMI complicated by CS with reduced left ventricle ejection fraction (LVEF).

Method

We performed a retrospective analysis of patients admitted to intensive care unit (ICU) in a single tertiary cardiac centre over a 34-month period with STEMI complicated by CS and LVEF < 40%. Clinical and echocardiographic data were collected and correlated with 28-day mortality.

Results

One-hundred patients were included with a mean age of 62.6 ±12.7 years and 78% were male. Mortality at 28 days was 37%. Respectively, 85%, 40% and 25% of patients required mechanical ventilation, mechanical circulatory support and renal replacement therapy. Tricuspid annulus peak systolic velocity (RV S') was significantly higher in survivors (12 ± 3.3 v 10 ± 3.5 cm/s, p = 0.03) and was an independent predictor of mortality (odds ratio 1.2, 95% confidence interval 1.1-1.4, p = 0.04). RV S' of 10.5 cm/s exhibited best sensitivity and specificity (64% and 65%, respectively; p = 0.02) for mortality. The Kaplan-Meier curve demonstrated 85% risk of 28-day mortality for RV S' < 10.5 cm/s v 53% for RV S' > 10.5 cm/s (p = 0.02).

Conclusion

RV function is associated 28-day mortality in patients admitted to ICU with STEMI complicated by CS with reduced LVEF. RV S' predicted mortality with good sensitivity and specificity.

Intensive Care Management of the Cardiogenic Shock Patient

Optimal management of patients with cardiogenic shock requires a detailed and systematic assessment of all organ systems, balancing the risks and benefits of any investigation and intervention, while avoiding the complications of critical illness. Overall prognosis depends upon a number of factors, including that of the underlying cardiac disease and its potential reversibility, the severity of shock, the involvement of other organ systems, the age of the patient and comorbidities. As with all intensive care patients, the mainstay of management is supportive, up to and including implementation and management of a number of devices, including acute mechanical circulatory support. The assessment and management of these most critically ill patients therefore demands in-depth knowledge and skill relating to cardiac intensive care, extending well beyond standard intensive care or cardiology practice.

Basic mechanisms in cardiogenic shock: part 1-definition and pathophysiology

Cardiogenic shock mortality rates remain high despite significant advances in cardiovascular medicine and the widespread uptake of mechanical circulatory support systems. Except for early invasive angiography and percutaneous coronary intervention of the infarct-related artery, the most widely used therapeutic measures are based on low-quality evidence. The grim prognosis and lack of high-quality data warrant further action. Part 1 of this two-part educational review defines cardiogenic shock and discusses current treatment strategies. In addition, we summarize current knowledge on basic mechanisms in the pathophysiology of cardiogenic shock, focusing on inflammation and microvascular disturbances, which may ultimately be translated into diagnostic or therapeutic approaches to improve the outcome of our patients.

Optimal Perfusion Targets in Cardiogenic Shock

Cardiology shock is a syndrome of low cardiac output resulting in end-organ dysfunction. Few interventions have demonstrated meaningful clinical benefit, and cardiogenic shock continues to carry significant morbidity with mortality rates that have plateaued at upwards of 40% over the past decade. Clinicians must rely on clinical, biochemical, and hemodynamic parameters to guide resuscitation. Several features, including physical examination, renal function, serum lactate metabolism, venous oxygen saturation, and hemodynamic markers of right ventricular function, may be useful both as prognostic markers and to guide therapy. This article aims to review these targets, their utility in the care of patients with cardiology shock, and their association with outcomes.

Awake Implementation of Extracorporeal Life Support in Refractory Cardiogenic Shock

Background and objectives: Extracorporeal life support (ECLS) is a widely accepted and effective strategy for use in patients presenting with refractory cardiogenic shock. Implantation in awake and non-intubated patients allows for optimized evaluation of further therapy options while avoiding potential side effects associated with the need for sedation and intubation. The aim of the study was the assessment of safety and feasibility of awake ECLS implementation and of outcomes in patients treated with this concept. Materials and Methods: We retrospectively reviewed the concept of awake ECLS implantation in 16 consecutive patients (mean age 58 ± 8 years; male: 88%; ischemic cardiomyopathy: 50%) from 02/2017 to 01/2021. Study endpoints were survival to weaning or bridging to durable support or organ replacement and development of end-organ function and hemodynamic parameters on ECLS. Results: Fourteen patients (88%) were able to be successfully transitioned to definite therapy options. ECLS support stabilized end-organ function, led to a decrease in mean lactate levels (5.3 ± 3.7 mmol/L at baseline to 1.9 ± 1.3 mmol/L 12 h after ECLS start; p = 0.01) and improved hemodynamics (median central venous pressure 20 ± 5 mmHg vs. 10 ± 2 mmHg, p = 0.001) over a median duration of two days (1–8 days IQR). Two patients (13%) died on ECLS support due to multi-organ dysfunction syndrome. Survival to discharge of initially successfully bridged or weaned patients was 64%. Conclusions: Awake ECLS implantation is feasible and safe with the key advantage of omitting or delaying general anesthesia and intubation, with their associated risks in cardiogenic-shock patients, facilitating further decision making.

Ultrasound Assessment in Cardiogenic Shock Weaning: A Review of the State of the Art

Cardiogenic shock (CS) is associated with a high in-hospital mortality despite the achieved advances in diagnosis and management. Invasive mechanical ventilation and circulatory support constitute the highest step in cardiogenic shock therapy. Once established, taking the decision of weaning from such support is challenging. Intensive care unit (ICU) bedside echocardiography provides noninvasive, immediate, and low-cost monitoring of hemodynamic parameters such as cardiac output, filling pressure, structural disease, congestion status, and device functioning. Supplemented by an ultrasound of the lung and diaphragm, it is able to provide valuable information about signs suggesting a weaning failure. The aim of this article was to review the state of the art taking into account current evidence and knowledge on ICU bedside ultrasound for the evaluation of weaning from mechanical ventilation and circulatory support in cardiogenic shock.

Obstructive Sleep Apnea Syndrome Treated Using a Positive Pressure Ventilator Based on Artificial Intelligence Processor

With the acceleration of people's life rhythm, obstructive sleep apnea syndrome appears more and more frequently. This research mainly discusses the treatment of obstructive sleep apnea syndrome with a positive pressure ventilator based on artificial intelligence processor. The information storage function of the smart positive pressure ventilator is included in the local medical terminal, presented after logging in with the user authority. It is mainly composed of data collection, data processing, and medical interface design, which embeds data request, data transmission, data analysis, and detailed tasks such as data compression and storage, and functions such as data display, image drawing, and alarm notification are realized by the medical interface. When the CPAP ventilator transmits respiratory data to the local medical terminal, it sends real-time respiratory information data packets. The data packet is collected and sent in real time in a fixed period and then received and analyzed by the local medical terminal. In the CPAP ventilator telemedicine system, the function of alarm message processing is mainly used to detect the patient's breathing status in real time, extract the alarm-related information, and generate an alarm. This function specifically includes several tasks such as alarm detection, alarm prompt, alarm storage, and remote transmission of alarm messages. The confirmed OSAS patients were pressure-titrated with a smart CPAP ventilator and then treated for 5 hours a day, followed by echocardiography after 5 months of continuous treatment. During the study, the average BMI was (28.9 ± 7.2) kg/m2 and the average AHI index was (53.1 ± 37.8) times/h. This study may help improve the quality of life of patients with obstructive sleep apnea syndrome.

Mitral Regurgitation in Patients Undergoing Noncardiac Surgery

Mitral regurgitation (MR) is one of the most frequently encountered types of valvular heart disease in the United States. Patients with significant MR (moderate-to-severe or severe) undergoing noncardiac surgery have an increased risk of perioperative cardiovascular complications. MR can arise from a diverse array of causes that fall into 2 broad categories: primary (diseases intrinsic to the valvular apparatus) and secondary (diseases that disrupt normal valve function via effects on the left ventricle or mitral annulus). This article highlights key guideline updates from the American College of Cardiologists (ACC) and the American Heart Association (AHA) that inform decision-making for the anesthesiologist caring for a patient with MR undergoing noncardiac surgery. The pathophysiology and natural history of acute and chronic MR, staging of chronic primary and secondary MR, and considerations for timing of valvular corrective surgery are reviewed. These topics are then applied to a discussion of anesthetic management, including preoperative risk evaluation, anesthetic selection, hemodynamic goals, and intraoperative monitoring of the noncardiac surgical patient with MR.

Review of 20 Years of Continuous Quality Improvement of a Rapid Response System, at Four Institutions, to Identify Key Process Responsible for Its Success

BACKGROUND:

Rapid response systems are still in development, and their practices vary significantly from hospital to hospital. Although the literature supports their value and a four-arm structure, it is unclear within these arms (efferent, afferent, quality assurance, administrative arms) which processes and procedures are responsible for their efficacy. This article reports the evolution of a rapid response system over many years at four institutions and considers the key elements that likely contribute to its efficacy.

METHODS:

Retrospective evaluation of the processes, procedures, and outcomes of an adult general-ward rapid response system as it evolved, at four nonaffiliated community medical centers, spanning 2 decades of development and refinement. System and patient outcomes examined included the number of rapid response system activations/1,000 admissions, time to rapid response system activation and/or interventions, cardiac arrest rate, and/or hospital mortality over time.

RESULTS:

In the three hospitals that collected control and intervention data, there was significant increase in earlier and total number of rapid response system activations, more rapid administration of protocolized interventions, and associated decreases in cardiac arrest rate and hospital mortality of the respective population. In all four institutions three important common rapid response system processes were identified: early identification of at-risk patient using a novel focused bedside-assessment tool, leading to classification of the pathophysiologic process, linked to goal-directed intervention protocols.

CONCLUSIONS:

Our review of a rapid response system that evolved over 20 years across four unrelated institutions revealed a common care pathway that coupled a focused bedside at-risk patient assessment leading to pathophysiologic classification of the patients decline linked to goal-directed intervention protocols. We speculate that the improved outcomes observed are a consequence of effective implementation and coupling of these three processes, as they are important in identifying and treating early the signs of tissue hypoxia and hypoperfusion, which remain the basic pathophysiologic threats of acute deterioration.

Managing the first 120 min of cardiogenic shock: from resuscitation to diagnosis

PURPOSE OF REVIEW

Cardiogenic shock continues to carry a high mortality, and recent randomized trials have not identified novel therapies that improve survival. Early optimization of patients with confirmed or suspected cardiogenic shock is crucial, as patients can quickly transition from a hemodynamic shock state to a treatment-resistant hemometabolic shock state, where accumulated metabolic derangements trigger a self-perpetuating cycle of worsening shock.

RECENT FINDINGS

We describe a structured ABCDE approach involving stabilization of the airway, breathing and circulation, followed by damage control and etiologic assessment. Respiratory failure is common and many cardiogenic shock patients require invasive mechanical ventilation. Norepinephrine is titrated to restore mean arterial pressure and dobutamine is titrated to restore cardiac output and organ perfusion. Echocardiography is essential to identify potential causes and characterize the phenotype of cardiogenic shock. Coronary angiography is usually indicated, particularly when acute myocardial ischemia is suspected, followed by culprit-vessel revascularization if indicated. An invasive hemodynamic assessment can clarify whether temporary mechanical circulatory support is necessary.

SUMMARY

Early stabilization of hemodynamics and end-organ function is necessary to achieve best outcomes in cardiogenic shock. Using a structured approach tailored to initial cardiogenic shock resuscitation may help to demonstrate benefit from novel therapies in the future.

Mechanical Complications of Acute Myocardial Infarction: A Scientific Statement From the American Heart Association

Over the past few decades, advances in pharmacological, catheter-based, and surgical reperfusion have improved outcomes for patients with acute myocardial infarctions. However, patients with large infarcts or those who do not receive timely revascularization remain at risk for mechanical complications of acute myocardial infarction. The most commonly encountered mechanical complications are acute mitral regurgitation secondary to papillary muscle rupture, ventricular septal defect, pseudoaneurysm, and free wall rupture; each complication is associated with a significant risk of morbidity, mortality, and hospital resource utilization. The care for patients with mechanical complications is complex and requires a multidisciplinary collaboration for prompt recognition, diagnosis, hemodynamic stabilization, and decision support to assist patients and families in the selection of definitive therapies or palliation. However, because of the relatively small number of high-quality studies that exist to guide clinical practice, there is significant variability in care that mainly depends on local expertise and available resources.

Trends in Therapy and Outcomes Associated With Respiratory Failure in Patients Admitted to the Cardiac Intensive Care Unit

PURPOSE

To describe the epidemiology, outcomes, and temporal trends of respiratory failure in the cardiac intensive care unit (CICU).

MATERIALS AND METHODS

Retrospective cohort analysis of 2,986 unique Mayo Clinic CICU patients from 2007 to 2018 with respiratory failure. Temporal trends were analyzed, along with hospital and 1-year mortality. Multivariable logistic regression was used to determine adjusted hospital mortality trends.

RESULTS

The prevalence of respiratory failure in the CICU increased from 15% to 38% during the study period (P < 0.001 for trend). Among patients with respiratory failure, the utilization of invasive ventilation decreased and noninvasive ventilation modalities increased over time. Hospital mortality and 1-year mortality were 24% and 54%, respectively, with variation according to the type of respiratory support (highest among patients receiving invasive ventilation alone: 35% and 46%, respectively). Hospital mortality was highest among patients with concomitant cardiac arrest and/or shock (52% for patients with both). Hospital mortality decreased in the overall population from 35% to 25% (P < 0.001 for trend), but was unchanged among patients receiving positive-pressure ventilation.

CONCLUSIONS

The prevalence of respiratory failure in CICU more than doubled during the last decade. The use of noninvasive respiratory support increased, while overall mortality declined over time. Cardiac arrest and shock accounted for the majority of deaths. Further research is needed to optimize the outcomes of high-risk CICU patients with respiratory failure.