High Pleural Pressure Prevents Alveolar Overdistension and Hemodynamic Collapse in Acute Respiratory Distress Syndrome with Class III Obesity. A Clinical Trial.

Rationale: Obesity is characterized by elevated pleural pressure (Ppl) and worsening atelectasis during mechanical ventilation in patients with acute respiratory distress syndrome (ARDS).Objectives: To determine the effects of a lung recruitment maneuver (LRM) in the presence of elevated Ppl on hemodynamics, left and right ventricular pressure, and pulmonary vascular resistance. We hypothesized that elevated Ppl protects the cardiovascular system against high airway pressure and prevents lung overdistension.Methods: First, an interventional crossover trial in adult subjects with ARDS and a body mass index ≥ 35 kg/m2 (n = 21) was performed to explore the hemodynamic consequences of the LRM. Second, cardiovascular function was studied during low and high positive end-expiratory pressure (PEEP) in a model of swine with ARDS and high Ppl (n = 9) versus healthy swine with normal Ppl (n = 6).Measurements and Main Results: Subjects with ARDS and obesity (body mass index = 57 ± 12 kg/m2) after LRM required an increase in PEEP of 8 (95% confidence interval [95% CI], 7-10) cm H2O above traditional ARDS Network settings to improve lung function, oxygenation and [Formula: see text]/[Formula: see text] matching, without impairment of hemodynamics or right heart function. ARDS swine with high Ppl demonstrated unchanged transmural left ventricular pressure and systemic blood pressure after the LRM protocol. Pulmonary arterial hypertension decreased (8 [95% CI, 13-4] mm Hg), as did vascular resistance (1.5 [95% CI, 2.2-0.9] Wood units) and transmural right ventricular pressure (10 [95% CI, 15-6] mm Hg) during exhalation. LRM and PEEP decreased pulmonary vascular resistance and normalized the [Formula: see text]/[Formula: see text] ratio.Conclusions: High airway pressure is required to recruit lung atelectasis in patients with ARDS and class III obesity but causes minimal overdistension. In addition, patients with ARDS and class III obesity hemodynamically tolerate LRM with high airway pressure.Clinical trial registered with www.clinicaltrials.gov (NCT02503241).

Acute Myocardial Infarction Complicated by Cardiogenic Shock: Analysis of the Position Statement From the European Society of Cardiology Acute Cardiovascular Care Association, With Perioperative Implications.

Effective management of cardiogenic shock (CS) is hampered by a lack of evidence-based information. This is a high-mortality condition, without clear, evidence-based guidelines for perioperative management, specifically-a lack of target endpoints for treatment (e.g.: mean arterial pressure or oxygenation), utility of regional care systems or the benefits of palliative care. The Acute Cardiovascular Care Association (ACCA) of the European Society of Cardiology (ESC) recently published a position statement that aimed to offer contemporary guidance on the diagnosis and treatment of acute myocardial infarction (AMI) complicated by CS. Herein, we review this complex clinical topic and review the ACCA statement on AMI associated with CS, with a focus on relevance to perioperative management.

Deficit Accumulation and Phenotype Assessments of Frailty Both Poorly Predict Duration of Hospitalization and Serious Complications after Noncardiac Surgery.

BACKGROUND: Frailty is associated with adverse postoperative outcomes, but it remains unclear which measure of frailty is best. This study compared two approaches: the Modified Frailty Index, which is a deficit accumulation model (number of accumulated deficits), and the Hopkins Frailty Score, which is a phenotype model (consisting of shrinking, weakness, exhaustion, slowness, and low physical activity). The primary aim was to compare the ability of each frailty score to predict prolonged hospitalization. Secondarily, the ability of each score to predict 30-day readmission and/or postoperative complications was compared. METHODS: This study prospectively enrolled adults presenting for preanesthesia evaluation before elective noncardiac surgery. The Hopkins Frailty Score and Modified Frailty Index were both determined. The ability of each frailty score to predict the primary outcome (prolonged hospitalization) was compared using a ratio of root-mean-square prediction errors from linear regression models. The ability of each score to predict the secondary outcome (readmission and complications) was compared using ratio of root-mean-square prediction errors from logistic regression models. RESULTS: The study included 1,042 patients. The frailty rates were 23% (Modified Frailty Index of 4 or higher) and 18% (Hopkins Frailty Score of 3 or higher). In total, 12.9% patients were readmitted or had postoperative complications. The error of the Modified Frailty Index and Hopkins Frailty Score in predicting the primary outcome was 2.5 (95% CI, 2.2, 2.9) and 2.6 (95% CI, 2.2, 3.0) days, respectively, and their ratio was 1.0 (95% CI, 1.0, 1.0), indicating similarly poor prediction. Similarly, the error of respective frailty scores in predicting the probability of secondary outcome was high, specifically 0.3 (95% CI, 0.3, 0.4) and 0.3 (95% CI, 0.3, 0.4), and their ratio was 1.00 (95% CI, 1.0, 1.0). CONCLUSIONS: The Modified Frailty Index and Hopkins Frailty Score were similarly poor predictors of perioperative risk. Further studies, with different frailty screening tools, are needed to identify the best method to measure perioperative frailty.

Acute heart failure after liver transplantation: A narrative review.

Acute heart failure (AHF) is an under recognized yet potentially lethal complication after liver transplantation (LT) surgery. The increase in incidence of liver transplantation amongst high-risk patients and the leniency in the criteria for transplantation, predisposes these patients to postoperative AHF and the antecedent morbidity and mortality. The inability of conventional preoperative cardiovascular testing to accurately identify patients at risk for post-LT AHF poses a considerable challenge to clinicians caring for these patients. Even if high-risk patients are identified, there is considerable ambiguity in the candidacy for transplantation as well as optimization strategies that could potentially prevent the development of AHF in the postoperative period. The intraoperative and postoperative management of patients who develop AHF is also challenging and requires a well-coordinated multidisciplinary approach. The use of mechanical circulatory support in patients with refractory heart failure has the potential to improve outcomes but its use in this complex patient population can be associated with significant complications and requires a stringent risk-benefit analysis on a case-by-case basis.

A lung rescue team improves survival in obesity with acute respiratory distress syndrome.

BACKGROUND: Limited data exist regarding ventilation in patients with class III obesity [body mass index (BMI) > 40 kg/m2] and acute respiratory distress syndrome (ARDS). The aim of the present study was to determine whether an individualized titration of mechanical ventilation according to cardiopulmonary physiology reduces the mortality in patients with class III obesity and ARDS. METHODS: In this retrospective study, we enrolled adults admitted to the ICU from 2012 to 2017 who had class III obesity and ARDS and received mechanical ventilation for > 48 h. Enrolled patients were divided in two cohorts: one cohort (2012-2014) had ventilator settings determined by the ARDSnet table for lower positive end-expiratory pressure/higher inspiratory fraction of oxygen (standard protocol-based cohort); the other cohort (2015-2017) had ventilator settings determined by an individualized protocol established by a lung rescue team (lung rescue team cohort). The lung rescue team used lung recruitment maneuvers, esophageal manometry, and hemodynamic monitoring. RESULTS: The standard protocol-based cohort included 70 patients (BMI = 49 ± 9 kg/m2), and the lung rescue team cohort included 50 patients (BMI = 54 ± 13 kg/m2). Patients in the standard protocol-based cohort compared to lung rescue team cohort had almost double the risk of dying at 28 days [31% versus 16%, P = 0.012; hazard ratio (HR) 0.32; 95% confidence interval (CI95%) 0.13-0.78] and 3 months (41% versus 22%, P = 0.006; HR 0.35; CI95% 0.16-0.74), and this effect persisted at 6 months and 1 year (incidence of death unchanged 41% versus 22%, P = 0.006; HR 0.35; CI95% 0.16-0.74). CONCLUSION: Individualized titration of mechanical ventilation by a lung rescue team was associated with decreased mortality compared to use of an ARDSnet table.

Systolic heart failure after liver transplantation: Incidence, predictors, and outcome.

Although most patients presenting for liver transplantation have normal left ventricular function, some develop left ventricular failure after transplantation. The primary objective of our study was to determine the predictors of systolic heart failure (HF) occurring immediately after liver transplantation. Its etiology, prospects of recovery, and factors associated with nonrecovery were also studied. Liver transplantations performed at our institution from January 2006 to February 2015 were evaluated using prospectively collected institutional registries. Patients with echocardiographically documented decline in ejection fraction to <45% within 6 months after liver transplantation were identified. Four controls were chosen per case: matched for age, gender, transplant year, and model for end-stage liver disease score. Conditional multivariable logistic regression was used for primary analysis and nonparametric tests for comparison between groups. In a cohort of 1284 adult patients, 45 cases and 180 controls were identified. Diastolic dysfunction (DD) was an independent predictor (OR 5.26, 95% CI 1.03-28.57, P = .04) of systolic HF in multivariable analysis. Stress-induced cardiomyopathy was the most common etiology. Left ventricular function recovered in 21 patients. Pretransplant DD decreased the chances of recovery (P = .05). In conclusion, patients with pretransplant DD need close post-transplant follow-up for timely identification of HF.

Reduced Left Ventricular Global Longitudinal Strain Predicts Prolonged Hospitalization: A Cohort Analysis of Patients Having Aortic Valve Replacement Surgery.

BACKGROUND: Left ventricular ejection fraction (LVEF) is often preserved in patients with aortic stenosis and thus cannot distinguish between normal myocardial contractile function and subclinical dysfunction. Global longitudinal strain and strain rate (SR), which measure myocardial deformation, are robust indicators of myocardial function and can detect subtle myocardial dysfunction that is not apparent with conventional echocardiographic measures. Strain and SR may better predict postoperative outcomes than LVEF. The primary aim of our investigation was to assess the association between global longitudinal strain and serious postoperative outcomes in patients with aortic stenosis having aortic valve replacement. Secondarily, we also assessed the associations between global longitudinal SR and LVEF and the outcomes. METHODS: In this post hoc analysis of data from a randomized clinical trial (NCT01187329), we examined the association between measures of myocardial function and the following outcomes: (1) need for postoperative inotropic/vasopressor support; (2) prolonged hospitalization (>7 days); and (3) postoperative atrial fibrillation. Standardized transesophageal echocardiographic examinations were performed after anesthetic induction. Myocardial deformation was measured using speckle-tracking echocardiography. Multivariable logistic regression was used to assess associations between measures of myocardial function and outcomes, adjusted for potential confounding factors. The predictive ability of global longitudinal strain, SR, and LVEF was assessed as area under receiver operating characteristics curves (AUCs). RESULTS: Of 100 patients enrolled in the clinical trial, 86 patients with aortic stenosis had acceptable images for global longitudinal strain analysis. Primarily, worse intraoperative global longitudinal strain was associated with prolonged hospitalization (odds ratio [98.3% confidence interval], 1.22 [1.01-1.47] per 1% decrease [absolute value] in strain; P = .012), but not with other outcomes. Secondarily, worse global longitudinal SR was associated with prolonged hospitalization (odds ratio [99.7% confidence interval], 1.68 [1.01-2.79] per 0.1 second(-1) decrease [absolute value] in SR; P = .003), but not other outcomes. LVEF was not associated with any outcomes. Global longitudinal SR was the best predictor for prolonged hospitalization (AUC, 0.72), followed by global longitudinal strain (AUC, 0.67) and LVEF (AUC, 0.62). CONCLUSIONS: Global longitudinal strain and SR are useful predictors of prolonged hospitalization in patients with aortic stenosis having an aortic valve replacement.

Transvenous Lead Extraction: A Clinical Commentary for Anesthesiologists.

With increasing use of cardiovascular implantable electronic devices, the need for lead extractions has increased to an annual volume of more than 10,000 extractions worldwide. This article provides a focused clinical commentary on the perioperative management, identification, and treatment of life-threatening complications associated with lead extractions. In addition, a summary of indications, techniques, and lead extraction complications is provided. Although uncommon, lead extractions are associated with a consistent rate of major procedure-related complications and mortality. Major life-threatening complications include vascular laceration, cardiac avulsion, hemothorax, pericardial effusion, and cardiac arrest. Comprehensive preoperative risk assessment and adequate planning and preparedness are crucial to decreasing all procedure-related adverse events. The location of the procedure (electrophysiology suite v hybrid operating room) and the nature of cardiac surgical backup are determined after meticulous risk stratification. In addition to decisions on vascular access, invasive monitoring, and modality of rhythm support, transesophageal echocardiography plays a crucial role in early diagnosis, timely management, and potential prevention of these complications.

Early Left and Right Ventricular Response to Aortic Valve Replacement.

BACKGROUND: The immediate effect of aortic valve replacement (AVR) for aortic stenosis on perioperative myocardial function is unclear. Left ventricular (LV) function may be impaired by cardioplegia-induced myocardial arrest and ischemia-reperfusion injury, especially in patients with LV hypertrophy. Alternatively, LV function may improve when afterload is reduced after AVR. The right ventricle (RV), however, experiences cardioplegic arrest without benefiting from improved loading conditions. Which of these effects on myocardial function dominate in patients undergoing AVR for aortic stenosis has not been thoroughly explored. Our primary objective is thus to characterize the effect of intraoperative events on LV function during AVR using echocardiographic measures of myocardial deformation. Second, we evaluated RV function. METHODS: In this supplementary analysis of 100 patients enrolled in a clinical trial (NCT01187329), 97 patients underwent AVR for aortic stenosis. Of these patients, 95 had a standardized intraoperative transesophageal echocardiographic examination of systolic and diastolic function performed before surgical incision and repeated after chest closure. Echocardiographic images were analyzed off-line for global longitudinal myocardial strain and strain rate using 2D speckle-tracking echocardiography. Myocardial deformation assessed at the beginning of surgery was compared with the end of surgery using paired t tests corrected for multiple comparisons. RESULTS: LV volumes and arterial blood pressure decreased, and heart rate increased at the end of surgery. Echocardiographic images were acceptable for analysis in 72 patients for LV strain, 67 for LV strain rate, and 54 for RV strain and strain rate. In 72 patients with LV strain images, 9 patients required epinephrine, 22 required norepinephrine, and 2 required both at the end of surgery. LV strain did not change at the end of surgery compared with the beginning of surgery (difference: 0.7 [97.6% confidence interval, -0.2 to 1.5]%; P = 0.07), whereas LV systolic strain rate improved (became more negative) (-0.3 [-0.4 to -0.2] s; P < 0.001). In contrast, RV systolic strain worsened (became less negative) at the end of surgery (difference: 4.6 [3.1 to 6.0]%; P < 0.001) although RV systolic strain rate was unchanged (0.0 [97.6% confidence interval, -0.1 to 0.1]; P = 0.83). CONCLUSIONS: LV function improved after replacement of a stenotic aortic valve demonstrated by improved longitudinal strain rate. In contrast, RV function, assessed by longitudinal strain, was reduced.

Use of colour Doppler and M-mode ultrasonography to confirm the location of an epidural catheter - a retrospective case series.

PURPOSE: Epidural anesthesia and analgesia has a reported failure rate ranging from 13% to 32%. We describe a technique using colour Doppler and M-mode ultrasonography to determine the position of the epidural catheter after placement in adults. METHODS: This retrospective review included 37 adult patients who received postoperative epidural analgesia and underwent technically difficult epidural catheter placement. The demographic characteristics, type of surgery, use of ultrasonography, method of insertion, intervertebral level, and success of epidural localization using colour Doppler were noted for each patient. Pain scores on postoperative day 1 and the presence of a patchy block were also reviewed. RESULTS: Colour Doppler study helped to indicate the catheter's path from the skin to the epidural space during saline injection in 33 patients (89%). Saline flow within the epidural space (catheter tip confirmation) was successfully detected with colour Doppler in 25 patients (67.5%) and with M-mode ultrasonography in 28 patients (75%). Appropriate dermatomal analgesia was noted in 35 patients (94.5%) during local anesthetic infusion. CONCLUSION: Our preliminary data suggest the feasibility of using colour Doppler and M-mode ultrasonography to confirm proper epidural catheter placement.

The response to Trendelenburg position is minimally affected by underlying hemodynamic conditions in patients with aortic stenosis.

PURPOSE: Trendelenburg positioning is commonly used to temporarily treat intraoperative hypotension. The Trendelenburg position improves cardiac output in normovolemic or anesthetized patients, but not hypovolemic or non-anesthetized patients. Therefore, the response to Trendelenburg positioning may vary depending on patient population or hemodynamic conditions. We thus tested the hypothesis that the effectiveness of the Trendelenburg position, as indicated by an increase in cardiac output, improves after replacement of a stenotic aortic valve. Secondarily, we evaluated whether measurements of left ventricular preload, systolic function, or afterload were associated with the response to Trendelenburg positioning. METHODS: This study is a secondary analysis of a clinical trial which included patients having aortic valve replacement (AVR) who were monitored with pulmonary artery catheters (NCT01187329). We examined changes in thermodilution cardiac output with Trendelenburg positioning before and after AVR. We also examined whether echocardiographic and hemodynamic measurements of preload, afterload, and systolic function were associated with changes in cardiac output during Trendelenburg positioning. RESULTS: Thirty-seven patients were included. The median [IQR] cardiac output change with Trendelenburg positioning was -3% [-10%, 5%] before AVR versus +4% [-4%, 15%] after AVR. Estimated median difference in cardiac output with Trendelenburg was 5% (95% CI 1, 15%, P = 0.04) greater after AVR. The response to Trendelenburg positioning was largely independent of hemodynamic conditions. CONCLUSION: The response to Trendelenburg positioning improved following AVR, but by a clinically unimportant amount. The response to Trendelenburg positioning was independent of hemodynamic conditions.

Localization of epidural space: A review of available technologies.

Although epidural analgesia is widely used for pain relief, it is associated with a significant failure rate. Loss of resistance technique, tactile feedback from the needle, and surface landmarks are traditionally used to guide the epidural needle tip into the epidural space (EDS). The aim of this narrative review is to critically appraise new and emerging technologies for identification of EDS and their potential role in the future. The PubMed, Cochrane Central Register of Controlled Clinical Studies, and Web of Science databases were searched using predecided search strategies, yielding 1048 results. After careful review of abstracts and full texts, 42 articles were selected to be included. Newer techniques for localization of EDS can be broadly classified into techniques that (1) guide the needle to the EDS, (2) identify needle entry into the EDS, and (3) confirm catheter location in EDS. An ideal method should be easy to learn and perform, easily reproducible with high sensitivity and specificity, identifies inadvertent intrathecal and intravascular catheter placements with ease, feasible in perioperative setting and have a cost-benefit advantage. Though none of them in their current stages of development qualify as an ideal method, many show tremendous potential. Some techniques are useful in patients with difficult spinal anatomy and infants, and thus are complementary to traditional methods. In addition to improving the existing technology, future research should aim at proving the superiority of these techniques over traditional methods, specifically regarding successful EDS localization, better safety profile, and a favorable cost-benefit ratio.

Impact and persistence of cirrhotic cardiomyopathy after liver transplantation.

Cirrhotic cardiomyopathy causes variable degree of systolic and diastolic dysfunction (DD) and conduction abnormalities. The primary aim of our study was to determine whether pre-transplant DD and prolonged corrected QT (QTc) predict a composite of mortality, graft failure, and major cardiovascular events after liver transplantation. We also evaluated the reversibility of cirrhotic cardiomyopathy after transplantation. Adult patients who underwent liver transplantation at our institution from January 2007 to March 2009 were included. Data were obtained from institutional registry, medical record review, and evaluation of echocardiographic images. Among 243 patients, 113 (46.5%) had grade 1 DD, 16 (6.6%) had grade 2 DD, and none had grade 3 DD. The mean pre-transplant QTc was 453 milliseconds. After a mean post-transplant follow-up of 5.2 years, 75 (31%) patients satisfied the primary composite outcome. Cox regression analysis did not show any significant association between DD and the composite outcome (P=.17). However, longer QTc was independently associated with the composite outcome (HR: 1.01, 95% confidence interval: 1.00-1.02, P=.05). DD (P<.001) and left ventricular mass index (P=.001) worsened after transplantation. In conclusion, QTc prolongation appears to be associated with worse outcomes. Although DD did not impact outcomes, it significantly worsened after transplantation.

Predictors of poor outcome among older liver transplant recipients.

With the increasing age of recipients undergoing orthotopic liver transplant (OLT), there is need for better risk stratification among them. Our study aims to identify predictors of poor outcome among OLT recipients ≥ 60 yr of age. All patients who underwent OLT at Cleveland Clinic from January 2004 to April 2010 were included. Baseline patient characteristics and post-OLT outcomes (mortality, graft failure, length of stay, and major post-OLT cardiovascular events) were obtained from prospectively collected institutional registry. Among patients ≥ 60 yr of age, multivariate regression modeling was performed to identify independent predictors of poor outcome. Of the 738 patients included, 223 (30.2%) were ≥ 60 yr. Hepatic encephalopathy, platelet counts < 45,000/µL, total serum bilirubin > 3.5 mg/dL, and serum albumin < 2.65 mg/dL independently predicted poor short-term outcomes. The presence of pre-OLT coronary artery disease and arrhythmia were independent predictors of poor long-term outcomes. Cardiac causes represented the second most common cause of mortality among the elderly cohort. Despite that, this carefully selected cohort of older OLT recipients had outcomes that were comparable with the younger recipients. Thus, our results show the need for better pre-OLT evaluation and optimization, and for closer post-OLT surveillance, of cardiovascular disease among the elderly.

Lack of association between carotid artery stenosis and stroke or myocardial injury after noncardiac surgery in high-risk patients.

BACKGROUND: Whether carotid artery stenosis predicts stroke after noncardiac surgery remains unknown. We therefore tested the primary hypothesis that degree of carotid artery stenosis is associated with in-hospital stroke or 30-day all-cause mortality after noncardiac surgery. As carotid artery stenosis is also a marker for cardiovascular disease, our secondary hypothesis was that degree of carotid artery stenosis is associated with postoperative myocardial injury. METHODS: We included adults who had noncardiac, noncarotid surgery at Cleveland Clinic from 2007 to 2011 and had carotid duplex ultrasound performed either within 6 months before or 1 month after surgery. Internal carotid artery peak systolic velocity (ICA PSV) was used as a measure of carotid artery stenosis severity. A multivariate (i.e., multiple outcomes per patient) generalized estimating equation model was used to assess the association between highest ICA PSV and the composite of stroke and 30-day mortality after adjusting for predefined potentially confounding variables. RESULTS: Of 2,110 patients included, 112 (5.3%) died within 30 days and 54 (2.6%) suffered postoperative in-hospital stroke. ICA PSV was not associated with this composite outcome (odds ratio of 1.0 [95% confidence interval: 0.99, 1.02] for a 10-unit increase, P = 0.55). ICA PSV was also not associated with postoperative myocardial injury (odds ratio 1.00 [0.99, 1.02], P = 0.49). CONCLUSIONS: This cohort represents a high-risk population, as carotid duplex examinations were likely prompted by neurological symptoms. There was nonetheless no association between carotid artery stenosis and perioperative stroke or 30-day mortality after noncardiac surgery.