Echocardiography-Based Hemodynamic Management in the Cardiac Surgical Intensive Care Unit

Perioperative management in cardiovascular surgery

Cardio-surgical patient care requires a comprehensive and multidisciplinary approach to develop strategies to improve patient safety and outcomes. In the preoperative period, prophylaxis for frequent postoperative complications, such as de novo atrial fibrillation or bleeding, and prehabilitation based on exercise training, respiratory physiotherapy and nutritional and cognitive therapy, especially in fragile patients, stand out. There have been great advances, during the intraoperative phase, such as minimally invasive surgery, improved myocardial preservation, enhanced systemic perfusion and brain protection during extracorporeal circulation, or implementation of Safe Surgery protocols. Postoperative care should include goal-directed hemodynamic theraphy, a correct approach to coagulation disorders, and a multimodal analgesic protocol to facilitate early extubation and mobilization. Finally, optimal management of postoperative complications is key, including arrhythmias, vasoplegia, bleeding, and myocardial stunning that can lead to low cardiac output syndrome or, in extreme cases, cardiogenic shock. This global approach and the high degree of complexity require highly specialised units where intensive care specialists add value and are key to obtain more effective and efficient clinical results.

Echo is a good, not perfect, measure of cardiac output in critically ill surgical patients

BACKGROUND

Compared with a pulmonary artery catheter (PAC), transthoracic echocardiography (TTE) has been shown to have good agreement in cardiac output (CO) measurement in nonsurgical populations. Our hypothesis is that the feasibility and accuracy of CO measured by TTE (CO-TTE), relative to CO measured by PAC thermodilution (CO-PAC), is different in surgical intensive care unit patients (SP) and nonsurgical patients (NSP).

METHODS

Surgical patients with PAC for hemodynamic monitoring and NSP undergoing right heart catheterization were prospectively enrolled. Cardiac output was measured by CO-PAC and CO-TTE. Pearson coefficients were used to assess correlation. Bland-Altman analysis was used to determine agreement.

RESULTS

Over 18 months, 84 patients were enrolled (51 SP, 33 NSP). Cardiac output TTE could be measured in 65% (33/51) of SP versus 79% (26/33) of NSP; p = 0.17. Inability to measure the left ventricular outflow tract diameter was the primary reason for failure in both groups; 94% (17/18) in SP versus 86% (6/7) NSP; p = 0.47. Velocity time integral could be measured in all patients. In both groups, correlation between PAC and TTE measurement was strong; SP (r = 0.76; p < 0.0001), NSP (r = 0.86; p < 0.0001). Bland-Altman analysis demonstrated bias of -0.1 L/min, limits of agreement of -2.5 and +2.3 L/min, percentage error (PE) of 40% for SP, and bias of +0.4 L/min, limits of agreement of -1.8 and +2.5 L/min, and PE of 40% for NSP.

CONCLUSION

There was strong correlation and moderate agreement between TTE and PAC in both SP and NSP. In both patient populations, inability to measure the left ventricular outflow tract diameter was a limiting factor.

LEVEL OF EVIDENCE

Diagnostic tests or criteria, level III.

2019 EACTS Expert Consensus on long-term mechanical circulatory support

Long-term mechanical circulatory support (LT-MCS) is an important treatment modality for patients with severe heart failure. Different devices are available, and many-sometimes contradictory-observations regarding patient selection, surgical techniques, perioperative management and follow-up have been published. With the growing expertise in this field, the European Association for Cardio-Thoracic Surgery (EACTS) recognized a need for a structured multidisciplinary consensus about the approach to patients with LT-MCS. However, the evidence published so far is insufficient to allow for generation of meaningful guidelines complying with EACTS requirements. Instead, the EACTS presents an expert opinion in the LT-MCS field. This expert opinion addresses patient evaluation and preoperative optimization as well as management of cardiac and non-cardiac comorbidities. Further, extensive operative implantation techniques are summarized and evaluated by leading experts, depending on both patient characteristics and device selection. The faculty recognized that postoperative management is multidisciplinary and includes aspects of intensive care unit stay, rehabilitation, ambulatory care, myocardial recovery and end-of-life care and mirrored this fact in this paper. Additionally, the opinions of experts on diagnosis and management of adverse events including bleeding, cerebrovascular accidents and device malfunction are presented. In this expert consensus, the evidence for the complete management from patient selection to end-of-life care is carefully reviewed with the aim of guiding clinicians in optimizing management of patients considered for or supported by an LT-MCS device.

Postoperative Critical Care of the Adult Cardiac Surgical Patient. Part I: Routine Postoperative Care

OBJECTIVES

Cardiac surgery, including coronary artery bypass, cardiac valve, and aortic procedures, is among the most common surgical procedures performed in the United States. Successful outcomes after cardiac surgery depend on optimum postoperative critical care. The cardiac intensivist must have a comprehensive understanding of cardiopulmonary physiology and the sequelae of cardiopulmonary bypass. In this concise review, targeted at intensivists and surgeons, we discuss the routine management of the postoperative cardiac surgical patient.

DATA SOURCE AND SYNTHESIS

Narrative review of relevant English-language peer-reviewed medical literature.

CONCLUSIONS

Critical care of the cardiac surgical patient is a complex and dynamic endeavor. Adequate fluid resuscitation, appropriate inotropic support, attention to rewarming, and ventilator management are key components. Patient safety is enhanced by experienced personnel, a structured handover between the operating room and ICU teams, and appropriate transfusion strategies.

Feasibility and influence of hTEE monitoring on postoperative management in cardiac surgery patients

Monoplane hemodynamic TEE (hTEE) monitoring (ImaCor(®) ClariTEE(®)) might be a useful alternative to continuously evaluate cardiovascular function and we aimed to investigate the feasibility and influence of hTEE monitoring on postoperative management in cardiac surgery patients. After IRB approval we reviewed the electronic data of cardiac surgery patients admitted to our intensive care between 01/01/2012 and 30/06/2013 in a case-controlled matched-pairs design. Patients were eligible for the study when they presented a sustained hemodynamic instability postoperatively with the clinical need of an extended hemodynamic monitoring: (a) hTEE (hTEE group, n = 18), or (b) transpulmonary thermodilution (control group, n = 18). hTEE was performed by ICU residents after receiving an approximately 6-h hTEE training session. For hTEE guided hemodynamic optimization an institutional algorithm was used. The hTEE probe was blindly inserted at the first attempt in all patients and image quality was at least judged to be adequate. The frequency of hemodynamic examinations was higher (ten complete hTEE examinations every 2.6 h) in contrast to the control group (one examination every 8 h). hTEE findings, including five unexpected right heart failure and one pericardial tamponade, led to a change of current therapy in 89% of patients. The cumulative dose of epinephrine was significantly reduced (p = 0.034) and levosimendan administration was significantly increased (p = 0.047) in the hTEE group. hTEE was non-inferior to the control group in guiding norepinephrine treatment (p = 0.038). hTEE monitoring performed by ICU residents was feasible and beneficially influenced the postoperative management of cardiac surgery patients.

Initial clinical experience with a miniaturized transesophageal echocardiography probe in a cardiac intensive care unit

OBJECTIVE

To investigate the safety of a novel, miniaturized, monoplane transesophageal echocardiography probe (mTEE) and its potential as a hemodynamic monitoring tool.

DESIGN

This was a retrospective analysis of the clinical evaluation of a disposable mTEE in ventilated patients with severe cardiogenic shock requiring hemodynamic support. mTEE assessment was performed by operators with mixed levels of TEE training. Information on hemodynamic interventions based on mTEE findings was recorded.

SETTING

A tertiary university cardiac critical care unit.

PARTICIPANTS

Male and female critical care patients admitted to the unit with severe hemodynamic instability.

INTERVENTIONS

Insertion of miniaturized disposable TEE probe and hemodynamic and other critical care interventions based on this and conventional monitoring.

MEASUREMENTS AND MAIN RESULTS

In 41 patients (51.2% female, 73.2% after cardiac surgery), hemodynamic support probe insertion was accomplished without major complications. A total of 195 mTEE studies were performed, resulting in changes in therapy in 37 (90.2%) patients based on mTEE findings, leading to an improvement in hemodynamic parameters in 33 (80.5%) patients. Right ventricular (RV) failure was diagnosed in 25 patients (67.6%) and mTEE had a direct therapeutic impact on management of RV failure in 17 patients (68 %).

CONCLUSIONS

Insertion and operation of a novel, miniaturized transoesophageal echocardiography probe can be performed for up to 72 hours without major complications. Repeated assessment using this device provides complementary information to invasive monitoring in the majority of patients and has an impact on hemodynamic management.