Paceport Swan-Ganz Data Collection Study

Montreal Heart Institute136 enrolled

Overview

RV dysfunction has been associated with increased mortality in the ICU and cardiac surgical patients. Thus, early identification of RV dysfunction at less severe stages will allow for earlier intervention and potentially better patient outcomes. However, so far, no studies have reported prospectively the prevalence of abnormal RV pressure waveform during cardiac surgery and in the ICU. Our primary hypothesis is that the prevalence of abnormal RV pressure waveform occurs in more than 50% of cardiac surgical patients throughout their hospitalization. Those patients with abnormal RV pressure waveform will be more prone to post-operative complications related to RV dysfunction and failure in the OR and ICU.

The pulmonary artery catheter (PAC) consists of an intravenous device placed in the pulmonary artery to measure cardiac output, pulmonary artery pressures (Richard C, 2011) as well as cardiac filling pressures. Since its initial presentation by Swan in 1970 (H J Swan, 1970), several modifications were made on the initial catheter now allowing continuous assessment of cardiac output, continuous monitoring of stroke volume (SV), systemic vascular resistance (SVR) and mixed venous saturation (SvO2) (Arora, 2014) (H J Swan, 1970) (Richard C, 2011). We intend to enhance current Swan-Ganz catheters with clinical decision support tools to early identify hemodynamically unstable states that can lead to further deterioration of the patient's health state. Right ventricular (RV) dysfunction is mostly associated to a decrease in contractility, right ventricular pressure overload or right ventricular volume overload (François Haddad, 2008). RV dysfunction can occur in several clinical scenarios in the intensive care unit (ICU) and operating room (OR): pulmonary embolism, acute respiratory distress syndrome (ARDS), septic shock, RV infarction, and in pulmonary hypertensive patients undergoing cardiac surgery (François Haddad, 2008). RV dysfunction has been associated with increased mortality in the ICU and cardiac surgical patients (André Y. Denault, 2006) (Denault AY B. J.-S., 2016). Thus, early identification of RV dysfunction at less severe stages will allow for earlier intervention and potentially better patient outcomes. Unfortunately, identifying which patients will develop RV dysfunction and then progress towards RV failure have proven difficult. One of the reasons for delaying the diagnosis of RV dysfunction could be the lack of uniform definition, especially in the perioperative period. Echocardiographic definitions of RV dysfunction have been described in previous studies: RV fractional area change (RVFAC) \< 35 %, tricuspid annular plane systolic excursion (TAPSE) \< 16 mm, tissue Doppler S wave velocity \<10 cm/s, RV ejection fraction (RVEF) \<45% and RV dilation have been related to RV dysfunction (Rudski LG, 2010). However, these echocardiographic indices cannot be continuously monitored and are insufficient in describing RV function. The diagnosis of fulminant RV failure is more easily recognized as a combination of echocardiographic measures, compromised hemodynamic measures and clinical presentation (Raymond M, 2019) (François Haddad, 2008) (Haddad F, 2009). RV dysfunction is inevitably associated with absolute or relative pulmonary hypertension because of the anatomic and physiological connection between the RV and pulmonary vascular system (Naeije R, 2014) (François Haddad, 2008). The gold standard for measuring pulmonary pressure is still the pulmonary artery catheter. However, RV output can initially be preserved despite of pulmonary hypertension (Denault AY C. M., 2006). It is therefore mandatory that early, objective, continuous, easily obtainable and subclinical indices of RV dysfunction are found and validated to initiate early treatment of this disease. Since 2002, Dr Denault's group at Montreal Heart Institute has been using continuous RV pressure waveform monitoring initially for the diagnosis of RV outflow tract obstruction (Denault A, 2014) and then for RV diastolic dysfunction evaluation (St-Pierre P, 2014) (Myriam Amsallem, 2016). Preliminary data based on a retrospective study on 259 patients found that 110 (42.5%) patients had abnormal RV gradients before cardiopulmonary bypass (CPB).Abnormal RV diastolic pressure gradient was associated with higher EuroSCORE II (2.29 \[1.10-4.78\] vs. 1.62 \[1.10-3.04\], p=0.041), higher incidence of RV diastolic dysfunction using echocardiography (45 % vs. 29 %, p=0.038), higher body mass index (BMI) (27.0 \[24.9-30.5\] vs. 28.9 \[25.5-32.5\], p=0.022), pulmonary hypertension (mean pulmonary artery pressure (MPAP) \> 25 mmHg) (37 % vs. 48 %, p=0.005) and lower pulmonary artery pulsatility index (PAPi) (1.59 \[1.19-2.09\] vs. 1.18 \[0.92-1.54\], p\<0.0001). Patients with abnormal RV gradient had more frequent difficult separation from CPB (32 % vs. 19 %, p=0.033) and more often received inhaled pulmonary vasodilator treatment before CPB (50 % vs. 74 %, p\<0.001). However, this was retrospective and limited to the pre-CPB period. In 2017, in a review article on RV failure in the ICU (Hrymak C, 2017), RV pressure waveform monitoring using the paceport of the pulmonary artery catheter was recommended as a simple method of monitoring RV function (Rubenfeld GD, 1999). However, no studies have reported prospectively the prevalence of abnormal RV pressure waveform during cardiac surgery and in the ICU.

Outcomes

Primary Outcomes

Proportion of abnormal diastolic RV waveforms before CPB, after CPB and in the ICU

Abnormal RV pressure waveform will be defined as a difference between the RV end-diastolic minus the early-diastolic pressure \> 4 mmHg and a RVdP/dt \< 400 mmHg.

Time frame: From thermodilution catheter insertion until 2 hours after ICU arrival

Secondary Outcomes

Proportion of patients with difficult and complex separation from cardiopulmonary bypass at the end of cardiac surgery

Difficult separation from cardiopulmonary bypass: instability requiring at least two different types of pharmacological agents (i.e., inotropes ± vasopressors ± inhaled agents) Complex separation from cardiopulmonary bypass: Hemodynamic instability requiring return on cardiopulmonary bypass or addition of mechanical support (intra-aortic balloon pump or extra-corporeal membrane oxygenator)

Time frame: From the discontinuation of cardiopulmonary bypass until ICU arrival after surgery, assessed up to 4 hours

Cumulative time of Persistent Organ Dysfunction or Death (TPOD) during the first 28 days after cardiac surgery

TPOD is a continuous variable representative of the burden of care and morbidity during the first 28 days following cardiac surgery and was chosen to circumvent issues arising for using other clinical endpoint such as ICU length of stay

Time frame: Up to 28 days or until hospital discharge

Incidence of deaths during hospitalisation

Death from any cause

Time frame: Up to 28 days or until hospital discharge

Incidence of acute kidney injury (AKI)

Acute kidney injury (AKI) according to KDIGO serum creatinine criteria: Stage 1: ≥50% or 27 umol/L increases in serum creatinine, Stage 2: ≥100% increase in serum creatinine, Stage 3 ≥200% increase in serum creatinine or an increase to a level of ≥254 umol/L or dialysis initiation.

Time frame: Up to 28 days or until hospital discharge

Incidence of major bleeding

Major bleeding is defined by the Bleeding Academic Research Consortium (BARC) as one of the following: • Perioperative intracranial bleeding within 48h • Reoperation after closure of sternotomy for the purpose of controlling bleeding • Transfusion of ≥5 units of whole blood of packed red blood cells within a 48 hours period • Chest tube output ≥2L within a 24 hours period

Time frame: Up to 28 days or until hospital discharge

Incidence of surgical reintervention for any reasons

Re-operation after the initial surgery for any cause

Time frame: Up to 28 days or until hospital discharge

Incidence of deep sternal wound infection or mediastinitis

Diagnosis of a deep incisional surgical site infection or mediastinitis by a surgeon or attending physician

Time frame: Up to 28 days or until hospital discharge

Incidence of delirium

Delirium is defined as an intensive care delirium screening checklist (ICDSC) score(18) of ≥4 in the week following surgery or positive result for the Confusion Assessment Method for the ICU (CAM-ICU).

Time frame: Up to 28 days or until hospital discharge

Incidence of stroke

Central neurologic deficit persisting longer than 72 hours

Time frame: Up to 28 days or until hospital discharge

Total duration of ICU stay in hours

Number of hours passed in the ICU

Time frame: Up to 28 days or until hospital discharg

Duration of vasopressor requirements (in hours)

Vasopressors include norepinephrine, epinephrine, dobutamine, vasopressin, phenylephrine, milrinone, isoproterenol and dopamine

Time frame: Up to 28 days or until hospital discharge

Up to 28 days or until hospital discharge

Number of days hospitalized from the day of surgery to discharge

Time frame: Up to 28 days or until hospital discharge

Duration of mechanical ventilation (in hours)

A duration of \>24 hours will be considered prolonged ventilation requirements.

Time frame: Up to 28 days or until hospital discharge

Incidence of major morbidity or mortality

Including death, prolonged ventilation, stroke, renal failure (Stage ≥2), deep sternal wound infection and reoperation for any reason.

Time frame: Up to 28 days or until hospital discharge

Right ventricular ejection fraction

Assessed by the American Society of Echocardiography guidelines