Intraaortic Balloon Pumping During Cardioplegic Arrest Preserves Lung Function in Patients With Chronic Obstructive Pulmonary Disease

Adjusted mortality of extracorporeal membrane oxygenation for acute myocardial infarction patients in cardiogenic shock

Cardiogenic shock (CS) is a common cause of death following acute myocardial infarction (MI). This study aimed to evaluate the adjusted mortality of venoarterial extracorporeal membrane oxygenation (VA-ECMO) with intra-aortic balloon counterpulsation (IABP) for patients with MI-CS. We included 300 MI patients selected from a multinational registry and categorized into VA-ECMO + IABP (N = 39) and no VA-ECMO (medical management ± IABP) (N = 261) groups. Both groups' 30-day and 1-year mortality were compared using the weighted Kaplan-Meier, propensity score, and inverse probability of treatment weighting methods. Adjusted incidences of 30-day (VA-ECMO + IABP vs No VA-ECMO, 77.7% vs 50.7; P = .083) and 1-year mortality (92.3% vs 84.8%; P = .223) along with propensity-adjusted and inverse probability of treatment weighting models in 30-day (hazard ratio [HR], 1.57; 95% confidence interval [CI], 0.92-2.77; P = .346 and HR, 1.44; 95% CI, 0.42-3.17; P = .452, respectively) and 1-year mortality (HR, 1.56; 95% CI, 0.95-2.56; P = .076 and HR, 1.33; 95% CI, 0.57-3.06; P = .51, respectively) did not differ between the groups. However, better survival benefit 30 days post-ECMO could be supposed (31.6% vs 83.4%; P = .022). Therefore, patients with MI-CS treated with IABP with additional VA-ECMO and those not supported with ECMO have comparable overall 30-day and 1-year mortality risks. However, VA-ECMO-supported survivors might have better long-term clinical outcomes.

Hemodynamic Effect of Pulsatile on Blood Flow Distribution with VA ECMO: A Numerical Study

The pulsatile properties of arterial flow and pressure have been thought to be important. Nevertheless, a gap still exists in the hemodynamic effect of pulsatile flow in improving blood flow distribution of veno-arterial extracorporeal membrane oxygenation (VA ECMO) supported by the circulatory system. The finite-element models, consisting of the aorta, VA ECMO, and intra-aortic balloon pump (IABP) are proposed for fluid-structure interaction calculation of the mechanical response. Group A is cardiogenic shock with 1.5 L/min of cardiac output. Group B is cardiogenic shock with VA ECMO. Group C is added to IABP based on Group B. The sum of the blood flow of cardiac output and VA ECMO remains constant at 4.5 L/min in Group B and Group C. With the recovery of the left ventricular, the flow of VA ECMO declines, and the effective blood of IABP increases. IABP plays the function of balancing blood flow between left arteria femoralis and right arteria femoralis compared with VA ECMO only. The difference of the equivalent energy pressure (dEEP) is crossed at 2.0 L/min to 1.5 L/min of VA ECMO. PPI’ (the revised pulse pressure index) with IABP is twice as much as without IABP. The intersection with two opposing blood generates the region of the aortic arch for the VA ECMO (Group B). In contrast to the VA ECMO, the blood intersection appears from the descending aorta to the renal artery with VA ECMO and IABP. The maximum time-averaged wall shear stress (TAWSS) of the renal artery is a significant difference with or not IABP (VA ECMO: 2.02 vs. 1.98 vs. 2.37 vs. 2.61 vs. 2.86 Pa; VA ECMO and IABP: 8.02 vs. 6.99 vs. 6.62 vs. 6.30 vs. 5.83 Pa). In conclusion, with the recovery of the left ventricle, the flow of VA ECMO declines and the effective blood of IABP increases. The difference between the equivalent energy pressure (EEP) and the surplus hemodynamic energy (SHE) indicates the loss of pulsation from the left ventricular to VA ECMO. 2.0 L/min to 1.5 L/min of VA ECMO showing a similar hemodynamic energy loss with the weak influence of IABP.

Outcomes of Venoarterial Extracorporeal Membrane Oxygenation Plus Intra-Aortic Balloon Pumping for Treatment of Acute Myocardial Infarction Complicated by Cardiogenic Shock

Background

Clinical outcomes of acute myocardial infarction complicated by cardiogenic shock remain poor with high in‐hospital mortality. Veno‐arterial extracorporeal membrane oxygenation (VA‐ECMO) has been widely used for patients with acute myocardial infarction complicated by cardiogenic shock refractory to conservative therapy, which is likely fatal without mechanical circulatory support. However, whether additional intra‐aortic balloon pumping (IABP) use during VA‐ECMO support improves clinical outcomes remains controversial. This study sought to investigate prognostic impact of the combined VA‐ECMO plus IABP treatment compared with VA‐ECMO alone.

Methods and Results

From the nationwide Japanese administrative case‐mix Diagnostic Procedure Combination (DPC), the JROAD (Japanese Registry of All Cardiac and Vascular Diseases)–DPC, we identified 3815 patients with acute myocardial infarction complicated by cardiogenic shock who underwent primary percutaneous coronary intervention and managed with VA‐ECMO. Of these, 2964 patients (77.7%) were managed with IABP (VA‐ECMO plus IABP), whereas 851 (22.3%) were managed without IABP (VA‐ECMO alone). We compared in‐hospital, 7‐day, and 30‐day mortality between the VA‐ECMO plus IABP versus the VA‐ECMO alone support. Patients managed with VA‐ECMO plus IABP demonstrated significantly lower in‐hospital, 7‐day, and 30‐day mortality than those managed with VA‐ECMO alone (adjusted odds ratios [95% CI] of 0.47 [95% CI, 0.38–0.59], 0.41 [95% CI, 0.33–0.51], and 0.30 [95% CI, 0.25–0.37], respectively). The findings were consistent in the propensity matching and inverse probability of treatment‐weighting models.

Conclusions

This large‐scale, nationwide study demonstrated that the combination of VA‐ECMO plus IABP support was associated with significantly lower mortality compared with VA‐ECMO support alone in patients presenting with acute myocardial infarction complicated by cardiogenic shock who underwent primary percutaneous coronary intervention.

Body Perfusion during Adult Cardiopulmonary Bypass is Improved by Pulsatile flow with Intra-Aortic Balloon Pump

Purpose

To evaluate if the use of an intra-aortic balloon pump (IABP) during cardioplegic arrest improves body perfusion.

Methods

158 coronary artery bypass graft (CABG) patients were randomized to linear cardiopulmonary bypass (CPB) (n=71, Group A) or automatic 80 bpm intra-aortic ballon pump (IABP) induced pulsatile CPB (n=87, Group B). We evaluated hemodynamic response by Swan-Ganz catheter, inflammation by cytokines, coagulation and fibrinolysis, transaminase, bilirubin, amylase, lactate and renal function (estimated glomerular filtration rate (eGFR), creatinine, and incidence of renal insufficiency and failure).

Results

IABP induced Surplus Hemodynamic Energy was 15.8±4.9 mmHg, with higher mean arterial pressure during cross-clamping (p=0.001), and lower indexed systemic vascular resistances during cross-clamping (p=0.001) and CPB discontinuation (p=0.034). IL-2 and IL-6 were lower, while IL-10 proved higher in Group B (p<0.05). Group B showed lower chest drainage (p<0.05), transfusions (p<0.05), INR (p<0.05), and AT-III (p=0.001), together with higher platelets, aPTT (p<0.05), fibrinogen (p<0.05) and D-dimer (p<0.05). Transaminases, bilirubin, amylase, lactate were lower in Group B (p<0.05); eGFR was better in Group B from ITU-arrival to 48 hours, both in preoperative kidney disease Stages 1–2 (p<0.03) and Stage 3 (p<0.05), resulting in lower creatinine from ITU-arrival to 48 hours (p<0.03). Incidence of renal insufficiency (p=0.004) and need for renal replacement therapy (p=0.044) was lower in Group B Stage 3. Group B PaO2/FiO2 and lung compliance improved from aortic declamping to the first day (p<0.003) with shorter intubation time (p=0.01).

Conclusion

Pulsatile flow by IABP improves whole-body perfusion during CPB.

Pressure-controlled mechanical ventilation is more advantageous in the follow-up of patients with chronic obstructive pulmonary disease after open heart surgery

OBJECTIVE

Cardiopulmonary bypass deteriorates pulmonary functions to a certain extent. Patients with chronic obstructive pulmonary disease (COPD) are associated with increased mortality and morbidity risks in the postoperative period of open-heart surgery. In this study we compared 2 different mechanical ventilation modes, pressure-controlled ventilation (PCV) and volume-controlled ventilation (VCV), in this particular patient population.

PATIENTS AND METHODS

Forty patients with severe COPD were assigned to 1 of 2 groups and enrolled to receive PCV or VCV in the postoperative period. Arterial blood gases, respiratory parameters, and intensive care unit and hospital stays were compared between the 2 groups.

RESULTS

Maximum airway pressure was higher in the VCV group. Pulmonary compliance was lower in the VCV group and minute ventilation was significantly lower in the group ventilated with PCV mode. The respiratory index was increased in the PCV group compared with the VCV group and with preoperative findings. Duration of mechanical ventilation was significantly shorter with PCV; however, intensive care unit and hospital stays did not differ.

CONCLUSION

There is not a single widely accepted and established mode of ventilation for patients with COPD undergoing open-heart surgery. Our modest experience indicated promising results with PCV mode; however, further studies are warranted.

Intraaortic counterpulsation during cardiopulmonary bypass impairs distal organ perfusion

BACKGROUND

Recent studies have focused on the use of fixed-rate intraaortic balloon pumping (IABP) during cardiopulmonary bypass (CPB) to achieve pulsatile flow. Because application of an IABP catheter may represent a functional obstruction within the descending aorta, we explored the effect of IABP-pulsed CPB-perfusion with special attention to perfusion above and below the IABP balloon.

METHODS

Sixteen animals received an IABP catheter that remained turned off position (NP group, n = 8) or was switched to an automatic mode of 80 beats/min during CPB (PP group, n = 8). Flow-data and pressure-data were obtained above and below the IABP balloon. Tissue perfusion was evaluated by microspheres.

RESULTS

IABP-pulsed CPB-perfusion, as assessed at 30 minutes on CPB, increased proximal mean aortic pressure (p < 0.05) and carotid artery blood flow (p < 0.001), but decreased distal mean aortic pressure (p < 0.001). The decrease of distal mean aortic pressure in the PP group was associated with a 75 % decrease (p < 0.001) of renal tissue perfusion. During nonpulsed perfusion the respective variables remained essentially unchanged compared with pre-CPB levels.

CONCLUSIONS

Using IABP as a surrogate to achieve pulsatile perfusion during CPB contributes significantly to lowered aortic pressure in the distal portion of aorta and impaired tissue perfusion of the kidneys. The results are focusing on effects that may contribute to organ dysfunction and acute kidney injury. Consequently, assessment of perfusion pressure distal to the balloon should be addressed whenever IABP is used during CPB.

The Effect of Pulsatile Cardiopulmonary Bypass on Lung Function in Elderly Patients

Purpose

Cardiopulmonary bypass is still a major cause of lung injury and delay in pulmonary recovery after cardiac surgery. Although it has been shown that pulsatile flow induced by intra-aortic balloon pumping is beneficial for preserving lung function, it is not clear if the same beneficial effect can be accomplished with pulsatile flow generated in the extracorporeal circuit. Therefore, we investigated the effect of pulsatile flow, produced by a centrifugal pump, on lung function in elderly patients.

Methods

Serial measurements of lung biomarkers Clara cell 16 kD protein, surfactant protein D, and elastase were performed on blood samples from 37 elderly patients (≥75 years) who underwent elective aortic valve replacement surgery with CPB, either with pulsatile perfusion or continuous perfusion. Pulmonary function was assessed by postoperative ventilation time, the arterial blood oxygenation (PaO2/FiO2), the alveolar-arterial oxygen gradient (Aa-O2 gradient) and the pulmonary vascular resistance indexed by body surface area (PVRi).

Results

There was no difference in lung function between both groups, as assessed by the postoperative ventilation time, the PaO2/FiO2 ratio, and the Aa-O2 gradient. The PVRi, however, was significantly lower in the pulsatile perfusion group 15 mins after the administration of protamine (p<0.05). The plasma concentrations of the lung biomarkers increased during surgery and peaked at 1 h ICU, there were however no differences between groups.

Conclusions

Pulsatile flow does not seem beneficial to postoperative lung function in elderly patients. Moreover, pulsatile flow does not affect lung function on a subclinical level as assessed by lung biomarkers.

The impact of intraaortic balloon counterpulsation on bypass graft flow in patients with peripheral ECMO

OBJECTIVE

Numerous reports have been performed to investigate the hemodynamic effects of intraaortic balloon pumping (IABP) and nonpulsatile circulatory extracorporeal membrane oxygenation (ECMO), but studies on its impact on coronary artery bypass graft flow during concomitant use of IABP and ECMO are lacking. The aim of this study was to assess the impact of additional IABP support on the degree of blood flow increase in bypass grafts in high-risk patients with nonpulsatile femoral venoarterial ECMO.

METHODS

In six emergency coronary artery bypass graft patients (mean age = 66.3 +/- 2.1 years, gender = five males and one female, ejection fraction = 25.0 +/- 3.0%) requiring mechanical circulatory support with ECMO hemodynamic parameters and bypass graft flows were measured with and without IABP counterpulsation. A transit time flowmeter was used for intraoperative graft flow and pulsatility index (PI) measurements. Patients provided their control values.

RESULTS

The average value of the mean arterial pressure recorded prior to IABP was 63.6 + 2.9 mmHg and during IABP support 67.8 + 2.9 mmHg (p < 0.0001). IABP augmented the mean bypass graft flow from 46.8 +/- 9.6 mL/min to 56.4 +/- 12.1 mL/min (p < 0.005), resulting in a 17% increase. The difference in the PI was not statistically significant (2.6 +/- 0.2 with IABP, 2.6 +/- 0.3 without IABP).

CONCLUSIONS

We conclude that IABP-induced pulsatility significantly improves coronary bypass graft flows during nonpulsatile peripheral ECMO.

Degree of risk related to procedures performed in conjunction with surgical myocardial revascularization in octogenarians

INTRODUCTION/OBJECTIVES

We determined the degree of risk produced by the association of other surgical procedures with surgical myocardial revascularization in octogenarian patients and identified the risk factors that best explain hospital mortality.

METHODS

This study was an observational analytical historical cohort study involving octogenarians operated on at our institution between January 1, 2000 and January 1, 2005. We stratified the objective population as follows: Group 1 comprised octogenarians revascularized without associated procedures, and Group 2 comprised octogenarians revascularized with associated procedures. Statistical analyses included the t test for independent samples and multiple logistic regression analysis. Significance was accepted with an alpha error of 5%.

RESULTS

Univariate analyses revealed the following clinical and statistically significant variables: hospital mortality (P=0.002), diabetes mellitus (P=0.017), preoperative endocarditis (P=0.001), cardiogenic shock (P=0.019), use of an intra-aortic balloon pump (P=0.026), preoperative risk score (Parsonnet), P<0.001, procedure associated with revascularization (P<0.001), medium number of affected coronary arteries (P<0.001), use of extracorporeal circulation (P<0.001), time of extracorporeal circulation (P<0.001), number of distal anastomoses (P=0.002), graft type (P<0.001), postoperative breathing support (P<0.001), stroke (P<0.001), infection (P=0.002), creatinine level (P=0.018), and quality of life score (P=0.050).

DISCUSSION/CONCLUSIONS

In octogenarian patients, the need for a procedure associated with surgical myocardial revascularization produces an absolute increase in hospital mortality risk of 45%. The variables that contributed to hospital mortality were preoperative endocarditis, preoperative cardiogenic shock, the use of extracorporeal circulation, the length of time of extracorporeal circulation, postoperative creatinine level, and postoperative need for prolonged respiratory support.

A Randomized Trial of Pulsatile Perfusion Using an Intra-Aortic Balloon Pump Versus Nonpulsatile Perfusion on Short-Term Changes in Kidney Function During Cardiopulmonary Bypass During Myocardial Reperfusion

BACKGROUND

Nonpulsatile perfusion during cardiopulmonary bypass can induce renal damage. We evaluated whether pulsatile perfusion using an intra-aortic balloon pump preserves renal function in patients undergoing myocardial revascularization.

STUDY DESIGN

Randomized controlled trial, nonmasked parallel-group design.

SETTING & PARTICIPANTS

100 patients undergoing preoperative perfusion using an intra-aortic balloon pump; 64 with baseline estimated glomerular filtration rate (eGFR) of 60 mL/min/1.73 m(2) or greater (>or=1 mL/s/1.73 m(2); stage 1 or 2) and 36 with eGFR of 30 to 59 mL/min/1.73 m(2) (0.5 to 0.98 mL/s/1.73 m(2); stage 3).

INTERVENTION

Patients were randomly assigned to nonpulsatile perfusion during cardiopulmonary bypass (group A) or automatic intra-aortic balloon pump-induced pulsatile perfusion during cardiopulmonary bypass (group B).

OUTCOMES & MEASUREMENTS

Renal function, daily diuresis, complications, serum lactate levels, and other biochemical indices at 24 and 48 hours.

RESULTS

GFR, adjusted for baseline eGFR, was 16 mL/min/1.73 m(2) [0.27 mL/s/1.73 m(2)] less in group A (58.1 mL/min/1.73 m(2); 95% confidence interval [CI], 56.1 to 60.1 mL/min/1.73 m(2) [0.97 mL/s/1.73 m(2); 95% CI, 0.94 to 1.0 mL/s/1.73 m(2)]) than in group B (74.0 mL/min/1.73 m(2); 95% CI, 72.0 to 76.1 mL/min/1.73 m(2) [1.23 mL/s/1.73 m(2); 95% CI, 1.20 to 1.27 mL/s/1.73 m(2)]; P < 0.001). Plasma lactate levels were +3.9 mg/dL (+0.43 mmol/L) higher in group A (19.5 mg/dL; 95% CI, 18.4 to 20.5 mg/dL [2.16 mmol/L; 95% CI, 2.04 to 2.28 mmol/L]) than in group B (16.7 mg/dL; 95% CI, 14.4 to 16.7 mg/dL [1.73 mmol/L; 95% CI, 1.60 to 1.85 mmol/L]; P < 0.001). No significant difference between the 2 groups was observed for 24-hour diuresis. Patients with eGFR stage 3 had a greater decrease in GFR and daily diuresis and greater increase in lactate levels than those with eGFR stages 1 to 2.

LIMITATIONS

Short-term change in kidney function as a surrogate outcome for "hard" clinical outcomes of mortality, morbidity, and length of hospitalization. Other limitations are short-term follow-up and absence of measurement of hemodynamic parameters or inflammatory mediators.

CONCLUSIONS

Use of automatic pulsatile intra-aortic balloon pumps during cardiopulmonary bypass is associated with better renal function during myocardial reperfusion. More studies are needed to verify the effects of pulsatile intra-aortic balloon pumps.