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Non-invasive indices of right ventricular afterload following lung resection
ORAL ABSTRACT PRESENTATIONS / Journal of Cardiothoracic and Vascular Anesthesia 31 (2017) S70–S85
120 minutes after end of surgery and the IniCrea value was calculated for each patient. Finally, the ΔCrea was divided in 4 groups depending on their change in SCr: A:(1,-0.3]; B: (-0.3,0]; C:(0,0.5]; D:(0.5,1]. Results: A total of 8030 patients (2834 women) with a mean age of 65.5 years (range, 18 to 94) were investigated, 1517 patients had an elevated IniCrea. Overall 2764 died within the observational period of 14 years. Mortality was lowest in patients within cohort B and highest in cohort D in the low IniCrea-group. For the high IniCreagroup mortality was nearly equal in patients within cohort A&B and highest in cohort D. Detailed results are shown in figure 1. Discussion: A slight decrease in SCr is the reaction to fluid supply and blood loss. In patients with a low IniCrea both, a profound decline and a rise in ΔCrea increases the risk of mortality. In patients with a high IniCrea a decline in ΔCrea does not seem to increase the risk of mortality, but even a slight increase of ΔCrea worsens the outcome. Our findings suggest that an increase of ΔCrea early after CPB is worse and may be a marker of diffuse organ injury. A renoprotective postoperative course in those is recommended.
REFERENCES: 1. Lassnigg A, et al.; JASN 2004;15:15971605. 2. Bernardi MH, et al.; BJA 2015;114:53-62.
S73
OP51, PP38 Non-invasive indices of right ventricular afterload following lung resection
Adam Glass1,2, P McCall1,2, A Arthur2, J Kinsella2, B Shelley1,2 1
Golden Jubilee National Hospital, Department of Anaesthesia, Clydebank, UK 2 University of Glasgow, Department of Anaesthesia, Pain and Critical Care Medicine, Glasgow, UK Introduction: Surgical resection of lung cancer offers the best chance of cure but is associated with post-operative dyspnoea and decrease in functional capacity. This decrease in functional capacity is poorly related to the change in lung function and may be influenced by post-operative cardiac dysfunction. Our group has shown that right ventricular (RV) ejection fraction falls following lung resection and we hypothesise that this change results, at least in part, from an increase in RV afterload. Previous studies have not demonstrated a consistent increase in pulmonary vascular resistance following resection although this measure overlooks changes in the pulsatile components of afterload. Pulmonary artery (PA) distensibility and PA acceleration time (PAAT) are non-invasive indices of afterload which assess the pulsatile components of afterload and may offer insight into RV loading conditions following lung resection. Distensibility is a measure of pulmonary artery stiffness and is related to compliance whereas PAAT is
S74
ORAL ABSTRACT PRESENTATIONS / Journal of Cardiothoracic and Vascular Anesthesia 31 (2017) S70–S85
associated wave reflections; both decrease in conditions of increased afterload.
Clinica Universidad de Navarra, Department of Anaesthesioloy and Intensive Care Unit, Pamplona, Navarra, Spain
Methods: With ethics approval, velocity encoded cardiac MRI of the main, right and left PA's was performed; pre-op, on postop day two (POD2) and two months on 27 patients undergoing lung resection by thoracotomy. Randomised and anonymised images were dual reported for PAAT and distensibility. PAAT is the time to peak flow (ms) and distensibility was calculated as (max–min PA area)/min PA area. Comparisons were made using independent samples or paired t-tests.
Introduction: Clinically significant postoperative pulmonary complications (PPCs) occur in 10% to 20% of patients after thoracic surgery.(1) Perioperative morbidity and mortality in thoracic surgery is a public health issue, due to its impact on short-and long-term survival and consumption of resources in health services.(2) Risk prediction scores help physicians to optimize individual perioperative management and provide them with an accurate method of stratifying patients by risk. Several scores have been developed and tested to improve stratification of mortality risk in thoracic surgery but few studies have dealt with pulmonary complication risks. The aim of our study was to derive a new predictive index for PPCs in pulmonary resection surgery in our population to identify high risk patients.
Results: The distribution of cardiac output was higher through the PA on the operative side than the non-operative side pre-op (p¼ 0.03) but higher in non-operative vessel on POD2 (po0.01) and at two months (po0.01). Operative vessel distensibility fell from pre-op on POD2 (p¼ 0.02) and at two months (p¼ 0.04); non-operative and main PA distensibility were unchanged throughout (p40.14). Distensibility was lower in the operative than non-operative vessels only at two months (p¼0.01). PAAT decreased in all vessels from pre-op to POD2 (po0.01 for all). Main and operative PAAT remained decreased from pre-op at two months (p¼ 0.02 and po0.01) whilst non-operative PAAT returned to baseline (p¼0.22) (Figure 1). PAAT was shorter in the operative than non-operative vessels on POD2 (po0.01) and at two months (p¼0.02). Discussion: The changes in distensibility and PAAT imply the RV is subject to increased afterload following lung resection. By two months the non-operative vessel appears to have adapted to the increased cardiac output showing no change in distensibility or PAAT whilst the operative vessel has decreased distensibility and PAAT despite receiving a lower cardiac output. This operative vessel afterload is reflected in the main PA as decreased PAAT. Further work is needed to investigate if the described changes in afterload worsen on exercise and contributes to the post-operative decrease in functional capacity.
Methods: It was a retrospective, observational multicentre study (13 Spanish hospitals) during a period of 6 months. All the adult consecutive patients who underwent pulmonary resection were included. A record of the PPCs defined, as the presence of any of the following: atelectasis; pneumonia; pulmonary embolism; respiratory failure; and need for supplemental oxygen at hospital discharge. We used the potential PPC predictor variables according to earlier studies. A logistic regression model was constructed based on the presence of a PPC as the dependent variable. Bivariate analysis was performed to identify the preoperative variables that were associated (P o0.05) with PPCs. Multivariate linear regression modelling, by backward stepwise selection (p o0.05), was performed to assess the adjusted associations of the variables with the occurrence of PPCs. AUROC was computed as a descriptive tool for measuring discrimination by the model. To perform an internal validation of the proposed score, we conducted bootstrapping with 1000 replications using biascorrected confidence intervals.
OP52, PP32
Results: The study included 559 patients, of whom 65 (11.6%) suffered PPCs. 359 patients had primary lung cancer, 25% had lung metastatic disease and 10% had non-oncological disease. We identified three statistically significant factors for predicting PPCs: age; smoking status; and predicted postoperative forced expiratory volume in 1 s (ppo FEV1%). Combining them into a simple risk score (Age (years) – ppoFEV1 (%) þ (50 if current smoker or 35 if ex-smoker)), we were able to obtain an AUROC of 0.74 (95% confidence interval 0.68 to 0.79). (Fig 1.) We selected a score of 30 as the optimal cut-off value (sensitivity 80% and specificity 61%). According to that, 63% of our cohort was successfully classified as high risk with a likelihood ratio of 2.02.
Respiratory complications prediction model
after
lung
resection:
María-José Yepes-Temiño, M Lillo, P Monedero, JR Perez Valdivieso
risk
Discussion: We used a more accurate score to predict the occurrence of PPCs in our cohort than the described previously in the literature.(3) It is based on age, smoking status and ppo FEV1s. We propose that our formula should be externally validated.
120 minutes after end of surgery and the IniCrea value was calculated for each patient. Finally, the ΔCrea was divided in 4 groups depending on their change in SCr: A:(1,-0.3]; B: (-0.3,0]; C:(0,0.5]; D:(0.5,1]. Results: A total of 8030 patients (2834 women) with a mean age of 65.5 years (range, 18 to 94) were investigated, 1517 patients had an elevated IniCrea. Overall 2764 died within the observational period of 14 years. Mortality was lowest in patients within cohort B and highest in cohort D in the low IniCrea-group. For the high IniCreagroup mortality was nearly equal in patients within cohort A&B and highest in cohort D. Detailed results are shown in figure 1. Discussion: A slight decrease in SCr is the reaction to fluid supply and blood loss. In patients with a low IniCrea both, a profound decline and a rise in ΔCrea increases the risk of mortality. In patients with a high IniCrea a decline in ΔCrea does not seem to increase the risk of mortality, but even a slight increase of ΔCrea worsens the outcome. Our findings suggest that an increase of ΔCrea early after CPB is worse and may be a marker of diffuse organ injury. A renoprotective postoperative course in those is recommended.
REFERENCES: 1. Lassnigg A, et al.; JASN 2004;15:15971605. 2. Bernardi MH, et al.; BJA 2015;114:53-62.
S73
OP51, PP38 Non-invasive indices of right ventricular afterload following lung resection
Adam Glass1,2, P McCall1,2, A Arthur2, J Kinsella2, B Shelley1,2 1
Golden Jubilee National Hospital, Department of Anaesthesia, Clydebank, UK 2 University of Glasgow, Department of Anaesthesia, Pain and Critical Care Medicine, Glasgow, UK Introduction: Surgical resection of lung cancer offers the best chance of cure but is associated with post-operative dyspnoea and decrease in functional capacity. This decrease in functional capacity is poorly related to the change in lung function and may be influenced by post-operative cardiac dysfunction. Our group has shown that right ventricular (RV) ejection fraction falls following lung resection and we hypothesise that this change results, at least in part, from an increase in RV afterload. Previous studies have not demonstrated a consistent increase in pulmonary vascular resistance following resection although this measure overlooks changes in the pulsatile components of afterload. Pulmonary artery (PA) distensibility and PA acceleration time (PAAT) are non-invasive indices of afterload which assess the pulsatile components of afterload and may offer insight into RV loading conditions following lung resection. Distensibility is a measure of pulmonary artery stiffness and is related to compliance whereas PAAT is
S74
ORAL ABSTRACT PRESENTATIONS / Journal of Cardiothoracic and Vascular Anesthesia 31 (2017) S70–S85
associated wave reflections; both decrease in conditions of increased afterload.
Clinica Universidad de Navarra, Department of Anaesthesioloy and Intensive Care Unit, Pamplona, Navarra, Spain
Methods: With ethics approval, velocity encoded cardiac MRI of the main, right and left PA's was performed; pre-op, on postop day two (POD2) and two months on 27 patients undergoing lung resection by thoracotomy. Randomised and anonymised images were dual reported for PAAT and distensibility. PAAT is the time to peak flow (ms) and distensibility was calculated as (max–min PA area)/min PA area. Comparisons were made using independent samples or paired t-tests.
Introduction: Clinically significant postoperative pulmonary complications (PPCs) occur in 10% to 20% of patients after thoracic surgery.(1) Perioperative morbidity and mortality in thoracic surgery is a public health issue, due to its impact on short-and long-term survival and consumption of resources in health services.(2) Risk prediction scores help physicians to optimize individual perioperative management and provide them with an accurate method of stratifying patients by risk. Several scores have been developed and tested to improve stratification of mortality risk in thoracic surgery but few studies have dealt with pulmonary complication risks. The aim of our study was to derive a new predictive index for PPCs in pulmonary resection surgery in our population to identify high risk patients.
Results: The distribution of cardiac output was higher through the PA on the operative side than the non-operative side pre-op (p¼ 0.03) but higher in non-operative vessel on POD2 (po0.01) and at two months (po0.01). Operative vessel distensibility fell from pre-op on POD2 (p¼ 0.02) and at two months (p¼ 0.04); non-operative and main PA distensibility were unchanged throughout (p40.14). Distensibility was lower in the operative than non-operative vessels only at two months (p¼0.01). PAAT decreased in all vessels from pre-op to POD2 (po0.01 for all). Main and operative PAAT remained decreased from pre-op at two months (p¼ 0.02 and po0.01) whilst non-operative PAAT returned to baseline (p¼0.22) (Figure 1). PAAT was shorter in the operative than non-operative vessels on POD2 (po0.01) and at two months (p¼0.02). Discussion: The changes in distensibility and PAAT imply the RV is subject to increased afterload following lung resection. By two months the non-operative vessel appears to have adapted to the increased cardiac output showing no change in distensibility or PAAT whilst the operative vessel has decreased distensibility and PAAT despite receiving a lower cardiac output. This operative vessel afterload is reflected in the main PA as decreased PAAT. Further work is needed to investigate if the described changes in afterload worsen on exercise and contributes to the post-operative decrease in functional capacity.
Methods: It was a retrospective, observational multicentre study (13 Spanish hospitals) during a period of 6 months. All the adult consecutive patients who underwent pulmonary resection were included. A record of the PPCs defined, as the presence of any of the following: atelectasis; pneumonia; pulmonary embolism; respiratory failure; and need for supplemental oxygen at hospital discharge. We used the potential PPC predictor variables according to earlier studies. A logistic regression model was constructed based on the presence of a PPC as the dependent variable. Bivariate analysis was performed to identify the preoperative variables that were associated (P o0.05) with PPCs. Multivariate linear regression modelling, by backward stepwise selection (p o0.05), was performed to assess the adjusted associations of the variables with the occurrence of PPCs. AUROC was computed as a descriptive tool for measuring discrimination by the model. To perform an internal validation of the proposed score, we conducted bootstrapping with 1000 replications using biascorrected confidence intervals.
OP52, PP32
Results: The study included 559 patients, of whom 65 (11.6%) suffered PPCs. 359 patients had primary lung cancer, 25% had lung metastatic disease and 10% had non-oncological disease. We identified three statistically significant factors for predicting PPCs: age; smoking status; and predicted postoperative forced expiratory volume in 1 s (ppo FEV1%). Combining them into a simple risk score (Age (years) – ppoFEV1 (%) þ (50 if current smoker or 35 if ex-smoker)), we were able to obtain an AUROC of 0.74 (95% confidence interval 0.68 to 0.79). (Fig 1.) We selected a score of 30 as the optimal cut-off value (sensitivity 80% and specificity 61%). According to that, 63% of our cohort was successfully classified as high risk with a likelihood ratio of 2.02.
Respiratory complications prediction model
after
lung
resection:
María-José Yepes-Temiño, M Lillo, P Monedero, JR Perez Valdivieso
risk
Discussion: We used a more accurate score to predict the occurrence of PPCs in our cohort than the described previously in the literature.(3) It is based on age, smoking status and ppo FEV1s. We propose that our formula should be externally validated.