Society of Thoracic Surgeons (STS): Annual Meeting

ORLANDO – A novel lung cancer screening program based in part on smoking-related meaningful use criteria proved feasible and was successful for identifying patients at a National Comprehensive Cancer Network cancer center who were eligible for screening.

The program, which was launched in January 2013, led to the screening of 110 patients and the detection and treatment of three stage I lung cancers during the first 7 months, Dr. Dan J. Raz of the City of Hope Medical Center in Duarte, Calif., reported at the annual meeting of the Society of Thoracic Surgeons.

©thinkstockphotos.com

During the first 3 months of the program, before the tobacco screen was developed, only four patients were enrolled – two by physician referral and two by self-referral. At that point, the tobacco screen was implemented, and 418 patients potentially eligible for screening were identified, Dr. Raz said.

The tobacco screen, which contained smoking-related meaningful use criteria established by the Centers for Medicare & Medicaid Services as part of the standards for electronic health records (EHRs), was easily implemented and took an average of less than 2 minutes to complete and enter into the EHR, he noted.

Pack-year calculations and quit dates for former smokers also were included in the tobacco screen.

The lung cancer screening program – known as the tobacco exposure program – was run by a nurse practitioner who also was a licensed tobacco dependency counselor. The tobacco screen was administered to all ambulatory adult patients every 6 months. Weekly electronic reports were generated to identify patients who met criteria for lung cancer screening eligibility.

Those who met the criteria, and who hadn’t undergone a chest or head computed tomography (CT) scan in the prior 12 months and who weren’t undergoing cancer treatment, were contacted to review the information. The primary treating physician also was contacted regarding the plan for lung cancer screening.

"Disappointingly, only 14% of those [identified as potentially eligible] enrolled," he said.

Of the 110 patients ultimately screened, 53% were identified using the tobacco screen, 29% were self-referred, and 18% were physician-referred.

About half of the 418 patients identified as potentially eligible couldn’t be reached by phone, and another third didn’t meet eligibility criteria or didn’t participate for another reason, but only 10 (2%) refused because of cost. The hospital discounted the cost of the CT to $150 for those without insurance coverage.

A comparison of the groups of patients who were self-referred, physician-referred, and identified using the tobacco screen showed that Asian patients, who made up 25% of the total patient population at the hospital, were underrepresented in the tobacco screen group, and those with a history of cancer comprised 82% of the group identified by the tobacco screen, Dr. Raz said. The former finding could be attributed to a language barrier, and the latter finding is not surprising given that the study hospital is a cancer center, Dr. Raz said.

"Lung cancer screening with low-dose radiation CT scans saves lives, it’s safe, and it’s cost effective. The U.S. Preventive Services Task Force recommends lung cancer screening, as do a number of other professional organizations, including the STS [Society of Thoracic Surgeons]," he said.

Still, it is believed that only a minority of those eligible undergo screening, he added, noting that a 2013 survey suggested that the median number of patients screened per year per lung cancer screening program is only 10.

The current findings suggest that augmenting meaningful use tobacco questions as part of a lung cancer screening program is feasible. This approach increased participation in the City of Hope Medical Center screening program.

"We think it’s a method that other centers can use or that primary care physicians can use to identify patients within their programs or within their systems," he said, noting that use of the tobacco screen also provides clinicians with an opportunity for smoking cessation intervention. In addition, the tobacco screen represents a useful research tool in that it systematically collects data on tobacco history.

As the "resource-consuming" nature of the program might be considered a limitation, efforts are underway to implement an automatic alert system based on the EHR to flag patients who meet lung cancer screening criteria and to automatically book a consultation. The program might also be improved by better outreach to non-English-speaking patients, and through systematic referral of high-risk patients, Dr. Raz said.

Dr. Raz reported having no disclosures.

ORLANDO – A novel lung cancer screening program based in part on smoking-related meaningful use criteria proved feasible and was successful for identifying patients at a National Comprehensive Cancer Network cancer center who were eligible for screening.

The program, which was launched in January 2013, led to the screening of 110 patients and the detection and treatment of three stage I lung cancers during the first 7 months, Dr. Dan J. Raz of the City of Hope Medical Center in Duarte, Calif., reported at the annual meeting of the Society of Thoracic Surgeons.

©thinkstockphotos.com

During the first 3 months of the program, before the tobacco screen was developed, only four patients were enrolled – two by physician referral and two by self-referral. At that point, the tobacco screen was implemented, and 418 patients potentially eligible for screening were identified, Dr. Raz said.

The tobacco screen, which contained smoking-related meaningful use criteria established by the Centers for Medicare & Medicaid Services as part of the standards for electronic health records (EHRs), was easily implemented and took an average of less than 2 minutes to complete and enter into the EHR, he noted.

Pack-year calculations and quit dates for former smokers also were included in the tobacco screen.

The lung cancer screening program – known as the tobacco exposure program – was run by a nurse practitioner who also was a licensed tobacco dependency counselor. The tobacco screen was administered to all ambulatory adult patients every 6 months. Weekly electronic reports were generated to identify patients who met criteria for lung cancer screening eligibility.

Those who met the criteria, and who hadn’t undergone a chest or head computed tomography (CT) scan in the prior 12 months and who weren’t undergoing cancer treatment, were contacted to review the information. The primary treating physician also was contacted regarding the plan for lung cancer screening.

"Disappointingly, only 14% of those [identified as potentially eligible] enrolled," he said.

Of the 110 patients ultimately screened, 53% were identified using the tobacco screen, 29% were self-referred, and 18% were physician-referred.

About half of the 418 patients identified as potentially eligible couldn’t be reached by phone, and another third didn’t meet eligibility criteria or didn’t participate for another reason, but only 10 (2%) refused because of cost. The hospital discounted the cost of the CT to $150 for those without insurance coverage.

A comparison of the groups of patients who were self-referred, physician-referred, and identified using the tobacco screen showed that Asian patients, who made up 25% of the total patient population at the hospital, were underrepresented in the tobacco screen group, and those with a history of cancer comprised 82% of the group identified by the tobacco screen, Dr. Raz said. The former finding could be attributed to a language barrier, and the latter finding is not surprising given that the study hospital is a cancer center, Dr. Raz said.

"Lung cancer screening with low-dose radiation CT scans saves lives, it’s safe, and it’s cost effective. The U.S. Preventive Services Task Force recommends lung cancer screening, as do a number of other professional organizations, including the STS [Society of Thoracic Surgeons]," he said.

Still, it is believed that only a minority of those eligible undergo screening, he added, noting that a 2013 survey suggested that the median number of patients screened per year per lung cancer screening program is only 10.

The current findings suggest that augmenting meaningful use tobacco questions as part of a lung cancer screening program is feasible. This approach increased participation in the City of Hope Medical Center screening program.

"We think it’s a method that other centers can use or that primary care physicians can use to identify patients within their programs or within their systems," he said, noting that use of the tobacco screen also provides clinicians with an opportunity for smoking cessation intervention. In addition, the tobacco screen represents a useful research tool in that it systematically collects data on tobacco history.

As the "resource-consuming" nature of the program might be considered a limitation, efforts are underway to implement an automatic alert system based on the EHR to flag patients who meet lung cancer screening criteria and to automatically book a consultation. The program might also be improved by better outreach to non-English-speaking patients, and through systematic referral of high-risk patients, Dr. Raz said.

Dr. Raz reported having no disclosures.

ORLANDO – A novel lung cancer screening program based in part on smoking-related meaningful use criteria proved feasible and was successful for identifying patients at a National Comprehensive Cancer Network cancer center who were eligible for screening.

The program, which was launched in January 2013, led to the screening of 110 patients and the detection and treatment of three stage I lung cancers during the first 7 months, Dr. Dan J. Raz of the City of Hope Medical Center in Duarte, Calif., reported at the annual meeting of the Society of Thoracic Surgeons.

©thinkstockphotos.com

During the first 3 months of the program, before the tobacco screen was developed, only four patients were enrolled – two by physician referral and two by self-referral. At that point, the tobacco screen was implemented, and 418 patients potentially eligible for screening were identified, Dr. Raz said.

The tobacco screen, which contained smoking-related meaningful use criteria established by the Centers for Medicare & Medicaid Services as part of the standards for electronic health records (EHRs), was easily implemented and took an average of less than 2 minutes to complete and enter into the EHR, he noted.

Pack-year calculations and quit dates for former smokers also were included in the tobacco screen.

The lung cancer screening program – known as the tobacco exposure program – was run by a nurse practitioner who also was a licensed tobacco dependency counselor. The tobacco screen was administered to all ambulatory adult patients every 6 months. Weekly electronic reports were generated to identify patients who met criteria for lung cancer screening eligibility.

Those who met the criteria, and who hadn’t undergone a chest or head computed tomography (CT) scan in the prior 12 months and who weren’t undergoing cancer treatment, were contacted to review the information. The primary treating physician also was contacted regarding the plan for lung cancer screening.

"Disappointingly, only 14% of those [identified as potentially eligible] enrolled," he said.

Of the 110 patients ultimately screened, 53% were identified using the tobacco screen, 29% were self-referred, and 18% were physician-referred.

About half of the 418 patients identified as potentially eligible couldn’t be reached by phone, and another third didn’t meet eligibility criteria or didn’t participate for another reason, but only 10 (2%) refused because of cost. The hospital discounted the cost of the CT to $150 for those without insurance coverage.

A comparison of the groups of patients who were self-referred, physician-referred, and identified using the tobacco screen showed that Asian patients, who made up 25% of the total patient population at the hospital, were underrepresented in the tobacco screen group, and those with a history of cancer comprised 82% of the group identified by the tobacco screen, Dr. Raz said. The former finding could be attributed to a language barrier, and the latter finding is not surprising given that the study hospital is a cancer center, Dr. Raz said.

"Lung cancer screening with low-dose radiation CT scans saves lives, it’s safe, and it’s cost effective. The U.S. Preventive Services Task Force recommends lung cancer screening, as do a number of other professional organizations, including the STS [Society of Thoracic Surgeons]," he said.

Still, it is believed that only a minority of those eligible undergo screening, he added, noting that a 2013 survey suggested that the median number of patients screened per year per lung cancer screening program is only 10.

The current findings suggest that augmenting meaningful use tobacco questions as part of a lung cancer screening program is feasible. This approach increased participation in the City of Hope Medical Center screening program.

"We think it’s a method that other centers can use or that primary care physicians can use to identify patients within their programs or within their systems," he said, noting that use of the tobacco screen also provides clinicians with an opportunity for smoking cessation intervention. In addition, the tobacco screen represents a useful research tool in that it systematically collects data on tobacco history.

As the "resource-consuming" nature of the program might be considered a limitation, efforts are underway to implement an automatic alert system based on the EHR to flag patients who meet lung cancer screening criteria and to automatically book a consultation. The program might also be improved by better outreach to non-English-speaking patients, and through systematic referral of high-risk patients, Dr. Raz said.

Dr. Raz reported having no disclosures.

FT. LAUDERDALE, FLA. – Transfusion of packed red blood cells during cardiac surgery is independently associated with increased risk of major infection, researchers reported, and – in a related study – pneumonia was found to be the most common infection associated with cardiac surgery.

Cardiac procedures with transfusions were associated with a significant risk of infection, such that "with every unit of blood, you had a significant increase in the risk of infection for the patient. It appears that there might be some sort of threshold in the 2- to 4-unit range, whereafter the risk really seems to increase. But statistically, even that first drop of blood carried an additional infectious risk," Dr. Keith A. Horvath said at the annual meeting of the Society of Thoracic Surgeons.

In a related study, researchers found pneumonia to be the most common infection associated with cardiac surgery. "Pneumonia, surprisingly, was the most common infection, at 2.4%. This was much more common than other infections that we certainly worry about and get a fair amount of press and literature on, specifically sternal wound infections," said Dr. Gorav Ailawadi of the University of Virginia in Charlottesville.

Data for 5,184 adult cardiac patients were used for both studies. The patients were prospectively enrolled in a 10-center infection registry between February and September, 2010. Captured data included infection occurrence, type, and organism. Adjudication was performed by an independent panel of infectious diseases experts.

Major infections evaluated in the study included deep incisional surgical (chest), deep incisional surgical (second incisions), empyema, endocarditis, mediastinitis, myocarditis, pneumonia, bloodstream infections, Clostridium difficile colitis, and cardiac device infections. Infections were defined by a combination of clinical, laboratory, and/or radiologic evidence (according to Centers for Disease Control and Prevention surveillance definitions) for a follow-up of 65 days.

The researchers included several types of surgical interventions: isolated coronary artery bypass graft (CABG), isolated valve surgery, CABG with valve surgery, surgery for heart failure, thoracic aortic surgery, and other procedures.

The mean patient age was 64 years, mean bypass time was 115 minutes, two-thirds (67%) were men, 71% had heart failure, a quarter (27%) had diabetes, 14% had chronic obstructive pulmonary disease (COPD), and 19% had prior cardiac surgery. Mean hemoglobin was 13.2 mg/dL.

There was a significant dose-dependent association between quantity of packed red blood cells (PRBCs) and risk of infection, with the crude risk increasing by an average of 29% with each PRBC unit.

Several factors increased the risk of infection, including severe COPD (relative risk, 1.85), preoperative creatinine levels greater than 1.5 mg/dL (RR, 1.72), heart failure (RR, 1.49), mild to moderate COPD (RR, 1.36), PRBCs per unit (RR, 1.24), and surgery time per 60 minutes (RR, 1.19).

Platelet transfusion occurred in 31% of patients. However, the use of platelets was associated with a decreased risk of infection (RR, 0.71). Cell Saver use was not related to infection.

Creatinine levels greater than 1.5 mg/dL (RR, 2.40) and PRBCs per unit (RR, 1.23) significantly increased the risk of death. Many factors significantly increased the length of stay, including creatinine levels greater than 1.5 mg/dL (RR, 1.26), severe COPD (RR, 1.41), mild to moderate COPD (RR, 1.14), heart failure (RR, 1.36), PRBCs (RR, 1.12), surgery time per 60 minutes (RR, 1.11), age of 65-79 years (RR, 1.21), and age older than 80 years (RR, 1.44). The use of platelets was associated with a decreased length of stay (RR, 0.71).

All risks of transfusion must be weighed against toleration anemia, which is also associated with adverse outcomes, according to Dr. Horvath, who is the director of the Cardiothoracic Surgery Research Program for the National Heart, Lung, and Blood Institute and a member of the Cardiothoracic Surgery Trials Network.

Efforts to reduce PRBC transfusions may significantly reduce major postoperative infections. Cell salvage and ultrafiltration could be viable alternatives, he noted.

In the second study, the researchers used the same dataset. Captured data included infection occurrence, type, timing, and organisms. Infections were adjudicated by an independent panel of infectious disease experts. The risk of pneumonia, mortality, and length of stay (time to discharge) were analyzed.

Major infections included bloodstream, pneumonia, C. difficile, deep sternal incisional, mediastinitis, deep groin/leg incisional, endocarditis, and empyema.

Pneumonia was diagnosed using the 2010 surveillance criteria from the CDC/National Healthcare Safety Network, including chest x-ray with new or progressive and persistent infiltrate; fever greater than 38° C; leukopenia (defined as fewer than 4,000 leukocytes per cc); leukocytosis (at least 12,000 leukocytes per cc); or altered mental status. At least two of the following must have been present as well: purulent sputum or change; cough, dyspnea, or tachypnea; rales or bronchial breath sounds; or worsening gas exchange. Duration of follow-up was 65 days.

In all, 31% had isolated CABG, 30% had isolated valve surgery, 11% had CABG and valve surgery, 6% had thoracic aortic surgery, 2% had left ventricular assist device (LVAD) implantation/heart transplant, and 20% were categorized as other.

Overall, 2.4% of patients in the registry had pneumonia, 1.1% had blood stream infection, 1% had C. difficile colitis, and 0.5% had deep sternal infections.

The overall mean time to infection was 19 days and the median was 14 days. The mean time to infection for pneumonia was 15 days. Overall, more than 40% of infections occurred after the index hospitalization. However, 68% and 66% of pneumonias and blood stream infections, respectively, occurred during hospitalization. The three most common organisms were Pseudomonas aeruginosa (12%), Enterobacter cloacae (8%), and Klebsiella pneumoniae (7%).

Increased risk of pneumonia was associated with surgery time (RR, 1.42), a creatinine level of at least 1.5 mg/dL (RR, 1.94), mild to moderate COPD (RR, 1.78), severe COPD (RR, 4.12), and heart failure (RR, 1.76). The reference category was those without COPD.

In terms of process-of-care factors, only nasal decontamination with mupirocin was associated with reduced risk of pneumonia (RR, 0.77). Nasal decontamination with other agents (RR, 1.44); antibiotics given within 24 hours after surgery (RR, 1.26) and within 48 hours postop (RR, 2.70); ventilator use of 24-48 hours (RR, 2.31) and more than 48 hours (RR, 4.58); nasogastric tube (RR, 2.07); and use of PRBCs (RR, 1.10) were all associated with increased risk of pneumonia.

In terms of mortality, "pneumonia, among all the factors analyzed, had the greatest association with mortality, with an odds ratio greater than seven ... which was far and away greater than anything else that was examined," said Dr. Ailawadi.

Pneumonia was significantly associated with an increased risk of mortality (RR, 7.07), as were heart failure (RR, 1.87), creatinine levels of at least 1.5 mg/dL (RR, 2.97), and surgery duration (1.27). However, black race appeared to be protective, with a significantly decreased risk of pneumonia (RR, 0.43).

Pneumonia significantly increased the length of stay by a median of 13 days (19 days with pneumonia and 6 days without). A number of factors – mild to moderate COPD, severe COPD, heart failure, creatinine levels of at least 1.5 mg/dL, surgery time, age of 65-79 years, age 80 years and older, and black or Hispanic race – were significantly associated with increased risk of longer length of stay. Male sex was significantly associated with decreased length of stay (RR, 0.79).

Both Dr. Horvath and Dr. Ailawadi reported that they have no relevant financial disclosures.

FT. LAUDERDALE, FLA. – Transfusion of packed red blood cells during cardiac surgery is independently associated with increased risk of major infection, researchers reported, and – in a related study – pneumonia was found to be the most common infection associated with cardiac surgery.

Cardiac procedures with transfusions were associated with a significant risk of infection, such that "with every unit of blood, you had a significant increase in the risk of infection for the patient. It appears that there might be some sort of threshold in the 2- to 4-unit range, whereafter the risk really seems to increase. But statistically, even that first drop of blood carried an additional infectious risk," Dr. Keith A. Horvath said at the annual meeting of the Society of Thoracic Surgeons.

In a related study, researchers found pneumonia to be the most common infection associated with cardiac surgery. "Pneumonia, surprisingly, was the most common infection, at 2.4%. This was much more common than other infections that we certainly worry about and get a fair amount of press and literature on, specifically sternal wound infections," said Dr. Gorav Ailawadi of the University of Virginia in Charlottesville.

Data for 5,184 adult cardiac patients were used for both studies. The patients were prospectively enrolled in a 10-center infection registry between February and September, 2010. Captured data included infection occurrence, type, and organism. Adjudication was performed by an independent panel of infectious diseases experts.

Major infections evaluated in the study included deep incisional surgical (chest), deep incisional surgical (second incisions), empyema, endocarditis, mediastinitis, myocarditis, pneumonia, bloodstream infections, Clostridium difficile colitis, and cardiac device infections. Infections were defined by a combination of clinical, laboratory, and/or radiologic evidence (according to Centers for Disease Control and Prevention surveillance definitions) for a follow-up of 65 days.

The researchers included several types of surgical interventions: isolated coronary artery bypass graft (CABG), isolated valve surgery, CABG with valve surgery, surgery for heart failure, thoracic aortic surgery, and other procedures.

The mean patient age was 64 years, mean bypass time was 115 minutes, two-thirds (67%) were men, 71% had heart failure, a quarter (27%) had diabetes, 14% had chronic obstructive pulmonary disease (COPD), and 19% had prior cardiac surgery. Mean hemoglobin was 13.2 mg/dL.

There was a significant dose-dependent association between quantity of packed red blood cells (PRBCs) and risk of infection, with the crude risk increasing by an average of 29% with each PRBC unit.

Several factors increased the risk of infection, including severe COPD (relative risk, 1.85), preoperative creatinine levels greater than 1.5 mg/dL (RR, 1.72), heart failure (RR, 1.49), mild to moderate COPD (RR, 1.36), PRBCs per unit (RR, 1.24), and surgery time per 60 minutes (RR, 1.19).

Platelet transfusion occurred in 31% of patients. However, the use of platelets was associated with a decreased risk of infection (RR, 0.71). Cell Saver use was not related to infection.

Creatinine levels greater than 1.5 mg/dL (RR, 2.40) and PRBCs per unit (RR, 1.23) significantly increased the risk of death. Many factors significantly increased the length of stay, including creatinine levels greater than 1.5 mg/dL (RR, 1.26), severe COPD (RR, 1.41), mild to moderate COPD (RR, 1.14), heart failure (RR, 1.36), PRBCs (RR, 1.12), surgery time per 60 minutes (RR, 1.11), age of 65-79 years (RR, 1.21), and age older than 80 years (RR, 1.44). The use of platelets was associated with a decreased length of stay (RR, 0.71).

All risks of transfusion must be weighed against toleration anemia, which is also associated with adverse outcomes, according to Dr. Horvath, who is the director of the Cardiothoracic Surgery Research Program for the National Heart, Lung, and Blood Institute and a member of the Cardiothoracic Surgery Trials Network.

Efforts to reduce PRBC transfusions may significantly reduce major postoperative infections. Cell salvage and ultrafiltration could be viable alternatives, he noted.

In the second study, the researchers used the same dataset. Captured data included infection occurrence, type, timing, and organisms. Infections were adjudicated by an independent panel of infectious disease experts. The risk of pneumonia, mortality, and length of stay (time to discharge) were analyzed.

Major infections included bloodstream, pneumonia, C. difficile, deep sternal incisional, mediastinitis, deep groin/leg incisional, endocarditis, and empyema.

Pneumonia was diagnosed using the 2010 surveillance criteria from the CDC/National Healthcare Safety Network, including chest x-ray with new or progressive and persistent infiltrate; fever greater than 38° C; leukopenia (defined as fewer than 4,000 leukocytes per cc); leukocytosis (at least 12,000 leukocytes per cc); or altered mental status. At least two of the following must have been present as well: purulent sputum or change; cough, dyspnea, or tachypnea; rales or bronchial breath sounds; or worsening gas exchange. Duration of follow-up was 65 days.

In all, 31% had isolated CABG, 30% had isolated valve surgery, 11% had CABG and valve surgery, 6% had thoracic aortic surgery, 2% had left ventricular assist device (LVAD) implantation/heart transplant, and 20% were categorized as other.

Overall, 2.4% of patients in the registry had pneumonia, 1.1% had blood stream infection, 1% had C. difficile colitis, and 0.5% had deep sternal infections.

The overall mean time to infection was 19 days and the median was 14 days. The mean time to infection for pneumonia was 15 days. Overall, more than 40% of infections occurred after the index hospitalization. However, 68% and 66% of pneumonias and blood stream infections, respectively, occurred during hospitalization. The three most common organisms were Pseudomonas aeruginosa (12%), Enterobacter cloacae (8%), and Klebsiella pneumoniae (7%).

Increased risk of pneumonia was associated with surgery time (RR, 1.42), a creatinine level of at least 1.5 mg/dL (RR, 1.94), mild to moderate COPD (RR, 1.78), severe COPD (RR, 4.12), and heart failure (RR, 1.76). The reference category was those without COPD.

In terms of process-of-care factors, only nasal decontamination with mupirocin was associated with reduced risk of pneumonia (RR, 0.77). Nasal decontamination with other agents (RR, 1.44); antibiotics given within 24 hours after surgery (RR, 1.26) and within 48 hours postop (RR, 2.70); ventilator use of 24-48 hours (RR, 2.31) and more than 48 hours (RR, 4.58); nasogastric tube (RR, 2.07); and use of PRBCs (RR, 1.10) were all associated with increased risk of pneumonia.

In terms of mortality, "pneumonia, among all the factors analyzed, had the greatest association with mortality, with an odds ratio greater than seven ... which was far and away greater than anything else that was examined," said Dr. Ailawadi.

Pneumonia was significantly associated with an increased risk of mortality (RR, 7.07), as were heart failure (RR, 1.87), creatinine levels of at least 1.5 mg/dL (RR, 2.97), and surgery duration (1.27). However, black race appeared to be protective, with a significantly decreased risk of pneumonia (RR, 0.43).

Pneumonia significantly increased the length of stay by a median of 13 days (19 days with pneumonia and 6 days without). A number of factors – mild to moderate COPD, severe COPD, heart failure, creatinine levels of at least 1.5 mg/dL, surgery time, age of 65-79 years, age 80 years and older, and black or Hispanic race – were significantly associated with increased risk of longer length of stay. Male sex was significantly associated with decreased length of stay (RR, 0.79).

Both Dr. Horvath and Dr. Ailawadi reported that they have no relevant financial disclosures.

FT. LAUDERDALE, FLA. – Transfusion of packed red blood cells during cardiac surgery is independently associated with increased risk of major infection, researchers reported, and – in a related study – pneumonia was found to be the most common infection associated with cardiac surgery.

Cardiac procedures with transfusions were associated with a significant risk of infection, such that "with every unit of blood, you had a significant increase in the risk of infection for the patient. It appears that there might be some sort of threshold in the 2- to 4-unit range, whereafter the risk really seems to increase. But statistically, even that first drop of blood carried an additional infectious risk," Dr. Keith A. Horvath said at the annual meeting of the Society of Thoracic Surgeons.

In a related study, researchers found pneumonia to be the most common infection associated with cardiac surgery. "Pneumonia, surprisingly, was the most common infection, at 2.4%. This was much more common than other infections that we certainly worry about and get a fair amount of press and literature on, specifically sternal wound infections," said Dr. Gorav Ailawadi of the University of Virginia in Charlottesville.

Data for 5,184 adult cardiac patients were used for both studies. The patients were prospectively enrolled in a 10-center infection registry between February and September, 2010. Captured data included infection occurrence, type, and organism. Adjudication was performed by an independent panel of infectious diseases experts.

Major infections evaluated in the study included deep incisional surgical (chest), deep incisional surgical (second incisions), empyema, endocarditis, mediastinitis, myocarditis, pneumonia, bloodstream infections, Clostridium difficile colitis, and cardiac device infections. Infections were defined by a combination of clinical, laboratory, and/or radiologic evidence (according to Centers for Disease Control and Prevention surveillance definitions) for a follow-up of 65 days.

The researchers included several types of surgical interventions: isolated coronary artery bypass graft (CABG), isolated valve surgery, CABG with valve surgery, surgery for heart failure, thoracic aortic surgery, and other procedures.

The mean patient age was 64 years, mean bypass time was 115 minutes, two-thirds (67%) were men, 71% had heart failure, a quarter (27%) had diabetes, 14% had chronic obstructive pulmonary disease (COPD), and 19% had prior cardiac surgery. Mean hemoglobin was 13.2 mg/dL.

There was a significant dose-dependent association between quantity of packed red blood cells (PRBCs) and risk of infection, with the crude risk increasing by an average of 29% with each PRBC unit.

Several factors increased the risk of infection, including severe COPD (relative risk, 1.85), preoperative creatinine levels greater than 1.5 mg/dL (RR, 1.72), heart failure (RR, 1.49), mild to moderate COPD (RR, 1.36), PRBCs per unit (RR, 1.24), and surgery time per 60 minutes (RR, 1.19).

Platelet transfusion occurred in 31% of patients. However, the use of platelets was associated with a decreased risk of infection (RR, 0.71). Cell Saver use was not related to infection.

Creatinine levels greater than 1.5 mg/dL (RR, 2.40) and PRBCs per unit (RR, 1.23) significantly increased the risk of death. Many factors significantly increased the length of stay, including creatinine levels greater than 1.5 mg/dL (RR, 1.26), severe COPD (RR, 1.41), mild to moderate COPD (RR, 1.14), heart failure (RR, 1.36), PRBCs (RR, 1.12), surgery time per 60 minutes (RR, 1.11), age of 65-79 years (RR, 1.21), and age older than 80 years (RR, 1.44). The use of platelets was associated with a decreased length of stay (RR, 0.71).

All risks of transfusion must be weighed against toleration anemia, which is also associated with adverse outcomes, according to Dr. Horvath, who is the director of the Cardiothoracic Surgery Research Program for the National Heart, Lung, and Blood Institute and a member of the Cardiothoracic Surgery Trials Network.

Efforts to reduce PRBC transfusions may significantly reduce major postoperative infections. Cell salvage and ultrafiltration could be viable alternatives, he noted.

In the second study, the researchers used the same dataset. Captured data included infection occurrence, type, timing, and organisms. Infections were adjudicated by an independent panel of infectious disease experts. The risk of pneumonia, mortality, and length of stay (time to discharge) were analyzed.

Major infections included bloodstream, pneumonia, C. difficile, deep sternal incisional, mediastinitis, deep groin/leg incisional, endocarditis, and empyema.

Pneumonia was diagnosed using the 2010 surveillance criteria from the CDC/National Healthcare Safety Network, including chest x-ray with new or progressive and persistent infiltrate; fever greater than 38° C; leukopenia (defined as fewer than 4,000 leukocytes per cc); leukocytosis (at least 12,000 leukocytes per cc); or altered mental status. At least two of the following must have been present as well: purulent sputum or change; cough, dyspnea, or tachypnea; rales or bronchial breath sounds; or worsening gas exchange. Duration of follow-up was 65 days.

In all, 31% had isolated CABG, 30% had isolated valve surgery, 11% had CABG and valve surgery, 6% had thoracic aortic surgery, 2% had left ventricular assist device (LVAD) implantation/heart transplant, and 20% were categorized as other.

Overall, 2.4% of patients in the registry had pneumonia, 1.1% had blood stream infection, 1% had C. difficile colitis, and 0.5% had deep sternal infections.

The overall mean time to infection was 19 days and the median was 14 days. The mean time to infection for pneumonia was 15 days. Overall, more than 40% of infections occurred after the index hospitalization. However, 68% and 66% of pneumonias and blood stream infections, respectively, occurred during hospitalization. The three most common organisms were Pseudomonas aeruginosa (12%), Enterobacter cloacae (8%), and Klebsiella pneumoniae (7%).

Increased risk of pneumonia was associated with surgery time (RR, 1.42), a creatinine level of at least 1.5 mg/dL (RR, 1.94), mild to moderate COPD (RR, 1.78), severe COPD (RR, 4.12), and heart failure (RR, 1.76). The reference category was those without COPD.

In terms of process-of-care factors, only nasal decontamination with mupirocin was associated with reduced risk of pneumonia (RR, 0.77). Nasal decontamination with other agents (RR, 1.44); antibiotics given within 24 hours after surgery (RR, 1.26) and within 48 hours postop (RR, 2.70); ventilator use of 24-48 hours (RR, 2.31) and more than 48 hours (RR, 4.58); nasogastric tube (RR, 2.07); and use of PRBCs (RR, 1.10) were all associated with increased risk of pneumonia.

In terms of mortality, "pneumonia, among all the factors analyzed, had the greatest association with mortality, with an odds ratio greater than seven ... which was far and away greater than anything else that was examined," said Dr. Ailawadi.

Pneumonia was significantly associated with an increased risk of mortality (RR, 7.07), as were heart failure (RR, 1.87), creatinine levels of at least 1.5 mg/dL (RR, 2.97), and surgery duration (1.27). However, black race appeared to be protective, with a significantly decreased risk of pneumonia (RR, 0.43).

Pneumonia significantly increased the length of stay by a median of 13 days (19 days with pneumonia and 6 days without). A number of factors – mild to moderate COPD, severe COPD, heart failure, creatinine levels of at least 1.5 mg/dL, surgery time, age of 65-79 years, age 80 years and older, and black or Hispanic race – were significantly associated with increased risk of longer length of stay. Male sex was significantly associated with decreased length of stay (RR, 0.79).

Both Dr. Horvath and Dr. Ailawadi reported that they have no relevant financial disclosures.