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Eur J Cardiothorac Surg 2001;20:930-936
© 2001 Elsevier Science NL

Preoperative prediction of prolonged mechanical ventilation following coronary artery bypass grafting

J.F. Légaré, G.M. Hirsch, K.J. Buth, C. MacDougall, J.A. Sullivan

Dalhousie University, Halifax, Nova Scotia, Canada

Received 27 December 2000; received in revised form 18 July 2001; accepted 20 July 2001.

Corresponding author. New Halifax Infirmary QEII HSC, 1796 Summer St Rm 2269, Division of Cardiac Surgery, Halifax, Nova-Scotia, Canada B3H 3A7. Tel.: +1-902-473-7597; fax: +1-902-473-4448
e-mail: ghirsch{at}is.dal.ca


   Abstract
Top
 Abstract
1. Introduction
 2. Materials and methods
 3. Results
 4. Discussion
 References
 
Objective: Few studies have attempted to evaluate who would require prolonged mechanical ventilation following heart surgery. The objectives of this study were to identify predictors of prolonged ventilation in a large group of coronary artery bypass grafting (CABG) patients from a single institution. Methods: One thousand, eight hundred and twenty-nine consecutive patients undergoing CABG were reviewed retrospectively and evaluated for preoperative predictors of prolonged ventilation which included: age, gender, ejection fraction (EF), renal function, diabetes, angina status, New York Heart Association Class, number of diseased vessels, urgency of the procedure, re-operation, chronic lung disease (COPD) and intraoperative variables such as IABP, inotropes, stroke and myocardial infarction. Prolonged ventilation was defined as >=24 h. Stepwise logistic regression analysis was performed. Results: Patients were on average 65.4±10.6 years of age, 30% were diabetic, 80% had triple vessel disease and 93% were of functional class III/IV. The mean ejection fraction was 60±16 percent. Overall peri-operative mortality was 2.7%. There were 157 patients that required prolonged ventilation with a peri-operative mortality of 18.5% (P<0.001). Preoperative independent predictors of prolonged ventilation were found to be: unstable angina (OR 5.6), EF<50 (OR 2.3), COPD (OR 2.0), preop. renal failure (OR 1.9), female gender (OR 1.8) and age>70 (OR 1.7). Based on these predictors, a model was created to estimate of the risk of prolonged ventilation in individual patients following CABG with results ranging from <=3% in patients without any risk factors to >=32% in patients with five or more independent risk factors.Certain intraoperative variables were strong predictors of prolonged ventilation and included: stroke (OR 12.3), re-operation for bleeding (OR 6.9) and perioperative MI (OR 5.8). Conclusion: We were able to create a stable model where several preoperative and intra-operative variables were shown to be predictive of prolonged ventilation after CABG surgery. The ability to identify patients at increased risk for prolonged ventilation may allow the development of pre-emptive strategies and more effective resource allocation.

Key Words: Coronary artery bypass grafting • Ventilation


   1. Introduction
Top
 Abstract
 1. Introduction
2. Materials and methods
 3. Results
 4. Discussion
 References
 
Coronary artery bypass grafting (CABG) surgery is an established treatment for patients with ischemic heart disease. It is one of the most commonly performed surgical interventions with over 16 500 cases performed in Canada and 650 000 in the United States annually [1]. Pre-operative, operative and post-operative care of CABG patients is associated with substantial utilization of health care resources. Current economic constraints in the health care system has lead to significant efforts to shorten length of hospitalization and reduce health care cost [2,3]. To achieve this, many programs have adopted policies to foster shorter intensive care unit stay in an effort to shorten hospitalization and reduce overall costs since these have been shown to be safe in patients following CABG [4].

Survival has improved steadily over the past decade despite increasing application of CABG procedures to an older patient population with more co-morbidities and a higher risk profile [5]. Adverse respiratory system events such as respiratory failure and pneumonia have been traditionally the leading cause of post-operative complications [6]. Prolonged mechanical ventilation is known to result in increased intensive care unit length of stay (ICU), decreased hospital bed availability, increased resource utilization and health care cost. Prolonged mechanical ventilation has also been suggested to result in worse physiological outcomes for patients post-extubation as a result of atelectasis and intra-pulmonary shunting [4]. In fact there are many well-documented benefits to early extubation especially respiratory and cardiovascular [7,8]. However, few studies have attempted to evaluate preoperative predictors of prolonged ventilation in a population of patients undergoing CABG surgery [2,9]. Preoperative patient demographics, lung function tests and blood gas parameters have not always allowed reliable predictions of who would require prolonged ventilation [6,10].

The objectives of this study were to identify predictors of prolonged ventilation in a large group of CABG patients from a single institution. Such knowledge could allow better planning of resource allocation and guide some preventive strategies.


   2. Materials and methods
Top
 Abstract
 1. Introduction
 2. Materials and methods
3. Results
 4. Discussion
 References
 
2.1. Patients
One thousand, eight hundred and twenty-nine consecutive patients undergoing CABG surgery at a single university affiliated institution between January 1997 and March 1999 were reviewed retrospectively. Inclusion into the study was based on the availability of all the following preoperative variables: age, gender, ejection fraction (EF), renal function, diabetes, angina status, New York Heart Association Class (NYHA), number of diseased vessels, urgency of the procedure, re-operation, and history of chronic lung disease (COPD). A total of 1805 patients were included in the multivariate analysis with 24 patients excluded because of missing preoperative data, which mostly consisted of EF (98.7% inclusion). Indications for CABG surgery was based on a weekly peer review process involving cardiologist, cardiac surgeons and cardiac radiologists such that individual patients were wait listed according to urgency of procedure. Cardiopulmonary bypass (CPB) for coronary bypass surgery at our institution was performed in a standardized fashion. Body temperature during the procedure was allowed to drift to approximately 32°C. Standard cardioplegia used was intermittent cold blood delivered antegrade unless otherwise indicated. Patients who had beating heart surgery (OPCAB) were not included in this analysis in an attempt to standardize our model (n=114).

2.2. Data collection
Perioperative patient variables were collected on Society of Thoracic Surgeons (STS) forms, by three full time research assistants, and maintained in a computer data base format (Summit Medical Systems, Inc. MN, USA, 1997). This has been a standard practice at this institution for all cardiac surgical cases since 1995 with data element validation. EF were assessed by left heart catheterization preoperatively. Duration of mechanical ventilation was from the time of arrival to ICU to the time of extubation. Prolonged ventilation was defined as any mechanical ventilation of more than 24 h as defined by the STS guidelines. Urgency status was also determined using the standard STS Cardiac Surgery Database definitions. An elective case was defined as a patient being stable for more than 24 h prior to the procedure, urgent operation required a procedure to be performed within 24 h to prevent further clinical deterioration, and emergent/emergent salvage in patients who required an immediate operation.

2.3. Clinical decision making
The decision to extubate was made on an individual, patient-by-patient basis by one of the seven attending cardiovascular surgeons, two cardiac anesthetists, supporting resident housestaff and/or nurse taking care of the patient. To be considered for extubation patients had to be warm (>35°C), awake, hemodynamically stable, and have the following gas exchange findings on arterial blood gas: PO2 >60, PCO2 <55 and pH of more than 7.30. Patients were generally not extubated early after surgery if they were considered at risk clinically for decreased oxygen delivery. This included patients with signs of inadequate tissue perfusion (lactate levels >2, mixed venous oxygen saturation <60%, urine output <0.5 ml/kg/h, cardiac index <2 l/m2 min), significant hemodynamic instability, patients requiring two or more inotropes, utilization of a intra-aortic balloon pump (IABP) or a ventricular assist device (VAD), and patients with multi-organ dysfunction.

2.4. Data analysis
Descriptive statistics were obtained for all variables using the SAS software package (SAS, Cary, North Carolina). These included continuous and discrete variables which were analyzed accordingly with an unpaired t-test, chi-square test, and Fisher exact test. Logistic regression model was developed to predict the occurrence of prolonged ventilation based on pre-operative variables in patients undergoing CABG. Pre-operative variables were chosen from previous studies predicting outcomes following CABG surgery [5,11,12]. Forward selection within the regression model was stepwise where variables were retained if their associated P value were <=0.05. A c statistic was calculated as a measure of the explanatory power of the logistic regression model. The c statistic is equivalent to the area under the receiver-operating-characteristic (ROC) curve where a c value of 0.5 indicates no discriminatory power, whereas a c value of 1.0 indicates a perfect discrimination between patients requiring prolonged mechanical ventilation. The model c-statistic was 0.81 and the goodness of fit statistic for the model was P=0.92 indicating a good, stable fit of the model.


   3. Results
Top
 Abstract
 1. Introduction
 2. Materials and methods
 3. Results
4. Discussion
 References
 
3.1. Patient characteristics
The patients enrolled in this study represent a typical referral practice for most Canadian centers [13]. Patients were predominantly male with an average age of 65.4±10.6 years with 38% being over 70 years of age. More than 30% were diabetic with a mean EF of 60±16 percent. Twenty-four percent of patients had an EF of less than 50 and ranged from 9 to 92%. Patients mostly had triple vessel disease (80%) and were of functional class III or IV (93%). Complete pre-operative patient demographics are illustrated in Table 1. Both urgency status and angina class definitions were based on STS guidelines outlined in the methods section of this manuscript.


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  		Table 1. Pre-operative characteristics 1829 patients undergoing CABG surgery at a single institution between 1997 and 1999a

 
3.2. Patient outcomes
Out of 1829 CABG procedures performed there were 49 perioperative deaths (2.7% mortality rate). One hundred and fifty seven patients required ventilation for more than 24 h (8.6%) after surgery with a mortality rate of 18.5% (P<0.001). Patients ventilated for more than 24 h were ventilated for an average of 7.9±8.5 days (range 2–255 days) (Fig. 1). The overall median length of hospitalization was 7 days with a range of 3–177 days.



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  		Fig. 1. Graph illustrating the distribution over time of patients ventilated for greater than 24 h (n=157).

 
The use of intra-aortic balloon pump (IABP) was defined as any IABP use peri-operatively and was required in 8.4% of patients. Inotropes were utilized in 14.7% of patients and were defined as any inotrope used post-operatively, the most common of which was dopamine (Abbot Laboratories, PQ, Canada). Blood product use included: fresh frozen plasma, cryoprecipitate, platelets or packed red blood cells, and was limited to 22.1% of patients with 15 (0.8%) patients re-operated for bleeding. The incidence of peri-operative MI was 0.9% and permanent stroke 1.7%. Details of surgical outcomes are illustrated in Table 2.


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  		Table 2. Operative results following CABG (n=1829)a

 
3.3. Univariate predictors
Pre-operative patient characteristics and intra-operative variables were then evaluated univariately as predictors of prolonged ventilation defined as greater or equal to 24 h. These are listed in order of decreasing odds ratio in Table 3. The strongest univariate predictor for prolonged mechanical ventilation was the presence of an IABP with an odds ratio of 22.8, and the lower significant predictor was re-operation with an odds ratio of 1.7. The number of diseased vessels, diabetes and NYHA were not significantly associated with prolonged ventilation.


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  		Table 3. Univariate predictors of prolonged mechanical ventilation following CABG surgerya

 
3.4. Multivariate predictors
Table 4 shows the logistic regression model for predicting the occurrence of prolonged ventilation; this model was developed as described in the materials and methods. The predictors are listed in descending order of the odds ratio magnitude. The three most powerful predictors of prolonged mechanical ventilation were found to correspond to intraoperative variables or complications: permanent stroke, re-operation for bleeding and perioperative myocardial infarction. On the other hand independent pre-operative predictors of prolonged mechanical ventilation were found to be: unstable angina, ejection fraction of less than 50, history of chronic obstructive lung disease, preoperative renal failure (creatinine >177), female gender and age greater than 70. Coefficients obtained from the logistic regression were then utilized to create a clinically meaningful predictive model using preoperative predictors only, not intraoperative variables. This predictive model allows one to estimate the preoperative risk of prolonged mechanical ventilation in individual patients expressed as a percent risk with 95% confidence interval (Figs. 2 and 3). In summary, patients with no risk factors have a less than a 3% risk of requiring prolonged mechanical ventilation after CABG as compared to a greater than 32% risk in patients with five or more risk factors (Fig. 3).


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  		Table 4. Multivariate predictors of prolonged mechanical ventilation obtained by logistic regression analysisa

 


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  		Fig. 2. Model predicting pre-operatively prolonged mechanical ventilation based on coefficients from the logistic regression model and illustrated as a percent risk of requiring prolonged mechanical ventilation. Risk factors were evaluated in isolation. EF, ejection fraction.

 


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  		Fig. 3. Model predicting pre-operatively prolonged mechanical ventilation based on coefficients from the logistic regression model and illustrated as a percent risk of requiring prolonged mechanical ventilation. Risk of prolonged ventilation was evaluated as a combination of one to five risk factors. Patients with six risk factors resulted in a 73% (range 4–100%) risk of prolonged ventilation with wide confidence intervals presumably because no patients in this study were found to have all six pre-operative risk factors.

 

   4. Discussion
Top
 Abstract
 1. Introduction
 2. Materials and methods
 3. Results
 4. Discussion
References
 
Patients undergoing isolated CABG surgery at our institution are usually mechanically ventilated for less than 24 h, are discharged from ICU within 24 h and often discharged home within 1 week after surgery [11]. Efforts to extubate patients early after heart surgery have been based on studies that demonstrate the safety and potential to reduce length of hospitalization of such approaches [2,4,14]. However, because CABG operations continue to be commonly performed, and represent a significant usage of health care resources, an ability to predict which patients would require prolonged mechanical ventilation with associated prolonged ICU stay and length of hospitalization, could help allocate adequate resources and may lead to the developments of preventive strategies [9]. Contrary to many studies we have defined prolonged ventilation as greater than 24 h because it approximates most closely current clinical practice [11,15]. Others have utilized a cutoff from 36 h to 6 days for the definition of prolonged ventilation but these cutoffs would have resulted in lower event rates we feel are less clinically relevant [9,10,16–18].

The patient population evaluated in this study was representative of most large cardiac surgical centers in Canada [13]. A significant proportion of patients were older than 70 years of age (38%), 7.8% were re-operations and 92.8% were of functional class III or IV (NYHA). While the percentage of patients undergoing elective procedures reached 83%, it should be noted that this figure includes patients awaiting surgery in an in-hospital setting in accordance with the Society for Thoracic Surgeons database definitions. Many ‘elective’ patients require systemic heparin and/or i.v. nitrates and were not considered unstable enough to require an operation within 24 h. This indirectly reflects the status of waiting lists in Canada where hospitalized patients may wait days prior to their operative procedure with unstable anginal syndromes.

In this series of 1829 patients undergoing CABG surgery there was an 8.6% incidence of prolonged mechanical ventilation, which was associated with significant mortality (18.5%) as compared to CABG patients who did not require ventilation for more than 24 h (1.2%). This finding does not suggest that prolonged ventilation necessarily results in increased mortality but identifies a group of patient at increased risk of morbidity and mortality following coronary bypass surgery. In an attempt to predict pre-operatively who these patients are, a multiple logistic regression analysis was used to identify independent predictors of prolonged mechanical ventilation. Six independent predictors were identified and include: unstable angina, low ejection fraction, COPD, pre-op renal failure, female gender and advanced age. Interestingly, several variables were not found to be independent risk factors for prolonged ventilation despite many of them being often considered markers of disease severity. Non-predictive variables included: reoperation, number of diseased vessels, diabetes, emergent surgery, NYHA III or IV, and a left ventricular end diastolic pressure of greater than 20.

The strongest predictor was unstable angina with a 5.2-fold higher (9.3% risk) incidence of prolonged ventilation compared with stable angina. However, it is important to note that unstable angina was defined as patients with refractory angina that required hospitalization, ICU admission and parenteral nitrates to control symptoms. This definition is very stringent and differs from common practice where any change from a previous angina state or new diagnosis defines unstable angina. In our study, unstable angina was an important marker of disease severity, and acuteness of disease. Preoperative unstable angina has also been reported by others to predict prolonged intubation following CABG surgery [2].

Ventricular dysfunction was also found to be an independent predictor of prolonged ventilation. Patients with an EF of less than 50% had a 2.3-fold increased incidence (4.1% risk) of prolonged ventilation. An EF of less than 50% was chosen arbitrarily because clinically it includes most patients with left ventricular dysfunction ranging from mild, moderate to severe. We demonstrate that EF continues to be a very strong predictor of mortality and morbidity in CABG patients [10,19,20].

COPD represents a broad spectrum of lung diseases often difficult to define. Patients with COPD undergoing cardiac operations are influenced negatively by both sternotomy and CPB with respect to post-operative pulmonary complications [21]. We Have shown that patients with a history of COPD have a 2-fold increased incidence of prolonged ventilation (3.5% risk). This is in keeping with other studies suggesting that prolonged ventilation (>48 h) is seen in 5.2% of patients with COPD as compared to 2.8% of patients without when undergoing CABG surgery [22]. These studies have also suggested that patients with COPD have a proportionally higher mortality rate [22].

Patients with pre-operative renal failure defined as a creatinine of greater or equal to 177 were found to have a 1.9-fold increased incidence of prolonged ventilation (3.3% risk). This group includes patients which were both dialysis and non-dialysis dependent. Renal failure defined as such has been previously shown to be associated with worse outcome following cardiac surgery with resulting prolonged length of hospitalization often associated with prolonged mechanical ventilation and ICU stay [11].

Female gender is believed by many to be a predictor of increased mortality and morbidity following CABG surgery for reasons that are not entirely clear and that are not simply related to a small body surface area [21]. In the current study female patients had a 1.8-fold increased incidence of prolonged ventilation (3.2% risk). Our findings are also supported by a recent evidence suggesting that female patients have longer intubation times, intensive care unit stays and length of hospitalization [23].

Seventy years of age was chosen in this study as a cutoff for advanced age since the mean age of CABG patients was 65 years with 38% of patients older than 70 years of age. Patients older than 70 were shown to be 1.7-fold more likely (3% risk) to be ventilated for longer than 24 h after CABG just on the basis of their age. Age has been suggested by others to be a predictor for prolonged intubation [2], result in prolong ventilation [24] and independently be associated with increased long-term mortality [24,25]. Taken together with a steady increase in the age of CABG patients over time [5], this finding will have important implications for future health care resource utilization [9]. If current trends in patient demographics continue one could project in the near future significant increases in ICU bed utilization by an increasing proportion of elderly patients resulting in further pressures on the current health care systems.

Most outcome studies have focused on mortality or adverse outcomes in the broader sense following CABG [12,17]. Few have attempted to evaluate pre-operative parameters to predict post-operative respiratory outcome but have identified in common age as a predictor of prolonged mechanical ventilation following CABG [2,10,15]. However, one must take into consideration that definitions for prolonged ventilation, preoperative variables evaluated and outcomes measured have differed between studies.

A major limitation of our analysis of pre-operative predictors is that intra-operative complications are known to have significant impact on post-operative morbidity and mortality [9]. To address this we have included in our analysis the use of IABP, CPB for greater than 120 min, post-operative MI, re-operation for bleeding and permanent stroke. The later three variables or complications were shown to be very strong independent predictors of prolonged ventilation regardless of pre-operative risk factors. Therefore our ability to predict who will require prolonged mechanical ventilation will always be greatly influenced by intra-operative outcomes. A potential weakness is also that we did not sensor mortality in our analysis. It is likely that patients that died within 24 h of surgery would have required prolonged ventilation, however, this represents only a small group of patients (n=16). Given the relatively large cohort evaluated (n=1829), the c statistic of the multiple logistic regression model predicting a good fit and the representativeness of the cohort, it is unlikely that our findings are inaccurate or biased.

In summary, we have demonstrated that in a large cohort of patient undergoing coronary revascularization it is possible to predict using pre-operative variables the risk of each individual patient to require prolonged mechanical ventilation expressed as a percent risk. Six independent predictors were identified and represent the framework of the predictive model. The ability to identify patients with increased risk for prolonged ventilation may allow the development of pre-emptive strategies and appropriate resource allocation.


   References
Top
 Abstract
 1. Introduction
 2. Materials and methods
 3. Results
 4. Discussion
 References
 

  1. Morris A., Almond D. Revascularization rates and waiting lists — An international perspective. Can J Cardiol 1997;13:53D-57D.
  2. Arom K.V., Emery R.W., Petersen R.J., Schwartz M. Cost-effectiveness and predictors of early extubation. Ann Thorac Surg 1995;60:127-132.[Abstract/Free Full Text]
  3. Konstantakos A.K., Lee J.H. Optimizing timing of early extubation in coronary artery bypass surgery patients. Ann Thorac Surg 2000;69:1842-1845.[Abstract/Free Full Text]
  4. Cheng D.C.H., Karski J., Peniston C., Asokumar B., Raveendran G., Carroll J., Nierenberg H., Roger S., Mickle D., Tong J., Zelovitsky J., David T., Sandler A. Morbidity outcome in early versus conventional tracheal extubation after coronary artery bypass grafting: a prospective randomized controlled trial. J Thorac Cardiovasc Surg 1996;112:755-764.[Abstract/Free Full Text]
  5. Fruitman D.S., MacDougall C.E., Ross D.B. Cardiac surgery in octogenarians: can elderly patients benefit? Quality of life after cardiac surgery. Ann Thorac Surg 1999;68:2129-2135.[Abstract/Free Full Text]
  6. Gass G.D., Olsen G.N. Preoperative pulmonary functional testing to predict postoperative morbidity and mortality. Chest 1986;89:127-135.[Free Full Text]
  7. Butler J., Chong G.L., Pillai R., Westaby S., Rocker G.M. Early extubation after coronary artery bypass surgery: effects on oxygen flux and hemodynamic variables. J Cardiovasc Surg 1992;33:276-280.[Medline]
  8. Gall S.A., Olsen C.O., Reves J.G., McIntyre R.W., Tyson G.S., Jr, Davis J.W., Rankin J.S. Beneficial effects of endotracheal extubation on ventricular performance. J Thorac Cardiovasc Surg 1988;95:819-827.[Abstract]
  9. Thompson M.J., Elton R.A., Mankad P.A., Campanella C., Walker W.S., Sang C.T., Cameron E.W. Prediction of requirement for, and outcome of, prolonged mechanical ventilation following cardiac surgery. Cardiovasc Surg 1997;5:376-381.[Medline]
  10. Spivack S.D., Shinozaki T., Albertini J.J., Deane R. Preoperative prediction of postoperative respiratory outcome. Chest 1996;109:1222-1230.[Abstract/Free Full Text]
  11. Hirsch G.M., Cha K.H., Buth K.J., Sullivan J.A. Independent preoperative predictors of prolonged length of stay following isolated CABG surgery: a prospective multivariable analysis of 1784 patients. Can J Cardiol 1998;14(Suppl):83F.
  12. Higgins T.L., Estafanous F.G., Loop F.D., Beck G.J., Blum J.M., Paranandi L. Stratification of morbidity and mortality outcome by preoperative risk factors in coronary artery bypass patients. J Am Med Assoc 1992;267:2344-2348.[Abstract/Free Full Text]
  13. Ghali W.A., Quan H., Brant R. Coronary artery bypass grafting in Canada: hospital mortality rates, 1992–1995. Can Med Assoc J 1998;159(8):926-930.[Abstract]
  14. Reyes A., Vega G., Blancas R., Morato B., Moreno J.L., Torrecilla C., Cereijo E. Early vs conventional extubation after cardiac surgery with cardiopulmonary bypass. Chest 1997;112:193-201.[Abstract/Free Full Text]
  15. Habib R.H., Zacharias A., Engoren M. Determinants of prolonged mechanical ventilation after coronary artery bypass grafting. Ann Thorac Surg 1996;62:1164-1171.[Abstract/Free Full Text]
  16. Kollef M.H., Wragge T., Pasque C. Determinants of mortality and multiorgan dysfunction in cardiac surgery patients requiring prolonged mechanical ventilation. Chest 1995;107:1395-1401.[Abstract/Free Full Text]
  17. Geraci J.M., Rosen A.K., Ash A.S., McNiff K.J., Moskowitz M.A. Predicting the occurrence of adverse events after coronary artery bypass surgery. Ann Intern Med 1993;118:18-24.[Abstract/Free Full Text]
  18. Silbert B.S., Santamaria J.D., O'Brien J.L., Blyth C.M., Kelly W.J., Molnar R.R. Early extubation following coronary artery bypass surgery. Chest 1998;113:1481-1488.[Abstract/Free Full Text]
  19. Adler D.S., Golman L., O'Neil A., Cook E.F., Mudge G.H., Jr, Shemin R.J., DiSesa V., Cohn L.H., Collins J.J., Jr Long-term survival of more than 2,000 patients after coronary artery bypass grafting. Am J Cardiol 1986;58:195-202.[Medline]
  20. Cosgrove D.M., Loop F.D., Lytle B.W., Gill C.C., Golding L.A., Gibson C., Stewart R.W., Taylor P.C., Goormastic M. Determinant of 10 year survival after primary myocardial revascularization. Ann Surg 1985;202:480.[Medline]
  21. Samuels L.E., Kaufman M.S., Morris R.J., Promisloff R., Brockman S.K. Coronary artery bypass grafting in patients with COPD. Chest 1998;113:878-882.[Abstract/Free Full Text]
  22. He G.W., Acuff T.E., Ryan W.H., He Y.H., Mack M.J. Influence of old age, gender, and internal mammary artery grafting on operative mortality and morbidity in coronary artery bypass grafting. Am J Geriatr Cardiol 1996;5:22-35.[Medline]
  23. Capdeville M., Lee J.H., Taylor A.L. Effect of gender on fast-track recovery after coronary artery bypass graft surgery. J Cardiothorac Vasc Anaesth 2001;15:146-151.[Medline]
  24. Salomon N.W., Page S., Bigelow J.C., Krause A.H., Okies J.E., Metzdorff M.T. Coronary artery bypass grafting in elderly patients. Comparative results in a consecutive series of 469 patients older than 75 years. J Thorac Cardiovasc Surg 1991;101:209-218.[Abstract]
  25. Hall R.J., Elayda M.A., Gray A., Mathur V.S., Garcia E., de Castro C.M., Massumi A., Cooley D.A. Coronary artery bypass: long-term follow-up of 22,284 consecutive patients. Circulation 1983;68(ii):20-26.



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Long-term outcome and quality of life of patients requiring prolonged mechanical ventilation after cardiac surgery
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Composite arterial grafts versus conventional grafting for coronary artery bypass grafting
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Angiographic coronary diffuseness and outcomes in dialysis patients undergoing coronary artery bypass grafting surgery
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ICU readmission after cardiac surgery
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