Safety and efficacy of early extubation of elderly coronary artery bypass surgery patients

Balancing intubation time with postoperative risk in cardiac surgery patients - a retrospective cohort analysis

Introduction

Intubation time in patients undergoing cardiac surgery may be associated with increased mortality and morbidity. Premature extubation can have serious adverse physiological consequences. The aim of this study was to determine the influence of intubation time on morbidity and mortality in patients undergoing cardiac surgery.

Methods

We performed a retrospective analysis of data on 1,904 patients undergoing isolated coronary artery bypass grafting (CABG) and stratified them by duration of intubation time after surgery - 0-6, 6-9, 9-12, 12-24 and over 24 hours. Postoperative complications risk analysis was performed using multivariate logistic regression analysis for patients extubated ≤12 and >12 hours.

Results

Intubation percentages in each time cohort were as follows: 0-6 hours - 7.8%, 6-9 hours - 17.3%, 9-12 hours - 26.8%, 12-24 hours - 44.4% and >24 hours - 3.7%. Patients extubated ≤12 hours after CABG were younger, mostly males, more often smokers, with lower preoperative risk. They had lower 30-day mortality (2.02% vs 4.59%, P=0.002), shorter hospital stay (7.68±4.49 vs 9.65±12.63 days, P<0.001) and shorter intensive care unit stay (2.39 vs 3.30 days, P<0.001). Multivariate analysis showed that intubation exceeding 12 hours after CABG increases the risk of postoperative delirium (OR 1.548, 95% CI 1.161-2.064, P=0.003) and risk of postoperative hemofiltration (OR 1.302, 95% CI 1.023-1.657, P=0.032).

Conclusion

Results indicate that risk of postoperative complications does not increase until intubation time exceeds 12 hours. Shorter intubation time is seen in younger, men and smokers. Intubation time >12 hours is a risk factor for postoperative delirium and hemofiltration after cardiac surgery.

Routine operation theatre extubation after cardiac surgery in the elderly

OBJECTIVES

The aim was to analyse in-hospital outcomes of patients over 70 years of age undergoing routine immediate operation theatre (OT) extubation after on-pump or off-pump cardiac surgery.

METHODS

A retrospective analysis was performed of prospectively collected data over a 4-year period (2011-14) from elderly patients undergoing early extubation after cardiac surgery at a single institution. All patients over 70 years were considered eligible for immediate OT or intensive care unit (ICU) early extubation after meeting specific criteria. All types of non-emergency cardiac surgery were included. Cardiac surgical risk stratification was assessed with EuroSCORE II and age, creatinine level and left ventricular ejection fraction (ACEF) score.

RESULTS

Among the 415 patients operated on during the period, 275 (66.3%) were ≥70 years old. One hundred and forty patients (50.9%) of the elderly group were extubated successfully in the OT. Excluding off-pump coronary surgery, OT extubation was achieved in 51.5% of cases. The rate of risk of reintubation within 24 h of surgery after OT extubation was 2.1%. The in-hospital mortality rate was 4.7%, and the complication rate was 11.6%, independently of extubation timing. Elderly patients extubated in the OT had a significantly lower median EuroSCORE II risk level and ACEF score, more isolated valve surgeries, reduced cardiopulmonary bypass time, less complications and shorter length of stay than ICU-extubated patients. In the multivariate analysis, only the ACEF score remained as an independent variable associated with OT extubation in the elderly (odds ratio 25.0, 95% CI 2.74-228.8, P = 0.004), and had good discriminating power [receiver operating characteristics (ROC) area 0.713]. On the other hand, the EuroSCORE ROC area used to predict OT extubation was 0.694, and the cut-off analysis showed that a risk value under 2.11 was associated with 72.1% OT extubation versus 37.3% when the risk value was over 2.11 (P = 0.0002).

CONCLUSIONS

OT extubation in the elderly can be safely performed in nearly 50% of patients, without apparently worsening their outcomes. A key point of this success was the use of a short-acting volatile agent to maintain anaesthesia throughout the procedure. Low- or moderate-risk cardiac surgery assessed with a preoperative EuroSCORE II <2.11 will help to better predict successful OT extubation in the elderly.

Risk factors for late extubation after coronary artery bypass grafting

OBJECTIVE

To evaluate the independent risk factors for late extubation after coronary artery bypass grafting (CABG).

METHODS

Preoperative, intraoperative, and postoperative characteristics of patients undergoing isolated CABG between June 2005 and June 2008 at the Tongji Hospital were retrospectively analyzed. Elapsed time between CABG and extubation of more than 8hours was defined as late extubation.

RESULTS

The incidence of late extubation after CABG was 69.23% (288/416). Through univariate and logistic regression analysis, the independent risk factors for late extubation after CABG were older age (odds ratio [OR]=4.804), duration of cardiopulmonary bypass (OR=2.426), perioperative use of intra-aortic balloon pump (OR=1.451), preoperative arterial oxygen partial pressure (OR=.204), and postoperative hemoglobin level (OR=.793).

CONCLUSION

Older age, prolonged cardiopulmonary bypass time, perioperative intra-aortic balloon pump requirement, low preoperative arterial oxygen partial pressure, and low postoperative hemoglobin level were identified as the 5 independent risk factors for late extubation after CABG.

Increasing healthcare resource utilization after coronary artery bypass graft surgery in the United States

BACKGROUND

Despite declining lengths of stay, postdischarge healthcare resource utilization may be increasing because of shifts to nonacute care settings. Although changes in hospital stay after coronary artery bypass graft (CABG) surgery have been described, patterns of discharge remain unclear. Our objective was to determine patterns of discharge disposition after CABG surgery in the United States.

METHODS AND RESULTS

We examined discharge disposition after CABG procedures from 1988 to 2005 using the Nationwide Inpatient Sample. Discharges with a "nonroutine" disposition defined patients discharged with continued healthcare needs. Multivariable regression models were constructed to assess trends and factors associated with nonroutine discharge. Median length of stay among 8,398,554 discharges decreased from 11 to 8 days between 1988 and 2005 (P<0.0001). There was a simultaneous increase in nonroutine discharges from 12% in 1988 to 45% in 2005 (P<0.0001), primarily comprising home healthcare and long-term facility use. Multivariable regression models showed age, female gender, comorbidities, concurrent valve surgery, and lower-volume hospitals more likely to be associated with nonroutine discharge.

CONCLUSIONS

We found a significant increase in nonroutine discharges after CABG surgery across the United States from 1988 to 2005. The significant shortening of length of stay during CABG may be counterbalanced by the increased requirement for additional postoperative healthcare services. Nonacute care institutions are playing an increasingly significant role in providing CABG patients with postdischarge healthcare and should be considered in investigations of postoperative healthcare resource utilization. The impact of these changes on long-term outcomes and net resource utilization remain unknown.

Influence of fast-track recovery after coronary artery bypass in the elderly

We retrospectively analyzed 711 consecutive patients who had isolated coronary artery bypass grafting between January 2000 and December 2004; 572 younger patients (< 70 years) were compared with 139 elderly patients (> or = 70 years). A rapid recovery program based on an anesthetic protocol for early extubation was applied to all patients. The overall hospital mortality rate was 3.3% for the younger group and 4.3% for the elderly group. There were no significant differences in rates of hospital mortality and postoperative complications between the two groups. Early extubation was achieved in significantly more younger (71%) compared to elderly (57%) patients. Rapid recovery with discharge before the 5(th) postoperative day was achieved in 19% of the elderly compared to 48% of the younger patients. Patients in the younger group were discharged from hospital earlier (6.8 +/- 0.3 vs 8.0 +/- 8.5 days). Application of fast-track treatment in an elderly population appears to be a safe and effective approach if used on a selective basis when criteria for early extubation are met.

Caring for Octogenarian Coronary Artery Bypass Graft Patients at Home

Rates of coronary artery bypass graft (CABG) surgery on octogenarians have been rising by more than 15% each year since the mid-1980s. Little is known about the experience of caring for this select group of patients at home after discharge. The purpose of this study was to describe the lived experience of caring for very elderly (80 years or older) CABG patients during convalescence at home. Using hermeneutic/phenomenological methods, 12 family caregivers were interviewed at home during the 4-week postdischarge period. Analysis of data derived from interviews revealed that work, personal reaction to caregiving, and experiences with formal care were recurrent themes. Caregivers indicated through their stories that caring for a recovering octogenarian at home after CABG surgery entailed a great deal of work that moderated at about 4 weeks after discharge. The caregivers also described varied reactions, both emotional and pragmatic, as the weeks unfolded. In addition, the data revealed a range of experiences, positive and negative, with healthcare providers and facilities. The study findings indicate a need for improvements in the following areas: preoperative, postoperative, and discharge education for family members involved in the care of the elderly CABG patient, and communication within and between healthcare organizations with regard to discharge planning.

Fast-Track Recovery in Noncoronary Cardiac Surgery Patients

Objective: Fast-track recovery protocols result in shorter hospital stays and decreased costs in coronary artery bypass grafting (CABG) surgery. However, data based on an objective scoring system are lacking for the impact of these protocols on patients undergoing cardiac surgery other than isolated CABG. Methods: Between March 1999 and March 2003, 299 consecutive patients who underwent open cardiac surgery other than isolated CABG were analyzed to evaluate the safety and efficacy of fast-track recovery. The parameters evaluated as predictors of mortality, ie, delayed extubation (>360 minutes), intensive care unit (ICU) discharge (>24 hours), increased length of hospital stay (>5 days), and red blood cell transfusion, were determined by regression analysis. Standard perioperative data were collected prospectively for every patient. Results: Seventy-two percent of the patients were extubated within 6 hours, 87% were discharged from the ICU within 24 hours, and 60% were discharged from the hospital within 5 days. No red blood cells were transfused in 67% of the patients. There were no predictors of mortality. The predictors of delayed extubation were preoperative congestive heart failure (P = .005; odds ratio [OR], 4.5; 95% confidence interval [CI], 1.6-12.6) and peripheral vascular disease (P = .02; OR, 6; 95% CI, 1.9-19.4). Factors leading to increased ICU stay were diabetes (P = .05; OR, 3.6; 95% CI, 1-12.6), emergent operation (P = .04; OR, 6.1; 95% CI, 1.1-33.2), red blood cell transfusion (P = .03; OR, 2.9; 95% CI, 1.1-7.8), chest tube drainage >1000 mL (P = .03; OR, 3.4; 95% CI, 1.1-10.2). The predictors of increased length of hospital stay were ICU stay >24 hours (P = .001; OR, 5.9; 95% CI, 2-17), EuroSCORE >5 (P = .05; OR, 1.8; 95% CI, 1-3.2), and chronic obstructive pulmonary disease (P = .003; OR, 3.7; 95% CI, 1.5-8.7). Predictive factors for transfusion of red blood cells were diabetes (P = .04; OR, 2.9; 95% CI, 1.1-8.1), delayed extubation (P = .02; OR, 2.7; 95% CI, 1.4-5.1), increased ICU stay (P = .04; OR, 2.6; 95% CI, 1-6.4), and chest tube drainage >1000 mL (P = .001; OR, 4.3; 95% CI, 2-9.3). Conclusions: This study confirms the safety and efficacy of the fast-track recovery protocol in patients undergoing open cardiac surgery other than isolated CABG.

Outcomes of early extubation after bypass surgery in the elderly

BACKGROUND

While early extubation after coronary artery bypass grafting (CABG) has been associated with resource savings, its effect on patient outcomes remains unclear. The goal of the present investigation was to evaluate whether early extubation can be performed safely in elderly CABG patients in community practice.

METHODS

We studied 6,446 CABG patients, aged 65 years and older, treated at 35 hospitals between 1995 and 1998. Patients were categorized based on their post-CABG extubation duration (early, < 6 hours; intermediate, 6 to < 12 hours; and late, 12 to 24 hours). We compared unadjusted and risk-adjusted mortality, reintubation rates, and post-CABG length of stay (pLOS). We also examined the association between patients' intubation time and outcomes among patients with similar propensity for early extubation and among high-risk patient subgroups.

RESULTS

The overall mean post-CABG intubation time was 9.8 (SD 5.7) hours with 29% of patients extubated within 6 hours. After adjusting for preoperative risk factors patients extubated in less than 6 hours had significantly shorter postoperative hospital stays than those with later extubation times. Patients extubated early also tended to have equal or better risk-adjusted mortality than those with intermediate (odds ratio: 1.69, p = 0.08) or long intubation times (odds ratio: 1.97, p = 0.02). These results were consistent among patients with similar preoperative propensity for early extubation and among important high-risk patient subgroups. There was no evidence for higher reintubation rates among elderly patients selected for early extubation.

CONCLUSIONS

In community practice, early extubation after CABG can be achieved safely in selected elderly patients. This practice was associated with shorter hospital stays without adverse impact on postoperative outcomes.

Alabama coronary artery bypass grafting project: results from phase II of a statewide quality improvement initiative

OBJECTIVE/BACKGROUND

This report describes the first round of results for Phase II of the Alabama CABG Project, a regional quality improvement initiative.

METHODS

Charts submitted by all hospitals in Alabama performing CABG (ICD-9 codes 36.10-36.20) were reviewed by a Clinical Data Abstraction Center (CDAC) (preintervention 1999-2000; postintervention 2000-2001). Variables that described quality in Phase I were abstracted for Phase II and data describing the new variables of beta-blocker use and lipid management were collected. Data samples collected onsite by participating hospitals were used for rapid cycle improvement in Phase II.

RESULTS

CDAC data (n = 1927 cases in 1999; n = 2001 cases in 2000) showed that improvements from Phase I in aspirin prescription, internal mammary artery use, and duration of intubation persisted in Phase II. During Phase II, use of beta-blockers before, during, or after CABG increased from 65% to 76% of patients (P < 0.05). Appropriate lipid management, an aggregate variable, occurred in 91% of patients before and 91% after the educational intervention. However, there were improvements in 3 of 5 subcategories for lipid management (documenting a lipid disorder [52%-57%], initiating drug therapy [45%-53%], and dietary counseling [74%-91%]; P < 0.05).

CONCLUSIONS

In Phase II, this statewide process-oriented quality improvement program added two new measures of quality. Achievements of quality improvement from Phase I persisted in Phase II, and improvements were seen in the new variables of lipid management and perioperative use of beta-blockers.

Early extubation for adult cardiac surgical patients

BACKGROUND

Over 30 studies reported that early extubation (within eight hours) appears to be safe without an increased incidence of morbidity. A benefit of the practice may be cost savings associated with shorter Intensive Care Unit and hospital length of stays.

OBJECTIVES

To assess the effects of early extubation and the impact of the extubating clinician's profession on morbidity, mortality, intensive care unit and hospital length of stay, with a subgroup analysis for extubation within four hours or four to eight hours.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL)(issue 1, 2003), MEDLINE (January 1966 to June 2003), EMBASE (January 1980 to June 2003), CINAHL (January 1982 to December 2002), SIGLE(January 1980 to December 2002). We searched reference lists of articles and contacted researchers in the field.

SELECTION CRITERIA

Randomized controlled trials and controlled clinical trials of adult cardiac surgical patients (coronary artery bypass grafts, aortic valve replacement, mitral valve replacement, aortic aneurysm repair).

DATA COLLECTION AND ANALYSIS

Two reviewers independently assessed trial quality and extracted data. Study authors were contacted for additional information. A meta-analysis for most outcomes was conducted.

MAIN RESULTS

Six trials were included in the review. There was no evidence of a difference between early and conventionally extubated patients shown in the relative risk and 95% confidence interval for the following outcomes: mortality in intensive care was 0.8 (0.42 to 1.52); thirty day mortality was 1.2 (0.63 to 2.27); myocardial ischaemia was 0.96 (0.71 to 1.30); reintubation within 24 hours of surgery was 5.93 (0.72 to 49.14). Time spent in intensive care and in hospital were significantly shorter for patients extubated early (7.02 hours (- 7.42 to - 6.61) and 1.08 days ( - 1.35 to - 0.82) respectively).

REVIEWER'S CONCLUSIONS

There is no evidence of a difference in mortality and morbidity rates between the study groups. Early extubation reduces intensive care unit and hospital length of stay. Studies were underpowered and designed to show differences between study groups rather than equivalence between the groups. Suggested future areas of investigation: establishing the safety and efficacy of immediate extubation compared with early extubation; establishing the most effective means of pain control and reducing anxiety for patients; systematic reviews of the evidence for different parts of the patients journey through a cardiac surgery episode; and the impact of the profession of the clinician making the decision to extubate.

Postoperative pulmonary function in coronary artery bypass graft surgery patients undergoing early tracheal extubation: a comparison between short-term mechanical ventilation and early extubation

OBJECTIVE

To evaluate the effect of a short period of mechanical ventilation (3 hours) versus immediate extubation (within 1 hour of surgery) on pulmonary function, gas exchange, and pulmonary complications after coronary artery bypass graft (CABG) surgery.

DESIGN

Prospective randomized study.

SETTING

University teaching hospital.

PARTICIPANTS

Thirty-five patients undergoing CABG surgery.

INTERVENTIONS

Patients were randomized into 2 groups. Patients in group I were extubated as soon as possible after surgery. Patients in group II were ventilated for a minimum of 3 hours after surgery. Patients in both groups were extubated only after achieving predetermined extubation criteria. Patients who did not meet the criteria for extubation within the predetermined set time limit (90 minutes in group I and 6 hours in group II) were withdrawn from the study. Pulmonary function tests (vital capacity, forced expiratory volume in 1 second, total lung capacity, functional residual capacity), arterial blood gases, and chest radiographs were done preoperatively and postoperatively. Pulmonary complications were recorded.

MEASUREMENTS AND MAIN RESULTS

Demographic data were similar between groups. The mean time to extubation in group I was 45.7 plus minus 27.6 minutes and in group II was 201.4 plus minus 21 minutes (p < 0.01). Two patients in group I and 1 patient in group II did not meet the extubation criteria within the predetermined set time limit and were excluded from the study. In both groups, there was a significant decline in pulmonary function but no differences between groups at 24 or 72 hours after surgery. There were no differences between groups in blood gases, atelectasis scores, or pulmonary complications.

CONCLUSION

The data suggest that extending mechanical ventilation after CABG surgery does not affect pulmonary function. Provided that routine extubation criteria are met, patients can be safely extubated early (within 1 hour) after major cardiac surgery without concerns of further pulmonary derangement.

Effect of gender on fast-track recovery after coronary artery bypass graft surgery

OBJECTIVE

To examine the effects of gender on time to extubation after coronary artery bypass graft (CABG) surgery and intensive care unit and hospital length of stay.

DESIGN

Retrospective study comparing outcomes as related to gender.

SETTING

Tertiary care university teaching hospital.

PARTICIPANTS

Consecutive patients (n = 561; 376 men, 185 women) undergoing CABG surgery between January 1995 and December 1997.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Early extubation was possible in 74% of men versus 64% of women (p = 0.03); length of stay was < or =5 days in 60% of men versus 48% of women (p = 0.008); overall postoperative length of stay was 5.7 days for men versus 6.5 days for women (p = 0.003); morbidity and mortality were not significantly different between groups.

CONCLUSION

Women undergoing CABG surgery with a standardized fast-track protocol have longer intubation times, intensive care unit length of stay, and hospital length of stay than their male counterparts.

Desflurane pharmacokinetics during cardiopulmonary bypass

OBJECTIVE

To describe the washin and washout of desflurane when first administered during cardiopulmonary bypass (CPB) for cardiac surgery.

DESIGN

A single-arm prospective study.

SETTING

University-affiliated hospital operating room.

PARTICIPANTS

Ten adult patients presenting for cardiac surgery.

INTERVENTIONS

Consenting patients presenting for cardiac surgery received anesthesia with midazolam and fentanyl. Patients were cooled to 32 degrees C on CPB, then desflurane 6% was administered and blood samples drawn repeatedly from the arterial and venous bypass cannulae as well as from the membrane oxygenator inlet and exhaust from 2 to 32 minutes of desflurane administration. Just before rewarming, final (maximum) washin samples were taken. On rewarming, desflurane was discontinued, and blood and gas samples were taken 2 to 24 minutes thereafter.

MEASUREMENTS AND MAIN RESULTS

CPB time was 116 +/- 10 minutes, and ischemic time was 81 +/- 6 minutes. Mean pump flow was 4.49 +/- 0.03 L/min, and mean arterial pressure was 70.1 +/- 1 mmHg during the study period. Arterial washin of desflurane was initially rapid; arterial concentrations reached 50% of administered concentrations within 4 minutes, but then slowed, reaching 68% of inspired concentrations at 32 minutes (desflurane concentration 4.0% +/- 0.3%). Arterial washout of desflurane was more rapid; arterial concentrations fell to 18% of the maximum concentration reached within 4 minutes, and only 8% of the maximum arterial concentration was present in blood 20 minutes later.

CONCLUSION

Desflurane showed rapid initial washin and washout on CPB when administration was started at 32 degrees C and stopped at time of rewarming.

Optimizing timing of early extubation in coronary artery bypass surgery patients

BACKGROUND

This study was designed to assess the safety and efficacy of extubation performed within 4 hours of the patient's arrival in the surgical intensive care unit after coronary artery bypass graft surgery.

METHODS

A matched retrospective cohort study was performed including 412 consecutive patients undergoing isolated coronary artery bypass graft surgery between January 1996 and December 1997, constituting the experience of a single surgeon (J.H.L.). Early extubation (defined as extubation within 8 hours of arrival at the surgical intensive care unit) was achieved in 308 of 412 patients (75%). Patients extubated in fewer than 4 hours after arrival (n = 200) were compared with patients extubated within 4 to 8 hours (n = 108).

RESULTS

Four deaths occurred in 412 patients, for an overall operative mortality rate of 1.0%. Patients extubated in fewer than 4 hours were younger than those extubated 4 or more hours after admission (62 versus 67 years old, respectively; p = 0.001), more likely to be male (74% versus 63%, p < 0.05), and had shorter aortic cross-clamp times (49.4 +/- 15.0 versus 53.5 +/- 14.0 minutes, p < 0.05) and cardiopulmonary bypass (CPB) times (65.2 +/- 18.6 versus 72.1 +/- 19.1 minutes, p < 0.05) compared to patients extubated later. Moreover, patients extubated in fewer than 4 hours had a shorter surgical intensive care unit length of stay (33.8 +/- 25.7 versus 43.1 +/- 43.0 hours, p < 0.05) and shorter postoperative length of stay (5.4 +/- 2.4 versus 6.2 +/- 2.6 days, p = 0.01) than those extubated later.

CONCLUSIONS

Extubation in fewer than 4 hours may offer a substantial advantage in terms of accelerated recovery compared with extubation within 4 to 8 hours. Very few differences in clinical parameters were noted between the two groups we studied, suggesting that efforts to reduce extubation times further might be worthwhile.