George Djaiani

The independent association of massive blood loss with mortality in cardiac surgery

BACKGROUND:  Although the association between massive perioperative blood loss (MBL) and adverse outcomes is well recognized, it is unclear whether MBL is an independent risk factor or, instead, simply a marker for other adverse events or severity of illness. The objective of this cohort study was to quantify the independent association of MBL in cardiac surgery with all‐cause in‐hospital mortality.

A Systematic Review of the Safety and Effectiveness of Fast-track Cardiac Anesthesia

COST containment and efficient resource use have forced anesthesiologists to rethink their management strategies for cardiac surgery. In the late 1970s, when anesthetic practice predominantly involved inhalational anesthesia, it was possible to extubate cardiac surgical patients within a few hours after surgery. However, there was no economic pressure or incentive to practice cost-effective medicine at that time. An opioid-based anesthetic regimen gained popularity in the 1980s, when studies confirmed its ability to allow hemodynamic stability, even in patients with marginal cardiac reserve. This necessitated continuation of postoperative ventilatory support for 12–24 h in cardiac surgical patients. The growing need for intensive cardiovascular and ventilatory support during the immediate postoperative period in these patients required an expansion of intensive care unit (ICU) bed availability. Until recently, this need for postoperative ICU nursing care and length of stay had continued unchecked. The aims of “fast-tracking” cardiac surgical patients include early tracheal extubation and decreased length of ICU and hospital stay with subsequent cost reduction. Fast-track cardiac anesthesia (FTCA) techniques include the use of short-acting hypnotic drugs, reduced doses of opioids, or the use of ultrashort-acting opioids, and, in some cases, the use of antifibrinolytic drugs or drugs to prevent atrial fibrillation. There are purported benefits of early tracheal extubation and reduced duration of mechanical ventilation. Several randomized trials have found that early tracheal extubation can be safely achieved, and it may lead to reduced ICU stay and costs. Despite these findings, there are residual concerns regarding early tracheal extubation and FTCA. Studies to date have not included a sufficient number of patients to detect a clinically important effect on serious morbidity or mortality. The primary objective of this systematic review was to determine whether FTCA is as safe as traditional cardiac anesthesia (TCA) based on the administration of high doses of opioids. The hypothesis tested was that there is not an increased risk of mortality or major morbidity associated with FTCA compared with TCA.

Preoperative use of statins is associated with reduced early delirium rates after cardiac surgery.

Background:Delirium is an acute deterioration of brain function characterized by fluctuating consciousness and an inability to maintain attention. Use of statins has been shown to decrease morbidity and mortality after major surgical procedures. The objective of this study was to determine an association between preoperative administration of statins and postoperative delirium in a large prospective cohort of patients undergoing cardiac surgery with cardiopulmonary bypass. Methods:After Institutional Review Board approval, data were prospectively collected on consecutive patients undergoing cardiac surgery with cardiopulmonary bypass from April 2005 to June 2006 in an academic hospital. All patients were screened for delirium during their hospitalization using the Confusion Assessment Method in the intensive care unit. Multivariable logistic regression analysis was used to identify independent perioperative predictors of delirium after cardiac surgery. Statins were tested for a potential protective effect. Results:Of the 1,059 patients analyzed, 122 patients (11.5%) had delirium at any time during their cardiovascular intensive care unit stay. Administration of statins had a protective effect, reducing the odds of delirium by 46%. Independent predictors of postoperative delirium included older age, preoperative depression, preoperative renal dysfunction, complex cardiac surgery, perioperative intraaortic balloon pump support, and massive blood transfusion. The model was reliable (Hosmer-Lemeshow test, P = 0.3) and discriminative (area under receiver operating characteristic curve = 0.77). Conclusions:Preoperative administration of statins is associated with the reduced risk of postoperative delirium after cardiac surgery with cardiopulmonary bypass.

Continuous-Flow Cell Saver Reduces Cognitive Decline in Elderly Patients After Coronary Bypass Surgery

Background— Cerebral microembolization during cardiopulmonary bypass may lead to cognitive decline after cardiac surgery. Transfusion of the unprocessed shed blood (major source of lipid microparticulates) into the patient during cardiopulmonary bypass is common practice to reduce blood loss and blood transfusion. Processing of shed blood with cell saver before transfusion may limit cerebral microembolization and reduce cognitive decline after surgery. Methods and Results— A total of 226 elderly patients were randomly allocated to either cell saver or control groups. Anesthesia and surgical management were standardized. Epiaortic scanning of the proximal thoracic aorta was performed in all patients. Transcranial Doppler was used to measure cerebral embolic rates. Standardized neuropsychological testing was conducted 1 week before and 6 weeks after surgery. The raw scores for each test were converted to Z scores, and then a combined Z score of 10 main variables was calculated for both study groups. The primary analysis was based on dichotomous composite cognitive outcome with a 1-SD rule. Cognitive dysfunction was present in 6% (95% confidence interval, 1.3% to 10.7%) of patients in the cell saver group and 15% (95% confidence interval, 8% to 22%) of patients in the control group 6 weeks after surgery (P=0.038). The severity of aortic atheroma and cerebral embolic count were similar between the 2 groups. Conclusions— The present report demonstrates that processing of shed blood with cell saver results in clinically significant reduction in postoperative cognitive dysfunction after cardiac surgery. These findings emphasize the clinical importance of lipid embolization in contributing to postoperative cognitive decline in patients exposed to cardiopulmonary bypass.

Mild to Moderate Atheromatous Disease of the Thoracic Aorta and New Ischemic Brain Lesions After Conventional Coronary Artery Bypass Graft Surgery

Background and Purpose— The presence of new ischemic brain infarcts, detected by diffusion-weighted magnetic resonance imaging (DW-MRI), have been reported in considerable number of patients after cardiac surgery. We sought to determine the role of proximal thoracic aortic atheroma in predicting embolic events and new ischemic brain lesions in patients undergoing conventional coronary revascularization surgery. Methods— Transesophageal echocardiography and epiaortic scanning was performed to assess the severity of aortic atherosclerosis in the ascending aorta and the aortic arch. Patients were allocated to either low-risk group, (intimal thickness ≤2mm), or high-risk group (intimal thickness >2mm). Transcranial Doppler was used to monitor the middle cerebral artery. DW-MRI was performed 3–7 days after surgery. The NEECHAM Confusion Scale was used for assessment and monitoring patient consciousness level. Results— Patients in the high-risk group were considerably older; 71±6 (n=38) versus 67±6 (n=72) years, P =0.004 and were more likely to have impaired left ventricular function. Confusion was present in 6 (16%) patients in the high-risk group and 5 (7%) patients in the low-risk group. Patients in the high-risk group had a three-fold increase in median embolic count, 223.5 versus 70.0, P =0.0003. DW-MRI detected brain lesions were only present in patients from high-risk group, 61.5 versus 0%, P <0.0001. There was significant correlation between the NEECHAM scores and embolic count in the high-risk group; r=0.63, P <0.001. Conclusions— The findings of this investigation suggest that mild to moderate atheromatous disease of the ascending aorta and the aortic arch (intimal thickness >2mm) is a major contributor to ischemic brain injury after cardiac surgery.

Randomized assessment of resource use in Fast-track cardiac surgery 1-year after hospital discharge

Background The authors assessed the safety and resource use associated with fast-track cardiac anesthesia (FTCA) after coronary artery bypass graft surgery (CABG) over a 1-yr period. Methods One hundred twenty patients were initially randomized to FTCA (n = 60) or conventional anesthetic (n = 60) for primary elective CABG surgery. Patients were followed for 1-yr after index surgery through linkage to universal administrative databases. Acute care hospital readmission rates and length of stay (LOS) and the downstream use of health resources were compared. Resource use was analyzed as use of hospital and rehabilitation center bed-days, expenditures on physician services, and use of cardiac drugs. Results There were no deaths during the 1-yr follow-up after initial discharge; 15 (25%) patients from both groups were readmitted to acute care hospitals in the follow-up period. The mean LOS for acute care readmission was 0.3 (1.0) in the FTCA and 1.6 (6.3) days in the conventional group at 3 months;P = 0.01, 95% CI (0.1, 5.7) and 0.8 (1.8) and 2.9 (9.6) days at 12 months;P = 0.01, 95% CI (0.2, 7.5). Two (3.3%) patients in the FTCA group and 9 (15%) patients in the conventional group were transferred to rehabilitation facilities. The LOS was 0.3 (1.5) and 2.3 (5.7) days respectively;P = 0.001, 95% CI (0.6, 4.0). Specialist visits were more frequent in the FTCA group 6.2 (13.2) versus 1.9 (2.2) visits respectively;P = 0.002, 95% CI (−9.0, −1.3). Percentage reduction of FTCA cost was 68% at 3 months, P = 0.0002 and 49.5% at 1-yr, P = 0.004 after index hospital discharge. Conclusions Fast-track cardiac anesthesia is a safe practice that decreases resource use for a 1-yr period after index hospitalization.

Mobile phones in the hospital – past, present and future

Summary The phenomenon of electromagnetic interference by mobile phones is real and potentially clinically significant. This has been recognised by the Department of Health and the Medical Devices Agency, leading to bans on phone use in hospitals. Current evidence suggests that mobile phones can cause malfunction of medical equipment, but only when used in close proximity. Allowing phone use in non‐patient care areas and improving staff education may improve compliance with hospital policies.

Epiaortic Scanning Modifies Planned Intraoperative Surgical Management But Not Cerebral Embolic Load During Coronary Artery Bypass Surgery

BACKGROUND:Patients with aortic atheroma are at increased risk for neurological injury after coronary artery bypass graft (CABG) surgery. We sought to determine the role of epiaortic ultrasound scanning for reducing cerebral embolic load, and whether its use leads to changes of planned intraoperative surgical management in patients undergoing CABG surgery. METHODS:Patients >70-yr-of-age scheduled for CABG surgery were prospectively randomized to either an epiaortic scanning (EAS) group (aortic manipulation guided by epiaortic ultrasound) or a control group (manual aortic palpation without EAS). All patients received a comprehensive transesophageal echocardiographic examination. Transcranial Doppler (TCD) was used to monitor the middle cerebral arteries for emboli continuously from 2 min before aortic cannulation to 2 min after aortic decannulation. Neurological assessment was performed with the National Institute of Health stroke scale before surgery and at hospital discharge. The NEECHAM confusion scale was used for assessment and monitoring of patient global cognitive function on each day after surgery until hospital discharge. RESULTS:Intraoperative surgical management was changed in 16 of 55 (29%) patients in the EAS group and in 7 of 58 (12%) patients in the control group (P = 0.025). These changes included adjustments of the ascending aorta cannulation site for cardiopulmonary bypass (CPB), the avoidance of aortic cross-clamping by using ventricular fibrillatory arrest during surgery, or by conversion to off-pump surgery. During surgery, 7 of 58 (12%) patients in the control group crossed over to the EAS group based on the results of manual aortic palpation. The median [range] TCD detected cerebral embolic count did not differ between the EAS and control groups during aortic manipulations (EAS, 11.5 [1–516] vs control, 22.0 [1–160], P = 0.91) or during CPB (EAS, 42.0 [4–516] vs control, 63.0 [5–758], P = 0.46). The NEECHAM confusion scores and National Institute of Health stroke scale scores were similar between the two groups. CONCLUSIONS:These results show that the use of EAS led to modifications in intraoperative surgical management in almost one-third of patients undergoing CABG surgery. The use of EAS did not lead to a reduced number of TCD-detected cerebral emboli before or during CPB.

Aortic Arch Atheroma: Stroke Reduction in Cardiac Surgical Patients

Cardiac surgery is increasingly performed on elderly patients with extensive coronary artery abnormalities who have impaired left ventricular function, decreased physiologic reserve, and multiple comorbid conditions. Considerable numbers of these patients develop perioperative neurologic complications ranging from subtle cognitive dysfunction to more evident postoperative confusion, delirium, and, less commonly, clinically apparent stroke. Magnetic resonance imaging studies have elucidated that a considerable number of patients have new ischemic brain infarcts, particularly after conventional coronary artery bypass graft surgery. Mechanisms of cerebral injury during and after cardiac surgery are discussed. Intraoperative transesophageal echocardiography and epiaortic scanning for detection of atheromatous disease of the proximal thoracic aorta is paramount in identifying patients at high risk from neurologic injury. It is important to recognize that our efforts to minimize neurologic injury should not be limited to the intraoperative period. Particular efforts should be directed to temperature management, glycemia control, and pharmacologic neuroprotection extending into the postoperative period. Preoperative magnetic resonance angiography may be of value for screening patients with significant atheroma of the proximal thoracic aorta. It is likely that for patients with no significant atheromatous disease, conventional coronary artery revascularization is the most effective long-term strategy, whereas patients with atheromatous thoracic aorta may be better managed with beating heart surgery, hybrid techniques, or medical therapy alone. Patient stratification based on the aortic atheromatic burden should be addressed in future trials designed to tailor treatment strategies to improve long-term outcomes of coronary heart disease and reduce the risks of perioperative neurologic injury.

Fast-track cardiac anesthesia in patients with sickle cell abnormalities

UNLABELLED: We conducted a retrospective review of 10 patients with sickle cell trait (SCT) and 30 patients (cohort control) without SCT undergoing first-time coronary artery bypass graft surgery with cardiopulmonary bypass. Demographic, perioperative management, and outcome data were collected. Both groups were matched according to age, weight, duration of surgery, and preoperative hemoglobin (Hb) concentration. Distribution of gender, medical conditions, pharmacological treatment, and preoperative left ventricular function were similar between the groups. The comparisons were analyzed in respect to postoperative blood loss and transfusion rates, as well as duration of intubation, intensive care unit, and hospital length of stay (LOS). All patients underwent fast-track cardiac anesthesia. A combination of cold crystalloid and blood cardioplegia was used. The lowest nasopharyngeal temperature was 33 degrees C. There were no episodes of significant hypoxemia, hypercarbia, or acidosis. None of the patients had sickling crisis during the perioperative period. The postoperative blood loss was 687 +/- 135 vs 585 +/-220 mL in the SCT and control groups, respectively. The trigger for blood transfusion during cardiopulmonary bypass was hematocrit <20% and Hb <75 g/L postoperatively. Three SCT patients (30%) and 10 control patients (33%) received a blood transfusion. Median extubation time was 4.0 vs 3.9 h; intensive care unit LOS was 27 vs 28 h; and hospital LOS was 6.0 vs 5.5 days in the SCT and control groups, respectively. There were no intraoperative deaths. One patient in the SCT group died from multiorgan failure 2 mo after surgery. IMPLICATIONS: Fast-track cardiac anesthesia can be used safely in patients with sickle cell trait undergoing first-time coronary artery bypass graft surgery. Extubation time and intensive care unit and hospital length of stay are comparable to those of matched controls, and blood loss and transfusion requirements are not increased. A hematocrit of 20% seems to be a safe transfusion trigger during cardiopulmonary bypass in these patients.