Sweeta D. Gandhi

Ketamine Attenuates Delirium After Cardiac Surgery With Cardiopulmonary Bypass

OBJECTIVE To determine if ketamine attenuates postoperative delirium concomitant with an anti-inflammatory effect in patients undergoing cardiac surgery using cardiopulmonary bypass. DESIGN A prospective randomized study. SETTING A Veterans Affairs medical center. PARTICIPANTS Cardiac surgical patients. INTERVENTIONS Patients at least 55 years of age randomly received placebo (0.9% saline, n = 29) or an intravenous bolus of ketamine (0.5 mg/kg intravenously, n = 29) during anesthetic induction in the presence of fentanyl and etomidate. MEASUREMENTS AND MAIN RESULTS Delirium was assessed by using the Intensive Care Delirium Screening Checklist before and after surgery. Serum C-reactive protein concentrations were determined before and 1 day after surgery. The incidence of postoperative delirium was lower (p = 0.01, Fisher exact test) in patients receiving ketamine (3%) compared with placebo (31%). Postoperative C-reactive protein concentration was also lower (p < 0.05) in the ketamine-treated patients compared with the placebo-treated patients. The odds of developing postoperative delirium were greater for patients receiving placebo compared with ketamine treatment (odds ratio = 12.6; 95% confidence interval, 1.5-107.5; logistic regression). CONCLUSIONS After cardiac surgery using cardiopulmonary bypass, ketamine attenuates postoperative delirium concomitant with an anti-inflammatory effect.

Volume replacement therapy during major orthopedic surgery using Voluven® (Hydroxyethyl starch 130/0.4) or hetastarch

Background:The purpose of this study was to test the equivalence of efficacy and compare the safety of the 6% hydroxyethyl starches (HES) Voluven® (HES 130/0.4; Fresenius Kabi, Bad Homburg, Germany) and hetastarch (HES 670/0.75 in saline) for intravascular volume replacement therapy during major orthopedic surgery. Methods:In a prospective, controlled, randomized, double-blind, multicenter trial of patients undergoing major orthopedic surgery, 49 patients were treated with HES 130/0.4 and 51 patients were treated with hetastarch. Infusion of colloids was guided by central venous and arterial blood pressures. The primary efficacy endpoint was the volume of colloid solution infused; the primary safety endpoints were calculated total erythrocyte loss, the nadir factor VIII activity, and the nadir von Willebrand factor concentration within 2 h of completion of surgery. Results:The total volume of colloid solution required for intraoperative volume replacement did not differ between HES 130/0.4 and hetastarch (1,613 ± 778 [SD] ml for HES 130/0.4 and 1,584 ± 958 ml for hetastarch). The nadir factor VIII activity within 2 h of the end of surgery was lower for hetastarch than for HES 130/0.4 (P = 0.0499); for those who received greater than 1,000 ml colloid, the nadir factor VIII activity and von Willebrand factor concentration within 2 h of end of surgery were lower for hetastarch than for HES 130/0.4 (P = 0.0487 and P = 0.008, respectively). Conclusion:Voluven® (HES 130/0.4) and hetastarch are equally efficacious plasma volume substitutes; however, HES 130/0.4 has a lesser effect on coagulation.

Ketamine attenuates post-operative cognitive dysfunction after cardiac surgery

Background: Post‐operative cognitive dysfunction (POCD) commonly occurs after cardiac surgery. Ketamine exerts neuroprotective effects after cerebral ischemia by anti‐excitotoxic and anti‐inflammatory mechanisms. We hypothesized that ketamine attenuates POCD in patients undergoing cardiac surgery concomitant with an anti‐inflammatory effect.

Treatment of Acute Postoperative Hypertension in Cardiac Surgery Patients: An Efficacy Study of Clevidipine Assessing Its Postoperative Antihypertensive Effect in Cardiac Surgery-2 (ESCAPE-2), a Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUND: Acute postoperative hypertension is a well-known complication of cardiac surgery and is associated with postoperative morbidity. Clevidipine, an ultrashort-acting, third-generation dihydropyridine calcium channel blocker, exerts vascular-selective, arterial-specific vasodilation to decrease arterial blood pressure without negatively impacting cardiac function. In this double-blind, placebo-controlled trial, we examined the efficacy and safety of clevidipine in treating postoperative hypertension in cardiac surgery patients. METHODS: Two hundred six patients undergoing cardiac surgery were randomized preoperatively. Of these, 110 met postrandomization inclusion criteria for the study [systolic blood pressure (SBP) ≥140 mm Hg within 4 h of admission to a postoperative setting, and clinically assessed as needing SBP reduction by ≥15% from baseline]. Patients received an infusion of either clevidipine (0.4–8.0 &mgr;g kg−1 min−1) or 20% lipid emulsion (placebo) for 30 min to a maximum of 1 h unless treatment failure occurred sooner. The primary end point was the incidence of treatment failure, defined as the inability to decrease SBP by ≥15% from baseline, or the discontinuation of study treatment for any reason within the 30-min period after study drug initiation. RESULTS: Clevidipine-treated patients had a significantly lower incidence of treatment failure than placebo patients [8.2% (5 of 61) vs 79.6% (39 of 49), P < 0.0001]. Treatment success was achieved in 91.8% of clevidipine-treated patients. Median time to target SBP with clevidipine was 5.3 min (95% confidence interval, 4–7 min). No clinically significant increase in heart rate from baseline was observed. Adverse event rates were similar for both treatment groups. CONCLUSIONS: Clevidipine is effective and safe in the rapid treatment of acute postoperative hypertension after cardiac surgery.

Postoperative cognitive dysfunction in older patients with a history of alcohol abuse.

Background: Postoperative cognitive dysfunction (POCD) affects a significant number of patients and may have serious consequences for quality of life. Although POCD is most frequent after cardiac surgery, the prevalence of POCD after noncardiac surgery in older patients is also significant. The risk factors for POCD after noncardiac surgery include advanced age and preexisting cognitive impairment. Self-reported alcohol abuse is a risk factor for postoperative delirium, but its significance for long-term POCD has not been investigated. The goal of this study was to determine whether neurocognitive function is impaired after noncardiac surgery during general anesthesia in older patients with a history of alcohol abuse. Methods: Subjects aged 55 yr and older with self-reported alcohol abuse (n = 28) and age-, sex-, education-matched nonalcoholic controls (n = 28) were tested using a neurocognitive battery before and 2 weeks after elective surgery (n = 28) or a corresponding time interval without surgery (n = 28). Verbal memory, visuospatial memory, and executive functions were assessed. A neurologic examination was performed to exclude subjects with potential cerebrovascular damage. Results: Significant three-way interactions (analysis of variance) for Visual Immediate Recall, Visual Delayed Recall, Semantic Fluency, Phonemic Fluency, and the Color-Word Stroop Test implied that cognitive performance in the alcoholic group decreased after surgery more than it did in the other three groups. Conclusions: The results suggest that a history of alcohol abuse in older patients presents a risk for postoperative cognitive impairment in the domains of visuospatial abilities and executive functions that may have important implications for quality of life and health risks.

Postoperative Delirium and Short-term Cognitive Dysfunction Occur More Frequently in Patients Undergoing Valve Surgery With or Without Coronary Artery Bypass Graft Surgery Compared With Coronary Artery Bypass Graft Surgery Alone: Results of a Pilot Study

OBJECTIVE The authors tested the hypothesis that patients undergoing valve repair or replacement surgery with or without coronary artery bypass graft (CABG) surgery using cardiopulmonary bypass (CPB) had a greater incidence of postoperative delirium and cognitive dysfunction compared with patients undergoing CABG surgery alone. DESIGN Prospective study. SETTING Veterans Affairs medical center. PARTICIPANTS Forty-four age- and education-balanced male patients (≥ 55 years of age) undergoing elective cardiac surgery with CPB (n = 22 valve ± CABG surgery and n = 22 CABG surgery alone) and nonsurgical controls (n = 22) were recruited. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Delirium was assessed with the Intensive Care Delirium Screening Checklist before and for 5 consecutive days after surgery. Recent verbal and nonverbal memory and executive functions were assessed using a psychometric test battery before and 1 week after cardiac surgery or at 1-week intervals in nonsurgical controls. Intensive care unit stay, hospital stay, and 30-day readmission were significantly (p = 0.03, p = 0.01, and p = 0.04, respectively) longer in patients undergoing valve surgery ± CABG surgery versus CABG surgery alone. Postoperative delirium occurred more frequently (p = 0.01) in patients undergoing valve ± CABG surgery versus CABG surgery alone. Overall cognitive performance (composite z score) after surgery also was impaired significantly (p = 0.004) in patients undergoing valve ± CABG surgery compared with CABG surgery alone. The composite z score after surgery decreased by at least 1.5 standard deviations in 11 patients (50%) versus 1 patient (5%) without valve surgery compared with nonsurgical controls (p = 0.001, Fishers exact test). The presence of delirium predicted a composite z score decrease of 1.2 points (odds ratio = 0.30; 95% confidence interval, 0.13-0.68). CONCLUSIONS The results indicated that patients undergoing valve surgery with or without CABG surgery have a higher incidence of postoperative delirium and cognitive dysfunction 1 week after surgery compared with those undergoing CABG surgery alone.

Metabolic Syndrome Exacerbates Short-term Postoperative Cognitive Dysfunction in Patients Undergoing Cardiac Surgery: Results of a Pilot Study

OBJECTIVE The authors tested the hypothesis that patients with metabolic syndrome are more likely to develop short-term cognitive dysfunction after cardiac surgery with cardiopulmonary bypass. DESIGN A prospective study. SETTING Veterans Affairs medical center. PARTICIPANTS Fifty-six age- and education-balanced patients undergoing elective cardiac surgery with cardiopulmonary bypass (28 patients with and without metabolic syndrome in two separate groups) and 28 nonsurgical controls were enrolled. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Recent verbal and nonverbal memory and executive functions were assessed using a psychometric test battery before and 1 week after cardiac surgery or at 1-week intervals in nonsurgical controls. Neurocognitive scores under the baseline condition were at least 1 z score (1 standard deviation) worse in surgical patients with compared without metabolic syndrome in all 3 cognitive areas (nonverbal and verbal recent memory and executive functions). Neurocognitive performance further deteriorated after surgery by at least 1 z score on 3 tests in the verbal memory modality (Immediate and Delayed Story Recall and Delayed Word List Recall). Overall cognitive performance (composite z score) after surgery was significantly (p = 0.03) worse in metabolic syndrome patients compared with those who did not have the disorder. CONCLUSIONS The results indicate that short-term cognitive functions were more profoundly impaired in patients with metabolic syndrome undergoing cardiac surgery with cardiopulmonary bypass compared with their healthier counterparts.

Massive retrograde acute type B aortic dissection in a postpartum woman with a family history of Marfan syndrome.

Acute aortic dissection is rare but potentially catastrophic complication of pregnancy. Aortic root enlargement, congenital bicuspid aortic valve disease, and Marfan syndrome have been identified as critical risk factors for peripartum aortic dissection. Most of the aortic dissections reported to date involve the ascending aorta and occur before delivery, but only a few cases of postpartum aortic dissection have been described. In this report, we discuss the management of a multigravid parturient with an extensive family history of Marfan syndrome who developed a massive retrograde type B aortic dissection 7 days after a normal spontaneous vaginal delivery.

Remote Ischemic Preconditioning Prevents Deterioration of Short-Term Postoperative Cognitive Function After Cardiac Surgery Using Cardiopulmonary Bypass: Results of a Pilot Investigation

OBJECTIVE Remote ischemic preconditioning (RIPC) exerts neuroprotective effects in models of cerebral ischemia-reperfusion injury. The authors tested the hypothesis that RIPC decreases the incidence of postoperative delirium and prevents deterioration of short-term postoperative cognitive function in isoflurane-fentanyl-anesthetized patients undergoing cardiac surgery using cardiopulmonary bypass (CPB). DESIGN Randomized, blinded, single-center pilot investigation. SETTING Veterans Affairs Medical Center. PARTICIPANTS Thirty age- and education-matched men≥55 years of age undergoing elective coronary artery or valve surgery using CPB. Fifteen nonsurgical patients also were enrolled. INTERVENTIONS RIPC was produced after induction of anesthesia using 4 cycles of brief (5 minutes) upper extremity ischemia (tourniquet inflation to 200 mmHg) interspersed with 5-minute periods of reperfusion (tourniquet deflation). MEASUREMENTS AND MAIN RESULTS The Intensive Care Delirium Screening Checklist was used to assess delirium before and each day after surgery for as many as 5 consecutive days. Recent verbal and nonverbal memory and executive functions were assessed before and 1 week after surgery using a standard neuropsychometric test battery or at 1-week intervals in nonsurgical controls. The Geriatric Depression and the Hachinski Ischemia scales were used to identify the presence of clinical depression and vascular dementia, respectively. No differences in delirium scores were observed between RIPC and control groups (p=0.54). Baseline neurocognitive scores were similar in patients with versus without RIPC in all 3 cognitive domains. Significant declines in performance on 2 nonverbal memory tests (figure reconstruction and delayed figure reproduction; p=0.001 and p=0.003, respectively) and 1 verbal memory test (delayed story recall; p=0.0004) were observed 1 week after surgery in patients who were not treated with RIPC. There were no changes in performance of measures of executive function in this group. In contrast, performance on all cognitive tests was unchanged after compared with before surgery in patients receiving RIPC. At least a 1-standard deviation decline from baseline in cognitive performance was detected in figure reconstruction, delayed figure reproduction, immediate story recall, and delayed story recall in patients who were not exposed to RIPC. The incidence of at least a 1-standard deviation decline in neuropsychometric tests was observed in significantly fewer (1 v 9; p<0.0001) patients with versus without RIPC treatment based on composite Z-scores. Overall cognitive performance after surgery was better in patients treated with versus without RIPC (p=0.002). Clinical depression and vascular dementia were not detected in either group. CONCLUSION The results of this pilot investigation indicated that RIPC prevented deterioration of short-term postoperative cognitive function but were unable to detect any difference in delirium in isoflurane-fentanyl-anesthetized patients undergoing cardiac surgery using CPB.

History of Post-traumatic Stress Disorder Is Associated With Impaired Neuropsychometric Performance After Coronary Artery Surgery

OBJECTIVE To determine if preoperative history of post-traumatic stress disorder (PTSD) is associated with postoperative cognitive impairment. DESIGN An observational study. SETTING Veterans Affairs Medical Center. PARTICIPANTS Cardiac surgical patients. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS Age- and education-balanced patients (≥55 years of age) undergoing cardiac surgery (n = 30 with a history of PTSD+, n = 56 without a history of PTSD-) and nonsurgical controls (n = 28) were recruited. Recent verbal and nonverbal memory and executive functions were assessed before and 1 week after cardiac surgery or at 1-week intervals in nonsurgical controls. Demographic and medical parameters were similar between groups with the exception of preoperative depression and a history of alcohol dependence. Preoperative depression scores were significantly (p = 0.02) higher in PTSD+ compared with PTSD- groups. Immediate Word List Recall and Delayed Word List Recall under baseline conditions were worse in PTSD+ compared with PTSD- patients. Cognitive performance after surgery decreased by at least 1 standard deviation in 27 PTSD- patients (48%) and in 25 PTSD+ patients (83%) (p = 0.002) versus nonsurgical controls. Multivariate regression analysis (including a history of depression and alcohol dependence) revealed that a history of PTSD was significantly associated with overall (including nonverbal recent memory, verbal recent memory, and executive functions) postoperative cognitive dysfunction (p = 0.005). CONCLUSIONS The current findings suggest that patients with a history of PTSD undergoing coronary artery surgery using cardiopulmonary bypass may be especially vulnerable to postoperative cognitive impairment.