Biomedical subjects

Frederick E Sieber

Publications and source records attributed to Frederick E Sieber.

5 recordsLinked to original sources

PubMed2006

Hippocampus bcl-2 and bax expression and neuronal apoptosis after moderate hypothermic cardiopulmonary bypass in rats.

Using a rat model of moderate hypothermic (26 degrees C-28 degrees C) cardiopulmonary bypass (CPB) with hemodilution, we investigated hippocampal apoptotic gene expression and neuronal apoptosis up to 6 h after CPB. The CPB was performed on male rats (380-400 g) under general anesthesia with isoflurane and fentanyl. The right atrium and tail artery were cannulated, and a peristaltic pump and membrane oxygenator were used for CPB. Two groups were studied: Group 1 consisted of fasted rats (n = 15) subjected to 60 min of moderate hypothermic nonpulsatile CPB; Group 2 consisted of sham-operated rats (n = 15). At 1 h after CPB, in 6 rats per group, hippocampus was processed for the apoptotic gene (bcl-2 and bax) messenger RNAs detection by reverse transcriptase polymerase chain reaction, and messenger RNA expression was determined by the ratio of the polymerase chain reaction product of bcl-2 or bax to the beta-actin gene. At 6 h after CPB, in 6 rats per group, hippocampus expression of Bcl-2 and bax protein was determined by immunohistochemistry, and neuronal apoptosis was detected by TUNEL. At 6 h after CPB, in three rats per group, changes in hippocampal CA1 neuronal ultra structure were determined with electron microscopy. Group 1 had increased ratios of bcl-2/beta-actin, bax/beta-actin, and bax/bcl-2 mRNA at 1 h after CPB (bcl-2/beta-actin, 0.82 +/- 0.14 versus 0.63 +/- 0.07; P = 0.03; bax/beta-actin, 1.04 +/- 0.14 versus 0.56 +/- 0.03; P = 0.00; bax/bcl-2, 1.31 +/- 0.12 versus 0.84 +/- 0.09; P = 0.02; Group 1 versus Group 2, respectively). Group 1 had increased bcl-2 and bax protein expression in hippocampal CA1 region at 6 h after CPB (bcl-2, 0.18 +/- 0.05 versus 0.09 +/- 0.01; P = 0.02; bax, 0.20 +/- 0.06 versus 0.04 +/- 0.02; P = 0.01; Group 1 versus Group 2, respectively). Group 1 had increased TUNEL staining in hippocampus CA1 at 6 h after CPB (0.14 +/- 0.02 versus 0.03 +/- 0.01; P = 0.00; Group 1 versus Group 2, respectively). In Group 1 CA1 hippocampus neurons, ultra-structural changes consistent with apoptosis occurred. In rats, moderate hypothermic CPB with hemodilution is associated with CA1 hippocampus bax and bcl-2 gene expression and neuronal apoptosis during the early post-CPB recovery period.

Animals↗

PubMed2005

Recovery room delirium predicts postoperative delirium after hip-fracture repair.

UNLABELLED: In this study, we sought to determine the incidence of recovery room delirium in elderly patients having hip-fracture repair under general anesthesia and to discover whether recovery room delirium is associated with continuing postoperative delirium. In this prospective study, patients undergoing hip-fracture repair were anesthetized using a standardized protocol. In addition, postoperative pain management was standardized in both the postoperative anesthesia care unit and in the hospital ward. The presence of delirium was determined using the confusion assessment method (CAM) score. Recovery room delirium was assessed by obtaining a CAM score at 60 min after discontinuation of isoflurane. Postoperative delirium was assessed by obtaining a daily CAM score during the postoperative in-hospital recovery period. Fifty patients consented to the study and 47 patients were included in the analysis (surgery cancelled postinduction n = 1; nonadherence to protocol n = 2). Average patient age was 77 +/- 1 (mean +/- SE) yr (range, 56-98 yr). Seventy-seven percent of the study patients were ASA class III or more. The prevalence of recovery room delirium was 45%. The prevalence of postoperative delirium was 36%. Recovery room delirium predicted postoperative delirium (P < 0.001, Fisher's exact test) with a sensitivity of 100% and a specificity of 85%. Analgesic doses administered in the postoperative anesthesia care unit and ward were similar in patients with or without postoperative delirium. Results of this study show that recovery room delirium is a strong predictor of postoperative delirium. IMPLICATIONS: In patients undergoing hip-fracture repair, recovery room delirium is a strong predictor of postoperative delirium when using a standardized protocol for general anesthesia and postoperative pain management.

Aged↗

PubMed2004

Age associated issues: geriatrics.

The effects of aging on the body are numerous, but the most important point with regard to surgery is to differentiate the effects of aging from those of the pathology associated with a disease process that may also be present in the elderly patient. Studies tend to validate the premise that there are no labs mandated solely because of a patient's age. Rather, the physician should analyze the geriatric patient with reference to the nature of the surgery emergent versus elective; the degree of risk for the surgical procedure itself-that is high-risk, intermediate--risk, or low-risk surgery; while bearing in mind the patient's overall physiologic state. In assessing a patient's overall physiologic state an organ systems based approach focusing on the cardiac, respiratory, renal, hepatic, endocrine, nutritional, and neurologic systems may be warranted and beneficial. In the elderly population one of the key predictors of perioperative complications seems to be the geriatric patient's preoperative condition and preoperative level of functioning.

Age Factors↗

PubMed2004

Brief postoperative delirium in hip fracture patients affects functional outcome at three months.

UNLABELLED: It is unclear how brief postoperative delirium (DEL) affects functional outcomes. In this study, we sought to determine if patients with brief postoperative DEL (<6-wk duration) have different living situations when compared with non-DEL patients after hip fracture repair. In a prospective study, patients admitted to the geriatric hip fracture service were assessed every postoperative day for the presence of DEL using the confusion assessment method (CAM) score. Patients were reassessed at 6 wk and 3 mo postoperatively for CAM score, current living situation, and activities of daily living. Group comparisons were tested after dividing patients into two groups: DEL (DEL; [+] CAM at any time during the postoperative period while in the hospital); no-DEL (no DEL; [-] CAM throughout the postoperative period while in the hospital). The study included 92 patients of whom 26 (28%) were CAM (+) after surgery. At 6 wk follow-up, n = 81; at 3 mo follow-up, n = 76. Eight patients died during the study. At 6 wk and 3 mo, a larger percentage of DEL patients were not living with a family member (27% versus 8% patients not living with a family member at 3 mo follow-up in DEL and no-DEL, respectively). There was no difference in activities of daily living by 3 mo. We conclude that brief postoperative DEL lasting <6 wk is a determining factor for poor long-term functional outcome after hip fracture repair, because it significantly impacts the ability to live independently. IMPLICATIONS: Brief postoperative delirium lasting <6 wk is a determining factor for poor long-term functional outcome after hip fracture repair, because it significantly impacts the ability to live independently.

Activities of Daily Living↗

PubMed2002

Preoperative factors associated with postoperative change in confusion assessment method score in hip fracture patients.

UNLABELLED: Postoperative delirium is a major problem in elderly patients undergoing surgical repair of hip fracture. It is imperative to identify potentially treatable preoperative factors associated with the onset of postoperative delirium to optimize outcome. We sought to determine what preoperative variables are associated with postoperative delirium in geriatric patients undergoing surgical repair of hip fracture. In a prospective, IRB-approved study, patients admitted to the geriatric hip fracture service were examined daily in the hospital for the occurrence of postoperative delirium. All patients with a preoperative diagnosis of dementia or delirium were eliminated. A positive confusion assessment method score ([+]CAM) was used to determine the presence of postoperative delirium during the acute hospital stay. To determine the association between preoperative variables (demographics, laboratory values, and comorbidities) and postoperative (+)CAM scores, chi(2) and logistic regression analysis were performed with calculation for the odds ratios (OR). One-hundred-sixty-eight patients (72% women) were included in the analysis. Twenty-eight percent (n = 47) of patients had a (+)CAM score. Three variables were significant predictors of a (+)CAM score: (a) normal white blood cell count (OR, 2.2), (b) abnormal serum sodium (OR, 2.4); and (c) ASA physical status >II (OR, 11.3). The results suggest that preoperative medical conditions (abnormal serum sodium and ASA physical status >II) and an inability to mount a stress response (normal white blood cell count) may influence the patient's postoperative mental status. In particular, two of the risk factors we identified may be amenable to therapy and are abnormal serum sodium and lack of an increase in white blood cell count during the stress of trauma and surgery. IMPLICATIONS: This prospective study investigated preoperative variables that are predictive of postoperative delirium in geriatric patients undergoing surgical repair of hip fracture. The results suggest that the patient's preoperative medical condition and inability to mount a stress response influence postoperative delirium.

Age Factors↗