Validation of esophageal Doppler for noninvasive hemodynamic monitoring under pneumoperitoneum.

BACKGROUND: Commonly used perioperative measurements of hemodynamics, such as Swan-Ganz catheter assessment, are invasive and may not be reliable under pneumoperitoneum. The purpose of this study was to validate the use of esophageal Doppler for noninvasive hemodynamic monitoring under pneumoperitoneum in an experimental pig model. METHODS: Eight female pigs were submitted to two 30-min study periods, one each for the baseline (no interventions) and pneumoperitoneum (12-mmHg carbon dioxide pneumoperitoneum) conditions. One pig was excluded because of tachycardia (>140 at baseline). A Swan-Ganz pulmonary artery catheter was used to measure cardiac output (CO-SG) and pulmonary capillary wedge pressure (PCWP). An esophageal Doppler probe was inserted to record cardiac output (CO-ED) and corrected flow time (FTc), an index of preload. Transthoracic echocardiography was used to measure left ventricular end-diastolic diameter (LVEDD) and cardiac output (CO-TTE). Pearson correlation was used to assess individual associations between the measured hemodynamic parameters. RESULTS: There was good correlation between CO-ED and CO-SG (r = 0.577; p < 0.001) and excellent correlation between CO-ED and CO-TTE (r = 0.815; p < 0.001). There was no correlation between FTc and LVEDD or PCWP. These relationships were consistent when analyzed separately at baseline and during pneumoperitoneum. CONCLUSION: Esophageal Doppler monitoring is a valid noninvasive method of estimating cardiac output at baseline and during pneumoperitoneum in a porcine model. Corrected flow time did not correlate with other estimates of preload at baseline or during pneumoperitoneum.

Advances in molecular genetics and the prevention and treatment of substance misuse: Implications of association studies of the A1 allele of the D2 dopamine receptor gene.

Substance misuse is influenced by multiple genetic and environmental factors. Recent research has identified a number of potential genetic markers of risk and those associated with drug reward substrates show particular promise. The current study reexamines the extant published data of the association between the D2 dopamine receptor (DRD2) gene minor Taq 1A (A1) allele and substance misuse risk. A series of meta-analyses was performed on 64 studies examining DRD2 A1+ allelic status and substance misuse. In addition, personality was examined as a possible endophenotype. Significant association was found between the A1 allele and severe substance dependence in both Caucasian and non-Caucasian groups. The data did not support a significant association between the A1 allele and personality features. While the specific mechanism underlying these associations requires further elucidation, this genetic marker shows promise as a marker of brain reinforcement processes. Possible ways of utilising the A1 allele to inform prevention and treatment initiatives are discussed.

An exercise program in the treatment of fibromyalgia.

OBJECTIVE: To assess the utility of an exercise program, which included aerobic, flexibility and strengthening elements, in the treatment of fibromyalgia (FM). FM is a chronic musculoskeletal condition characterized by diffuse musculoskeletal pain and aching. It has been suggested that aerobic exercise is helpful in its treatment. METHODS: We studied 60 patients who met American College of Rheumatology criteria for FM and had no significant comorbidities. Measurements performed on each patient at the pre and poststudy assessment included the number of tender points (TP), total myalgic scores (TM), aerobic fitness (AF), flexibility and isokinetic strength. After initial evaluation patients were randomly assigned to either an exercise or a relaxation group. Each group met 3 times per week for 6 weeks for 1 h of supervised exercise or relaxation. All patients data were stored in a computerized database and statistical analysis was performed on all pre and poststudy assessments. RESULTS: Thirty-eight patients (18 exercise and 20 relaxation) completed the study. Analysis of our data showed no significant difference between the groups in their prestudy assessment. Poststudy assessments, however, showed a significant improvement between the exercise and relaxation groups in TP (p < 0.05), TM (p < 0.05), and AF (p < 0.05). Similar improvements were also found when the pre and poststudy assessment of the exercise group were compared. CONCLUSION: Exercise is helpful in the management of FM in the short term. It also shows that FM patients can undertake an exercise program which includes aerobic, flexibility, and strength training exercises without adverse effects. The long term utility of this type of exercise requires further evaluation.