Genetic control of platelet activation in inbred mouse strains

Platelet activation in inbred mouse strains was studied using expression of P-selectin as a marker of activated platelets. P-selectin expression in response to no added stimulus (spontaneous activation) or in response to adenosine diphosphate (ADP) and epinephrine or thrombin, was assessed using a flow cytometric assay. Wide variation in the responsiveness of different strains was observed with strains SJL and AKR in particular showing very high levels of spontaneous activation. Genetic studies suggest that this phenomenon is under control of a small number of genes and that the same loci are probably responsible for the high activation of both SJL and AKR. Bone marrow transplant experiments show that the trait is expressed in the platelet itself. Screening of SWXJ and AKXD recombinant inbred lines suggests that one of the responsible genes is located on chromosome 3.

Probable alcohol abuse or dependence: a risk factor for intensive-care readmission in patients undergoing elective vascular and thoracic surgical procedures. Mayo Perioperative Outcomes Group

OBJECTIVE

To determine whether alcohol abuse or dependence is a risk factor for perioperative complications, increased duration of hospital stay, and increased utilization of nursing resources in patients undergoing thoracic and vascular surgical procedures.

MATERIAL AND METHODS

We conducted a prospective study of all adult patients who underwent an elective vascular or thoracic surgical procedure and who received postoperative care in an intensive-care setting. Patients were screened for alcohol abuse or dependence, and actual versus expected durations of stay were evaluated. The patients' medical records were reviewed for preoperative comorbidities and perioperative complications. Fisher's exact test and the rank sum test were used in the analyses.

RESULTS

Of 321 study subjects, 290 were classified as nonalcoholic and 31 as probable alcoholic patients. Patients in the probable alcohol abuse group had a significantly increased rate of alcohol withdrawal (12.9% versus 1.7%; P = 0.006) in comparison with patients in the nonalcoholic group. Patients in the probable alcohol abuse group were readmitted to an intensive-care unit more frequently (19.4% versus 7.9%; P = 0.047) and required sedation more often (32.3% versus 13.5%; P = 0.014) than those in the nonalcoholic group. No significant differences were found between the two study groups in intensive-care unit and hospital durations of stay or in utilization of nursing resources. A dismissal diagnosis of alcoholism was recorded for only one of four patients who had a documented withdrawal episode among those categorized in the probable alcoholic group and for three of five patients with alcohol withdrawal symptoms categorized in the nonalcoholic group.

CONCLUSION

Except for the occurrence of alcohol withdrawal syndrome, study patients classified in the probable alcohol abuse group did not have more medical or surgical perioperative complications than patients in the nonalcoholic group. They did have significantly more intensive-care setting readmissions. Patients with documented alcohol withdrawal episodes frequently were dismissed without a diagnosis of substance abuse or dependence.