Significant Differences In Prothrombin Time Research Articles

Vitamin E and a-Lipoic Acid Supplementation Increase Bleeding Tendency via an Intrinsic Coagulation Pathway

Vitamin E and alpha-lipoic acid are potent nutritional antioxidants, and when used together, their antioxidant capabilities are improved as alpha-lipoic acid recycles vitamin E. Supplementation of vitamin E has been shown to prolong platelet aggregation but the effects of vitamin E and alpha-lipoic acid supplementation on bleeding tendency have yet to be reported. Young, male rats consumed either control diet (n=5) or vitamin E and alpha-lipoic acid-supplemented diet (n=5) for 14 weeks. Activated partial thromboplastin time (APTT) and prothrombin time (PT) were measured as markers of intrinsic and extrinsic coagulation pathways respectively in addition to lipid peroxidation (malondialdehyde). Supplementation significantly prolonged APTT (23.8+/-1.5 vs 31.4+/-1.2s, p<0.05) compared to the control diet; however, there was no significant difference in PT (27.8+/-1.5 vs 26.6+/-0.9s, p>0.05). While vitamin E was increased (p<0.05), there was no significant difference in plasma levels of malondialdehyde (p>0.05). Dietary supplementation of vitamin E and alpha-lipoic acid increases bleeding tendency via inhibition of the intrinsic coagulation pathway with no change in markers of lipid peroxidation. Such supplementation could benefit patients with cardiovascular disease who exhibit elevated levels of coagulation and oxidative stress.

Ibuprofen for tonsillectomy pain in children: Efficacy and complications

We designed a prospective, randomized, double-blind study to test the efficacy and safety of ibuprofen compared with acetaminophen with codeine for pediatric posttonsillectomy/adenotonsillectomy patients. Twenty-seven children, aged 6 to 16 years, were enrolled. We collected information on pain control, return to normal sleep pattern, return to normal diet, and duration for which medication was required. Coagulation profiles were measured before surgery and on postoperative day 3. Acetaminophen with codeine was more effective in controlling pain on days 1 and 3 ( p = 0.0475 and 0.0328, respectively). However, we detected no difference between the treatment groups ( p = 0.2216) with regard to pain control on day 5. The ibuprofen group required medication for a longer period ( p = 0.0464). We detected no statistically significant differences between groups with regard to return to normal diet ( p = 0.2346) and return to normal sleep pattern ( p = 0.9554). The postoperative hemorrhage rate was 0% in the acetaminophen-with-codeine group and 12.5% in the ibuprofen group. The ibuprofen group demonstrated a mean increase in bleeding time of 2.07 minutes on the third postoperative day ( p = 0.0379). The mean change in postoperative bleeding time between the two groups was statistically significant ( p = 0.0140). We found no statistically significant differences in prothrombin time and partial thromboplastin time between groups. On the basis of the findings of this pilot study, we conclude that acetaminophen with codeine is safer and more efficacious than ibuprofen in the management of posttonsillectomy/adenotonsillectomy pain in children. (Otolaryngol Head Neck Surg 1998;119:492-6.)

Ethnic variations in the haemostatic system

A wide variety of haemostatic variables were measured in healthy male subjects predominantly blood donors residing in Riyadh, the capital city of Saudi Arabia. Subjects were divided according to ethnic origin: Saudi Arabs n = 487, Westerners (Europeans and Americans) n = 300, South East Asians (Koreans and Filipinos) n = 360, and West Africans n = 82. There were no significant differences in prothrombin time, partial thromboplastin time, thrombin time, reptilase time, plasma fibrinogen, antithrombin, plasminogen and platelet count between Saudis, Westerners and Asians. Africans exhibited significantly lower plasma levels of fibrinogen, platelet count and plasminogen than other ethnic groups. Arabs and Africans had higher levels of FVIII:C and vWF:ristocetin cofactor than Westerners. On the other hand, FX was significantly higher in Westerners than in other ethnic groups. Smokers had higher fibrinogen levels than non-smokers. These variations, which could not be related to blood group distribution, physical parameters of height and weight, may be due to genetic and/or dietary habits. In conclusion, this study established the existence of racially determined variations in haemostatic variables, with Black Africans showing changes consistent with a lesser tendency towards atherosclerosis and cardiovascular disease than other ethnic groups. These variations should be taken into account when investigating the haemostatic system in patients.

Thrombocytopenia following peritonitis in surgical patients. A prospective study.

Thrombocytopenia is commonly found in patients with serious infection. To investigate this phenomenon, 14 consecutive patients (68 +/- 10 years) who underwent laparotomy for bowel perforation and culture-proven peritonitis were prospectively studied. Ten noninfected laparotomy patients served as a control group. None of the 10 control patients developed thrombocytopenia. Of the infected group, 12 of 14 patients (85%) developed thrombocytopenia (less than 100,000/mm3). One patient (9%) developed disseminated intravascular coagulation (DIC). Of the remaining 11 patients with thrombocytopenia, platelet counts fell from preoperative level of 350,000 +/- 166,000 to 54,000 +/- 30,000 (p less than 0.001) and reached this nadir 4.3 +/- 2 days after surgery. There was no statistically significant difference in prothrombin time, partial thromboplastin time, or fibrinogen levels before versus after operation in this group. Bleeding times in seven patients were 5.5 +/- 2 minutes, and bone marrow examination in five patients with platelet counts of less than 50,000/mm3 revealed normal or increased megakaryocytes. No patient in this group bled, had medications held, or received platelet transfusions. Platelet counts increased greater than 100,000/mm3 at a mean of 8.9 +/- 4.1 days after operation. It is concluded that thrombocytopenia is common following surgery for intra-abdominal infection, is not usually associated with DIC, clinical bleeding, or coagulation abnormalities, does not commonly result from bone marrow suppression, and is transient and does not require routine platelet transfusions.