Materials and methods: This cohort study included 280 patients (male = 226, female = 54) scheduled for primary anterior cruciate ligament (ACL) reconstruction. Interrelationships between quadruple semitendinosus (ST) graft and anthropometric parameters (age, sex, height, weight, and BMI) were assessed using Pearson Correlation test and regression analysis. Difference among gender was analysed using Mann Whitney and t test. The observed graft diameter was also compared with the literature using Bland - Altman plot.
Results: Mean age of cohort was 29 years (range, 17-50 years), mean height was 1.69m (range, 1.6-1.9m), mean weight was 75 kg (range, 50-116kg) and mean BMI was 26kg/m2 (range 16.65-40.40kg/m2). Mean quadruple length of harvested ST graft was 7cm (7.1±0.6 cm, range, 5.6-8.8cm) and mean diameter was 8mm (8.2±0.8mm, range, 6.5-10mm). Only height and weight were significantly correlated with graft length and diameter in both sex (p value <0.05). Female, compared to male, had significantly smaller (p<0.0001) and thinner graft (p<0.0001). There was a strong agreement between the literature and our observed graft diameter, but with an overestimated graft diameter in 18.5% of the cases.
Conclusion: Among anthropometric parameter, only height and weight had moderate positive correlation with graft diameter. Males had longer and wider ST graft in contrast to age-matched female group.
RESULTS: No significant difference in plasma propranolol (mean +/- SEM) levels was seen between races six hours after the last dose (Malays, 59.7 +/- 8.8 ng/ml, Indians, 67.6 +/- 19.3 ng/ml, Chinese, 58.4 +/- 7.9 ng/ml). Chinese were least sensitive to the bradycardic and hypotensive effects of propranolol at rest and exercise. Indians and Malays had significant reduction of supine systolic blood pressure with propranolol but not Chinese. Comparison of percentage reductions of systolic blood pressure at supine, sitting and exercise by repeated measure analysis showed the Malays to have significantly higher change compared to the Chinese (p = 0.022). Similarly, comparison of percentage reductions of heart rate at supine, sitting and exercise by repeated measure analysis showed the Malays to have significantly higher change compared to the Chinese (p = 0.040). Average change in potassium concentrations at peak exercise and recovery showed the Indians to have significantly higher increase in potassium levels with propranolol compared to the Malays (p = 0.038). However, no significant interethnic difference was seen in the reduction of glucose levels at rest, peak exercise or recovery. Also, no significant interethnic difference was seen in reduction of FEV1 values.
CONCLUSION: We, therefore, conclude that ethnic differences in response to blockade of beta-receptors exist among racial groups in Malaysia. These differences were seen at similar plasma drug levels between races suggesting ethnic differences in drug sensitivity, rather than differences in drug disposition.