Type A Cubital Venous Pattern among Students of a Dental College: A Descriptive Cross-sectional Study

ABSTRACT Introduction: Superficial veins in cubital fossa vary frequently in their anatomical pattern. The knowledge of variation of the cubital venous pattern is very essential for medical professionals for venous access during different medical procedures. This study aims to find the prevalence of Type A cubital venous pattern among students of a dental college. Methods: This descriptive cross-sectional study was conducted among 133 dental students of age 18 to 25 years in the department of anatomy of a dental college from November 2020 to February 2021. This study was conducted after obtaining ethical clearance from the Institutional Review Committee. Convenience sampling used and data was analyzed using Statistical Package for Social Sciences version 20. Point estimate at 95% Confidence Interval was calculated along with frequency and proportion for binary data. Results: Out of 133 dental students, Type A cubital venous pattern was found in 192 arms (72.18%) (64.56-79.79 at 95% Confidence Interval). Type A cubital venous pattern was seen in 116 (43.61%) left arms and 76 (28.57%) right arms of students. This pattern was observed in 139 (52.26%) females and 53 (19.92%) male arms respectively. Conclusions: This study showed higher Type A cubital venous pattern among dental students than other international studies.


INTRODUCTION
The cubital fossa is a depression on the anterior aspect of the elbow. Main superficial veins in cubital fossa are cephalic, basilic and median veins. The cephalic vein takes its origin from the lateral aspect of the dorsal venous network of the hand and ends in the axillary vein. The basilic vein starts from the medial end of the dorsal venous network and forms an axillary vein. The medial cubital vein connects cephalic vein to basilic vein. 1 These veins are commonly used for blood sampling, transfusions, and intravenous injections under emergency conditions. These veins are subjected to variation in their anatomic pattern. According to Del Sol, et al. cubital venous pattern is classified as Type A to Type F. 2 This study aims to find the prevalence of Type A pattern of superficial veins in cubital fossa among dental students. Knowledge of the anatomic variation of these veins will be helpful for health professionals for easy access.

METHODS
This was a descriptive cross-sectional study conducted on 133 students of 18-25 years from November 2020 to February 2021 in the Department of Anatomy, Kantipur Dental College Basundhara, Kathmandu. Ethical approval (reference number-36/020) was taken from Institutional Review Committee of Kantipur Dental College. Students with prominent veins and without any vascular diseases were included in the study.
Students with thick subcutaneous tissue and cut and wound in cubital region were excluded. Convenience sampling was done and sample size (n) was calculated as, n = Z 2 x p x q / e 2 = (1.96 ) 2 x 0.33 x (1-0.33) / (0.08) 2 = 132.715275 = 133 Where, n= sample size Z= 1.96 at 95% Confidence Interval p= prevalence of Type A venous pattern from the previous study, 33% 3 q= (1-p) e= margin of error, 8% Therefore the minimum required sample size was 133.
Type A cubital venous pattern resembles alphabet M. This pattern includes its subdivisions asType A1 in which median antebrachial vein divides into the median cephalic and median basilic veins, which join the cephalic and basilic vein respectively and Type A2 in which the median cephalic vein does not join with the cephalic vein.Venous patterns were recorded on both right and left arm along with name, sex and age of the student on a proforma. Type A venous pattern and its subdivisions Type A1 and Type A2 obtained were carefully studied and analyzed using Statistical Package for Social Sciences version 20. Point estimate at 95% Confidence Interval was also calculated RESULTS Out of 133 dental students Type A cubital venous pattern was found in 192 arms (72.18%) (64.56-79.79 at 95% CI). Among 133 students, 30 (22.55%) were male students and 103 (77.44%) were female students. The age range of the students was 18-25 years.

CONCLUSIONS
This study showed higher Type A cubital venous pattern among dental students. Knowledge of uncommon patterns of cubital venous patterns is very helpful for medical and paramedical health personnel to prevent injury to underlying structures and for correct intervention of these veins especially during emergency conditions. ACKNOWLEDGMENTS I would like to thank all the students for their participation in conducting this study.