Experimental Assessment of the Pre-Analytical Causes of Haemolysis and Their Effects on Serum Electrolytes (Na⁺, K⁺, Cl⁻) and Glucose among Students of Florence Nightingale Higher Institute of Health and Biomedical Sciences Bamenda

Haemolysis remains the most frequently encountered pre-analytical error in clinical laboratories, yet its specific impact on routine biochemical analytes under local laboratory conditions in resource-limited settings like Cameroon is poorly documented. This experimental study assessed the pre-analytical causes of serum haemolysis and their effects on serum electrolytes (Na⁺, K⁺, Cl⁻) and glucose among students of Florence Nightingale Higher Institute of Health and Biomedical Sciences, Bamenda. A total of 21 participants were recruited using convenience sampling. Venous blood samples were collected and divided into control and test portions. Haemolysis was experimentally induced through three pre-analytical manipulations: forcing blood through a needle into the collection tube (T1), vigorous shaking of blood collection tubes (T2), and excessive centrifugation speed (T3). Serum sodium, potassium, and chloride were measured by spectrophotometry, and glucose was determined using a glucometer. Data was analysed using one-way ANOVA, with statistical significance set at p < 0.05. Vigorous shaking produced the highest degree of haemolysis (4+), followed by forcing blood through a needle (3+), while excessive centrifugation caused only mild haemolysis (1+). Potassium concentrations differed significantly across groups (F = 13.90, p < 0.001), with the highest mean in the vigorous shaking group (5.84 ± 1.05 mmol/L) compared to the control (4.26 ± 0.87 mmol/L). Sodium (F = 0.11, p = 0.953) and chloride (F = 0.28, p = 0.84) showed no statistically significant differences across conditions. Glucose levels were likewise unaffected (F = 0.39, p = 0.76). These findings confirm that improper specimen handling, particularly vigorous shaking is a leading driver of in vitro haemolysis and that potassium is the analyte most vulnerable to haemolysis-induced bias, with elevations large enough to produce clinically misleading results. Sodium, chloride, and glucose remained relatively stable under the conditions studied. The study underscores the need for reinforced phlebotomy training, strict adherence to specimen handling protocols, and routine haemolysis monitoring in teaching and clinical laboratories in Cameroon.