A portable, electrically-powered automated or semi-automated laboratory instrument intended to be used for the qualitative and/or quantitative in vitro measurement of multiple clinical chemistry analytes to generate a metabolic profile. Analytes may include pH, blood gas parameters (e.g., pO2, pCO2), electrolytes [e.g., Sodium (Na2+), potassium (K+), chloride (Cl-)], glucose, urea, creatinine and sometimes in addition haemoximetry parameters [e.g., carboxy-haemoglobin (COHb), methaemoglobin (MetHb), total haemoglobin (totHb), hematrocrit (Hct)].