To detect the effect of time delay and syringe surface area on the oxygen tension (PaO2), oxyhaemoglobin saturation (SaO2), acidity (pH), and carbon dioxide tension (PaCO2) in both arterial and venous blood gas outcomes.

Arterial blood gas (ABG) analysis and monitoring is a crucial process for the diagnosis and management of the oxygenation status and acid-base balance of high-risk patients during surgery, as well as for the critical care of critically ill patients in the Intensive Care Unit .

Acid-base imbalance anomalies can have major repercussions in a number of medical scenarios, and in a few rare instances, they may even be a risk factor for death.

ABG test explores the arterial blood's pH, oxyhaemoglobin saturation (SaO2), bicarbonate concentration (HCO3), oxygen tension (PaO2), and carbon dioxide tension (PaCO2).

Traditionally, the concept "blood gas testing" has been used to describe measuring the blood's pH, oxygen saturation of haemoglobin (SaO2), and partial pressures of the physiologically active gases (pO2, pCO2). But now available commercial equipment can measure electrolytes (sodium, potassium, chloride, ionized calcium, and magnesium), glucose, lactate, and creatinine, usually all at the same time, in addition to haemoglobin quantification and co-oximetry

Inclusion Criteria:

• Critically ill-patients, and intraoperative patients who aged above 18 years.

Exclusion Criteria:

• Patients with haematological diseases e.g. sickle cell anaemia
• burn patients with risk of carbon monoxide poisoning
• ARDS
• pulmonary oedema
• samples that were clotted

Critically ill-patients, and intraoperative patients who aged above 18 years.

The data will be available upon a reasonable request from the corresponding author after the end of study for one year.

after the end of the study for one year

The data will be available upon a reasonable request from the corresponding author.