If a physician has ruled out these serious causes of chest pain, other causes may be explored. Common causes of upper back pain that do not involve the spine include: Heart attack. Pneumonia and pleuritis. High blood pressure. Fibromyalgia (widespread muscle pain and tenderness) or other chronic pain syndromes.
1 The normal potassium level in the blood is 3.5-5.0 milliEquivalents per liter (mEq/L). 2  Potassium levels between 5.1 mEq/L to 6.0 mEq/L are considered to be mild hyperkalemia. 3  Potassium levels of 6.1 mEq/L to 7.0 mEq/L are moderate hyperkalemia, and levels above 7 mEq/L reflect s evere hyperkalemia.t is also important for maintaining normal heart electrical rhythm and for normal electrical signals in the nervous system. 1  The normal potassium level in the blood is 3.5-5.0 milliEquivalents per liter (mEq/L).
Blood. 1  Plasma: the normal plasma concentration of potassium or kalemia is 4.2 mmol/L. 2  Red cells: the erythrocytes are very rich in potassium, they contain approximately 90 mmol/L.