Pseudocholinesterase deficiency is a condition that results in increased sensitivity to certain muscle relaxant drugs used during general anesthesia.
Normally, these drugs are broken down (metabolized) by the body within a few minutes of being administered, thanks to the action of pseudocholinesterase, a protein present in the muscles which breaks down the molecules of the drug. Normally, these drugs are broken down (metabolized) by the body within a few minutes of being administered and eliminated.
Pseudocholinesterase deficiency is a relatively frequent disorder that appears in approximately one of every 4000 persons. In some cases, it is caused by an autosomal recessive genetic mutation transmitted from parents to children. This means that the a person can be a carrier of said mutation without manifesting the disorder but if both parents are carriers of the mutation and have children, the children will inherit the mutation from both and will have pseudocholinesterase deficiency.
Nonetheless, not all cases are a result of genetic mutations; some chronic infections, severe extensive burns, hepatic illnesses, some cancers, malnutrition or determined medicines can also cause pseudocholinesterase deficiency.
When the patient has pseudocholinesterase deficiency, the muscle relaxants remain active too long and may not be able to move or breathe on his/her own for a few hours after the drugs are administrated. Since the diaphragm is the principal muscle in the breathing function, when muscle relaxants are administered, pseudocholinesterase deficiency also affects the ability to breathe, necessitating mechanical ventilation for a longer time than the normal.
Currently there are no effective measures to prevent pseudocholinesterase deficiency, but there are blood analysis and genetic tests to detect it. The persons who have this disorder should avoid this type of muscle relaxant. If it is unavoidable, the treatment consists of using mechanical ventilation while the drugs are effective and wait until they are eliminated from the body.
Gene or region studied