The COVID-19 has had a huge impact on the world, infected tens of millions and killed hundreds of thousands, and has become a threat to humanity's medical defense system. COVID-19 was understood as an acute infection among infections, and it was expected that there would be little or no other risk if the acute symptoms were treated. Contrary to our expectations, however, patients with a history of infection with the coronavirus have reported patients with sequelae lasting for more than several months. The symptoms shown by these patients were not limited to some tissues and organs, but were distributed in various ways throughout our body. These symptoms were defined as 'long COVID'. In particular, among the symptoms of long COVID patients, there were patients who were diagnosed with orthostatic hypotension, vasovagal syncope, and orthostatic tachycardia syndrome from symptoms such as palpitations, shortness of breath, and chest pain. What these diseases have in common is that they are autonomic nervous system diseases. Therefore, it can be assumed that long COVID patients have damage to the function of the autonomic nervous system due to past infections, and many studies have been conducted on this.
The main components of general anesthesia are known to be unconsciousness, muscle relaxation, analgesia, and reflex suppression. Among these, the reasons why muscle relaxation is necessary in general anesthesia include ease of intubation and suppression of unnecessary patient movements during surgery to create a suitable environment for surgery. For muscle relaxation, anesthesiologists administer neuromuscular relaxants, mainly non-depolarizing muscle relaxants. Neuromuscular relaxants have the role of inhibiting neurotransmission by acting on the motor nerve endings of skeletal muscles, because they act on nicotinic cholinergic receptors in motor nerve endings. However, neuromuscular relaxants also act on muscarinic cholinergic receptors to inhibit neurotransmission. Since these muscarinic cholinergic receptors are distributed in the parasympathetic nerves of the autonomic nervous system, neuromuscular relaxants also inhibit the autonomic nerve system controlled by the parasympathetic nerves.
Since neuromuscular relaxants are eliminated from the body by pharmacokinetics, the function of the autonomic nervous system, which has been suppressed by using neuromuscular relaxants, gradually recovers over time. However, if the action of a neuromuscular relaxant remains after surgery, the patient will experience autonomic dysfunction even after surgery, which causes considerable discomfort to the patient. Among them, the symptoms of autonomic dysfunction related to the parasympathetic nerve that patients mainly feel are related to the bladder and bowel. Therefore, after the surgery, the anesthesiologist performs the process of reversing the action of the neuromuscular relaxant when ending general anesthesia, which makes it possible to expect the recovery of the patient's autonomic nervous system function.
There are two main mechanisms of the drugs used for reversal of nondepolarizing neuromuscular relaxants. First, there is a drug that inhibits the action of the neuromuscular relaxant by directly attaching to the neuromuscular relaxant, and second, there is a drug that competitively inhibits the neuromuscular relaxant by increasing the amount of ach in the neuromuscular junction. In the meantime, many studies have shown that a drug with the former mechanism (sugammadex) is superior to the latter drug (typically neostigmine) in the recovery of patients after surgery. However, there is a lack of research on whether the same research results will be shown in long COVID patients who have caused damage to the autonomic nervous system.
Therefore, in this study, sugammadex and neostigmine as described above are divided and administered to approximately 300 long COVID patients in a double-blind manner, and the degree of urinary retention is compared to prove that sugammadex is superior to neostigmine in postoperative recovery even for long COVID patients.