01 July 2024 : Review article
The Influence of Acid-Base Balance on Anesthetic Muscle Relaxants: A Comprehensive Review on Clinical Applications and Mechanisms
Paweł Radkowski
123ABCDEFG, Maciej Szewczyk 4ABCDEFG*, Aleksandra Czajka 12F, Milena Samiec 12F, Małgorzata Braczkowska-Skibińska 1FG
DOI: 10.12659/MSM.944510
Med Sci Monit 2024; 30:e944510
Introduction
Acid-Base Balance Disturbances
Characteristic of Non-Depolarizing Muscle Relaxants
The Use of Non-Depolarizing Muscle Relaxants in Acidosis and Alkalosis
Characteristic of Depolarizing Muscle Relaxants
The Use of Depolarizing Muscle Relaxants in Acidosis and Alkalosis
Monitoring and Management
Use of Muscle Relaxants in Metabolic and Neuromuscular Disorders
Future Directions
Conclusions
References
Table 4 Division of NMBDs based on their action and elimination mechanism from the body.
| Group of relaxants | Onset of action [min] | Duration of action [min] | ED95 | Pathways of metabolic degradation and excretion |
|---|---|---|---|---|
| Mivacurium | 1–1.5 | 15–20 | 0.08 mg/kg | Plasma pseudocholinesterase (butyrylcholinesterase);excretion by kidneys |
| Gantacurium | 10 | 0.19 mg/kg | Alkaline hydrolysis | |
| Rocuronium | 1–3 | 30–60 | 0.3 mg/kg | Excreted unchanged in bile and in around 30% by kidneys |
| Cisatracurium | 2 | 60–90 | 0.05 mg/kg | Hofmann elimination and ester hydrolysis;Only 23% is excreted in organ-depended manner - mostly by kidneys |
| Atracurium | 1–1.5 | 45–60 | 0.23 mg/kg | Two-thirds is degraded by ester hydrolysis and one-third by Hofmann reaction; less than 5% of atracurium is excreted by kidneys; prime metabolite – laudanosine (which presents no neuromuscular blocking activity) is excreted by liver and by kidneys |
| Vecuronium | 1.5 | 60 | 0.05 mg/kg | Metabolized by the liver to 3-desacetylvecuronium, 17-desacetylvecuronium, and 3.17-desacetylvecuronium; excretion of unmetabolized vecuronium: 40% is cleared through the bile and 20% to 30% is eliminated by kidneys 5% is excreted in the urine as the 3-desacetyl metabolite |
| Long-acting | ||||
| Pipecuronium | 3–5 | 80–90 | 0.05 mg/kg | Little metabolized; excreted mainly by kidneys – about 40% of pipecuronium is excreted unchanged by kidneys together with another 15% as 3-hydroxypipecuronium in 24 hours |
| Pancuronium | 4–5 | 90 | 0.07 mg/kg | Excretion by kidneys in 80%; hepatic degradation in 10% and biliary excretion in 10% |
| NMBDs – non-depolarizing muscle drugs; ED95 – effective dose 95 (dose expected to reduce single twitch height by 95%). | ||||