#Half life 1.5 skins serial
#Half life 1.5 skins skin

#Half life 1.5 skins serial

3 During this study 1.0% lidocaine with 1:200,000 epinephrine was injected 3 times during multi-stage MMS, and serial plasma lidocaine levels were measured over a surgery span of up to 7.8 hours. demonstrated that the use of nearly the maximum recommended dose of lidocaine during MMS resulted in a maximum plasma concentration of 0.3 ug/ml, which is 10% of the plasma level associated with the mildest signs of lidocaine toxicity. concluded that the use of dilute lidocaine (0.33%) and epinephrine (1:600,000) at a dose 3.1 times higher than the recommended dose of 7 mg/kg resulted in a peak plasma lidocaine level 72% below the safety threshold during facelift procedures. Previous studies, however, have proven the safety of higher lidocaine dosages used in cutaneous surgeries. This re-dosing may result in total lidocaine dosages that exceed the currently recommended maximum dose of 500 mg. 2,3 As subcutaneous lidocaine has a near identical half-life to epidural lidocaine, one could extrapolate that the FDAвЂ™s re-dosing recommendation for epidural lidocaine should also apply to MMS lidocaine subcutaneous use. In fact, FDA administration guidelines for epidural lidocaine allow for re-dosage every 90 minutes if the initial dose does not exceed the safety threshold due to the known half-life of epidural lidocaine of 1.5-2 hours. 3,4 Based on this known half-life, surgeons should be able to safely re-dose after 1.6-2 hours. Lidocaine serum half-life is reported to be 2 hours when injected locally in patients with normal liver function. As one study with a sample of 80 MMS reported, patients may have waiting times that total 1.5 to 3.6 hours, 1 which allow for metabolism of much of the administered lidocaine and may necessitate re-dosing for anesthesia in subsequent stages of surgery. 2 While these recommendations reduce the risk of reaching toxic lidocaine levels, which start at 5 ug/ml, 3 they donвЂ™t account for lidocaine metabolism and clearance that occurs while patients are waiting between MMS stages. The FDA-recommended maximum dosage of lidocaine hydrochloride and epinephrine injection is 7 mg/kg with the maximum total dose not to exceed 500 mg per procedure.

#Half life 1.5 skins skin

When surgeries require excision of large or multiple skin cancers, extensive review of pathology specimens, and/or complex reconstruction, it becomes quite easy for a Mohs surgeon to exceed the FDA-recommended lidocaine dosage. Current FDA guidelines for lidocaine use in Mohs micrographic surgery (MMS) do not account for the lengthy duration of MMS, which is on average 2-4 hours, nor for the need for lidocaine supplementation during multiple stages of cutaneous resection and reconstruction.