Tumescent solution

[Joshualive2]

Hi for any nurse anesthetist who knows the answer to this I would appreciate the info: Is there a formula that adds up the lidocaine dosage in tumescent fluid used for liposuction and the I.V. lidocaine used during the induction of anesthesia that allows you to find a safe maximum dosage for each when used together? Someone told me there is but I have not been able to find it. Any help would be appreciated. Thanks.

[wtbcrna, MSN, DNP, CRNA]

Hi for any nurse anesthetist who knows the answer to this I would appreciate the info: Is there a formula that adds up the lidocaine dosage in tumescent fluid used for liposuction and the I.V. lidocaine used during the induction of anesthesia that allows you to find a safe maximum dosage for each when used together? Someone told me there is but I have not been able to find it. Any help would be appreciated. Thanks.

Tumescent anesthesia with a lidocaine dose of 55 mg/kg is safe for ... - PubMed - NCBI

[liponurse]

You absolutely would not want to add IV and tumescent local anesthesia lidocaine together to total the maximum of "55mg/kg". The absorption is completely different. Tumescent Lidocaine is absorbed slowly due to the dilute nature and epinephrine which vasoconstricts and holds it in the tissue, releasing it slowly into the blood stream. The peak blood level is about 10-14 hours later. IV lidocaine goes straight to the blood stream. I don't know what the combined effect is....

Also although Jeffrey A. Klein, MD, the inventor of tumescent local anesthesia, at one time stated the maximum was 55 mg/kg, he changed it to 45 mg/kg following further studies. Additionally, one must look at other medications the patient takes as those that inhibit metabolism via the P450 substrate 3A pathway will greatly reduce and slow lidocaine metabolism, leading to a higher blood level and risk of toxicity. Example - a patient taking an SSRI such as Zoloft may not have more than 30-35 mg/kg without increased risk of toxicity. Other risky meds include many anti-fungals, and antibiotics such as erythromycin and cipro.

See tumescent.org for further info

[offlabel]

Any routine iv lidocaine I give doesn't exceed 1mg/kg (that is when I'm treating propofol stinging or coughing on the tube, not ventricular arrhythmias). The elimination half-life is about 100 minutes so whatever dose I give is long gone by the time full absorption occurs from the tumescent solution.

I don't think twice about giving it in this regard. I don't know what the safe upper dose is, but 1/kg is way below that.