Epinephrine one-per-mil tumescent solution in hand surgery: Review of experimental and clinical studies

One-per-mil epinephrine solution (1:1,000,000) injected as a tumescent has been used in several hand and upper-limb surgery cases as a substitute for tourniquet. However, reviews of its effectiveness are still lacking. A comprehensive review was conducted based on PubMed, Scopus, Science Direct, Cochrane Library, and Semantic Scholar database search of relevant studies using the keyword "one-per-mil." Studies not using the exact one-per-mil tumescent solution formula were excluded. The review of clinical studies was conducted according to PRISMA guidelines. Epinephrine and the hydrostatic vasocompressive effect created bloodless operative fields, with 100% experimental flap survival after ischemic insult. The technique was effective in creating bloodless operative fields in 36.3% of varied hand and upper-limb surgery cases and in fully awake surgery. Current studies show that one-per-mil tumescent solution is safe and effective, enabling use of tourniquet to be avoided.

Laboratory Study on Injection Force Measurement on Syringe and Needle Combinations

Background

This study aimed to measure the least initial and maintenance forces of syringe and needle combinations to provide a reference for local anesthetic injection.

Methods

An experimental study was conducted in our Physics Laboratory during September 2015. A series of syringes sized 1 mL, 3 mL, 5 mL, 10 mL and 20 mL were paired with the original needles, 27G, 27G spinal and 30G. Each combination was tested three times using a compression testing Instron 5940 Series to measure initial and maintenance forces. Statistical analysis was performed using One-way ANOVA.

Results

The lowest initial force was shown by the combination of 1 mL syringe and 27G spinal needle. However, the 1 mL syringe showed no significant difference across the needles [F(3, 8) = 3.545; P < 0.068]. The original and 27G needle showed mean difference 0.28 (95%CI: −0.19, 0.75; P = 0.420). The lowest maintenance force was measured in the combination of 1 mL syringe and its original 26G needle. On the contrary, both the highest initial and maintenance forces were shown by the combination of 10 mL syringe and 30G needle.

Conclusion

The 1 mL syringe with original 26G needle shows the best combination.

Prevention of Surgical Site Infections and Biofilms: Pharmacokinetics of Subcutaneous Cefazolin and Metronidazole in a Tumescent Lidocaine Solution

BACKGROUND

Tumescent anesthesia antibiotic delivery (TAAD) consists of subcutaneous infiltration of antibiotic(s) dissolved tumescent lidocaine anesthesia. Tumescent lidocaine anesthesia contains lidocaine (≤ 1 g/L), epinephrine (≤ 1 mg/L), sodium bicarbonate (10 mEq/L) in 0.9% saline. Our aim was to measure cefazolin and metronidazole concentrations over time in subcutaneous tumescent interstitial fluid (TISF) after TAAD, in serum after TAAD and after intravenous antibiotic delivery (IVAD). We hypothesize that the pharmacokinetic/pharmacodynamic profiles of TAAD + IVAD are superior to IVAD alone for the prevention of surgical site infections and biofilms.

METHODS

Concentrations of cefazolin and metronidazole in TISF and serum following TAAD and in serum following IVAD were compared in 5 female volunteers. Subjects received cefazolin or cefazolin plus metronidazole by IVAD alone and by TAAD alone. One subject also received concomitant IVAD and TAAD of these 2 antibiotics. Sequential samples of serum or subcutaneous TISF were assayed for antibiotic concentration.

RESULTS

Cefazolin (1 g) by TAAD resulted in an area under the curve of the concentration-time profile and a maximum concentration (Cmax) in subcutaneous tissue that were 16.5 and 5.6 times greater than in serum following 1 g by IVAD. Metronidazole (500 mg) by TAAD resulted in an area under the curve and Cmax that were 8.1 and 24.7 times greater in TISF, than in serum after 500 mg by intravenous delivery. IVAD + TAAD resulted in superior antibiotic concentrations to IVAD alone.

CONCLUSIONS

TAAD + IVAD produced superior antibiotic bioavailability in both subcutaneous interstitial fluid and serum compared with IVAD alone. There was no evidence that TAAD of cefazolin and metronidazole poses a significant risk of harm to patients.