Naphazoline nitrate

A specific and reliable high-performance thin layer chromatography method with densitometry detection has been developed for the determination of naphazoline nitrate in nasal drops. The best separation of the basic analyte, without spot tailing, was achieved by using a mobile phase composed of acetonitrile-water (60:40, v/v), adding 1.5 % (v/v) imidazolium-class ionic liquid and covering the plates with a stationary phase based on RP-18 with F254S (10 × 20 cm). The presented results confirm that imidazolium tetrafluoroborate ionic liquids are efficient suppressors of free silanols, which are considered to be responsible for troublesome and irreproducible chromatographic determinations of basic compounds. The developed chromatographic system was found to be convenient in use and to provide a repeatable assay of naphazoline nitrate in nasal drops, which could not be obtained with the use of standard silanol suppressing mobile phase additives such as triethylamine or dimethyloctylamine.

Septorhinoplasty is a traumatic procedure that is associated with epistaxis and postoperative pain. The primary objective of this randomized double-blind controlled trial was to determine whether intranasal 5% lidocaine plus naphazoline decreases postoperative pain and lessens the use of rescue analgesics.

After induction of general anesthesia and laryngeal topical anesthesia with 5% lidocaine, 28 adult patients, scheduled to undergo septorhinoplasty, were randomly assigned to one of two groups, either topical intranasal saline 20 ml (control group) or intranasal 5% lidocaine plus naphazoline solution 0.2 mg ml(-1) (lidocaine group). The perioperative dose of sufentanil, the mean end-tidal concentration of isoflurane, and surgeon satisfaction with the operative field were recorded. In the lidocaine group, plasma lidocaine concentrations were sampled 15, 20, 25, 35, 45, and 55 min after induction of anesthesia. Visual analogue scale pain scores were recorded 30, 60, 90, and 120 min after the patients arrived in the postanesthesia care unit and 24 h after surgery. Consumption of morphine rescue analgesia and the occurrence of any side effects were recorded at the end of the 24-h study period.

The intranasal lidocaine-naphazoline application decreased isoflurane requirements [median values: 0.8% (0.7-1.5) vs. 1.2% (0.9-1.8), respectively; P = 0.04] and enhanced surgical conditions. Patients in the lidocaine group experienced less postoperative pain than the control group [1 h after surgery: median values of visual analogue scale: 0 (0-20) vs. 50 (30-80), respectively; P = 0.001], and they required fewer doses of subcutaneous morphine. Total plasma concentrations of lidocaine remained below 4 microg ml(-1) throughout the study period.

Intranasal lidocaine plus naphazoline is a simple and efficient technique for decreasing intra- and postoperative pain and for lessening rescue analgesic requirements in the postoperative period after septorhinoplasty. Toxic plasma concentrations of lidocaine were not reached.