Physicochemical stability of ternary admixtures of butorphanol, ketamine, and droperidol in polyolefin bags for patient-controlled analgesia use

Figures & data

Table 1 Validation of HPLC method

Compound	Measured concentrations (μg/mL)	Accuracy (%)	Precision RSD (%)
			Intraday	Interday
Butorphanol tartrate	5.0	98.1	0.6	1.4
	12.5	101.8	0.9	2.1
	25.0	100.9	1.2	1.7
Ketamine hydrochloride	125.0	101.2	0.3	0.8
	250.0	100.5	0.8	1.2
	500.0	102.1	1.5	2.5
Droperidol	5.0	101.7	0.5	0.9
	7.5	100.3	0.7	1.6
	12.5	98.5	0.4	1.1

Abbreviations: HPLC, high-performance liquid chromatography; RSD, relative standard deviation.

Figure 1 Chromatograms of standard drug mixture samples obtained after 20 μL direct injection. Peak 1: ketamine hydrochloride; peak 2: butorphanol tartrate; peak 3: droperidol.

Abbreviation: mAU, milli absorbance unit.

Table 2 Stability of butorphanol tartrate, ketamine hydrochloride, and droperidol in 0.9% sodium chloride stored in polyolefin bags at 4°C

Drug	Initial concentration (μg/mL)a	Percentage initial concentration remaininga (mean ± SD)
		Day 1	Day 3	Day 5	Day 7	Day 10	Day 14
Butorphanol tartrate	66.9±0.95	100.2±1.2	102.5±2.4	98.6±1.3	99.9±0.3	99.4±0.2	100.2±0.4
Ketamine hydrochloride	1,352±38.2	101.8±0.7	98.7±0.6	102.0±1.9	102.3±1.5	99.8±0.5	99.1±1.1
Droperidol	35.1±1.62	99.8±0.9	101.5±1.4	99.5±0.3	102.4±2.1	98.8±1.0	98.2±1.2

Note:

a n=3.

Abbreviation: SD, standard deviation.

Table 3 Stability of butorphanol tartrate, ketamine hydrochloride, and droperidol in 0.9% sodium chloride stored in polyolefin bags at 25°C

Drug	Initial concentration (μg/mL)a	Percentage initial concentration remaininga (mean ± SD)
		Day 1	Day 3	Day 5	Day 7	Day 10	Day 14
Butorphanol tartrate	67.0±0.80	100.2±1.4	99.7±1.2	101.5±2.0	101.2±1.1	100.8±0.4	99.2±1.6
Ketamine hydrochloride	1,395±83.2	101.1±1.6	100.2±1.7	98.3±0.8	99.1±0.4	98.2±1.3	98.7±0.5
Droperidol	34.3±1.91	102.5±2.4	98.7±1.4	99.2±0.6	101.0±1.2	100.0±0.7	101.9±0.9

Note:

a n=3.

Abbreviation: SD, standard deviation.