Safe and effective use of a passive safety needle by healthcare professionals in a simulated environment, including perceptions and preferences

Figures & data

Figure 1. Passive safety needle, available in eight different needle gauges (0.3–1.3 mm) and lengths (13, 16, or 25 mm). A-Outer cover; B-Needle; C-Entire needle length penetrating the skin (L); D-Safety shield; E-Needle use indicator; F-Colored needle hub. This passive system means that the device does not require any activity of the user and is activated automatically during the movement of the needle slider when the needle is inserted into the tissue. The needle is packed in a cover that functions as an additional protection against accidental activation and blocking of the needle. When a user removes the cover, the needle is contained within the safety shield. When administering the injection, the safety shield retracts while the needle inserts into the skin. After injection, the needle automatically locks within the safety shield, preventing further use. When the safety mechanism is activated, a red indicator appears.

Table 1. Results from two usability and safety studies of the passive safety needle in nurses, pharmacists, and physicians (studies 1&2).

	Study 1, n (%)				Study 2, n (%)
	UG1	UG2	UG3	Total	UG1	UG2	UG3	Total
No. participants	15	10	5	30	24	24	6	54
Tasks performed	570	380	190	1140 (100)	1392	1392	348	3132 (100)
Success^a	433 (75.96)	278 (73.16)	124 (65.26)	835 (73.25)	1234 (88.65)	1213 (87.14)	313 (89.94)	2760 (88.12)
Close calls^b	4 (0.70)	5 (1.32)	2 (1.05)	11 (0.96)	9 (0.65)	20 (1.44)	3 (0.86)	32 (1.02)
Difficulties^c	6 (1.05)	9 (2.37)	6 (3.16)	21 (1.84)	16 (1.15)	12 (0.86)	5 (1.44)	33 (1.05)
Use errors^d	127 (22.28)	88 (23.16)	58 (30.53)	273 (23.95)	133 (9.55)	147 (10.56)	27 (7.76)	307 (9.8)

^aThe participant was able to complete the task correctly and as intended. ^bThe participant deviated from correct task completion initially or made a use error that could result in harm, but swiftly managed to recover, self-correct and complete the task as intended, preventing harm from occurring. ^cThe participant experienced difficulty and delay completing the task as intended, but self-corrected to complete the task, without the lead investigators intervention. ^dThe participant was unable to complete the task as intended or where the task was temporarily halted, or the Moderator had to intervene for the task to be completed. Abbreviations: UG (user group) 1, nurses; UG2, pharmacists; UG3, physicians.

Table 2. Characteristics of participants in a usability and safety study of the passive safety needle in nurses, pharmacists, and physicians (Study 3).

	Participants
Total number of participants, n	20
Nurses	10
Pharmacists	5
Physicians	5
Total number of devices, n	500
Nurses	250
Pharmacists	125
Physicians	125
Age (years), average (range)	49.8 (30–65)
Frequency of administering injections to patients, n
5–10 times per week	6
10–25 times per week	7
25+ times per week	7
Length of experience using active and/or passive needles, n
2–10 years	9
10–15 years	7
15+ years	4
Handedness, n
Right-handed	17
Left-handed	2
Ambidextrous	1
Visual impairments, n
None	6
Corrected – glasses for reading	5
Corrected – glasses for reading and distance	3
Corrected – glasses for distance	1
Corrected – contacts	5

Table 3. Most problematic errors, difficulties, and close calls encountered that were deemed safety critical* in the usability and safety studies of the passive safety needle in nurses, pharmacists, and physicians (studies 1&2).

	Study 1 (1140 tasks, 30 participants)	Study 2 (1392 tasks, 54 participants)
Total use errors, no. tasks (no. participants)	273 (30)	307 (51)
Verify integrity	69	105^a
Check expiry date	84	129
Prime needle	78	—
Peel blister pack of the needle halfway using aseptic technique	20	—
Read instructions before use	11	14
Wash your hands before using the device	—	22
Total difficulties, no. tasks (no. participants)	21	33
Administration using 13 mm x 30 G (45° angle with skin fold)	2	—
Administration using 13 mm x 30 G (45° angle without skin fold)	3	—
Administration Using 16 mm x 25 G (90-degree angle with skin fold)	2	—
Attach passive safety needle to a luer slip/lock syringe filled with the drug by pushing when attaching to luer slip syringe or by twisting and screwing on luer lock syringe	7	—
Select injection site and position passive safety needle at a 45° angle at the injection site to administer the drug	—	2
Hold the desired angle of 45° while pushing the needle in one continuous movement to administer the drug	—	3
Fill the syringe (5 ml) with the drug using a blunt fill needle	—	2
Select injection site and position passive safety needle at a 90° angle at the injection site to administer the drug	—	2
Hold the desired angle of 90° while pushing the needle in one continuous movement to administer the drug	—	5
Total close calls, no. tasks (no. participants)	11 (30)	32 (19)
Read the instructions before use	4	7
Select the correct needle size and syringe for the medication being prescribed	3	—
Fill the syringe with the drug using a blunt fill needle	—	14

*Safety critical=a user task which, if performed incorrectly or not performed at all, would or could cause serious harm to the patient or user, where harm is defined to include compromised medical care. ^aVerify integrity of the blister pack, n = 49; verify integrity of the device, n = 56.

Figure 2. Evaluation of usability of the passive safety needle across all participants in a) Study 1 and b) Study 3. The values above the columns are number of patients in Study 1 and average rating in Study 3. * in Study 3: 17 right-handed evaluators and one ambidextrous evaluator (who performed all 25 injections with their right hand) responded to statement no. 10; two left-handed evaluators responded to statement no. 11.

Table 4. Overall evaluation of the passive safety needle by the participants (Study 1).

	Rating (n)*
Question	Very bad	Bad	Normal	Good	Very good	‘Good’ and ‘Very Good’ %
What is your general impression of the device for subcutaneous injections with a 13 mm needle?	0	6	4	9	11	67%
What is your general impression of the device for subcutaneous injections with a 16 mm needle?	0	0	7	10	13	77%
What is your general impression of the device for intramuscular injections with a 25 mm needle?	0	2	1	7	20	90%

*n = 30 participants.

Figure 3. Responses provided in the perception and preference study for questions relating to the perception of nurses, pharmacists, and physicians for the passive safety needle. Please refer to the Supplementary table for the corresponding questions.

Figure 4. Perceptions of the safety of the passive safety needle compared to an active syringe, active safety needle, or retractable needle/syringe (Q17 on the questionnaire). User group (UG)1, nurses; UG2, pharmacists; UG3, physicians.