Observational Study of Peripheral Intravenous Catheter Outcomes in Adult Hospitalized Patients: A Multivariable Analysis of Peripheral Intravenous Catheter Failure

Dislodgement

Statistically significant predictors associated with an increased risk of PIV dislodgement included paramedic insertion (HR, 1.78; 95% CI, 1.03-3.06) and frequent PIV access (HR, 1.11; 95% CI, 1.03-1.20). A decreased risk was associated with the additional securement of the PIV, including nonsterile tape (HR, 0.44; 95% CI, 0.31-0.63) or other forms of additional securement (HR, 0.32; 95% CI, 0.22-0.46).

One in 3 PIVs failed in this study, with phlebitis as the most common cause of PIV failure. The 17% phlebitis rate reflected clinician-reported phlebitis or phlebitis observed by research staff using a 1-criteria definition because any sign or symptom can trigger PIV removal (eg, pain), even if other signs or symptoms are not present. Reported phlebitis rates are lower if definitions require 2 signs or symptoms.^4,6 With over 71 different phlebitis assessment scales in use, and none well validated, the best method for diagnosing phlebitis remains unclear and explains the variation in reported rates.²⁵ Occlusion/infiltration and dislodgement were also highly prevalent forms of PIV failure at 14% and 10%, respectively. Occlusion and infiltration were combined because clinical staff use these terms interchangeably, and differential diagnostic tools are not used in practice. Both result in the same outcome (therapy interruption and PIV removal), and this combination of outcomes has been used previously.²³ No PIV-associated bloodstream infections occurred, despite the heightened awareness of these infections in the literature.³

Females had significantly more occlusion/infiltration and phlebitis than males, in keeping with previous studies.^7,9,10 This could be because of females’ smaller vein caliber, although the effect remained after adjustment for PIV gauge.^7,26 The effect of aging on vascular endothelium and structural integrity may explain the observed decrease in phlebitis of 1% with each older year of age.²⁷ However, gender and age effects could be explained by psychosocial factors (eg, older people may be less likely to admit pain, or we may question them less sympathetically), but, regardless, women and younger patients should be monitored more closely.

We found 22-gauge catheters were more likely to fail from occlusion/infiltration than other sizes. This confirms similar findings from Abolfotouh et al.⁹ PIV gauge selection for this study was made at the inserter’s discretion and may be confounded by smaller vein size, which was not measured. In addition, risk may be because of smaller gauge alone or also more influenced by the shorter length of the studied 22-gauge (25 mm) than the <20-gauge catheters (30 mm). These results question international guidelines, which currently recommend the smallest gauge peripheral catheter possible,^28,29 and randomized trials are needed. Although practice varies between inserters, some preferentially cannulate the nondominant limb. We are not aware of previous studies on this practice; however, our results support this approach.

Flucloxacillin was associated with a 2-fold increase in occlusion/infiltration and phlebitis. Although multiple studies have reported IV medications^9,11 and IV antibiotics^10,30,31 as risk factors for PIV failure, none have identified flucloxacillin as an independent risk factor. IV flucloxacillin is recommended for reconstitution as 1 g in 15 mL to 20 mL of sterile water, and injection over 3 to 4 minutes, although this may not be adhered to in practice. Alternative administration regimes or improved adherence to current policy may be needed. An exception to the relationship between IV antibiotics and catheter failure was IV cephazolin, associated with 40% relatively less phlebitis. This may be a spurious finding because the administration, pH, and osmolality of cephazolin are similar to other IV antibiotics.

The more PIVs that were accessed per day, whether for infusions or medications, the more failure occurred from occlusion/infiltration, phlebitis, and dislodgement. This suggests that peripheral veins are easily damaged and/or inflamed by the influx of fluids or medications. Lower injection pressures or the timely transfer to oral medications may limit this problem. Flushing regimens may also assist because practice varies greatly, and questions on whether slow continuous flush infusion or intermittent manual flushing are more vein-protective, and the optimal flush volume, frequency, and technique (eg, pulsatile) remain.^32,33 Manual handling for frequent access may loosen dressings and securement, thus explaining the observed association between frequent access and catheter dislodgement. Finally, the association between use and failure may indicate that many of these patients were not suitable for a PIV, and different approaches (eg, ultrasound-guided insertion) or a midline may have been a superior option. There is growing emphasis on the need for better preinsertion assessment and selection of the most appropriate device for the patient and the IV treatment required.³⁴

Suboptimal dressings or securements are not unusual in hospitals.³⁵ Despite our policy of PIV securement with bordered transparent dressings, we found 4 dressing types in use. In addition, we found almost 50% of PIVs had an additional (secondary) securement, and this was associated with significantly less PIV failure of all 3 types. This suggests that 1 or more of nonsterile tape, elasticized tubular bandages, or other securement (eg, bandage or second transparent dressing) can reduce PIV failure, although a randomized trial is lacking.³⁶ Whether the dressing was failing and required reinforcement or hospital staff lacked confidence in the dressing and placed additional securement preventatively is unclear. Both PIV failure and PIV dressing failure are common, and further research into superior PIV products and practices is urgently needed. Paramedic insertions had a higher risk of dislodgement, suggesting that the increased emphasis on securement should start in the prehospital setting.

While multiple or difficult insertion attempts were not associated with PIV failure, insertions were not directly observed, and clinicians may have underreported attempts. In contrast, insertion-related bruising (a surrogate for difficult insertion) was associated with more than double the incidence of phlebitis. The long-term implications of multiple insertion attempts on patient’s vasculature are unclear, but we believe first time PIV insertion is important to patients and of interest to clinicians. A recent systematic review of strategies associated with first attempt PIV insertion success in an emergency department found little evidence for effective strategies and recommended further research.³⁷

The overall PIV failure rate in our study was 32%, lower than the 35% to 40% failure observed in our previous randomized controlled trials, which had more stringent inclusion and exclusion criteria (eg, longer predicted duration of therapy).^6,38 The implications for patients and costs to the organization of frequent catheter replacement demonstrate urgent need for further research in this area of practice.³⁹ A strength of this study is that all PIVs, regardless of the expected length of dwell time or reason for insertion, were eligible for inclusion, providing more generalizable results. The PIV failure rate of 32% is concerning because these failures trigger treatment delays and replacement insertions, with significant increased labor and equipment costs. The mean cost of PIV replacement has been costed at AUD $69.30 or US $51.92 (as per 2010 $ value) per episode of IV treatment.⁴⁰ For our hospital, which uses 200,000 PIVs per year, the current level of PIV failure suggests almost AU $5.5 (US $4.1) million in waste annually at this site alone.

The additional strengths of this study include the extensive information collected prospectively about PIV insertion and maintenance, including information on who inserted the PIV, IV medications administered, and PIV dressings used. Limitations were the population of surgical and medical patients in 1 tertiary hospital, which may not be generalizable to other settings.