Observational Study of Peripheral Intravenous Catheter Outcomes in Adult Hospitalized Patients: A Multivariable Analysis of Peripheral Intravenous Catheter Failure
BACKGROUND: Almost 70% of hospitalized patients require a peripheral intravenous catheter (PIV), yet up to 69% of PIVs fail prior to completion of therapy.
OBJECTIVE: To identify risk factors associated with PIV failure.
DESIGN: A single center, prospective, cohort study.
SETTING: Medical and surgical wards of a tertiary hospital located in Queensland, Australia.
PARTICIPANTS: Adult patients requiring a PIV.
MEASUREMENTS: Demographic, clinical, and potential PIV risk factors were collected. Failure occurred if the catheter had complications at removal.
RESULTS: We recruited 1000 patients. Catheter failure occurred in 512 (32%) of 1578 PIVs. Occlusion/infiltration risk factors included intravenous (IV) flucloxacillin (hazard ratio [HR], 1.98; 95% confidence interval [CI], 1.19-3.31), 22-gauge PIVs (HR, 1.43; 95% CI, 1.02-2.00), and female patients (HR, 1.48; 95% CI, 1.10-2.00). Phlebitis was associated with female patients (HR, 1.81; 95% CI, 1.40-2.35), bruised insertion sites (HR, 2.16; 95% CI, 1.26-3.71), IV flucloxacillin (HR, 2.01; 95% CI, 1.26-3.21), and dominant side insertion (HR, 1.39; 95% CI, 1.09-1.77). Dislodgement risks were a paramedic insertion (HR, 1.78; 95% CI, 1.03-3.06). Each increase by 1 in the average number of daily PIV accesses was associated (HR 1.11, 95% CI 1.03-1.20)–(HR 1.14, 95% CI 1.08-1.21) with occlusion/infiltration, phlebitis and dislodgement. Additional securement products were associated with less (HR 0.32, 95% CI 0.22-0.46)–(HR 0.63, 95% CI 0.48-0.82) occlusion/infiltration, phlebitis and dislodgement.
CONCLUSION: Modifiable risk factors should inform education and inserter skill development to reduce the currently high rate of PIV failure.
© 2017 Society of Hospital Medicine
Statistical Analysis
Data were downloaded from REDcap to Stata 14.2 (StataCorp., College Station, TX) for data management and analysis. Missing data were not imputed. Nominal data observations were collapsed into a single observation per device. Patient and device variables were described as frequencies and proportions, means and standard deviations, or medians and interquartile ranges. Failure incidence rates were calculated, and a Kaplan-Meier survival curve was plotted. In general, Cox proportional hazards models were fitted (Efron method) to handle tied failures (clustering by patient). Variables significant at P < 0.20 on univariable analyses were subjected to multivariable regression. Generally, the largest category was set as referent. Correlations between variables were checked (Spearman’s rank for binary variables, R-squared value of linear regressions for continuous/categorical or continuous/continuous variables). Correlations were considered significant if r > 0.5 and the lower bound of the 95% confidence interval (CI) was >0.5 (where calculated). Covariate interactions were explored, and effects at P < 0.05 noted. The 4 steps of multivariable model building were (1) baseline covariates only with manual stepwise removal of covariates at P ≥ 0.05, (2) treatment covariates only with manual stepwise removal of covariates at P ≥ 0.05, (3) a combination of the derived models from (1) and (2) and manual stepwise removal of covariates at P ≥ 0.05, and (4) manual stepwise addition and removal (at P ≥ 0.05) of variables dropped during the previous steps and interaction testing. Final models were checked as follows: global proportional-hazards assumption test, concordance probability (that predictions and outcomes were in agreement), and Nelson-Aalen cumulative hazard function plotted against the Cox-Snell residuals.
RESULTS
Patient Characteristics
In total, 1000 patients with 1578 PIVs were recruited. The average age was 54 years and the majority were surgical patients (673; 67%). Almost half of patients (455; 46%) had 2 or more comorbidities, and 334 (33%) were obese (body mass index greater than 30). Sample characteristics are shown by the type of catheter failure in Table 1.
PIV Characteristics
All 1578 PIVs were followed until removal, with only 7 PIVs (0.44%) having missing data for the 3 outcomes of interest (these were coded as nonfailures for analysis). Sixty percent of participants had more than 1 PIV followed in the study. Doctors and physicians inserted 1278 (83%) catheters. A total of 550 (35%) were placed in the ward, with 428 (28%) inserted in the emergency department or ambulance. A third of the catheters (540; 34%) were 18-gauge or larger in diameter, and 1000 (64%) were located in the cubital fossa or hand. Multiple insertion attempts were required to place 315 (23%) PIVs. No PIVs were inserted with ultrasound, as this is rarely used in this hospital. The flushing policy was for the administration of 9% sodium chloride every 8 hours if no IV medications or fluids were ordered. Table 2 contains further details of device-related characteristics. Although the hospital policy was for catheter removal by 72 hours, dwell time ranged from <1 to 14 days, with an average of 2.4 days.
PIV Complications
Catheter failure (any cause) occurred in 512 (32%) catheters, which is a failure rate of 136 per 1000 catheter days (95% CI, 125-148). A total of 346 patients out of 1000 (35%) had at least 1 failed PIV during the study. Failures were 267 phlebitis (17%), 228 occlusion/infiltration (14%), and/or 154 dislodgement (10%; Figure), with some PIVs exhibiting multiple concurrent complications (Table 2).
Multivariable AnalysisOcclusion/Infiltration
The multivariable analysis (Table 3) showed occlusion or infiltration was statistically significantly associated with female patients (hazard ratio [HR], 1.48; 95% CI, 1.10-2.00), with a 22-gauge catheter (HR, 1.43; 95% CI, 1.02-2.00), IV flucloxacillin (HR, 1.98; 95% CI, 1.19-3.31), and with frequent PIV access (HR, 1.12; 95% CI, 1.04-1.21; ie, with each increase of 1 in the mean medications/fluids administrations per day, relative PIV failure increased 112%). Less occlusion and infiltration were statistically significantly associated with securement by using additional nonsterile tape (HR, 0.46; 95% CI, 0.33-0.63), elasticized tubular bandages (HR, 0.49; 95% CI, 0.35-0.70 ), or other types of additional securement for the PIV (HR, 0.35; 95% CI, 0.26-0.47).
Phlebitis
Phlebitis was statistically significantly associated with female patients (HR, 1.81; 95% CI, 1.40-2.35), bruising at the insertion site (HR, 2.16; 95% CI, 1.26-3.71), insertion in patients’ dominant side (HR, 1.39; 95% CI, 1.09-1.77), IV flucloxicillin (HR, 2.01; 95% CI, 1.26-3.21), or with frequent PIV access (HR, 1.14; 95% CI, 1.08-1.21). Older age, (HR, 0.99; 95% CI, 0.98-0.99; ie, each year older was associated with 1% less phlebitis), securement with additional nonsterile tape (HR, 0.63; 95% CI, 0.48-0.82) or with any other additional securement (HR, 0.53; 95% CI, 0.39-0.70), or the administration of IV cephazolin (HR, 0.63; 95% CI, 0.44-0.89) were associated with lower phlebitis risk.
