Incidence of peripheral intravenous catheter phlebitis and its associated factors among patients admitted to University of Gondar hospital, Northwest Ethiopia: a prospective, observational study

Background Phlebitis, inflammation of tunica intima of venous wall, occurred in 13–56% of hospitalized patients. It is characterized by pain, erythema, swelling, palpable venous cord, and pussy discharge at catheter site. Cannula-related blood stream infection (CRBSI) is recognized complication of phlebitis. Adverse outcomes of phlebitis embrace patient discomfort, longer hospital stay and higher health care cost. This study aimed to determine the incidence and associated factors of peripheral vein phlebitis among hospitalized patients. Methods A hospital-based prospective, observational study was conducted between April 1 and August 31, 2020 at University of Gondar hospital, Northwest Ethiopia. A consecutive sampling method was used to recruit 384 patients. Patients were interviewed to obtain socio-demographic data. Relevant medical history and laboratory parameters were obtained from patients’ records. Presence and severity of phlebitis was identified by Jackson’s Visual Infusion Phlebitis (VIP) Scoring System. The Data were entered into EPI Info version 4.4.1 and transported to SPSS version 20 for analysis. Logistic regression analysis was used to identify associated factors with occurrence of phlebitis. P-value < 0.05 was used to declare significant association. Result A total of 384 study subjects were included in the study. The mean age of study subjects was 46 years, with a range of 19 to 96 years. The incidence of phlebitis was 70% among study subjects. Mid-stage (grade 3) and advanced-stage (grade 4) phlebitis were noticed in 136/268 (51%) and 89/268 (33%) respectively. Odds of developing phlebitis were twofold higher in patients with catheter-in situ > 96 h (AOR = 2.261, 95% CI 1.087–4.702, P-value = 0.029) as compared to those with catheter dwell time < 72 h. Female patients were 70% (AOR = 0.293, 95% CI 0.031–0.626, P-value = 0.002) lower than male patients with risk of developing phlebitis. Patients who use infusates were 53% (AOR = 0.472, 95% CI 0.280–0.796, P-value = 0.005) less likely to develop phlebitis as compared to those who didn’t use infusates. Conclusion The cannula must be reviewed on daily basis, and it should be removed if it stayed later than 96 h.

This study was the first of its kind in Ethiopia to determine the incidence and associated factors of peripheral vein phlebitis among adult hospitalized patients.

Study design and setting
A hospital-based prospective, observational study was conducted between April 1 and August 31, 2020 at emergency unit, medical and surgical wards of University of Gondar hospital. Both wards had a capacity of 92 beds. The hospital is located in Northwest Ethiopia, which is 750 km away from the capital, Addis Ababa. The hospital had a catchment population of 5 million people.

Study subjects and variables Study subjects
All patients admitted to emergency unit, medical and surgical wards during the study period were considered as study population. Patients older than 18 years old, who were admitted to emergency unit, medical and surgical wards and who were on peripheral intravenous catheter, were included in the study. Patients with history of allergy to intravenous cannula, or those unable to give consent were excluded from the study.
Independent variables: (1) Socio-demographic characteristics include age, gender, occupation, marital status, educational level, income level, residence and religion (2) Clinical characteristics include admission diagnosis, duration of hospital stay, cannula insertion site, catheter size (gauge), catheter dwell time, intravenous drugs use, infusates use, blood products use, performance level, and co-existing comorbidities.

Sample size and sampling procedure
The sample size was calculated using single population proportion formula with the assumption of 95% confidence level, 5% margin of error, and taking 50% estimated proportion of phlebitis. Consecutive sampling method was used to recruit 384 study subjects.

Data collection instrument and procedures
Data were collected through an investigator administered pre-designed questionnaire. Patients were interviewed to obtain socio-demographic data. Relevant medical history and laboratory parameters were obtained from patients' records. Three investigators (one medical doctor, two clinical nurses) participated in the data collection process and follow-up of patients on indwelling catheter. Insertion of a catheter was performed by clinical nurses. Hygienic hand-rub with 70% alcohol was done after hand washing. Patient's skin was disinfected using 1% iodine solution and 70% alcohol. Using clean gloves, a catheter was inserted into a peripheral vein of a patient. The catheter was fixed to the patient's skin with protective dressing and plaster. Patients on indwelling catheter were followed daily by investigators from insertion to developing phlebitis or catheter removal. Those who developed phlebitis were graded based on Jackson's Visual Infusion Phlebitis (VIP) Scoring System [17] and were taken care of as per the recommendations of Infusion Therapy Standard of Practice [2].

Data analysis
Data were entered into EPI Info version 4.4.1 and transported to SPSS version 20 for analysis.
Patient characteristics were reported as counts (percentages) for categorical variables, and mean with standard deviation for continuous variables. Bivariable and multi-variable logistic regression models were constructed to identify independently associated factors with occurrence of phlebitis. Those variables with a P-value < 0.25 in the bi-variable analysis were exported to multi-variable analysis to control the possible effect of confounders. Crude odds ratio (COR) and adjusted odds ratio (AOR) were reported. Pvalue < 0.05 was used to declare significant association.

Ethical considerations
The research protocol complied with Declaration of Helsinki, and was approved by local ethics committee (06/09/2012; IRB No. 09/26/629/12). Study subjects were recruited only after informed written consent was obtained. All data obtained were treated confidentially.

Definition of terms Phlebitis
Occurrence of at least one inflammatory sign or symptom related to the catheter insertion, comprising persistent pain (duration longer than 2 h after end of infusion) and/or erythema and/or swelling (induration) and/or palpable cord and/or pussy discharge at intravenous site and/or pyrexia [17].

Grading of phlebitis
Grade 1 phlebitis: one of the following is evident: Pain near IV site or erythema near IV site; Grade 2 phlebitis (early stage of phlebitis): Two of the following are evident: Pain at IV site, erythema or swelling; Grade 3 phlebitis (mid stage of phlebitis): All of the following signs are evident: Pain along path of cannula, erythema and induration; Grade 4 phlebitis (advanced stage of phlebitis or early stage of thrombophlebitis): All of the following signs are evident and extensive: Pain along path of cannula, erythema, induration and palpable venous cord; Grade 5 phlebitis (Advanced stage of thrombophlebitis): All of the following signs are evident and extensive: Pain along path of cannula, erythema, induration, palpable venous cord, and visible pussy discharge at IV site or pyrexia [17].

Socio-demographic characteristics of study participants
A total of 384 participants were included in the study. The mean age of study subjects was 46 years, with a range of 19 to 96 years. More than half (52%) of them were males and were rural dwellers (53%). Majority (89%) of respondents were Christian by religion. Fewer than half (43%) of study subjects attended formal education (Table 1).

Clinical characteristics of study participants
Two-thirds (63%) of the patients were semi-ambulatory. Majority of patients were hospitalized with lung (25%), heart (18%) and CNS (17%) diseases. Two-third (63%) of patients presumed to have bacterial infections. Fewer than 10% of patients each were diagnosed to have diabetes, CKD, HIV/AIDS, and malignancy as comorbidities. Indications for PIVC insertion were administration of intravenous drugs (73%), infusates (65%), and blood products (14%). Half (53%) of the catheters were inserted in emergency situations. Forearm was used as catheter placement in half (52%) of patients. 20 G sized cannula was used in most (81%) patients. Twothird (66%) of patients had PIVC in-situ for 96 h or less (Tables 2 and 3).

Incidence and grades of phlebitis
The incidence of phlebitis was 70% (268/384) among study subjects. Among those who developed phlebitis, mid-stage (grade 3) and advanced-stage (grade 4) phlebitis were noticed in 136/268 (51%) and 89/268 (33%)   Table 4). Place of procedure done, catheter site placement, catheter size (gauge), use of blood products, concomitant bacterial infections, and co-existing comorbidities such as diabetes, CKD and malignancy were not found to be significantly associated with occurrence of phlebitis in bi-variable analysis (P-value > 0.25).

Discussion
The incidence of phlebitis was 70% with use of peripheral intra venous catheters. It was higher than phlebitis rate reported in other studies, which ranged from 13-56% [4-6, 9-13, 15, 16]. The incidence of phlebitis was much higher than acceptable phlebitis rate recommended by Infusion Nurses Society (INS), which should be 5% or less [2]. High grade phlebitis (grade 3 and 4) accounted the majority (84%) based on Jackson's Visual Infusion Phlebitis Scoring System, which required treatment and cannula re-site. Most indwelling catheters were detected after developing advanced stage of phlebitis, which might refer to ineffective preventive measures and poor catheter management. Phlebitis significantly occurred among those with catheter dwell time > 96 h as compared to catheter-in situ < 72 h (AOR = 2.261, 95% CI 1.087-4.702, P-value = 0.029). This finding was consistent with other studies [4, 6, 8-10, 13, 15]. Prolonged catheter dwell time predisposes for continued trauma by the catheter itself, longer contact to irritant drugs and infusates, and higher chance of exposure to bacterial colonization and infections. CDC guideline (2011) recommended routine replacement of PIVC no later than 96 h. There was lower rate of phlebitis among patients who used infusates (AOR = 0.472, 95% CI 0.280-0.796, P-value = 0.005) as compared to those who didn't use infusates. This finding could be explained by frequent use of non-risky, isotonic solutions as infusates. Isotonic infusate has equal osmolality to that of blood, so then it might reduce phlebitis rate [8][9][10]15]. Lower rate of phlebitis occurred among females (AOR = 0.293, 95% CI 0.031-0.626, P-value = 0.002). It was incongruent with reports from other studies, in which females outnumbered males in incidence of phlebitis [4,7,12,16]. There was no sound explanation for gender-based differences regarding incidence of phlebitis.

Limitation
Selection bias couldn't be avoided as consecutive sampling method was used to recruit study subjects.