Evaluation of healthcare associated infections at pediatric critical care units

Objective: Health-care associated infection (HAI) constitutes a major health care problem resulting in prolonged hospital stay with increased medical costs. The burden is much greater by accompanying risk factors among intensive care admissions. The incidence is reported 30% of all ICU admissions in developed countries; however the estimated rates are clearly higher in developing countries³.  

In order to prevent HAIs, the health-care facilities should determine their own risk factors, analyse the microorganisms isolated from the body fluids and provide the necessary precautions accordingly⁵. Despite all the efforts and the advances at preventive protocols, the HAI burden still exits. 

The pediatric intensive care unit (PICU) of Sivas Cumhuriyet University Hospital is a tertiary critical care unit serving to a broad range of population under 18 years with highly advanced technology within a considerably populated territory. The demographic profiles of the admissions account a wide range of childhood sicknesses from trauma to neurological disorders. The aim of this retrospective study was to examine the microorganism profiles isolated from the body fluids (blood, urine, tracheal aspirates, wound cultures, spinal fluid) of all PICU admissions during the past five years. Hence we decided to obtain our local surveillance data, deploy the necessary precautions to decline HAIs and administer the appropriate antimicrobial therapy accordingly.

Method: In this retrospective descriptive study, we searched the medical records of all PICU admissions between January 2014 and December 2018.  Children with i) PICU admission lasting over 48 hours, ii) culture positiviy at body fluids, iii) presenting clinical signs of infection were enrolled in the study. Patient demographics, initial complaints, admission diagnosis, the underlying chronical  conditions, the source of PICU admission (admission from an indoor clinic, emergency service or an outdoor clinic) and previous hospitalizations were all recorded. We recalled HAI subgroups according to the definitions of centers for disease control and prevention (CDC)⁶ such as: ventilator-associated pneumonia (VAP),  blood stream infection (BSI), central line-associated bloodstream infections (CLABSIs), catheter-associated urinary tract infections (CAUTI) and surgical site infections (SSI).
SPSS-23 (Statistical Package for Social Sciences for Windows 23) was used for statics of the study. Descriptive analyses were expressed as percentages, mean±standart deviation (SD), median with minimum and maximum values. Chi square and Fischer exact test were used for comparison of categorical variables. Normal and non-normal distributions of continous variables were assessed by Student’s t-test, Mann Whitney U test and Wilcoxon rank sum test. P-value < 0.05 was considered significant.

Results: Investigation of 1566 PICU admissions between the periods January 2014 and December 2018, presented 56 children with 71 culture positivity at body fluids (infection rate:4.5%). The median age was 15 months (2 months-17 years) and male gender occupied 58.9% of the study population. We observed respiratory distress and acute pneumonia as the major complaint and the diagnosis at admission (48.5% and 35.7% respectively). 76.7% of the children manifested previous hospitalizations. Forty-three children presented an underlying chronical condition; mainly involving the central nervous system. The sources of PICU admission were identified as: first admission from the emergency service (44.6%), an outdoor clinic (28.6%) and an indoor clinic (pediatric ward)  (26.8%).  

In terms of culture positivity, we observed PICU-infections as (in decreasing order): VAP (26/71, 36.6%), BSI (18/71, 25.4%), CAUTI (18/71, 25.4%), SSI (7/71, 9.9%) and CLABSIs  (2/71, 2.8%). Infections with gram-negative bacteria constituted the major infection group (54/71, 77.1%); Acinetobacter baumanii and Klebsiella pneumonia seemed as the most frequent isolated microorganisms (25.3% and 14.1%). Fungi infections incapsulated 12.6% of the infections overall. Amog the thirty (42.2%) antibiotic resistant-culture positivity, carbapenem resistant and ESBL positive bacteria occured as the common strains (21.1% and 12.7% respectively). We observed Carbapenem resistant strains mostly at SSI (5/15, 33.3%), while ESBL positive strains were developed at BSI and CAUTI.

In terms of ventilator-associated events, the mean intubation length was 17.5±5.4 days. Pseudomonas aeruginosa ve Acinetobacter baumanii were the most common bacterias reproduced at tracheal aspirates. For the resistance strains, Colistin–resistant Acinetobacter baumanii demonstrated the most prominent resistant strain at a rate of 50%, followed by Carbapenem-resistant strains (15.4%). Colistin-resistant strains seemed to have an escalating trend especially in 2018, on the contrary the frequency of carbapenem-resistant strains have declined over ther years.
Length of PICU stay and hospitalization were 38.1±27.6 days and 42.2±27.6 days respectively. Twelve children died of infections (21.4%). Age less than five years and higher PRISM-3 scores were associated with mortality (p=0.004 and p<0.001). Those who died had longer intubation, PICU stay and hospitalization periods with significant nasogastric tube insertion rates (in following order, p=0.007, p=0.010, p=0.045, p=0.001).

Conclusions: Health-care associated infections remain to be a major problem all around the world. What we can do to overcome this challenge is, to initiate local survaillance protocols, educate the health-care stuff on hand hygiene, enforce appropriate isolation tactics and practice wise antibotic administration.