Objectives: To describe some of factors related to nosocomial infection in Intensive Care Unit of National Hospital for Tropical Diseases (2011 - 2012). Subjects and methods: A prospective study evaluating some of factors related to nosocomial infection in Intensive Care Unit from Jan 2011 to Dec 2012 on 682 inpatients.
Trang 1SOME RELATED FACTORS TO NOSOCOMIAL INFECTION
IN THE INTENSIVE CARE UNIT OF NATIONAL HOSPITAL FOR TROPICAL DISEASES
Doan Quang Ha 1 ; Nguyen Van Kinh 1
Nguyen Vu Trung 1 ; Nguyen Van Chuyen 2
SUMMARY
Objectives: To describe some of factors related to nosocomial infection in Intensive Care
Unit of National Hospital for Tropical Diseases (2011 - 2012) Subjects and methods: A prospective
study evaluating some of factors related to nosocomial infection in Intensive Care Unit from Jan
2011 to Dec 2012 on 682 inpatients Results: Invasive interventions were associated with nosocomial
infection, including: gastrostomy, mechanical ventilation, central venous catheterization,
angioplasty and catheterization There is a relation between duration of therapy and the risk of
nosocomial infection Patients hospitalized for 10 - 15 days had the highest risk of
hospital-acquired infection Risk factors for hospital pneumonia: Intubation for more than 5 days; risk
factors for hospital sepsis: central venous catheterization more than 3 days; risk factors for
urinary tract infection: urinary catheter more than 3 days Conclusions: Medical invasive
interventions and duration of therapy are the main factors influencing nosocomial infection in the
Intensive Care Unit of National Hospital for Tropical Diseases
* Keywords: Nosocomial infection; Related factors
INTRODUCTION
Nosocomial infections (NI) is a
bacterial infection that patients suffer
during hospitalization, which is one of the
main causes of morbidity and mortality for
patients in hospitals around the world [2]
NI is usually caused by antibiotic-resistant
bacteria, which makes it difficult to treat,
prolong hospital stay, increase the risk of
death and the cost of treatment
In the European Union, the annual
mortality rate from infections with resistant
strains is 25,000 and in the United States
over 63,000 According to a survey conducted
by the WHO in 55 hospitals in 14 countries, the average NI rate was 8.7% wheres West Mediterranean: 11.8%; Southeast Asia: 10.0%; Europe: 7.7% and Western Pacific 9.0%, among of which pneumonia accounts for the highest rate, followed by septicemia, surgical site infections and urinary tract infections
These infections account for 80% of all cases of NI and causes huge economic losses including increased cost of treatment and reduced labor Each year,
it costs of the US 5.7 billion for patient care, much higher than the cost of influenza prevention [3]
1 National Hospital for Tropical Diseases
2 Vietnam Military Medical University
Corresponding author: Doan Quang Ha (ha_doan@nhtd.vn)
Date received: 10/10/2018
Date accepted: 30/11/2018
Trang 2Nosocomial infection at intensive care
unit (ICU) is twice or 3 times higher than
other departments in the hospital [4]
In Vietnam, there is no research on NI in
ICU wards of NI, yet adequate analysis of
risk factors related to NI has been made
to provide appropriate intervention
This study aims: To describe some of
the risk factors associated with NI in the
ICU of the National Hospital for Tropical
Diseases (2011 - 2012), as a scientific basis
for interventions
SUBJECTS AND METHODS
1 Subjects, location, time
* Subjects:
Patients who were treated in ICU of
National Hospital for Tropical Diseases
from 01 - 1 - 2011 to 31 - 12 - 2012
* Location: ICU of National Hospital for
Tropical Diseases
* Time: January 1st 2011 - December
31st 2012
2 Methods
* Research design:
A prospective, case-control analysis of
relacted factors of NI in ICU, the National
Hospital for Tropical Diseases
* Sample size and sampling method:
- Sample size:
Total sample size of patients with NI in
ICU who had treatment in period from
January 1, 2011 to December 31, 2012
- Sampling method:
Select randomly, continuous pattern All patients eligible for ICU admission will
be selected
- Inclusion criteria:
Patients were treated in the ICU at least than 48 hours
- Exclusion criteria:
Patients who had NI before admission to the ICU or have manifestations of NI within the first 48 hours since admission
to the ICU
* Research variables and methods of data collection:
- Research variables:
+ Major variables:
Case definition: The NI standard is based on the WHO 2002 standard [1] Time is calculated from 48 hours after entering Emergency-Intensive Care Department
to 48 hours after leaving Emergency-Intensive Care Department
Secondary variables:
Duration of treatment at ICU: from hospitalization to the discharge of Emergency- Intensive Care Department
The entire duration of treatment: the time patient were treated in hospital
- Independent variables:
+ Invasive intervention:
Intubation & mechanical ventilation, nasal continuous positive airway pressure, peripheral venous catheterization, central venous catheterization, urinary catheterization,
Trang 3gastroenteric tube feeding Other interventions:
drainage of pleural cavity, peritoneal cavity,
aerosol, hemodialysis…
Drug treatment:
Antibiotics: When antibiotics are used,
there is evidence of bacterial infection in
patients
Other drugs: Corticosteroids, H2 blockers,
vasopressors and inotropes (dopamine
and dobutamine), macromolecules, muscle
relaxants (diazepam and phenobarbital)
are included when administered to patients
for a minimum of 24 hours
Blood transfusion: When a patient
receives blood transfusions and blood
products
Parenteral nutrition: When the patient
is fed with a solution containing protein or
fat for at least 24 hours
Time to place the instruments, or use
the drug before NI: From the time of
intervention until the detection of NI
If the patient does not have NI, it will be
calculated from the time of placing or
using the drug until the end of the
intervention or when leaving the ICU
* Data collection:
- Initial evaluation of the patient:
Patients eligible for the study were
examined, performed diagnostic tests and
assessed their status, recorded gender,
age, comorbidity, if any, date of entry The
initial information will be filled in the form
- Patient monitoring and evaluation:
All patients were taken care, monitored
and treated according to the hospital regimen
in accordance with the condition and under the same control conditions of the NI
Patient interventions and treatments were documented on the date and time of use Monitor and evaluate the NI related signs of each position
- Urinary catheterization: Test urine every 72 hours until urinary catheters were removed, when there is urine nitrite (+) and/or white blood cell (+), it was suspected of urinary tract infection
- Endotracheal intubation: When there
is clinical febrile or changes in sputum or crackles lung sound, chest X-ray is indicated
- Intravenous catheter insertion: When there is a change in the injection site right away, or manifestation of the infectious disease syndrome, carry out tests to identify infections
- Tests to identify cases:
Blood culture is done when the patient shows signs of infection:
+ There are 2 of the following 4 criteria: fever > 38.50C; rapid pulse; rapid breathing; neutropenia increases or decreases with age or rate neutrophil > 10%
+ Evidence of infection or suspected
by examination, test Blood is collected from peripheral blood at a volume of
1 - 2 mL with sterile syringe, inserted into blood culture bottle BactecPeds plus/F and cultured with automatic BACTEC 9420
- Get a chest X-ray, obtain sputum by nasotracheal aspiration method (NTA) or use the endotracheal tube if the patient is
Trang 4intubated, when the patient have such
symptoms as: cough, increased sputum,
purulent sputum, hear crackles lung sound
Sputum suction device is a specialized
sterile one designed specifically for the nose
and trachea or suctioned through the
endotracheal tube Evaluate the quality of the
specimen based on the Bartlett standard
- Urine culture was performed on the
3rd day after urinary catheterization and
repeated when having symptoms: Dysuria,
urinary retention, pain in pubic bone, or
cloudy urine; if urinary catheters were not
available, urine culture should be performed
when there are symptoms: dysuria, urinary
retention, pain in pubic bone, or leucocyte
ornitrite in the urinalysis Urine was
obtained from a sterile syringe from the
collecting tube of the urine vesicle if the
urinary catheter was placed A specimen
was considered positive when there is at
least 105 CFU/mm3
- Culture pus from wounds and secretions
from drainage pipes to find pathogens
Pus, fluid, and wound secretions are
removed by using sterile syringes or
sterile sticks and then placed in sterile
vials and sent to the laboratory The
specimens are then cultured to find the
bacteria on aerobic and fungal environments
if suspected of fungus
Interpretation of results: If an agent is
isolated, it wil be considered as the
cause of the disease In the case of
specimens cultured from two or more
agents, the dominant agent will be
considerd as the cause of the infection
In cases where the results are negative but there are still doubts, they might be cultured again
- Case definition and questionnaire completion:
Patients were monitored for 48 hours after leaving the ICU, if there were NI symptoms during this period, it was also referred to as NI in the ICU Case definition was in accordance with the WHO 2002 standard The patient's final result was evaluated until discharge, total time in the ICU, the length of hospital stay and the cost of treatment were recorded
Complete the questionnaire when the patient left the ICU within 48 hours Check the questionnaire, compared with the medical record when discharged
* Data analysis:
Data were processed statistically by SPSS 22.0 software
Comparison and correlation: Comparing the exposure factors in two groups with NI and non-NI: Using t-test when comparing two means, test χ2 compares two ratios and Fisher's test compares two ratios have small samples; considered significance with p < 0.05 for two-sided
Determination of risk factors: Risk factors were analyzed by logistic regression Significant risk factors in logistic regression analysis will have a corresponding regression coefficient β
Trang 5RESULTS
1 Distribution of NI
Table 1: Relationship between invasive intervention and the NI
Non-NI (n = 383) NI (n = 299) Invasive intervention
p-values
Endotracheal intubation or ventilation 45 11.8 158 52.8 < 0.001
Intravenous transfusion
01 line intravenous transfusion
02 lines intravenous transfusion
03 lines intravenous transfusion
174
170
39
45.4 44.4 10.2
134
134
31
44.8 44.8 10.4
0.987
Intravenous invasive interventions were associated with the NI, including gastric ulcer, endotracheal intubation - ventilation, central venous catheterization, intravenous exposures, angioplasty and urinary catheter
Table 2: Comparison of instrumental use index between the two groups with NI and
non-NI by type of invasive intervention
Non-NI (n = 383) NI (n = 299) Invasive intervention
Time (n = 2,843) IUI
Time (n = 3,384) IUI
p
Central venous catheterization 49 0.017 1.187 0.306 < 0.001
Trang 6Urinary sonde 350 0.123 299 0.091 < 0.001
(Indicators use interventions [IUI)] = Instrument insertion time [INT]/total time of therapy)
Figure 1: Correlation between instrument insertion time and IUI in group of NI
0.229
0.082
0.017
0.123
0
100
200
300
400
500
600
700
Gas
tric
onde
Endo
trac
heal
Intu
batio n
Cent
l ven
ous
cath
eri
.
In
aven
ous
expo
sure s
Angi
opla yc
hete rizat
ion
Urin
ary
sond e
Pleu
ral e ffusi on
Perit
onea
l dra
inag e
0 0.05 0.1 0.15 0.2
0.25
Figure 2: Correlation between instrument insertion time and
IUI in group of non-NI
The mean of IUI in NI patients was higher than in non-NI patients (p < 0.001)
The results of figures 1 and 2 showed that there was a correlation between
instrument insertion time and IUI Long instrument placement increases the IUI,
also increases the risk of NI
Trang 720
40
60
80
Hospitallized time (days)
Figure 3: Correlation between the number of NI cases and
the number of days treated at the ICU
The number of NI cases increased gradually in the treatment group after 5 days
The number of NI was the highest in patients with 10 - 15 days
2 The results of analysis of some risk factors related to NI
Table 3: Relationship between some risk factors of hospital pneumonia
Hospital pneumonia Invasie intervention
Total
Yes n = 135 Non n = 547
OR (95%CI) p
Endotracheal intubation 203 (29.8) 68 (33.5) 135 (66.5) 3.0 (2.5 - 3.6) 0.001
Endotracheal intubation
> 5 days 181 (26.5) 46 (25.4) 135 (74.6) 3,9 (3.1 - 5.1) 0.001
Block H 2 216 (31.7) 49 (22.7) 167 (77.3) 1.3 (0.9 - 1.9) 0.215
Gastric sonde 305 (44.7) 65 (21.3) 240 (78.7) 1.2 (0.8 - 1.7) 0.386
Sedative 198 (29.0) 45 (22.7) 153 (77.3) 1.3 (0.9 - 1.9) 0.244
Muscle relaxant 107 (15.7) 26 (24.3) 81 (75.7) 1,4 (0.8 - 2.2) 0.234
Multivariate analysis revealed that the risk factors for hospital pneumonia were
intubation with OR 3.0 (2.5 - 3.6), duration of intubation with OR 3.9 (3.1 - 5.1) The use
of sedative, H2 blockers, peptic ulcer and muscle relaxant was not a risk factor for
multivariate analysis (p > 0.05)
Trang 8Table 4: Multivariate analysis of risk factors for sepsis
Sepsis
Invasive intervention Total
Yes, n = 75 (%) No, n = 607 (%)
Central venous
catheterization 133 (19.5) 75 (56.4) 58 (43.6) 2.3 (1.9 - 2.8) 0.001
Central venous
catheterization > 3 days 132 (19.4) 75 (56.8) 57 (43.2) 2,3 (1.9 - 2.8) 0.001
No of intravenous
transfusion ≥ 3 days 70 (10.3) 12 (17.1) 58 (82.9) 1.8 (0.9 - 3.5) 0.104
Intravenous nutrition 155 (22.7) 17 (11.0) 138 (89.0) 1.0 (0.6 - 1.8) 1.00
Blood transfusion 217 (31.8) 26 (12.0) 191 (88.0) 1,2 (0.7 - 1.9) 0.600
By multivariate analysis, the risk factors for sepsis were placement of central venous catheterization with OR 2.3 (1.9 - 2.8); keep venous catheterization more
3 days with OR 2.3 (1.9 - 2.8); 100% of all cases of intravenous exposures were related to sepsis, transfusion 3 days, intravenous nutrition, blood transfusion was not a risk factor (p > 0.05)
Table 5: Single-variable analysis of risk factors for urinary tract infections
Urinary tract infections Invasive intervention
Yes, n = 16 (%) No, n = 666 (%)
Urinary catheter 16 (7.5) 196 (92.5) 1.08 (1.04 - 1.12) 0.001
Keep urinary catheter > 3 days 16 (7.5) 196 (92.5) 1.08 (1.04 - 1.12) 0.001
Single-variable analysis revealed that risk factors for urinary tract infections were urinary sonde OR = 1.08 (1.04 - 1.12) and time to urinary sonde > 3 days, OR 1.08 (1.04 - 1.12)
Table 6: Multivariate analysis of risk factors for infection of intravenous transfusion site
Infection of intravenous transfusion site Invasive interventions
Yes, n = 63 (%) No, n = 619 (%)
OR (95%CI) p
Central venous catheterization (b) 36 (26.3) 97 (73.7) 7.2 (4.2 - 12.4) 0.001
Number of intravenous transfusion
Blood circulation drugs 13 (7.8) 153 (92.2) 0,8 (0.4 - 1.5) 0.540
(a: Venous; b: Central venous)
Risk factors of infection for venous catheterization sites were central venous catheterization with OR 7.2 (4.2 - 12.4) Intravenous and blood circulation drugs were not risk factors for infection of catheterization sites
Trang 9DISCUSSION
Nosocominal infections in ICU are often
the highest in most hospitals [3]
This situation is explained by the fact
that in the ICU area more and more
patients are at high risk of developing
high levels of NI, such as severe disease,
requiring multiple invasive procedures
Therefore, prevention of the NI is very
important in ICU ward For effective
prevention, it is important to identify risk
factors, on the basis of which measures to
prevent and control NI well suited
Multivariate analysis results of each
type of NI indicate that the risk factor for
pneumonia is intubation with endotracheal
time more than 5 days; the risk factor for
hospital sepsis is intravenous central venous
catheterization, maintenance of intravenous
central venous catheterization more than
3 days and intravenous exposure; the risk
factors for urinary tract infection are urinary
catheterization and urinary retention time
more than 3 days
Some domestic and foreign authors’
findings: Nguyen Viet Hung et al (2012)
reported a relationship between NI and
urinary done (OR = 3.5, p < 0.01), respiratory
ventilation (OR = 2.9, p < 0.05) [4]
This result was consistent with the
results from the US hospital surveillance
statistics of 83% of bacterial pneumonia
associated with artificial ventilation, 97%
of urinary tract infections occured in
patients with urinary catheterization and
87% sepsis occurred in patients receiving
central venous catheters [4]
At the ICU of National Hospital for
Tropical Diseases, most patients suffer
from serious diseases and have undergone
many invasive procedures such as respiratory ventilation, intravenous central venous catheter, urethral catheter These results show that there needs to focus resources facilities on control of NI in the ICU area
of the hospital, particularly the need for increased sterilization practice in the care
of patients with invasive interventions involving the airway, blood vessels and urinary tract
CONCLUSSION
Invasive interventions were associated with NI including intubation, respiratory ventilation, central venous catheterization, arterial catheterization and urinary sonde There was a correlation between the duration
of treatment and the risk of NI Patients hospitalized for 10 - 15 days have a higher risk of NI
Risk factors for hospital pneumonia was endotracheal intubation more than
5 days; the risk factors for hospital sepsis were central venous catheterization for
3 days and intravenous exposures; the risk factor for urinary tract infection was the duration of the urinary catheter more than 3 days
REFERENCES
1 Nguyen Viet Hung et al Rate of related
factors and hospital infectious agents in Bachmai Hospital Journal of Practic Medicine 2012, 869 (5)
2 Ministry of Health Guidelines for Hospital
Infection Control Medical Publishing House 2013
3 World Health Organization Report on
burden of endemic health care - associated infection worldwide 2011
4 World Health Organization Prevention
of hospital - acquired infections Practical Guide WHO Press 2002.