| Literature DB >> 34976541 |
Abstract
Introduction Hospital-acquired infections can be associated with an increase in morbidity, length of stay, and cost. Data on this topic are very limited in Mauritius. This study seeks to identify (a) the most prevalent hospital-acquired infection locally, (b) the risk factors for acquiring nosocomial infections, and (c) the mortality rate linked to such infections. Methods This is an observational study that was conducted at a 600-bed hospital in Mauritius by going through the folders of 109 patients who were admitted in different wards. Cox regression was used to carry out the survival analysis. Results Over the past 25 years, the incidence of hospital-acquired infections has increased by two to three times in Mauritius to reach a value of 18 per 100 admitted patients. The most commonly identified nosocomial infection was ventilator-associated pneumonia. The presence of foreign devices increased the risk of acquiring nosocomial infections. The mortality rate from such infections was almost four times higher compared to the mortality rate from patients who did not suffer from these infections; however, after adjustment for potential confounders, this was not statistically significant. The incidence of ventilator-associated pneumonia and central line-associated bloodstream infections was high at 46 per 1,000 ventilator-days and 25 per 1,000 central line days, respectively. Conclusion Infection prevention and control measures should be implemented to curtail the rise of hospital-acquired infections in Mauritius. Such measures should include the use of bundles of care. In addition, periodic surveillance of nosocomial infections needs to be encouraged.Entities:
Keywords: central line-associated bloodstream infections; hospital-acquired infections; nosocomial; surgical site infections; ventilator-associated pneumonia
Year: 2021 PMID: 34976541 PMCID: PMC8713534 DOI: 10.7759/cureus.19962
Source DB: PubMed Journal: Cureus ISSN: 2168-8184
Definitions of site-specific hospital-acquired infections.
CAUTI, catheter-associated urinary tract infections; CLABSI, central line-associated bloodstream infections; CXR, chest X-ray; HAI, hospital-acquired infections; HAP, hospital-acquired pneumonia; PCR, polymerase chain reaction; SSI, surgical site infection; US, ultrasound; VAP, ventilator-associated pneumonia; WBC, white blood cells
| HAI | Timeline | Clinical | Laboratory | Radiological | Microbiological |
| VAP | >48 hours after intubation or <48 hours after extubation | Fever > 38.0°C or < 36°C, new antimicrobial started, hypoxia, septic shock without any other cause | WBC ≤ 4,000/mm3 or WBC ≥ 12,000/mm3 | CXR or CT chest | Endotracheal aspirate culture, pleural fluid culture, urine antigen test, or PCR on respiratory samples |
| CLABSI | Line is present > 48 hours or line is removed < 24 hours ago | If a commensal is grown: fever > 38°C, chills, hypotension | Blood culture | ||
| SSI | D0 to D30 after most surgeries without foreign bodies being present; D0 to D90 if foreign bodies are inserted | Inflammation at surgical site, pus, dehisced wound, localized pain or tenderness, localized swelling, erythema around the site, heat at the site or fever > 38°C | US/ CT/MRI showing infection at surgical site | Pus culture | |
| CAUTI | Foley is present > 48 hours or Foley is removed < 24 hours ago | Fever > 38°C, suprapubic tenderness or costovertebral angle tenderness | Urine culture | ||
| HAP | > 48 hours after admission | Fever > 38.0°C, confused if ≥ 70 years old, cough, dyspnea, bronchial breathing, or hypoxia | WBC ≤ 4,000/mm3 or WBC ≥ 12,000/mm3 | CXR or CT chest | Sputum culture, urine antigen test, or PCR on respiratory samples |
Figure 1Flow diagram illustrating how patients were selected in the study.
Main characteristics of the controls and cases.
CI, confidence interval; HAI, hospital-acquired infections; HCF, healthcare facility; IVDU, intravenous drug user; OR, odds ratio; SOFA, sequential organ failure assessment
| Variable | Controls (n = 52) | Cases (n = 16) | OR (95% CI) | p-Value |
| Males | 32 (62%) | 7 (44%) | 0.49 (0.16–1.5) | 0.21 |
| Age ≥ 60 years | 27 (52%) | 4 (25%) | 0.31 (0.09–1.1) | 0.05 |
| SOFA > 2 | 10 (19%) | 12 (75%) | 13 (3.3–47) | 1.8E-4 |
| Central venous line present | 8 (15%) | 9 (56%) | 7.1 (2.0–24) | 0.002 |
| Hemodialysis line present on admission | 2 (3.8%) | 1 (6.3%) | 1.7 (0.14–20) | 0.69 |
| Foley catheter present | 20 (38%) | 11 (69%) | 3.5 (1.1–12) | 0.04 |
| On ventilator | 4 (7.7%) | 6 (38%) | 7.2 (1.7–30) | 0.007 |
| Surgery done during admission | 18 (35%) | 10 (63%) | 3.1 (1.0 - 10) | 0.05 |
| Diabetes mellitus | 10 (19%) | 5 (31%) | 1.9 (0.54–6.7) | 0.32 |
| Cerebrovascular accident | 7 (13%) | 1 (6.3%) | 0.43 (0.05–3.8) | 0.45 |
| Dialyzed at baseline | 1 (1.9%) | 1 (6.3%) | 3.4 (0.20–58) | 0.40 |
| Asthma | 2 (3.8%) | 0 (0%) | - | 1.0 |
| Cirrhosis | 1 (1.9%) | 0 (0%) | - | 1.0 |
| Congestive heart failure | 1 (1.9%) | 1 (6.3%) | 3.4 (0.20–58) | 0.40 |
| Ischemic heart disease | 4 (7.7%) | 2 (13%) | 1.7 (0.28––10) | 0.56 |
| Peripheral vascular disease | 0 (0%) | 0 (0%) | - | 1.0 |
| Cancer | 3 (5.8%) | 1 (6.3%) | 1.1 (0.11 - 11) | 0.94 |
| Admitted in an HCF in the last 3 months | 16 (31%) | 5 (31%) | 1.0 (0.31–3.4) | 0.97 |
| Decubitus ulcers | 0 (0%) | 2 (13%) | - | 1.0 |
| On steroids | 2 (3.8%) | 4 (25%) | 8.3 (1.4–51) | 0.02 |
| On chemotherapy in the last 6 months | 2 (3.8%) | 1 (6.3%) | 1.7 (0.14 - 20) | 0.69 |
| HIV status | 4 (7.7%) | 1 (6.3%) | 0.80 (0.08–7.7) | 0.85 |
| Malnourished | 1 (1.9%) | 0 (0%) | - | 1.0 |
| IVDU | 5 (9.6%) | 1 (6.3%) | 0.63 (0.07–5.8) | 0.68 |
| On appropriate empiric antibiotics initially | 15 (29%) | 1 (6.3%) | 0.16 (0.02–1.4) | 0.09 |
| Inotropes started | 1 (1.9%) | 3 (19%) | 12 (1.1–120) | 0.04 |
| Started dialysis after onset of HAI | 1 (1.9%) | 1 (6.3%) | 3.4 (0.20–58) | 0.40 |
| Mean length of stay (days) | 21 | 53 | - | 2.0E-7 |
| Deaths | 7 (13%) | 8 (50%) | 6.4 (1.8 - 23) | 0.004 |
Figure 2The Kaplan-Meier curve demonstrating the survival of patients with and without hospital-acquired infections.
Figure 3Pie chart classifying the frequency of each HAI that was identified in the study. VAP, CLABSI, and SSI were the most common types of HAIs, while primary bloodstream infections and vascular site infections were the rarest.
CLABSI, central line-associated bloodstream infections; HAI, hospital-acquired infections; SSI, surgical site infection; VAP, ventilator-associated pneumonia
Figure 4The Kaplan-Meier curve illustrating the risk of developing VAP after being intubated. By 18 days, only 17% of intubated patients did not develop a VAP yet.
VAP, ventilator-associated pneumonia
Definitions of hospital-acquired infections in adults.
CAUTI, catheter-associated urinary tract infections; CLABSI, central line-associated bloodstream infections; CXR, chest X-ray; DOE, date of event; DOD, date of diagnosis; HAI, hospital-acquired infections; HAP, hospital-acquired pneumonia; PCR, polymerase chain reaction; PEEP, positive end-expiratory pressure; SSI, surgical site infection; VAP, ventilator-associated pneumonia; WBC, white blood cell
| Terms | Definitions |
| Contaminants, colonizers, or commensals | Coagulase-negative staphylococcus, diphtheroids, |
| For infections that require positive blood cultures for their diagnoses, the presence of | |
| DOE | The date when the first element used to meet the infection criteria occurs. |
| Infection window period | All the criteria for the infection must be met within the 7-day Infection Window Period (3 days before the date of the first diagnostic test (DOD), on the DOD or 3 days after the DOD). |
| A diagnostic test is a laboratory, radiological, or microbiological test that is part of the list of criteria used for the diagnosis of the specific hospital-acquired infection. | |
| The infection window period cannot start at a time when the patient was not at risk for the infection (e.g., ≤ 48 hours after intubation). | |
| Reactivation | Reactivation of latent disease such as tuberculosis is not considered a hospital-acquired infection. |
| Repeat infection timeframe | A repeat event within 14 days is considered as persistence or relapse of the same infection and is not counted twice. |
| However, an exception is made if both of the following are present: the patient’s diagnostic test is positive for a new organism which is neither a contaminant nor a colonizer AND there is at least one new infection criterion that is met which was not present in the last 48 hours (e.g., for a diagnosis of pneumonia, the patient develops new-onset hypoxia which was absent previously). Under such circumstances, a new event is considered to have occurred. | |
| Incidence | Formulae |
| Incidence risk of HAI | No. of patients with at least one new diagnosis of HAI / No. of patients who could get an HAI * 100 |
| No. of patients who could get an HAI = no. of patients admitted for > 48 hours to the hospital and no. of patients who had surgery in the first 48 hours (if any). | |
| For all calculations of incidence risks, readmissions of the same patients are ignored. | |
| Incidence risk of HAP | No. of patients with at least one new HAP diagnosis / No. of patients admitted to the hospital for more than 48 hours * 100 |
| Incidence risk of SSI | No. of patients with at least one new SSI diagnosis / No. of patients who underwent surgery * 100 |
| Incidence risk of VAP | No. of patients with at least one new VAP diagnosis / No. of patients intubated for more than 48 hours * 100 |
| Incidence rate by device-days of VAP | No. of VAP events / No. of ventilator days * 1,000 |
| No. of ventilator days includes the first 48 hours of ventilation. | |
| Incidence risk of CLABSI | No. of patients with at least one new CLABSI / No. of patients with one or more central lines inserted for more than 48 hours * 100 |
| Incidence rate by device-days of CLABSI | No. of CLABSI events / No. of central line days * 1,000 |
| No. of central line days includes the first 48 hours after insertion of the line. | |
| Incidence risk of CAUTI | No. of patients with at least one new episode of CAUTI in that admission / No. of patients with a urinary catheter inserted for more than 48 hours * 100 |
| Incidence rate by device-days of CAUTI | No. of CAUTI events / No. of urinary catheter days * 1,000 |
| No. of urinary catheter days includes the first 48 hours after insertion of the Foley. | |
| HAI | Definition |
| HAP | DOE is > 48 hours after admission. PLUS |
| One chest X-ray or chest CT is consistent with pneumonia. If a chest X-ray or chest CT is not done, all of the following should be present: a new antibiotic is started for ≥ 4 days AND no other source of infection is found AND a third criterion from the list marked with a asterisk (*) below is observed. PLUS | |
| At least one of the following: fever (> 38.0°C / 100.4°F), leukopenia (≤ 4,000 WBC/mm3) or leukocytosis (≥ 12,000 WBC/mm3), altered mental status with no other cause in ≥ 70 years old. PLUS | |
| At least two of the following: new onset of purulent sputum, or change in character of sputum, or increased respiratory secretions, or increased suctioning requirements; new onset or worsening cough, dyspnea, or tachypnea; rales or bronchial breath sounds; worsening gas exchange (e.g., oxygen desaturation), O2 requirement, or increased ventilation demand - defined as PaO2/FiO2 < 240, SpO2 < 94% on room air or need for supplemental oxygen; positive sputum culture (or other respiratory sample) or pleural fluid culture with an organism other than a contaminant or colonizer; positive urine antigen test for Legionella sp. or Streptococcus pneumoniae; positive PCR test on sputum (or other respiratory sample), throat swab, or nasopharyngeal swab for an organism that is not a contaminant nor a colonizer.* | |
| Note that patients who meet criteria for ventilator-associated pneumonia (see below) are considered to have HAP too. | |
| SSI | Symptoms start from day 0 to day 30 after most surgeries or within 90 days after surgeries where foreign bodies are inserted. PLUS |
| Involvement of skin, subcutaneous tissues, fascia, muscle, or viscera close to the surgical site. PLUS | |
| At least one of the following is present: purulent discharge from the site, positive culture for a non-commensal from a swab, a drain or an aspirated abscess, (incision was opened by a doctor or the wound dehisced with at least one of the following: localized pain or tenderness, localized swelling, erythema around the site, heat at the site, fever > 38°C), a diagnosis of surgical site infection as recorded by a doctor in the patient chart, a radiological imaging study that demonstrates the presence of an abscess near the surgical site. | |
| Note that a stitch abscess with minimal discharge and erythema is not considered an SSI and that the presence of infection at the time of surgery does not preclude the diagnosis of SSI. Patients who underwent multiple surgeries during the same admission are counted a single time. For the same surgery, an SSI cannot recur. | |
| VAP | DOE is > 48 hours after intubation or < 48 hours after extubation. PLUS |
| One chest x-ray or chest CT is consistent with pneumonia. PLUS | |
| Both of the following are present: (temperature > 38°C or < 36°C, OR WBC count ≥ 12,000 cells/mm3 or ≤ 4,000 cells/mm3) AND a new antimicrobial agent is started for ≥ 4 days (the same or different combinations of antibiotics may be used during these 4 days). PLUS | |
| At least one of the following is present: new onset or worsening hypoxia as defined by a drop of oxygen saturation (by ≥ 3% in SpO2 for the same FiO2) or a rise in FiO2 requirement (by ≥ 20%) or an increase in PEEP (by ≥ 3 cmH2O); new-onset septic shock with no other cause is recorded by the treating physician; an endotracheal aspirate (or other respiratory sample) or pleural fluid culture that is positive for a non-commensal; positive urine antigen test for Legionella sp. or Streptococcus pneumoniae; positive PCR test on endotracheal secretion, throat swab, or nasopharyngeal swab for an organism that is a non-commensal. | |
| Note that since most of the diagnoses of VAP in the study depended on culture results and it can take 5 to 7 days for doctors to receive culture results at that institution, the infection window period for VAP was increased to 15 days, i.e., 7 days before and 7 days after the DOE. Also, FiO2 and PEEP are not the main criteria for the diagnosis of VAP in the study since these are rarely recorded in a consistent manner in the charts. | |
| CLABSI | Central line is present for > 48 hours or was removed < 24 hours ago. PLUS |
| The identified organism is not related to an infection at another site. PLUS | |
| At least one of the following: a positive blood culture for a non-commensal or ≥ 2 positive blood cultures for a commensal in a patient that has at least fever > 38°C, chills, or hypotension. | |
| Note that a non-bacteremia catheter-related infection or vascular site infection is said to have occurred if a tip culture or pus culture at the site of insertion of the device is positive for a non-commensal and if at least one of the following is present: purulent discharge at the catheter site or the resolution of fever > 38°C, chills, or hypotension 48 hours after removal of the catheter. | |
| CAUTI | Urinary catheter is present for > 48 hours or was removed < 24 hours ago. PLUS |
| At least one of the following: fever > 38°C, suprapubic tenderness without any other cause, costovertebral angle pain, or tenderness without any other cause. PLUS | |
| A urine culture with at most two organisms that are not commensals. |