1. Talley, Louise PhD, RN
  2. Lamb, Jennifer MS, RN, GCNS
  3. Harl, Jami MS, CCC-SLP
  4. Lorenz, Heather MSN, RN
  5. Green, Lindsey MN, APRN-CNS, CCNS, RNC-NIC

Article Content

Hospital-acquired pneumonia (HAP) has become a costly and dangerous healthcare issue. An estimated 200,000 cases of aspiration pneumonia occur every year in the United States, resulting in more than 15,000 deaths.1 HAP causes unnecessary patient suffering, mortality as high as 20% to 30%, and significantly increased length and cost of hospital stay.2,3 As reported by the American Thoracic Society and the Infectious Diseases Society of America, treatment of HAP costs approximately $40,000 per patient.4 Most of this incidence and outcome information is collected from patients with ventilator-associated pneumonia (VAP). By deduction, information regarding VAP can be applied to patients with HAP.4 Given that HAP is one of the most common hospital-acquired infections, evidence-based prevention could save the healthcare industry several billion dollars annually.5

Figure. No caption a... - Click to enlarge in new windowFigure. No caption available.

Relation between HAP and dental health

Considerable evidence supports a relation between poor oral health and bacterial pneumonia. In a systematic review of evidence for an association between oral health and pneumonia, experts found that cariogenic and periodontal pathogens, dental decay, and poor oral hygiene are potential risk factors for pneumonia.6 In addition, poor oral hygiene has been linked to significant increases in the numbers of febrile days and cases of pneumonia.7


Specifically, dental plaque is composed of a complex population of more than 700 different bacterial species.8 Poor dental hygiene can result in continual bacterial cell growth and increased bacterial diversity within dental plaque. Without proper dental hygiene, dental plaque may serve as a reservoir for respiratory pathogens in hospitalized patients. Matching organisms have been found in dental plaque and bronchoalveolar lavage fluid from patients with HAP, implicating aspiration of organisms within dental plaque as the etiology of HAP in these patients.9 This is thought to occur via a mechanism in which aspirated respiratory pathogens shed from oral biofilm access into the lower airway, increasing the risk of pneumonia.10


Given the excess costs of treating HAP, along with increased morbidity and mortality, numerous studies have investigated clinical practices that can reduce its incidence. Systematic reviews indicate a positive preventive impact of oral hygiene on pneumonia and respiratory infections.6,11 Supporting this finding, one group of researchers recently reported that the rate of nonventilated (NV)-HAP per 100 patient days decreased from 0.49 to 0.3 (38.8%) after implementation of an oral care program.12 The overall number of cases of NV-HAP was reduced by 37% during a 12-month intervention period. In addition, an estimated eight lives were saved, $1.72 million in costs were avoided, and 500 extra hospital days were averted.12


In another study, implementation of an oral care protocol for nonICU medical patients demonstrated that an oral care protocol aided in reducing HAP incidence and may have improved nutritional intake.13 Patients in pre- and postintervention groups received oral care based on assessment of their risk level. HAP cases decreased from 10 in the preintervention group to 2 in the postintervention group.13 Therefore, the implementation of oral care interventions to reduce or control the amount of dental plaque may be a simple, cost-effective method for reducing pathogen colonization in high-risk populations.14


In additional studies, various tested mechanical methods have been shown to significantly reduce HAP incidence. These methods include a suctioning toothbrush, a traditional toothbrush versus a foam swab, and tooth brushing after every meal without a dentifrice for 5 minutes.15-17 In addition to these and other various interventions, HAP incidence is significantly reduced in postoperative patients when used as part of a total oral care program that also includes staff and physician education.18


In general, oral care is often omitted by nurses, despite its importance in preventing infection.19 Any successful initiative to reduce HAP incidence should incorporate a strategy for increasing participation of all nursing staff. Successful programs should also include implementation of policies that allow for adequate time, proper oral care supplies, ease of access to supplies, standardized procedures, and outcome monitoring to ensure that patients are protected from NV-HAP.


To date, a large amount of research has focused on decreasing the incidence of pneumonia in ICU patients and preventing VAP. Few studies have reported on NV patients in the acute care setting. The purpose of our study was to determine the efficacy of an oral care program for NV stroke and medical-surgical patients to reduce the incidence of HAP, risk of acquiring HAP, length of NPO (nothing by mouth) status, and hospitalization length of stay (LOS).


Program intervention

Before implementation of the oral care program, RNs and unlicensed assistive personnel (UAPs) caring for patients on a progressive care unit, a stroke unit, and two medical units attended a training session with content that included the following: impact of HAP on patients and families, the role of the RN and UAP in HAP prevention, step-by-step review of the oral care program, electronic medical record documentation, and demonstrated use of the oral hygiene kit.


Structured oral care intervention for high-risk patients: Patients with a HAP risk score >=6 received the following interventions: 1) mechanical cleansing with a suction toothbrush and 0.05% cetylpyridinium chloride antiseptic mouthwash every 12 hours, 2) debridement with oral swab every 4 to 6 hours, 3) suction to remove waste/secretions, 4) application of mouth moisturizer to lips and mouth every 4 hours, and 5) care performed before eating each meal.


Structured oral care intervention for low-risk patients: Patients with a HAP risk score <6 were considered at low risk and provided standard care, which included a toothbrush, toothpaste, and mouthwash containing propylene glycol, and were reminded to perform (or assisted with performing) oral care every 12 hours.


Data collection and analysis: Data were collected via retrospective chart review by nurse data collectors after patient discharge. Mean differences were analyzed for postintervention patients having both initial HAP risk scores and final HAP risk scores before discharge (n = 285). Data were analyzed using predictive analytics software. An independent t-test with a significance level of p = 0.05 was performed to compare group means of interval-level data for the intervention and comparison groups.



Postintervention patients had an average initial HAP risk score of 0.87 upon entering the study. After participation in the structured oral care program, the mean final HAP risk score was 0.65. As shown in Table 2, a 25% reduction in HAP risk score was observed for patients after participating in the oral care program. The statistically significant difference (p = 0.013) in HAP risk score during hospitalization indicates that the oral care program was effective in reducing HAP risk.

Table 2: Paired diff... - Click to enlarge in new windowTable 2: Paired differences in initial and final HAP risk scores in the postintervention group (n = 285)

HAP incidence was documented before and after implementation of the oral care program. The progressive care unit reported that five patients acquired HAP before oral care program implementation. (See Table 3.) After implementation, zero cases of HAP were reported. In the stroke unit, one case of HAP was reported during both the pre- and postintervention periods. No cases of HAP were reported pre- or postintervention on the two medical units. In summary, a total of six HAP cases were reported before oral care program implementation, and one case was reported after implementation. The reduction of HAP incidence had a p value of 0.067, suggesting that whereas these results may be clinically significant, they lacked statistical significance (p = 0.05).

Table 3: Incidence o... - Click to enlarge in new windowTable 3: Incidence of patients with HAP

Regarding NPO status, an independent samples t-test was performed to compare the mean scores of patients admitted and discharged in 2010, before the structured oral care program, and patients who received the structured oral care program. As shown in Table 4, the mean time for NPO status for stroke patients decreased from 2.4 days to 0.24 days (p = 0.069). Although statistical significance wasn't reached (p = 0.05), a clinically significant reduction in time of NPO status was observed.

Table 4: Mean NPO da... - Click to enlarge in new windowTable 4: Mean NPO days for patients with stroke

Regarding LOS, an independent samples t-testwas performed to compare the mean scores of stroke patients admitted and discharged before the structured oral care program and patients who received the structured oral care program. (See Table 5.) The average LOS was 9.45 days for the preintervention group and 6.92 days for patients who participated in the structured oral care program. The 2.5-day reduction in LOS had a p value of 0.122; however, the reduction in LOS was clinically significant.

Table 5: Mean LOS fo... - Click to enlarge in new windowTable 5: Mean LOS for patients with stroke

Return on investment

On implementation of the structured oral care program, five fewer cases of HAP were reported than before implementation. With estimated treatment costs of approximately $40,000 per patient, our hospital saved approximately $200,000 by reducing HAP incidence.12,21 Subtracting the price of the oral care kits, the estimated return on investment for the present study was $195,400.


We found that implementation of a structured oral care program reduced patients' risk for acquiring a life-threatening HAP infection. In addition, clinically significant findings suggested that a structured oral care program can reduce HAP incidence, length of NPO status, and overall LOS. The present results support those of previous studies, which suggest that improved oral care can reduce the occurrence of pneumonia and other respiratory infections. The mortality for HAP is high, and the cost and financial burden of HAP treatment are great. A fairly simple oral care quality improvement initiative can save multiple lives-and billions of dollars a year for the healthcare industry. This study alone saved four units approximately $200,000 in the first year of implementation. It also improved the oral care that patients received from the nursing staff, most likely by increasing awareness of the importance of proper oral care in reducing HAP and other respiratory infections. In addition, this program implemented a convenient oral care bundle, which made providing oral care to patients more convenient and accessible.


There are a few limitations of the present study. Given that the sample consisted of four medical-surgical units, the research findings may not be generalizable to the broader population. Methodological limitations included lack of randomization. As discussed, decreases in HAP incidence, length of NPO status, and hospital LOS were clinically, but not statistically, significant.


To measure the impact of the structured oral care program on HAP incidence, we used Cohen's d formula.22 The calculated effect size was 0.20, indicating that the oral care program did, in fact, have a small effect on HAP incidence, although no statistically significant reduction in HAP incidence was observed. These results require a larger sample size and possible inclusion of medical units with higher initial HAP incidence to obtain statistically significant data.


In addition, the study didn't control for other factors affecting hospital LOS, resulting in large standard deviations from the mean that made the acquisition of statistically significant data difficult. It's possible that a larger sample size and a unit with a higher initial incidence of HAP may yield data showing statistical significance.


An example for others

This study stresses the importance of providing proper oral care for patients. In addition, the research demonstrates the importance of proper education and implementation practices to increase awareness and make oral care a priority for nursing staff. Rollout of a convenient oral care program that took into account patient risk scores for HAP resulted in clinically relevant reductions in HAP incidence, length of NPO status, and hospital LOS. Adoption of this method may help reduce HAP risk at other hospitals, ultimately reducing patient pain and suffering, while simultaneously reducing the financial burden of hospital-acquired infections on the healthcare industry.


Materials and methods

Ethics approval

Our facility's Institutional Review Board approved the study and provided a waiver due to the deidentified nature of the data.


Clinical setting

This study was conducted on four adult medical-surgical nursing units in an acute care medical center. The four medical units consisted of one progressive medical unit, one stroke unit, and two medical units as follows:


* 8 West (progressive care unit)-23 beds


* 9 West (certified stroke unit)-28 beds


* 11 East (medical-surgical)-32 beds


* 12 East (medical-surgical)-22 beds.



Experimental design

This was a quasi-experimental study, with posttest-only analysis and nonequivalent comparison groups. Sampling of two NV adult study groups from four nursing units yielded data on 347 preintervention patients who were admitted and discharged in 2010, before the structured oral care program was implemented, and 337 postintervention patients, who participated in the structured oral care program. Demographic data are presented in Table 1. NV patients age 18 or older from the four participating nursing units were selected for this study. Patients were excluded from this study if their LOS was less than 3 calendar days, if they were ventilated on the ICU, or if they were transferred to the unit from an ICU with VAP. For each patient, we collected demographic data, LOS, daily average for number of times oral care was provided in three consecutive days, number of NPO days, and presence or absence of HAP.

Table 1: Demographic... - Click to enlarge in new windowTable 1: Demographic data


HAP incidence. Criteria for HAP diagnosis were developed according to the CDC/National Healthcare Safety Network clinically defined pneumonia criteria.20 For diagnosis, a patient must have had two or more serial chest radiographs with a new or progressive and persistent infiltrate, consolidation, and/or cavitation. In addition, a patient must have had a fever; leukocytosis; or in the case of older adult patients (age 70+ years), altered mental status with no other recognized cause. The patient must also have had at least two of the following: 1) new onset of purulent sputum or change in character of sputum, increased respiratory secretions, or increased suctioning requirements; 2) new onset or worsening cough, dyspnea, or tachypnea; 3) crackles or bronchial breath sounds; and 4) worsening gas exchange or increased oxygen requirements.


HAP risk. Criteria for HAP risk assessment were developed and optimized for this study. Postintervention patients were assessed every 12 hours for oral status and deemed low risk (score 0-5) or high risk (score >6). Patients with nasal or gastric tubes, swallowing disorders, aspiration history, oral suctioning, continuous NPO status, bi-level positive airway pressure masks, or tracheostomy were automatically considered high risk for HAP and received a score of 6. In the absence of these conditions, patients received a score of 0 to 2, with 0 being normal and 2 severe, for each of the following: condition of the gums, condition of the lips/corners of the mouth, swallowing and chewing ability, and feeding/oral care ability. For each patient, the scores were combined and recorded as the patient's HAP risk score.


NPO status was defined operationally as preventing the patient from any oral intake in the form of nutrition, medication, ice chips, or sips of water. NPO days represented those days that the patient was at high risk for aspiration of nutrition or medication via the oral route.




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