Can Brushing Teeth Before Surgery Prevent Postoperative Pneumonia?

A patient lies in a hospital bed, connected to medical equipment, breathing through an oxygen mask while battling pneumonia.

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Impact of Postoperative Pneumonia

Hospital-acquired pneumonia (HAP) is the most common hospital-acquired infection in the U.S. and has not shown improvement over time.¹ HAP is defined as pneumonia onset greater than 48 hours after admission to the hospital, and post-operative pneumonia (POP) is HAP that occurs after surgery.²

Postoperative complications, such as pneumonia, are important metrics that reflect the quality of surgical care. Despite efforts to improve it, POP is the third most common surgical complication and contributes to mortality as high as 32%, increased time in the hospital of 7 to 9 days, increased cost of $12,000 to $42,000, and chances of needing a higher level of care than home upon discharge.^2,3 Postoperative complications are reported to the Centers for Medicare & Medicaid, potentially affecting reimbursement.⁴

Acquiring pneumonia in the hospital is a risk factor for unplanned readmission. HAP leads to 140,000 readmissions annually, costing over $10 billion in extra hospital costs.⁴ Research demonstrates that 20% of patients with HAP will be readmitted within 30 days of discharge.^3,4

Once a patient develops POP, there is an increased risk of multiple complications, including sepsis.^5,6 Tevis et al. (2016) mined the ACS NSQIP database for 2005-2011 to analyze the frequency of postoperative complications.³ Of 470,108 general surgery patients, 15% experienced complications, including pneumonia, and 72% of patients with POP experienced multiple complications. POP was most strongly correlated with the complications of sepsis and failure to wean from the ventilator.³

Many cases of postoperative pneumonia (POP) are not diagnosed until after the patient's discharge. A study by Aasen et al. (2021) analyzed American College of Surgeons National Surgical Quality Improvement Program inpatient data from 2012-2017 to investigate 30-day postoperative infectious complications.⁷ The study found that 60% of these complications were discovered after the patient had been discharged, and of those, 26.5% were cases of pneumonia.⁷

Risk for Postoperative Pneumonia

The development of POP involves several factors, beginning with the colonization of the mouth, the aspiration of contaminated secretions, and weakened natural host defenses. Common pneumonia-causing bacteria include gram-negative, aerobic bacteria such as Pseudomonas, Klebsiella, and Enterobacter species and gram-positive bacteria such as methicillin-resistant Staphylococcus aureus.²

Most risk factors for POP are nonmodifiable and not conducive to preventive interventions. Older age, preoperative functional status, poor lung function, and diabetes were the most common risk factors for POP in multiple types of surgery, including general surgery, cardiovascular, orthopedic, and head and neck surgery.² These risk factors cannot be solved before, during, or after surgery, so we must focus on risk factors amenable to improvement.

What is the most modifiable risk factor for pneumonia? Pathogens in the mouth.⁸

Bacteria have been found in saliva even before patients undergo surgery, and the number of bacteria increases after surgery.⁹ A study evaluating the relationship between oral bacteria and the development of postoperative pneumonia (POP) found that bacteria in saliva on the first day after surgery was an independent risk factor for POP, with the bacteria type in saliva and lung matching 54% to 69% of the time.⁹ The good news is that oral care before surgery has been shown to dramatically reduce the number of oral bacteria.⁹

Prevention with Perioperative Oral Hygiene

Preventing hospital-acquired pneumonia with oral care is an essential strategy in the 2022 national guidelines¹¹ and is the only recommended strategy for preventing pneumonia that addresses the most modifiable risk factor and source of infection: pathogens in the mouth.

Professional oral hygiene before the surgical procedure has been shown to reduce the risk for HAP, including POP. A study involving over one million Medicaid beneficiaries found that those who received preventive dental treatment within the year or periodontal services less than 6 months before surgery were 10% and 30%, respectively, less likely to acquire HAP.¹²

Additionally, a retrospective study on patient outcomes with lung resection due to cancer found that the group receiving perioperative oral hygiene, including professional cleaning and plaque removal, experienced significantly less postoperative pneumonia (POP) compared to those who did not receive oral care.¹³

Whether the patient has seen the dentist before surgery or not, oral hygiene on the day of surgery is crucial for preventing postoperative pneumonia (POP). Studies show that brushing teeth and using an antiseptic mouth rinse perioperatively reduces POP and surgical site infections.¹⁴ Patients who received preoperative oral care had significantly lower POP incidence, highlighting its importance.^14,15

Implications and Recommendations

Postoperative pneumonia (POP) is a common complication of surgery that affects patients and health care organizations. Although many risk factors for POP are impossible to change, timely oral hygiene can reduce the bacteria in the mouth that causes pneumonia.¹⁰ If possible, every surgery patient should have a professional dental cleaning before surgery. Additionally, patients should brush their teeth with a soft-bristled toothbrush and use antiseptic mouth rinse immediately before and frequently after surgery. Patients and health care professionals should be educated, and surgery protocols should include pre and postoperative oral hygiene to prevent this harmful infection.

References

1. Magill SS, O’Leary SJ, Janelle DL, et al. Changes in prevalence of healthcare-associated infections in US hospitals. N Engl J Med. 2018;379(18):1732-1744. doi:10.1056/NEJMoa1801550.
2. Chughtai M, Gwam CU, Mohamed N, et al. The epidemiology and risk factors for postoperative pneumonia. J Clin Med Res. 2017;9(6):466-475.
3. Tevis SE, Cobian AG, Truong HP, et al. Implications of multiple complications on the postoperative recovery of general surgery patients. Ann Surg. 2016;263(6):1213-1218.
4. De Alba I, Amin A. Pneumonia readmissions: Risk factors and implications. Ochsner J. 2014;14(4):649-654.
5. Giuliano KK, Baker D. Sepsis in the context of nonventilator hospital-acquired pneumonia. Am J Crit Care. 2020;29(1):9-14.
6. Mayr FB, Yende S, Angus DC. Epidemiology of severe sepsis. Virulence. 2013;5(1):4-11.
7. Aasen DM, Bronsert MR, Rozeboom PD, et al. Relationships between predischarge and postdischarge infectious complications, length of stay, and unplanned readmissions in the ACS NSQIP database. Surgery. 2021;169:325-332.
8. Schleder B, Stott K, Lloyd R. The effect of a comprehensive oral care protocol on patients at risk for ventilator-associated pneumonia. J Advocate Health. 2002;27-30.
9. Sakamoto Y, Tanabe A, Moriyama M, et al. Number of bacteria in saliva in the perioperative period and factors associated with increased numbers. Int J Environ Res Public Health. 2022;19:7552.
10. Sakamoto K, Tamesa T, Tokuhisa Y, et al. Perioperative microbiologic monitoring of sputum on postoperative day one as a predictor of pneumonia after hepatectomy. J Gastrointest Surg. 2015;19:1662-1667.
11. Klompas M, Branson R, Cawcutt K, et al. Strategies to prevent ventilator-associated pneumonia, ventilator-associated events, and nonventilator hospital-acquired pneumonia in acute-care hospitals: 2022 update. Infect Control Hosp Epidemiol. 2022;43:687-713.
12. Baker D, Giuliano KK, Thakkar-Samtani M, et al. The association between accessing dental services and nonventilator hospital-acquired pneumonia among 2019 Medicaid beneficiaries. Infect Control Hosp Epidemiol. 2022;1-3.
13. Iwata E, Hasegawa T, Yamada S, et al. Effects of perioperative oral care on postoperative pneumonia prevention after lung resection: Multicenter retrospective study with propensity score matching analysis. Surgery. 2019;165:1003-1007.
14. Pedersen PU, Larsen P, Hakonsen SJ. The effectiveness of systematic perioperative oral hygiene in reduction of postoperative respiratory tract infections after elective thoracic surgery in adults: A systematic review. JBI Database Syst Rev Implement Rep. 2016;14(1):140-173.
15. Soutome S, Yanamoto S, Funahara M, et al. Effect of perioperative oral care on preventing postoperative pneumonia associated with esophageal cancer surgery: A multicenter case-control study with propensity score matching analysis. Medicine (Baltimore). 2017;96(33):1-5.