The triple threat of aspiration pneumonia

Aspiration Pneumonia

Aspiration pneumonia is a lower respiratory tract infection that results from inhalation of foreign material, often gastric and oropharyngeal contents. It is important to distinguish this from a similar entity, aspiration with chemical pneumonitis, as treatment approaches may differ. An evolving understanding of the human microbiome has shed light on the pathogenesis of aspiration pneumonia, suggesting that dysbiosis, repetitive injury, and inflammatory responses play a role in its development. Risk factors for aspiration events involve a complex interplay of anatomical and physiological dysfunctions in the nervous, gastrointestinal, and pulmonary systems. Current treatment strategies have shifted away from anaerobic organisms as leading pathogens. Prevention of aspiration pneumonia primarily involves addressing oropharyngeal dysphagia, a significant risk factor for aspiration pneumonia, particularly among elderly individuals and those with cognitive and neurodegenerative disorders.

Evaluation of Donor Lungs for Transplantation: The Efficacy of Screening Bronchoscopy for Detecting Donor Aspiration and Its Relationship to the Resulting Allograft Function in Corresponding Recipients

BACKGROUND

Potential organ donors often have suffered anoxic and/or traumatic brain injury during which they may have experienced aspiration of gastric material (AGM). Evaluation of such donors typically includes a screening bronchoscopic examination during which determinations of aspiration are made. The efficacy of this visual screening and its relationship to post-transplant allograft function are unknown.

METHODS

Before procurement, bronchoscopy was performed on donors in which both bronchoalveolar lavage fluid (BALF) was collected and a visual inspection made. As a marker of AGM, BALF specimens were analyzed for the presence of bile salts. Data collected on the corresponding recipients included primary graft dysfunction (PGD) score, post-transplant spirometry, acute rejection scores (ARS), and overall survival.

RESULTS

Of 31 donors evaluated, bronchoscopies revealed only 2 with visual evidence of AGM, whereas BALF analysis for bile salts indicated AGM in 14. As such, screening bronchoscopy had a sensitivity of only 7.1%. Visual detection of AGM via bronchoscopy was not associated with any resulting grade of PGD (χ2 = 2.96, P = .23); however, AGM defined by detection of bile salts was associated (χ2 = 7.56, P = .02). Over the first post-transplant year, the corresponding recipients experienced a similar improvement in allograft function (χ2 = 1.63, P = .69), ARS (P = .69), and survival (P = .24).

CONCLUSION

Visual inspection during a single bronchoscopic examination of lung donors underestimates the prevalence of AGM. The detection of bile salts in donor BALF is associated with early allograft dysfunction in the corresponding recipients but not with later allograft proficiency, acute rejection responses, or 1-year post-transplant survival.

Diffuse Aspiration Bronchiolitis With Neuromyelitis Optica Spectrum Disorder

Diffuse aspiration bronchiolitis (DAB) is a chronic inflammatory response of the bronchioles caused by repeated aspiration of foreign bodies. It is common among older individuals with dysphagia associated with neurological diseases or dementia. Here, we present the case of a woman in her 40s who was presumed to have developed DAB due to neuromyelitis optica spectrum disorder (NMOSD). There have been no reports of DAB due to NMOSD. The absence of obvious episodes of aspiration and the fact that pneumonia was the predominant symptom delayed the diagnosis despite the appearance of specific neurological abnormalities. DAB caused by neurological diseases of the brainstem should be considered in younger patients with diffuse centrilobular opacities, even if dysphagia is not obvious.

Presbyphagia: Dysphagia in the elderly

Dysphagia has been classified as a “geriatric syndrome” and can lead to serious complications that result in a tremendous burden on population health and healthcare resources worldwide. A characteristic age-related change in swallowing is defined as “presbyphagia.” Medical imaging has shown some changes that seriously affect the safety and efficacy of swallowing. However, there is a general lack of awareness of the effects of aging on swallowing function and a belief that these changes are part of normal aging. Our review provides an overview of presbyphagia, which has been a neglected health problem for a long time. Attention and awareness of dysphagia in the elderly population should be strengthened, and targeted intervention measures should be actively implemented.

Sphingomonas Paucimobilis Pneumonia Complicated by Empyema in an Immunocompetent Patient: A Case Report and Concise Review of Literature

Sphingomonas paucimobilis is an aerobic, Gram-negative bacterium that is found widely in the environment and on hospital equipment. Although this organism usually causes infection in immunocompromised patients, it may cause pulmonary disease in immunocompetent patients, in rare cases. We report a case of Sphingomonas paucimobilis pneumonia complicated by empyema in an immunocompetent patient. We present a case of a 59-year-old female who was admitted for a congestive heart failure exacerbation and pneumonia. After imaging confirmed pneumonia and pleural effusion, monotherapy with levofloxacin was started. Thoracentesis revealed empyema caused by Sphingomonas paucimobilis. Despite chest tube placement, thoracoscopy with decortication was required due to continued clinical deterioration. After surgical intervention and an adjusted antibiotic regimen of cefepime, the patient clinically improved and was discharged. Upon follow-up, she had recovered completely with no residual disease. Alongside a concise review of the literature, our study highlights the importance of this infection in immunocompetent patients and advises providers to identify causes of aspiration when Sphingomonas paucimobilis empyema is diagnosed.

Case Report: Next-Generation Sequencing in Diagnosis of Atypical Aspiration Pneumonia

Since the pandemic of Corona Virus Disease 2019 (COVID-19), especially in the centers most affected, the symptoms such as fever, cough, myalgia or fatigue, and radioactive signs typically related to COVID-19 like ground-glass opacity (GGO) often distract the attention of physicians from other diseases. Aspiration pneumonia and COVID-19 share similarities in some aspects. There may be risk of misdiagnosis in the case of considering radiological patterns of pneumonia. Early diagnosis and treatment often greatly improve prognosis. We herein reported a case of 40-year-old patient who underwent chest CT scan with the discovery of ground-glass opacity, intralobular reticular opacity and interlobular septal thickening, consolidation, and air bronchogram sign, which were mainly located in the middle and upper lobes of the right lung. It was considered to be infection related pneumonia based on the negative reverse transcription-PCR (RT-PCR) result of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The next-generation sequencing (NGS) of bronchoalveolar lavage fluid (BALF) was performed and detected nucleic acid sequences of Klebsiella sp. Consequently, the patient accepted sensitive intravenous antibiotics therapy for 13 days and had a remarkable clinical and radiological improvement. His case was followed up through imaging procedures. Because of possible radiologic and clinical similarities between aspiration and COVID-19 pneumonia, COVID-19 can be of some value in proposing a differential diagnosis of aspiration pneumonia. Clinicians could suggest a correct diagnosis by careful examination of the CT images together with attention to the clinical history and judicious utilization of NGS, especially.

Aspiration syndromes and associated lung injury: incidence, pathophysiology and management

Aspiration is a common condition affecting healthy or sick patients which could create an acute or chronic inflammatory reaction in the lungs. Aspiration syndromes could be categorized according to a content entering the respiratory system into bacterial aspiration pneumonia with the gastric or oropharyngeal bacteria entering, aspiration chemical pneumonitis with bacteria-freegastric acid aspiration, or aspiration of a foreign body which causes an acute pulmonary emergency. There are differences in the clinical presentation of volume-dependent aspirations (microaspiration and macroaspiration): the higher is the volume of aspiration, the greater is the injury to the patient and more serious are the health consequences (with 70 % mortality rate for hospitalized patients). Aspiration syndromes can affect both the airways and pulmonary parenchyma, leading to acute lung injury, increased hospitalization rate and worse outcomes in critically ill patients. Impaired alveolar-capillary permeability, oedema formation, neutrophilic inflammatory response and pulmonary surfactant inactivation lead to reduced lung compliance and loss of aerated lung tissue and give rise to hypoxemia and respiratory failure. This review discusses the effect of aspiration events on the pulmonary tissue. The main focus is to distinguish the differences between bacterial and chemical pneumonia, their clinical presentation and symptoms, risk factors of developing the changes, possibilities of diagnostics and management as well as prevention of aspirations. Because of a risk of serious lung damage after the aspiration, pathophysiology and processes leading to lung tissue injury are discussed in detail. Data sources represent a systematic literature search using relevant medical subject headings.

Porphyromonas gingivalis Components/Secretions Synergistically Enhance Pneumonia Caused by Streptococcus pneumoniae in Mice

Streptococcus pneumoniae is an important causative organism of respiratory tract infections. Although periodontal bacteria have been shown to influence respiratory infections such as aspiration pneumonia, the synergistic effect of S. pneumoniae and Porphyromonas gingivalis, a periodontopathic bacterium, on pneumococcal infections is unclear. To investigate whether P. gingivalis accelerates pneumococcal infections, we tested the effects of inoculating P. gingivalis culture supernatant (PgSup) into S. pneumoniae-infected mice. Mice were intratracheally injected with S. pneumoniae and PgSup to induce pneumonia, and lung histopathological sections and the absolute number and frequency of neutrophils and macrophages in the lung were analyzed. Proinflammatory cytokine/chemokine expression was examined by qPCR and ELISA. Inflammatory cell infiltration was observed in S. pneumoniae-infected mice and S. pnemoniae and PgSup mixed-infected mice, and mixed-infected mice showed more pronounced inflammation in lung. The ratios of monocytes/macrophages and neutrophils were not significantly different between the lungs of S. pneumoniae-infected mice and those of mixed-infected mice. PgSup synergistically increased TNF-α expression/production and IL-17 production compared with S. pneumoniae infection alone. We demonstrated that PgSup enhanced inflammation in pneumonia caused by S. pneumoniae, suggesting that virulence factors produced by P. gingivalis are involved in the exacerbation of respiratory tract infections such as aspiration pneumonia.

[Intraoperative Aspiration]

术中误吸是外科手术中常见的肺部并发症，麻醉和体位是导致术中误吸的主要因素。近年来，围手术期肺保护已受到外科和麻醉医师的广泛关注，如何加速术后康复进程，减少相关并发症发生，显著改善患者预后已成为当前外科治疗的主要目标。本文将以术中误吸为重点，从解剖、病理生理、表现、诊断、处理和预防等方面展开综述。

Comparison of ceftriaxone plus macrolide and ampicillin/sulbactam plus macrolide in treatment for patients with community-acquired pneumonia without risk factors for aspiration: an open-label, quasi-randomized, controlled trial

Background

Ceftriaxone (CTRX) and ampicillin/sulbactam (ABPC/SBT) are recommended by various guidelines as the first-line antibiotics for community-acquired pneumonia (CAP). However, which of these antibiotics is more effective for treating non-aspiration CAP remains unclear.

Methods

This study was a prospective, single-center, open-label, quasi-randomized controlled trial. Patients with adult CAP without risk for aspiration were allocated to either a CTRX or ABPC/SBT group based on the date of hospital admission. Macrolide was added to patients in each group. The primary outcome was the clinical response in the validated per-protocol (VPP) population at end of treatment (EOT). The secondary outcomes were clinical response during treatment and at end of study (EOS) in the VPP population, and mortality rate at day 30 in the modified intention-to-treat (MITT) population.

Results

Of 696 screened patients, 433 patients were excluded and 263 patients were allocated to receive either of the treatments. Males comprised 54% of patients and mean age and PSI were 62.1 ± 19.8 years and 69.3 ± 30.0, respectively, with 124 patients allocated to the CTRX group and 138 patients allocated to the ABPC/SBT group. The clinical effectiveness rate for the VPP population at EOT was 90% in the CTRX and 96% in the ABPC/SBT group (p = 0.072, 95% confidence interval [CI] of risk difference [RD]: − 12.6–0.8%). No significant difference in effectiveness at day 4 was observed between the CTRX and ABPC/SBT groups (p = 0.079, 95%CI of RD: − 12.1–0.4%), but at day 7, ABPC/SBT was significantly more effective than CTRX in the VPP population (p = 0.047, 95%CI of RD: − 13.3–-0.4%). No significant difference in late response at EOS was seen between CTRX and ABPC/SBT groups: cure (89 [86%] and 102 [94%]), relapse (5 [5%] and 1 [1%]) and failure (10 [10%] and 5 [5%]; p = 0.053). Deaths within 30 days in MITT population was higher in CTRX group (4 [3%]) than in ABPC/SBT group (0 [0%]) (p = 0.048, 95%CI of RD: 0.1–6.3%).

Conclusion

No significant difference in effectiveness was found between ABPC/SBT and CTRX at EOT. However, ABPC/SBT might be more effective in the early phase of treatment.

Trial registration

UMIN-CTR, UMIN000037464. Registered 25 July 2019 – Retrospectively registered, https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000042262

Aspiration pneumonia and pneumonitis: a spectrum of infectious/noninfectious diseases affecting the lung

PURPOSE OF REVIEW

Our purpose is to describe aspiration pneumonia/pneumonitis as a spectrum of infectious/noninfectious diseases affecting the lung. We summarize diagnosis, risk factors, treatment, and strategies for prevention of aspiration.

RECENT FINDINGS

Aspiration is present in normal individuals, and disease manifestation depends on the chemical characteristics, frequency, and volume of inoculum. Anaerobes, though present, are no longer the predominant microbes isolated in aspiration pneumonia. Targets for preventing aspiration including improved oral hygiene and positional feeding have had mixed results. Patients diagnosed by clinicians with aspiration pneumonia experience greater morbidity and mortality than patients with community-acquired pneumonia.

SUMMARY

Aspiration pneumonia and pneumonitis are part of the pneumonia continuum and share similarities in pathophysiology, microbiology, and treatment. Modern microbiology demonstrates that the lung is not sterile, and isolates in aspiration pneumonia frequently include aerobes or mixed cultures. Treatment for aspiration pneumonia should include antibiotic coverage for oral anaerobes, aerobes associated with community-acquired pneumonia, and resistant organisms depending on appropriate clinical context. Additional studies targeting prevention of aspiration and investigating the increased morbidity and mortality associated with aspiration pneumonia are warranted.

Ceftriaxone versus ampicillin/sulbactam for the treatment of aspiration-associated pneumonia in adults

Aim: To compare hospital mortality in patients with aspiration-associated pneumonia treated with ceftriaxone (CTRX) and in those treated with ampicillin/sulbactam (ABPC/SBT). Methods: From a Japanese multicentre observational study cohort of patients with pneumonia, those diagnosed with pneumonia and having at least one aspiration-related risk factor were selected. Propensity score-matching analysis was used to balance baseline characteristics of the participants and compare hospital mortality of patients treated with CTRX and those treated with ABPC/SBT. Results: Hospital mortality did not significantly differ between patients treated with CTRX and those treated with ABPC/SBT (6.6 vs 10.7%, risk difference -4.0, 95% CI [-9.4, 1.3]; p = 0.143). Conclusion: Further studies are needed to compare CTRX and ABPC/SBT treatments in patients with aspiration-associated pneumonia.

New perspectives in aspiration community acquired Pneumonia

Introduction: Aspiration pneumonia is a subclass of community-acquired pneumonia that is expected to have an increasing contribution in mortality and morbidity, particularly in the elderly population over the next coming decades. While studies have revealed significant progress in identifying risk factors for aspiration pneumonia, the clinical presentation and diagnosis remain challenging to healthcare providers. Areas covered: We conducted a broad literature review using the MeSH heading in PubMed/MEDLINE of 'aspiration pneumonia' from January 1970 to July 2019. The understanding of the microbiology of aspiration pneumonia has evolved from a possible shift in the causative organisms away from anaerobes to traditional community-acquired pneumonia organisms. The importance of this shift is not yet known, but it has questioned the pathogenic role of anaerobes, appropriate anaerobic testing and the role of these pathogens in the pulmonary microbiome in patients with pneumonia. The identification of risk factors led to strategies to prevent or minimize the risk of aspiration pneumonia with moderate success. Expert opinion: Our expert opinion is that further research is needed to determine the role of the microbiome with aspiration pneumonia and patient risk factors. There is also a great need to develop clinical tools to help providers diagnose, treat, and prevent aspiration pneumonia.

Prevotella intermedia and periodontitis are associated with severe asthma

BACKGROUND

Periodontitis, an inflammatory disease of multibacterial etiology that affects the protective and supporting tissues surrounding teeth, can influence the course of respiratory diseases, such as asthma, due to epithelial alterations arising from inflammatory and immunological processes, bronchial remodeling, or by the aspiration of pathogenic colonizers found in periodontal pockets. This study evaluated the levels of periodontal pathogens Prevotella intermedia, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Aggregatibacter actinomycetemcomitans in the subgingival biofilm of individuals with and without severe asthma.

METHODS

A case-control study enrolling 457 individuals (220 with asthma and 237 without asthma) was conducted at the Program for Control of Asthma in Bahia (ProAR) Clinic located in Salvador, Bahia, Brazil. A structured questionnaire was used to obtain data on sociodemographic, health status, and lifestyle habits. A clinical periodontal assessment was performed, including bleeding on probing, probing depth, and clinical attachment level. Subgingival biofilm was collected at the deepest site of each sextant, and bacterial DNA was extracted. Quantitative real-time PCR analysis was performed to detect and relatively quantify periodontopathogens in the biofilm.

RESULTS

Statistically significant positive associations were found between periodontitis and severe asthma, (odds ratio [OR]_adjusted] : 4.00; 95% confidence interval [CI]: 2.26 to 7.10). High levels of P. intermedia were found in association with the presence of severe asthma (OR_adjusted : 2.64; 95% CI: 1.62 to 4.39; P < 0.01).

CONCLUSIONS

The present results suggest that periodontitis and P. intermedia are associated with severe asthma. However, the functional consequences of this dysbiosis upon asthma susceptibility and its phenotypes remain unclear.

Comparison of the in Vivo Activities of Garenoxacin and Levofloxacin in a Murine Model of Pneumonia by Mixed-Infection with Streptococcus pneumoniae and Parvimonas micra

Community-acquired pneumonia (CAP) can involve mixed-species bacterial infection. However, few studies have investigated antimicrobial efficacy in the treatment of mixed species infections. This study aimed to compare the in vivo antimicrobial activity of garenoxacin (GRNX) and levofloxacin (LVFX) against Streptococcus pneumoniae and Parvimonas micra in a murine model of mixed species bacterial pneumonia. S. pneumoniae D-6888 and P. micra No. 242 were used in this study. Antimicrobial activity toward each isolate was calculated as the change in bacterial count in the lungs (Δlog₁₀ CFU/mL) of mice after 24 h of treatment compared with the count in pretreated animals (0 h). The MICs of GRNX and LVFX against S. pneumoniae D-6888 were 0.06 and 0.5 mg/L and the MICs against P. micra No. 242 were 0.03 and 0.12 mg/L, respectively. In a murine pneumonia mixed-infection model, GRNX showed significantly higher in vivo antimicrobial activity against S. pneumoniae than LVFX (GRNX; －2.02 ± 0.99 log₁₀ CFU/mL vs. LVFX; －0.97 ± 0.61 log₁₀ CFU/mL, p = 0.0188). GRNX displayed about 2-fold more potent activity against P. micra than LVFX (GRNX; －1.12 ± 0.56 log₁₀ CFU/mL vs. LVFX; －0.61 ± 0.43 log₁₀ CFU/mL, p = 0.1029). These results suggest that GRNX is preferable for the treatment of mixed species bacterial CAP.

Long-Term Mortality and Prognostic Factors in Aspiration Pneumonia

OBJECTIVES

Aspiration pneumonia is a leading cause of death among older patients; however, little is known about the long-term mortality in aspiration pneumonia. The purpose of this study was to evaluate long-term mortality and its associated factors in patients with aspiration pneumonia.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

In total, 550 patients with aspiration pneumonia (median age: 78.0 years, 66.4% male) with compatible clinical symptoms and chest computed tomography images were enrolled at a single tertiary center from 2006 to 2016.

MEASURES

The 1-, 3-, and 5-year mortality rates were evaluated for all patients. The prognostic factors for 1-year and 5-year mortality were also evaluated using Cox proportional hazard models.

RESULTS

A total of 441 (80.2%) patients died during a median follow-up of 50.7 weeks. The 1-, 3-, and 5-year mortality rates were 49.0%, 67.1%, and 76.9%, respectively. Multivariate analysis identified 5 risk factors for 1-year mortality of male sex [hazard ratio (HR) 1.533, P = .003], low body mass index (HR 0.934, P = .002), hypoalbuminemia, anemia (0.973, P = .032), and mechanical ventilation (HR 2.052, P < .001), which were also independent prognostic factors for 5-year mortality. During the follow-up period, 133 (24.2%) patients experienced recurrent aspiration pneumonia. However, Kaplan-Meier analysis showed no significant differences in survival curves between patients with single and recurrent aspiration pneumonia (P = .371).

CONCLUSIONS/IMPLICATIONS

Long-term prognosis of aspiration pneumonia was poor as a result of underlying morbidity instead of the aspiration pneumonia itself. Our findings suggest that prognostic indices for patients with aspiration pneumonia including the patient's underlying conditions should be devised.

Proportion of Aspiration Pneumonia Cases Among Patients With Community-Acquired Pneumonia: A Single-Center Study in Korea

Objective

To investigate the proportion of aspiration pneumonia cases among patients with community-acquired pneumonia in Korea.

Methods

This retrospective study included patients with community-acquired pneumonia who had been admitted to the emergency department of a university-affiliated tertiary hospital in Gyeonggi Province, Korea between January 1, 2016 and December 31, 2016. Among these patients, those with aspiration pneumonia were identified using ICD-10 codes (J69.^*). Patients with recurrent pneumonia were excluded, as were those who were immunocompromised. The proportion of cases of aspiration pneumonia was calculated, and the characteristics and clinical outcomes of patients with aspiration pneumonia and non-aspiration pneumonia were compared.

Results

The proportion of aspiration pneumonia cases among patients with community-acquired pneumonia was 14.2%. Patients with aspiration pneumonia were significantly more likely to be older (p<0.001) and male (p<0.001), and to have a higher confusion, uremia, respiratory rate, blood pressure, and age ≥65 years (CURB-65) score (p<0.001) as compared to patients with non-aspiration pneumonia. They were also more likely to require admission to the intensive care unit (p<0.001) and a longer hospital stay (p<0.001).

Conclusion

Aspiration pneumonia accounts for 14.2% of all cases of community-acquired pneumonia in Korea. These data may contribute to the establishment of healthcare strategies for managing aspiration pneumonia among Korean adults.

Primary Pulmonary Acinic Cell Carcinoma: A Clinicopathological Study of 6 Cases and Literature Review

Primary pulmonary acinic cell carcinoma (ACC) is rare. The clinicopathological features are not identical to that of classic ACC that leads to misdiagnosis. In this article, we summarized the clinicopathological features of 25 such cases, including 6 cases in this series and additional 19 cases in the literature. Pulmonary ACCs showed an overwhelming solid growth pattern. The neoplastic cells had eosinophilic granular and clear cytoplasm in most cases and displayed basophilic cytoplasm in only 4 cases. Intratumoral fibrous septa, mitotic figure, necrosis, and psammoma bodies were observed in some cases. Prominent nuclear atypia and perineural invasion might suggest high-grade transformation, metastasis, and recurrence. The tumor cells were strongly positive for CK8/18 and negative for TTF-1, p63, S-100, mammaglobin, MUC5b, MUC5ac, and DOG1. CK7 was exclusively positive for neoplastic cells with ductal differentiation. Of the 25 included cases, 10 cases were initially misdiagnosed. The tumor was prone to involve the right bronchus. The patient outcome was favorable. The accurate diagnosis of primary pulmonary ACC relies on comprehensive evaluation of histological and immunohistochemical features and realization of the difference from classic ACC.

Respiratory mortality of childhood, adolescent and young adult cancer survivors

BACKGROUND

Exposure to radiation and/or chemotherapy during cancer treatment can compromise respiratory function. We investigated the risk of long-term respiratory mortality among 5-year cancer survivors diagnosed before age 40 years using the British Childhood Cancer Survivor Study (BCCSS) and Teenage and Young Adult Cancer Survivor Study (TYACSS).

METHODS

The BCCSS comprises 34 489 cancer survivors diagnosed before 15 years from 1940 to 2006 in Great Britain. The TYACSS includes 200 945 cancer survivors diagnosed between 15 years and 39 years from 1971 to 2006 in England and Wales. Standardised mortality ratios and absolute excess risks were used.

FINDINGS

Overall, 164 and 1079 respiratory deaths were observed in the BCCSS and TYACSS cohorts respectively, which was 6.8 (95% CI 5.8 to 7.9) and 1.7 (95% CI 1.6 to 1.8) times that expected, but the risks varied substantially by type of respiratory death. Greatest excess numbers of deaths were experienced after central nervous system (CNS) tumours in the BCCSS and after lung cancer, leukaemia, head and neck cancer and CNS tumours in the TYACSS. The excess number of respiratory deaths increased with increasing attained age, with seven (95% CI 2.4 to 11.3) excess deaths observed among those aged 50+ years in the BCCSS and three (95% CI 1.4 to 4.2) excess deaths observed among those aged 60+ years in the TYACSS. It was reassuring to see a decline in the excess number of respiratory deaths among those diagnosed more recently in both cohorts.

CONCLUSIONS

Prior to this study, there was almost nothing known about the risks of respiratory death after cancer diagnosed in young adulthood, and this study addresses this gap. These new findings will be useful for both survivors and those involved in their clinical management and follow-up.

Coordination of Pharyngeal and Laryngeal Swallowing Events During Single Liquid Swallows After Oral Endotracheal Intubation for Patients with Acute Respiratory Distress Syndrome

To evaluate timing and duration differences in airway protection and esophageal opening after oral intubation and mechanical ventilation for acute respiratory distress syndrome (ARDS) survivors versus age-matched healthy volunteers. Orally intubated adult (≥ 18 years old) patients receiving mechanical ventilation for ARDS were evaluated for swallowing impairments via a videofluoroscopic swallow study (VFSS) during usual care. Exclusion criteria were tracheostomy, neurological impairment, and head and neck cancer. Previously recruited healthy volunteers (n = 56) served as age-matched controls. All subjects were evaluated using 5-ml thin liquid barium boluses. VFSS recordings were reviewed frame-by-frame for the onsets of 9 pharyngeal and laryngeal events during swallowing. Eleven patients met inclusion criteria, with a median (interquartile range [IQR]) intubation duration of 14 (9, 16) days, and VFSSs completed a median of 5 (4, 13) days post-extubation. After arrival of the bolus in the pharynx, ARDS patients achieved maximum laryngeal closure a median (IQR) of 184 (158, 351) ms later than age-matched, healthy volunteers (p < 0.001) and it took longer to achieve laryngeal closure with a median (IQR) difference of 151 (103, 217) ms (p < 0.001), although there was no significant difference in duration of laryngeal closure. Pharyngoesophageal segment opening was a median (IQR) of - 116 (- 183, 1) ms (p = 0.004) shorter than in age-matched, healthy controls. Evaluation of swallowing physiology after oral endotracheal intubation in ARDS patients demonstrates slowed pharyngeal and laryngeal swallowing timing, suggesting swallow-related muscle weakness. These findings may highlight specific areas for further evaluation and potential therapeutic intervention to reduce post-extubation aspiration.

Pneumonitis and pneumonia after aspiration

Aspiration pneumonitis and aspiration pneumonia are clinical syndromes caused by aspiration. These conditions are clinically significant due to their high morbidity and mortality. However, aspiration as a preceding event are often unwitnessed, particularly in cases of asymptomatic or silent aspiration. Furthermore, despite the difference in treatment approaches for managing aspiration pneumonitis and aspiration pneumonia, these two disease entities are often difficult to discriminate from one another, resulting in inappropriate treatment. The use of unclear terminologies hinders the comparability among different studies, making it difficult to produce evidence-based conclusions and practical guidelines. We reviewed the most recent studies to define aspiration, aspiration pneumonitis, and aspiration pneumonia, and to further assess these conditions in terms of incidence and epidemiology, pathophysiology, risk factors, diagnosis, management and treatment, and prevention.

The Influence of pH Elevation on the Incidence of Nosocomial Pneumonia

Nosocomial pneumonia, one of the most common hos pital-acquired infectious diseases, is associated with sub stantial morbidity and mortality, approaching 50% in selected patients. Patients with alterations in their tracheobronchial tree or natural host-defense mecha nisms are at increased risk of developing pneumonia. Organisms gain access to the normally sterile tracheo bronchial tree primarily by aspiration of colonized oro pharyngeal gastric secretions. Risk factors for bacterial colonization and the development of nosocomial pneu monia include increased age, elevated pH of gastric con tents, postoperative state, nutritional status, severe underlying disease (for example, chronic obstructive pulmonary disease), administration of corticosteroids or other immunosuppressive therapy, and intubation or mechanical ventilation. High gastric volume may also increase the chance of aspiration of secretions in some high-risk patients.

Analytic Reviews : Aspiration Pneumonitis: Patient Risk Factors, Prevention, and Management

Occurrence of aspiration pneumonitis, the morbid con dition that often follows aspiration of gastric contents, has been documented for over 40 years. A number of risk factors that predispose patients to acid aspiration have been identified. The acidity of the gastric fluid and the volume of the aspirate are high-risk factors that de termine the severity of the pneumonitis. In this review I discuss those conditions that predispose patients to as piration and subsequent development of pneumonitis as well as current strategies for prevention and treatment.

Acute Respiratory Failure in Pregnancy

Acute respiratory failure in pregnancy has multiple etiologies, including thromboembolism, amniotic fluid embolism, venous air embolism, aspiration of gastric contents, respiratory infections, asthma, beta-adrenergic tocolytic therapy, and pneumomediastinum and pneu mothorax. Proper management of acute respiratory fail ure in pregnancy requires an understanding of the specific diseases and the normal gestational changes that occur in maternal respiration (decreased functional re sidual capacity, increased minute ventilation, mild respi ratory alkalosis) and hemodynamics (increased cardiac output, increased blood and plasma volume, unchanged central pressures). Knowledge of the determinants of oxygen delivery to fetal tissue (uterine blood flow, pla cental transfer, fetal circulation) and how they are af fected by changes in maternal hemodynamics, position, acid-base status, and medications can help sustain nor mal fetal development, whenever possible, without compromising maternal care. Diagnostic testing such as radiography, hemodynamic monitoring, and fetal moni toring are considered in terms of attendant risk to the mother or the fetus, alterations in normal values related to gestation, and indications for usage. Similarly, the risks and benefits of supportive and specific therapies for the various etiologies of acute respiratory therapy are reviewed.

Examining the evidence to guide practice: challenging practice habits

Nurses are the largest segment of the nation's health care workforce, which makes nurses vital to the translation of evidence-based practice as a practice norm. Critical care nurses are in a position to critically appraise and apply best evidence in daily practice to improve patients' outcomes. It is important for critical care nurses to continually evaluate their current practice to ensure that they are applying the current best evidence rather than practicing on the basis of tradition. This article is based on a presentation at the 2013 National Teaching Institute of the American Association of Critical-Care Nurses. Four practice interventions that are within the realm of nursing are critiqued on the basis of current best evidence: (1) turning critically ill patients, (2) sleep promotion in the intensive care unit, (3) feeding tube management in infants and children, and (4) prevention of venothromboembolism…again. The related beliefs, current evidence, and implications for practice associated with each topic are described.

Update on the pathogenesis and management of pneumonia in the elderly-roles of aspiration pneumonia

Pneumonia in the elderly results in the highest mortality among cases of community-acquired pneumonia (CAP). The pathophysiology of pneumonia in the elderly is primarily due to aspiration pneumonia (ASP). ASP comprises two pathological conditions: airspace infiltration with bacterial pathogens and dysphagia-associated miss-swallowing. The first-line therapy for the treatment of bacterial pneumonia in the elderly is a narrow spectrum of antibiotics, including sulbactam/ampicillin, which are effective against major lower respiratory infection pathogens and anaerobes. The bacterial pathogens of ASP cases of pneumonia in the elderly are similar to those associated with adult CAP. In addition to an appropriate course of antibiotics, pharmacologic and non-pharmacologic approaches for dysphagia and upper airway management are necessary for the treatment and prevention of pneumonia. Swallowing rehabilitation, oral health care, pneumococcal vaccination, gastroesophageal reflux management, and a head-up position during the night are necessary for the treatment and prevention of repeated episodes of pneumonia in elderly patients. In addition, tuberculosis should always be considered for the differential diagnosis of pneumonia in this patient population.

The bacterial pneumonias: a new treatment paradigm

Pneumonia is a common disease that carries a high mortality. Traditionally, pneumonia has been classified and treated according to the setting where the pneumonia develops, namely community-acquired pneumonia, health-care-associated pneumonia, and hospital-acquired pneumonia. This classification was based on the risk of a patient being infected with a hospital-acquired drug-resistant pathogen. A new treatment paradigm has been proposed based on the risk of the patient being infected with a community-acquired drug-resistant pathogen. The risk factors for infection with a community-acquired drug-resistant pathogen include (1) hospitalization for > 2 days during the previous 90 days, (2) antibiotic use during the previous 90 days, (3) nonambulatory status, (4) tube feeds, (5) immunocompromised status, (6) use of acid-suppressive therapy, (7) chronic hemodialysis during the preceding 30 days, (8) positive methicillin-resistant Staphylococcus aureus history within the previous 90 days, and (9) present hospitalization > 2 days. This article reviews this new treatment paradigm and other issues relevant to the diagnosis and management of pneumonia based on information from MEDLINE, EMBASE, and the Cochrane Register of Controlled Trials.

Aspiration pneumonia: a review of modern trends

PURPOSE

The purpose was to describe aspiration pneumonia in the context of other lung infections and aspiration syndromes and to distinguish between the main scenarios commonly implied when the terms aspiration or aspiration pneumonia are used. Finally, we aim to summarize current evidence surrounding the diagnosis, microbiology, treatment, risks, and prevention of aspiration pneumonia.

MATERIALS AND METHODS

Medline was searched from inception to November 2013. All descriptive or experimental studies that added to the understanding of aspiration pneumonia were reviewed. All studies that provided insight into the clinical aspiration syndromes, historical context, diagnosis, microbiology, risk factors, prevention, and treatment were summarized within the text.

RESULTS

Despite the original teaching, aspiration pneumonia is difficult to distinguish from other pneumonia syndromes. The microbiology of pneumonia after a macroaspiration has changed over the last 60 years from an anaerobic infection to one of aerobic and nosocomial bacteria. Successful antibiotic therapy has been achieved with several antibiotics. Various risks for aspiration have been described leading to several proposed preventative measures.

CONCLUSIONS

Aspiration pneumonia is a disease with a distinct pathophysiology. In the modern era, aspiration pneumonia is rarely solely an anaerobic infection. Antibiotic treatment is largely dependent on the clinical scenario. Several measures may help prevent aspiration pneumonia.

Interstitial pneumonitis after betadine aspiration

Disinfection of the face and mucosa lined surfaces of the nose and mouth using a povidone-iodine (PI) or Betadine solution is common practice among head and neck surgeons. Povidone-iodine, which is a highly effective broad-spectrum antibiotic effective against bacteria, viruses, fungi, and protozoa, decreases the risk of postoperative surgical wound infection. We report a case of PI aspiration causing an acute chemical pneumonitis after preoperative disinfection of the oral cavity and nasopharynx in preparation for cleft palate repair. As a result of the inflammatory response, the patient required positive pressure mechanical ventilation and a prolonged stay in the pediatric intensive care unit. The patient was safely extubated on hospital day 7 and discharged on hospital day 10 without any long-term sequelae on follow-up. We also review the 3 other reported cases of PI aspiration pneumonitis. Based on our case report and literature review, we conclude that PI aspiration is associated with a high rate of morbidity; however, this should not preclude the use of PI before surgery, given its effectiveness as an oral disinfectant and the exceedingly low incidence of aspiration.

Subglottic laryngeal closure: a unique modified method of laryngotracheal separation to prevent aspiration

OBJECTIVES

Laryngotracheal separation (LTS) is an ideal surgical method for intractable aspiration; however, the oral side of the tracheal stump can easily disintegrate. Therefore, we developed a modified LTS method. We performed subglottic laryngeal closure (SGLC) as a new surgical method and evaluated the outcomes.

METHODS

We retrospectively analyzed the medical records of 36 patients (28 male and 8 female; 15 to 91 years of age) who underwent SGLC between 2007 and 2011 at Tottori University Hospital, Japan. Operative data (operative time, intraoperative bleeding, and time to drain removal), outcomes (aspiration and changes in nutritional status), and complications with regard to the surgical method were examined. The occurrence of a subcutaneous proximal laryngeal stump fistula was evaluated by videofluoroscopy.

RESULTS

The SGLC was performed safely in all patients. Fistulization was observed in only 1 of the patients (2.8%), and major bleeding after surgery was observed in 1 patient (2.8%). The procedure relieved aspiration pneumonia in all patients.

CONCLUSIONS

We conclude that SGLC is effective for treating and preventing pulmonary aspiration. The incidence of postoperative complications, particularly that of subcutaneous fistulas, was very low. Therefore, this method may be useful for patients in poor condition.

Endothelial connexin43 mediates acid-induced increases in pulmonary microvascular permeability

Acid aspiration, a common cause of acute lung injury, leads to alveolar edema. Increase in lung vascular permeability underlies this pathology. To define mechanisms, isolated rat lungs were perfused with autologous blood. Hydrochloric acid and rhodamine-dextran 70 kDa (RDx70) were coinstilled into an alveolus by micropuncture. RDx70 fluorescence was used to establish the spatial distribution of acid. Subsequently, FITC-dextran 20 kDa (FDx20) was infused into microvessels for 60 min followed by a 10-min HEPES-buffered saline wash. During the infusion, FITC fluorescence changes were recorded to quantify the ratio of peak to postwash fluorescence. The ratio, termed normalized fluorescence, was low for acid compared with buffer instillation both in microvessels abutting acid-treated alveoli and those located more than 700 μm away. In contrast, the normalized fluorescence was similar to buffer controls when a higher molecular weight tracer (FITC-dextran 70 kDa) was infused instead of FDx20, suggesting that normalized FDx20 fluorescence faithfully represented microvascular permeability. Inhibiting endothelial connexin43 (Cx43) gap junction communication with Gap27 blunted the acid-induced reduction in normalized fluorescence, although scrambled Gap27 did not have any effect. The blunting was evident not only in microvessels away from the site of injury, but also in those abutting directly injured alveoli. Thus the new fluorescence-based method reveals that acid increases microvascular permeability both at acid-instilled and away sites. Inhibiting endothelial Cx43 blocked the permeability increase even at the direct injury sites. These data indicate for the first time that Cx43-dependent mechanisms mediate acid-induced increases in microvascular permeability. Cx43 may be a therapeutic target in acid injury.

Respiratory disease and the role of oral bacteria

The relationship between oral health and systemic conditions, including the association between poor oral hygiene, periodontal disease, and respiratory disease, has been increasingly debated over recent decades. A considerable number of hypotheses have sought to explain the possible role of oral bacteria in the pathogenesis of respiratory diseases, and some clinical and epidemiological studies have found results favoring such an association. This review discusses the effect of oral bacteria on respiratory disease, briefly introduces the putative biological mechanisms involved, and the main factors that could contribute to this relationship. It also describes the role of oral care for individuals who are vulnerable to respiratory infections.

[Swallowing disorders, pneumonia and respiratory tract infectious disease in the elderly]

Swallowing disorders (or dysphagia) are common in the elderly and their prevalence is often underestimated. They may result in serious complications including dehydration, malnutrition, airway obstruction, aspiration pneumonia (infectious process) or pneumonitis (chemical injury caused by the inhalation of sterile gastric contents). Moreover the repercussions of dysphagia are not only physical but also emotional and social, leading to depression, altered quality of life, and social isolation. While some changes in swallowing may be a natural result of aging, dysphagia in the elderly is mainly due to central nervous system diseases such as stroke, parkinsonism, dementia, medications, local oral and oesophageal factors. To be effective, management requires a multidisciplinary team approach and a careful assessment of the patient's oropharyngeal anatomy and physiology, medical and nutritional status, cognition, language and behaviour. Clinical evaluation can be completed by a videofluoroscopic study which enables observation of bolus movement and movements of the oral cavity, pharynx and larynx throughout the swallow. The treatment depends on the underlying cause, extent of dysphagia and prognosis. Various categories of treatment are available, including compensatory strategies (postural changes and dietary modification), direct or indirect therapy techniques (swallow manoeuvres, medication and surgical procedures).

Salivary gland surgery for control of chronic pulmonary aspiration in children with cerebral palsy

OBJECTIVE

To evaluate the outcome of surgical saliva reduction to decrease pulmonary aspiration in children with cerebral palsy and its repercussions in respiratory infection control.

METHODS

Twenty-nine children with neurological impairment and diagnosis of chronic pulmonary aspiration were submitted to bilateral submandibular gland excision and bilateral parotid duct ligation at the Association for the Welfare of Physically Handicapped Children, from December 2001 to December 2004. Postoperative frequency of lower respiratory tract infection, hospitalization rate due to pulmonary infection and airway secretion level after the surgery were compared to preoperative period.

RESULTS

Twenty-nine children with cerebral palsy aged 18 months to 9 years were submitted to submandibular glands excision and parotid ducts ligation. All children had gastrostomy and no oral intake. There were no major complications; two children had reopening of one parotid duct. Frequency of lower respiratory tract infections, rate of hospitalization for treatment of pulmonary infections and level of airway secretion were statistically reduced. Preoperative mean rate of lower respiratory tract infection was 6.9/year; in postoperative period, rate was 2.4/year (p<0.001). Pneumonia hospitalization mean rate was 63.4 days/year preoperatively and 17.5 days/year postoperatively (p<0.001). There was also a significant improvement in the need for suctioning of upper airway secretion (mean 11 times/day in preoperative period and 3.1 times/day in the postoperative period; p<0.001).

CONCLUSION

In children with cerebral palsy, surgical saliva reduction by submandibular glands excision and parotid ducts ligation is an effective and safe technique for frequency reduction of lower respiratory tract infection and level of airway secretion.