Salivary Amylase Level in Bronchoalveolar Fluid as a Marker of Chronic Pulmonary Aspiration in Children

Bronchoalveolar lavage (BAL) amylase and pepsin levels as potential biomarkers of aspiration pneumonia

BACKGROUND AND OBJECTIVE

There are currently no established markers for aspiration pneumonia. We hypothesized that bronchoalveolar lavage (BAL) amylase and pepsin might be candidate biomarkers for aspiration pneumonia.

METHODS

This cross-sectional study reviewed consenting adults who underwent clinically-indicated bronchoscopy at Aizu Medical Center. BAL samples were obtained using standardized methods. Amylase levels were measured in our clinical laboratory, and pepsin levels were assessed by ELISA.

RESULTS

Aspiration pneumonia was clinically diagnosed based on the guidelines of the Japanese Respiratory Society in 48 of the 327 participants. Median BAL salivary amylase and pepsin levels in this group were 702.0 U/L and 12.7 ng/ml respectively, which were significantly higher than in non-aspiration pneumonia patients. BAL amylase ≥204 U/L had 77.1% sensitivity and 84.2% specificity as a diagnostic index, and the area under the receiver operating characteristic (ROC) curve was 0.859 (95% confidence interval (CI), 0.803-0.915). Similarly, BAL pepsin levels of ≥7.45 ng/ml had 87.2% sensitivity and 59.9% specificity for identifying aspiration, and the area under the ROC curve was 0.757 (95% CI, 0.688-0.826). Multivariate regression demonstrated that BAL amylase ≥204 U/L and BAL pepsin ≥7.45 ng/ml were associated with significantly higher odds for aspiration pneumonia (odds ratio (OR) 10.0, 95% CI, 4.51-22.2, and OR 8.81 95% CI, 3.32-23.4, respectively). There were no significant associations between risk factors for aspiration pneumonia and BAL amylase and pepsin levels.

CONCLUSION

BAL amylase and pepsin might be useful biomarkers for suggesting aspiration pneumonia, and could be objective markers without relying on known risk factors for aspiration.

Neuromuscular electrical stimulation improves swallowing initiation in patients with post-stroke dysphagia

Objective

More than half of post-stroke patients develop dysphagia, which manifests as delayed swallowing and is associated with a high risk of aspiration. In this study, we aimed to investigate the immediate effect of neuromuscular electrical stimulation (NMES) on swallowing initiation in post-stroke patients using videofluoroscopic swallowing study (VFSS) data.

Materials and methods

This randomized, self-controlled crossover study included 35 patients with post-stroke dysphagia. All selected patients received real and sham NMES while swallowing 5 ml of thin liquid. Participants completed the conditions in random order, with a 10-min interval between conditions. The primary evaluation indicators included the Modified Barium Swallow Impairment Profile-6 (MBSImp-6) and Penetration-Aspiration Scale (PAS). Secondary indicators included oral transit time (OTT), pharyngeal transit time (PTT), and laryngeal closure duration (LCD).

Results

Modified Barium Swallow Impairment Profile-6 (P = 0.008) and PAS (P < 0.001) scores were significantly lower in the Real-NMES condition than in the Sham-NMES condition. OTT (P < 0.001) was also significantly shorter during Real-NMES than during Sham-NMES. However, LCD (P = 0.225) and PTT (P = 0.161) did not significantly differ between the two conditions.

Conclusion

Neuromuscular electrical stimulation may represent a supplementary approach for promoting early feeding training in patients with post-stroke dysphagia.

Clinical trial registration

[https://clinicaltrials.gov/], identifier [ChiCTR2100052464].

Research on Effects of Oropharyngeal Aspiration on Incidence of Ventilator-Associated Pneumonia in Patients with Cerebral Hemorrhage in ICU

Cerebral hemorrhage is a kind of intracranial hemorrhage caused by nontraumatic vascular rupture of the cerebral parenchyma, which is a common cerebrovascular disease with a high disability rate and mortality. This study aimed to explore the effects of oropharyngeal aspiration in reducing ventilator-associated pneumonia in patients with cerebral hemorrhage in ICU. In this study, 96 patients with cerebral hemorrhage were selected as the subjects. They received surgical treatment, and then they were transferred into ICU of Fourth Affiliated Hospital of Harbin Medical University from December 2019 to March 2020. The patients were randomly divided into intervention group and control group, with 48 in each group. The intervention group received periodic oropharyngeal aspiration, while the control group received routine nursing measures. After the intervention, the incidence of ventilator-associated pneumonia and the positive rate of amylase α-trachea cannula specimens were recorded and compared between the two groups. After the intervention, the incidence of ventilator-associated pneumonia was 14.89% in the intervention group and 39.58% in the control group, with a statistically significant difference. And, the α-amylase positive rate, mechanical ventilation time, and ICU care duration of endotrachea cannula specimens in the intervention group were significantly lower than those in the control group. In conclusion, oropharyngeal aspiration can effectively reduce the incidence of ventilator-associated pneumonia after cerebral hemorrhage and shorten mechanical ventilation and ICU care duration. It promotes the rehabilitation of patients.

Salivary C-Reactive Protein and Mean Platelet Volume in the Diagnosis and Follow-Up of Community-Acquired Pneumonia in Infants

Background: Community-acquired pneumonia (CAP) in infants is a major cause of morbidity and mortality, especially in developing countries. Increased salivary C-reactive protein (CRP) levels have been demonstrated in neonatal pneumonia and other diseases. We investigated the applicability of CRP and mean platelet volume (MPV) in the diagnosis and follow-up of CAP in infants. Methods: This prospective observational study included 45 infants admitted for CAP. We measured serum and salivary CRP levels via ELISA, while MPV was measured using an automated blood cell counter. Results: Both salivary and serum CRP values were significantly different in the studied population between admission and follow-up (P = 0.001 and P < 0.0001, respectively). The same was observed for MPV (P < 0.0001). We found significant positive correlations between serum and salivary CRP (r = 0.652, P < 0.0001) and between serum CRP and MPV (r = 0.495, P = 0.001), as well as between salivary CRP and MPV (r = 0.439, P = 0.003). Receiver operating curve analysis showed that salivary CRP at a cutoff value of 3.2 ng/L had a sensitivity of 97.2% and specificity of 90%, while MPV at a cutoff value of 8.4 fL showed 91% sensitivity and 90% specificity. Conclusions: The present study showed that both salivary CRP and MPV are reliable diagnostic markers of CAP in infants.

Is α-Amylase an Important Biomarker to Detect Aspiration of Oral Secretions in Ventilated Patients?

Alpha-amylase has emerged as a biomarker of interest in detecting aspiration of oral secretions. In several studies, most ventilated patients have α-amylase values detected in pulmonary secretions. Values of α-amylase are high (as expected) in oral secretions and lowest in bronchoalveolar lavage samples. Around 5-7% of oral α-amylase is detectable in tracheal secretions. Once secretions are aspirated, the duration of detection of α-amylase in pulmonary secretions is unknown. Evidence varies on the relationship between α-amylase and clinical outcomes. Although detection of α-amylase in pulmonary secretions is useful to identify that aspiration has occurred, the lack of standardized reference values, the lack of knowledge regarding duration of detection following aspiration, and mixed findings related to clinical outcomes, limit its usefulness as a measurement tool. If α-amylase is to be used in research and/or clinical practice, additional data are needed to assist in interpretation and application of findings.

Impact of deep oropharyngeal suctioning on microaspiration, ventilator events, and clinical outcomes: A randomized clinical trial

AIMS

To evaluate a deep oropharyngeal suction intervention (NO-ASPIRATE) in intubated patients on microaspiration, ventilator-associated events and clinical outcomes.

DESIGN

Prospective, two-group, single-blind, randomized clinical trial.

METHODS

The study was conducted between 2014 - 2017 in 513 participants enroled within 24 hr of intubation and randomized into NO-ASPIRATE or usual care groups. Standard oral care was provided to all participants every 4 hr and deep oropharyngeal suctioning was added to the NO-ASPIRATE group. Oral and tracheal specimens were obtained to quantify α-amylase as an aspiration biomarker.

RESULTS

Data were analysed for 410 study completers enrolled at least 36 hr: NO-ASPIRATE (N = 206) and usual care (N = 204). Percent of tracheal specimens positive for α-amylase, mean tracheal α-amylase levels over time and ventilator-associated events were not different between groups. The NO-ASPIRATE group had a shorter hospital length of stay and a subgroup with moderate aspiration at baseline had significantly lower α-amylase levels across time.

CONCLUSION

Hospital length of stay was shorter in the NO-ASPIRATE group and a subgroup of intervention participants had lower α-amylase across time. Delivery of standardized oral care to all participants may have been an intervention itself and possibly associated with the lack of significant findings for most outcomes.

IMPACT

This trial compared usual care to oral care with a deep suctioning intervention on microaspiration and ventilator-associated events, as this has not been systematically studied. Further research on the usefulness of α-amylase as an aspiration biomarker and the role of oral suctioning, especially for certain populations, is indicated.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov: NCT02284178.