Statistical prediction of the type of gastric aspiration lung injury based on early cytokine/chemokine profiles.

BACKGROUND: Unwitnessed gastric aspiration can be a diagnostic dilemma, and early discrimination of different forms may help to identify individuals with increased risk of development of severe clinical acute lung injury or acute respiratory distress syndrome. The authors hypothesized that inflammatory mediator profiles could be used to help diagnose different types of gastric aspiration. METHODS: Diagnostic modeling using a newly modified receiver operator characteristic approach was applied to recently published data from our laboratory on lavaged inflammatory mediators from rodents given intratracheal normal saline, hydrochloric acid, small nonacidified gastric particles, or a combination of acid and small gastric particles. Multiple animal groups and postaspiration times of injury were analyzed to gauge the applicability of the predictive approach: rats (6 and 24 h), C57/BL6 wild-type mice (5 and 24 h), and transgenic mice on the same background deficient in the gene for monocyte chemoattractant protein 1 (MCP-1 [-/-] mice; 5 and 24 h). RESULTS: Overall, the four types of aspiration were correctly discriminated in 85 of 96 rats (89%), 72 of 78 wild-type mice (92%), and 59 of 73 MCP-1 (-/-) mice (81%) by models that used a maximum of only two mediators. The severe "two-hit" aspirate of the combination of acid and small gastric particles was correctly predicted in 21 of 24 rats, 23 of 23 wild-type mice, and 21 of 21 MCP-1 (-/-) mice. Specific best-fit mediators or mediator pairs varied with aspirate type, animal type, and time of injury. Cytokines and chemokines that best predicted the combination of acid and small gastric particles were cytokine-induced neutrophil chemoattractant 1 (6 h) and MCP-1 (24 h) in rats, tumor necrosis factor alpha/macrophage inflammatory protein 2 (5 h) and tumor necrosis factor alpha/MCP-1 (24 h) in wild-type mice, and tumor necrosis factor alpha/macrophage inflammatory protein 2 (5 h) and tumor necrosis factor alpha/keratinocyte-derived cytokine (24 h) in MCP-1 (-/-) mice. CONCLUSIONS: These results support the potential feasibility of developing predictive models that use focused measurements of inflammatory mediators to help diagnose severe clinical forms of unwitnessed gastric aspiration, such as the combination of acid and small gastric particles, that may have a high risk of progression to acute lung injury/acute respiratory distress syndrome.

Effect of professional oral health care on the elderly living in nursing homes.

OBJECTIVE: We evaluated the effectiveness of professional oral health care (POHC) given by dental hygienists once a week for 24 months to 141 elderly persons needing daily care and living in 2 nursing homes. STUDY DESIGN: Elderly subjects with POHC and without POHC living in 2 nursing homes were examined for 24 months to detect any fevers of 37.8 degrees C or more and the prevalence of fatal aspiration pneumonia. The numbers of Staphylococcus species and Candida albicans in swab samples from oral cavities were compared between the POHC group and the non-POHC group. The amounts of methylmercaptan exhaled in the POHC group were determined and compared with those in the non-POHC group. RESULTS: The prevalence of fevers of 37.8 degrees C or more in the subjects receiving POHC was significantly lower than in the non-POHC group (P < .05). We found that the ratio of fatal aspiration pneumonia in the POHC group during the 24 months was significantly lower than in the non-POHC group (P < .05). Numbers of C albicans species in samples obtained from the oral cavity after 6 months of POHC were significantly lower than those in the non-POHC group (P < .01). POHC resulted in the reduction of the presence of Staphylococcus but not to a statistically significant extent. The amounts of methylmercaptan exhaled by the POHC group were significantly less than those of the non-POHC group (P <.05). CONCLUSION: This study showed that POHC administered by dental hygienists to a group of elderly patients needing daily nursing care was associated with a reduction in prevalence of fever and fatal pneumonia.

Trends in postneonatal aspiration deaths and reclassification of sudden infant death syndrome: impact of the "Back to Sleep" program.

OBJECTIVE: The introduction of the "Back to Sleep" campaign for the prevention of sudden infant death syndrome (SIDS) brought with it concern that there might be an increase in the incidence of aspiration-related deaths. The objective of this analysis was to describe the trends in postneonatal mortality and proportionate mortality ratios for the United States for the years 1991 to 1996 for aspiration-related deaths and other causes to which a SIDS death could conceivably be reclassified. METHODS: Linked birth and infant death vital statistic files for the United States were used for the years 1991, 1995, and 1996. US Vital Statistic Mortality files for the years 1992, 1993, and 1994 were used because of the absence of linked files for those years. RESULTS: The overall postneonatal mortality rate between 1991 and 1996 declined 21.9%, whereas the SIDS rate declined 38.9%. The proportion of the postneonatal mortality (PNPMR) contributed by SIDS declined from 37.1% in 1991 to 28.8% in 1996. There was no significant increase in the PNPMR for aspiration, asphyxia, or respiratory failure. There was, however, a significant increase in the PNPMR for suffocation in bed or cradle from 0.9 to 1.3. CONCLUSIONS: These data show no evidence of an increased risk of death from aspiration as a result of the "Back to Sleep" program. Although there has been an increase in the proportion of postneonatal mortality attributable to suffocation, this represents a very small proportion of postneonatal mortality and thus potentially a very small number of SIDS deaths reclassified as suffocation.

[Proposal for a predictive clinical scale in dysphagia]. / Proposition d'une échelle clinique prédictive du risque de fausses-routes.

The compiling of a predictive clinical scoring system for the risk of a false passage (FP) has its origins in the limitations of tests which explore only the cough reflex, known to be absent or faulty in 40% of patients investigated for problems of deglutition. A raised clinical score is based on the results of an exhaustive prospective study of 140 patients tested for the first time by videofluoroscopy for FP, this being the reference investigation for false passages. Discriminant analysis allowed the most selective variables to be identified and retained. We have identified 2 categories of patients, according to whether or not they have had any ENT past history. The score is obtained by adding the weighted values for the selected clinical signs. For those patients with an ENT past history, 5 clinical variables were retained: the absence of adhesions = 14, the presence of a velar reflex = 8, the capacity for voluntary deglutition = 8, glottic obstruction = 6, the absence of primitive reflexes = 6, giving a total score for the variables of between 0 and 42. If the total exceeds 32 or is less than 26, there is no FP; for scores between 32 and 26, videofluoroscopy is required to give more precise evidence of the risk. When this scoring system was applied prospectively to a series of 105 patients, a correct predictive result was obtained in 54 patients (51.4%), an equivocal result in 42 patients (40%), and a false result in 9 patients (8.6%), 3 of which (2.8%) were false negatives. The predictive score for FP allows evaluation of the risks of FP in at-risk patients, and adaptation of the treatment strategy according to the type of disordered physiology expected from the cause; thus videofluoroscopy can then be reserved for cases where treatment fails, so that the precise deglutition problem can be pinpointed.

[Analysis and radiologic staging of the type and severity of aspiration]. / Analyse und radiologisches Staging des Typs und Schweregrades einer Aspiration.

The estimated number of the incidence of undiagnosed chronic aspiration pneumonia after cerebral or cerebrovascular injury seems very high. According to American statistics, at least 6% of these patients die from aspiration pneumonia within the first year. The high temporal resolution of cineradiography with frame rates of the complex process of pharyngeal swallowing lasting 0.7 s. The method enables us to differentiate between so-called pre-, intra- and postdeglutitive aspiration, which means aspiration before, during and after the triggering of the swallowing reflex. Together with an established score for the severeness of the aspiration, the method supplies important data for setting up a functional surgical and/or conservative program for rehabilitation and for follow-up-studies.

Dysphagia following various degrees of surgical resection for oral cancer.

Postoperative swallowing problems were investigated in 20 patients who had undergone various degrees of surgical resection for oral cancer. The swallowing problems were evaluated on the basis of type of food, degree of aspiration, and duration of postoperative nasogastric tube feeding. Two patients with tongue cancer who had had hemiglossectomy without reconstruction ate normal food without aspiration within a week after operation. Eight patients who had undergone two- to three-quarter glossectomy for tongue cancer ate gruel with no or occasional liquid aspiration. Among 4 patients who had had near-total or total glossectomy for tongue cancer, 3 ate thin gruel or liquid with occasional aspiration. The other could not eat orally because of consistent severe aspiration. One patient with mouth floor cancer underwent resection of the mouth floor in combination with hemiglossectomy and she ate gruel without aspiration. Among 5 patients with mouth floor cancer who had had surgical removal accompanied by near-total or total glossectomy, 3 ate gruel with no or occasional liquid aspiration, 1 ate thin gruel with no aspiration, and the other could not eat orally. A diagnosis of T4 lesions, extensive removal of the tongue base, removal of the geniohyoid and mylohyoid muscles, and removal of the lateral pharyngeal wall were significantly related to poor swallowing function.

Aspiration pneumonitis: predisposing conditions and prevention.

Aspiration pneumonitis is a common complication of general anesthesia. The lower the pH of gastric fluid and/or the larger the volume, the greater is the potential danger. In spite of preoperative fasting, an alarmingly high percentage of patients who undergo surgery may be at risk. This review discusses conditions that predispose to aspiration pneumonitis and examines current strategies for its prevention.