The Implication of Preoperative Central Stenosis on Patient Reported Outcomes After Lumbar Decompression Surgery

OBJECTIVE

To assess the impact of central stenosis severity on patient-reported outcomes after lumbar decompression.

METHODS

Patient diagnosis, demographics, and surgical characteristics were collected via query search and manual chart review of electronic medical records. The inclusion criteria were posterior lumbar decompressions from 2014-2020, with accessible MRI reports. As previously validated by Lee et al., central stenosis was determined on magnetic resonance imaging and graded as none, mild, moderate, or severe. Patients were dichotomized into two groups to improve statistical power for comparisons: none or mild central stenosis and moderate or severe central stenosis. PROMs were compared between cohorts at one year postoperatively. Statistical significance was set at p < 0.05.

RESULTS

On bivariant analysis, no significant differences were noted between cohorts with regard to preoperative, one-year postoperative, and ΔPROMs. In addition, no significant difference in the number of patients attaining minimal clinically important difference (MCID) for each PROM was noted between cohorts. With the exception of MCS-12, all intragroup preoperative to postoperative PROMs indicated significant improvement (all p<0.05) after lumbar decompression surgery. Multivariate regression identified moderate or severe central canal stenosis as a significant independent predictor of improvement in VAS-back (estimate=-1.464, p=0.045).

CONCLUSION

We demonstrate that patients with moderate or severe central spinal stenosis may have more improvement in back pain than those with mild or no central stenosis after lumbar spine decompression surgery.

Microbial signatures in the lower airways of mechanically ventilated COVID-19 patients associated with poor clinical outcome

Respiratory failure is associated with increased mortality in COVID-19 patients. There are no validated lower airway biomarkers to predict clinical outcome. We investigated whether bacterial respiratory infections were associated with poor clinical outcome of COVID-19 in a prospective, observational cohort of 589 critically ill adults, all of whom required mechanical ventilation. For a subset of 142 patients who underwent bronchoscopy, we quantified SARS-CoV-2 viral load, analysed the lower respiratory tract microbiome using metagenomics and metatranscriptomics and profiled the host immune response. Acquisition of a hospital-acquired respiratory pathogen was not associated with fatal outcome. Poor clinical outcome was associated with lower airway enrichment with an oral commensal (Mycoplasma salivarium). Increased SARS-CoV-2 abundance, low anti-SARS-CoV-2 antibody response and a distinct host transcriptome profile of the lower airways were most predictive of mortality. Our data provide evidence that secondary respiratory infections do not drive mortality in COVID-19 and clinical management strategies should prioritize reducing viral replication and maximizing host responses to SARS-CoV-2.

Microbial signatures in the lower airways of mechanically ventilated COVID19 patients associated with poor clinical outcome.. [PMID: 33791687 PMCID: PMC8010736 DOI: 10.21203/rs.3.rs-266050/v1]

Mortality among patients with COVID-19 and respiratory failure is high and there are no known lower airway biomarkers that predict clinical outcome. We investigated whether bacterial respiratory infections and viral load were associated with poor clinical outcome and host immune tone. We obtained bacterial and fungal culture data from 589 critically ill subjects with COVID-19 requiring mechanical ventilation. On a subset of the subjects that underwent bronchoscopy, we also quantified SARS-CoV-2 viral load, analyzed the microbiome of the lower airways by metagenome and metatranscriptome analyses and profiled the host immune response. We found that isolation of a hospital-acquired respiratory pathogen was not associated with fatal outcome. However, poor clinical outcome was associated with enrichment of the lower airway microbiota with an oral commensal (Mycoplasma salivarium), while high SARS-CoV-2 viral burden, poor anti-SARS-CoV-2 antibody response, together with a unique host transcriptome profile of the lower airways were most predictive of mortality. Collectively, these data support the hypothesis that 1) the extent of viral infectivity drives mortality in severe COVID-19, and therefore 2) clinical management strategies targeting viral replication and host responses to SARS-CoV-2 should be prioritized.

Microbial signatures in the lower airways of mechanically ventilated COVID19 patients associated with poor clinical outcome

Mortality among patients with COVID-19 and respiratory failure is high and there are no known lower airway biomarkers that predict clinical outcome. We investigated whether bacterial respiratory infections and viral load were associated with poor clinical outcome and host immune tone. We obtained bacterial and fungal culture data from 589 critically ill subjects with COVID-19 requiring mechanical ventilation. On a subset of the subjects that underwent bronchoscopy, we also quantified SARS-CoV-2 viral load, analyzed the microbiome of the lower airways by metagenome and metatranscriptome analyses and profiled the host immune response. We found that isolation of a hospital-acquired respiratory pathogen was not associated with fatal outcome. However, poor clinical outcome was associated with enrichment of the lower airway microbiota with an oral commensal ( Mycoplasma salivarium ), while high SARS-CoV-2 viral burden, poor anti-SARS-CoV-2 antibody response, together with a unique host transcriptome profile of the lower airways were most predictive of mortality. Collectively, these data support the hypothesis that 1) the extent of viral infectivity drives mortality in severe COVID-19, and therefore 2) clinical management strategies targeting viral replication and host responses to SARS-CoV-2 should be prioritized.