Does Pathogen Identification Influence the Clinical Outcomes in Patients With Pyogenic Spinal Infections?

STUDY DESIGN: Retrospective study. OBJECTIVE: To study the clinical outcomes of patients suffering from pyogenic spinal infections (PSI), by comparing the outcomes of patients with an identified microbiological agent with those of patients without an identified pathogen. SUMMARY OF BACKGROUND DATA: PSI is associated with significant risks for morbidity and mortality. Specific antibiotic treatment has been considered a key to successful medical treatment; however, clinicians frequently treat patients with PSI without an identified agent. A paucity of data is available comparing the clinical outcomes of patients with or without an identified pathogen. MATERIALS AND METHODS: The records of 97 consecutive patients discharged from a University Hospital with the diagnosis of PSI during a 14-year period were retrospectively reviewed. Patients' demographics, etiological agent, comorbidities, site of infection, white blood cell count, erythrocyte sedimentation rate, C-reactive protein at the time of presentation, neurological impairment, length of hospital stay, and mortality were registered to compare the clinical outcomes of patients with an identified pathogen with those of patients without an identified agent. RESULTS: The causative organism was identified in 74 patients (76.3%). Patients with microbiological diagnosis were younger, and a larger percentage of them exhibited elevated C-reactive protein value; however, they were not different from those without an identified agent in terms of sex, site of infection, comorbidities, and the presence of a concomitant infection. Our study could not demonstrate different neurological outcomes, length of stay, or mortality rates among the 2 groups. CONCLUSIONS: In a large series of patients with PSI, we did not demonstrate differences in clinical outcomes using empirical antibiotics in patients without an identified pathogen compared with patients with an identified microbiological agent receiving specific antibiotics. Future prospective multicenter studies should be conducted to obtain an answer to this important clinical question.

An assessment of the Surgical Apgar Score in spine surgery.

BACKGROUND CONTEXT: The Surgical Apgar Score (SAS), a simple metric based on intraoperative heart rate, blood pressure, and blood loss, was developed in general and vascular surgery to predict 30-day major postoperative complications and mortality. No validation of SAS has been performed in spine surgery. PURPOSE: To perform a prospective assessment of SAS in spine surgery. STUDY DESIGN: Prospective study. PATIENT SAMPLE: Two hundred sixty-eight consecutive patients undergoing major and intermediate spinal surgeries in an 18-month period. OUTCOME MEASURES: Occurrence of major complications or death within 30 days of surgery. METHODS: Intraoperative parameters were registered, and SAS was calculated immediately after surgery. Outcome data were collected during a 30-day follow-up. The relationship between SAS and the outcomes was analyzed calculating relative risks (RRs) and likelihood ratios (LRs) for different scoring groups. A univariate logistic regression analysis was also performed. The discriminatory accuracy of SAS was evaluated calculating a C-statistic. RESULTS: Eighteen patients had ≥1 complications (6.72%). Patients with SAS 9-10 exhibited a 1.64% complication rate (RR=1; LR=0.23), which monotonically augmented as the score decreased: (SAS 7-8=2.75%; RR=1.68; LR=0.39), (SAS 5-6=13.33%; RR=8.13; LR=2.14), (SAS≤4=17.39%; RR=10.61; LR=2.92). The regression analysis odds ratio was 0.66 (95% confidence interval, 0.54-0.82), p<.01. The C-statistic was 0.77 (95% confidence interval, 0.66-0.88). CONCLUSIONS: Surgical Apgar Score allows risk stratification and has a good discriminatory power in patients undergoing spine surgery.

The Spine Instability Neoplastic Score: an independent reliability and reproducibility analysis.

BACKGROUND: Metastatic vertebral instability has not yet been clearly defined in the literature; there still exists a paucity of reliable criteria to assess the risk of vertebral collapse. PURPOSE: We performed an independent interobserver and intraobserver agreement evaluation of the Spine Instability Neoplastic Score (SINS) and correlated the score with selected clinical cases and the treatment they received. STUDY DESIGN: Independent reliability study for the newly created SINS. PATIENT SAMPLE: Thirty patients who underwent either radiotherapy alone or surgery followed by radiotherapy were randomly selected from the orthopedic surgery and radiotherapy department's databases. OUTCOME MEASURES: Patients were rated and classified for spinal stability using SINS. Intraclass correlation coefficient (ICC) and Fleiss's kappa measures were occupied for reliability analysis. METHODS: Patients who underwent either radiotherapy alone or surgery followed by radiotherapy were randomly selected and classified for spinal stability using the SINS by orthopedic surgeons and nonorthopedic oncology specialists. ICC and Fleiss's kappa were calculated for inter- and intraobserver agreement. A comparative analysis of SINS and the actual management was also conducted. RESULTS: Interobserver ICC reliability for the SINS was 0.79; κ values for location, pain, bone quality, alignment, vertebral body collapse, and posterolateral involvement were 0.81, 0.58, 0.21, 0.45, 0.42, and 0.29 respectively. Intraobserver ICC for the SINS scores was 0.96; ICC values for the same components were 0.98, 0.98, 0.87, 0.88, 0.92, and 0.86, respectively. Potentially unstable lesions (SINS score≥7) were operated on in 62.5%. CONCLUSIONS: SINS seem to be a reproducible tool that could be used equally by multiple specialists to estimate metastatic vertebral stability; however, prospective clinical validation is still pending.

Can the Surgical Apgar Score predict morbidity and mortality in general orthopaedic surgery?

PURPOSE: The Surgical Apgar Score (SAS) is a simple tally based on intra-operative heart rate, blood pressure and blood loss; it predicts 30-day major postoperative complications and mortality in different surgical fields, but no validation has been performed in general orthopaedic surgery. METHODS: A prospective assessment of the SAS in 723 consecutive patients undergoing major and intermediate orthopaedic procedures was performed in an 18-month period. The SAS was calculated immediately after surgery, and the occurrence of major complications or death was registered within a 30-day follow-up. RESULTS: Thirty-seven patients had ≥1 complication (5.12 %). The complication rate did not augment as the score decreased (SAS 9-10 = 6.56 %; SAS 7-8 = 2.62 %; SAS 5-6 = 7.21 %; SAS ≤4 = 10.2 %), the relative risk did not augment as the score decreased and the likelihood ratio did not increase with decreasing SAS values, except in the subgroup of patients undergoing spine surgery. The C-statistic was 0.59 (95 % confidence interval 0.48-0.69), a weak discriminatory value. Using a threshold of 7 to define high-risk and low-risk patients, the SAS allowed risk stratification only for spine surgery. CONCLUSIONS: The SAS does not predict 30-day major complications and death in patients undergoing general orthopaedic surgery, but it is useful in the subgroup of patients undergoing spine surgery.