Risk factors for pulmonary complications after spine surgery

ABSTRACT

 

Study design: Registry study with prospectively collected data

Objective: To determine risk factors for pulmonary complications in spine surgery.

Methods: The Spine End Results Registry 2003–2004 is an exhaustive database of 1,592 patients who underwent spine surgery at the University of Washington Medical Center or Harborview Medical Center. Detailed information regarding patient demographic, medical comorbidity, and comorbidities, surgical invasiveness and adverse outcomes were prospectively recorded. The primary outcome measure was the occurrence of a pulmonary complication following surgery. Univariate relative risks and 95 % confidence intervals for each of the risk factors were determined. Multivariate log binomial regression analysis was performed to investigate the association between each risk factor and a pulmonary complication, while controlling for other important risk factors.

Results: Altogether, there were 199 pulmonary complications after spine surgery. The cumulative incidence of a respiratory complication after spine surgery was 9 % (144 patients). Multivariate analysis suggested gender, chronic obstructive pulmonary disease, congestive heart failure, diabetes, age, diagnosis, surgical invasiveness and surgery in the thoracic spine are significant risk factors for pulmonary complications after spinal surgery.

Conclusions: The results of the present study suggest numerous statistically significant risk factors for pulmonary complications after spine surgery. These results may aid the clinician with preoperative risk stratification and patient counseling.

STUDY RATIONALE While multiple studies have examined complication rates after spinal surgery, few studies have focused on risk factors for pulmonary complications after spine surgery. The rates of pulmonary complications after spine surgery has been reported to range from 0.9 % to 5 %, but methodology and definitions vary from study to study 1, 2, 3, 4. OBJECTIVE The objective of this study is to identify risk factors for pulmonary complications after spine surgery.

REFERENCES

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EDITORIAL STAFF PERSPECTIVE

This is an excellent study regarding complications in spine surgery. We are unaware of a similar undertaking. Of course an interesting follow-up study would be to see if any specific care measures that have been changed by the investigators have reduced the incidence of pulmonary complications. This would require a prospective follow-up study.

The other point not directly addressed in this study is the influence of antibiotics, application of a standardized postoperative respiratory care protocol for known at-risk patients, and intraoperative anesthesiologic management of patients. For instance, presence of intraoperative hypotension, requiring resuscitation, the number of blood transfusions, fresh frozen plasma or colloids as well as type and duration of intravenous antibiotic prophylaxis may be variables to consider. These are variables which usually can not readily be gathered from a retrospective study.

 The value of a study like this, is that a potentially underestimated clinical problem can now be studied prospectively in a more detailed fashion. No doubt this study advances our awareness of pulmonary problems and more invasive spine surgery in an ill population.