New predictors of complications in carotid body tumor resection

OBJECTIVE

This study examined the relationship between two new variables, tumor distance to base of skull (DTBOS) and tumor volume, with complications of carotid body tumor (CBT) resection, including bleeding and cranial nerve injury.

METHODS

Patients who underwent CBT resection between 2004 and 2014 were studied using a standardized, multi-institutional database. Demographic, perioperative, and outcomes data were collected. CBT measurements were determined from computed tomography, magnetic resonance imaging, and ultrasound examination.

RESULTS

There were 356 CBTs resected in 332 patients (mean age, 51 years; 72% female); 32% were classified as Shamblin I, 43% as Shamblin II, and 23% as Shamblin III. The mean DTBOS was 3.3 cm (standard deviation [SD], 2.1; range, 0-10), and the mean tumor volume was 209.7 cm³ (SD, 266.7; range, 1.1-1642.0 cm³). The mean estimated blood loss (EBL) was 257 mL (SD, 426; range, 0-3500 mL). Twenty-four percent of patients had cranial nerve injuries. The most common cranial nerves injured were the hypoglossal (10%), vagus (11%), and superior laryngeal (5%) nerves. Both Shamblin grade and DTBOS were statistically significantly correlated with EBL of surgery and cranial nerve injuries, whereas tumor volume was statistically significantly correlated with EBL. The logistic model for predicting blood loss and cranial nerve injury with all three variables-Shamblin, DTBOS, and volume (R² = 0.171, 0.221, respectively)-was superior to a model with Shamblin alone (R² = 0.043, 0.091, respectively). After adjusting for Shamblin grade and volume, every 1-cm decrease in DTBOS was associated with 1.8 times increase in risk of >250 mL of blood loss (95% confidence interval, 1.25-2.55) and 1.5 times increased risk of cranial nerve injury (95% confidence interval, 1.19-1.92).

CONCLUSIONS

This large study of CBTs demonstrates the value of preoperatively determining tumor dimensions and how far the tumor is located from the base of the skull. DTBOS and tumor volume, when used in combination with the Shamblin grade, better predict bleeding and cranial nerve injury risk. Furthermore, surgical resection before expansion toward the base of the skull reduces complications as every 1-cm decrease in the distance to the skull base results in 1.8 times increase in >250 mL of blood loss and 1.5 times increased risk of cranial nerve injury.

A systematic review of assessment of skill acquisition and operative competency in vascular surgical training

OBJECTIVE

The aim of this systematic review is to describe the literature and assessment tools evaluating vascular surgical operative performance that could potentially be used for the assessment of educational outcomes applicable to the Milestone Project and the Next Accreditation System.

METHODS

A systematic review of PubMed/MEDLINE, EMBASE, PsycINFO, and key journals from 1985 to 2013 was performed to identify English-language articles describing assessment of vascular surgical skills and competence. Qualifying studies were abstracted for data concerning study aims, study and assessment setting, skills measured, and metrics used to determine competency. Strengths, weaknesses, and psychometric robustness of the assessment tools were determined.

RESULTS

The literature search identified 617 citations. After title and abstract review, 65 articles were retrieved for full-text assessment and 48 articles were included in the final review. Twenty-nine articles assessed open vascular skills; 19, endovascular skills; six, nontechnical skills; and one, teamwork skills. The majority (84%) of studies were performed in a simulated environment, four (8%) were performed in the operating room, and the remaining three were performed in both a simulated environment and an operating room. Strengths and weaknesses of assessment tools were study and assessor dependent, with none applicable to all study scenarios or procedures.

CONCLUSIONS

The literature describing assessment tools pertinent to vascular surgery is diverse. Existing assessment tools may be relevant to individual technical skill acquisition assessment; however, an operative assessment tool relevant to vascular/endovascular surgery and generalizable to the wide spectrum of technical and nontechnical skills pertinent to vascular surgery needs to be developed, validated, and implemented to allow the practical assessment of resident readiness to operate in an unsupervised setting.