Faculty Bibliography

BACKGROUND AND OBJECTIVES: Nourishing a child undergoing bone marrow transplant (BMT) is essential, but the optimal method to achieve this is not established. The objectives of the study were to investigate the incidence and risk factors for complications of gastrostomy tubes in patients with BMT. METHODS: A retrospective chart review was conducted of pediatric patients who received a percutaneous endoscopic gastrostomy (PEG) either for BMT or for other indications during a 3-year period. Occurrences of complications, absolute neutrophil count (ANC) at time of PEG placement, and ANC at time of complication were reviewed for both BMT and the comparison group. RESULTS: Of the 11 subjects in the BMT group, 4 (36%) had a major complication of infection related to PEG and 3 of those required PEG removal. Two of the 4 subjects who developed a major complication were moderately neutropenic at the time of PEG placement and all subjects were neutropenic at the time of complication. Of the 30 subjects in the comparison group, only 1 (2.8%) had a major complication with cellulitis. There were no statistically significant differences between the 2 groups before PEG placement for age, weight, albumin, or white blood cell count. The incidence of complication in BMT compared with the comparison group was significant (P=0.01). CONCLUSIONS: Our findings support that ANC should be considered before placement of PEG, significant neutropenia may be a contraindication for PEG placement in BMT patients, and other modalities for nutrition support might need to be considered.

OBJECTIVES: To evaluate and categorize the locations of missed parathyroid glands found during reoperative parathyroidectomy and to determine any factors associated with these locations. DESIGN: Retrospective cohort study. SETTING: Tertiary referral center. PATIENTS: Fifty-four patients who underwent reoperative parathyroidectomy for persistent or recurrent hyperparathyroidism from January 1, 2005, through January 1, 2009. MAIN OUTCOME MEASURES: Location of missed parathyroid glands and their association with continuous variables were analyzed using a Kruskal-Wallis test, and associations between gland location and categorical variables were evaluated using the Fisher exact test. RESULTS: Among 54 patients, 50 abnormal parathyroid glands were identified, resected, and classified as follows: 5 (10%) were type A (adherent to the posterior thyroid capsule); 11 (22%), type B (behind the thyroid in the tracheoesophageal groove); 7 (14%), type C (close to the clavicle in the prevertebral space); 3 (6%), type D (directly over the recurrent laryngeal nerve); 9 (18%), type E (easy to identify; near the inferior thyroid pole); 13 (26%), type F (fallen into the thymus); and 2 (4%), type G (gauche, within the thyroid gland). No demographic, biochemical, or pathological factors were significantly associated with gland location. Among the 43 patients followed up for 6 months, 40 (93%) had documented cures. CONCLUSIONS: Missed glands after parathyroidectomy for hyperparathyroidism can be found in standard locations in most cases. A standardized nomenclature system based on the regional anatomy and the embryology of the parathyroid glands can guide a systematic exploration for parathyroid adenomas that are not easily identified and facilitate communication about gland locations.

BACKGROUND: Elderly patients with primary hyperparathyroidism (PHPT) are often not referred for surgical intervention because of concern of comorbid conditions that may increase perioperative complications. Because PHPT is more common in the elderly, we sought to compare indications and complications of minimally invasive parathyroidectomy in patients 70 years of age and older (elderly) with their younger counterparts. STUDY DESIGN: A review was conducted of a prospectively collected database of all patients undergoing parathyroidectomy on our endocrine surgery service. Data collected included patient demographic, biochemical pathologic, and operative findings. Wilcoxon rank sum and chi-square tests were used for comparisons. RESULTS: Three hundred eighty-eight patients with PHPT recently underwent parathyroidectomy over a 3-year period (elderly, n=101; younger, n=287). The elderly cohort had significantly higher median preoperative creatinine (elderly, 2.0 mg/dL; younger,1.0 mg/dL; p=0.002) and parathyroid hormone (elderly, 145 pg/mL; younger, 123 pg/mL; p=0.026) levels. The elderly cohort also had more severe osteoporosis, with a significantly worse median bone mineral density T-score (elderly, -2.5; younger, -1.8; p<0.001). The rate of postoperative complications was similarly low in both groups (elderly, 5.9%; younger, 3.5%; p=0.38). CONCLUSIONS: Minimally invasive parathyroidectomy for PHPT can be performed as safely in elderly patients as in their younger counterparts. Elderly patients with PHPT are more likely to have osteoporosis and higher creatinine levels at the time of surgical referral. Additional study of the role of earlier intervention is warranted.

OBJECTIVE: Posterior retroperitoneoscopic adrenalectomy (PRA) is a minimally invasive approach to removal of the adrenal gland. This anatomically direct approach, popularized by Walz, minimizes dissection and affords early access to the adrenal vein. We report the largest experience to date of PRA in the United States. METHODS: The prospective endocrine surgery database at a tertiary care center was used to capture all patients who underwent PRA between October 2005 and February 2008. All PRA procedures were performed using a 3-trocar technique with the patient in a prone jackknife position. RESULTS: Sixty-eight PRAs were performed in 62 patients; there were 6 conversions (3 video-assisted and 3 open). Indications for adrenalectomy were functional tumors in 43 patients (20 pheochromocytomas, 13 Cushing disease or syndrome, and 10 others), nonfunctional cortical adenomas in 4, and isolated adrenal metastases in 15. Mean tumor size was 3.4 cm. Complications occurred in 11 patients (16%), with no perioperative deaths. In 34 (55%) patients, there was a relative contraindication to an anterior approach. Additionally, 20 patients (38%) had a body mass index greater than 30. Median operating time was 121 minutes. CONCLUSION: PRA is safe, avoids intra-abdominal adjacent organ mobilization, is unaffected by the presence of intra-abdominal adhesions, and is possible in obese patients. PRA may be the preferred technique for removing benign adrenal tumors and isolated metastases.

BACKGROUND: Parathyroid cryopreservation is used for potential autografting in patients who are rendered hypocalcemic following surgery. Cryopreservation employs multiple resources and carries a significant cost for processing and storage of tissue. Importantly, the length of time that parathyroid tissue remains functional after cryopreservation is not known. The goal of our study was to assess ex-vivo viability of parathyroid tissue in relation to the length of time in storage. We sought to define the appropriate time frame for tissue utilization and disposal to assist with long-term surgical planning. METHODS: From 1991 to 2006, 501 parathyroid specimens from 149 patients were cryopreserved at -80 degrees C according to standardized techniques. A single trained technician assessed viability, using a hemacytometer to count viable (clear cell) and nonviable (blue cell) tissue. Univariate analysis was performed to correlate length of preservation, diagnosis with viability. RESULTS: We evaluated 106 random parathyroid specimens. Samples were divided into two groups: those stored>24 months and those stored24 months (p<0.001). CONCLUSIONS: Viability of cryopreserved parathyroid cells is associated with duration of storage. Parathyroids preserved for greater than 24 months are unlikely to be viable. It seems reasonable to limit parathyroid cryopreservation to 24 months when frozen at -80 degrees C. Further studies are needed to optimize the process of cryopreservation to enhance cell viability.