Use of tissue expanders and pre-operative external beam radiotherapy in the treatment of retroperitoneal sarcoma.

INTRODUCTION: We report our experience of treating retroperitoneal sarcoma (RPS) using pre-operative external beam radiotherapy (EBRT) in combination with radical resectional surgery from 1990 to 2005. METHODS: Twenty-eight primary and 10 recurrent tumors were identified from a prospective database. RESULTS: The resection rate was 71% overall; 82% in primary (23/28) and 40% (4/10) in recurrent cases. EBRT was administered preoperatively in 25 patients, postoperatively in 1, and palliatively in 11. In 33 patients a saline-filled tissue expander was inserted into the abdomen before radiotherapy to displace small bowel from the radiation field. 4,500-5,000 cGy was administered in fractions of 180-200 cGy over a 5-week period; surgery followed 6-8 weeks later. Expander insertion was associated with minimal morbidity; 31/37 patients received a dose of 4,000 cGy or more (median 4,650 cGy). Median resected tumor diameter was 13 cm, and a median of three adjacent organs was resected per patient. Complete macroscopic resection was achieved in 25/27 patients (93%); R0 in 9 (33%) and R1 in 13 (48%) (microscopic margins unclear in 5). There was no postoperative mortality. Tumors were high-grade in 20 patients, low-grade in 14 and ungraded in 4. Actuarial 5- and 10-year survival for all patients was 74 and 60%. For operable primary tumors, the 5-year survival and disease-free rates were 90 and 80%. In four patients with operable recurrent tumors, median disease-free interval was 91 months (27-160). In the 11 inoperable cases, median survival after radiotherapy was 48 months (9-77). CONCLUSIONS: We conclude that a combination of pre-operative tissue expander placement, high-dose EBRT and radical resectional surgery can achieve acceptable morbidity, extended survival and low long-term recurrence in patients with RPS. STATISTICS: Median (interquartile range).

The effect of moderate levels of simulated altitude on sustained cognitive performance.

Previous work has documented cognitive deficits at high altitudes (15,000-25,000 ft), but there is controversy for lower altitudes. This study looked at the effects of moderate altitudes--12,500 ft and 15,000 ft--on short-term memory in comparison to 2,000 ft. Seventy-two student pilots and instructors were first administered the Vocabulary, Digit Span, and Digit Symbol subtests from the Wechsler Adult Intelligence Scale-Revised, the Vandenberg Mental Rotation Test, and the near-contrast sensitivity portion of the Vistech VCTS 6000 chart. Participants then spent 1 1/2 hr at their designated altitude for cognitive testing. Participants performed a 30 min vigilance task while listening to an audiotape with instructions to recall radio calls prefaced by their assigned call sign. Half of the radio calls were high memory loads (at least 4 pieces of information), and half were low memory loads (no more than 2 pieces of information). No effects of altitude were found in performance on the Vigilance task. However, for readbacks of high memory load, significant deficits in recall were observed at 12,500 ft and 15,000 ft, whereas no effect of altitude was observed on recall of readbacks with low memory loads. These results indicate that, at altitude, short-term memory was exceeded for the readbacks requiring a larger amount of information to be recalled, and that cognitive deficits are found at lower altitudes than previously observed.

Effect of inhaled 3% CO2 on Cheyne-Stokes respiration in congestive heart failure.

Cheyne-Stokes respiration (CSR) in severe stable congestive heart failure (CHF) may be associated with significant nocturnal arterial oxygen desaturation and sleep disruption. Previous investigations of inhaled CO2 in CSR have been uncontrolled and of short duration, sleep has not been monitored electroencephalographically, and most patients studied have had neurological disease with or without cardiac disease. The purpose of our study was to document the effects of inhaled CO2 on CSR in patients with severe stable CHF (left ventricular ejection fraction < 35% and NYHA class 3 or 4 dyspnea) in controlled all-night polysomnographic studies. Six patients were studied for 3 nights and days: adaptation, control and inhalation of CO2. These patients received a constant F1CO2 = 0.03 in air (with a 4-5 mm Hg increase in PaCO2) on night 3. This caused virtual abolition of CSR as reflected by CSR duration/total sleep time (62-2.2%; p = 0.0012) and CSR duration/nonrapid eye movement (NREM) sleep time (73-2.4%; p = 0.00064), and NREM apnea index was reduced from 33.5 to zero (p = 0.026). The apparatus used to accurately control F1CO2, however, was intrusive and some features of sleep structure such as sleep latency were adversely affected. We conclude that inhalation of CO2 with a constant F1CO2 = 0.03 virtually eradicates CSR in all-night polysomnographically monitored studies in patients with severe stable CHF. The clinical significance of these findings remains to be determined.

Benzodiazepines in congestive heart failure: effects of temazepam on arousability and Cheyne-Stokes respiration.

We studied seven male patients with moderate to severe congestive heart failure (CHF) [left ventricular ejection fraction (LVEF) = 22.4 +/- 6.7; mean +/- SD] in a double-blind crossover trial to determine the effects of temazepam 15 mg on arousability, sleep architecture, Cheyne-Stokes respiration (CSR) and nighttime oxygen saturation. Sleep architecture was not markedly improved with temazepam. There was no significant change in total sleep time (TST) (383.1 +/- 14.1 minutes to 396.6 +/- 15.4 minutes, p = ns) (mean +/- SE, placebo vs. temazepam) or total wake time (TWT) (96.9 +/- 14.0 vs. 81.4 +/- 14.0 minutes, p = ns). Sleep stage proportions did not change appreciably except for a reduction in stage 1 sleep (6.7 +/- 1.2% vs. 4.0 +/- 1.0%, p < 0.05). Microarousals per hour of sleep decreased with temazepam (21.1 +/- 2.7/hour vs. 13.9 +/- 2.1/hour placebo, p < 0.05), with the largest change occurring in stage 2 (24.9 +/- 5.4/hour vs. 15.0 +/- 3.1/hour, p < 0.05). Wake time during sleep (WDS) was reduced from 82.5 +/- 11.7 minutes to 54.5 +/- 9.4 minutes, p < 0.03. Daytime alertness was improved with temazepam as was indicated by an increase in mean latency to sleep [multiple sleep latency test (MSLT) = 7.1 +/- 2.4 vs. 5.7 +/- 2.0 minutes, p < 0.04) on days following treatment with temazepam. There was no significant change in CSR as a percentage of TST (38.7 +/- 13.6% vs. 32.5 +/- 11.8%, p = ns). However, the apnea/hypopnea index (AHI) (10% filter) was decreased in stage 1 (28.1 +/- 9.7/hour vs. 15.6 +/- 8.2/hour). Overnight oxygen saturation did not change with temazepam (95.1 +/- 0.6% both nights) and the percentage of TST spent below 90% oxygen saturation was minimal for both conditions (1.5 +/- 1.1% vs. 2.2 +/- 1.7%, p = ns). We conclude that CHF patients with CSR experience frequent arousals and that these arousals can be reduced with temazepam. There was an improvement in daytime somnolence. There was no worsening of nighttime oxygen saturation.