Stanson, Anthony W.

Management of transplant renal artery stenosis has been a controversial issue. The authors have reviewed their experience with 31 such cases which represent 3.1% of a transplant population of 1015 patients. Evidence of chronic allograft rejection was noted in 14 of these patients. Ten patients were treated medically. The remaining patients were managed by either percutaneous transluminal angioplasty (8 cases) or surgery (13 cases). Three patients initially treated by percutaneous transluminal angioplasty later underwent surgical repair. Operative intervention resulted in a significant decrease in mean arterial pressure and the greatest degree of therapeutic success (defined as normal blood pressure without use of antihypertensive agents). In contrast to other reports, use of percutaneous transluminal angioplasty was not successful in a majority of patients. This divergence may reflect differences in criteria for success which, we believe, should be defined more rigorously. Our data indicate that decisions regarding definitive management strategies should be based on the specific characteristics of the lesion with identification of stenoses that may be amenable to surgical rather than angioplastic treatment.

Renal fusion or ectopia can present formidable challenges during aortic surgery. To evaluate morbidity and define optimal management, the clinical histories of 120 patients with renal fusion or ectopia who underwent 21 aortic procedures at the authors' institution over a 37-year period were reviewed. Indications for surgery included aortic aneurysm in 16 patients (infrarenal in 15 and thoracoabdominal in one) and aortoiliac occlusive disease in five (with renovascular hypertension in two). The abnormal kidney was detected before surgery in 13 patients (65%) by excretory urography, arteriography, computed tomography, or ultrasonography. Arteriography revealed multiple and/or anomalous renal arteries in nine of 12 patients studied. At surgery, 15 patients (75%) were found to have multiple or anomalous renal arteries. Six required renal revascularization (reimplantation four, endarterectomy one, aortorenal bypass one). The renal symphysis was divided in two patients. There were no operative deaths. Six major complications included bleeding requiring reoperation, renal failure requiring short-term dialysis, pancreatitis, gastrointestinal bleeding, pneumonia and thrombophlebitis. Preoperative aortography is recommended in patients with renal fusion or ectopia because of the high incidence of associated renal artery anomalies. The surgeon must be prepared to preserve or revascularize these anomalous renal arteries. Division of the renal symphysis is rarely required. Although perioperative morbidity is raised, aortic reconstruction in patients with renal fusion or ectopia can be safely performed without increased mortality.

Abstract Intraluminal airway pressure and pharyngeal muscle activity are widely recognized as major determinants of the size and collapsibility of the upper airway. In addition, changes in the volume or pressure of tissue surrounding the pharyngeal airway may significantly influence its size. The present study used fast computed tomography (CT) to determine the effects of changes in central venous pressure (CVP) on upper airway size. Ten awake male patients with obstructive sleep apnea (OSA) were studied. Scans were performed at functional residual capacity (FRC) and at the end of a tidal inspiration (VTei) under three conditions of CVP: (1) at baseline (CVP nl) with patients lying supine; (2) at decreased CVP (CVP-) by inflating blood pressure cuffs to 40 mm Hg on both legs; and (3) at increased CVP (CVP+) by elevating both legs to 33 degrees. At FRC, changes in CVP had no significant effect on either mean or minimum cross-sectional area (CSA) of the upper airway. In contrast, an analysis of variance (ANOVA) indicated that alterations in CVP were associated with changes in mean CSA (p = 0.03) and to a lesser extent in minimum CSA (p = 0.07) at VTei. With the legs elevated (CVP+), neither mean nor minimum CSA showed any significant change with tidal breathing. However, after leg-cuff inflation (CVP-), highly significant increases in both mean (163 +/- 22 to 218 +/- 19 mm2, p = 0.001) and minimum (48 +/- 8 to 85 +/- 12 mm2, p = 0.02) CSA were detected. Changes in mean and minimum CSA with tidal breathing at baseline (CVP nl) were intermediate. These results indicate that changes in CVP significantly alter the response of the upper airway to tidal breathing. They further suggest that increases in upper airway size with tidal breathing may be related to reduction in venous blood volume in pharyngeal and neck tissues as the generation of negative intrathoracic pressure during inspiration increases venous return to the chest.

Abstract Fast-CT scanning was used to study the effects of changes in body position on upper airway (UA) size and shape in 11 awake subjects with obstructive sleep apnea (OSA). Six patients with position (P)-dependent OSA were compared with five patients with nonposition (NP)-dependent OSA. Scans were repeated in the prone (PRN), right side (RS), and supine (SUP) body positions at both functional residual capacity and end-inspiratory tidal volume. Significant group, group by position, and borderline group by respiration effects were detected for minimum but not mean UA dimension data. Significant differences between groups were noted in minimum cross-sectional area and minimum lateral distance but not in minimum anteroposterior distance in the RS and SUP positions. Turning from the PRN to the RS or SUP position tended to decrease UA size in the NP group by decreasing the lateral distance, while the opposite effect was found in the P group. The results indicate that changes in body position during wakefulness affect the lateral but not the anteroposterior dimensions of the UA, and the UA behaves differently in patients with NP and P OSA in response to changes in body position.

Abstract Background Management of patients with bilateral adrenal masses and corticotropin (ACTH)‐independent Cushing syndrome (CS) or subclinical CS is problematic. We report our experience with adrenal venous sampling (AVS) in the evaluation of 10 patients with bilateral masses who had ACTH‐independent CS or subclinical CS. Patients and Methods Ten patients (9 women, 1 man, mean age 56.4 years) with bilateral adrenal masses and ACTH‐independent CS ( n = 3) or subclinical CS ( n = 7) underwent AVS. Autonomous cortisol secretion was documented in all cases with suppressed serum ACTH concentrations and lack of cortisol suppression with dexamethasone administration. Adrenal venous sampling was performed on the second day of dexamethasone administration. Cortisol and epinephrine levels were measured from each adrenal vein (AV) and from a peripheral vein (PV). Results Mean (± SD) maximal diameter of the adrenal masses on computed tomography was 3.3 ± 1.3 cm (range: 1.2–6.0 cm). Successful catheterization was confirmed with AV:PV epinephrine gradients. A cortisol AV:PV gradient >6.5 was consistent with a cortisol‐secreting adenoma in 11 adrenal glands; 5 patients had clinically important bilateral autonomous cortisol hypersecretion, 3 had bilateral cortisol‐secreting adenomas, and 2 had ACTH‐independent macronodular adrenal hyperplasia. Adrenal venous sampling‐guided adrenalectomy was completed in all 10 patients—2 patients had total bilateral adrenalectomy and 2 others had subtotal bilateral adrenalectomy. During a mean follow‐up of 36.1 months (range: 0.7–123 months), CS or clinically important cortisol secretory autonomy did not recur. Conclusions Adrenal venous sampling contributed to the localization of autonomous hypercortisolism in the setting of ACTH‐independent CS or subclinical CS in patients with bilateral adrenal masses.

Medical and surgical emergencies occasionally present as ruptured abdominal aortic aneurysms (RAAA). To assess benefits of laparotomies and adverse effects of unnecessary operations, the authors reviewed their experience. Thirteen patients, 9 women, 4 men (mean age: 72 years, range: 41-85) underwent emergency laparotomy between 1988 and 1996 for presumed RAAA and were found to have other surgical or medical emergencies. All the patients presented with hypotension, 12 had abdominal or back pain, four had pulsatile abdominal mass. Rupture was not excluded by computed tomography scan in three or by ultrasonography in two patients. Laparotomy disclosed intact abdominal aorta in all, but seven patients had abdominal aortic aneurysm. Of five surgical emergencies, laparotomy was indicated in four: three for ruptured visceral artery aneurysms, one for perforated duodenal ulcer. The fifth patient required thoracotomy for ruptured thoracic aneurysm. Four of eight medical emergencies were myocardial infarctions. One iatro genic complication required reoperation for bleeding. Mean hospital stay was 18 days; mean hospital charges were $40,771. Seven (54%) early deaths occurred; none were caused directly by the operation. Laparotomy was indicated in one third of deceptive emergencies that present as RAAA. Although mortality, morbidity, and costs were high, iatrogenic surgical complica tions were rare and deaths were not caused by unnecessary operations.