Dynamic CT for parathyroid disease: are multiple phases necessary?

BACKGROUND AND PURPOSE

A 4D CT protocol for detection of parathyroid lesions involves obtaining unenhanced, arterial, early, and delayed venous phase images. The aim of the study was to determine the ideal combination of phases that would minimize radiation dose without sacrificing diagnostic accuracy.

MATERIALS AND METHODS

With institutional review board approval, the records of 29 patients with primary hyperparathyroidism who had undergone surgical exploration were reviewed. Four neuroradiologists who were blinded to the surgical outcome reviewed the imaging studies in 5 combinations (unenhanced and arterial phase; unenhanced, arterial, and early venous; all 4 phases; arterial alone; arterial and early venous phases) with an interval of at least 7 days between each review. The accuracy of interpretation in lateralizing an abnormality to the side of the neck (right, left, ectopic) and localizing it to a quadrant in the neck (right or left upper, right or left lower) was evaluated.

RESULTS

The lateralization and localization accuracy (90.5% and 91.5%, respectively) of the arterial phase alone was comparable with the other combinations of phases. There was no statistically significant difference among the different combinations of phases in their ability to lateralize or localize adenomas to a quadrant (P = .976 and .996, respectively).

CONCLUSIONS

Assessment of a small group of patients shows that adequate diagnostic accuracy for parathyroid adenoma localization may be achievable by obtaining arterial phase images alone. If this outcome can be validated prospectively in a larger group of patients, then the radiation dose can potentially be reduced to one-fourth of what would otherwise be administered.

A comparison of the haemostatic effect of Vivostat patient-derived fibrin sealant with oxidised cellulose (Surgicel) in multiple surgical procedures

AIM

To evaluate the haemostatic properties of Vivostat patient-derived fibrin sealant in a broad range of surgical procedures.

METHOD

In a prospective, randomised, multicentre, clinical study, typical surgical wounds of 69 patients (cardiothoracic, general, obstetric and gynaecologic, and vascular), requiring intervention to control bleeding, were treated with either Vivostat-derived sealant (n = 35) or Surgicel (n = 34) as required and the time taken to arrest bleeding was assessed.

RESULTS

Compared with Surgicel, the mean time to haemostasis of Vivostat-derived sealant was significantly shorter (1.6 vs. 3.3 min, p < 0.0001) and more patients were successfully treated (i.e. no additional haemostatic measures required; 94 vs. 65%, p = 0.003).

CONCLUSION

Vivostat-derived sealant is a more reliable and rapidly effective surgical haemostat than Surgicel.

Outpatient laparoscopic cholecystectomy: patient outcomes after implementation of a clinical pathway

OBJECTIVE

To determine the success of a clinical pathway for outpatient laparoscopic cholecystectomy (LC) in an academic health center, and to assess the impact of pathway implementation on same-day discharge rates, safety, patient satisfaction, and resource utilization.

SUMMARY BACKGROUND DATA

Laparoscopic cholecystectomy is reported to be safe for patients and acceptable as an outpatient procedure. Whether this experience can be translated to an academic health center or larger hospital is uncertain. Clinical pathways guide the care of specific patient populations with the goal of enhancing patient care while optimizing resource utilization. The effectiveness of these pathways in achieving their goals is not well studied.

METHODS

During a 12-month period beginning April 1, 1999, all patients eligible for an elective LC (n = 177) participated in a clinical pathway developed to transition LC to an outpatient procedure. These were compared with all patients undergoing elective LC (n = 208) in the 15 months immediately before pathway implementation. Successful same-day discharges, reasons for postoperative admission, readmission rates, complications, deaths, and patient satisfaction were compared. Average length of stay and total hospital costs were calculated and compared.

RESULTS

After pathway implementation, the proportion of same-day discharges increased significantly, from 21% to 72%. Unplanned postoperative admissions decreased as experience with the pathway increased. Patient characteristics, need for readmission, complications, and deaths were not different between the groups. Patients surveyed were highly satisfied with their care. Resource utilization declined, resulting in more available inpatient beds and substantial cost savings.

CONCLUSIONS

Implementation of a clinical pathway for outpatient LC was successful, safe, and satisfying for patients. Converting LC to an outpatient procedure resulted in a significant reduction in medical resource use, including a decreased length of stay and total cost of care.

Impaired insulin secretion and increased insulin sensitivity in familial maturity-onset diabetes of the young 4 (insulin promoter factor 1 gene)

Diabetes resulting from heterozygosity for an inactivating mutation of the homeodomain transcription factor insulin promoter factor 1 (IPF-1) is due to a genetic defect of beta-cell function referred to as maturity-onset diabetes of the young 4. IPF-1 is required for the development of the pancreas and mediates glucose-responsive stimulation of insulin gene transcription. To quantitate islet cell responses in a family harboring a Pro63fsdelC mutation in IPF-1, we performed a five-step (1-h intervals) hyperglycemic clamp on seven heterozygous members (NM) and eight normal genotype members (NN). During the last 30 min of the fifth glucose step, glucagon-like peptide 1 (GLP-1) was also infused (1.5 pmol x kg(-1) x min(-1)). Fasting plasma glucose levels were greater in the NM group than in the NN group (9.2 vs. 5.9 mmol/l, respectively; P < 0.05). Fasting insulin levels were similar in both groups (72 vs. 105 pmol/l for NN vs. NM, respectively). First-phase insulin and C-peptide responses were absent in individuals in the NM group, who had markedly attenuated insulin responses to glucose alone compared with the NN group. At a glucose level of 16.8 mmol/l above fasting level, GLP-1 augmented insulin secretion equivalently (fold increase) in both groups, but the insulin and C-peptide responses to GLP-1 were sevenfold less in the NM subjects than in the NN subjects. In both groups, glucagon levels fell during each glycemic plateau, and a further reduction occurred during the GLP-1 infusion. Sigmoidal dose-response curves of glucose clearance versus insulin levels during the hyperglycemic clamp in the two small groups showed both a left shift and a lower maximal response in the NM group compared with the NN group, which is consistent with an increased insulin sensitivity in the NM subjects. A sharp decline occurred in the dose-response curve for suppression of nonesterified fatty acids versus insulin levels in the NM group. We conclude that the Pro63fsdelC IPF-1 mutation is associated with a severe impairment of beta-cell sensitivity to glucose and an apparent increase in peripheral tissue sensitivity to insulin and is a genetically determined cause of beta-cell dysfunction.

Association of infiltrating lobular carcinoma with positive surgical margins after breast-conservation therapy

OBJECTIVE

To determine whether infiltrating lobular carcinoma (ILC) is associated with high positive-margin rates for single-stage lumpectomy procedures, and to define clinical, mammographic, or histologic characteristics of ILC that might influence the positive-margin rate, thereby affecting treatment decisions.

SUMMARY BACKGROUND DATA

Infiltrating lobular cancer represents approximately 10% of all invasive breast carcinomas and is often poorly defined on gross examination.

METHODS

A group of 47 patients with biopsy-proven ILC undergoing breast-conservation therapy (BCT) at the University of Virginia Health Sciences Center between 1975 and 1999 was compared with a group of 150 patients with infiltrating ductal cancer undergoing BCT during the same time period. The pathology of the lumpectomy specimen was reviewed for each patient to confirm surgical margin status. Office and surgical notes as well as mammography reports were examined to determine whether the lesions were deemed palpable before and during surgery. Patients were stratified according to age, family history, tumor size, tumor location, and histologic features of the tumor.

RESULTS

The incidence of positive margins was greater in the ILC group compared with the infiltrating ductal cancer group. Patient age, family history, and preoperative palpability of the tumor did not correlate with surgical margin status. Of the mammographic features identified, including spiculated mass, calcifications, architectural distortion, and other densities, only architectural distortion predicted positive surgical margin status. Tumor grade, tumor size, lymph node status, and receptor status were not predictive of surgical margin status.

CONCLUSIONS

For patients with ILC, BCT is feasible, but these patients are at high risk of tumor-positive resection margins (51% incidence) after the initial resection. Only the mammographic finding of architectural distortion was identified as a preoperative marker reliably identifying a subgroup of ILC patients at especially high risk for a positive surgical margin. For all patients with ILC considering BCT, careful counseling about the potential need for a second procedure to treat the positive margin should be included in the treatment discussion.

The effect of clinical pathway implementation on total hospital costs for thyroidectomy and parathyroidectomy patients

Clinical pathways have long been used to guide the delivery of patient care in varied practice settings. There is little information in the literature to document the effectiveness of pathway implementation in general surgical populations. This study reports the effect of clinical pathway implementation in two general surgical patient groups, thyroidectomy and parathyroidectomy. Clinical pathways were implemented to serve patients undergoing thyroidectomy and parathyroidectomy surgery. The effects of both clinical pathways on total hospital costs, length of hospitalization, variances, and outcomes were collected and evaluated from July 1998 through July 1999. These data were compared to data from the previous year. The average length of stay for parathyroidectomy patients decreased from 2.4 to 1.5 days (P = 0.26) for pathway patients as compared to prepathway patients. The average cost per case decreased from $5071 to $4291 (P = 0.50) for parathyroidectomy pathway versus prepathway patients. The average length of stay decrease for thyroidectomy patients was 1.4 to 1.2 (P = 0.16) for the pathway to prepathway comparison. The average cost per case decrease was minor at $4117 to $4111. Pharmacy costs and laboratory utilization were effectively reduced. Perioperative costs rose dramatically during this period, operating room/central sterile supply cost per case rose 12 per cent, anesthesia supply cost per case rose 15 per cent, and surgical pathology costs increased 110 per cent overall for both patient groups. Clinical pathway implementation has allowed us to reduce or maintain total hospital costs in the face of rising perioperative costs. We conclude that implementation of these clinical pathways has allowed us to improve consistency with which we deliver care while maintaining the quality of patient outcomes and reducing the costs of care and length of hospital stay.

Preoperative evaluation and predictive value of fine-needle aspiration and frozen section of thyroid nodules

BACKGROUND

We sought to evaluate the predictive value of preoperative fine-needle aspiration (FNA) on surgical decision making by evaluating the final pathologic diagnosis and comparing it to the preoperative diagnosis. Further, we wished to calculate the predictive accuracy of each of several types of preoperative FNA diagnosis.

STUDY DESIGN

A retrospective chart review of 151 thyroid resections between July 1990 and April 1996 at the University of Virginia was undertaken. The mean age was 45 years (range, 11 to 85 years). Preoperative laboratory values, presenting symptoms, imaging studies, and predictive values of preoperative FNA and intraoperative frozen section were analyzed.

RESULTS

Symptomatology was poorly predictive of a benign versus malignant postoperative final pathologic diagnosis. Sensitivity, specificity, and accuracy of frozen section versus FNA was 86% versus 86%; 99% versus 93%, and 96% versus 92%, respectively, if the reading "cancer" or "suspicious" were predicted as positive for malignancy and "benign" or "follicular" were predicted as negative for malignancy. If only the reading "cancer" was predicted as positive for malignancy and only "benign" was predicted as negative for malignancy, sensitivity and specificity for FNA were 100% and 96%, respectively, and 100% and 99%, respectively, for frozen section. Forty-nine "follicular" lesions obtained by preoperative FNA resulted in 46 benign diagnoses after surgical resection.

CONCLUSIONS

The use of preoperative FNA is a powerful diagnostic tool in the hands of skilled pathologists. There is increasing evidence that intraoperative frozen section adds little to intraoperative decision making in patients diagnosed with thyroid cancer by preoperative FNA. Less definitive interpretations decrease the sensitivity, specificity, and accuracy of the FNA diagnosis.

Association of breast cancer with the finding of atypical ductal hyperplasia at core breast biopsy

OBJECTIVE

The purpose of the study is to evaluate the prevalence of occult breast carcinoma in surgical breast biopsies performed on nonpalpable breast lesions diagnosed initially as atypical ductal hyperplasia (ADH) by core needle biopsy.

BACKGROUND

Atypical ductal hyperplasia is a lesion with significant malignant potential. Some authors note that ADH and ductal carcinoma in situ (DCIS) frequently coexist in the same lesion. The criterion for the diagnosis of DCIS requires involvement of at least two ducts; otherwise, a lesion that is qualitatively consistent with DCIS but quantitatively insufficient is described as atypical ductal hyperplasia. Thus, the finding of ADH in a core needle breast biopsy specimen actually may represent a sample of a true in situ carcinoma.

METHODS

Between May 3, 1994, and June 12, 1996, image-guided core biopsies of 510 mammographically identified lesions were performed using a 14-gauge automated device with an average of 7.5 cores obtained per lesion. Atypical ductal hyperplasia was found in 23 (4.5%) of 510 lesions, and surgical excision subsequently was performed in 21 of these cases. In these 21 cases, histopathologic results from core needle and surgical biopsies were reviewed and correlated.

RESULTS

Histopathologic study of the 21 surgically excised lesions having ADH in their core needle specimens showed seven (33.3%) with DCIS.

CONCLUSIONS

In the authors' patient population, one third of patients with ADH at core biopsy have an occult carcinoma. A core needle breast biopsy finding of ADH for nonpalpable lesions therefore warrants a recommendation for excisional biopsy.

General surgical complications can be predicted after cardiopulmonary bypass

OBJECTIVE

The authors review the general surgical complications of cardiopulmonary bypass, including newer procedures such as heart and lung transplantation, to identify patients at higher risk.

SUMMARY BACKGROUND DATA

Although rare, the general surgical complications of cardiopulmonary bypass are associated with high mortality. The early identification of patients at increased risk for these complications may allow for earlier detection and treatment of these problems to reduce mortality.

METHODS

A retrospective review was performed of 1831 patients undergoing cardiopulmonary bypass from 1991 to 1993. This was done to identify factors that significantly contributed to an increased risk of general surgical complications.

RESULTS

Factors associated with an increased risk of general surgical complications included prolonged cardiopulmonary bypass (p < 0.005) and intensive care unit stay (p < 0.002), occurrence of arrhythmias (p < 0.001), use of inotropic agents (preoperatively or postoperatively p < 0.001), insertion of the intra-aortic balloon pump (preoperatively p < 0.005, postoperatively p < 0.001), use of steroids (p < 0.001), and prolonged ventilator support (p < 0.001). Multivariate analysis identified use of the intra-aortic balloon pump (p < 0.001) as the strongest predictor of the general surgical complications of cardiopulmonary bypass. A variety of factors not contributing significantly to an increased risk also were identified.

CONCLUSIONS

Factors indicative of or contributing to periods of decreased end-organ perfusion appear to be significantly related to general surgical complications after cardiopulmonary bypass.

Circulating dihydroxyphenylglycol and norepinephrine concentrations during sympathetic nervous system activation in patients with pheochromocytoma

Although increased plasma norepinephrine (NE) concentrations mediate vasoconstriction during episodic hypertension and hypertensive crises in patients with pheochromocytoma (Pheo), the precise origin of this circulating NE (tumor or sympathetic nerves) is not known. Dihydroxyphenylglycol (DHPG), a deaminated metabolite of NE, is formed principally in sympathetic nerve endings. Under basal conditions, plasma NE and DHPG concentrations correlate closely, and during sympathetic nervous system activation, both plasma NE and DHPG concentrations increase. This observation suggests that plasma DHPG concentrations may reflect the source of circulating NE (tumor or sympathetic nerves) during hypertensive episodes in patients with Pheo. Plasma NE and DHPG concentrations were measured simultaneously, and the NE/DHPG ratio was calculated in seven patients with Pheo during 20 min of sympathetic nervous system activation (treadmill exercise) before and after surgical resection of the tumor. Age- and sex-matched normal subjects were also studied. Exercise resulted in a significant increase in plasma NE and DHPG concentrations in patients with Pheo and in normal subjects (Pheo: basal NE, 1827 +/- 639; peak NE, 3016 +/- 769 pg/mL (P = 0.02); normal subjects: basal NE, 266 +/- 27; peak NE, 1166 +/- 197 pg/mL (P = 0.01); Pheo: basal DHPG, 1521 +/- 280; peak DHPG, 2313 +/- 252 pg/mL (P = 0.007); normal subjects: basal DHPG, 870 +/- 50; peak DHPG, 1630 +/- 180 pg/mL (P = 0.01)]. The NE/DHPG ratio increased with exercise in normal subjects (basal, 0.30 +/- 0.02; peak, 0.83 +/- 12; P = 0.005), but did not change in patients with Pheo (basal, 1.22 +/- 0.32; peak, 1.54 +/- 0.27). Exercise also increased plasma NE and DHPG concentrations and the NE/DHPG ratio in five patients studied after surgical resection of the tumor. Systolic blood pressure and heart rate increased significantly during exercise in all three study groups. The increase in plasma NE and HDPG concentrations during exercise-induced sympathetic nervous system stimulation in patients with Pheo is similar to that in normal subjects and may indicate that the sympathetic nervous system plays an important role in the pathogenesis of hypertension and hypertensive crises in patients with Pheo.

Hyperinsulinemia after pancreatic transplantation. Prediction by a novel computer model and in vivo verification

OBJECTIVE

The authors evaluated systemic venous insulin release as a cause of the hyperinsulinemia (HNS) associated with pancreatic transplantation (PTX) with respect to the mechanism and metabolic consequences.

SUMMARY BACKGROUND DATA

Many investigators believe the postoperative anatomy associated with common PTX techniques to be the sole cause of the two- to threefold posttransplantation HINS. However, this concept remains to be conclusively proved and characterized quantitatively.

METHODS

The authors used three approaches to achieve their objectives. First, a computer model was generated based on established data concerning blood flow and tissue insulin extraction to determine whether it was mathematically possible for HINS to be caused by systemic insulin release. Second, HINS clamps were applied to normal dogs using the Andres clamp technique to quantify the in vivo differences in peripheral insulin levels and the metabolic consequences of systemic versus portal insulin infusion. Third, prolonged insulin half-life was evaluated as a possible mechanism of HINS from systemic insulin release by determination of biexponential rates of plasma disappearance from an endogenous pulse of insulin in surgically induced dog models of systemic and portal insulin release.

RESULTS

First, the computer model calculated a 1.4- to 2.9-fold increase in peripheral venous insulin levels with systemic versus portal insulin release, verifying mathematically the concept of HINS resulting from systemic insulin release. Second, the actual systemic insulin infusion produced a 1.3- to 1.4-fold increase in peripheral venous insulin levels compared with portal infusion (p < 0.05). No significant differences in hepatic glucose output, total glucose disposal, or glucose infusion requirements were seen. Third, although the basal insulin level was twofold higher in the surgically induced animal models with systemic insulin release (p < 0.003), there were no differences in biexponential insulin clearance parameters.

CONCLUSIONS

The HINS produced by systemic insulin release did not significantly alter glucose metabolism and was not the result of altered peripheral insulin clearance parameters. In vivo systemic venous insulin infusion studies produce HINS, but not to the degree calculated by mathematic modeling or that occurs after clinical PTX, making it likely that other factors also play a role in the HINS after PTX.

Intraoperative fine needle aspiration of pancreatic and extrahepatic biliary masses

Intraoperative fine needle aspiration (IFNA) of masses of the pancreas and extrahepatic biliary system provides a method of rapid tissue diagnosis with a much lower complication rate than either wedge or large bore needle biopsies. Few series include IFNA of extrahepatic biliary system masses in their analyses. We retrospectively evaluated all IFNA of pancreatic, extrahepatic biliary and ampullary masses at the University of Virginia from March 1981 to December 1991 to assess the diagnostic accuracy of this procedure. Ninety-nine IFNA were performed--75 of the pancreas, 17 of the extrahepatic biliary system and seven of the ampulla. All aspirations were performed with direct visualization or palpation of the tumor, or both, using several passes with a 22 gauge needle. A diagnostic "positive" or "negative" reading was rendered in 90 of 99 IFNA. Carcinoma was confirmed by positive tissue diagnosis or clinical course consistent with cancer. Benign disease was confirmed by negative pathologic factors from a resected specimen or confirmatory clinical course of at least 18 months. Diagnosis was confirmed by these criteria in 82 patients. Thirty-four of 43 patients with confirmed carcinoma of the pancreas had positive cytologic factors by IFNA. Three pancreas IFNA were deemed as "suspicious" and six as "unsatisfactory." Two patients with "suspicious" findings had pathologically confirmed well-differentiated carcinoma. Carcinoma of the ampulla and extrahepatic biliary tract was detected by IFNA in 17 of 18 confirmed patients. The overall sensitivity of positive or negative IFNA in this series in 90 percent, with 100 percent specificity and 92 percent accuracy. IFNA has a positive predictive value of 100 percent and negative predictive value of 74 percent. We conclude that IFNA is a highly accurate diagnostic procedure and represents the preferred technique of obtaining an intraoperative tissue diagnosis in masses of the pancreas, extrahepatic biliary tract and ampulla. Positive IFNA may definitively guide surgical decision-making; however, we caution that negative IFNA cannot be relied on definitively to exclude the diagnosis of carcinoma.

Laparoscopic versus traditional appendectomy for suspected appendicitis

We compared the results of concurrently performed laparoscopic versus open appendectomy as treatments for suspected acute appendicitis. The 68 laparoscopic procedures resulted in 62 appendectomies, 47 by the laparoscopic (LA) technique and 15 by the open (LO) technique. Another 54 patients underwent open appendectomy (OA). Significantly more females underwent laparoscopy (LA and LO: 52% versus OA: 33%, p = 0.047). Operative duration was shortest for OA (81 +/- 3 minutes), which was shorter than for LO (108 +/- 7 minutes), but not different than LA (86 +/- 6 minutes). The postoperative length of stay was not different for LA (3.5 +/- 0.5 days) compared with OA (5.9 +/- 1.6 days) or LO (4.8 +/- 1.3 days). One death occurred in the OA group. Wound complication rates were not significantly different for LA (4.3%) compared with OA (9.4%) and LO (13.3%). Overall complication rates were lower for LA (10.6%) and OA (18.9%) compared with LO (46.7%, p < 0.01). Median hospital cost for LO ($10,425) was higher (p < 0.02) than for either LA ($5,899) or OA ($5,220). When appendicitis was not present, definitive confirmation of pathology was achieved in 9 of 18 patients undergoing LA versus 4 of 14 patients having OA (p = not significant). We conclude that when laparoscopy and laparoscopic appendectomy can be performed, the procedure is safe and produces results comparable with those of open appendectomy without significant overall cost differences.

Intraoperative urinary cyclic AMP monitoring in primary hyperparathyroidism

OBJECTIVE

This study examined the utility of intraoperative urinary cyclic 3'5' adenosine monophosphate (UcAMP), an indicator of parathyroid (PTH) hormone end-organ activity, as a "biochemical frozen section," signaling the real-time resolution of PTH hyperactivity during surgery for primary hyperparathyroidism.

SUMMARY BACKGROUND DATA

The unsuccessful initial neck exploration for primary hyperparathyroidism, leaving the patient with persistent hyperfunctioning parathyroid tissue, results in part from the surgeon's inability intraoperatively to correlate a gland's gross appearance and size estimation with physiologic function. Preoperative imaging, intraoperative imaging, and intraoperative histologic/cytologic surveillance have not resolved this dilemma.

METHODS

Twenty-seven patients underwent a prospective intraoperative UcAMP monitoring protocol. The patients all had a clinical diagnosis of primary hyperparathyroidism and an average preoperative serum calcium of 12.0 +/- 0.3 mg/dl. UcAMP was assayed intraoperatively using 20-minute nonequilibrium radioimmunoassay providing real-time feedback to the operating team.

RESULTS

All patients had an elevated UcAMP confirming PTh hyperactivity at the beginning of the procedure. One patient, subsequently found to have an supernumerary ectopic adenoma, had four normal glands identified intraoperatively, and his intraoperative UcAMP values corroborated persistent hyperparathyroidism, the UcAMP of the remaining 26 patients decreased from 7.0 +/- 1.1 to 2.7 +/- 0.7 nm.dl GF (p < .00005) after complete adenoma excision, and they remain normocalcemic. The protocol provided useful and relevant information to the operating team, and aided in surgical decision-making, in 10 of the 27 cases (37%).

CONCLUSION

Intraoperative biochemical surveillance with ucAMP monitoring reliably signals resolution of PTH hyperfunction. It is a useful adjunct to the surgeon's skill, judgment, and experience in parathyroid surgery.

Successful paratopic pancreas transplantation: a report of three cases with venous portal drainage and enteric exocrine drainage

Pancreatic transplantation is able to produce euglycemia in patients with Type I diabetes mellitus. Current surgical techniques utilize revascularization of the graft through the recipient iliac vessels and drainage of the exocrine pancreatic secretions through a duodenal conduit into the bladder. We describe a technique utilized in 3 patients whereby venous pancreatic drainage is into the portal venous circulation via the proximal splenic vein. The exocrine pancreatic secretions are drained into the proximal jejunum via a side-to-side donor duodenum to proximal small bowel anastomosis. Results and complications of this technique are presented. Potential short-term and long-term advantages and disadvantages of this technique are discussed. Our early experience suggests that paratopic pancreatic transplantation with venous drainage into the portal vein and exocrine drainage into the proximal jejunum is both feasible and desirable.

Laparoscopic cholecystectomy in the obese patient

The authors' experience with laparoscopic cholecystectomy (LC) in obese (O, n = 96) and morbidly obese (MO, n = 27) patient groups was compared with that in the normal weight (NW, n = 174) group of patients as well as the whole group (WG). There were no operative deaths. There were no significant differences between groups for any of the following: successful intraoperative cholangiography (WG, 52.2%; NW, 52.9%; O, 51.1%; MO, 55.6%), conversion to open cholecystectomy (WG, 9.6%; NW, 9.2%; O, 10.4%; MO, 11.1%), incidence of major complications (WG, 4.1%; NW, 3.4%, O, 5.2%; MO, 0%), incidence of minor complications (WG, 7.4%, NW, 7.5%; O, 6.3%; MO, 3.7%), and length of hospitalization after successful LC (WG, 1.25 days; NW, 1.31 days; O, 1.16 days; MO, 1.13 days). Duration of operation did not differ except LC in the MO group (136.4 +/- 6.9 minutes) was longer when compared with NW patients (123.0 +/- 2.9 minutes, p less than 0.05). The authors conclude LC is a safe and effective treatment for obese patients with symptomatic cholelithiasis.

Pancreas transplantation. An initial experience with systemic and portal drainage of pancreatic allografts

Pancreas transplantation has evolved dramatically since its introduction in 1966. As new centers for transplantation have developed, the evaluation of complications associated with pancreas transplantation has led to advances in surgical technique. Furthermore, surgical alterations of the pancreas resulting from transplantation (systemic release of insulin and denervation) are of unproven consequence on glucose metabolism. Since 1988, the authors have performed 21 transplants (16 combined pancreas/kidney, 3 pancreas alone, which includes 1 retransplantation, 1 pancreas after previous kidney transplant, and 1 "cluster") in 20 patients aged 18 to 49 years; mean, 35 +/- 1 years. Overall patient survival is 95%. Three pancreatic grafts failed within the first year because of technical failure; one additional pancreas was lost to an immunologic event on postoperative day 449, for an overall pancreatic graft survival of 81%. No renal grafts were lost. To evaluate causes of graft failure, demographic data were compared, which included age and sex of the donor and the recipient, operative time, intraoperative blood transfusion, and ischemic time of the graft. No statistically significant differences were found between groups except for ischemic time (11.7 +/- 6.4 hours for the technical success group versus 19.8 +/- 3.7 hours for the technical failure group; p less than 0.05 by unpaired Student's t test). Quadruple immunosuppression was used, which included prednisone, cyclosporine, azathioprine, and antilymphoblast globulin. A mean of 1.2 (range, 0 to 3) rejection episodes per patient occurred. Mean hospital stay was 24 +/- 11 days. Surgical and infectious complications were evaluated by comparing the technical success (TS) group (n = 17) with the technical failure (TF) group. Surgical complications in the TS group revealed a mean of 1.3 episodes per patient, whereas the TF group had 3.7 episodes per patient. The TS also had a reduced incidence of infectious complications compared with the TF (1.7 versus 4.3 episodes per patient). Cytomegalovirus was common in both groups, accounting for 11 infectious episodes, and occurred on a mean postoperative day of 38. Mean postoperative HbA1C levels dropped to 5 +/- 1% from 11 +/- 3%. The authors developed a new technique that incorporates portal drainage of the pancreatic venous effluent in three recipients. Preoperative metabolic studies disclosed a mean fasting glucose of 211 +/- 27 mg/dL and a mean stimulated glucose value of 434 +/- 41 mg/dL for all patients; the mean fasting insulin was 23 +/- 4 microU/mL.(ABSTRACT TRUNCATED AT 400 WORDS)

Surgical alterations of the pancreas and insulin-independent glucose disposal

Systemic drainage of pancreatic venous effluent and denervation of the pancreas that follows pancreatic transplantation has been shown to alter postoperative glucose disposal despite elevated levels of peripheral insulin in response to a glucose challenge. Since an appreciable fraction of postprandial glucose disposal takes place in the absence of insulin (insulin-independent glucose disposal--IIGD), we have investigated potential changes in this aspect of carbohydrate metabolism before and after bladder-drained pancreatic auto-transplantation (PAT/B) as well as partial pancreatectomy (PPx). The hyperglycemic clamp protocol with a background infusion of somatostatin was performed on control (PREOP) dogs as well as PAT/B and PPx animals. The rate of glucose disposal (M Value) during the period of hypoinsulinemia induced by Somatostatin (SST) was measured and reported. Whereas glucose disposal during steady state hyperglycemia was significantly diminished for both PPx and PAT/B in the absence of SST, IIGD was unaltered across all three groups studied. We therefore conclude that surgical alteration of the pancreas results in abnormal glucose disposal during steady state hyperglycemia despite apparently normal to supranormal levels of peripheral insulin, and that alterations in IIGD are not responsible for these differences.

Laparoscopic cholecystectomy. Treatment of choice for symptomatic cholelithiasis

Our initial experience with laparoscopic cholecystectomy (LC) for symptomatic cholelithiasis has involved 152 patients. Patient age ranged from 17 to 83 years; most were female (78%). Their average weight was 170 pounds (range, 75 to 365 lbs.). Twenty-two per cent had a single gallstone, while 9% had two to three stones and 64% had more than three stones. Exclusion criteria initially included upper abdominal scarring, severe acute cholecystitis, choledocholithiasis, and inability to tolerate general anesthesia. The first two of these are now only relative contraindications with increased experience. Thirteen of the one hundred fifty-two procedures (8.5%) required conversion to an open operation. Average time of operation was 138 minutes. Intraoperative cholangiography was attempted in 78% of cases and was completed successfully in 66% of those attempted. There have been no deaths. The complication rate has been low: 4% major, 0% life-threatening, and 7.2% minor complications. Postoperative analgesic requirements are remarkably low: 36% of patients required no narcotics after leaving the recovery room. Eighty-seven per cent of patients successfully undergoing LC were discharged by the first postoperative day. Most patients resumed normal activities within 1 week after discharge. Laparoscopic cholecystectomy offers the majority of patients with symptomatic cholelithiasis an improved treatment option, resulting in significantly less postoperative pain, hospitalization, and recuperation time.

Glipizide treatment of pancreas autotransplantation: effects on alterations in glucose-insulin relationships

Pancreas transplantation has been proven effective in supplying an endogenous insulin supply in diabetics. However, alterations in glucose metabolism after transplantation suggest a possible "insensitivity" to its action in the periphery. We hypothesized that sulfonylurea treatment of canines who had received segmental pancreas autotransplants would correct these alterations by altering peripheral insulin sensitivity. Glipizide therapy (5 mg p.o. b.i.d.) did appear, in fact, to enhance basal insulin sensitivity by lowering fasting glucose (100 +/- 3 to 81 +/- 11 mg/dl pre-treatment to post-treatment) while not affecting basal insulin levels. However, glipizide therapy was associated with decreased insulin response to challenge by either oral glucose (2 gm/kg) or sustained intravenous hyperglycemia (150 mg/dl above basal). We conclude that our model of pancreas autotransplantation documents alterations in glucose metabolism which are devoid of the effect of immunosuppression. Glipizide treatment appears to affect fasting sensitivity to insulin, but results in a decrement of insulin response to oral or intravenous glucose challenge.

Effect of verapamil on insulin-stimulated choleresis

Insulin is one of several neurohumoral substances known to have a choleretic effect in vivo and in the isolated perfused rat liver. Infusion of insulin in the perfused rat liver preparation results in stimulation of bile acid-independent bile flow evidenced by increased bile flow, decreased bile acid concentration, and stable bile acid output. The mechanism of insulin-stimulated choleresis is unknown but may involve calcium as an intracellular second messenger. The present studies were performed to assess the role of membrane calcium channels in mediating choleresis and insulin-stimulated bile acid-independent bile flow in the in situ perfused rat liver. We have shown that verapamil, a specific calcium channel blocker, has no effect on bile flow, bile acid concentration, or bile acid output during bile acid-stimulated choleresis at a taurocholate infusion rate of 40 or 80 nmole/g liver/min. Insulin caused a significant increase in bile flow (18-30%) and a decrease in bile acid concentration (13-21%) without affecting bile acid output at a taurocholate infusion rate of 40 or 80 nmole/g liver/min. Verapamil failed to inhibit insulin-stimulated choleresis at a taurocholate infusion rate of 80 nmole/g liver/min. Although we observed an insulin-stimulated increase in bile flow and a decrease in bile acid concentration in the presence of verapamil at a taurocholate infusion rate of 40 nmole/g liver/min, these changes failed to reach statistical significance. We conclude that verapamil has no effect on choleresis or insulin-stimulated bile flow in the perfused rat liver and that the mechanism by which insulin promotes bile acid-independent bile flow is not mediated by verapamil-sensitive calcium channels.

Great expectations: stress and the medical family. 1987 Committee on Issues, Association for Academic Surgery

The high divorce rate and significant stress experienced by families of academic surgeons stimulated the Committee on Issues of the Association of Academic Surgery to choose medical family stress as the topic for the 1987 Committee presentation at the annual meeting. The Committee hoped to provide insight into the cause of this stress and new strategies for coping with this pervasive problem. Forty-three percent of the 505 surgeons who entered the Association from 1981 through 1984 and 38% of their spouses responded to a questionnaire covering issues of time management, response to stress, child rearing, financial security, and spouse career. A panel consisting of Shirley P. Levine, M.D., Hiram C. Polk, Jr., M.D., and Lane A. Gerber, Ph.D., after discussing the questionnaire results, recommended realistic goal setting, specific prioritization of activities, recognition of the considerable contributions of the spouse, and insight into personal limitations as mechanisms for improving family function.

Insulin-dependent and insulin-independent effects after surgical alterations of the pancreas

Anatomic alterations of the pancreas result in physiologic alterations that have not been completely analyzed. Insulin plays a major role in carbohydrate metabolism; nevertheless, as much as 50% of a hyperglycemic load may be metabolized independent of insulin. We analyzed the effects of surgical alterations of the pancreas on postoperative glucose metabolism, including insulin-independent effects. Mongrel female dogs underwent one of three procedures: proximal partial pancreatectomy (PPx), PPx plus diversion of pancreatic venous effluent to the systemic circulation (SC), or PPx plus segmental pancreatic autotransplantation (PAT). Intravenous glucose tolerance tests, with or without a background infusion of somatostatin (SST; 400 ng/kg/min) were performed on all animals preoperatively and postoperatively. SST completely suppressed secretion of assayable peripheral insulin. The rate of glucose disposal during SST suppression approximates the rate of insulin-independent glucose disposal (IIGD). Although there was a significant decrease in the rate of glucose disposal during SST infusion when compared with the rate without SST, no differences in IIGD were found between postoperative groups. IIGD was calculated at 50% to 55% for control, PPx, and SC groups and at 67% for PAT. Peripheral sensitivity to an exogenous insulin infusion (euglycemic clamp) was unchanged by any of the procedures. We conclude that surgical alteration of the pancreas, including pancreas transplantation, results in altered glucose handling in the face of "normal" peripheral levels of insulin. Changes in IIGD and analysis of peripheral sensitivity to insulin do not explain these alterations completely.

Effect of glipizide on the surgically altered pancreas

Surgical alterations of the pancreas affect peripheral glucose, insulin, and glucagon levels with accompanying changes in carbohydrate metabolism. The sulfonylurea glipizide has been used to treat insulin-deficient states; however, its mechanism is not completely known. We hypothesized that glipizide would correct postoperative changes in glucose handling in a way that would allow more complete understanding of the drug's action. Two surgical groups (Group 1:80 percent proximal pancreatectomy; Group 2: proximal pancreatectomy plus splenocaval diversion) were compared with a healthy control group (Group 3). We have concluded that glipizide may have affected basal insulin sensitivity in the control group and Group 2 animals without affecting insulin secretion in response to oral or intravenous glucose stimulation. Glipizide does not correct the alterations in glucose handling or insulin secretion after reduction in beta-cell mass.

Peripheral insulin release after pancreatic resection: the effect of decreased beta-cell mass with systemic or portal drainage

Surgical alteration of the pancreas can result in several anatomic alterations which may affect insulin release. We evaluated the effects of resection, systemic drainage, and autotransplantation of the canine pancreas on peripheral insulin levels and glucose disposal as measured by iv glucose tolerance tests (IVGTT) and a steady state hyperglycemic challenge (clamp). Proximal pancreatectomy (PPx) with reduced beta-cell mass and intact portal drainage resulted in a modestly elevated fasting glucose level and increased integrated glucose response to IVGTT. Compared to preoperative normals, basal insulin was unchanged from preoperative controls; however, peak insulin and integrated insulin response to IVGTT were decreased in PPx animals. Splenocaval drainage or autotransplantation of the distal pancreas resulted in normalization of the severely altered insulin response and fasting glucose levels. K values were significantly reduced after all three procedures. Clamp studies confirmed the basal glucose and insulin findings of the IVGTT. During the clamp, PPx animals had peripheral insulin values approximately 50% of normal controls, while autotransplantation and splenocaval drainage animals had insulin values that approximate normal controls. All three postsurgical groups had blunted insulin levels during stable hyperglycemia. Glucose utilization rates were severely decreased in all three groups. Reduction of beta-cell mass with intact portal drainage resulted in reduced insulin response to glucose challenge by either IVGTT or clamp. Systemic drainage of this same reduced beta-cell mass resulted in peripheral insulin levels comparable to normal controls. Denervation (autotransplantation) had little additive effect. All three groups demonstrated severely decreased rates of glucose disappearance as measured by both IVGTT and clamp studies. Therefore, reduction in beta-cell mass, drained systemically or portally, results in altered glucose disposal regardless of the peripheral insulin levels.

Choledochocele: a rare form of choledochal cyst

Choledochocele is the least common form of cystic dilatation of the biliary tree. Whether this condition is a congenital abnormality or the result of inflammation at the papilla of Vater is not clear. In most cases, the clinical presentation is that of intermittent abdominal pain, nausea, and vomiting, with biliary colic and/or jaundice. As described in our case, choledochocele has characteristic radiologic features, but the lesion can be easily overlooked if one is not aware of its distinctive appearance.

Experimental studies of biliary excretion of piperacillin

The nonrecirculating isolated perfused rat liver was used to study biliary antibiotic excretion by the liver in a steady-state, controlled environment in which bile flow, bile salt output, and antibiotic delivery were maintained under constant conditions. The effects of piperacillin, ampicillin, and gentamicin on bile flow and bile salt output were analyzed; none altered bile salt output, and only high concentrations of piperacillin (100 micrograms/mL) increased bile flow. The ratio of antibiotic concentration in bile and perfusate depended on the type of antibiotic and perfusate concentration. Piperacillin infusions at perfusate concentrations of 50 or 100 micrograms/mL (in the presence of 60 microM taurocholate) yielded bile to perfusate ratios of 112 +/- 10 versus 49 +/- 3, respectively. Using similar perfusate, the concentration ratios for ampicillin (20 micrograms/mL) and gentamicin (10 micrograms/mL) were only 3.4 +/- 0.5 and 0.5 +/- 0.1, respectively. By altering the perfusate to contain either 60 microM or 240 microM taurocholate, we found variance in bile salt output from 27 +/- 1 to 115 +/- 2 mumol/h, yet this alteration had little effect on the output of ampicillin (perfusate concentration of 20 micrograms/mL), 73 +/- 7 versus 74 +/- 12 micrograms/h, or piperacillin (perfusate concentration 100 micrograms/mL), 10 +/- 1 versus 11 +/- 2 mg/h. Thus, it appears ampicillin and piperacillin are excreted into bile at high concentrations by bile salt-independent pathways. Partial biliary obstruction (6 cm H2O) results in significant decreases in bile volume. Infusion of 50 micrograms/mL of piperacillin resulted in increased biliary flow that approached nonobstructed values. Obstruction resulted in significant decreases in bile piperacillin concentration. Whether the choleretic effect of high concentrations of piperacillin has any clinical significance in nonobstructed or obstructed conditions remains to be established.

Evaluation of insulin secretion after pancreas autotransplantation by oral or intravenous glucose challenge

Segmental pancreatic autotransplantation is accompanied by surgical alterations to the pancreas that may have consequences for carbohydrate metabolism. Four mongrel dogs were evaluated before operation and sequentially until 40 weeks after total pancreatectomy and autotransplantation of the splenic lobe of the pancreas with bolus intravenous and oral administration. Intravenous glucose tolerance test (IVGTT) (0.5 g/kg) revealed maintenance of fasting euglycemia for as long as 40 weeks after operation. Peak glucose and integrated glucose values did not show significant changes as a result of autotransplantation. Following transplantation, a delayed peak insulin response was seen; however, basal, peak, and integrated insulin values were largely unaltered. Only K values, a measure of glucose disposal, showed severe alterations (2.44 +/- 0.21 before operation to 1.24 +/- 0.30 at 40 weeks after operation). Oral glucose tolerance tests (OGTT) (2.0 g/kg) demonstrated an increased peak hyperglycemic response after autotransplantation with increased integrated glucose responses. Insulin levels remained at those levels seen before operation, and glucose-dependent insulinotropic polypeptide (GIP) responses were unchanged during the OGTT as late as 20 weeks after operation. In conclusion, pancreas autotransplantation after total pancreatectomy results in significant metabolic alterations that the IVGTT fails to detect with absolute glucose or insulin levels. However, K values are significantly lowered, which indicates alterations in cellular glucose transport. The OGTT demonstrates hyperglycemia without increased insulin or GIP levels, which suggests an altered beta cell response to the enteric stimulus of insulin release. These changes are nonetheless well tolerated by animals that have remained clinically healthy and euglycemic in the basal state.

Solitary hamartomatous polyp of the duodenum in the absence of familial polyposis

A large hamartomatous polyp of the Peutz-Jegher type was discovered in the distal duodenum by endoscopy in a patient with occult gastrointestinal bleeding. There were no other polyps in the gastrointestinal tract and the patient lacked any stigmata associated with the familial polyposis syndromes. This is the second well-documented case of an isolated hamartomatous polyp of the Peutz-Jegher type in the small intestine occurring in the absence of familial polyposis.

Primary small bowel malignancies

Fifty-five patients with primary small bowel malignancies were evaluated from 1955 to 1983. Twenty-seven patients (49%) had carcinoid tumors, 16 (29%) had adenocarcinomas, and 12 (22%) had leiomyosarcomas. The average age at presentation was 68 years (range: carcinoids, 27-82; leiomyosarcomas, 36-75; adenocarcinomas, 40-83). Carcinoids and leiomyosarcomas were 1.7 and 2.0 times, respectively, more common in men; adenocarcinomas showed no sex predominance. Eighty-nine per cent of all patients had symptoms: abdominal pain in 65 per cent, obstruction in 23 per cent, bleeding in 8 per cent, and palpable mass in 5 per cent. Although 27 per cent of carcinoid patients were asymptomatic, 40 per cent exhibited the carcinoid syndrome. Symptoms were longstanding in the majority of cases, and, at the time of diagnosis, 49 per cent of the carcinomas were metastatic. Fifty-five per cent of the tumors were in the ileum, 24 per cent in the jejunum, and 21 per cent in the duodenum. Fifty-five patients (89%) underwent resection for palliation or cure. Five adenocarcinoma patients (32%) survived 1 year, and one (6%) lived 10 years. Twenty-five per cent of leiomyosarcoma patients survived for 10 years. Eighty-seven per cent of patients with carcinoids survived for 1 year, 39 per cent for 5 years, and 22 per cent for 10 years. Previous reports have documented the difficulty of diagnosing these lesions, as does the present study. A higher degree of physician awareness and a more aggressive investigation of referable symptoms should lead to earlier treatment and better long-term results.

The hepatic extraction of gastric inhibitory polypeptide and insulin

The hepatic extractions of gastric inhibitory polypeptide (GIP) and insulin were determined using in vitro and in vivo methods to assess the role of the liver in GIP metabolism and the possible effect of GIP on the hepatic extraction of insulin. During in vitro studies using the isolated perfused rat liver, infusion of GIP (2000 pg/ml) alone and in combination with porcine insulin (200 microU/ml) resulted in negligible hepatic extraction of immunoreactive GIP (IR-GIP) in both fed and fasted animals during either physiologically euglycemic or hyperglycemic perfusions. Hepatic extraction of insulin, however, ranged from 26-36% in fasted animals and from 7-25% in fed animals. Hepatic extraction of insulin and net hepatic glucose appearance were minimally affected by GIP. In vivo studies in awake dogs were then performed, in which simultaneous portal and peripheral venous levels of IR-GIP, immunoreactive insulin (IRI), and glucose were assessed after intraduodenal glucose administration. The portal to peripheral (PORT/PERI) venous ratio of endogenous IRI and IR-GIP reflected the findings of the in vitro studies; the PORT/PERI ratio of IRI levels rose from a basal value of 1.9 +/- 0.3 to a peak of 3.7 +/- 0.9, while the PORT/PERI ratio of IR-GIP levels rose from a basal value of 1.0 +/- 0.1 to a peak of 1.4 +/- 0.2, then rapidly returned to 1.0. The in vivo data are consistent with a continuous hepatic extraction of 40-50% of the insulin entering the liver and a negligible hepatic extraction of IR-GIP. We conclude that hepatic extraction of GIP in vitro or in vivo is minimal. In addition, while the fed state of the animal before infusion can result in changes in the in vitro hepatic extraction of insulin, GIP does not mediate these changes.

Postoperative recurrence in Crohn's disease. The effect of the initial length of bowel resection and operative procedure

We reviewed the surgical experience of 61 patients with Crohn's disease who have received surgical treatment over a 32-year period. Sex, age at onset of symptoms, associated systemic abnormalities, presenting symptoms, indication for previous surgery, and site of disease were not significant predictors of postoperative recurrence. Certain extensive resections of the small bowel are associated with a decreased probability of rehospitalization and reoperation. Resection of more than 25 cm of the small bowel and more than 50 cm of the "total" (small plus large) bowel was associated with a decreased likelihood of recurrence. Interestingly, analysis of larger resections (50, 75, 100 cm) failed to document a decreased likelihood of recurrence. The amount of large bowel resected did not predict postoperative recurrence. Bypass and diversion procedures offer a significantly enhanced risk for recurrent disease, whereas procedures employing resection are associated with lower probabilities of recurrent disease. We conclude that technically adequate resections of 25 to 50 cm of the small bowel or the combined small and large bowel are associated with a decreased probability of reoperation or rehospitalization after the initial surgery for Crohn's disease.

Hepatic resection for metastatic cancer

One-year survival is infrequent in patients with metastatic cancer to the liver. This report includes 21 patients who underwent hepatic resection between 1974 and 1981. Operative procedures included one trisegmentectomy, 12 right hepatic lobectomies, two left hepatic lobectomies, two left lateral segmentectomies, and four wedge resections. Operative morbidity and mortality rates were 43% and 5%, respectively. Life-table analysis revealed an overall 7-year survival rate of 34%. The subset of patients (16) with colorectal adenocarcinoma had a 7-year survival rate of 29% after hepatic resection. In three patients with colorectal adenocarcinoma, frequent CEA determinations were made after surgery in order to calculate the serum half-life of CEA. The data fitted a biexponential function yielding two half-lives for CEA disappearance, 0.8 +/- 0.5 days and 25.9 +/- 10.3 days. We conclude that hepatic resection for isolated hepatic metastases can be performed with acceptable morbidity, low mortality, and prolongation of patient survival.

Insulin's effect on bile flow and lipid excretion during euglycemia and hypoglycemia

Mongrel dogs were prepared by cholecystectomy, ligation of the lesser pancreatic duct, and insertion of modified Thomas cannulas into the stomach and duodenum. When the dogs had recovered from surgery, studies were performed on them, conscious and unanesthetized after an overnight fast. The common bile duct was catheterized through the opened duodenal cannula for collection of hepatic bile. Bile flow was stabilized by the intravenous infusion of sodium taurocholate. After 2 hr of taurocholate infusion, insulin was added to the infusion and continued for the duration of the experiment. Glucose was administered intravenously during the first 120 min of insulin administration to maintain euglycemia; then the glucose was discontinued. The intravenous infusion of insulin during euglycemia maintained by glucose infusion caused a significant increase in bile flow and a decrease in bile salt concentration, but no change in bile salt output. There was a decrease in cholesterol concentration and output and in phospholipid concentration, but no significant change in phospholipid output. When glucose infusion was discontinued and hypoglycemia occurred, there was a further significant increase in bile flow, but no other change. These studies demonstrate that the choleretic action of insulin is not dependent upon hypoglycemia and that intravenously administered insulin may cause increased bile secretion without increase in serum glucagon concentration. These experiments also confirm that insulin choleresis may be associated with a decline in cholesterol output.

Somatostatin suppression of canine fasting bile secretion

Somatostatin, a peptide present in hypothalamus, gastric mucosa, and pancreas, suppresses several gastrointestinal functions. We evaluated the effect of graded doses of intravenous somatostatin on taurocholate-stimulated bile flow awake fasting dogs. Somatostatin doses of 1.5-200 ng . kg-1 . min-1 significantly suppressed fasting biliary flow. Biliary lipid concentration showed progressive elevations approaching 200% with 200 ng . kg-1 . min-1 somatostatin, while lipid outputs were not altered. The data suggest that somatostatin inhibited bile salt-independent canalicular or ductular secretion, because bile flow, chloride, and bicarbonate output, and the biliary clearance of erythritol were significantly reduced, while bile salt output remained unchanged. In addition, suppression of basal insulin concentration occurred at somatostatin infusion of 200 ng . kg-1 . min-1. Additional studies in anesthetized dogs demonstrated that somatostatin could suppress bile secretion without altering hepatic blood flow.

Gastrointestinal complications after cardiopulmonary bypass

Gastrointestinal (GI) complications after surgery requiring cardiopulmonary bypass (CPB) can be serious, often lethal events. In our study, from 1970 through 1981 there were 43 such complications after 5080 CPB cases (0.85%). We noted on annual persistent occurrence of approximately 1%. The overall mortality rate was 63%. The most frequent complication was hemorrhage (usually gastroduodenal). Other complications encountered were pancreatitis, cholecystitis, hyperbilirubinemia, bowel perforations or infarcts, and gastroduodenal alterations. We concluded that GI complications after CPB are associated with a high mortality rate and often occur with other complications. Careful judgment is needed for appropriate diagnosis and therapy.

Marginal ulcer. A difficult surgical problem

One hundred sixty-six patients with documented recurrent or marginal ulcers following previous ulcer operations were seen at Duke Medical Center and the Durham VA Hospital from 1950 through 1980. Patients with the diagnosis of gastrinoma were excluded from the series. Evaluation of initial operation for recurrent ulcer showed that the highest recurrence rate occurred following non-acid-reducing operations. Analysis of the symptom-free interval following initial ulcer operation showed a significantly longer interval prior to recurrent ulcer development following gastroenterostomy than other procedures, while resection and Billroth I reanastomosis showed a significantly shorter symptom-free interval than did other procedures. Endoscopy proved 85% sensitive in making the diagnosis of marginal ulcer, while upper GI series was 71% sensitive. Surgical treatment of 132 patients resulted in a 20.4% recurrence rate of second marginal ulcer, with a 2.3% mortality rate and a 10.6% morbidity rate. Second operation for recurrent ulcer in 24 patients yielded no deaths, a 12.5% morbidity rate, and a 29.2% recurrence rate. Average follow-up for the series was 12.3 years, and ultimate outcome of treatment showed, of patients not lost to follow-up, a 58.2% satisfactory to excellent rating, while 42.8% of patients had an unsatisfactory result of treatment.

Effect of total laryngectomy on esophageal motility

Total laryngectomy for cancer can result in dysphagia and altered esophageal motility. Manometric changes in the upper esophageal sphincter (UES), and in proximal and distal esophageal function have been reported. However, most studies have failed to take into account radiation therapy and appropriate controls. We selected ten male patients (54.3 +/- 1.9 yr) for longitudinal manometric evaluation prior to laryngectomy then at two weeks and again six months later. No patient received preoperative radiation therapy, had a previous history of esophageal surgery, or developed a postoperative wound infection or fistula. Seven of ten patients had positive nodes and received 6,000-6,600 rads postoperative radiation therapy. Preoperatively 4 of 10 patients complained of dysphagia which did not significantly change following surgery and radiation. Two of three patients who did not complain of dysphagia preoperatively and received radiation postoperatively developed dysphagia. No patient without dysphagia preoperatively who received no radiation therapy developed symptoms. Our studies show that laryngectomy causes alterations in the UES resting and peak pressures but not in the proximal or distal esophagus, or the lower esophageal sphincter. These data also imply radiation therapy may be associated with progressive alterations in motility and symptomatology. Further study regarding the effects of radiation on esophageal motility and function are urged.

Chronic primary intestinal pseudo-obstruction

Chronic primary intestinal pseudo-obstruction (CPIP) has received attention despite of its unclear etiology and infrequent occurrence. Recently a patient with this disorder had evidence of a primary visceral neuropathy. Reviewing the literature, we found 30 case reports of CPIP and evaluated their clinicopathologic findings. Presenting symptoms and radiologic findings were nonspecific. Esophageal motility was abnormal in 12 of 14 reports. Intestinal histopathology revealed normal muscle wall, mucosa, and ganglion cells in over 50% of reports. Only 48% of cases demonstrated clinical improvement. Thirty percent (8 of 30) ultimately died. We conclude that CPIP is a perplexing, often fatal entity that can mimic mechanical obstruction in the absence of definite etiology. Primary neurologic or muscular disease may be a possible explanation, but, as yet, definite documentation does not exist.

Postoperative function of "free" jejunal transplants for replacement of the cervical esophagus

The postoperative function of "free" jejunal autotransplants for replacement of the pharyngoesophagus after palliative resection was evaluated in nine patients using clinical assessment, cinefluoroscopy, manometry, and electrical studies. After an initial period of adjustment, all patients swallowed solids and liquids with minimal difficulty, gained weight appropriately and were satisfied with their operations. Cinefluoroscopy and esophageal manometry demonstrated normal function of the intact distal esophagus, which correlated with the absence of reflux symptoms. The grafts were capable of contraction in response to local distension and maintained an intrinsic myoelectrical activity. These results indicate that jejunal autotransplantation may provide excellent palliation with restoration of a near normal swallowing mechanism for patients with large resectable lesions of the pharyngoesophagus. An additional observation was that the instillation of food directly into the gastric antrum caused a change in the motor activity in the transplantd jejunum, indicating physiological hormonal control of intestinal motility.

Selective biliary secretion of basal and glucagon-inhibited neutral sterol after triparanol administration

Biliary cholesterol secretion was studied in dogs with chronic bile fistulas, using glucagon, an inhibitor of biliary cholesterol secretion, and triparanol, an inhibitor of cholesterol synthesis. Glucagon inhibited neutral sterol secretion before and after triparanol administration. Triparanol caused a significant accumulation in bile of the cholesterol precursor desmosterol which comprised a significant portion of the neutral sterol in bile but not in blood. Glucagon inhibited both biliary desmosterol and cholesterol secretions to a similar degree. These findings suggest that biliary cholesterol is derived from newly synthesized hepatic sterol as well as from equilibrated sources. Furthermore, glucagon suppressed biliary secretion of both equilibrated as well as newly synthesized neutral sterol, suggesting that glucagon inhibits the movement of neutral sterol to or through the canalicular membrane.

Surgical resection for benign and malignant liver disease

The indications for major hepatic resections in 32 patients and the results are presented. Twelve right lobectomies, eight partial left lobectomies, five left lobectomies, four extended right lobectomies and three partial right lobectomies were performed with a 46% complication rate and an operative mortality rate of 12.5%. Ten primary liver cancers, 12 metastatic lesions, four hemangiomas and six "benign" lesions were removed. Of seven patients with hepatomas, four are alive at an average of 24 months postresection and three have no evidence of recurrence. Of 11 adult patients with metastatic lesions, six are alive at an average of 27 months postresection and three patients have no evidence of recurrence. All four patients with hemangioma are alive at an average of seven years. As in other series, our experience has increased with seven resections prior to 1970 and 25 since. Operative mortality has decreased in that period of time (42% to 4%); however, our complication rate in survivors has remained elevated (25% to 50%). Our experience agrees with others that cautious selection of patients for resection of malignant tumors of the liver can extend survival.

Inhibition of basal and meal-stimulated choleresis by somatostatin

The effect of somatostatin, an inhibitor of release of a number of gastrointestinal and other hormones, on choleresis was investigated in chronic, bile fistula dogs with taurocholate-stabilized bile flow. Somatostatin inhibited both fasting and meal-stimulated choleresis, and bile flows during somatostatin inhibition of both fasting and fed dogs were similar, suggesting a complete suppression of factors causing feeding choleresis. Although a transient decrease in bile salt output was observed, bile salt output was unaffected during most of the period of bile flow inhibition. Hormone suppression by somatostatin, indicated by measurement of serum insulin, occurred over a similar time course as inhibition of choleresis. These observations provide further evidence for physiological humoral regulation of choleresis.

Salmonellae as an index of pollution of surface waters

Screening enrichments of surface water specimens by means of a polyvalent fluorescent antibody reagent for the salmonellae yielded approximately 60% more positive specimens than was obtained by cultural procedures. It is not known what fraction of the excess of fluorescent antibody-positive over culturally positive specimens represents staining of non-salmonellae or non-arizonae as opposed to the staining of non-cultivatable organisms of these two genera. Cotton gauze and rayon-polypropylene fiber swabs were equally sensitive for collecting salmonellae from the streams examined. Tetrathionate enrichment incubated at 41.5 C appeared to be superior to selenite-cystine for isolation of salmonellae from surface waters. Twenty-eight serotypes of Salmonella and two serotypes of Arizona were identified in the 121 positive specimens. In water rated moderately polluted, 65% of all specimens tested were positive; in minimally polluted waters, 38% were positive; and in unpolluted streams, 44% were positive.