Guidelines for Perioperative Care in Bariatric Surgery: Enhanced Recovery After Surgery (ERAS) Society Recommendations

BACKGROUND

During the last two decades, an increasing number of bariatric surgical procedures have been performed worldwide. There is no consensus regarding optimal perioperative care in bariatric surgery. This review aims to present such a consensus and to provide graded recommendations for elements in an evidence-based "enhanced" perioperative protocol.

METHODS

The English-language literature between January 1966 and January 2015 was searched, with particular attention paid to meta-analyses, randomised controlled trials and large prospective cohort studies. Selected studies were examined, reviewed and graded. After critical appraisal of these studies, the group of authors reached a consensus recommendation.

RESULTS

Although for some elements, recommendations are extrapolated from non-bariatric settings (mainly colorectal), most recommendations are based on good-quality trials or meta-analyses of good-quality trials.

CONCLUSIONS

A comprehensive evidence-based consensus was reached and is presented in this review by the enhanced recovery after surgery (ERAS) Society. The guidelines were endorsed by the International Association for Surgical Metabolism and Nutrition (IASMEN) and based on the evidence available in the literature for each of the elements of the multimodal perioperative care pathway for patients undergoing bariatric surgery.

Comparison of lateral thermal spread using monopolar and bipolar diathermy, the Harmonic Scalpel and the Ligasure

BACKGROUND

Electrosurgery for dissection and haemostasis should be associated with minimal thermal spread to surrounding tissues. This study investigated lateral thermal spread following ex vivo application of four commonly utilized instruments.

METHODS

Monopolar and bipolar diathermy (power settings 20, 30 and 40 W), the Harmonic Scalpel and Ligasure (power settings 1, 3 and 5) were studied after application to standardized porcine muscle cuts for 5, 10 or 15 s. Temperatures generated at the tips of the instruments, in the tissues adjacent to the tips and 1 cm away were recorded.

RESULTS

Following a 5-s application at the highest power setting, the highest mean(s.d.) temperatures recorded at the tips of monopolar and bipolar diathermy, Harmonic Scalpel and Ligasure instruments were 78.9(4.1), 41.9(2.2), 47.6(2.5) and 44.2(2.6) degrees C respectively. Temperatures at the instrument tips after use for 15 s remained above 42 degrees C for 55, 25, 15 and 15 s respectively. Applying monopolar diathermy (10 s at 40 W) resulted in a temperature recording of 59.2(2.2) degrees C in tissues 1 cm away from the tip of the instrument.

CONCLUSION

The degree of lateral thermal spread varied with instrument type, power setting and application time. Monopolar diathermy resulted in the highest temperatures and the greatest degree of thermal spread in tissues.

Distribution of alpha- and beta-adrenoceptors in human urinary bladder

1 The distribution of alpha- and beta-adrenoceptors in isolated preparations of human bladder neck and detrusor muscle has been studied.2 Adrenaline caused contraction of the bladder neck which was blocked by phenoxybenzamine but unaltered by propranolol.3 Isoprenaline caused relaxation of the bladder neck which was blocked by propranolol. High concentrations caused contraction which was enhanced by propranolol but blocked by phenoxybenzamine.4 Detrusor muscle was relaxed by isoprenaline and this effect was blocked by propranolol. Phenylephrine caused relaxation of detrusor which was unaffected by phenoxybenzamine; in some cases contraction was produced in the presence of propranolol.5 It is concluded that the bladder neck contains mainly alpha-receptors and the detrusor mainly beta-receptors but both regions posses both types of adrenoceptor.

Aggressive natural killer-cell leukemia mutational landscape and drug profiling highlight JAK-STAT signaling as therapeutic target

Aggressive natural killer-cell (NK-cell) leukemia (ANKL) is an extremely aggressive malignancy with dismal prognosis and lack of targeted therapies. Here, we elucidate the molecular pathogenesis of ANKL using a combination of genomic and drug sensitivity profiling. We study 14 ANKL patients using whole-exome sequencing (WES) and identify mutations in STAT3 (21%) and RAS-MAPK pathway genes (21%) as well as in DDX3X (29%) and epigenetic modifiers (50%). Additional alterations include JAK-STAT copy gains and tyrosine phosphatase mutations, which we show recurrent also in extranodal NK/T-cell lymphoma, nasal type (NKTCL) through integration of public genomic data. Drug sensitivity profiling further demonstrates the role of the JAK-STAT pathway in the pathogenesis of NK-cell malignancies, identifying NK cells to be highly sensitive to JAK and BCL2 inhibition compared to other hematopoietic cell lineages. Our results provide insight into ANKL genetics and a framework for application of targeted therapies in NK-cell malignancies.

Aggressive natural killer-cell leukemia (ANKL) has few targeted therapies. Here ANKL patients are reported to harbor STAT3, RAS-MAPK pathway, DDX3X and epigenetic modifier mutations; and drug sensitivity profiling uncovers the importance of the JAK-STAT pathway, revealing potential ANKL therapeutic targets.

Relationship between neurological and urological status in patients with multiple sclerosis

The relationship between neurological urinary symptoms and urodynamic findings in patients with multiple sclerosis was examined. The duration of multiple sclerosis was significantly longer in patients with urinary symptoms. The presence of urinary symptoms correlated with the severity of the pyramidal or sensory lesions and the total disability score. Cystometrograms revealed detrusor hyperreflexia in 67 per cent of the patients, areflexia in 21 per cent and a normal detrusor in 12 per cent. Somatic dyssynergia was found in 20 of the 39 patients whose examination revealed clear-cut results. Positive correlation was found between urge incontinence and detrusor hyperreflexia, and between hesitancy and detrusor areflexia but no relationship was found between urological symptoms and sphincter function. Analysis of the neurological lesions in relation to the cystometric findings revealed a positive correlation among pyramidal lesions, detrusor hyperreflexia and detrusor areflexia, and between cerebellar lesions and detrusor areflexia. The correlation between detrusor dysfunction and high total disability score disappeared when patients with high pyramidal scores were excluded. No correlation could be detected between somatic dyssynergia and the various neurological lesions.

Oxybutynin versus propantheline in patients with multiple sclerosis and detrusor hyperreflexia

Hyperreflexia is the most common urological finding in patients with multiple sclerosis. A prospective randomized study was done to compare the effectiveness of 2 commonly used drugs, oxybutynin and propantheline. Of the 34 patients entered into the trial 19 were treated with oxybutynin and 15 with propantheline. The urological symptoms (frequency, nocturia, hesitancy, urgency and urge incontinence) were graded according to severity from 0 to 3. Patients with urinary infection were excluded. Urodynamic examination, consisting of cystometrography and electromyography, was performed in all patients before treatment. Both groups of patients had comparable neurological, urological and urodynamic status before treatment. In 4 patients (21 per cent) treated with oxybutynin and in 4 (27 per cent) treated with propantheline side effects were so severe that the treatment had to be discontinued. Symptomatic response to oxybutynin was good in 10 patients (67 per cent), fair in 2 (13 per cent) and poor in 3 (20 per cent). Propantheline produced good symptomatic results in 4 patients (36 per cent), fair in 1 (9 per cent) and poor in 6 (55 per cent). The mean increase in maximum cystometric capacity on cystometrography was significantly larger in the oxybutynin group than in the propantheline group (144 +/- 115 versus 35 +/- 101). Our results indicate that oxybutynin is more effective than propantheline in the treatment of detrusor hyperreflexia in patients with multiple sclerosis.

Sympathetic activity in the proximal urethra in patients with urinary obstruction

The effect of 10 mg. phentolamine intravenously on the urethral pressure profile was studied in male and female patients with lower urinary tract obstruction. A significant decrease of pressure occurred along the whole length of the urethra in both sexes, including the peak pressure zone in the male patient. This zone has been traditionally attributed to the external sphincter. It was concluded that the sympathetically innervated smooth muscle exerts a certain activity along the whole length of the proximal urethra. The phentolamine test may prove to be a useful adjunct to urethral profile studies in patients with lower urinary tract obstruction.

Relative contributions of smooth and striated muscles to the canine urethral pressure profile

Canine urethral pressure profiles were analysed using pharmacological and nerve sectioning techniques. The presence of significant sympathetic and somatic neural components was detected and their locations along the proximal urethra were identified. The neural components peaked at different points in the urethra but overlapped. The non-neural component appeared to form an even base along the whole proximal urethra. It was concluded that in the proximal part of the profile the non-neural and the sympathetic components are significant. The sympathetic component becomes larger in the peak pressure zone. More distally and overlapping with the sympathetic component is the contribution of the striated external sphincter.

Experimental evidence for a central nervous system site of action in the effect of alpha-adrenergic blockers on the external urinary sphincter

The present study was done to test the hypothesis that alpha-adrenoceptor blocking drugs (phentolamine and prazosin) could interfere with somatic control of the external sphincter through an action in the central nervous system. Stimulation of the hypogastric nerve in the chloralose-anesthetized cat caused a urethral constriction which could be antagonized by alpha-receptor blockers. However, the constriction produced by stimulation of the S1 or S2 ventral root was completely resistant to alpha blockade. The drugs therefore had the expected action against sympathetic stimulation of the urethra but had no peripheral effect on the somatic component. The central effect of these drugs was investigated by recording urethral perfusion pressure responses, or compound action potentials on the central cut end of the pudendal nerve, evoked by stimulation of the contralateral pudendal or pelvic nerve. The urethral constriction produced by stimulation of the central cut end of 1 pudendal nerve was antagonized by both prazosin and phentolamine. Action potentials evoked on the pudendal nerve by stimulation of the central cut end of the contralateral pudendal or pelvic nerve were substantially inhibited by prazosin. Phentolamine produced a more variable blockade of the pudendal-pudendal reflex. The results strongly indicate that these alpha-adrenoceptor antagonists and especially prazosin can influence pudendal nerve-dependent urethral responses through a central nervous system action and not through a peripheral mechanism.

Long-term results and complications of augmentation ileocystoplasty for idiopathic urge incontinence in women

OBJECTIVE

To assess the long-term (3-9 years) results of augmentation ileocystoplasty for non-neurogenic female urge incontinence in terms of continence, the need for intermittent self-catheterization and the need for additional or auxiliary treatment, to define the long-term complications and to assess the patients' satisfaction with the outcome.

PATIENTS AND METHODS

The study comprised 51 women who underwent augmentation ileocystoplasty for non-neurogenic urge incontinence between November 1987 and December 1993; 27 patients had associated interstitial cystitis. All patients had exhausted conservative methods, with an unsatisfactory outcome. All patients were interviewed about the results of the procedure, and their charts reviewed and updated with relevant information.

RESULTS

Within a mean (range) follow-up of 75.4 (36-109) months, 27 patients (53%) were completely continent, 13 (25%) had occasional leaks and nine (18%) continued to have disabling urge incontinence frequently requiring pads. Regular self-catheterization was needed by 20 (39%) patients while the rest emptied adequately with no or minimal residual volumes. Additional pharmacotherapy had to be used by 12 (24%) patients. Three patients later developed stress urinary incontinence and were managed with fascial sling procedures. The patch was revised in two patients and excised from four others because they had high residual volumes and uncontrollable infections. Two patients had an ileal conduit diversion for persistent incontinence. The most common complication was recurrent urinary tract infections, seen in 22 patients using intermittent self-catheterization. Mucus retention occurred regularly in 10 patients, six had chronic diarrhoea, four had latent bowel obstruction, one developed a bladder stone, one an incisional hernia and one developed patch necrosis and perforation. Twenty-seven patients (53%) were happy with the outcome of the procedure while 20 (39%) were not; four patients were unsure whether a change had occurred.

CONCLUSION

Augmentation ileocystoplasty is a valuable alternative for women with intractable urge incontinence. However, these patients and their physicians should be aware of its limitations, specifically the possibility that incontinence may persist and the high probability of the need for self-catheterization, with potential subsequent urinary tract infection.

Quantitative assessment of fibrosis and steatosis in liver biopsies from patients with chronic hepatitis C

BACKGROUND

Hepatic fibrosis is one of the main consequences of liver disease. Both fibrosis and steatosis may be seen in some patients with chronic hepatitis C and alcoholic liver disease (ALD).

AIMS

To quantitate fibrosis and steatosis by stereological and morphometric techniques in patients with chronic hepatitis C and compare the results with a control group of patients with ALD. In addition, to correlate the quantitative features of fibrosis with the Ishak modified histological score.

MATERIALS AND METHODS

Needle liver biopsies from 86 patients with chronic hepatitis C and from 32 patients with alcoholic liver disease (disease controls) were analysed by stereological and morphometric analyses using the Prodit 5.2 system. Haematoxylin and eosin and Picro-Mallory stained sections were used. The area fractions (A(A)) of fibrosis, steatosis, parenchyma, and other structures (bile duct and central vein areas) were assessed by stereological method. The mean diameters of fat globules were determined by morphometric analysis.

RESULTS

Significant differences were found in the A(A) of fibrosis, including fibrosis within portal tract areas, between chronic hepatitis C patients and those with ALD (mean (SD): 19.14 (10.59) v 15.97 (12.51)). Portal and periportal (zone 1) fibrosis was significantly higher (p = 0.00004) in patients with chronic hepatitis C compared with the control group (mean (SD): 9.04 (6.37) v 3.59 (3.16)). Pericentral fibrosis (zone 3) occurred in both groups but was significantly more pronounced in patients with ALD. These results correlate well with the modified Ishak scoring system. However, in patients with cirrhosis (stage 6) with chronic hepatitis C the A(A) of fibrosis varied between 20% and 74%. The diameter of fat globules was significantly lower in patients with hepatitis C (p = 0.00002) than the ALD group (mean (SD): 14.44 (3.45) v 18.4 (3.32)). Microglobules were more frequent in patients with chronic hepatitis C than in patients with ALD. In patients with chronic hepatitis C, the fat globules had a zonal distribution in comparison with pan steatosis in ALD.

CONCLUSION

Quantitative, stereological techniques are simple and reliable for evaluating hepatic fibrosis and steatosis in chronic hepatitis C. They are most useful for assessing the origin, location, and the stage of fibrosis. Stereology and morphometry are recommended for the quantitation of fibrosis and steatosis, particularly for the evaluation of new treatment strategies in patients with chronic hepatitis C.

Liver transplantation: intraoperative changes in coagulation factors in 100 first transplants

Six intraoperative blood samples were obtained at intervals from each of 100 individuals undergoing their first liver transplants. The patients fell into the following diagnostic categories: postnecrotic cirrhosis 28, primary biliary cirrhosis 20, sclerosing cholangitis 19, miscellaneous diseases 14, carcinoma/neoplasia 12 and fulminant hepatitis 7. Coagulation factor values in the initial (baseline) blood samples varied by patient diagnosis. In general, all factor levels were reduced except factor VIII:C, which was increased to almost twice normal. The slight intraoperative changes in factors II, VII, IX, X, XI and XII suggested that a steady-state relationship existed between depletion (consumption/bleeding) and repletion (transfusion, transit from extra- to intravascular space), even in the anhepatic state. In contrast, there were rapid and very significant falls in factor VIII and fibrinogen and a less pronounced decrease in factor V, all reaching their nadirs in early to mid-Stage III. The cause of these coagulation changes appears to be activation of the fibrinolytic system.

Carcinoma of the prostate: a critical look at staging

To stage accurately the extent of the disease comprehensive investigations were done on 75 patients with histologically documented carcinoma of the prostate. Estimation of bone marrow acid phosphatase appears to be the most sensitive test to detect blood-borne metastases. Serum acid phosphatase appears to be of little value in the detection of early blood spread and may have a role only in monitoring the effect of treatment on advanced disease. Bone scanning with technetium compounds has the disadvantage of non-specificity but has far greater sensitivity than a skeletal survey. Bone marrow cytology was not rewarding in the detection of early metastatic disease. Pedal lymphangiography is a highly inaccurate method to detect lymphatic spread of carcinoma of the prostate and pelvic lymphadenectomy, when indicated, remains the only truly adequate method to assess lymph node involvement. There was a 37 per cent incidence of metastatic lymph node pathology in 30 patients undergoing this procedure before either radical prostatectomy or deep x-ray therapy. A close correlation was found between stage and grade of disease and incidence of nodal pathology. There was some correlation between degree of nodal involvement and evidence of blood spread as detected by elevated bone marrow acid phosphatase levels. The significance of this finding remains unclear.

Early predictors of anastomotic leaks after colectomy

BACKGROUND

An anastomotic leak after colorectal surgery is associated with significant morbidity and decreased survival. Our aim was to identify the early predictors of anastomotic leaks.

METHODS

The records of patients undergoing restorative resection for colorectal disease from January 2000 to November 2005 were reviewed. Demographics, clinical events, and laboratory parameters were recorded.

RESULTS

A total of 311 patients were included. An anastomotic leak was identified in 25 patients (8%). A leak was suspected and diagnosis confirmed at a mean of 10+/-1 days postoperatively. More respiratory and neurological events occurred in patients with an anastomotic leak (p<0.001). These events occurred early in the postoperative course and were usually the first signs and symptoms of a leak. More patients with a leak had absence of bowel activity by postoperative day 6 compared to patients without a leak (p<0.0001). Elevations of the white blood cell count or temperature were a late finding.

CONCLUSION

The earliest clinical predictors of an anastomotic leak are pulmonary and/or neurological. Awareness of these findings might help in early diagnosis and treatment of an anastomotic leak.

Analysis of imaging modalities, staging systems, and prognostic indicators for renal cell carcinoma

A retrospective analysis of 314 patients with renal cell carcinoma was done focusing mainly on imaging modalities and prognostic significance of tumor stage using both the Robson and TNM systems. Computerized tomography (CT) scan proved to be the most effective modality for staging. Overall staging accuracy was 62 and 68 percent for TNM and Robson staging, respectively, and understaging was more frequent than overstaging. The actuarial five-year survival using the Robson system was 73 percent for Stage A, 68 percent Stage B, 51 percent Stage C, and 20 percent Stage D. The main limitation of the Robson system is the heterogeneity of the Stage C group which includes patients with renal vein and those with nodal involvement with a significant difference in survival. The survival by the TNM system showed no difference in those with T1, T2, T3a and T3b disease but a significant difference in those with T3c or T4a. One hundred sixteen patients (37%) presented with metastatic disease with a median survival of seventeen months (range 2-204) for those with solitary metastasis and six months (range 1-132) for those with multiple metastases (the difference was not statistically significant). Except for anecdotal cases, nephrectomy with or without treatment of the metastases did not seem to affect survival significantly. The presence of spindle cell, alone or in association with clear or granular cell, affected the prognosis adversely. Thirty-one patients had their tumors identified incidentally. Their stage at diagnosis was earlier than the symptomatic group (Stage T1-T2: 77% vs 34%), and there was a significant difference in the disease-free survival at fifty-four months between the two groups (79% vs 57%, respectively).

Alpha-adrenergic agents in urinary disorders of the proximal urethra. Part I. Sphincteric incontinence

Phenylpropanolamine, an alpha receptor stimulant, was found effective in 11 of 13 female and 6 of 7 male patients with sphincteric incontinence. In all the male patients except 1, the incontinence has followed prostatectomy. Side effects occurred in only 1 patient. As a rule, the benficial response depended on the therapy being continued. The results are consistent with the distribution of alpha receptors and their effect in the proximal urethra.

Urethral pressure profile in female stress incontinence

The accuracy of the urethral pressure profile as a measure of sphincteric competence was examined in female subjects. Most profile measurements selected proved to be significantly different in patients with stress incontinence from those in controls. However, the measurement that seemed to have the highest potential for diagnostic accuracy was the maximum closure pressure in the continence zone, recorded with the bladder full and the patient standing. The concept of the continence zone and incorporating the effect of standing were believed to be the main reasons for this high accuracy. The second best measurement was the maximum closure pressure with the bladder full and the patient surpine. To lessen the chances of a diagnostic error it was recommended that both of these measurements should be obtained. The physiological implications of these findings and the clinical role of the urethral pressure profile examination in the assessment of female patients with urinary incontinence are discussed.

The impact of diabetes on current revascularisation practice and clinical outcome in patients with critical lower limb ischaemia

OBJECTIVE

To compare current revascularisation practice and outcome in diabetic and non-diabetic patients presenting with critical limb ischaemia (CLI) to a single vascular surgeon.

METHODS

Data for 113 patients presenting with CLI were collected prospectively over a 3-year period. Forty-four (39%) were diabetic. Treatment was classified as percutaneous angioplasty, arterial reconstruction, primary major amputation, and conservative therapy. Main outcome measures were 30-day mortality, major amputation, survival, and amputation-free survival.

RESULTS

Diabetic patients were more likely to present with gangrene, give a history of angina, be treated with nitrates and statins, and have lower cholesterol levels. No significant differences were found in the initial treatment options between diabetics and non-diabetics: angioplasty 39 vs 26%, surgical revascularisation 34 vs 33%, primary major amputation 9% vs 17%, and conservative treatment 11 vs 19% (p = ns in all). There were eight deaths (7%) within 30-days. At follow-up (1-44 months, median 14 months), rates of major amputation and death for the entire population were 23 and 8%, respectively. The 12-month cumulative survival and amputation-free survival rates were 90 and 72%, respectively. When comparing diabetic to non-diabetic patients, there were no significant differences in the 30-day mortality (6.8 vs 7.2%, p = 0.4), cumulative survival (93 vs 89% at 12 months, log-rank test: 0.00, p = 0.9), amputation-free survival (71 vs 73% at 12 months, log-rank test: 0.00, p = 0.99), and major amputation rates (22.7 vs 23.1% at 12 months, p = 0.96). Similarly, there were no differences in limb salvage rates between diabetic and non-diabetic patients undergoing revascularisation procedures (78 vs 90% at 12 months, log-rank test: 2.04, p = 0.15).

CONCLUSIONS

In current practice, an aggressive multidisciplinary approach in diabetic patients presenting with CLI leads to similar limb salvage, amputation-free survival, mortality, and major amputation rates to those seen in non-diabetic patients. The presence of diabetes should not deter clinicians from attempting revascularisation by means of angioplasty or surgical reconstruction.

Application of Exopolysaccharide-Producing Cultures in Reduced-Fat Cheddar Cheese: Texture and Melting Properties

Textural, melting, and sensory characteristics of reduced-fat Cheddar cheeses made with exopolysaccharide (EPS)-producing and nonproducing cultures were monitored during ripening. Hardness, gumminess, springiness, and chewiness significantly increased in the cheeses as fat content decreased. Cheese made with EPS-producing cultures was the least affected by fat reduction. No differences in hardness, springiness, and chewiness were found between young reduced fat cheese made with a ropy Lactococcus lactis ssp. cremoris [JFR1; the culture that produced reduced-fat cheese with moisture in the nonfat substance (MNFS) similar to that in its full-fat counterpart] and its full-fat counterpart. Whereas hardness of full-fat cheese and reduced-fat cheese made with JFR1 increased during ripening, a significant decrease in its value was observed in all other cheeses. After 6 mo of ripening, reduced fat cheeses made with all EPS-producing cultures maintained lower values of all texture profile analysis parameters than did those made with no EPS. Fat reduction decreased cheese meltability. However, no differences in meltability were found between the young full-fat cheese and the reduced-fat cheese made with the ropy culture JFR1. Both the aged full- and reduced-fat cheeses made with JFR1 had similar melting patterns. When heated, they both became soft and creamy without losing shape, whereas reduced-fat cheese made with no EPS ran and separated into greasy solids and liquid. No differences were detected by panelists between the textures of the full-fat cheese and reduced-fat cheese made with JFR1, both of which were less rubbery or firm, curdy, and crumbly than all other reduced-fat cheeses.

Variability in purified dysfunctional C1(-)-inhibitor proteins from patients with hereditary angioneurotic edema. Functional and analytical gel studies

C1(-)-inhibitor (C1(-)-INH) proteins from normal persons and members of eight different kindred with dysfunctional C1(-)-INH proteins associated with hereditary angioneurotic edema (HANE) were compared with respect to their inhibitory activity against purified preparations of C1s-, plasma kallikrein, activated forms of Hageman factor, and plasmin. Each dysfunctional C1(-)-INH protein showed a unique spectrum of inhibitory activity against these enzymes. Although none of the dysfunctional C1(-)-INH proteins significantly impaired amidolysis by plasmin, all but one inhibited activated Hageman factor. One purified dysfunctional C1(-)-INH (Ta) inhibited purified C1s- to a normal degree. Another C1(-)-INH (Za) had almost seven times as much inhibitory activity as normal C1(-)-INH against activated Hageman factor, but had decreased activity against C1s- and no activity against plasmin. Analyses of mixtures of plasmin and C1(-)-INH proteins in SDS gel electrophoresis revealed variability in the patterns of complex formation and cleavage of dysfunctional proteins after exposure to C1s- and plasmin. Some bound to plasmin and were cleaved, even though none significantly impaired the amidolytic activity of plasmin. Two were cleaved by C1s-, whereas neither normal or other dysfunctional C1(-)-INH were cleaved. Dysfunctional C1(-)-INH proteins from patients with HANE are thus heterogeneous in their inhibitory properties and there must be different structural requirements for the inhibition of the various plasma enzymes that can be regulated by normal C1(-)-INH. The data suggest that in addition to common sites of interactions between these proteases and C1(-)-INH, there are also points of contact that are specific for each protease. Genetic mutations leading to structural changes at some of these sites may have differing effects on the interaction between individual proteases and abnormal C1(-)-INH proteins. These alterations may allow these proteins to serve as probes for structural requirements for inhibitory actions of normal C1(-)-INH.

Factors that influence the incidence of detrusor instability in women

Detrusor instability was examined in 108 women with urinary incontinence. The presence of instability correlated with the symptoms of urge incontinence in 81 of 99 patients. The technique of the cystometrogram also proved important and minor variations significantly altered the incidence. Finally, there seems to be a significant correlation between reduced urethral closure as measured by the urethral pressure profile and instability, suggestive of a causal relationship. An understanding of the factors that affect the incidence of detrusor instability will help to place it in the right perspective in terms of its diagnostic value and pathogenesis.

External sphincter dyssynergia: an abnormal continence reflex

Some of the characteristics of detrusor-external sphincter dyssynergia were examined in 14 patients with traumatic upper motor neuron lesions within 44 weeks of injury. The sacral evoked response latencies of the male patients were shortened at any time after injury. A continence reflex could be demonstrated in most patients at any time after injury. Comparing averaged values for the group at 4-week intervals, resting pressure at the external urethral sphincter and post-void residual volumes reached nadirs at 12 weeks while voiding efficiency peaked at this time. Thus, voiding function appears to be optimal 12 weeks after injury. During reflex detrusor activity, increases in external urethral sphincter electromyographic activity and external urethral sphincter pressure were associated clearly with a positive slope of the intravesical pressure trace, whereas decreases in both parameters were associated with a negative slope. Voiding occurred only during a negative slope. Although propantheline induced detrusor areflexia, episodic peaks in external urethral sphincter pressure and electromyographic activity continued to occur. We propose that external sphincter dyssynergia, which is independent of detrusor contraction, is the continence reflex exaggerated owing to the loss of supraspinal influences. We believe that the multiple patterns of dyssynergia described previously by others are variations, largely owing to technique, of the single pattern we have observed. The observation of synergic-like urethral responses in some patients during a negative slope of the intravesical pressure, even with complete suprasacral spinal lesions, implies existence of a pathway for synergic-like voiding in the spinal cord.

Sympathetic dyssynergia in the region of the external sphincter: a possible source of lower urinary tract obstruction

Voiding cystourethrography demonstrated urethral constriction at the level of the external urinary sphincter in 10 patients with neurological dysfunctions. Ten mg. phentolamine mesylate intravenously alleviated this constriction, permitting better flow and reducing residual urine in 5 patients with a traumatic spinal injury, 2 with transverse myelitis and 1 who had had a cerebrovascular accident. Oral therapy with phenoxybenzamine hydrochloride, used in 7 of the 8 patients, reduced the post-void residual urine and produced improvement in hydronephrosis when present. These observations are consistent with the presence of a significant sympathetic component to obstruction at the region of the external sphincter in certain neurological disorders.

Laparoscopic ventral hernia repair during the learning curve

Large series of laparoscopic ventral hernia repair have shown excellent results. However, published comparative studies have had conflicting outcomes. We retrospectively reviewed the first 29 laparoscopic ventral hernia repairs performed at a VA Medical Center from January 2000 to June 2001. The outcome was compared to that of open repairs performed during the same time period. Outcomes between the groups were similar in all respects, except for the length of stay. The conversion rate for the laparoscopic approach was 13.8%. There was one death in the laparoscopic group due to an unrecognized enterotomy. There were three recurrences in the open group and one in the laparoscopic group with a mean follow up of 13 months. In our series, laparoscopic hernia repair resulted in a shorter hospital stay but no other significant benefits, along with a risk of missed enterotomy. The risk-benefit ratio for this procedure may be high during the learning curve.

Application of exopolysaccharide-producing cultures in reduced-fat Cheddar cheese: cryo-scanning electron microscopy observations

The microstructure of reduced- and full-fat Cheddar cheeses made with exopolysaccharide (EPS)-producing and nonproducing cultures was observed using cryo-scanning electron microscopy. Fully hydrated cheese samples were rapidly frozen in liquid nitrogen slush (-207 degrees C) and observed in their frozen hydrated state without the need for fat extraction. Different EPS-producing cultures were used in making reduced-fat Cheddar cheese. Full-fat cheese was made with a commercial EPS-nonproducing starter culture. The cryo-scanning electron micrographs showed that fat globules in the fully hydrated cheese were surrounded by cavities. Serum channels and pores in the protein network were clearly observed. Young (1-wk-old) full-fat cheese contained wide and long fat serum channels, which were formed because of fat coalescence. Such channels were not observed in the reduced-fat cheese. Young reduced-fat cheese made with EPS-nonproducing cultures contained fewer and larger pores than did reduced-fat cheese made with a ropy strain of Lactococcus lactis ssp. cremoris (JFR1), which had higher moisture levels. A 3-dimensional network of EPS was observed in large pores in cheese made with JFR1. Major changes in the size and distribution of pores within the structure of the protein network were observed in all reduced-fat cheeses, except that made with JFR1, as they aged. Changes in porosity were less pronounced in both the full-fat and the reduced-fat cheeses made with JFR1.