An observational study of the timing of surgery, use of laparoscopy and outcomes for acute cholecystitis in the USA and UK.

BACKGROUND: Evidence supports early laparoscopic cholecystectomy for acute cholecystitis. Differences in treatment patterns between the USA and UK, associated outcomes and resource utilization are not well understood. METHODS: In this retrospective, observational study using national administrative data, emergency patients admitted with acute cholecystitis were identified in England (Hospital Episode Statistics 1998-2012) and USA (National Inpatient Sample 1998-2011). Proportions of patients who underwent emergency cholecystectomy, utilization of laparoscopy and associated outcomes including length of stay (LOS) and complications were compared. The effect of delayed treatment on subsequent readmissions was evaluated for England. RESULTS: Patients with a diagnosis of acute cholecystitis totaled 1,191,331 in the USA vs. 288 907 in England. Emergency cholecystectomy was performed in 628,395 (52.7% USA) and 45,299 (15.7% England) over the time period. Laparoscopy was more common in the USA (82.8 vs. 37.9%; p < 0.001). Pre-treatment (1 vs. 2 days; p < 0.001) and total ( 4 vs. 7 days; p < 0.001) LOS was lower in the USA. Overall incidence of bile duct injury was higher in England than the USA (0.83 vs. 0.43%; p < 0.001), but was no different following laparoscopic surgery (0.1%). In England, 40.5% of patients without an immediate cholecystectomy were subsequently readmitted with cholecystitis. An additional 14.5% were admitted for other biliary complications, amounting to 2.7 readmissions per patient in the year following primary admission. CONCLUSION: This study highlights management practices for acute cholecystitis in the USA and England. Despite best evidence, index admission laparoscopic cholecystectomy is performed less in England, which significantly impacts subsequent healthcare utilization.

Impact of preoperative steroid or immunosuppressant use on short-term outcomes following colectomy in Crohn's disease patients.

BACKGROUND: Evaluating the impact of steroid or immunosuppressants (SI) therapy prior to colectomy in Crohn's disease (CD) patients on postoperative septic and colectomy-specific outcomes using the American College of Surgeons (ACS)-National Surgical Quality Improvement Program (NSQIP)-targeted colectomy database. METHODS: All CD patients undergoing colectomy were retrieved from the 2012-2013 NSQIP-targeted database. Thirty-day postoperative outcomes were compared for patients who were on steroids or immunosuppressants (SI) within the 30 days prior to colectomy to the others using univariable and multivariable analyses. RESULTS: Of 2208 CD patients, 1387 (63%) were on SI. Patients in the SI group were younger, and a greater proportion underwent laparoscopic surgery (p < 0.05). SI use was associated with a higher rate of sepsis (7.6 vs. 5.2%), anastomotic leak (5.6 vs. 3.5%), and return to operating room (6.8 vs. 3.3%). On multivariable analysis, SI was associated with sepsis, septic shock, and anastomotic leak [odds ratio = 1.58, 95% confidence interval 1.09-2.27]. CONCLUSIONS: These results suggest that SI use within 30 days of colectomy is associated with a higher rate of sepsis and septic shock and anastomotic leak in CD patients. Withholding SI prior to surgery, or the selective use of an ostomy to mitigate the consequences of a leak and hence sepsis need due consideration prior to surgery.

30-day mortality after elective colorectal surgery can reasonably be predicted.

BACKGROUND: The aim of the present study was to develop a clinically relevant, accurate and usable risk assessment scoring system solely for colorectal cancer patients undergoing elective resection. METHODS: All colorectal resections for colorectal cancer 2006-2012 were identified from the American College of Surgeons Quality Improvement Program. Independent risk factors for 30-day mortality after elective surgery were identified using univariable and multivariable logistic regression. A points-calculator based on factors most strongly associated with mortality and accurately predicting risk of mortality was developed. RESULTS: Fifty-nine thousand nine hundred eighty-six patients underwent elective colorectal cancer surgery, and 1096 (1.8 %) died within 30 days. On multivariable analysis, the strongest risk factors for mortality were age ≥65 years [odds ratio (OR) 2.17, 95 % confidence interval (CI) 1.61-2.92], American Society of Anesthesiologists score ≥3 (OR 1.77, 95 % CI 1.29-2.42), renal failure (OR 3.15, 95 % CI 1.01-9.77), disseminated cancer (OR 2.56, 95 % CI 1.96-3.35), hypoalbuminemia (OR 2.84, 95 % CI 2.21-3.65), preoperative ascites (OR 3.17, 95 % CI 2.07-4.87), heart failure (OR 2.08, 95 % CI 1.35-3.20) and functional status (OR 2.05, 95 % CI 1.56-2.70). A model that accurately predicted risk of mortality was created using forward stepwise logistic regression and externally validated (area under the curve 0.826). This allowed for development of an eight-factor predictive score; maximum points conferred mortality of 96.1 % (p < 0.0001). CONCLUSIONS: A simple preoperative scoring system predicting 30-day mortality with good capability may allow better preoperative risk assessment, optimization and decision-making.

Benefit of mechanical bowel preparation prior to elective colorectal surgery: current insights.

BACKGROUND: Back in the 1970s, the administration of oral antibiotics combined with mechanical bowel preparation prior to colorectal surgery was considered standard procedure and adopted widely. Subsequent evidence suggested that bowel cleansing was unnecessary, even harmful, and hence was abandoned. Most recent evidence, however, suggests that full preparation significantly improves a spectrum of colectomy-specific postoperative outcomes. PURPOSE: The purpose of this review was to describe existing literature regarding the optimal bowel preparation regimen prior to elective colorectal resection. In addition, we evaluate the available evidence on each component-oral antibiotics, mechanical bowel preparation and intravenous antibiotics, with regard to short-term postoperative outcomes. CONCLUSIONS: Current best evidence suggests that colorectal resection should be preceded by a combination of oral antibiotics, mechanical bowel preparation and intravenous antibiotics at induction. Further randomized controlled trials are required due to a paucity of level 1 evidence.

The cutaneous course of deep inferior epigastric perforators: implications for flap thinning.

BACKGROUND: The deep inferior epigastric artery (DIEA) perforator flap is frequently used for autologous breast reconstruction following mastectomy. Thinning of the flap is often performed to debulk the flap of excess fatty tissue, such as in partial mastectomy defects. Thinning may disrupt the blood supply to the flap and compromise viability, however adequate guidelines for thinning are lacking from the literature. METHODS: Clinical and anatomical studies were concurrently undertaken to explore the cutaneous course of perforators as a guide to flap thinning. Twenty consecutive patients undergoing DIEA perforator flap breast reconstruction underwent preoperative computerised tomography angiography (CTA), and a cadaveric study was also undertaken, in which six fresh, whole abdominal walls underwent CTA. All perforators greater than 2 mm were analysed for their cutaneous course. RESULTS: In all cases, perforators emerged from the anterior rectus sheath and traversed an oblique, but direct course through the deep layer of adipose tissue, before reaching Scarpa's fascia. Branching of perforators occurred in two planes of the superficial adipose layer: just superficial to Scarpa's fascia (the fascial plexus) and in the subdermal plexus. CONCLUSION: Thinning of DIEA perforator flaps can only be performed safely deep to Scarpa's fascia. Thinning performed superficial to Scarpa's fascia threatens the intrinsic blood supply to the flap.

Phylogenetic and pathotypic similarities between Escherichia coli isolates from urinary tract infections in dogs and extraintestinal infections in humans.

Seventeen Escherichia coli isolates from dogs with urinary tract infection (UTI) were characterized with respect to phylogenetic background and virulence genotype and were compared with the E. coli reference (ECOR) collection and with human clinical isolates with similar serotypes from patients with diverse extraintestinal infections. Most of the canine urine isolates were from (virulence-associated) E. coli phylogenetic groups B2 or D, expressed papG allele III, and exhibited numerous other putative virulence genes that are characteristic of human extraintestinal pathogenic E. coli (ExPEC). Close phylogenetic and pathotypic correspondence was documented within 5 clonal groups among individual canine and human isolates, including archetypal human ExPEC strains CFT073 (O6:K2:H1), 536 (O6:K15:H31), and J96 (O4:K-:H5). These findings suggest that canine UTI isolates, rather than being dog-specific pathogens, as previously suspected, may pose an infectious threat to humans. Commonality between canine and human ExPEC has potentially important implications for disease prevention, antibiotic resistance avoidance, and studies of pathogenesis.

Effect of antemortem feeding regimes on bacterial numbers in the stomachs and ceca of pigs.

Three groups, each of 45 pigs, were either not fasted, fasted for 15 h during lairage at the abattoir, or fasted for 15 h before dispatch from the piggery to the abattoir. Three subgroups, each of 15 pigs from each group, were held at the abattoir for additional times of either 0 to 1 h, 2 to 3 h, or 4 to 5 h. Immediately after slaughter, stomach and cecal contents were collected for pH measurement and enumeration of coliforms, Escherichia coli biotype 1 and lactic acid bacteria (LAB). Stomach pH changed from 4.1 to 3.1 as additional abattoir holding time increased from 0 to 1 h to 4 to 5 h but was unaffected by feed withdrawal (mean pH, 3.5). Cecal pH (range 6.4 to 7.2) increased in response to both treatments. Coliform and E. coli biotype 1 numbers in the stomach, means 4.6 and 4.5 log CFU/g, respectively, were not affected by feed withdrawal but decreased 0.8 log units as additional abattoir holding time increased from 0 to 1 to 4 to 5 h. LAB in the stomach decreased in response to both feed withdrawal and holding at the abattoir. Cecal numbers of coliforms and E. coli biotype 1 increased 0.8 and 1.0 log units to 7.8 and 7.6 log CFU/g, respectively, as a result of feed withdrawal, and 0.6 log units to 7.6 and 7.5 log CFU/g, respectively, as additional abattoir holding time increased to 4 to 5 h. The LAB in the cecum (mean 9.4 log CFU/g) increased slightly with increasing abattoir holding time. In the event of release of stomach or cecal contents onto the meat during carcass dressing, larger numbers of E. coli per g would be released from the ceca and fewer per g from the stomachs of pigs that have had feed withdrawn as compared to pigs not subjected to feed withdrawal.

Fall and winter hormone concentrations related to stress in pigs identified as normal and carrier for stress susceptibility.

Stress is associated with significant losses in the swine industry. Seasonal changes have been shown to affect stress resistance in several species of animals. In the present study, we examined the effect of two seasons (fall or winter) on plasma insulin, cortisol, and adrenocorticotrophin hormone (ACTH) levels from fasted normal and carrier pigs for stress susceptibility when submitted to a blood-sampling stressor between 10:00 and 11:00. Comparisons were made of 10 diurnally active normal (NN) and 8 carrier (Nn) pigs reared in the fall to 9 NN and 10 Nn pigs reared in the winter. The light-dark cycle throughout the period of the experiment was 10 h light/14 h dark, with lights on from 07:00 to 17:00. Feed consisted of the traditional western Canadian swine ration consumed ad libitum. Results revealed significant season-by-genotype interactions for plasma insulin and ACTH concentrations in response to the blood-sampling stressor. The normal pigs displayed a significantly lower plasma insulin level during winter compared to the fall season. Plasma ACTH of normal pigs was 18% lower in the winter compared to the fall season, although this difference was not statistically significant. The carrier genotype, on the other hand, demonstrated higher plasma insulin concentration and lower plasma ACTH concentration in the winter compared to the fall season. Furthermore, there was a main genotype effect in plasma cortisol concentration such that the carrier pigs experienced a greater level compared to the normal genotype. Similarly, the carrier pigs had a more acute ACTH response to the blood-sampling stressor compared to the normal pigs during the fall season. Results have demonstrated that these two seasons of the year affect the response of both genotypes to a blood-sampling stressor, with the carrier genotype experiencing a more intense stress reaction in the fall season. These results further contribute to the recent research indicating that carrier pigs for stress susceptibility have a unique stress response.

Disruption of visual short-term memory by changing-state auditory stimuli: the role of segmentation.

Typically, serial recall performance can be disrupted by the presence of an irrelevant stream of background auditory stimulation, but only if the background stream changes over time (the auditory changing-state effect). It was hypothesized that segmentation of the auditory stream is necessary for changing state to be signified. In Experiment 1, continuous random pitch glides failed to disrupt serial recall, but glides interrupted regularly by silence brought about the usual auditory changing-state effect. In Experiment 2, a physically continuous stream of synthesized vowel sounds was found to have disruptive effects. In Experiment 3, the technique of auditory induction showed that preattentive organization rather than critical features of the sound could account for the disruption by glides. With pitch glides, silence plays a preeminent role in the temporal segmentation of the sound stream, but speech contains correlated time-varying changes in frequency and amplitude that make silent intervals superfluous.

The effect of ractopamine on myofibre distribution and morphology and their relation to meat quality in swine.

One hundred and twenty-eight purebred Lacombe pigs (equal number of barrows and gilts) were assigned to one of four treatments at 64 kg and fed a commercial grower-finisher diet ad libitum to which ractopamine (RAC) was incorporated (0, 10, 15 or 20 mg kg(-1)). Pigs were slaughtered at 100 kg. Histological samples were collected from the semimembranosus (SM) and the psoas major (PM) muscles from the 0 and 20 mg kg(-1) RAC groups. Meat quality and muscle composition data were collected for all pigs. A significant 3-way interaction for muscle weight involving treatment, muscle and gender (P = 0·01) indicated that for the SM, gilts appeared to respond to RAC at a lower level of incorporation (10 mg kg(-1)) than barrows. Despite these differences in response at the gross muscle level, responses were similar at the cellular level for both muscles. The proportion of red fibres did not change (P = 0·21), the proportion of intermediate fibres decreased (P = 0·01) and the proportion of white muscle fibres increased (P = 0·02) in the mg kg(-1) RAC group compared to the controls. In addition, when compared to controls, average fibre diameters in the 20 mg kg(-1) RAC group remained constant in the red fibres, and increased significantly in both the intermediate and white fibres (P = 0·01 and 0·02, respectively). Over both muscles Kramer Press values were significantly higher (P = 0·030 in the RAC-fed pigs than in the controls. Incorporation of RAC into the diet did not result in any changes to crude protein or total and soluble hydroxyproline levels. Crude fat tended to increase in the 15 mg kg(-1) RAC treatment in the SM and decreased in the 20 mg kg(-1) RAC treatment in the PM. The shift in fibre type, and the associated changes in fibre size, may contribute to the increased shear values found in RAC-fed pigs.

Cryogenic chilling of pork carcasses: Effects on muscle quality, bacterial populations and palatability.

Two experiments were conducted to determine the effects of cryogenic chilling on the carcass shrinkage, meat quality, bacterial condition and palatibility of pork. In experiment I, pork sides were chilled at 1°C (n = 20), or immersed in liquid nitrogen (LN) for 1 or 3 min prior to placement in a 1°C cooler. Muscle temperature in the loin was significantly lower at 2 and 6 h post mortem in treated compared to control sides, and loin muscle pH was higher (P < 0·05) at 6 h post mortem in sides immersed for 3 min in LN. Carcass side shrinkage was reduced from 29·3 g kg(-1) in control sides to 20·9 and 13·5 g kg(-1) in sides dipped in LN for 1 and 3 min. Chilling treatment had no significant effect on the survival of mesophilic bacteria on carcass sides, on meat colour, drip loss, protein solubility or sarcomere length, but sides dipped for 1 min in LN has a higher muscle shear value than control sides. In experiment II, carcass sides from halothane positive (H+) and negative (H-) pigs were conventionally chilled (n = 49), immersed in LN for 3 min (n = 23), or electrically stimulated and chilled in LN for 3 min (n = 26). Similar results for temperature, pH, colour, protein solubility and drip loss in loin muscle were found to those in experiment I. Laboratory taste panel results showed that chilling treatment had no effect on palatability. Genotype produced meaningful differences in most palatability attributes with H+ pigs having less tender, less juicy and less desirable flavour than pork from H- pigs. Laboratory studies with inoculated fresh muscle slices showed that a 3 min immersion in LN resulted in a 10-fold reduction in the aerobic spoilage pseudomonads, but effects upon other spoilage bacteria and potential human pathogens were less pronounced. It was concluded that cryogenic chilling using LN reduced carcass shrinkage during cooling, but had no consistent effects on meat quality, palatability or bacterial numbers on the carcass. In contrast, genotype had a significant effect on most pork quality and palatability attributes.

Stunning and shackling influences on quality of porcine Longissimus dorsi and Semimembranosus muscles.

Seventy-one barrows of three porcine genotypes (nn, Nn and NN genotypes with respect to halothane) were electrically stunned on the right side and randomly assigned to one of three treatments during the bleeding process (prone, PR; shackled left, SL; or shackled right, SR) to investigate the influence of both shackling and stunning on ultimate meat quality. PR carcasses had less side-to-side variation in 40 min pH than either SL or SR carcasses. Shackling contributed to a decreased 40 min pH in the semimembranosus (SM) and posterior longissimus dorsi (PL). The effects of stunning appeared to be additive when combined with shackling, tending to lower pH in the mid-longissimus dorsi (ML; P <- 0·10). The 'free' side of the shackled carcass also had significantly lower 40 min pH in the ML, PL and SM locations when compared to PR sides. Genotype had no influence on shackling since there was no treatment by genotype interactions. Despite significant effects on post-mortem metabolism (indicated by the differences in 40 min pH) shackling alone had little influence on overall ultimate meat quality of the carcass. Depending on the sampling location, soluble protein and L (∗) and b (∗) values varied among treatments. Shear force and a (∗) values were similar among treatments, but PR and SL carcasses had significantly lower expressible juice and drip loss compared to SR carcasses. These results suggest that, although shackling alone has little effect on meat quality, in combination with electrical stunning, shackling can lead to a decrease in meat quality.

The effects of differences in inherent muscle quality and frozen storage on the flavor and texture profiles of pork loin roasts.

Complete flavor and texture profiles on pork loins from 118 carcasses revealed the following findings: (1) freezing, storing and thawing pork loins produced a slight tenderizing effect by making them less cohesive and easier to chew; permitted greater moisture release during chewing, thereby, slightly increasing the juiciness; resulted in a breakdown to more appropriate residual particles which resulted in a more appropriate, well balanced and blended texture; but resulted in a less appropriate and well balanced flavor; (2) pork with normal muscle quality had a firmer, more elastic, and cohesive texture which was stringier, more fibrous, and harder to compress, resulting in a slower breakdown to particles which tended to be fibrous, grainy and mealy; (3) the PSE condition appeared to result in a drier texture with less moisture and fat being released during mastication and a greater amount of moisture being absorbed from the mouth; (4) the DFD condition appeared to result in a juicier texture with greater amounts of fat and moisture being released into the mouth during mastication and a softer texture which was less cohesive, fibrous, and stringy and easier to chew, but as the DFD condition became extreme the texture became excessively soft, crumbly and mushy resulting in a relatively large proportion of small mealy and/or mushy particles which detracted from the texture amplitude; (5) the PSE condition resulted in a predominance of sour notes which detracted from the flavor amplitude, and possibly resulted from more extensive accumulation of lactic acid during postmortem glycolysis; and (6) the DFD condition resulted in a predominance of porky, sweet, and fatty character notes which enhanced the flavor amplitude but as the DFD condition became extreme, more character notes contributing to off-flavors were detected, a portion of which were apparently due to sex taint. Present findings clearly document the influence of differences in inherent muscle quality on palatability properties of pork loins and aid in resolving the controversy that presently exists within the literature regarding the effects of freezing, frozen storage, and thawing on pork palatability. However, further research will be required to document the impact of such influences on consumer acceptance.

Effects of pork muscle quality on bacterial growth and retail case life.

The effects of muscle quality (PSE, normal, DFD) upon the bacteriology and retail case life of pork chops were determined. Pork loin chops were processed from boneless backs after 90 days of frozen storage at -30°C. Variation in bacterial numbers was due to a highly significant (p < 0·001) storage time by muscle quality interaction. During simulated retail display, total psychrotrophs, Pseudomonas spp., Brochothrix thermosphacta and Enterobacteriaceae were lowest on PSE pork and highest on DFD pork in comparison to normal pork. Differences in bacterial densities were due to a longer lag phase in PSE pork and a shorter lag phase in DFD pork than in normal pork. Of the three muscle quality groups, DFD was most susceptible to the development of spoilage odours, while PSE pork was most sensitive to deterioration in appearance.

The effects of various post-mortem treatments on certain physical and sensory properties of three different bovine muscles.

Sixty crossbred steers with chronological ages approximating 15 months, carcass weights approximating 270 kg and subcutaneous fat thickness measurements approximating 1·2 cm, were maintained for approximately 210 days on a constantly increasing concentrate ration (13 to 75%, according to NAS nutrient requirements for beef cattle; NAS, 1976). These animals were utilized to evaluate the effects of delayed chilling, hot-boning and electrical stimulation on certain physical, histological, biochemical and sensory properties of three different muscles (Semimembranosus, SM; Longissimus dorsi, LD; and Triceps brachii, TB). Results indicated that neither delayed chilling nor electrical stimulation produced consistent meaningful alterations in any of the physical, cooking or palatability attributes evaluated. However, early post-mortem excision of muscle (hot-boning) consistently produced toughening in all of the muscles evaluated. This was observed to a much greater degree in the TB than in either the SM or LD. Based upon sarcomere length determinations, such toughening could be attributed to cold shortening only in the TB. Electrical stimulation of excised muscle was ineffective in preventing or offsetting this toughening. The delayed chilling treatment imposed (2 h at 12·5°C) was ineffective in enhancing potential effects of electrical stimulation on tenderness.