Acute surgical unit safely reduces unnecessary after-hours cholecystectomy

Introduction

The acute surgical model has been trialled in several institutions with mixed results. The aim of this study was to determine whether the acute surgical model provides better outcomes for patients with acute biliary presentation, compared with the traditional emergency surgery model of care.

Methods

A retrospective review was carried out of patients who were admitted for management of acute biliary presentation, before and after the establishment of an acute surgical unit (ASU). Outcomes measured were time to operation, operating time, after-hours operation (6pm – 8am), length of stay and surgical complications.

Results

A total of 342 patients presented with acute biliary symptoms and were managed operatively. The median time to operation was significantly reduced in the ASU group (32.4 vs 25.4 hours, p=0.047), as were the proportion of operations performed after hours (19.5% vs 2.5%, p<0.001) and the median length of stay (4 vs 3 days, p<0.001). The median operating time, rate of conversion to open cholecystectomy and wound infection rates remained similar.

Conclusions

Implementation of an ASU can lead to objective differences in outcomes for patients who present with acute cholecystitis. In our study, the ASU significantly reduced time to operation, the number of operations performed after hours and length of stay.     

A new variant of type II von Willebrand disease with aberrant multimeric structure of plasma but not platelet von Willebrand factor (type IIF)

A patient with a lifelong bleeding disorder was diagnosed as having Type II von Willebrand disease. The larger multimers of von Willebrand factor were absent from her plasma but present in platelets. A high- resolution electrophoretic technique was used to study the complex structure of individual von Willebrand factor multimers. In normal plasma, each multimer could be resolved into five bands: a more intense central one and four less intense, two moving faster and two slower than the central band. In normal platelets, each multimer could also be resolved into five bands. The central one had a mobility similar to that in plasma, whereas the four satellite bands had a mobility that differed from that of the corresponding plasma bands. In the patient, platelet von Willebrand factor antigen content and ristocetin cofactor activity were normal, and von Willebrand factor showed the same structure of individual multimers as seen in normal platelets. On the other hand, plasma von Willebrand factor antigen and ristocetin cofactor activity were decreased, and the structure of individual von Willebrand factor multimers was different from that of normal plasma and similar to that seen in normal and patient's platelets. After infusion of 1-deamino-8-D-arginine vasopressin, the largest von Willebrand factor multimers, as well as new satellite bands with a mobility similar to those in normal plasma, appeared in the patient plasma, and the levels of von Willebrand factor antigen and ristocetin cofactor activity became normal. Yet no relevant change in the prolonged bleeding time was observed. This new variant of von Willebrand disease, therefore, is characterized by the presence of a dysfunctional von Willebrand factor molecule that exhibits unique structural abnormalities in plasma but appears to be normal in platelets. The designation of Type IIF is proposed for this type of von Willebrand disease in accordance with the terminology that has been previously used.     

Infants use relative numerical group size to infer social dominance

Detecting dominance relationships, within and across species, provides a clear fitness advantage because this ability helps individuals assess their potential risk of injury before engaging in a competition. Previous research has demonstrated that 10- to 13-mo-old infants can represent the dominance relationship between two agents in terms of their physical size (larger agent = more dominant), whereas younger infants fail to do so. It is unclear whether infants younger than 10 mo fail to represent dominance relationships in general, or whether they lack sensitivity to physical size as a cue to dominance. Two studies explored whether infants, like many species across the animal kingdom, use numerical group size to assess dominance relationships and whether this capacity emerges before their sensitivity to physical size. A third study ruled out an alternative explanation for our findings. Across these studies, we report that infants 6–12 mo of age use numerical group size to infer dominance relationships. Specifically, preverbal infants expect an agent from a numerically larger group to win in a right-of-way competition against an agent from a numerically smaller group. In addition, this is, to our knowledge, the first study to demonstrate that infants 6–9 mo of age are capable of understanding social dominance relations. These results demonstrate that infants’ understanding of social dominance relations may be based on evolutionarily relevant cues and reveal infants’ early sensitivity to an important adaptive function of social groups.Competition for valuable resources such as mates, food, and territory (1) is commonplace across the animal kingdom. To minimize the cost of fighting (e.g., energy spent and personal injury or death), natural selection appears to have favored the emergence of cognitive adaptations that help individuals predict whether they stand a chance against an opponent (2–5). For example, many species, including ants, bees, birds, chimpanzees, and humans, appear to represent dominance relationships among conspecifics and use this information to decide whether to engage in or avoid a physical conflict (6–10). One such cue often associated with dominance ranking is physical size, with larger individuals often benefiting from greater strength and power over smaller individuals. Natural selection has also favored adaptations that exploit this inference, such that under threat, certain species adopt postures that make them appear bigger (11, 12) in order to intimidate an opponent.Underscoring the possibility that representations of social dominance may be part of humans’ evolved psychology, recent evidence has demonstrated that preverbal human infants infer social dominance relationships by comparing the physical size of two competing agents (13). In this earlier study, infants were introduced to two agents (one twice as large as the other), each with the goal of crossing to the opposite side of a platform. When both agents tried to cross the platform at the same time, their paths conflicted. Infants were shown two scenarios: one in which the larger agent yielded to the smaller agent, and one in which the smaller agent yielded to the larger agent. Although 10–13 mo olds expected a smaller agent to yield to a larger agent, younger infants (8–9 mo) failed to show any systematic belief about which agent should prevail. Therefore, only older infants were able to use the relative physical size of two competing agents to infer which one would get the right of way.Because younger infants did not reliably use physical size as a cue to social dominance, it remains unclear whether the younger infants were incapable of representing dominance relationships in general, or if they lacked sensitivity to this particular cue. To address this issue, the present study examined whether infants’ understanding of social dominance extends to cues beyond physical size—namely, to numerical group size, and if so, whether such a sensitivity emerges earlier in development.For many group-living animals, including social insects (7), wolves (14), hyenas (15), lions (16), primates (6), and human children and adults (5, 10), the ability to infer social dominance by assessing the numerical size of one’s own group relative to another is particularly important for survival (15, 17). The importance of this capacity to evaluate one’s own group size relative to another is illustrated by groups of chimpanzees patrolling their territory borders. To advertise the numerical strength of their group to others (18, 19) and deter opposing groups from approaching (20, 21), both males and females will engage noisy pant-hoot calling. In general, both chimpanzees and lions are more likely to approach if they outnumber intruders, but will stay silent and refrain from engaging in intergroup conflict if they do not (6, 16, 22, 23). Consequently, a group’s decision to engage in competition is more likely to occur if there are more individuals in one’s own group than in the opposing group (22, 24). Further, the relationship between numerical group size and inferences about social dominance has also been recently observed among children ages 6–8 y (5). School-aged children predicted that alliance strength would determine the likelihood of success in a conflict, such that two individuals aligned together were expected to win against a single individual. Coupled with the evidence reviewed from behavioral ecology, numerical group size may serve as an evolutionarily relevant cue to social dominance that humans are sensitive to within the first few years of life.Indeed, if young human infants have core knowledge of social relationships, as some have argued (13, 25), along with the capability to track the numerical size of small groups (26), it is possible that infants may be able to draw on both capacities to support inferences about the social dominance relationship between groups that differ in numerical size. If infants infer that individuals from larger groups are more dominant than individuals from smaller groups, this would demonstrate that infants’ understanding of social dominance can extend beyond the direct relationship between two competing individuals. Specifically, such a finding may shed light on whether infants already have an understanding of how social alliances operate—namely, that group members may help their own during a conflict, which confers a benefit to having more alliance members in close proximity during a conflict (10).Here, we explored whether infants can infer the dominance relationship between two agents from groups that differ in numerical size by modifying the methodology designed by Thomsen et al. (13). In our study, infants were first introduced to two groups that differed in numerical size (but equated for total surface area) and color. Next, infants were familiarized to an agent from each group independently achieving their goal of crossing a platform. When both of these agents attempted to cross the platform simultaneously, they bumped into one another. Therefore, the only way an agent could continue along their goal path was if one agent yielded to the other by moving out of the way.In study 1, we investigated whether 9- to 12-mo-old infants use numerical group size as a cue to social dominance. In study 2, we examined whether 6- to 9-mo-old infants (who have not yet been shown to represent social dominance relationships between individuals) would also be sensitive to the cue of numerical group size. Infants in studies 1 and 2 viewed the same sequence of events.     

Cervical spine in Treacher Collins syndrome

Treacher Collins syndrome is a congenital syndrome with characteristic craniofacial malformations, which are well described in the literature. However, the presence of cervical spine dysmorphology in this syndrome has been minimally described. This study reviews cervical spine radiographs of 40 patients with Treacher Collins syndrome. In this sample, 7 of 40 patients displayed cervical spine anomalies, with 3 of these patients displaying multiple cervical spine anomalies. The patterns of spinal anomalies were variable, suggesting that the underlying genetic mutation has variable expressivity in cervical spine development as it does elsewhere in the craniofacial skeleton.     

Sudden cardiac death in hemodialysis patients: a comprehensive care approach to reduce risk

Sudden cardiac death is a major problem in hemodialysis patients, and our understanding of this disease is underdeveloped. The lack of a precise definition tailored for use in the hemodialysis population limits the reliability of epidemiologic reports. Efforts should be directed toward an accurate classification of all deaths that occur in this vulnerable population. The traditional paradigm of disease pathophysiology based on known cardiac risk factors appears to be inadequate to explain the magnitude of sudden cardiac death risk in chronic kidney disease, and numerous unique cofactors and exposures appear to determine risk in this population. Well-designed cohort studies will be needed for a basic understanding of disease pathophysiology and risk factors, and randomized intervention trials will be needed before best management practices can be implemented. This review examines available data to describe the characteristics of the high-risk patient and suggests a comprehensive common sense approach to prevention using existing cardiovascular medications and reducing and monitoring potential dialysis-related arrhythmic triggers. Other unproven cardiovascular therapies such as implantable cardioverter defibrillators should be used on a case-by-case basis, with recognition of the associated hazards that these devices carry among hemodialysis patients.     

The use of self-expanding metal stents in the management of large bowel obstruction and malignant fistulating disease: a large district general experience

The following abstracts won prizes at the 153rd East Midlands Surgical Society meeting held on 9 November 2012 at Leicester General Hospital. First prize was won by George et al. The paper by Ogunbiyi et al was placed second and the paper by Khanna et al was placed third.     

Does Preoperative 25-Hydroxyvitamin D Status Significantly Affect the Calcium Kinetics after Total Thyroidectomy?

Background

Although previous studies have suggested that low preoperative 25-hydroxyvitamin D (25-OHD) is a risk factor for hypocalcemia after total thyroidectomy, the impact of preoperative 25-OHD on calcium (Ca)/parathyroid hormone (PTH) kinetics in the immediate postoperative period remains unclear. The study compared the postoperative Ca/PTH kinetics between different preoperative 25-OHD levels.

Patients

A total of 281 patients who underwent a total thyroidectomy were analyzed. Serum Ca was measured preoperatively within 1 h after surgery (Ca-D0) and on the following morning (Ca-D1). Preoperative 25-OHD was also measured after overnight fasting while postoperative PTH was checked at skin closure on day 0 (PTH-D0) and on the following morning on day 1 (PTH-D1). The Ca/PTH kinetics were compared between three groups (group I: preoperative 25-OHD < 10 ng/mL; group II: 25-OHD = 10–20 ng/mL; group III: 25-OHD > 20 ng/mL).

Results

Group I had significantly lower preoperative Ca (p = 0.016) and Ca-D0 (p = 0.036) but higher PTH-D1 (p = 0.015) than groups II and III. PTH-D0, Ca-D1, and the rate of clinically significant hypocalcemia were similar in the three groups. Group I had a significantly smaller Ca drop (?0.02 vs. 0.01 and 0.02 mmol/L, p = 0.011) and a tendency for a significantly smaller PTH drop (0.4 vs. 0.5 and 1.0 pmol/L, p = 0.073) than groups II and III. PTH-D1 (OR = 1.550) and 25-OHD (OR = 0.958) were independent factors for Ca drop from day 0 to day 1.

Conclusions

Although group I began with lower serum Ca, those patients tended to have a greater PTH response to Ca drop and so preoperative 25-OHD did not significantly affect the overall Ca kinetics from preoperative to day 1.     

How Useful Are Perioperative Biochemical Parameters in Predicting the Duration of Calcium and/or Vitamin D Supplementation After Total Thyroidectomy?

Background

Oral calcium and calcitriol are often prescribed after total thyroidectomy to avoid biochemical and/or symptomatic hypocalcemia. We aimed to identify independent perioperative factors that correlated with the duration of calcium and/or calcitriol supplementation after total thyroidectomy.

Methods

Of 271 eligible patients, 48 (17.7 %) required calcium and/or calcitriol supplements on discharge. Patients were gradually weaned from the supplementation by one surgeon according to a biweekly algorithm based on serum calcium (Ca). Duration of supplementation was calculated from the date of operation to the date of ceasing all supplementation without biochemical hypocalcemia (i.e., serum adjusted Ca ≥8.44 mg/dL). The Cox regression analysis was performed to identify independent perioperative factors for duration of supplementation. The best cut-off value for these independent factors was determined by the receiver characteristic curve.

Results

In the multivariate analysis, parathyroid hormone (PTH) at skin closure (PTH-SC) (RR 1.742, 95 % CI 1.080–2.810) and on postoperative day 1 adjusted Ca (Ca-D1) (RR 77.526, 95 % CI 3.600–1669.57) were the only two independent determinants for shorter duration before ceasing all supplementation. The best cut-off values in predicting supplementation ≥6 months for PTH-SC and Ca-D1 were 7.08 pg/mL (sensitivity = 100 %, specificity = 60.5 %, PPV = 40.0 % and NPV = 100 %) and 7.88 mg/dL (sensitivity = 90.0 %, specificity = 55.3 %, PPV = 34.6 % and NPV = 95.5 %), respectively.

Conclusions

Both PTH-SC and Ca-D1 were independently associated with the duration of supplementation after total thyroidectomy. Almost all patients with PTH-SC ≥7.08 pg/mL or Ca-D1 ≥7.88 mg/dL did not require supplementation ≥6 months whereas about one third of patients with PTH-SC <7.08 pg/mL or Ca-D1 <7.88 mg/dL required supplementation ≥6 months.     

Postablation Stimulated Thyroglobulin Level is an Important Predictor of Biochemical Complete Remission after Reoperative Cervical Neck Dissection in Persistent/Recurrent Papillary Thyroid Carcinoma

Background

The efficacy of reoperative cervical neck dissection (RND) in achieving biochemical complete remission (BCR) (or postreoperation stimulated thyroglobulin [sTg] of <0.5 ng/mL) remains unclear in persistent/recurrent papillary thyroid carcinoma (PTC). We hypothesized that lower postablation sTg levels would indicate a higher rate of BCR after RND. Our study examined the association between postablation sTg and BCR after one or more RNDs.

Methods

Of 199 patients who underwent RND, 81 patients were eligible. The postablation sTg levels (≤2 and >2 ng/mL) were correlated with the postreoperation sTg levels after RNDs. Patients’ clinicopathological characteristics, operative findings, and subsequent RNDs were compared between those with BCR after RNDs and those without.

Results

Those with postablation sTg levels of ≤2 ng/mL had significantly higher BCR rate after the first RND (77.8 vs. 5.6 %, p < 0.001), overall BCR after one or more RNDs (77.8 vs. 9.3 %, p < 0.001), and better 5-year recurrence-free survival after the first RND (80.0 vs. 60.1 %, p = 0.049) than those with postablation sTg levels of >2 ng/mL. Overall BCR gradually decreased after each subsequent RND. Postablation sTg significantly correlated with postreoperation sTg (ρ = 0.509, p < 0.001). After adjusting for the number of metastatic lymph nodes excised at first RND and presence of extranodal extension, postablation sTg of ≤ 0.2 ng/mL was the only independent factor for BCR after one or more RNDs (odds ratio 37.0, 95 % confidence interval 5.68–250.0, p = 0.001).

Conclusions

Only a third of patients who underwent one or more RNDs for persistent/recurrent PTC had BCR afterward. Postablation sTg level was an independent factor for BCR. Completeness of the initial operation is important for the subsequent success of RND.