Reactive scheduling model for the operating theatre

This paper addresses the disruption management and rescheduling problem of the day-to-day running of a day surgery unit. The problem is modelled as a single machine scheduling problem with sequence dependent processing times and due dates. The proposed optimisation model sequences both elective and non-elective patients in the online environment. The weighted number of expected surgeries to complete on-time is maximised. We propose a branch and bound algorithm to solve the problem. Computational experiments are conducted illustrating its applicability to the problem of reactive scheduling in the operating theatre.     

A study of nurse scheduling in Japan

Scheduling nurses to staff shifts is a major problem in hospitals. The necessity of maintaining a certain level of service and skill in the makeup of every shift, while balancing the workload among the nurses involved, is incredibly difficult. It is often impossible to develop a schedule which satisfies all the requirements despite the time and resources spent in the effort. This paper summarizes all our published research on nurse scheduling to date. The difficulties realized by our two investigations in Japan are shown first, together with a resulting scheduling problem. The nurse scheduling model based on the results is then described. In this model, all constraints are divided into two essentially different types; that which maintains a certain level of skill for each shift ('shift constraints') and that which concerns the workload for each nurse ('nurse constraints'). By classifying the constraints in this manner, we can determine what is affected by a specific constraint when the constraint is not satisfied. We developed efficient algorithms while taking advantage of the structure of this model. Finally, it is shown that our algorithm can solve this problem for a 2-shift system efficiently.     

三层动态手术计划模型的构建

在静态的长期手术计划中,由于存在很多不确定性因素影响,使其很困难在实际中应用。文章提出一种动态三层手术计划排程,最上层为滚动资源分配模型,用线性规划模型为各科室合理分配手术室资源;中层采用多目标线性规划模型制定动态主手术计划;底层为在线调整模型,当意外情况出现时对动态手术计划进行调整。并结合某大型综合医院实情提供了数值算例,算例结果证明了模型的有效性。     

Evalution of Home Nurse Attachment in Bristol

By the end of June 1969 home nurses in Bristol were attached to 18 general practices caring for about 137,000 patients, or about one-third of the city''s population. Attachment was associated with an increase by about one-third in the number of patients referred by general practitioners for home nursing. Additional benefits derived from attachment during the nine months from January to September 1969 were 2,047 items of service performed by nurses in general practitioners'' surgeries, 65 home visits to patients who were not receiving domiciliary nursing care, improved communications between general practitioners and nurses, and opportunities for both doctors and nurses to widen their fields of work. The travelling expenses paid to Bristol''s nurses increased by 9·5%.It is suggested that the benefits to patients, doctors, and nurses of attachment far outweigh the costs and that there is scope for extending the role of the attached nurse in the surgery and in home visiting.     

Use and Utility of Hemostatic Screening in Adults Undergoing Elective,Non-Cardiac Surgery

Introduction

One view of value in medicine is outcome relative to cost of care provided. With respect to operative care, increased attention has been placed on evaluation and optimization of patients prior to undergoing an elective surgery. We examined more than 2 million patients having elective, non-cardiac surgery to assess the incidence and utility of pre-operative hemostatic screening, compared with a composite of history variables that may indicate a propensity for bleeding, to assess several important outcomes of surgery.

Materials & Methods

We queried the NSQIP database to identify 2,020,533 patients and compared hemostatic tests (PT, aPTT, platelet count) and history covariables indicative of potential for abnormal hemostasis. We compared outcomes across predictor values; used Person’s chi-square tests to compare differences, and logistic regression to model outcomes.

Results

Approximately 36% of patients had all three tests pre-operatively while 16% had none of them; 11.2% had a history predictive of potential abnormal bleeding. Outcomes of interest across the cohort included death in 0.7%, unplanned return to the operating room or re-admission within 30 days in 3.8% and 6.2% of patients; 5.3% received a transfusion during or after surgery. Sub-analyses in each of the nine surgical specialties’ most common procedures yielded similar results.

Conclusion

The limited predictive value of each hemostatic screening test, as well as excess costs associated with them, across a broad spectrum of elective surgeries, suggests that limiting pre-operative testing to a more select group of patients may be reasonable, equally efficacious, efficient, and cost-effective.     

The impact of inherited thrombophilia on surgery: A factor to consider before transplantation?

This article mainly reviews hypercoagulability—and specifically inherited thrombophilia—in different types of surgery including kidney transplantation, simultaneous kidney and pancreas transplantation, orthopedic surgery, vascular surgery, cardiac surgery and other categories of surgical procedures, with a major focus on its associated complications and the need to screen or not. A search was conducted using Medline and cross-referencing for articles related to thrombophilia, screening for it, and its association with surgical complications post-op. Thrombosis associated predisposing entities like factor V Leiden, Prothrombin and Methylene tetrahydrofolate reductase gene mutations, in addition to Protein C and S deficiencies, are discussed. In addition, common and relatively uncommon complications of thrombophilia in the above mentioned surgeries will be covered in length, as well as the necessity to screen for thrombophilia prior to the surgical step. This topic is gaining more and more importance for both surgeons and internists (especially Hematologists) and we, herein, present a general review of the published literature as an update on the subject.     

Pre-operative respiratory evaluation and management of patients for upper abdominal surgery.

Patients presenting for surgery, be it on an elective or emergency basis, do so in the hope that the anesthetic will be without risk. Yet complications which arise are not always due to anesthesia. More often, the surgical process and factors intrinsic to the patient are major determinants of outcome. Pre-operative assessment allows review of the patient and the proposed surgery, and formation of a plan of management for the pre-, intra-, and post-operative anesthetic care. This paper provides an overview of the pre-operative assessment and management of patients who are to undergo upper abdominal surgery, with the aim of minimizing their risk of post-operative pulmonary complications. In particular, factors which contribute to the development of post-operative respiratory problems are described.     

Satiation differentially affects performance in a learning assay by nurse and forager honey bees

When not satiated prior to training, there were no differences between foragers and nurse honey bees in the acquisition of an appetitively based conditioned response in an olfactory associative learning assay, but when satiated foragers showed faster acquisition than did nurses. Satiation-related differences between foragers and nurses were more a function of behavioral state than age, because satiated precocious foragers also showed faster acquisition rates than did satiated nurse bees, despite their similar ages. Tests of sucrose responsiveness and retention of conditioned responses indicate that the observed performance differences between nurses and foragers were more likely due to differential sensitivity of sensory and motor processes related to satiation rather than differences in cognitive ability.     

Current Trainee and Workforce Patterns for Thyroid and Parathyroid Surgery in the United States

ObjectiveThyroid and parathyroid surgery is performed by both general surgeons and otolaryngologists. We describe the proportion of surgeries performed by specialty, providing data to support decisions about when and to whom to direct research, education, and quality improvement interventions.MethodsWe tabulated case numbers for privately insured patients undergoing thyroid and parathyroid surgery in Marketscan: 2010–2016 and trainee case logs for residents and fellows in general surgery and otolaryngology. Summary statistics and tests for trends and differences were calculated.ResultsMarketscan data captured 114 500 thyroid surgeries. The proportion performed by each specialty was not significantly different. Otolaryngologists performed 58 098 and general surgeons performed 56 402. Otolaryngologists more commonly performed hemithyroidectomy (n = 25 148, 43.29% of all thyroid surgeries performed by otolaryngologists) compared to general surgeons (n = 20 353, 36.09% of all thyroid surgeries performed by general surgeons). Marketscan data captured 21 062 parathyroid surgeries: 6582 (31.25%) were performed by otolaryngologists, and 14 480 (68.75%) were performed by general surgeons. The case numbers of otolaryngology and general surgery trainees completing residency and fellowship varied 6- to 9-fold across different sites. The wide variation may reflect both the level of exposure a particular training program offers and trainee level of interest.ConclusionThyroid surgical care is equally provided by general surgeons and otolaryngologists. Both specialties contribute significantly to parathyroid surgical care. Both specialties should provide input into and be targets of research, quality, and education interventions.     

Operating room scheduling and rescheduling: a rolling horizon approach

In this work we consider the problem of selecting a set of patients among a given waiting list of elective patients and assigning them to a set of available operating room blocks. We assume a block scheduling strategy in which the number and the length of available blocks are given. As each block is related to a specific day, by assigning a patient to a block his/her surgery date is fixed, as well. Each patient is characterized by a recommended maximum waiting time and an uncertain surgery duration. In practical applications, new patients enter the waiting list continuously. Patient selection and assignment is performed by surgery departments on a short-term, usually a week, regular base. We propose a so-called rolling horizon approach for the patient selection and assignment. At each iteration short-term patient assignment is decided. However, in a look-ahead perspective, a longer planning horizon is considered when looking for the patient selection. The mid-term assignment over the next \(n\) weeks is generated by solving an ILP problem, minimizing a penalty function based on total waiting time and tardiness of patients. The approach is iteratively applied by shifting ahead the mid-term planning horizon. When applying the first week solution, unpredictable extensions of surgeries may disrupt the schedule. Such disruptions are recovered in the next iteration: the mid-term solution is rescheduled limiting the number of variations from the previously computed plan. Besides, the approach allows to deal with new patient arrivals. To keep limited the number of disruptions due to uncertain surgery duration, we propose also a robust formulation of the ILP problem. The deterministic and the robust formulation based frameworks are compared over a set of instances, including different stochastic realization of surgery times.     

手术室护士对外科手消毒相关知识的认知状况调查分析

目的:了解手术室护士对外科手消毒相关知识的认知状况,为手术室管理者提供护士掌握外科手消毒知识的整体水平,以全面提高外科手消毒的效果。方法:自行设计的问卷对哈尔滨市8家三级甲等综合性医院手术室护士进外科手消毒相关知识的认知调查。结果:目前手术室护士掌握外科手消毒相关知识的状况不容乐观,共20个被调查问题,回答正确率平均为49.85%;工作年限、第一学历、职称、学习过《医务人员手卫生规范》、消毒重要性的认识对答题结果的影响具有统计学意义(P0.05),表现为工作年限时间越长、第一学历越低、职称越高、学习过《医务人员手卫生规范》的、认为外科手术消毒重要的护士理论知识掌握情况越好。结论:被调查者自主学习较差,手术室管理者应当注重和加强手术室护士的外科手消毒专题学习培训与考核,理论与实践相结合,不断探索长期、可持续的培训教育模式,管理者制定与临床工作相结合并且适合不同学历背景和年资护士的培训方式和学习计划。充分调动护士的自我管理意识,建立外科手消毒"品管圈",分析和解决问题,使手术室的护理质量在持续的改进中得到不断提高。     

Design of Surgery Premises and Employment of Nurses

The surgery premises of many general practitioners have no accommodation for a nurse. Some have only a nurse/treatment room away from the consulting and examination rooms. Modern designs are no better, and are inadequate in view of the present trend to employ more nurses in group practices. Much of the value of a nurse is lost if she cannot help patient and doctor at the time of examination. The premises described here were designed to enable her to do so by combining the treatment room with a clinical room and a set of examination rooms.     

Planning elective operations on patients who smoke: survey of North American plastic surgeons.

Patient smoking status affects many aspects of plastic surgery, including patient selection, counseling, management, and outcomes. No specific recommendations for performing elective procedures on patients who smoke are available. The goal of this study was to determine the current practice standards and attitudes toward this often controversial topic. In September of 2000, 1600 members of the American Society for Aesthetic Plastic Surgery were sent questionnaires, 955 of which were returned. Questions elicited categorical answers, either dichotomous or multiple choice. Data were evaluated using logistic regression and the chi-square and binomial tests. Our results show that 60 percent (p < 0.01) of plastic surgeons routinely perform a less than optimal procedure on their patients who smoke. The survey measured willingness to perform various operative procedures on patients who smoke and types of smoking cessation aids offered. Of those physicians who require patients to quit smoking before surgery, only 16.7 percent (p < 0.01) would perform a nicotine test if they suspected noncompliance. Interestingly, 28.6 percent (p < 0.01) of the physicians responding admit to a smoking history, whereas only 1.5 percent (p < 0.01) continue to smoke, compared with the national smoking rate of almost 25 percent. Physicians who are previous smokers are less likely to offer smoking cessation aids than those who have never smoked, and the proportion not offering aids increases as the amount of previous smoking increases (p = 0.02). This study shows that a wide range of opinions exists on which elective surgical procedures should be performed on patients who smoke. Furthermore, the physician's prior smoking history influences this decision. No clear consensus exists on how best to treat patients who smoke who request elective surgeries. Although surgeons would prefer to operate on nonsmokers, they are faced with a significant population of patients who use tobacco. No clear consensus exists on how best to treat these individuals. Advancements in wound healing research and smoking cessation aids will provide more insight into this treatment dilemma.     

Early Identification of Individuals with Poorly Controlled Diabetes Undergoing Elective Surgery: Improving A1c Testing in the Preoperative Period

ObjectiveTo describe a process improvement strategy that increased the identification of individuals with poorly controlled diabetes (glycated hemoglobin [A1C] ≥ 8%) undergoing elective surgery at a major academic medical center and increased their access to specialist care.MethodsAn algorithm was developed to ensure A1C measurements were obtained as per the American Association of Clinical Endocrinologists/American Diabetes Association (AACE/ADA) guidelines. The diabetes management team worked collaboratively with anesthesiologists, surgeons, and preoperative nurse practitioners to improve the glycemic control of patients with an A1C ≥ 8%.ResultsBefore implementing the program, A1C testing was recorded in 854 out of 2,335 (37%) patients with diabetes seen in the preoperative clinic from January 1, 2011 to December 31, 2012. The program was instituted in February 2013. From February 2013 to February 2014, A1C testing occurred in 1,236 out of 1,334 (93%) patients with diabetes. After excluding those scheduled for same day surgery, 228 patients were considered high risk with A1C ≥ 8%, and 175 were available for endocrine preoperative consultation. The program led to significant blood glucose level improvements on the day of surgery.ConclusionA process improvement strategy to evaluate and treat diabetes in the preoperative period of elective surgery patients was implemented by a multidisciplinary team (endocrinologists, nurse practitioners, anesthesiologists, and surgeons) and resulted in a substantial improvements in obtaining A1C tests, access to specialist diabetes care, and glycemic control on the day of surgery. The impact of improved glycemic control on hospital and surgical outcomes needs further evaluation. (Endocr Pract. 2015;21:231-236)     

The Surgical Site Infection Risk Score (SSIRS): A Model to Predict the Risk of Surgical Site Infections

Background

Surgical site infections (SSI) are an important cause of peri-surgical morbidity with risks that vary extensively between patients and surgeries. Quantifying SSI risk would help identify candidates most likely to benefit from interventions to decrease the risk of SSI.

Methods

We randomly divided all surgeries recorded in the National Surgical Quality Improvement Program from 2010 into a derivation and validation population. We used multivariate logistic regression to determine the independent association of patient and surgical covariates with the risk of any SSI (including superficial, deep, and organ space SSI) within 30 days of surgery. To capture factors particular to specific surgeries, we developed a surgical risk score specific to all surgeries having a common first 3 numbers of their CPT code.

Results

Derivation (n = 181 894) and validation (n = 181 146) patients were similar for all demographics, past medical history, and surgical factors. Overall SSI risk was 3.9%. The SSI Risk Score (SSIRS) found that risk increased with patient factors (smoking, increased body mass index), certain comorbidities (peripheral vascular disease, metastatic cancer, chronic steroid use, recent sepsis), and operative characteristics (surgical urgency; increased ASA class; longer operation duration; infected wounds; general anaesthesia; performance of more than one procedure; and CPT score). In the validation population, the SSIRS had good discrimination (c-statistic 0.800, 95% CI 0.795–0.805) and calibration.

Conclusion

SSIRS can be calculated using patient and surgery information to estimate individual risk of SSI for a broad range of surgery types.     

Two-layer passive/active anisotropic FSI models with fiber orientation: MRI-based patient-specific modeling of right ventricular response to pulmonary valve insertion surgery

A single-layer patient specific right/left ventricle patch (RV/LV/Patch) combination model with fluid-structure interactions (FSI) was introduced in our previous papers to evaluate and optimize human pulmonary valve replacement/insertion (PVR) surgical procedure and patch design. In this paper, an active anisotropic model with two-layer structure for ventricle wall and tissue fiber orientation was introduced to improve previous isotropic model for more accurate assessment of RV function and potential application in PVR surgery and patch design. A material-stiffening approach was used to model active heart contraction. The computational models were used to conduct "virtual (computational)" surgeries and test the hypothesis that a PVR surgical design with a smaller patch and more aggressive scar tissue trimming would lead to improved RV cardiac function recovery. Results from our models validated by pre-operation data indicated that the small patch design had 11% improvement in RV function as measured by RV ejection fraction, compared to the conventional patch. Maximum Stress-P1 value from the active anisotropic model was 121.2% higher than that from the passive isotropic model. Computational RV volume predictions agreed well with CMR-measured volume data (error < 2%).     

Nurse practitioners in primary care iv. Impact of an interdisciplinary team on attitudes of a rural population.

Attitudes toward the expanded role of nurse practitioners in primary care (family practice nurses) have been determined for persons from a semirural area who chose as their principal souce of care an interdisciplinary family medical centre (FMC) incorporating two nurse practitioners, and those for whom the FMC was not the usual source of care. Data were obtaine using"before-and-after" structured interviews of a random sample of persons living in a southern Ontario township. Slowly evolving, nonsignificant trends of greater acceptance were observed among patiens who had dealth with family practice nurses. The greatest change observed was an increased acceptance of the nnurse by FMC users as the person who would be contacted as a second choice if theirfirst choice, usually a physician, could not be reached in specific worrry-inducing situations. FMC users depended more on nurses to provide information. A conclusion of increased general acceptance of the family practive nurse by FMC users is supported by a 34 per cent higher use of nurses by FMC patients compared to other persons of comparable characteristics living in the same community.     

Nurse therapists in behavioural psychotherapy.

Five registered mental nurses (R.M.N.s) were trained over two years to become behavioural psychotherapists for adult neurotic disorders. They achieved results comparable to those obtained with similar patients and methods by psychologists and psychiatrists. Similar results were maintained when over a third year the therapists were seconded to work in four hospitals and a general practice. Patients were satisfied at being treated by nurses. After initial teething difficulties nurse therapists became valuable members of treatment teams during both training and secondment, becoming accepted by most nurses, psychologists, and psychiatrists with whom they came into contact. The training of further nurse therapists would facilitate treatment of many disabled neurotics who would otherwise go without effective treatment. Training nurse therapists takes less time and money than training psychologists and psychiatrists because less of their education is redundant to the skills involved. The pool of R.M.N.s suitable for training is much larger than that of psychiatrists and psychologists. The nurse therapists can be integrated relatively easily into treatment teams. The present nursing structure imposes restrictions on the advancement of clinical nurse specialists and a clinical tree is badly needed parallel with present administrative and teaching hierarchies. An 18-month course in adult behavioural psychotherapy has been recognized by the Joint Board of Clinical Nursing Studies for England and Wales so that nurse therapists seem destined to be a lasting feature of future treatment teams.     

Incidence and prognosis of patients with small intestinal neuroendocrine tumors in a population based nationwide study

Background & aimsSmall intestinal neuroendocrine tumours (SI-NETs) are the most frequent malignant tumours of the small intestine. Population based studies on SI-NETs are scarce. We aimed to examine the incidence, presentation of disease and prognosis of SI-NET and to determine patient prognosis in those undergoing emergency or elective surgery.MethodsThis was a retrospective population-based study. Information on all patients diagnosed with neuroendocrine tumours of the small intestine (excluding duodenum) from the beginning of the Icelandic Cancer Registry and the pathology departments in the country (1966–2017). Detailed phenotypic information was obtained from medical records on symptoms at diagnosis, treatment, recurrence and survival.ResultsA total of 113 patients with SI-NETs were identified, 3 patients were excluded due to lack of data and/or diagnostic error, leaving 110 patients for final analysis. The incidence of SI-NET was 0.78/100,000 and did not increase during the study period. A total of 42 % (n = 46) of patients were diagnosed incidentally. Long-term prognosis, after a landmark of 12 months, was better in patients who were diagnosed incidentally (HR 0.52; p = 0.03). Overall 89 % (n = 98) of cases underwent surgical resection of the primary tumor, 31 % (n = 30) patients acute or semi-acute surgery and 69 % (n = 68) elective surgery. Emergency surgery was associated with a 6-fold risk of death in the first 12 months after surgery (HR: 5.99; p = 0.01) and associated with more severe surgical complications. However, there was no difference in the long-term risk of death after the first 12 months (HR: 1.39; p = 0.27).ConclusionsThe incidence of SI-NETs has not changed significantly in the last decades. Incidentally diagnosed SI-NET was associated with a favorable long-term prognosis. Emergency surgery in patients with SI-NET was associated with a significantly worse short-term risk of mortality compared to those who underwent elective surgery.     

An integrated approach to patient-specific predictive modeling for single ventricle heart palliation

In patients with congenital heart disease and a single ventricle (SV), ventricular support of the circulation is inadequate, and staged palliative surgery (usually 3 stages) is needed for treatment. In the various palliative surgical stages individual differences in the circulation are important and patient-specific surgical planning is ideal. In this study, an integrated approach between clinicians and engineers has been developed, based on patient-specific multi-scale models, and is here applied to predict stage 2 surgical outcomes. This approach involves four distinct steps: (1) collection of pre-operative clinical data from a patient presenting for SV palliation, (2) construction of the pre-operative model, (3) creation of feasible virtual surgical options which couple a three-dimensional model of the surgical anatomy with a lumped parameter model (LPM) of the remainder of the circulation and (4) performance of post-operative simulations to aid clinical decision making. The pre-operative model is described, agreeing well with clinical flow tracings and mean pressures. Two surgical options (bi-directional Glenn and hemi-Fontan operations) are virtually performed and coupled to the pre-operative LPM, with the hemodynamics of both options reported. Results are validated against postoperative clinical data. Ultimately, this work represents the first patient-specific predictive modeling of stage 2 palliation using virtual surgery and closed-loop multi-scale modeling.