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The purpose of this paper is to propose a robotic system for percutaneous surgery. The key component in the system, a robotic arm that can manipulate a puncture needle is presented. The mechanical design, the motion control and the force control method of the robotic arm are discussed in the paper.

The arm with an arc mechanism placed on a 3D Cartesian stage is developed as a puncture needle manipulator to locate the position of the needle tip, tune the needle’s posture and actuate the puncture motion under the visual guidance of two orthogonal X-ray images of a patient by a surgeon. A focusing method by using two laser spots is proposed to automatically move the needle tip to a surgery entry point on the skin. A dynamics model is developed to control the position of the needle mechanism and an explicit force control strategy is utilized to perform the needle insertion.

With the surgical system, a surgeon can easily perform puncture operation by taking two orthogonal real-time X-ray images as a visual feedback and accurately navigating the needle insertion. The laser-guided focusing method is efficient in placement of the needle tip. The explicit force control strategy is proved to be effective for holding constant and stable puncture force in experiments.

The robotic arm has an advantage in easy redirection of the needle because the rotation and the translation are decoupled in the mechanism. By adopting simple laser pens and a well-developed kinematics model, the system can handle the entry point, locating task automatically. The focusing method and the force control method proposed in the paper are useful for the present system and could be intuitive for similar surgical robots.

Robotic coronary artery bypass (rCABG) is a relatively novel and less invasive form of surgery. A yearlong direct-to-consumer advertising (DTCA) campaign was initiated to provide the community with information regarding rCABG, increase awareness and recruit patients. To optimize information content and ensure appropriate messaging for future campaigns, this study aims to analyze the campaign effectiveness and compared service quality perceptions and clinical outcomes, following surgery across DTCA-responder and control groups.

The institution initiated an rCABG program and one-year DTCA campaign. The authors prospectively documented all rCABG referrals prompted by these ads (DTCA-responder group) and concurrent referrals from medical providers (controls). Groups were compared according to baseline characteristics, perioperative outcomes, patient satisfaction (HCAHPS survey) and functional capacity at three weeks (Duke Activity Status Index). At six months, both groups were surveyed for patient satisfaction and unmet expectations.

There were 103 DTCA responders and 77 controls. The subset of responders that underwent rCABG (n = 54) had similar characteristics to controls, except they were younger, less likely to have lung disease or to be scheduled as an urgent case. Both groups had similar 30-day clinical outcomes, functional capacity recovery and overall satisfaction at three weeks. Follow-up interviews at six months and four years revealed that the DTCA group reported more unmet expectations regarding the “size of the skin incisions” and “recovery time” but no concern about “expertise of their surgeon”.

The DTCA campaign was effective at recruiting patients. The specific focus of the ads and narrow timeframe for decision-making about CABG lends confidence that the incremental cases seen during the campaign were prompted primarily by DTCA. However, differences in unmet expectations underscore the need to better understand the impact of message content on patients recruited via DTCA campaigns.

This is one of the first studies to provide real-world direct empirical evidence of patients’ clinical and attitudinal outcomes for DTCA campaigns. Furthermore, the findings contradict prevailing beliefs that DTCA is ineffective for prompting surgical referrals.

Procedures can be categorized as certain surgeries based on their necessity and outcomes while others are classified as uncertain surgeries based on these areas. To account for this variance, policies such as the Affordable Care Act (ACA) call for health care providers to engage in shared decision making (SDM) with patients to ensure they are informed of treatment options and asked their preferences. Yet, gender may influence the decision-making process. Thus, this project examines the decision process and how gender impacts patients’ participation in decisions to undergo certain surgeries compared to uncertain surgeries.

This research project analyzed data from the National Survey of Medical Decisions 2006–2007 which surveyed the medical decisions of US residents 40 and older.

First, the data reveals that women felt more informed having uncertain surgeries compared to men. Second, patients were less likely asked their preference for surgery when undergoing certain surgeries compared to uncertain surgeries. Third, compared to men, women having uncertain surgeries were less likely to make the final decision to have surgery, compared to sharing the final decision with health care providers.

Due to the sample size, this project could not perform three-way interactions between gender, race, and surgery type.

Gender influences the level patients feel informed having uncertain surgeries. Though policy calls for SDM, health care providers are less likely to ask patients their preference for surgery regarding certain surgeries, relative to uncertain surgeries. Gender impacts the final decision-making process regarding whether patients should have uncertain surgeries.

Bundled payments for care are an efficient mechanism to align payer, provider, and patient incentives in the provision of health care services for an episode of care. In this chapter, we use agency theory to examine the evolution of bundled payment programs in private and public payer arrangements, and postulate future directions for bundled payment development as a key component in the provision and payment of health care services.

Four Washington State associations came together to form a novel organization in response to rising healthcare sector costs, coupled with the need to ensure efficient provision of high quality care that improves health outcomes. This article seeks to explain the work and progress of that organization.

The article takes the form of a historical narrative.

The initiative has evolved from reliance on grants to becoming self‐funding, expanded the scope of its activities, and satisfied the needs of the stakeholders.

This organizational model is more efficient than going it alone on every effort, and may be a desirable solution for other communities.

This is the first published description of a unique, non‐profit organization founded in 1998, which can serve as a model for other regions that wish to promote collaborative benchmarking among competitive independent health care providers.

The paper's purpose is twofold: to provide a predictive model for estimating in‐hospital mortality rates after coronary artery bypass grafting (CABG) in Spanish autonomous regions (AR) after adjusting relevant factors; and to determine whether there is a difference between expected and observed mortality rates.

All patients registered in a minimum basic data set (MSBD) undergoing CABG between 2000 and 2004 were selected. After bivariate analysis to explore associations between in‐hospital death and other variables, a multivariate analysis using logistic regression was conducted. The predictive model was evaluated using calibration and discrimination techniques. Standardized mortality ratios by AR were calculated.

The expected Spanish in‐hospital mortality rate after CABG was 7.68 and the observed rate was 7.69 deaths per 100 operations. Discrimination obtained with the model resulted in an area under the curve of 0.70 (95 per cent CI, 0.69‐0.71). When each AR's mortality rate is calculated and compared with the observed rate, some ARs present an observed mortality rate higher or lower than the expected rate according to adjusted variables in the model.

The MSBD registry does not contain patients' critical data, such as arterial damage severity, or in which hospital procedures were performed.

There are factors related to individual patient variation, financial resources or healthcare quality in different ARs, which should be investigated in follow‐up studies.

The paper shows that, although the global expected mortality rate is almost the same as the observed Spanish mortality rate, this similarity disappears when AR rates are compared.

Many foods naturally contain dietary Cr, but lost during processing and cooking. Type 2 diabetes mellitus (T2DM) has been associated with poor glycemic control and low Cr status. The objectives of the current study were to evaluate the dietary Cr intake and its relationship with diabetes risk factors in moderately obese subjects with T2DM.

Thirty‐six subjects (age: 26–65 years) were recruited through local advertisements. Subjects were taking stable doses of oral antidiabetic medication(s) excluding concomitant insulin. Subjects had HbA1c ≥7 per cent, persistent impaired glucose control (2 hour glucose >200 mg dL⁻¹) and at least a one‐year history of T2DM. Demographic characteristics, blood pressure, body mass index (BMI), family and medical history were recorded. Three‐day dietary intakes were collected and evaluated for Cr and nutrient content using Nutritionist V software. Plasma glucose, circulating insulin and lipid profile were analyzed. Homeostatic model assessment insulin resistance (IR), beta cell function (BCF) and derived ratios were calculated. Morning void urinary chromium levels were also measured.

It was observed that mean dietary Cr intake of adults (30 mcg) was below the suggested recommended daily intake (RDI) of 120 mcg day⁻¹. These estimates correspond to approximately 16.4 μg Cr per 1000 Kcals. A significant correlation was observed between dietary Cr and fasting insulin (p<0.05), total‐C (p<0.05), LDL‐C (p<0.01), triglycerides (p<0.05), BCF (p<0.05), TG/HDL‐C ratio (p<0.01), HOMA BCF (p<0.05) and with atherogenic index in plasma (p<0.05).

In this study, the consumption of chromium is less than the RDI. Overall the results suggest that the US diets are inadequate in the essential metal chromium. Further studies are required to explore the relationship of Cr absorption with dietary Cr intake and risk factors in T2DM.

The coupling impact of hybrid uncertain errors on the machine precision is complex, as a result of which the designing method with multiple independent error sources under uncertainties remains a challenge. For the purpose of precision improvement, this paper focuses on the robot design and aims to present an assembly precision design method based on uncertain hybrid tolerance allocation (UHTA), to improve the positioning precision of the mechanized robot, as well as realize high precision positioning within the workspace.

The fundamentals of the parallel mechanism are introduced first to implement concept design of a 3-R(4S) &3-SS parallel robot. The kinematic modeling of the robot is carried out, and the performance indexes of the robot are calculated via Jacobian matrix, on the basis of which, the 3D spatial overall workspace can be quantified and visualized, under the constraints of limited rod, to avoid the singular position. The error of the robot is described, and a probabilistic error model is hereby developed to classify the hybrid error sensitivity of each independent uncertain error source by Monte Carlo stochastic method. Most innovatively, a methodology called UHTA is proposed to optimize the robot precision, and the tolerance allocation approach is conducted to reduce the overall error amplitude and improve the robotized positioning precision, on the premise of not increasing assembly cost.

The proposed approach is validated by digital simulation of medical puncture robot. The experiment highlights the mathematical findings that the horizontal plane positioning error of the parallel robotic mechanism can be effectively reduced after using UHTA, and the average precision can be improved by up to 39.54%.

The originality lies in UHTA-based precision design method for parallel robots. The proposed method has widely expanding application scenarios in industrial robots, biomedical robots and other assembly automation fields.

This paper aims to summarize the radiological interventions that can be used by obstetricians and gynecologists.

E-health systems apply in all hospital sectors in the world; interventional radiology (IR) now includes transcatheter and percutaneous techniques that can be applied to various organ systems, including the female reproductive system and pelvis. Interventional radiologists can now offer many services to obstetricians and gynecologists. With the advent of new procedures and refinement of existing techniques, there are now a number of procedures that can be used to treat both vascular and non-vascular diseases. This review summarizes the radiological interventions that can be used by obstetricians and gynecologists.

This review is intended to help gynecologists and obstetricians understand the role of IR in their specialty. Many valuable vascular and nonvascular interventional services can be provided by radiologists for both obstetric and gynecological indications. Many of these IR procedures are minimally invasive with less risk to the patients.

IR is now being used to treat some conditions encountered in obstetrics and gynecology, in particular, uterine leiomyomas, placenta accreta, postpartum hemorrhage and pelvic congestion syndrome. Moreover, with the help of IR, radiologists can also manage several nonvascular pathologies, including drainage of pelvic abscesses, fallopian tube recanalization, image-guided biopsy and fluid collections involving ovarian lesions. The major challenges faced when performing obstetric IR procedures are reduction of radiation exposure for the patient and fetus and preservation of fertility. This review highlights the role of IR in the treatment of various vascular and nonvascular pathologies encountered in obstetrics and gynecology.