Impact of trainee involvement with robotic-assisted radical prostatectomy

Robotic-assisted surgery has been rapidly adopted within urology practice. As a result, academic centers are challenged with the burden of how to effectively train residents and fellows to perform robotic-assisted surgery without compromising outcomes. We evaluated the perioperative outcomes of trainee involvement with robotic-assisted radical prostatectomy (RARP) within our healthcare organization. We retrospectively reviewed RARP cases performed at our institution between September 2008 and December 2010 using a single da Vinci robotic platform. Trainees consisted of urology residents and fellows who operated with staff surgeons on select operating days, whereas two staff surgeon teams performed RARP on alternate days. We compared clinicopathologic variables including operating time, estimated blood loss, surgical margin rates, and complication rates between the trainee and staff-only surgeon groups. Overall, 1,019 RARP surgeries were performed within the study period and trainees participated in 162 cases (16 %). Clinical characteristics were similar between men undergoing surgery with a trainee and those without. Positive surgical margin rates were lower for patients with pT2 disease for cases with trainee involvement (11 vs. 19 %, p = 0.02), although overall margin rates and margin rates for patients with pT3 disease were similar between the groups (p = 0.34). Surgical cases involving trainees were longer (241 vs. 200 min, p < 0.001) and resulted in higher estimated blood loss (190 vs. 120 mL, p < 0.001) than the two staff surgeon cases. However, transfusion rates as well as intraoperative and postoperative complication rates did not differ significantly between groups. In conclusion, surgical margin rates were lower in teaching cases for patients with pT2 disease. Importantly, trainee involvement in RARP is safe, with similar perioperative outcomes to staff-only surgical cases. This information may be useful for training and surgical planning.     

Acoustic analysis of voice in dysarthria following stroke

Although perceptual studies indicate the likelihood of voice disorders in persons with stroke, there have been few objective instrumental studies of voice dysfunction in dysarthria following stroke. This study reports automatic analysis of sustained vowel phonation for 61 speakers with stroke. The results show: (1) men with stroke and healthy elderly men exhibited an identical voice profile, and men with stroke had only one significantly larger noise parameter (SPI—soft phonation index) than young healthy men; and (2) women with stroke and healthy elderly women exhibited an identical voice profile, except that women with stroke exhibited a significantly higher SPI than healthy elderly women. Although there were no significant differences in smoothed pitch perturbation quotient (sPPQ) and SPI between healthy elderly women and healthy young women, women with stroke exhibited significantly larger sPPQ and SPI than healthy young women. It is suggested that studies on sub‐groups of the stroke population that use a combination of perceptual and acoustic analyses will better illuminate the voice dysfunction in dysarthria following stroke.     

Multipoint dilution hemofiltration: A new technology for maximum convective clearance

Convection-based renal replacement therapies (RRTs) have the potential to improve patient outcomes when compared to diffusion-based RRT such as hemodialysis (HD), but have limited clearance rates. We propose and characterize multipoint dilution hemofiltration (MPD-HF), a purely convective blood purification technology which removes the fundamental filtration limit associated with convective RRT resulting in clearance rates on par with HD. In MPD-HF, filtration of liquid and solutes occurs along the length of the hollow fibers that convey the blood, and substitution fluid is pushed into the fibers at multiple points along their length. Since multiple filtration and dilution steps are contained within one pass of the blood through the hollow fiber, the fraction of fluid that can be filtered may be increased to allow a high clearance rate that removes a wide range of toxins. In vitro tests yielded an average steady-state filtrate fraction of 68%, exceeding commercial HDF cartridge filtrate fractions by a factor of approximately 3. The molecular weights of molecules cleared spans up to the cutoff of 66 kDa for albumin.     

Not small adults: the emerging role of pediatric pain services

Purpose

This review article explores the need for specialized pain care for children and adolescents and provides some historical context for our current knowledge base and clinical practice.

Principal findings

Pediatric patients have specialized needs with respect to assessment and management of pain. Acute pain care is modified by developmental considerations in both these areas; chronic pain encompasses a wide range of complex developmental, social, and psychological factors requiring the skills of different health disciplines to provide the best care.

Conclusions

Awareness of children’s pain has increased dramatically over the past three decades, and Canadians have performed a leadership role in much of the research. Specific multidisciplinary teams are a more recent phenomenon, but they are shown to be more effective and probably more cost effective than traditional treatment models. Important gaps in availability of resources to manage these patients remain.     

Meta-analysis of retrojugular versus antejugular approach for carotid endarterectomy

Introduction

The retrojugular approach for carotid endarterectomy (CEA) has been reported to have the advantages of shorter operative time and ease of dissection, especially in high carotid lesions. Controversial opinion exists with regard to its safety and benefits over the conventional antejugular approach.

Methods

A systematic review of electronic information sources was conducted to identify studies comparing outcomes of CEA performed with the retrojugular and antejugular approach. Synthesis of summary statistics was undertaken and fixed or random effects models were applied to combine outcome data.

Findings

A total of 6 studies reporting on a total of 740 CEAs (retrojugular approach: 333 patients; antejugular approach: 407 patients) entered our meta-analysis models. The retrojugular approach was found to be associated with a higher incidence of laryngeal nerve damage (odds ratio [OR]: 3.21, 95% confidence interval [CI]: 1.46–7.07). No significant differences in the incidence of hypoglossal or accessory nerve damage were identified between the retrojugular and antejugular approach groups (OR: 1.09 and 11.51, 95% CI: 0.31–3.80 and 0.59–225.43). Cranial nerve damage persisting during the follow-up period was similar between the groups (OR: 2.96, 95% CI: 0.79–11.13). Perioperative stroke and mortality rates did not differ in patients treated with the retrojugular or antejugular approach (OR: 1.26 and 1.28, 95% CI: 0.31–5.21 and 0.25–6.50).

Conclusions

Currently, there is no conclusive evidence to favour one approach over the other. Proof from a well designed randomised trial would help determine the role and benefits of the retrojugular approach in CEA.     

Fibronectin binding to thrombin-stimulated platelets: evidence for fibrin(ogen) independent and dependent pathways

Plasma fibronectin binds in a specific and saturable manner to thrombin- stimulated platelets. gamma-Thrombin stimulated 80% as much fibronectin binding to platelets as alpha-thrombin with conversion of less than or equal to 1% of platelet fibrinogen to fibrin. Afibrinogenemic and normal platelets bound similar quantities of fibronectin in the presence of calcium or magnesium-ethylene glycol tetra-acetic acid (EGTA). These observations indicate that fibronectin can interact with platelets without involvement of fibrin or fibrinogen. Nevertheless, two different effects of fibrin(ogen) on fibronectin binding were observed. First, exogenous fibrinogen inhibited fibronectin binding to thrombin-stimulated platelets. This inhibition was unidirectional, as fibronectin did not inhibit fibrinogen binding to ADP or thrombin- stimulated cells. Second, formaldehyde-fixed cells with surface- associated fibrin bound significant quantities of fibronectin. This interaction required calcium and did not occur on fixed cells with or without surface-bound fibrinogen. A portion of the ligand bound to fixed cells with surface-associated fibrin was modified to form a derivative with a molecular weight identical to that of the fibronectin subunit cross-linked to the alpha-chain of fibrin. This high mol wt derivative was also observed to a variable extent with living cells in the presence of magnesium or calcium but not in the presence of magnesium-EGTA. Thus, fibronectin binds to platelets by at least two mechanisms: (1) a fibrin(ogen)-independent pathway that requires divalent ions and is inhibited by exogenous fibrinogen; and (2) a fibrin-dependent pathway with an absolute calcium requirement. With nonaggregated, thrombin-stimulated platelets, the former pathway appears to predominate.