Salient haptic skills trainer: initial validation of a novel simulator for training force-based laparoscopic surgical skills

Background

There is an increasing need for efficient training simulators to teach advanced laparoscopic skills beyond those imparted by a box trainer. In particular, force-based or haptic skills must be addressed in simulators, especially because a large percentage of surgical errors are caused by the over-application of force. In this work, the efficacy of a novel, salient haptic skills simulator is tested as a training tool for force-based laparoscopic skills.

Methods

Thirty novices with no previous laparoscopic experience trained on the simulator using a pre-test–feedback–post-test experiment model. Ten participants were randomly assigned to each of the three salient haptic skills—grasping, probing, and sweeping—on the simulator. Performance was assessed by comparing force performance metrics before and after training on the simulator.

Results

Data analysis indicated that absolute error decreased significantly for all three salient skills after training. Participants also generally decreased applied forces after training, especially at lower force levels. Overall, standard deviations also decreased after training, suggesting that participants improved their variability of applied forces.

Conclusions

The novel, salient haptic skills simulator improved the precision and accuracy of participants when applying forces with the simulator. These results suggest that the simulator may be a viable tool for laparoscopic force skill training. However, further work must be undertaken to establish full validity. Nevertheless, this work presents important results toward addressing simulator-based force-skills training specifically and surgical skills training in general.     

Diagnostic laparoscopy: an update

Diagnostic laparoscopy has been in use since the last century. Advances in technology, coupled with increasing evidence of enhanced outcomes following its use, have renewed interest in this modality. Diagnostic laparoscopy guides surgeons in preventing unnecessary laparotomies in settings of acute abdomen, oncologists for accurate staging of malignancies from the esophagus to the colon, and hepatologists in the evaluation of acute as well as chronic liver diseases. Prospective clinical studies are awaited that will allow experimental technological advances, refining the methods of diagnostic laparoscopy, to be translated into more widespread use.     

Novel HIV-1 protease inhibitors (PIs) containing a bicyclic P2 functional moiety, tetrahydropyrano-tetrahydrofuran, that are potent against multi-PI-resistant HIV-1 variants

We identified GRL-1388 and -1398, potent nonpeptidic human immunodeficiency virus type 1 (HIV-1) protease inhibitors (PIs) containing a bicyclic P2 functional moiety, tetrahydropyrano-tetrahydrofuran (Tp-THF). GRL-1388 was as potent as darunavir (DRV) against various drug-resistant HIV-1 laboratory strains with 50% effective concentration (EC(50)s) of 2.6 to 32.6 nM. GRL-1398 was significantly more potent against such variants than DRV with EC(50)s of 0.1 to 5.7 nM. GRL-1388 and -1398 were also potent against multiple-PI-resistant clinical HIV-1 variants ((CL)HIV-1(MDR)) with EC(50)s ranging from 2.7 to 21.3 nM and from 0.3 to 4.8 nM, respectively. A highly DRV-resistant HIV-1 variant selected in vitro remained susceptible to GRL-1398 with the EC(50) of 21.9 nM, while the EC(50) of DRV was 214.1 nM. When HIV-1(NL4-3) was selected with GRL-1398, four amino acid substitutions--leucine to phenylalanine at a position 10 (L10F), A28S, L33F, and M46I--emerged, ultimately enabling the virus to replicate in the presence of >1.0 μM the compound beyond 57 weeks of selection. When a mixture of 10 different (CL)HIV-1(MDR) strains was selected, the emergence of resistant variants was more substantially delayed with GRL-1398 than with GRL-1388 and DRV. Modeling analyses revealed that GRL-1398 had greater overall hydrogen bonding and hydrophobic interactions than GRL-1388 and DRV and that GRL-1388 and -1398 had hydrogen bonding interactions with the main chain of the active-site amino acids (Asp29 and Asp30) of protease. The present findings warrant that GRL-1398 be further developed as a potential drug for treating individuals with HIV-1 infection.     

Subacute left ventricular rupture supported with a percutaneous left ventricular assist device

Cardiac rupture is a fatal complication of transmural myocardial infarction that is associated with high mortality. We describe the successful management of a case of subacute cardiac rupture and cardiogenic shock supported by a percutaneous left ventricular assist device (LVAD) as a bridge to surgery.     

Age Related Incidence and Early Outcomes of Hip Fractures: A Prospective Cohort Study of 1177 patients

Introduction  

Associated with the increase in the aging population, there is an increase in the incidence of hip fractures worldwide. Outcome following such fractures is affected by age of the patient. This study aims to assess the incidence and early outcome of hip fractures, comparing between different age groups.     

Conservative management of type 2 gallbladder perforation in a child

Gallbladder perforation(GBP) is a rare but serious complication of cholecystitis and needs to be managed promptly. Acalculus cholecystitis leading to GBP is frequently associated with enteric fever and found in critically ill patients, and a surgical approach is not always feasible in such patients. Use of percutaneous tube cholecystostomy(PTC) in such patients is a known entity but it is usually followed by interval cholecystectomy. Here we report a case of perforated gallbladder in a child managed conservatively and successfully with PTC as the definitive treatment wherein cholecystectomy was avoided. The functionality of the gallbladder was confirmed by a Tc99m-HIDA scan.