From transabdominal to totally extra-peritoneal robotic ventral hernia repair: observations and outcomes.

PURPOSE: While robotic-assisted hernia repair has increased the popularity of minimally invasive hernia surgery, selecting between the types of approaches is a challenge for both experts and novices alike. In this study, we compared a single surgeon's early experience transitioning from transabdominal hernia repair with sublay mesh in either the pre-peritoneal or retrorectus space (TA-SM) and enhanced-view totally extra-peritoneal (eTEP) ventral hernia repair in the peri-operative and long-term post-operative time periods. METHODS: We conducted a retrospective review of 50 eTEP and 108 TA-SM procedures to collect demographics, intraoperative details, and 30-day and 1-year post-operative outcomes. Statistical analysis was performed utilizing Chi-square analysis, Fisher's test, and two sample t-tests with equal variances. RESULTS: There were no significant differences in patient demographics or comorbidities. eTEP patients had larger defects (109.1 cm2 vs. 31.8 cm2, p = 0.043) and mesh used (432.8 cm2 vs. 137.9 cm2, p = 0.001). Operative times were equivalent (158.3 ± 90.6 min eTEP and 155.8 ± 65.2 min TA-SM, p = 0.84), but conversion to alternate procedure type was higher for the transabdominal approach (4% eTEP vs. 22% TA-SM, p < 0.05). Hospital stay was less in the eTEP cohort (1.3 days vs. 2.2 days, p < 0.05). Within 30 days, there were no significant differences in emergency visits or hospital readmissions. There was a greater propensity for eTEP patients to develop seromas (12.0% vs. 1.9%, p < 0.05). At 1 year, there was no statistically significant difference in recurrence rate (4.56% eTEP vs. 12.2% TA-SM, p = 0.28) respective to average time to recurrence (9.17 months eTEP vs. 11.05 months TA-SM). CONCLUSION: The eTEP approach can be adopted safely and efficiently, and may have superior peri-operative outcomes including fewer conversions and reduced hospital stay.

The role of context in persistent avoidance and the predictive value of relief.

Fear renewal occurs when the context changes after fear extinction; however, whether avoidance is also influenced by context changes following fear extinction is untested. Forty-two participants performed an avoidance task within a typical fear renewal procedure. During Pavlovian conditioning, two stimuli (CS+) were associated with an aversive electrical stimulus (US), while a third stimulus was not (CS-). During subsequent avoidance learning, clicking a button canceled the delivery of the US during one but not the other CS+. Fear-related levels were then reduced by removing the US and the button in a new context (fear extinction with response prevention [Ext-RP]). Next, persistence of avoidance was tested in the extinction context B (group ABB) or the original conditioning context A (group ABA). We also tested whether ratings of relief pleasantness (based on both the CS- and the avoided CS+) during avoidance and Ext-RP predicted individual levels of persistent avoidance. Results showed that persistent avoidance was higher in conditioning context A than in extinction context B, and was predicted by higher relief pleasantness during avoidance conditioning. We conclude that persistent avoidance poses a threat to the long-term success of Ext-RP, and we propose that interventions aimed at mitigating the influence of context and relief levels might prove beneficial in this regard.

Robotic ventral hernia repair: a safe and durable approach.

BACKGROUND: Short-term success following robotic-assisted ventral hernia repair (RVHR) is well established; however, data describing outcomes after the first year are limited. In this study, we followed a cohort of patients with an average of 1.8 years of follow-up to demonstrate the durability of this technique and examine risk factors for recurrence. METHODS: A retrospective analysis of RVHR performed by a single surgeon from 2012 to 2016 was done. The technical approach for hernia repair consisted of tension-free primary fascial closure with placement of preperitoneal mesh when possible. The primary end point of hernia recurrence was determined based on physical examination or imaging documented in the medical record. A logistic regression model was used to identify patient risk factors for recurrence. RESULTS: One hundred and eight RVHRs were performed over 4 years. Mean age was 52.72 ± 13.61 years, BMI was 33.07 ± 7.82 kg/m2, and hernia defect size was 70.1 ± 86.3 cm2. In terms of patient characteristics, 17.6% of patients were diabetic, 13.9% were smokers preoperatively, 72.2% were ASA class 3 or higher, and 29.6% had prior VHR. Primary fascial closure was achieved in all RVHRs, with 23.1% requiring component separation. Mesh was used in 97.2% of patients: 79.5% had preperitoneal mesh and 17.6% had intraperitoneal onlay mesh. Ninety-eight percent of patients had long-term follow-up at a mean of 625.6 days. Recurrence rate was 12%, with one recurrence attributed to an inguinal hernia fixed concurrently with a midline defect. There were no statistically significant differences in gender, age, BMI, ASA class, incidence of diabetes, smoking status, or number of previous hernia repairs. Hernia defect size and perioperative complications including SSO, ileus, obstruction, or any other medical complication were not predictive of recurrence. Technical approach did not affect outcomes. CONCLUSION: RVHR is safe and durable with a low recurrence rate at a mean of 21 months postoperatively. Patient characteristics or type of repair were not predictive of recurrence.

Probing the role of perception in fear generalization.

Behavior in novel situations is guided by similarities to previous experiences, a phenomenon known as generalization. Despite the widespread influence of generalization on healthy and pathological behavior, insight into the underlying mechanisms is lacking. It remains unclear whether a failure to notice situational changes contributes to the generalization of learned behavior. We combined a fear conditioning and generalization procedure with a perceptual decision task in humans and found that a failure to perceive a novel stimulus as different from the initial fear-evoking stimulus was associated with increased conditioned responding. These findings demonstrate the potential of a perception-centered approach to better understand (pathological) behavior and its underlying mechanism and are a promising avenue for the development of refined generalization protocols.

Biased pain reports through vicarious information: A computational approach to investigate the role of uncertainty.

Expectations about an impeding pain stimulus strongly shape its perception, yet the degree that uncertainty might affect perception is far less understood. To explore the influence of uncertainty on pain ratings, we performed a close replication of the study of Yoshida, Seymour, Koltzenburg, and Dolan (2013), who manipulated vicarious information about upcoming heat pain and found evidence for uncertainty-induced hyperalgesia. In our study, we presented eight fictitious ratings of previous participants prior the delivery of electrocutaneous pain. The vicarious information was either biased to over- or underreport pain levels based on the participant's psychometric function. We induced uncertainty by manipulating the variation of the vicarious information. As in Yoshida et al. (2013), four computational models were formulated, such that each model represented a different way of how the pain ratings might have been generated by the physical stimulus and the vicarious information. The four competing models were tested against the data of each participant separately. Using a formal model selection criterion, the best model was selected and interpreted. Contrary to the original study, the preferred model for the majority of participants suggested that pain ratings were biased towards the average vicarious information, ignoring the degree of uncertainty. Possible reasons for these diverging results are discussed.

Value of FNAC in diagnosis of different types of thyroiditis and its comparison with clinical and biochemical findings.

FNAC has developed tremendous improvement in the diagnosis of thyroiditis. The present study was designed to asses the usefulness of FNAC to diagnose various types of thyroiditis and to study their smear patterns. Over a period of one-year, 70 cases of thyroiditis have been evaluated on the basis of cytomorphological criteria and clinical findings of patients. The age ranged from 12-60 years. Majority of the cases were between 21 to 30 years of age with female preponderance in each group of thyroiditis. Among 70 cases, 26(37.14%) cases were Hashimoto's thyroiditis, 21(30%) cases were lymphocytic thyroiditis, seven (10%) cases as granulomatous thyroiditis and 16(22.8%) were non-specific thyroiditis. Further study was carried out in these 70 cases regarding biochemical thyroid status, ultrasonography and radionucleotide scan. Blood was drawn from all patients for estimation of antibody titer to compare with cytological diagnosis. It was found that, clinical examination and history of patients had limited value in the diagnosis of thyroiditis. Ultrasonography and thyroid scan could not reliably differentiate between patients with autoimmune thyroiditis and those with simple and nodular goiter. Biochemically hypothyroidism is more frequently evaluated with Hashimoto's diseases. On the other hand, hyperthyroidism was observed in most other types of thyroiditis. Cytologically diagnosed 78.72% cases of autoimmune thyroiditis had positive antibody titer. From the present study it is concluded that FNAC is a safe, reliable, cost effective and time saving method in the diagnosis of thyroiditis. Being a benign condition also reduce the rate of unnecessary operation, which can be treated conservatively.

Natriuretic peptides like NO facilitate cardiac vagal neurotransmission and bradycardia via a cGMP pathway.

We tested the hypothesis that natriuretic peptide receptors (NPRs) that are coupled to cGMP production act in a similar way to nitric oxide (NO) by enhancing acetylcholine release and vagal-induced bradycardia. The effects of enzyme inhibitors and channel blockers on the action of atrial natriuretic peptide (ANP), brain-derived natriuretic peptide (BNP), and C-type natriuretic peptide (CNP) were evaluated in isolated guinea pig atrial-right vagal nerve preparations. RT-PCR confirmed the presence NPR B and A receptor mRNA in guinea pig sinoatrial node tissue. BNP and CNP significantly (P < 0.05) enhanced the heart rate (HR) response to vagal nerve stimulation. CNP had no effect on the HR response to carbamylcholine and facilitated the release of [(3)H]acetylcholine during atrial field stimulation. The particulate guanylyl cyclase-coupled receptor antagonist HS-142-1, the phosphodiesterase 3 inhibitor milrinone, the protein kinase A inhibitor H89, and the N-type calcium channel blocker omega-conotoxin all blocked the effect of CNP on vagal-induced bradycardia. Like NO, BNP and CNP facilitate vagal neurotransmission and bradycardia. This may occur via a cGMP-PDE3-dependent pathway increasing cAMP-PKA-dependent phosphorylation of presynaptic N-type calcium channels.