Researcher:
Yavuz, Yunus

Profile Picture
ORCID

Job Title

Other

First Name

Yunus

Last Name

Yavuz

Name

Name Variants

Yavuz, Yunus

Email Address

Birth Date

Filters

2017 - 201912020 - 20223

Advanced Search

Filter by

Settings

Researcher Of Publications: search.filters.isAuthorOfPublication.d733bde3-f67f-4f41-b7f6-7aba598fd71d

Search Results

Now showing 1 - 4 of 4
  • Placeholder
    PublicationMetadata only
    Can postoperative pain be prevented in bariatric surgery? efficacy and usability of fascial plane blocks: a retrospective clinical study
    (Springer, 2022) Coşarcan, Sami Kaan; Doğan, Alper Tunga; Yavuz, Yunus; Erçelen, Ömür; Other; Faculty Member; School of Medicine; School of Medicine; N/A; 12305
    Background: Providing analgesia after bariatric surgery might be challenging due to a high prevalence of obstructive sleep apnea syndrome and the increased sensitivity to respiratory depression triggered by opioid overuse after surgery. Various combination methods with paracetamol, nonsteroidal anti-inflammatory drugs (NSAIDs), and other pain medications such as ketamine or gabapentin have been suggested for reduction of the opioid usage. Regional anesthetic techniques represent a valuable option as they improve patient comfort while reducing opioid-related side effects. In this study, we have evaluated the adjuvant benefits of these various techniques in reduction of the postoperative pain in bariatric surgery. Methods: After the approval of the IRB Ethics Committee, the records of the patients who had laparoscopic bariatric surgery between January 2019 and December 2021 were reviewed retrospectively. Results: Records of 120 patients who underwent laparoscopic bariatric surgery between January 2019 and December 2021 were reviewed. In total, 113 patients with full documentation were included in this study. Among these, 74 patients were administered regional analgesia. The main regional analgesia techniques were transversus abdominis plane and rectus sheath block. The pain scores of those receiving regional analgesia were statistically low. The opioid consumption after transversus abdominis plane and rectus sheath block was significantly lower than that of others. External oblique intercostal block alone provides a postoperative opioid consumption similar to those of transversus abdominis plane and rectus sheath block. Conclusion: The use of fascial plane blocks in bariatric surgery significantly reduces opioid consumption. Transversus abdominis plane and rectus sheath block combination and external oblique intercostal block seem to be the most effective options.
  • Placeholder
    PublicationMetadata only
    No change in reward responsiveness, but decreased functional connectivity with right nucleus accumbens and left lateral occipital- precuneus cortex 3 months after sleeve gastrectomy
    (Elsevier Science Inc, 2020) Eren, Candan Yasemin; Uymaz, Derya Salim; Yavuz, Yunus; Kılıç, Özge; Eser, Hale Yapıcı; PhD Student; Teaching Faculty; Other; Doctor; Faculty Member; Graduate School of Health Sciences; N/A; School of Medicine; N/A; School of Medicine; N/A; Koç University Hospital; N/A; Koç University Hospital; N/A; N/A; 175554; N/A; 167890; 134359
    Background: Obesity is known to be linked to nucleus accumbens activity and altered reward responsiveness. Sleeve gastrectomy (SG) is often used for treatment of morbid obesity and activity in the NAcc was shown to positively affect weight-loss at 12 months post-surgery. The aim of this study is to measure the change in reward responses and nucleus accumbens (NAcc) functional connectivity 3 months after SG. Methods: 25 patients with a diagnosis of obesity were evaluated pre-surgery and 3 months post-surgery with Snaith-Hamilton Pleasure Scale (SHAPS), Beck Depression Inventory (BDI) and body weight. As a laboratory-based measure of reward learning, they performed probabilistic reward task (PRT). Resting-state fMRI images were obtained from 7 participants pre and post surgery. Results: Both SHAPS, BDI and response bias and discriminability scores in PRT were not significantly different post-surgery. Mean percentage body weight loss of individuals were 20.07 %. Right NAcc functional connectivity with left lateral occipital- precuneus cortex decreased significantly post-surgery (105 voxels, voxel wise threshold p<0.05, FWE corrected), however no change in left NAcc connectivity was observed. Change in right NAcc functional connectivity was not correlated with weight loss. Conclusions: Previous literature on gambling and alcoholism showed increased NAcc-precuneus connectivity. Functional connectivity decrease between NAcc and precuneus in the resting state can be associated with reduced impulsivity and sensation-seeking observed after BS which correlates positively with successful weight loss.
  • Placeholder
    PublicationMetadata only
    Can we benefit from the preoperative psychometric test with symptom checklist-90-revised (SCL-90-R) to predict weight loss after sleeve gastrectomy?
    (Springer, 2022) Sobutay, Erman; Bilgiç, Çağrı; Şahin, Banu; Mercan, Sibel; Kabaoğlu, Burçak; Yavuz, Yunus; Uymaz, Derya Salim; Eser, Hale Yapıcı; Yavuz, Yunus; Teaching Faculty; Faculty Member; Other; School of Medicine; School of Medicine; School of Medicine; 175554; 134359; N/A
    Background: The psychological assessment is crucial before bariatric surgery. Derogatis’ Symptom Checklist-90-Revised (SCL-90-R) is one of the most widely used measures of psychological symptoms and distress in both clinical and research settings. We aimed to investigate the predictive value of SCL-90-R subscale scores on postoperative excess weight loss percentage (EWLP) after laparoscopic sleeve gastrectomy (LSG). Methods: Patients who underwent primary LSG for morbid obesity and fully completed preoperative SCL-90-R between January 2016 and July 2019 were retrospectively examined. A multiple linear regression analysis was performed to investigate the relationship between descriptive and psychological variables associated with EWLP percentage at the 12th-month. Results: One hundred six patients who met the inclusion criteria were analyzed. The adequate weight loss (EWLP ˃ 50%) was achieved in 90% of patients after 12 months. The multiple linear regression analysis indicated that younger patients (β =  − 0.695; 95% CI − 1.056, − 0.333; p < 0.001), and patients with preoperative lower BMI (β =  − 1.524; 95% CI − 1.974, − 1.075; p < 0.001) achieved higher EWLP at 12th-month. High somatization score (β = 11.975; 95% CI 3.653, 20.296; p = 0.005) and a low Global Severity Index (GSI) score (β =  − 24.276; 95% CI − 41.457, − 7.095; p = 0.006) had a positive effect on EWLP at 12th-month. Conclusions: Preoperative psychological testing can help predict surgical outcomes in the bariatric population. More intense lifestyle and behavioral support can be applied by targeting patients who are expected to lose less weight after surgery, and patients’ weight loss potential can be increased.
  • Placeholder
    PublicationMetadata only
    Serum leptin, obestatin, and ghrelin levels and gastric emptying rates of liquid and solid meals in non-obese rats with roux-en-y bypass surgery or prosthesis placement: implications for the role of vagal afferents
    (Springer, 2017) Kumral, Zarife Nigar Ozdemir; Memi, Gulsun; Cevik, Ozge Dagdeviren; Yegen, Cumhur; Yegen, Berrak C.; N/A; Yavuz, Yunus; Other; School of Medicine; N/A
    Background: The present study aimed to investigate the effects of Roux-en-Y gastric bypass (RYGB) and prosthesis placement on gastric emptying rate in conjunction with serum ghrelin-obestatin-leptin responses in non-obese rats with intact or denervated afferent innervation. Methods: Under anesthesia, male Sprague-Dawley rats underwent either sham operation, RYGB, prosthesis, and/or Gregory cannula placement. Three weeks later, liquid or solid gastric emptying tests were performed and serum ghrelin, leptin and obestatin levels were measured. Results: Both prosthesis placement and RYGB surgery delayed non-nutrient liquid emptying; while solid nutrient emptying was delayed only by RYGB. Nutrient-dependent (acid, hyperosmolal and peptone) delay in liquid emptying was abolished in rats with prosthesis. By vagal afferent denervation, delayed liquid emptying was abolished, while solid emptying was further delayed in rats with prosthesis. Ghrelin and obestatin levels were depressed in prosthesis-placed rats, but RYGB surgery had no impact on both levels. Leptin level was elevated in solid-food-given rats with prosthesis, but not changed in RYGB group, while it was reduced following liquid meal. All the changes observed in ghrelin, obestatin, or leptin levels in response to meal ingestion were reversed with vagal afferent denervation. Conclusions: Both RYGB and prosthesis placement had delaying effects on gastric emptying rate of non-obese rats. Our results indicate that the short-term changes in gastric motility and hormone responses induced by volume reduction are reversed by afferent denervation, suggesting that sparing the vagal innervation could be essential for reaching optimum motility and hormone changes expected after bariatric surgery.