Intestinal malrotation in the adult population: Diagnosis, management, and outcomes after laparoscopic Ladd procedure.

BACKGROUND: The Ladd procedure is the treatment of choice for patients with intestinal malrotation; however, the long-term outcomes of the laparoscopic Ladd procedure are not well documented. This study aimed to review the presentation, management, and outcomes of adult patients who underwent a laparoscopic Ladd procedure. METHODS: A retrospective review was conducted to identify adult patients with malrotation who underwent a laparoscopic Ladd procedure between January 1995 and June 2022 at the Mayo Clinic in Rochester, Minnesota. Patient details and follow-up data were obtained from the electronic medical records. Patients were invited to participate in a structured phone interview to assess symptoms and quality of life (QoL). RESULTS: A total of 44 patients underwent the laparoscopic Ladd procedure. Of the 44 patients, 42 (95.5 %) were symptomatic, with 7 (16.7 %) presenting with acute symptoms. Moreover, 8 laparoscopic procedures (13.6 %) required conversion to an open procedure. The median estimated blood loss was 20 mL (IQR, 10-50), operative time was 2.3 h (IQR, 1.8-2.8), and hospital length of stay was 2 days (IQR, 2-3). Postoperative ileus was the most common complication (18.0 %). The median follow-up was 8.00 years (IQR, 2.25-13.00), with more than 90.0 % of patients having partial or complete symptom resolution. Of note, 28 patients (63.6 %) completed phone interviews. Moreover, 1 patient (2.0 %) reported a postoperative volvulus. When asked to compare their current symptoms with those preoperatively, 78.6 % of patients noted that they were significantly better. Furthermore, 85.7 % of patients reported that their QoL was significantly better after surgery. Finally, 96.4 % of patients would recommend the procedure to a friend or family member with the same condition. CONCLUSION: The laparoscopic Ladd procedure is a safe and effective surgical procedure for adult patients with intestinal malrotation.

Robotic modified Sugarbaker technique for parastomal hernia repair: a standardized approach.

Parastomal hernia (PSH) is a prevalent long-term morbidity associated with stoma construction, and the optimal operative management remains uncertain. This study addresses the need for a standardized approach to symptomatic PSH repair, focusing on the robotic-assisted modified Sugarbaker technique with composite permanent mesh. The study, conducted in a high-volume colon and rectal surgery referral practice, outlines a systematic approach to patient selection, surgical procedures, and postoperative care. Preoperative evaluations include detailed medical and surgical histories, impact assessments of PSH, and oncological history reviews. The surgical technique involves the Da Vinci Xi™ robotic platform for adhesiolysis, hernia content reduction, stoma revision if needed, narrowing of the enlarged stoma trephine, lateralization of the stoma limb of bowel, and securing the mesh to the abdominal wall. Outcomes are reported for 102 patients undergoing robotic parastomal hernia repair from January 2021 to July 2023. Conversion to open surgery occurred in only one case (0.9%). Postoperative complications affected 39.2% of patients, with ileus being the most frequent (24.5%). Recurrence was observed in 5.8% of cases during an average follow-up of 10 months. In conclusion, parastomal hernia, a common complication post-stoma creation, demands surgical intervention. The robotic-assisted modified Sugarbaker repair technique, as outlined in this paper, offers promising results in terms of feasibility and outcomes.

Effect of previous abdominal surgery on robotic-assisted rectal cancer surgery.

BACKGROUND: The effect of previous abdominal surgery (PAS) in laparoscopic surgery is well known and significantly adds to longer hospital length of stay (LOS), postoperative ileus, and inadvertent enterotomies. However, little evidence exists in patients with PAS undergoing robotic-assisted (RA) rectal surgery. METHODS: All patients undergoing RA surgery for rectal cancer were reviewed. Patients with PAS were divided into minor and major PAS groups, defined as surgery involving >1 quadrant. The primary outcome was the risk of conversion to open surgery. RESULTS: A total of 750 patients were included, 531 in the no-PAS (NPAS) group, 31 in the major PAS group, and 188 in the minor PAS group. Patients in the major PAS group had significantly longer hospital LOS (P < .001) and lower adherence to enhanced recovery pathways (ERPs; P = .004). The conversion rates to open surgery were similar: 3.4% in the NPAS group, 5.9% in the minor PAS group, and 9.7% in the major PAS group (P = .113). Estimated blood loss (EBL; P = .961), operative times (OTs; P = .062), complication rates (P = .162), 30-day readmission (P = .691), and 30-day mortality (P = .494) were similar. Of note, 53 patients underwent lysis of adhesions (LOA). On multivariate analysis, EBL >500 mL and LOA significantly influenced conversion to open surgery. EBL >500 mL, age >65 years, conversion to open surgery, and prolonged OT were risk factors for prolonged LOS, whereas adherence to ERPs was a protector. CONCLUSION: PAS did not seem to affect the outcomes in RA rectal surgery. Given this finding, the robotic approach may ultimately provide patients with PAS with similar risk to patients without PAS.

Evolution of laparoscopic ileal pouch-anal anastomosis: impact of enhanced recovery program, medication changes, and staged approaches on outcomes.

BACKGROUND: Although laparoscopic Ileal pouch-anal anastomosis (IPAA) has become the gold standard in restorative proctocolectomy, surgical techniques have experienced minimal changes. In contrast, substantial shifts in perioperative care, marked by the enhanced recovery program (ERP), modifications in steroid use, and a shift to a 3-staged approach, have taken center stage. METHODS: Data extracted from our prospective IPAA database focused on the first 100 laparoscopic IPAA cases (historic group) and the latest 100 cases (modern group), aiming to measure the effect of these evolutions on postoperative outcomes. RESULTS: The historic IPAA group had more 2-staged procedures (92% proctocolectomy), whereas the modern group had a higher number of 3-staged procedures (86% proctectomy) (P < .001). Compared with patients in the modern group, patients in the historic group were more likely to be on steroids (5% vs 67%, respectively; P < .001) or immunomodulators (0% vs 31%, respectively; P < .001) at surgery. Compared with the historic group, the modern group had a shorter operative time (335.5 ± 78.4 vs 233.8 ± 81.6, respectively; P < .001) and length of stay (LOS; 5.4 ± 3.1 vs 4.2 ± 1.6 days, respectively; P < .001). Compared with the modern group, the historic group exhibited a higher 30-day morbidity rate (20% vs 33%, respectively; P = .04) and an elevated 30-day readmission rate (9% vs 21%, respectively; P = .02). Preoperative steroids use increased complications (odds ratio [OR], 3.4; P = .01), whereas 3-staged IPAA reduced complications (OR, 0.3; P = .03). ERP was identified as a factor that predicted shorter stays. CONCLUSION: Although ERP effectively reduced the LOS in IPAA surgery, it failed to reduce complications. Conversely, adopting a 3-staged IPAA approach proved beneficial in reducing morbidity, whereas preoperative steroid use increased complications.

The Impact of Enhanced Recovery on Long-Term Survival in Rectal Cancer.

INTRODUCTION: Implementing perioperative interventions such as enhanced recovery pathways (ERPs) has improved short-term outcomes and minimized length of stay. Preliminary evidence suggests that adherence to the enhanced recovery after surgery protocol may also enhance 5-year cancer-specific survival (CSS) in colorectal cancer surgery. This retrospective study presents long-term survival outcomes and disease recurrence from a high-volume, single-center practice. METHODS: All patients over 18 years of age diagnosed with rectal adenocarcinoma and undergoing elective minimally invasive surgery (MIS) were retrospectively reviewed between February 2005 and April 2018. Relevant data were extracted from Mayo electronic records and securely stored in a database. Short-term morbidity and long-term oncological outcomes were compared between patients enrolled in ERP and those who received non-enhanced care. RESULTS: Overall, 600 rectal cancer patients underwent MIS, of whom 320 (53.3%) were treated according to the ERP and 280 (46.7%) received non-enhanced care. ERP was associated with a decrease in length of stay (3 vs. 5 days; p < 0.001) and less overall complications (34.7 vs. 54.3%; p < 0.001). The ERP group did not show an improvement in overall survival (OS) or disease-free survival (DFS) compared with non-enhanced care on multivariable (non-ERP vs. ERP OS: hazard ratio [HR] 1.268, 95% confidence interval [CI] 0.852-1.887; DFS: HR 1.050, 95% CI 0.674-1.635) analysis. CONCLUSION: ERP was found to be associated with a reduction in short-term morbidity, with no impact on long-term oncological outcomes, such as OS, CSS, and DFS.

Re-Learning EXP3 Multi-Armed Bandit Algorithm for Enhancing the Massive IoT-LoRaWAN Network Performance.

Long-Range Wide Area Network (LoRaWAN) is an open-source protocol for the standard Internet of Things (IoT) Low Power Wide Area Network (LPWAN). This work's focal point is the LoRa Multi-Armed Bandit decentralized decision-making solution. The contribution of this paper is to study the effect of the re-learning EXP3 Multi-Armed Bandit (MAB) algorithm with previous experts' advice on the LoRaWAN network performance. LoRa smart node has a self-managed EXP3 algorithm for choosing and updating the transmission parameters based on its observation. The best parameter choice needs previously associated distribution advice (expert) before updating different choices for confidence. The paper proposes a new approach to study the effects of combined expert distribution for each transmission parameter on the LoRaWAN network performance. The successful transmission of the packet with optimized power consumption is the pivot of this paper. The validation of the simulation result has proven that combined expert distribution improves LoRaWAN network's performance in terms of data throughput and power consumption.

H2S Scavenging Capacity and Rheological Properties of Water-Based Drilling Muds.

Drilling hydrocarbon formations where hydrogen sulfide (H2S) is present could lead to the carryover of H2S with the drilling mud (i.e., drilling fluid) to the surface, exposing working personnel to this lethal gas. Additionally, H2S is very corrosive, causing severe corrosion of metal parts of the drilling equipment, which in turn results in serious operational problems. The addition of an effective H2S scavenger(s) in the drilling mud formulations will overcome these health, safety, and operational issues. In this work, zinc oxide (ZnO), which is a common H2S scavenger, has been incorporated into water-based drilling mud. The H2S scavenging performance of this ZnO-containing drilling mud has been assessed. Additionally, drilling mud formulations containing either copper nitrate (Cu(NO3)2·3H2O) or potassium permanganate (KMnO4) have been prepared, and their H2S scavenging performances have been studied and compared to that of the ZnO-containing drilling mud. It has been observed that the scavenging performance (in terms of the H2S amounts scavenged up to the breakthrough time and at the saturation condition) of the ZnO-containing drilling mud is very poor compared to those of the copper nitrate-containing and KMnO4-containing drilling muds. For instance, the amounts of H2S scavenged up to the breakthrough time by ZnO-containing, copper nitrate-containing, and KMnO4-containing drilling muds were 5.5, 15.8, and 125.3 mg/g, respectively. Furthermore, the amounts of H2S scavenged at the saturation condition by these drilling muds were, respectively, 35.1, 146.8, and 307.5 mg/g, demonstrating the superiority of the KMnO4-containing drilling mud. Besides its attractive H2S scavenging performance, the KMnO4-containing drilling mud possessed more favorable rheological properties [i.e., plastic viscosity (PV), yield point (YP), carrying capacity of the drill cuttings, and gelling characteristics] relative to the base and the ZnO-containing and copper nitrate-containing drilling muds. The addition of KMnO4 to the base drilling mud increased its apparent viscosity, PV, and YP by 20, 33, and 10%, respectively. Additionally, all tested drilling muds possessed acceptable fluid loss characteristics. To the best of our knowledge, there are so far no published studies concurrently tackling the H2S scavenging (i.e., breakthrough time, breakthrough capacity, saturation time, saturation capacity, and scavenger utilization) and the rheological properties of water-based drilling muds, as demonstrated in the current study, highlighting the novelty of this work.

Complex barite filter cake removal using in-situ generated acids by thermochemicals.

In sandstone formations, the quartz particles integrate with drilling fluid solids and become part of the filter cake structure. As a result, the dissolution rate of the filter cake diminishes and reduces the removal efficiency. This paper presents a novel solution to overcome the challenges that restricts the filter cake removal process such as the presence of the quartz layer and the polymer coat. A multi-stage method for removing the filter cake from a wellbore is presented. The composition of the new formulation is; ammonium fluoride (NH4F), with a strong oxidizer, such as sodium bromate (NaBrO3) causes an exothermic reaction in the first stage, thereby removing the quartz layer and polymer coat in the filter cake by the in-situ generated HF acid. During the second stage for the barite-based filter cake, chelating agents combined with convertor catalysts were used to dissolve the barite. Solubility experiments were conducted to evaluate the efficiency at each stage in the filter cake removal process at 300 ºF and 500 psi. The experimental results showed that the formulation consisting of ammonium fluoride (NH4F), with a strong oxidizer (sodium bromate,NaBrO3), combined with exothermic reaction was able to generate HF in-situ, which in turn dissolved the quartz mineral and remove the polymer from the filter cake.

Novel Approach for Sandstone Acidizing Using in Situ-Generated Hydrofluoric Acid with the Aid of Thermochemicals.

In this study, an in situ-generated hydrofluoric acid (HF) was used for sandstone acidizing, where an acid precursor (ammonium fluoride NH4F) reacted with a suitable oxidizer (sodium bromates NaBrO3) in an exothermic reaction. First, the new chemical mixture was prepared to react with pure quartz samples and the reaction effluent was analyzed to identify the presence of Si+ ions using the inductively coupled plasma (ICP) technique. Core flooding experiments were performed using Gray Berea sandstone cores (6 in. length and 1.5 in. diameter). A preflush stage of 5 PV of 7 wt % HCl was injected to remove any calcite content in the core. The main chemicals were then flushed for 3 successive cycles of 1 PV each. To assure core integrity, scratch tests and NMR scans were run on the core sample before and after the treatment. The new chemical mixture could dissolve the quartz sample and reduce its weight by 80 mg. The concentration of the dissolved Si+ ions was more than 90 ppm. This proves the capability of the chemical mixture to generate HF. The initial core permeability was measured at a stabilized flow rate of 2 cm3/min to be 33 mD. After the acid preflush stage, the core permeability reduced to 31 mD. Core permeability increased immediately after the first treatment cycle and reached 41 mD. At the end, the core flooding results showed a permeability improvement for Gray Berea sandstone cores by almost 40%. The ICP analysis of the effluent showed a total amount of chelated Si+ ions of about 10.5 mg. In addition to the high temperature generated in the near-wellbore area, the pressure increased because of the produced nitrogen gas from the exothermic reaction and reached about 600 psi. The scratch test showed an increase in the sample uniaxial compressive strength from 7432 to 9235 psi. The dynamic Poisson's ratio and the dynamic Young's modulus increased as well from 0.17 to 0.19 and from 2159 to 3585 ksi, respectively. The enhancement in the mechanical properties of the core can be attributed to the presence of the potassium element in Berea cores and its solidification reaction with the HF generated. The NMR measurements of the core sample before and after the acidizing process show an increase in the core porosity; however, the core preserved its original pore system. Upon application of this new stimulation technology, the true production potential of sandstone reservoirs can be achieved, well tubular corrosion will be minimized, and handling hazardous chemicals such as HF will be avoided. Most importantly, controlling the reaction rate, by controlling the amount of exothermic chemicals, can ensure deep acid penetration as well.