Development and applications of two and three component particle image velocimetry techniques for simultaneous measurement in multi-phase flows and automative fuel sprays

The introduction of a new imaging approach for simultaneous multi-phase and multi-constituent velocity measurements is the main focus of this research. The proposed approach is based on the use of a single off-the-shelf colour camera which will enable simultaneous imaging of phases/constituents which are colourtagged using fluorescent droplets and multi-wavelength illumination. Highly efficient florescent tracers used to seed the constituents are presented and their visibility in full field imaging experiments is evaluated. A commonly found problem in experimental systems using laser illumination, known as flare, is discussed and the application of the developed fluorescent tracers for its reduction is presented. A strong focus of the imaging approach proposed is its flexibility and simplicity allowing its extension to stereoscopic imaging to obtain simultaneous multi-phase/constituent 3-component measurements with the addition of a second imaging camera. Proof of principle experiments with spatially separated and well mixed flows are presented for which successful phase discrimination is obtained and the uncertainty of the measurements is estimated. The imaging system developed is applied for simultaneous air and fuel velocimetry measurements in a Gasoline Direct Injection spray for which a more detailed understating of the interaction mechanisms is required to generate improved designs. The modified imaging system and experimental setup are presented and previously unavailable simultaneous air/fuel 2 and 3-component velocity fields are presented and analysed.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Therapeutic Strategies and Oncological Outcome of Peritoneal Metastases from Lung Cancer: A Systematic Review and Pooled Analysis

The peritoneum is an unusual site of metastases from lung cancer, and optimal management at the moment remains unclear and mostly based on palliative strategies. Therefore, the aim of the study was to investigate demographic characteristics, management and overall survival of patients with peritoneal metastases from lung cancer (PCLC). A PRISMA-compliant systematic review and pooled analysis was performed searching all English studies published until December 2022. PROSPERO, CRD42022349362. Inclusion criteria were original articles including patients with peritoneal carcinomatosis from lung cancer, specifying at least one outcome of interest. Exclusion criteria were being unable to retrieve patient data from articles, and the same patient series included in different studies. Among 1746 studies imported for screening, twenty-one were included (2783 patients). Mean overall survival was between 0.5 and 5 months after peritoneal carcinomatosis diagnosis and 9 and 21 months from lung cancer diagnosis. In total, 27% of patients underwent first-line or palliative chemotherapy and 7% of them surgery. Management differs significantly among published studies. The literature on PCLC is scarce. Its incidence is low but appears to be substantially rising and is likely to be an underestimation. Prognosis is very poor and therapeutic strategies have been limited and used in a minority of patients. Subcategories of PCLC patients may have an improved prognosis and may benefit from an aggressive oncological approach, including cytoreductive surgery. Further investigation would be needed in this regar

Synchronous liver and peritoneal metastases from colorectal cancer: Is cytoreductive surgery and hyperthermic intraperitoneal chemotherapy combined with liver resection a feasible option?

BackgroundTraditionally, synchronous liver resection (LR), cytoreductive surgery (CRS), and hyperthermic intraperitoneal chemotherapy for colorectal liver and peritoneal metastases have been contraindicated. Nowadays, clinical practice has promoted this aggressive treatment in selected cases. This study aimed to review surgical and survival results of an extensive surgical approach including CRS with hyperthermic intraperitoneal chemotherapy (HIPEC) and LR. MethodsPubMed, EMBASE, and Web of Science databases were matched to find the available literature on this topic. The search period was limited to 10 years (January 2010-January 2021). A threshold of case series of 10 patients or more was applied. ResultsIn the search period, out of 114 studies found about liver and peritoneal metastases from colorectal cancer, we found 18 papers matching the inclusion criteria. Higher morbidity and mortality were reported for patients who underwent such an extensive surgical approach when compared with patients who underwent only cytoreductive surgery and HIPEC. Also, survival rates seem worse in the former than in the latter. ConclusionThe role of combined surgical strategy in patients with synchronous liver and peritoneal metastases from colorectal cancer remains controversial. Survival rates and morbidity and mortality seem not in favor of this option. A more accurate selection of patients and more restrictive surgical indications could perhaps help improve results in this subgroup of patients with limited curative options

Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study

Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk

Application of enhanced recovery after surgery (ERAS) protocols in adrenal surgery: A retrospective, preliminary analysis

Background: The present study was conducted to evaluate the impact of enhanced recovery after surgery (ERAS) pathway in patients undergoing laparoscopic adrenalectomy (LA) for primary and secondary adrenal disease, in reducing the length of primary hospital stay and return to daily activities. Materials and methods: This retrospective study was carried out on 61 patients who underwent LA. A total of 32 patients formed the ERAS group. A total of 29 patients received conventional perioperative care and were assigned as the control group. Groups were compared in terms of patient's characteristics (sex, age, pre-operative diagnosis, side of tumour, tumour size and co-morbidities), post-operative compliance (anaesthesia time, operative time, post-operative stay, post-operative numeric rating scale (NRS) score, analgesic assumption and days to return to daily activities) and post-operative complications. Results: No significant differences in anaesthesia time (P = 0.4) and operative time (P = 0.6) were reported. NRS score 24 h postoperatively was significantly lower in the ERAS group (P < 0.05). The analgesic assumption in post-operative period in the ERAS group was lower (P < 0.05). ERAS protocol led to a significantly shorter length of post-operative stay (P < 0.05) and to return to daily activities (P < 0.05). No differences in peri-operative complications were reported. Discussion: ERAS protocols seem safe and feasible, potentially improving perioperative outcomes of patients undergoing LA, mainly improving pain control, hospital stay and return to daily activities. Further studies are needed to investigate overall compliance with ERAS protocols and their impact on clinical outcomes

Laparoscopic versus Open Total Gastrectomy for Locally Advanced Gastric Cancer: Short and Long-Term Results

Background: Laparoscopic gastrectomy for early gastric cancer is widely accepted and routinely performed. However, it is still debated whether the laparoscopic approach is a valid alternative to open gastrectomy in advanced gastric cancer (AGC). The aim of this study is to compare short-and long-term outcomes of laparoscopic (LG) and open (OG) total gastrectomy with D2 lymphadenectomy in patients with AGC. Methods: A retrospective comparative study was conducted on patients who underwent LG and OG for ACG between January 2015 and December 2021. Primary endpoints were the following: recurrence rate, 3-year disease-free survival, 3-year and 5-year overall survival. Univariate and multivariate analysis was conducted to compare variables influencing outcomes and survival. Results: Ninety-two patients included: fifty-three OG and thirty-nine LG. No difference in morbidity and mortality. LG was associated with lower recurrence rates (OG 22.6% versus LG 12.8%, p = 0.048). No differences in 3-year and 5-year overall survival; 3-year disease-free survival was improved in the LG group on the univariate analysis but not after the multivariate one. LG was associated with longer operative time, lower blood loss and shorter hospital stay. Lymph node yield was higher in LG. Conclusion: LG for AGC seems to provide satisfactory clinical and oncological outcomes in medium volume centers, improved postoperative results and possibly lower recurrence rates

Definition of learning curve for thyroidectomy: systematic review on the different approaches

Background: Thyroidectomy is one of the most common surgical procedures carried out worldwide and it has evolved in recent years with alternative approaches. With the advent of minimally invasive techniques, the learning curve (LC) concept has become a fundamental "dogma". Methods: A literature search, according to the PRISMA guidelines, was performed via PubMed (MEDLINE), Scopus, Cochrane Library, EMBASE, Web of Science. Only studies assessing the learning process to thyroidectomy (including hemi-and total thyroidectomy), reporting a minimum of 30 procedures and describing clearly the minimum number of performances required to achieve proficiency and the main evaluation items used to establish it, were included. Conventional, endoscopic and robotic approaches were separately analyzed. Only English-language studies were considered. Results: Forty-five relevant studies were selected for the analysis (respectively 16 concerning RT, 22 ET, 6 MIVAT, 1 CT). The number of procedures required for a single surgeon to achieve competence and the parameters used to define surgical proficiency were fully investigated for each individual technique. Conclusions: Our research shows how the current literature lacks an objective definition of the LC concept. The heterogeneity of analysis methodologies and parameters evaluated, the various surgical techniques and training background of single surgeons, make it impossible to draw univocal results. Future studies should consider confounding factors and establish criteria that should be consensually recognized in the assessment of surgical performances and skills

Preoperative Transcatheter Arterial Embolization and En-Bloc Resection for Giant Non-Functioning Left Adrenocortical Carcinoma: A Case Report

Objective: To demonstrate efficacy and relative safety of compartment surgery in a case of large sized adrenocortical carcinoma (ACC), whenever associated with preoperative transcatheter arterial embolization (TAE) and adjuvant treatment with mitotane. Introduction: ACC is a rare illness; non-functioning lesions account for 40-55% of patients, may reach a large size, and show a clear attitude to infiltrate neighbouring organs. Case Report: Middle aged male visited for a huge left abdominal mass; contrast CT scan showed origin from the left adrenal lodge and possible extension of the tumor to surrounding structures. Preoperative adrenal work-up confirmed non-functioning nature of the adrenal mass. In order to allow a safe compartment excision and to decrease blood loss, preoperative angiography and TAE was performed. Patient underwent en-bloc resection of the mass, together with nephrectomy and distal splenopancreasectomy. No postoperative transfusions were required. Patient received adjuvant therapy with mitotane for 36 months since surgery, without any sign of tumor recurrence. Conclusion: An aggressive surgical approach seems justified also in locally advanced and infiltrating ACC; compartment resection is mandatory in order to obtain adequate resection margins. Preoperative TAE decreases intraoperative blood loss and need for transfusions. Adjuvant treatment with mitotane may contribute to reach remarkable disease-free survival

Ultrasound-guided Transversus Abdominis Plane Block is Effective as Laparoscopic Trocar site infiltration in Postoperative Pain Management in Patients Undergoing Adrenal Surgery

Background Pain management in patients undergoing laparoscopy is still a matter of debate as several techniques have been proposed to reduce postoperative analgesic consumption and improve recovery. Among these, transversus abdominis plane (TAP) block is considered as safe, effective, and easy to perform under ultrasound guidance; even so, recently laparoscopically guided trocar site anesthetic infiltration has been proposed as a "surgeon-dependent alternative to TAP block." The aim of this evaluation is to compare these analgesic techniques in the setting of laparoscopic adrenalectomy. Methods This is a retrospective evaluation of a prospectively maintained database. Patients were divided into two groups: Group A patients received laparoscopic-assisted trocar site infiltration of ropivacaine; Group B patients received bilateral ultrasound-guided TAP block with ropivacaine. All patients received 24 h infusion of 20 mg morphine postoperatively; pain was checked at 6, 24 and 48 h after surgery. A rescue analgesia was given if numerical rating scale (NRS) score was > 4 or on patient request. Results One hundred and three patients were enrolled in the evaluation (57 in group A and 46 in group B). There were no differences in operative time, complications and postoperative stay, and no complications related to trocar site infiltration. There were no differences in NRS at 6, 24, and 48 hours as well as in patients requiring further analgesic administration. Conclusions Laparoscopic-guided trocar site ropivacaine infiltration has similar pain outcomes compared to ultrasound-guided TAP block in the management of postoperative pain in patients undergoing laparoscopic adrenalectomy. Since there is no difference among these techniques, the decision can be based on surgeon or anesthesiologist preference

The neutrophil/lymphocyte ratio as a prognostic factor in COVID-19 patients: a case-control study

OBJECTIVE: SARS-CoV-2 (Se- vere Acute Respiratory Syndrome Coronavirus 2) has been identified in China as responsible for viral pneumonia, now called COVID-19 (Coro- navirus Disease 2019). Patients infected can de- velop common symptoms like cough and sore throat, and, in severe cases, acute respiratory syndrome and even death. To optimize the avail- able resources, it is necessary to identify in ad- vance the subjects that will develop a more se- rious illness, therefore requiring intensive care. The neutrophil / lymphocyte ratio (NLR) param- eter, resulting from the blood count, could be a significant marker for the diagnosis and man- agement of risk stratification. PATIENTS AND METHODS: A retrospective, single-center case-control observational study was conducted. The differential cell count of leu- kocytes, the NLR and the clinical course of pa- tients hospitalized in intensive care with COVID-19 were analyzed, comparing them with other pa- tients (COVID-19 and non-COVID-19) and healthy individuals selected among workers of the Teach- ing Hospital Policlinico Umberto I in Rome. RESULTS: 370 patients (145 cases and 225 controls) were included in the case-control study, 211 males (57%) and 159 females (43%). The average age of the population was 63 years (SD 16.35). In the group of cases, out of 145 pa- tients, 57 deaths and 88 survivors were record- ed, with a lethality rate of 39.3%. The group of cases has an NLR of 7.83 (SD = 8.07), a much higher value than the control group where an NLR of 2.58 was recorded (SD = 1.93) (p &lt;0.001). The Neutrophils / Lymphocytes ratio may prove to be a diagnostic factor for COVID-19, an NLR&gt; 3.68 revealed an OR 10.84 (95% CI = 6.47 - 18.13) (p &lt;0.005). CONCLUSIONS: The value of NLR considered together with the age variable allows a risk strat- ification and allows the development of diagnos- tic and treatment protocols for patients affect- ed by COVID-19. A high neutrophil to lymphocyte ratio suggests worse survival. Risk stratification and management help alleviate the shortage of medical resources and reduce the mortality of critically ill patients