Correlation Between the Ratio of Oxygen Saturation to Fraction of Inspired Oxygen and the Ratio of Partial Pressure of Oxygen to Fraction of Inspired Oxygen in Detection and Risk Stratification of Pediatric Acute Respiratory Distress Syndrome.

OBJECTIVE: To measure the correlation between the ratio of oxygen saturation to fraction of inspired oxygen [SpO2/FiO2 (SF)] and the ratio of partial pressure of oxygen to fraction of inspired oxygen [PaO2/FiO2 (PF)] among children diagnosed with acute respiratory distress syndrome (ARDS). METHODOLOGY:  A cross-sectional study was conducted at the pediatric intensive care unit (PICU), National Institute of Child Health (NICH), Karachi, a tertiary care government hospital, from November 2020 to July 2021. One hundred twenty children (of either gender) having the age range of 2 months to 16 years, admitted to PICU with acute onset of respiratory distress, were included in the study. We measured SpO2, PaO2, FiO2 and calculated SF and PF ratios. SPSS (version 23) (Armonk, NY: IBM Corp) was used to analyze data, and the Spearmen's correlation test was applied to measure the relationship between SF and PF ratios. RESULTS: A total of 120 children were included, the mean age was 40.58±38.88 months and 67 (55.8%) were males. The mean FiO2 was 76.33%, the mean PaO2 and SpO2 were 100.35 mmHg and 94.37%, respectively. The mean PF ratio was 156.34, and the mean SF ratio was 156.45. There was a strong correlation between the SF ratio and the PF ratio (r=0.688; p=0.001). CONCLUSION: This study has shown that there is a strong correlation between the SF and PF ratios, and a statistically substantial agreement has been observed.

Stage Migration for Upper Tract Urothelial Cell Carcinoma.

INTRODUCTION: Upper tract urothelial carcinomas (UTUCs) account for 5% to 10% of urothelial cancers. The phenomenon of stage migration in tumors has been evident with increased use and higher resolution of cross-sectional imaging. Using the National Cancer Database, we analyzed trends in stage at presentation and overall survival for UTUCs. PATIENTS AND METHODS: We analyzed UTUCs in the renal pelvis or ureter from 2004 to 2016. Pathologic tumor stage data were available for 71.3% of patients and clinical tumor staging were available for 28.7% of patients. Five-year overall survival was analyzed comparing patients between 2004-2007 and 2008-2011. Tumor stage was categorized as early (0-1), intermediate (2-3), or late (4) for survival analyses. Linear regression and Kaplan-Meier analyses were utilized. RESULTS: A total of 37,210 renal pelvic and 23,200 ureteral origin UTUC cases were evaluated. Stage migration toward stage 0 and stage 4 was observed. There was a significant increase in proportion of stage 0 Ta/Tis (22.8%-33.4%, R2 = 0.86, P < .001) and stage 4 (22.3%-26.4%, R2 = 0.57, P = .003) disease for renal pelvic tumors, and a significant decrease in stages 1, 2, and 3. For UTUCs of ureteral origin, diagnosis at stage 0 Ta/Tis (37.6%-44.7%, R2 = 0.53, P = .005) and stage 4 (10.9%-14.6%, R2 = 0.63, P = .001) increased significantly, with significant reductions in stage 1 and 2. There was no difference in 5-year overall survival for ureteral or renal pelvic UTUCs for patients during 2004-2007 versus 2008-2011 when stratified by early, intermediate, or late stage. CONCLUSION: There is a stage migration toward stage 0 and stage 4 disease for UTUC. Five-year survival data from 2004 to 2011 remained stable across early, intermediate, and late stage groups.

Chemotherapy increases survival and downstaging of upper tract urothelial cancer.

INTRODUCTION: To evaluate the overall survival and pathologic downstaging effect of neoadjuvant chemotherapy for upper tract urothelial cell carcinoma. MATERIALS AND METHODS: The National Cancer Database (NCDB) was queried for patients with stage II-IV upper tract urothelial cell carcinoma undergoing definitive surgical resection (nephroureterectomy) from 2004-2015. Patients with metastatic disease were excluded. Cohorts were stratified by receipt of neoadjuvant chemotherapy (NAC). Kaplan-Meier analysis and Cox regression were used to evaluate overall survival. Logistic regression was used to predict the odds of pathologic downstaging to non-invasive disease (< pT2). Propensity score matched analysis was performed between groups. RESULTS: A total of 3634 patients were identified with non-metastatic stage II-IV disease undergoing surgical resection; 3364 received no chemotherapy and 270 received NAC. Patients undergoing NAC had a 10.9% rate of downstaging to non-invasive disease (OR 6.35, p < 0.001). Moreover, on Kaplan-Meier analysis, median survival was 27.3 months and 44.8 months for no chemotherapy versus NAC, respectively (log-rank, p = 0.001). Cox regression for death also revealed benefits for receiving NAC (HR 0.67, p < 0.001). Findings were confirmed on propensity score matching (532 matched patients). After matching, Cox regression for death noted improvement with neoadjuvant as compared to no chemotherapy (HR 0.61, p < 0.001). CONCLUSION: Neoadjuvant chemotherapy increases likelihood of downstaging to non-invasive disease in patients with upper tract urothelial cell carcinoma. Chemotherapy also provides an overall survival benefit in patients undergoing nephroureterectomy.

National Trends in the Utilization of Androgen Deprivation Therapy for Very Low Risk Prostate Cancer.

OBJECTIVE: To analyze national trends using the National Cancer Database (NCDB) in use of androgen deprivation therapy (ADT), outside of standard of care, in patients with very low risk prostate cancer. METHODS: We identified 52,797 men in the NCDB from 2010 to 2015 diagnosed with very low risk prostate cancer as defined (cT1cM0, PSA <10, Gleason ≤6, <3 biopsy cores positive). We evaluated the treatment trends and the proportion of men treated with ADT based on race, income, insurance status, treatment facility volume, and Charlson comorbidity. RESULTS: From 2010 to 2015, prevalence of primary ADT use in patients with very low risk prostate cancer remained 0.7%. Patients treated at low-volume facilities were more likely to receive primary ADT (hazard ratio [HR] 1.29, P <.001) as were black patients (HR 1.47, P <.001). When evaluated over time, the proportion of men treated with primary ADT who were white decreased while the proportion of men who were black increased. CONCLUSION: The use of primary ADT in men with very low risk prostate cancer has not changed over time, and may be over utilized, particularly among black men and those treated at low-volume facilities.

Trends in the treatment of clinical T1 renal cell carcinoma for octogenarians: Analysis of the National Cancer Database.

OBJECTIVE: Treatment of renal cell carcinoma has evolved with emphasis on nephron preservation for small renal masses. Our objective was to evaluate the proportions of treatment types for octogenarians with clinical stage 1 renal cell carcinoma. MATERIALS AND METHODS: The National Cancer Database was analyzed from 2004 to 2015. Patients with clinical stage 1, tumor size ≤ 7 cm, and age 80-89 years old were compared to a younger control arm of patients ≤ 70 years old. Treatment modality was categorized as radical nephrectomy (RN), partial nephrectomy (PN), percutaneous ablative therapy (PAT), and no treatment (NT). Primary outcome was treatment utilization over time using estimated annual percentage change (EAPC). Secondary outcomes included logistic regression for 30 day readmission after treatment and any definitive tumor treatment choice. RESULTS: 18,903 octogenarians were identified and compared to a control of 142,179 patients ≤ 70 years old. Overall, NT (36%) was the most common modality for octogenarians while PN (44.8%) was most common for the control arm. Using EAPC for octogenarians, we found increases for PAT (7.1%), PN (2.8%), and NT (1.6%) but a decrease for RN (-4.6%). EAPC for the younger cohort noted increases for PAT (6.8%), PN (5.4%), and NT (4.4%) but a decrease for RN (-5.5%). CONCLUSION: For octogenarians with stage 1 renal cell carcinoma, minimally invasive treatments are increasingly utilized, while RN is decreasing. Compared to a younger cohort, a greater proportion of octogenarians are receiving NT. These findings remain encouraging for appropriate treatment of localized disease in patients with advanced age.

Cognitive skills assessment during robot-assisted surgery: separating the wheat from the chaff.

OBJECTIVE: To investigate the utility of cognitive assessment during robot-assisted surgery (RAS) to define skills in terms of cognitive engagement, mental workload, and mental state; while objectively differentiating between novice and expert surgeons. SUBJECTS AND METHODS: In all, 10 surgeons with varying operative experience were assigned to beginner (BG), combined competent and proficient (CPG), and expert (EG) groups based on the Dreyfus model. The participants performed tasks for basic, intermediate and advanced skills on the da Vinci Surgical System. Participant performance was assessed using both tool-based and cognitive metrics. RESULTS: Tool-based metrics showed significant differences between the BG vs CPG and the BG vs EG, in basic skills. While performing intermediate skills, there were significant differences only on the instrument-to-instrument collisions between the BG vs CPG (2.0 vs 0.2, P = 0.028), and the BG vs EG (2.0 vs 0.1, P = 0.018). There were no significant differences between the CPG and EG for both basic and intermediate skills. However, using cognitive metrics, there were significant differences between all groups for the basic and intermediate skills. In advanced skills, there were no significant differences between the CPG and the EG except time (1116 vs 599.6 s), using tool-based metrics. However, cognitive metrics revealed significant differences between both groups. CONCLUSION: Cognitive assessment of surgeons may aid in defining levels of expertise performing complex surgical tasks once competence is achieved. Cognitive assessment may be used as an adjunct to the traditional methods for skill assessment during RAS.

Construct validation of the key components of Fundamental Skills of Robotic Surgery (FSRS) curriculum--a multi-institution prospective study.

BACKGROUND: Recent incorporation of simulation in surgical training necessitates developing validated platforms for training and assessment. A tool should fulfill the fundamental criteria of validation. OBJECTIVE: To report the ability of a simulation-based robotic training curriculum-Fundamental Skills of Robotic Surgery (FSRS)-to assess and distinguish between different performance levels of operator experience (construct validity). MATERIALS AND METHODS: This is a prospective multicenter observational study. Participants were classified as novice (0 robotic cases performed) and experts (>150 robotic cases performed). All participants were required to complete 4 key tasks in a previously validated FSRS curriculum: ball placement, coordinated tool control, fourth arm control, and needle handling and exchange. Using the metrics available in the simulator software, the performances of each group were compared to evaluate construct validation. RESULTS: A convenience cohort of 61 surgeons participated. Novice group (n = 49) consisted of 41 fellows/residents/medical students and 8 trained open/laparoscopic surgeons, whereas expert group consisted of 12 surgeons. The novice group had no previous robotic console experience, whereas the expert group had >150 prior robotic cases experience. An overall significant difference was observed in favor of the expert group in 4 skill sets (p < 0.05). Time to complete all 4 tasks was significantly shorter in the expert group (p < 0.001). The expert group displayed significantly lesser tool collision (p = 0.002) and reduced tissue damage (p < 0.001). In performing most tasks, the expert group's camera (p < 0.001) and clutch usage (p < 0.001) was significantly greater when compared with the novice group. CONCLUSION: The components of the FSRS curriculum showed construct validity. This validation would help in effectively implementing this curriculum for robot-assisted surgical training.

Novel knot tying technique for robot-assisted surgery.

Robot-assisted surgery has seen significant advancements in recent years, with dedicated training opportunities to acquire adequate skills. With improved degree of rotation and movement offered by the robot arm, newer techniques of knot tying need to be developed. Here we present a novel method of knot tying to help place a secure knot, especially with short suture length.