ARTICLE | doi:10.20944/preprints202207.0361.v1
Subject: Medicine & Pharmacology, Anesthesiology Keywords: PSPS; FBSS; SCS; surgical lead; SCS implantation; MAST (for Minimal Access Spine Technologies); TCIVA (for Target Controlled Intra-Veinous Anesthesia); composite score; pain mapping; neuropathic pain; chronic pain; quality of life; anesthesia; hypnosis
Online: 25 July 2022 (08:34:26 CEST)
Spinal Cord Stimulation (SCS) is an effective and validated treatment to address chronic refractory neuropathic pain in Persistent Spinal Pain Syndrome-Type 2 (PSPS-T2) patients. Surgical SCS lead placement is traditionally performed under general anesthesia due to its invasiveness. In parallel, recent works have suggested that Awake Anesthesia (AA), consisting in Target Controlled Intra-Veinous Anesthesia (TCIVA), could be an interesting tool to optimize lead anatomical placement using patient intra-operative feedback. We hypothesized that combining AA with Minimal Invasive Surgery (MIS) could improve SCS outcomes. The goal of this study was to evaluate SCS lead performance (defined by the area of pain adequately covered by paraesthesia generated via SCS), using an intraoperative objective quantitative mapping tool, and secondarily to assess pain relief, functional improvement and change in quality of life with a composite score. We analyzed data from a prospective multicenter study (ESTIMET) to compare the outcomes of 115 patients implanted with MIS under AA (MISAA group) or General Anesthesia (MISGA group), or by Laminectomy under General Anesthesia (LGA group). All in all, MISAA appears to show significantly better performance in terms of patient pain coverage, as well as improved secondary outcomes. One step further, our results suggest that MISAA combined with intra-operative hypnosis could potentialize patient intraoperative cooperation and could be proposed as a personalized package offered to PSPS-T2 patients eligible for SCS implantation in highly dedicated neuromodulation centers.
ARTICLE | doi:10.20944/preprints202207.0451.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: sleep deficiency; insufficient sleep; surgery; surgical complications; attending surgeon; surgical outcomes
Online: 29 July 2022 (06:27:15 CEST)
Background: Sleep deficiency can adversely affect the performance of resident physicians resulting in greater medical errors. However, the impact of sleep deficiency on surgical outcomes, particularly among attending surgeons is less clear. Methods: Sixty attending surgeons from academic and community departments of surgery or obstetrics and gynecology were studied prospectively using direct observation and self-report to explore the effect of sleep deprivation on patient safety, operating room communication, medical errors, and adverse events while operating under two conditions, Post-Call (defined as >2 hours of nighttime clinical duties) and Non-Post-Call. Results: Each surgeon contributed up to five surgical procedures post-call and non-post-call yielding 362 cases total (150 Post-Call and 210 Non-Post-Call). Most common were caesarian section and herniorrhaphy. Hours of sleep on the night before the operative procedure were significantly less Post-Call (4.98 ± 1.41) vs. Non-Post-Call (6.68 ± 0.88, p<0.01). Errors were infrequent and not related to hours of sleep or post-call status. However, Non-Technical Skills for Surgeons (NOTSS) ratings demonstrated poorer performance while Post-Call for Situational Awareness, Decision Making and Communication/Teamwork. Fewer hours of sleep also was related to lower ratings for Situational Awareness and Decision Making. Decreased self-reported alertness was observed to be associated with increased procedure time. Conclusions: Sleep deficiency in attending surgeons was not associated with greater errors during procedures performed during the next day. However, procedure time was increased suggesting that surgeons were able to compensate for sleep loss by working more slowly. Ratings on non-technical surgical skills were adversely affected by sleep deficiency.
ARTICLE | doi:10.20944/preprints201909.0208.v1
Subject: Behavioral Sciences, Applied Psychology Keywords: surgical robotics; wearable force-sensor systems; grip-force profiling; surgical expertise; robot-assisted surgery training
Online: 18 September 2019 (13:07:40 CEST)
STRAS (Single access Transluminal Robotic Assistant for Surgeons) is a flexible robotic system based on the Anubis® platform of Karl Storz for application to intra-luminal surgical procedures. It consists of three cable-driven systems, one endoscope serving as guide and two inserted instruments. The flexible and bendable instruments have three degrees of freedom and can be teleoperated by a single user via two specially designed master interfaces. In this research, a pair of specific sensor gloves, which ergonomically fit to the master handles of the system was designed and the forces applied by one expert and one novice user during system-specific task execution in a simulator task (4-step-pick-and-drop) were compared. The results show that user expertise is not only reflected by shorter task execution times but also, more importantly, by specific differences in handgrip force profiles for specific sensor locations on anatomically relevant parts of the fingers and hand controlling the surgical instruments of the robotic master/slave system.
ARTICLE | doi:10.20944/preprints202204.0231.v1
Subject: Medicine & Pharmacology, Ophthalmology Keywords: glaucoma surgery; PRESERFLO; microshunt; surgical technique
Online: 26 April 2022 (06:15:10 CEST)
Purpose: To compare the standard implantation technique of a new ab externo microshunt (PRESERFLO) to a posterior technique with a small incision. The standard anterior approach (A) requires a relatively large, 6-8 mm perilimbal peritomy. In contrast, the posterior approach (P) involves only a 2-3 mm snip incision 2 mm posterior to the limbus. Methods: Charts of 126 PRESERFLO patients (54 A and 72 P) were retrospectively analyzed. Follow-up was 270 days. We compared the surgical time, intraocular pressure (IOP), number of medications, and complications. Results: The preoperative IOP in A was 21.8±8.5 mmHg and 23.9±8.1 mmHg in P (p=0.08). The surgical time for A was 26±0.8 minutes and 10±0.4 minutes for B (p<0.001). Following a low-pressure phase during the first week, A and P had an IOP value of 10.8±5.9 mmHg and 10.6±4.5 mmHg at 30 days, respectively (p=0.62). IOPs remained at this level throughout the study (all intra-group p> 0.08). There were no inter-group differences in IOP at any visit (all p-values > 0.3). Patients in A and P took 3.2 ± 1.3 and 3.3 ± 1.0 pressure-lowering medications at baseline, respectively (p=0.4). These values declined to 0.2 ± 0.6 in A and 0.3 ± 0.7 in P at 270 days. Both groups had a similar number of revisions (13 (10.3%) versus 10 (7.9%, p=0.14)) and complications (26 (20.8%) versus 31 (24.6%, all p>0.25). Conclusion: The posterior PRESERFLO insertion technique was 2.6 times faster than the standard anterior technique and yielded similar results with a large reduction in IOP and medications and a safety profile favorable over traditional filtering surgery.
ARTICLE | doi:10.20944/preprints202107.0022.v1
Subject: Medicine & Pharmacology, Allergology Keywords: thyroid neoplasm; thyroidectomy; robotic surgical procedures
Online: 1 July 2021 (11:30:12 CEST)
Objectives: Robotic bilateral axillary breast approach (BABA) thyroid surgery began in 2008 and is now one of the most widely used remote-access thyroid surgeries worldwide. This study aimed to analyze the results of 500 robotic BABA thyroid surgeries performed in a single institution in Korea compared with open thyroid surgery. Methods: From December 2018 to March 2020, 502 robotic BABA thyroidectomies (RTs) and 531 conventional open thyroidectomies (OTs) were performed in our institution by a single endocrine surgeon. We retrospectively reviewed patient medical records and performed a comparative analysis of OT and RT. Results: The RT group was younger (43.41±11.41 versus 54.28±13.41 years, p<0.001) and had a higher proportion of females (84.3% versus 69.3%, p<0.001), a lower BMI (24.66±3.97 versus 25.83±4.07 kg/m2), a higher proportion of lobectomies (52.6% versus 45.2%) and a lower proportion of lateral neck dissections (3.4% versus 10.0%, p<0.001). The RT group had a lnger operation time (145.33±40.80 versus 93.39±43.55 minutes, p<0.001) and higher surgical cost. Although the OT group had a larger tumor size and higher proportion of extrathyroidal extension, the numbers of retrieved lymph nodes were not significantly different between the two groups. Additionally, there was no difference in the stimulated thyroglobulin level before radioactive iodine therapy (7.01±35.73 versus 8.39±58.77, p=0.782). The rates of transient vocal cord palsy and transient hypoparathyroidism were significantly lower in the RT group, and those of scar-related complications were higher in the OT group. Conclusion: Robotic BABA thyroid surgery has advantages not only in better cosmetic outcomes but also in lower rates of vocal cord palsy and hypoparathyroidism, with comparable lymph node retrieval and serum thyroglobulin levels.
ARTICLE | doi:10.20944/preprints202207.0142.v1
Subject: Medicine & Pharmacology, General Medical Research Keywords: brachial plexus; traction injury; surgical treatment; electrostimulation
Online: 9 July 2022 (16:47:09 CEST)
As the problem of traction injuries to brachial plexus is a common one and of high socio-economic significance, the analysis of the surgical outcomes in patients with this pathology is significant for neurosurgery, neurology, traumatology-orthopedics, and rehabilitation. The aim of the research is to compare the short-term outcomes of using various surgical methods for managing patients with closed traction injuries of brachial plexus. Material and methods. The research involved 61 patients with closed traction injury of brachial plexus divided into two groups homogeneous in sex, age and severity of their neurological deficit: Group I – 33 patients who underwent microsurgical neurolysis, Group II – 28 patients who underwent microsurgical neurolysis combined with one-level electrostimulation. The dynamic assessment of clinical and functional status of upper limbs was performed using scale methods and electrophysiological monitoring. Results. The research revealed a more evident recovery of the upper limb function in Group II patients suggesting the method of microsurgical neurolysis combined with electrostimulation to be preferable in case of closed traction injuries to brachial plexus. Conclusion. The combination of microsurgical neurolysis with one-level electrostimulation improves the short-term outcomes of surgical treatment in patients with closed traction injuries of brachial plexus due to a sooner decrease in pain in postoperative period, and positive dynamics of clinical and electrophysiological parameters.
ARTICLE | doi:10.20944/preprints202107.0680.v1
Subject: Medicine & Pharmacology, Allergology Keywords: NEC; Surgical; Medical; Risk factor; Outcome; Neonate
Online: 30 July 2021 (09:11:09 CEST)
Background: Necrotizing enterocolitis (NEC) is one of the leading causes of death in newborns, however, little is understood of which patients can be treated medically or require surgery. The purpose of our study is to analyze the associated factors of surgically treated patients compared to patients requiring only medical treatment. Methods: Patients diagnosed with necrotizing enterocolitis over a period of 14 years in a single children’s hospital were retrospectively enrolled. Demographics and clinical data patients were collected and analyzed. Results: A total of 189 patients with NEC were included. Surgically treated patients had a lower gestational age (P = .018), body weight at birth (P = .034), and percentage of exclusive breast milk feeding (P= .001). They had increased comorbidity with respiratory distress syndrome (RDS) (P = .005), number of days of antibiotic use (P = .014), and length of hospital stay (P = .000). In multivariate logistic analysis, a lower percentage of exclusive breast milk feeding (OR = 0.366, 95% CI: 0.164-0.817) and a longer hospital stay (OR = 1.010, 95% CI: 1.001- 1.019) was associated with surgical NEC. Conclusion: Comparing medical and surgical NEC, a significantly lower percentage of surgical NEC patients were exclusively fed breast milk and their hospital stays were longer.
ARTICLE | doi:10.20944/preprints202107.0065.v1
Subject: Medicine & Pharmacology, Allergology Keywords: acromegaly; somatostatin analogues; presurgical treatment; surgical remission
Online: 2 July 2021 (14:52:23 CEST)
Purpose: To determine whether pre-surgical treatment using long-acting somatostatin analogues (SSAs) may improve surgical outcomes in acromegaly. Methods: Retrospective study of 48 patients with acromegaly operated by endoscopic transsphenoidal approach and for first time. Surgical remission was evaluated based on the 2010 criteria. Results: Most patients, 83.3% (n=40), harboured macroadenomas and 31.3% (n=15) invasive pitu-itary adenomas. Fourteen patients were treated with lanreotide LAR and 6 with octreotide LAR, median monthly doses of 97.5 [range 60-120] and 20 [range 20-30] mg, respectively, for at least 3 months preoperatively. Presurgical variables were comparable between pre-treated and un-treatred patients (P>0.05). Surgical remission was more frequent in those pre-treated with monthly doses ≥90 mg of lanre-otide or ≥30 mg of octreotide than in untreated or pre-treated with lower doses (OR=4.64, P=0.025). However, no differences were found between pre-treated and untreated patients when lower doses were included or between those treated for longer than 6 months compared to those untreated or pre-treated for shorter than 6 months. Similarly, no differences were found either in terms of surgical or endocrine complications (OR=0.65, P=0.570)), independently of the doses and the duration of SSA treatment (P>0.05). Conclusions: The dose of SSAs is a key factor during pre-surgical treatment, since the beneficial effects in surgical remission were observed with monthly doses equal or higher than 90 mg of lanreotide and 30 mg of octreotide, but not with lower doses.
ARTICLE | doi:10.20944/preprints202008.0061.v1
Online: 3 August 2020 (01:04:55 CEST)
Aims and Objectives: Our primary aim was to study association between nonsurgical techniques related complications and mortality and our secondary aim was to determine factors responsible for non surgical technique related complications. Material and Methods: All gastrointestinal and hepatobiliary procedures performed in last 3 years have been evaluated retrospectively. Nonsurgical procedure related postoperative complications were defined as perioperative complications nonrelated to surgical procedures or techniques and related to patients’ physiological health or comorbidities. To avoid selection bias in attempt to evaluate effect of non-surgical procedural related complication on mortality, we did 1:1 propensity score matching analysis with nonsurgical technique related complications as dependent factor. Propensity scores were calculated using logistic regression. Pre operative confounding factors like age, sex, American society of Anesthesia score (ASA), emergency surgery, type of surgeries like HPB surgeries, Upper gastrointestinal surgeries, small bowel surgeries, colorectal surgeries, hernia surgeries, open or laparoscopic surgeries were entered in model as covariates. We used nearest neighbor matching protocol with a calipher of 0.2. Cases were not reusable after matching. Statistical analysis was done using SPSS version 23. Results: Total 348 patients underwent various abdominal surgeries (gastrointestinal and hepatobiliary) in our department from April 2017 to March 2020. Total 24 patients developed nonsurgical technique related complications. Before Propensity score matching nonsurgical technique related complications were significantly higher in Upper Gastrointestinal surgeries (gastric and esophageal), emergency surgeries, Open surgeries, in patients who developed intraoperative hypotension, patients operated for malignancies, patients with higher ASA grades, patients in whom more blood products were used and patient who had more operative time. ASA scores independently predicted nonsurgical technique related complications. [P=0.001. Odds Ratio 3.955 (95% C.I.) 1.774-8.813)]. After Matching 24 patients patients were included in nonsurgical complication related complication group and they were compared with 23 matched controls. After matching also nonsurgical procedural related complications were significantly associated with mortality. (p< 0.0001). No intraoperative factors like intraoperative hypotension, blood product requirement, operative time predicted non-surgical technique related complication. Surgery related complications were not associated with mortality after matching. Conclusion: Nonsurgical technique related complications are associated with significant increase risk of mortality.
ARTICLE | doi:10.20944/preprints201907.0076.v1
Subject: Medicine & Pharmacology, Other Keywords: surgical site infection; breast surgery; breast implants; complications
Online: 4 July 2019 (11:32:17 CEST)
Purpose: Surgical site infection (SSI) is a significant complication of non-reconstructive and reconstructive breast. This study aimed to assess SSI after breast surgery over 5 years in a single center in Poland. The microorganisms responsible for SSI and their antibiotic susceptibility were determined. Materials/methods: Data of 2129 patients acquired over 5 years postoperatively by the [center] were analyzed. Results: SSI was diagnosed in 132 patients (6.2%) and was an early infection in most cases (65.2%). The incidence of SSI was highest in patients who underwent subcutaneous amputation with simultaneous reconstruction using an artificial prosthesis (14.6%) and breast reconstruction via the TRAM flap method (14.3%). Gram-positive bacteria were responsible for SSI in most cases (72.1%), and these were mainly Staphylococcus strains (53.6%). These strains were 100% susceptible to all beta-lactam antibiotics (except penicillin), but were less susceptible to macrolides and lincosamides. Conclusions: SSI is a serious problem, and attention should be focused on its prevention. Reconstruction using an artificial prosthesis or via the TRAM flap method is connected to increased SSI incidence. Further studies are required to prevent SSI following breast surgery.
ARTICLE | doi:10.20944/preprints202204.0175.v1
Subject: Engineering, Biomedical & Chemical Engineering Keywords: error; motor learning; surgical skills; EEG; fNIRS; neurovascular coupling
Online: 19 April 2022 (05:48:50 CEST)
Fundamentals of Laparoscopic Surgery (FLS) is a training module designed to provide basic surgical skills. During skill training of the FLS "suturing and intracorporeal knot-tying" task – the most difficult among the five psychomotor FLS tasks, learning from errors is one of the basic principles of motor skill acquisition where appropriate contextual switching of the brain state on error is postulated. This study investigated changes in the brain state following an error event based on the fusion of simultaneously acquired functional near-infrared spectroscopy (fNIRS) and electroencephalography (EEG) signals. Here, human error processing is postulated to differentiate experts from novices based on the differences in the error-related chain of mental processes. Thirteen right-handed novice medical students and nine expert surgeons participated in this study. Error-related microstate analysis was performed using 32-channel EEG data at a high temporal resolution. Six microstate prototypes were identified from combined EEG data from experts and novices during the FLS task. Analysis of variance (ANOVA) found that the proportion of the total time spent in different microstates during the 10 sec error epoch was significantly affected by the skill level (p<0.01), microstate type (p<0.01), and the interaction between the skill level and the microstate type (p<0.01). Then, the EEG band power (1-40Hz) related to slower oxyhemoglobin (HbO) changes were found using regularized temporally embedded Canonical Correlation Analysis of the fNIRS-EEG signals. The HbO signal from the fNIRS channel overlying ‘Frontal_Inf_Oper_L’, ‘Frontal_Mid_Orb_L’, ‘Postcentral_L’, ‘Temporal_Sup_L’, ‘Frontal_Mid_Orb_R’ cortical areas from Automatic Anatomical Labelling showed significant (p<0.05) difference between experts and novices in the 10-sec error epoch. Here, the frontal/prefrontal cortical areas are postulated to be related to the perception and the activation of the primary somatosensory cortex at the postcentral cortical area is hypothesized to be related to the action underpinning perception-action coupling model for the error-related chain of mental processes. Therefore, our study highlighted the importance of error-related brain states from portable brain imaging when comparing complex surgical skill levels.
REVIEW | doi:10.20944/preprints202109.0464.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: aesthetics; gingiva; hyaluronic acid; injections; surgical procedures; minimally invasive
Online: 28 September 2021 (11:08:28 CEST)
The absence of interdental papillae leads to the appearance of black triangle. For most patients, the appearance of these triangles is an important reason for concern and affects their social relationships. Multiple reconstruction techniques have been developed with different degrees of success and predictability. The main aim of this study was to evaluate the efficiency of hyaluronic acid (HA) injected into interproximal papillae six months after injection and to perform a systematic review and meta-analysis. After a systematic review, five articles were selected: a clinical randomised controlled trial and four clinical trials. In total, eighty-five patients with a deficiency in upper papillae in the front of the maxilla and jaw were included in the study. The height variable was evaluated (mm) six months after HA injection. In total, one hundred and four interproximal papillae were studied. Three articles showed an important difference in favour of intervention. The total result regarding in the injection of AH was favourable with an approximate average filling of 0.7 mm in the height of the interdental papilla. The injection of HA for the reconstruction of deficient papillae in the region of the upper and lower maxilla was a possible option treatment strategy.
ARTICLE | doi:10.20944/preprints202109.0436.v1
Online: 24 September 2021 (13:00:37 CEST)
Cesarean Section (CS) is one of the most frequently executed surgical procedures in gynecology and obstetrics. After a cesarean section, surgical site infection (SSI) increases hospital stay, lengthens maternal morbidity, and upsurges treatment costs. The current study determines the prevalence and risk factors for surgical site infection following cesarean section in China. A retrospective study was conducted on 23 cases of pregnant women who underwent cesarean section and incision severe infection and detection from March 2017 to January 2020 at Wuhan Maternal and Child Healthcare Hospital in China as the study group, and 20 cases of uninfected cesarean section during the same period were selected as the control group. Data were compared with the controls based on study variables and the presence of SSI. The mean age was 31±2.6. High fever and blood loss were observed in serous SSI-infected patients. The incidence rate of severe surgical site infection was 0.15 %. SSI was observed to be expected in pregnant women who had premature rupture of membrane before surgery (p < 0.001), who underwent postoperative antibiotic therapy (p < 0.001), and the patients who had gestational diabetes mellitus (p <0.001) and hematoma (p < 0.001) during surgery. Hence, following a cesarean section, surgical site infection is common. This research discovered several modifiable risk factors. SSI is associated with multifactorial rather than a single one. The development and strict implementation of a procedure by all health care practitioners can successfully reduce and prevent infection rates following cesarean section.
ARTICLE | doi:10.20944/preprints202004.0441.v1
Online: 24 April 2020 (12:06:33 CEST)
Background: The Corona Virus Disease 2019 (COVID-19) is spreading globally now. However, the clinical presentation that predict prognosis of the patients are still largely unknow. Methods: We enrolled 393 patients infected with COVID-19 and 30 patients with common pulmonary bulla and reviewed their clinical features to evaluate the potential prognostic value of pulmonary vesicles, especially in the patients with severe symptoms. One COVID-19 patient with vesicles was treated by bullectomy for last resort, and its characteristics of the patient’s perioperative laboratory tests was analyzed. The pathological findings of bullectomy were described and compared with those of common bulla cases. Results: Patients infected with COVID-19 showed more dependence on ventilator, occurrence of super resistant bacteria, and prone to vesicle formation than common bulla (p<0.05). Disease severity is associated with age, sex, and usage of ventilator, ECMO and antibiotics, super resistance bacteria and vesicle formation (p<0.05). The average mortality rate of COVID-19 patients was 4.10% (25.4% in severe patients, 0.00% in mild patients). Interestingly, the mortality rate further increased in severe patients with pulmonary vesicles than those without pulmonary vesicles (35.7% vs 22.4%, p=0.0442). One COVID-19 patient with vesicles underwent bullectomy and had a poor prognosis, who showed diffuse alveolar damage and extensive necrosis in bullectomy specimen. Conclusions: Patients infected with COVID-19 are more prone to form pulmonary vesicles showed on chest CT scans, as an important poor prognosis factor, especially in the severe patients.
ARTICLE | doi:10.20944/preprints202211.0178.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: Colo-rectal cancer; liver metastasis; simultaneous approach; surgical treatment; chemotherapy
Online: 9 November 2022 (15:36:13 CET)
Management of synchronous colorectal cancer with liver metastases (SCLM) is still on debate, regarding timing, indications and complications of the 3 strategies: classic approach (first tumor resection), simultaneous resection and reverse approach (liver first). A retrospective single-centre evaluation of synchronous approach was accomplished, focusing on surgical technique, indications and perioperative complications. Between 2017 and 2020, 31 SCLM patients benefited from synchronously colorectal and hepatic approach: segmental colectomies/rectal resections, simultaneously with liver metastasectomies (associated with radiofrequency ablation). Post-therapeutic imaging monitoring was performed from every 3 to 6 months. There were no perioperative complications related to the combination of the two procedures, low morbidity and zero postoperative mortality. The follow-up period was from 10 to 40 months: 13 patients had no evidence of recurrence, 10 patients had hepatic metastases in regression, 4 of them had signs of peritoneal carcinomatosis and 4 patients showed progression of liver disease; all patients were on chemotherapy. During follow-up 4 patients died. Experience shows that the simultaneous approach of recto-colic and hepatic resections in colo-rectal cancers is a safe procedure, with low morbidity, the limits being dictated by the size of the liver metastases. The results at long-distance must be drawn by further consistent trials.
ARTICLE | doi:10.20944/preprints202105.0207.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Suture material; Third molar surgery; Surgical wound infection; Bacterial adhesion
Online: 10 May 2021 (15:08:53 CEST)
Background: Selection and application of suture materials, has gained more importance especially with the increasing number of patients seeking oral surgeries. Since lying in a bacterial-filled environment, sutures make the tissue prone to infection. Suture material plays an important role in the reduction of the risk of infection. This study aimed to assess the success rate of an antibacterial suture named Vicryl Plus in preventing bacterial growth in the surgical site of the mandibular third molar. Methods: 27 patients were included in this double-blinded randomized clinical trial study. Surgical Extraction of the mandibular wisdom tooth was done and the incision was managed by randomly using Vicryl Plus and Vicryl sutures. After 7 days, sutures were removed and assessed microbiologically. Predominant species of Streptococcus mutans and Lactobacillus were assessed as well as the total number of colonies on each suture. Results: There was a significant difference between two suture materials in colony number-length ratio of lactobacillus (p-value= 0.031) and total bacterial colonies (p-value=0.016); but not for S. mutans species (p-value=0.201). Conclusion: Antibacterial Vicryl suture can be a useful tool for the reduction in the rate of surgical site infection in high-risk cases and situations.
ARTICLE | doi:10.20944/preprints202005.0317.v1
Subject: Medicine & Pharmacology, Gastroenterology Keywords: laproscopic cholecystectomy; acute cholecystitis; gall stone; sepsis; surgical site infection
Online: 20 May 2020 (04:16:36 CEST)
Aim: Aim of our study to evaluate various factors responsible for surgical site infection after gastrointestinal and hepatobiliary surgeries. Material and Methods: Patient who underwent gastrointestinal and hepatobiliary surgery in our department were evaluated retrospectively. Various factors associated with surgical site infection were evaluated using univariate and multivariate analysis. Surgical site infection was defined as any culture positive discharge from the wound within 30 days of surgery.Statistical analysis was done using SPSS version 23. Results: We evaluated total 331 patients operated between April 2018 to March 2020. 14 patients were lost to follow up after discharge and before completing post operative day 30. 18 patients expired before 30 days without developing SSI and were excluded from the study as per exclusion criteria. 299 patient included in the study. Total 20 patients developed surgical site infection. It showed SSI rate in our study population was 6.68%. On univariate analysis prolonged hospital stay, more blood product used, higher cdc grade of surgery, higher ASA grade, more operative time, open surgeries,colorectal and HPB surgeries were associated with surgical site infections. On multivariate analysis only prolonged hospital stay independently predicted Surgical Site Infectins. (p=0.014,0dds ratio 1.223, 95% confidence interal 1.042-1.435). Conclusion: Prolonged hospital stay independently predicts surgical site infections after gastrointestinal and hepatobiliary surgery.
CASE REPORT | doi:10.20944/preprints202210.0422.v1
Subject: Life Sciences, Biotechnology Keywords: Breast Augmentation; Reduction Mammoplasty; non-healing surgical wound; Wharton's jelly allograft
Online: 27 October 2022 (07:56:25 CEST)
Nearly 15 million patients undergo cosmetic surgery in the United States each year, with breast augmentations such as implants, lifts, or reductions being some of the most common procedures. The most common complications of these procedures are scarring and infection at the incision site, which often necessitates expensive corrective surgery. After significant weight loss, the patient in this study underwent an elective lower body lift in conjunction with a breast reduction and nipple-areolar transplant. An autologous skin graft was used at the transplant donor site. The skin graft unfortunately necrosed, warranting the need for rapid wound closure to avoid further pain and infection. The patient was treated for eight weeks with conservative measures. After eight weeks of failed attempts to close her wound, she was referred for specialist care. Upon initial examination, the donor site wound measured 3.5 cm x 3.5 cm with no sign of epithelialization. The patient received a single dose of Wharton’s jelly flowable perinatal tissue allograft and five hyperbaric oxygen therapy treatments over seven weeks. Upon inspection at the final examination, the wound was closed entirely with 100% epithelialization overlying granulation tissue. This case study demonstrates a precedent for the application of Wharton’s jelly flowable allografts in complicated cosmetic post-surgical wounds. Future efforts will be directed at applying Wharton’s jelly allografts on a preventative basis. Preventative applications could be in stage 2 pressure sores or intra-operatively to decrease potential patient suffering, prevent emotional distress, and reduce unnecessary healthcare expenses.
ARTICLE | doi:10.20944/preprints202102.0153.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: Surgical mask; exercise; treadmill test; stress test; Oxygen saturation; Covid19; ECG
Online: 5 February 2021 (10:03:09 CET)
In the context of the COVID-19 Pandemic, the use of surgical masks has become the new normal. The use of these devices in exercise and medical situations has been advocated with the purpose of reducing contagions, but some concerns exist regarding its safety. We performed maximal treadmill stress tests in 12 healthy young subjects, with and without surgical mask use, and measured exercise capacity, oxygen saturation (rest, peak exercise and post-exercise) and electrocardiographic changes. Exercise capacity and Oxygen saturation levels decreased in peak exercise vs rest in a statistically significant manner when mask was used. ECG changes, although not significant, were present in 3 subjects when mask was used and disappeared when the test was made unmasked. We conclude that masked exercise has the potential to cause decreased exercise load and oxygen saturation and potentially cause diagnostic errors in medical exams.
ARTICLE | doi:10.20944/preprints201707.0042.v1
Subject: Medicine & Pharmacology, Nursing & Health Studies Keywords: surgical smoke; volatile organic compounds (VOCs); health risk assessment (HRA); carcinogenic
Online: 17 July 2017 (07:40:18 CEST)
Surgical smoke is produced by energy-based surgical instruments. The airborne volatile organic compounds (VOCs) from surgical smoke may have potential health risk. This study aimed to evaluate the evidence for the harmful effects on the operating theater staff. An internationally recognized evaluation model of health risk assessment (HRA) was adapted to preliminarily assess the health risks caused by VOCs in surgical smoke. Results of HRA indicated that non-carcinogenic risk indexes of VOCs did not exceed one, indicating that these pollutants didn't cause significant non-carcinogenic harm to the health of the operating theater staff. But the cancer risk indexes exposed to formaldehyde and benzene all exceed 10-5, which was higher than the suggested value of USEPA (10-6) and might cause potential harm to the health of the operating theater staff. Long-term exposure of such surgical smoke will be harmful to the health of the operating theater staff and have a great risk of cancer.
ARTICLE | doi:10.20944/preprints201704.0142.v1
Subject: Medicine & Pharmacology, Oncology & Oncogenics Keywords: breast cancer; surgical tissues; gel-based proteomics; mass spectrometry; protein clustering
Online: 24 April 2017 (05:14:06 CEST)
The present investigation has been conducted on one hundred tissue fragments of breast cancer, collected and immediately cryopreserved following the surgical resection. The fragments were selected from patients with invasive ductal carcinoma of the breast, the most common and potentially aggressive type of mammary cancer, with the objective to increase the knowledge of breast cancer molecular markers, useful for diagnostic and prognostic categorization of patients, in assessing post-surgical therapeutic regimes. The proteomic screening, by 2D-IPG and mass spectrometry, allowed us to identify two main classes of protein clusters: proteins expressed ubiquitously at high levels in all patients, and proteins expressed sporadically among the same patients. Within the group of ubiquitous proteins, glycolytic enzymes and proteins with anti-apoptotic activity were predominant. Among the sporadic ones, proteins involved in cell motility, molecular chaperones and proteins involved in the detoxification appeared prevalent. The data of the present study indicates that the primary tumor growth is generally supported by two concurrent pathways: the inhibition of apoptosis and the stimulation of cellular proliferation. The second phase of the evolution of the tumor can be prematurely scheduled by the occasional presence of proteins involved in cell motility and in the defenses of the oxidative stress. To our knowledge this report on large-scales proteomics of breast cancer is currently a unique approach in the literature that offers the opportunity to evaluate the presence and recurrence of proteins to be used as prognostic indicators and susceptibility to metastasis in patients operated on for invasive ductal carcinoma of the breast.
ARTICLE | doi:10.20944/preprints202201.0326.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: Deep hypothermic circulatory arrest time; acute type A aortic dissection; surgical outcome
Online: 21 January 2022 (13:12:22 CET)
(1) Background: Deep hypothermic circulatory arrest (DHCA) with selective antegrade cerebral perfusion (ACP) is an established cerebral protection technique for the conduction of complex surgical procedures involving the aortic arch. It is controversial if the duration of DHCA is associated with adverse outcome in patients with acute type A aortic dissection (AAAD). Our goal was to investigate whether DHCA time was associated with surgical outcome in patients undergoing a surgical treatment of AAAD. (2) Methods: 410 Patients were divided into two groups concerning the DHCA time less than 60 minutes and equal or longer than 60 minutes. (3) Results: Patients with longer DHCA time were significantly younger (p=0.001). Intraoperatively, complex procedures with aortic arch surgery were more common in patients with longer DHCA time (p<0.001). Accordingly, cardiopulmonary bypass (p<0.001), cross-clamping (p<0.001) and DHCA times (p<0.001) were significantly longer in this group. Postoperatively, only the duration of mechanical ventilation (p<0.001) and the rate of tracheotomy were significantly higher in these patients. 30-day mortality was satisfactory for both groups (p=0.746). (4) Conclusions: Our results showed that improvements in perioperative management including ACP allow a successful performance of surgical treatment of AAAD under DHCA with duration of even longer than 60 minutes.
ARTICLE | doi:10.20944/preprints202106.0599.v2
Subject: Medicine & Pharmacology, Allergology Keywords: Clinical Study; Retrospective Studies; Surgical Procedures, Operative; Postoperative Period; Follow-Up Studies.
Online: 28 July 2021 (16:56:31 CEST)
Background In this study, we describe our clinical experience with the fifth-generation of a breast implant with a smooth, fine surface from a Korean manufacturer (BellaGelÒ SmoothFine; HansBiomed Co. Ltd., Seoul, Korea) in Asian women. Methods We analyzed 223 women (mean age=35.28±9.45 years and mean follow-up period=12.03±2.48 months), comprising 118 bilateral cases and 109 unilateral ones, who received breast augmentation using the BellaGelÒ SmoothFine at our hospital between June 4, 2018 and February 28, 2019. For safety assessment, we analyzed frequencies of postoperative complications and overall survival of the BellaGelÒ SmoothFine. Results Postoperatively, complications (12 cases, 5.38%) include asymmetry (3 cases, 1.35%), hematoma (2 cases, 0.90%), hypertrophic scars (2 cases, 0.90%), wound disruption (2 cases, 0.90%), rippling (1 case, 0.45%), capsular contracture (1 case, 0.45%), stretch deformities with skin excess (1 case, 0.45%). In addition, time-to-events were calculated as 10.94±0.64 months (95% CI 9.69-12.19) and the survival rate reached 0.290±0.168 (95% CI 0.094-0.901) at 12 months postoperatively. Conclusions Here, we describe our clinical experience with the BellaGelÒ SmoothFine. Our results are of significance in that this is the first report about the fifth-generation of a breast implant with a smooth, fine surface from a Korean manufacturer in Asian women.
ARTICLE | doi:10.20944/preprints202012.0556.v1
Subject: Medicine & Pharmacology, Allergology Keywords: Pancreatic cancer; recurrence; metastasis; surgical resection; circulating tumour cells; CTC; CellSearch; prognostication
Online: 22 December 2020 (12:02:41 CET)
In patients with presumed pancreatic ductal adenocarcinoma (PDAC), biomarkers that may open for personalised, risk-adapted treatment are lacking. The study analysed the impact of circulating tumour cells (CTCs) on the patterns of recurrence and survival in 98 patients resected for PDAC with 5-10 years of follow-up. Preoperative samples were analysed by the CellSearch® system for EpCAM+/DAPI+/CK+/CD45- CTCs. CTCs were detected in 7 of the 98 patients. CTCs predicted a significantly shorter median DFS of 3.3 vs. 9.2 months and a median CSS of 6.3 vs. 18.5 months. Relapse status was confirmed by imaging for 87 patients. Of these, 58 developed distant metastases (DM) and 29 cases isolated local recurrence (ILR) as first event. All patients with CTCs experienced DM. pN-status and histological grade >2 were other independent risk factors for DM, but only CTCs predicted significantly shorter cancer-specific, disease-free and post-recurrence survival. We conclude that CTC presence in resected PDAC patients predicted early distant metastasis and impaired survival. The impact of CTCs was comparable to that of histopathological risk factors and exceeded the effect size of other preoperative parameters. Thus, preoperative CTCs alone or in combination with histopathological factors may guide initial treatment decisions in patients with resectable PDAC in the future.
CASE REPORT | doi:10.20944/preprints202007.0183.v1
Subject: Medicine & Pharmacology, Dentistry Keywords: High frequency vibration; clear aligners; skeletal Class II; non-surgical treatment; malocclusion
Online: 9 July 2020 (11:45:30 CEST)
This study presents a novel technique utilizing high frequency vibration to shorten treatment time and preserve alveolar bone in challenging orthodontic cases treated with Invisalign® clear aligners. Four non-growing orthodontic patients (age range 14-47 years old) with Class II skeletal patterns (convex profiles with retrognathic mandibles) who sought correction of their crowded teeth and non-surgical correction of their convex profiles were included in this study. These patients were treated using Invisalign clear aligners together with high frequency vibration (HFV) devices (120 Hz) (VPro5™) that were used by all patients for five minutes per day during active orthodontic treatment. Vertical control and forward rotation of the mandible for each patient was achieved through pre-programming the Invisalign to produce posterior teeth intrusion. Successful forward rotation of the mandibles achieved in all patients led to improvement of their facial convex profiles (ANB improved 2.1 + 0.5 degrees; FMA improved 1.2 +1.1 degrees). Dental decompensation was achieved by lingual tipping of the lower incisors and palatal root torque of upper incisors. The use of HFV together with Invisalign facilitated achieving these results within a 12+6 month period. In addition, more bone labial to the lower incisors after their lingual movement was noted. In conclusion, the use of HFV concurrent with SmartTrack Invisalign aligners allowed complex tooth movement and forward projection without surgery in non-growing patients with skeletal Class II relationships. The clinical impact and implications of this case series is that the use of HFV facilitates complex orthodontic tooth movement including posterior teeth intrusion and incisor decompensation in addition to increased bone formation labial to lower incisors that may minimize future gum recession due to their labial inclination.
REVIEW | doi:10.20944/preprints202006.0109.v1
Subject: Medicine & Pharmacology, Other Keywords: surgery; surgical practice; COVID-19; pandemic; SARS-CoV-2; review; consensus; guidelines
Online: 7 June 2020 (16:38:30 CEST)
The coronavirus disease-2019 (COVID-19) pandemic is an ongoing pandemic caused by severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). Although COVID-19 pandemic is not a direct surgical problem, its impact on the surgical units has been substantial. Many operations have been cancelled or deferred due to risk of disease spread and staff shortages. Operating theatres are identified as areas of high risk of disease transmission due to aerosol generation during the surgical procedures and prolonged patient contact. Resource limitations, including lack of personal protective equipment (PPE) and limited availability of testing, continue to expose the surgical community to COVID-19. In this review, evidence and consensus guidelines on surgical practice during the COVID-19 pandemic are summarised and described. Immediate action is deemed essential to ensure unhindered provision of surgical care while optimizing the use of limited resources and ensuring staff safety.
ARTICLE | doi:10.20944/preprints202005.0339.v1
Subject: Medicine & Pharmacology, Urology Keywords: Neobladder-vaginal fistula; Orthotopic urinary diversion; Radical cystectomy; Surgical outcomes; Vaginal approach
Online: 21 May 2020 (09:32:33 CEST)
To present surgical methods and outcomes of neobladder-vaginal fistula (NVF) repair after radical cystectomy (RC) with ileal orthotopic neobladder (IONB). Methods: We retrospectively reviewed 136 women who underwent RC with IONB for bladder cancer between January 2010 and December 2018. The NVF was confirmed by cystoscopy and/or voiding cystography. NVF repair was performed using a transvaginal approach, which included circumferential incision of the fistula tract, creation of a plane between the neobladder serosa and the vaginal epithelium, and multi-layered transvaginal closure. Results: During a median follow-up of 47.9 months, NVF was identified in 12 (8.8%) women. Eight fistulas were located in the proximal anterior vaginal wall and four in the vaginal apex. Median time from RC to NVF repair was 3.4 months. Median NVF size and duration of urethral Foley catheter indwelling was 6.0 mm and 24.0 days, respectively. Initial repair of NVF was successful in ten (83.3%) patients. Two (16.7%) patients who relapsed retained IONB through the subsequent operation. Two (16.7%) patients developed urinary incontinence after NVF repair, requiring anti-incontinence surgery. Conclusions: The transvaginal approach for NVF repair is feasible, yielding successful surgical outcomes. However, women should be counseled about the risks of relapse and urinary incontinence.
ARTICLE | doi:10.20944/preprints201712.0010.v1
Subject: Engineering, Other Keywords: Hand Assisted Laparoscopic Surgery (HALS); sensing glove; wearable; collaborative surgical robot, gesture recognition.
Online: 1 December 2017 (16:32:22 CET)
This paper presents a system developed for the assistance with a collaborative robot in hand-assisted laparoscopic surgery (HALS). The system includes a sensing glove with piezoresistive sensors which capture continuously the flexion degree of the surgeon's fingers. These data are analyzed using an algorithm that detects and recognize the selected movements. This information is sent as commands to the collaborative robot throughout the surgical operation. The bending patterns, speed and execution times of the movements are modelled in a pre-phase in which it will extract all the necessary information for later detection during the motion execution. The results obtained with 10 different volunteers show a high degree of accuracy and a low false discovery rate.
REVIEW | doi:10.20944/preprints202204.0304.v1
Subject: Medicine & Pharmacology, Cardiology Keywords: Transcatheter aortic valve implantation; Surgical aortic valve replacement; Structural valve degeneration; Transcatheter heart valves
Online: 29 April 2022 (13:10:19 CEST)
Transcatheter aortic valve implantation (TAVI) has grown exponentially within the cardiology and cardiac surgical spheres. It has now become a routine approach for treating aortic stenosis. Several uncertainties have been raised about TAVI in comparison to conventional surgical aortic valve replacement (SAVR). The primary concerns are with regards to the longevity of the valves. Several factors have been identified that may predict poor outcomes following TAVI. These include the lesser-used finite element analysis (FEA) to quantify the properties of calcifications that affect TAVI valves. This can also be used in conjunction with other integrated software to ascertain the functionality of these valves. Other imaging modalities are now widely available such as Multi-detector row computed tomography(MDCT) which can accurately size the aortic valve annulus.. This may help reduce the incidence of paravalvular leaks and regurgitation which may necessitate further intervention. Structural valve degeneration (SVD) remains a key factor with varying results from current studies. The true incidence of SVD in TAVI compared to SAVR remains unclear with the lack of long term data. It is now widely accepted that both are part of the armamentarium and are not mutually exclusive. Decision-making for the appropriate intervention should be made via shared decision-making involving the heart team.
ARTICLE | doi:10.20944/preprints201810.0379.v1
Subject: Behavioral Sciences, Applied Psychology Keywords: surgical simulator training; individual performance trend; speed-accuracy function; automatic detection; performance feed-back
Online: 17 October 2018 (08:40:08 CEST)
Simulator training for image-guided surgical interventions may benefit from artificial intelligence systems that control the evolution of task skills in terms of time and precision of a trainee's performance on the basis of fully automatic feed-back systems. At the earliest stages of training, novice trainees frequently focus on getting faster at the task, and may thereby compromise the optimal evolution of the precision of their performance. For automatically guiding them towards attaining an optimal speed-accuracy trade-off, an effective control system for the reinforcement/correction of strategies must be able to exploit the right individual performance criteria in the right way, reliably detect individual performance trends at any given moment in time, and alert the trainee, as early as necessary, when to slow down and focus on precision, or when to focus on getting faster. This article addresses several aspects of this challenge for speed-accuracy controlled simulator training before any training on specific surgical tasks or clinical models should be envisaged. Analyses of individual learning curves from the simulator training sessions of novices and benchmark performance data of one expert surgeon, who had no specific training in the simulator task, validate the suggested approach.
REVIEW | doi:10.20944/preprints202011.0657.v2
Subject: Medicine & Pharmacology, Allergology Keywords: hypnosis; multimodal monitoring; entropy; qNOX; qCON; bispectral index; surgical plethismographic index; general anaesthesia; patient safety
Online: 25 January 2021 (17:02:57 CET)
With the development of general anesthesia techniques and anesthetic substances, brought new horizons for the expansion and improvement of surgical techniques. Nevertheless, more complex surgical procedures brought a higher complexity and longer duration for general anesthesia that led to a series of adverse events such as hemodynamic instability, under- or overdosage of anesthetic drugs, as well as an increased number of post-anesthetic events. In order to adapt the anesthesia according to the particularities of each patient, the multimodal monitoring of these patients is highly recommended. Classically, general anesthesia monitoring consists of the analysis of vital functions and gas exchange. Multimodal monitoring refers to the concomitant monitoring of the degree of hypnosis and the nociceptive-antinociceptive balance. By titrating anesthetic drugs according to these parameters, clinical benefits can be obtained, such as hemodynamic stabilization, reduction of awakening times, and the reduction of post-operative complications. Another important aspect is the impact on the status of inflammation and the redox balance. By minimizing inflammatory and oxidative impact one can achieve a faster recovery that will lead to both increased patient satisfaction and an increase in patient safety. The purpose of this literature review is to present the most modern multimodal monitoring techniques, respectively to discuss the particularities of each technique.
Subject: Keywords: Micro Hand S surgical robot system; robot-assisted complete mesocolic excision; colon cancer; safety; feasibility
Online: 1 March 2020 (02:54:29 CET)
Background: The Micro Hand S robot is the first domestically produced surgical robot that has entered clinical use in China, and this is the first report of its application in colon cancer. Objective: This study aimed to validate the safety and efficacy of the domestically produced Chinese minimally invasive Micro Hand S surgical robot system in complex surgery, such as robotic complete mesocolic excision (R-CME). Methods: From March 2018 to December 2018, 30 patients with right hemicolon cancer underwent R-CME with the Micro Hand S robot system. The operative findings, morbidities, oncological findings and unique characteristics were summarizedwere analyzed. Result: 12 patients with right hemicolon cancer and 18 patients with sigmoid colon cancer underwent RCME with the Micro Hand S robot system. During the study period, the median operative duration was 209 (range, 180-255) min, and the median estimated blood loss volume was 35 (range, 25-75) ml. The median number of lymph nodes harvested was 42 (21-77), and the median postoperative hospital stay was 5 (range, 4-7) days. According to the Clavien-Dindo classification, there were no severe complications except for 7 cases of grade I complications and 5 cases of grade II complications. The conversion rate for all operations was 0%. There were no cases of 30-day readmission or 30-day mortality. Conclusion: Clinical application of domestically produced Chinese minimally invasive surgical robot system “Micro Hand S ” in selected colon cancer patients is technically feasible and safe.
Subject: Medicine & Pharmacology, Gastroenterology Keywords: Micro Hand S surgical robot system; robot-assisted complete mesocolic excision; colon cancer; safety; feasibility
Online: 28 February 2020 (16:10:11 CET)
Background: The Micro Hand S robot is the first domestically produced surgical robot that has entered clinical use in China, and this is the first report of its application in colon cancer.Objective: This study aimed to validate the safety and efficacy of the domestically produced Chinese minimally invasive Micro Hand S surgical robot system in complex surgery, such as robotic complete mesocolic excision (R-CME).Methods: From March 2018 to December 2018, 30 patients with right hemicolon cancer underwent R-CME with the Micro Hand S robot system. The operative findings, morbidities, oncological findings and unique characteristics were summarizedwere analyzed.Result: 12 patients with right hemicolon cancer and 18 patients with sigmoid colon cancer underwent RCME with the Micro Hand S robot system. During the study period, the median operative duration was 209 (range, 180-255) min, and the median estimated blood loss volume was 35 (range, 25-75) ml. The median number of lymph nodes harvested was 42 (21-77), and the median postoperative hospital stay was 5 (range, 4-7) days. According to the Clavien-Dindo classification, there were no severe complications except for 7 cases of grade I complications and 5 cases of grade II complications. The conversion rate for all operations was 0%. There were no cases of 30-day readmission or 30-day mortality. Conclusion: Clinical application of domestically produced Chinese minimally invasive surgical robot system “Micro Hand S ” in selected colon cancer patients is technically feasible and safe.
CONCEPT PAPER | doi:10.20944/preprints202004.0133.v2
Subject: Life Sciences, Virology Keywords: ACE2, airborne; coronavirus; COV-2; COVID-19; food chain; intestinal infection; Kepler conjecture; rebound epidemic; packaging; particle size; SARS; surgical masks.
Online: 13 April 2020 (10:12:52 CEST)
Since there is not a clear consensus about the possibility for COVID-19 to be an airborne disease, exists a controversy regarding the need to use surgical masks to prevent its spread. Here, using the Kepler conjecture for ideal packaging, the number of virions of different sizes that can be accommodated inside droplets was calculated and are proportional to the 3rd potency of the droplet/virion diameter. The differences between particles of 5 um and 100 μm are around four orders of magnitude, explaining why the airborne spread is much more difficult but still possible. There is no solid evidence yet that the airborne coronaviruses may reach enough concentration to infect, but this may be the case under certain circumstances. The WHO partially recognizes now this fact in a warning to health workers (from my point of view too late, as it was the declaration of a pandemic). Another issue is whether the virus stays infective in aerosols generated from patients. This has not been directly proved yet except with artificial aerosols, but there are no reasons why the virus cannot remain in the air and be infective if the viral charge and time of exposure are enough. We must also consider whether the virus can infect the intestine; there are some signs in this sense. Finally, and most importantly, we need to reduce interactions by using surgical masks to flatten the curve, leave the quarantine and avoid a rebound. For cultural reasons, a social distance of 2 meters (2M) is extremely hard to manage. Surgical masks do reduce the interactions in conditions of proximity and, therefore, help to “flatten the curve”. The WHO and CDC “laissez-faire” on this matter do not help and we are running out of time. Anticipated actions, such as the use of surgical masks for the general population, are critical.
Subject: Life Sciences, Biochemistry Keywords: Head and Neck Squamous Cell Carcinoma (HNSCC); the Cancer Genome Atlas (TCGA); Survival Analysis; Optimal Cutoff; Surgical Margin; Holistic Cancer Care; Therapeutic Relationship; Mindfulness Meditation; Transcriptomic Analysis; Effect Size; CAMK2N1; CALML5; FCGBP
Online: 7 July 2021 (08:48:26 CEST)
The survival analysis of the Cancer Genome Atlas (TCGA) dataset is a well-known method to discover the gene expression-based prognostic biomarkers of head and neck squamous cell carcinoma (HNSCC). A cutoff point is usually used in survival analysis for the patients' dichotomization in the continuous gene expression. There is some optimization software for cutoff determination. However, the software's predetermined cutoffs are usually set at the median or quantiles of gene expression value to perform the analyses. There are also few clinicopathological features available on their pre-processed data sets. We applied an in-house workflow, including data retrieving and pre-processing, feature selection, sliding-window cutoff selection, Kaplan-Meier survival analysis, and Cox proportional hazard modeling for biomarker discovery. In our approach for the TCGA HNSCC cohort, we scanned human protein-coding genes to find optimal cutoff values. After adjustment with confounders, the clinical tumor stage and the surgical margin involvement are independent risk factors for patients' prognosis. According to the resulting tables with Bonferroni-adjusted P value under the optimal cutoff and the hazard ratio, three biomarker candidates, CAMK2N1, CALML5, and FCGBP, are significantly associated with the patients' overall survival. We validated this discovery by using the other independent HNSCC dataset (GSE65858). Thus, we suggest the transcriptomic analysis could help for biomarker discovery.