Medical student hand preference, perceived dexterity, and impact of handedness on training.

BACKGROUND: The ubiquity of right-handed instruments and a predominance of right-handed surgical faculty present a challenge to left-handed trainees. Little is known about hand preference and its impact on specialty selection. We sought to evaluate hand preference, perceived dexterity, and impact of handedness on training among medical students. MATERIALS AND METHODS: A survey was distributed to third and fourth year medical students. Hand preference was queried for various activities. A Likert scale was used to assess perceived dexterity and impact of handedness on training. Fisher's exact test was used to compare groups. RESULTS: Of those queried, 131 (37%) responded. Handedness was defined by writing preference: right (80%), left (18%), other (2%). Left-handed students were more likely to perceive themselves to be ambidextrous (50% versus 15%; P < 0.001) and prefer their contralateral hand for at least one other activity (50% versus 4%; P < 0.001). Left-handed students were significantly more likely to report that handedness affected their specialty selection (33% versus 10%; P < 0.01) and training (58% versus 6%; P < 0.001). In addition, they reported that they would benefit from additional training with right-handed instruments (61% versus 31%; P < 0.01), availability of left-handed instruments (63% versus 8%; P < 0.001), and trainers who adapted to their handedness (70% versus 14%; P < 0.001). CONCLUSIONS: Left-handed medical students reported greater ambidexterity and adverse impact of handedness on training. These results provide a contemporary snapshot of hand preference in medical students and an argument for improving and adapting surgical training for left-handed individuals.

Predictors of Severity in Diabetic Foot Infections.

BACKGROUND: Diabetic foot infections (DFIs) constitute a large burden of the morbidity of diabetes, with more than 70,000 lower-extremity amputations (LEA) performed annually in the United States. A necrotizing infection signifies the most severe form of infection and is a key factor in the decision to proceed to LEA for source control. Key clinical and laboratory variables can assist in the identification of necrotizing infections; however, the effect of diabetes on these variables is unknown. Given the increased level and complexity of metabolic derangements in diabetic patients, we sought to examine characteristics predictive of necrotizing infection in patients with DFI who underwent LEA. METHODS: We performed a single-institutional retrospective analysis of diabetic patients who underwent a LEA for DFIs over an 18-month period. Patients with necrotizing infection on final pathology were compared with patients without this pathologic finding. Multivariate analysis was performed to identify independent predictors of necrotizing infection. RESULTS: Of 183 patients, 57 (31%) had evidence of necrotizing infections. Factors associated with necrotizing infection on univariate analysis were the presence of bullae (11% vs. 2%; odds ratio [OR] = 4.8, P = 0.03), a higher mean admission white blood cell count (WBC; 15 vs. 12, P = 0.002), a lower mean absolute sodium (132 vs. 134, P = 0.01), a higher hemoglobin A1C (11.3 vs. 10.3, P = 0.05), hyperglycemia (289 vs. 248, P = 0.04), elevated C-reactive protein (20 vs. 11, P = 0.02), and the presence of Pseudomonas aeruginosa on final tissue culture (12.3 vs. 1.6, P = 0.004). These patients were taken to surgery more rapidly (22.5 vs. 31 hr, P = 0.04), and they had a longer postoperative stay (7 vs. 4 days, P = 0.02). On multivariate analysis, an elevated WBC was predictive of necrotizing infection (OR = 1.1, P = 0.01), whereas alcohol use was found to be protective (OR = 0.3, P = 0.04). CONCLUSIONS: Clinical and laboratory variables known to be associated with necrotizing infections among the general population appear to be predictive of disease severity among patients undergoing amputation for DFIs. Identification of these abnormalities preoperatively may allow for improved operative planning, shared decision making, and resource management. Prospective validation of these findings is potentially warranted.

The effect of arginine vasopressin on organ donor procurement and lung function.

BACKGROUND: Hormone replacement therapy (HRT) is becoming more common when managing brain-dead donors. Arginine vasopressin (AVP) is associated with benefits but is not consistently used. We hypothesize that AVP is associated with the maintenance of lung function and successful recovery in donors and enhanced lung graft performance in recipients. METHODS: The Organ Procurement and Transplantation Network database was used. Study donors were those treated with HRT and procured from January 1, 2009 to June 30, 2011. AVP (+) and AVP (-) donors were compared. Donor lung function, the rate of successful lung procurement, and the incidence of graft failure in recipients were studied. RESULTS: There were 12,322 donors included, of which 7686 received AVP (62.4%). Cerebrovascular accident (4722 [38.3%]) was the most common cause of donor death. There was a significant increase in high yield (≥4 organs) (51.0% versus 39.3%, <0.001), mean number of organs (3.75 versus 3.33, <0.001), and rate of successful lung recovery (26.3% versus 20.5%, <0.001) with AVP. Lung function was preserved to a greater degree in donors receiving AVP. Adjusting the significant factors, AVP was independently associated with lung procurement (1.220 [1.114-1.336], <0.001). The incidence of early graft failure was not changed. CONCLUSIONS: AVP with HRT is associated with the maintenance of lung function and a significant increase in successful organ recovery in donors without untoward effects in the recipient. AVP should be universally adopted as a component of HRT in the management of donors with neurologic death.

Warfarin, not direct oral anticoagulants nor antiplatelet therapy, is associated with increased bleeding risk in emergency general surgery patients: implications in this new era of novel anticoagulants: An EAST Multicenter study.

INTRODUCTION: To assess perioperative bleeding complications & in-hospital mortality in patients requiring emergency general surgery (EGS) presenting with a history of antiplatelet (AP) vs. direct oral anticoagulant (DOAC) vs warfarin use. METHODS: Prospective observational study across 21 centers between 2019-2022. Inclusion criteria were age ≥ 18 years, & DOAC, warfarin or AP use within 24 hours of an EGSP. Outcomes included perioperative bleeding and in-hospital mortality. The study was conducted using ANOVA, Chi-square, and multivariable regression models. RESULTS: Of the 413 patients, 221 (53.5%) reported AP use, 152 (36.8%) DOAC use, & 40 (9.7%) warfarin use. Most common indications for surgery were obstruction (23% (AP), 45% (DOAC), 28% (warfarin)), intestinal ischemia (13%, 17%, 23%), & diverticulitis/peptic ulcers (7%, 7%, 15%). Compared to DOAC use, warfarin use was associated with significantly higher perioperative bleeding complication (OR 4.4 [2.0, 9.9]). There was no significant difference in perioperative bleeding complication between DOAC & AP use (OR 0.7 [0.4, 1.1]). Compared to DOAC use, there was no significant difference in mortality between warfarin use (0.7 [0.2, 2.5]) or AP use (OR 0.5 [0.2, 1.2]). After adjusting for confounders, warfarin use (OR 6.3 [2.8, 13.9]), medical history and operative indication were associated with an increase in perioperative bleeding complications. However, warfarin was not independently associated with risk of mortality (OR 1.3 [0.39, 4.7]), whereas intraoperative vasopressor use (OR 4.7 [1.7, 12.8)), medical history & postoperative bleeding (OR 5.5 [2.4, 12.8]) were. CONCLUSIONS: Despite ongoing concerns about the increase in DOAC use & lack of readily available reversal agents, this study suggests that warfarin, rather than DOACs, is associated with higher perioperative bleeding complications. However, that risk does not result in an increase in mortality, suggesting that perioperative decisions should be dictated by patient disease & comorbidities rather than type of antiplatelet or anticoagulant use.

Cdk1 targets Srs2 to complete synthesis-dependent strand annealing and to promote recombinational repair.

Cdk1 kinase phosphorylates budding yeast Srs2, a member of UvrD protein family, displays both DNA translocation and DNA unwinding activities in vitro. Srs2 prevents homologous recombination by dismantling Rad51 filaments and is also required for double-strand break (DSB) repair. Here we examine the biological significance of Cdk1-dependent phosphorylation of Srs2, using mutants that constitutively express the phosphorylated or unphosphorylated protein isoforms. We found that Cdk1 targets Srs2 to repair DSB and, in particular, to complete synthesis-dependent strand annealing, likely controlling the disassembly of a D-loop intermediate. Cdk1-dependent phosphorylation controls turnover of Srs2 at the invading strand; and, in absence of this modification, the turnover of Rad51 is not affected. Further analysis of the recombination phenotypes of the srs2 phospho-mutants showed that Srs2 phosphorylation is not required for the removal of toxic Rad51 nucleofilaments, although it is essential for cell survival, when DNA breaks are channeled into homologous recombinational repair. Cdk1-targeted Srs2 displays a PCNA-independent role and appears to have an attenuated ability to inhibit recombination. Finally, the recombination defects of unphosphorylatable Srs2 are primarily due to unscheduled accumulation of the Srs2 protein in a sumoylated form. Thus, the Srs2 anti-recombination function in removing toxic Rad51 filaments is genetically separable from its role in promoting recombinational repair, which depends exclusively on Cdk1-dependent phosphorylation. We suggest that Cdk1 kinase counteracts unscheduled sumoylation of Srs2 and targets Srs2 to dismantle specific DNA structures, such as the D-loops, in a helicase-dependent manner during homologous recombinational repair.

Anticoagulation in emergency general surgery: Who bleeds more? The EAST multicenter trials ACES study.

BACKGROUND: While direct oral anticoagulant (DOAC) use is increasing in the Emergency General Surgery (EGS) patient population, our understanding of their bleeding risk in the acute setting remains limited. Therefore, the objective of this study was to determine the prevalence of perioperative bleeding complications in patients using DOACs versus warfarin and AP therapy requiring urgent/emergent EGS procedures (EGSPs). METHODS: This was a prospective observational trial, conducted between 2019 and 2022, across 21 centers. Inclusion criteria were 18 years or older, DOAC, warfarin/AP use within 24 hours of requiring an urgent/emergent EGSP. Demographics, preoperative, intraoperative, and postoperative data were collected. ANOVA, χ 2 , and multivariable regression models were used to conduct the analysis. RESULTS: Of the 413 patients enrolled in the study, 261 (63%) reported warfarin/AP use and 152 (37%) reported DOAC use. Appendicitis and cholecystitis were the most frequent indication for operative intervention in the warfarin/AP group (43.4% vs. 25%, p = 0.001). Small bowel obstruction/abdominal wall hernias were the main indication for operative intervention in the DOAC group (44.7% vs. 23.8%, p = 0.001). Intraoperative, postoperative, and perioperative bleeding complications and in-hospital mortality were similar between the two groups. After adjusting for confounders, a history of chemotherapy (odds ratio [OR], 4.3; p = 0.015) and indication for operative intervention including occlusive mesenteric ischemia (OR, 4.27; p = 0.016), nonocclusive mesenteric ischemia (OR, 3.13; p = 0.001), and diverticulitis (OR, 3.72; p = 0.019) were associated with increased perioperative bleeding complications. The need for an intraoperative transfusion (OR, 4.87; p < 0.001), and intraoperative vasopressors (OR, 4.35; p = 0.003) were associated with increased in-hospital mortality. CONCLUSION: Perioperative bleeding complications and mortality are impacted by the indication for EGSPs and patient's severity of illness rather than a history of DOAC or warfarin/AP use. Therefore, perioperative management should be guided by patient physiology and indication for surgery rather than the concern for recent antiplatelet or anticoagulant use. LEVEL OF EVIDENCE: Prognostic and Epidemiologic; Level III.

Anticipated Transfusion Requirements and Mortality in Patients with Orthopedic and Solid Organ Injuries.

Long bone fractures are cited as an etiology for significant blood loss; however, there is scant supporting literature. We examined the relationship between long bone fractures, blood transfusions, and solid organ injuries. We hypothesize that transfusions are rare with long bone fractures in the absence of a liver or splenic injury. We performed a retrospective analysis of patients admitted with femur, tibia, and humerus fractures. Outcomes included transfusion requirements and mortality. A total of 1837 patients were included. There were 182 patients with at least one solid organ injury. A greater portion of patients with femur fractures and a lower proportion of patients with tibia fractures required transfusion. Adjusting for solid organ injuries, there was no difference in transfusions for any patient with these fractures compared with the group, or when grouped by organ injury severity. A solid organ injury significantly increases the risk of death among patients with long bone fractures. Blood loss requiring transfusion in patients with orthopedic and solid organ injuries should not be attributed to the presence of fractures alone. The need for transfusions in these patients should lower the threshold for reimaging or intervention for the solid organ injury. Further study is warranted to quantify blood loss by fracture type with or without solid organ.

Trends in organ donor management: 2002 to 2012.

BACKGROUND: Refinements in donor management have resulted in increased numbers and quality of grafts after neurologic death. We hypothesize that the increased use of hormone replacement therapy (HRT) has been accompanied by improved outcomes over time. STUDY DESIGN: Using the Organ Procurement and Transplant Network donor database, all brain-dead donors procured from July 1, 2001 to June 30, 2012 were studied. Hormone replacement therapy was identified by an infusion of thyroid hormone. An expanded criteria donor was defined as age 60 years or older. Incidence of HRT administration and number of donors and organs recovered were calculated. Using the Organ Procurement and Transplant Network thoracic recipient database transplant list, wait times were examined. RESULTS: There were 74,180 brain-dead donors studied. Hormone replacement therapy use increased substantially from 25.6% to 72.3% of donors. However, mean number of organs procured per donor remained static (3.51 to 3.50; p = 0.083), and the rate of high-yield donors decreased (46.4% to 43.1%; p < 0.001). Incidence of traumatic brain injury donors decreased (42.1% to 33.9%; p < 0.001) relative to an increased number of expanded criteria donors (22.1% to 26%). Despite this, there has been an increase in the raw number of donors (20,558 to 24,308; p < 0.001) and organs (5,857 to 6,945; p < 0.001). There has been an increase in organs per traumatic brain injury donor (4.02 to 4.12; p = 0.002) and a decrease in days on the waiting list (462.2 to 170.4 days; p < 0.001) for a thoracic transplant recipient. CONCLUSIONS: The marked increase in the use of HRT in the management of brain-dead donors has been accompanied by increased organ availability overall. Potential mechanisms might include successful conversion of previously unacceptable donors and improved recovery in certain subsets of donors.