Trends in gastric surgery operative experience among general surgery residents in the United States: A nationwide retrospective analysis

BACKGROUND

Gastric surgery is a crucial component of general surgery training. However, there is a paucity of high-quality data on operative volume and the diversity of surgical procedures that general surgery residents are exposed to.

METHODS

We conducted a retrospective analysis of operative case logs of all general surgery residents graduating from the American College of Graduate Medical Education-accredited program from 2009 to 2022. Data on the mean number of gastric procedures, including the mean in each subcategory, were retrieved. A Mann-Kendall trend test was used to investigate trends in operative volume.

RESULTS

Between 2009 and 2022, the mean overall logged gastric procedures rose significantly (τ = 0.722, P < .001) from 36.2 in 2009 to 49.2 in 2022 (35.9% increase). The most substantial growth was seen in laparoscopic gastric reduction for morbid obesity (mean 1.9 in 2017 to 19 in 2022; τ = 0.670, P = .009). A statistically significant increase was also seen in laparoscopic partial gastric resections, repair of gastric perforation, and "other major stomach procedures" (P < .05 for all comparisons). Open gastrostomy, open partial gastric resections, and open vagotomy all significantly decreased (P < .05 for all comparisons). There was no significant change in the volume of laparoscopic gastrectomy, total gastric resections, and non-laparoscopic gastric reductions for morbid obesity (P > .05 for all comparisons).

CONCLUSION

There has been a substantial increase in the volume of gastric surgery during residency over the past 14 years, driven mainly by an increase in laparoscopic gastric reduction. However, there may still be a need for further gastric surgical training to ensure well-rounded general surgeons.

Don't Let the Sun Rise on Small Bowel Obstruction Without Surgical Consultation-Redefining Nonoperative Management Pathways

Introduction: Small bowel obstruction (SBO) is a common cause of hospital admission leading to resource utilization. The majority of these patients require non-operative management (NOM) which can lead to increased length of stay (LOS), readmissions, resource utilization, and throughput delays. Early surgical consultation (SC) for SBO may improve efficiency and outcomes. Methods: We implemented an institution-wide intervention (INT) to encourage early SC (<1 day of diagnosis) for SBO patients in July 2022. A retrospective analysis was performed on all patients with SBO requiring NOM from January 2021 to June 2023, categorized into pre- and post-INT groups. The primary outcome was the number of SC's and secondary outcomes were early SC (<1 day of diagnosis), utilization of SBFT, LOS, 30-day readmission, and costs of admission. Results: A total of 670 patients were included, 438 in the pre-INT and 232 in the post-INT group. Overall, SBFT utilization was significantly higher in cases with SC (17.2% vs 41.4%, P < .001). Post-INT patients were more likely to receive SC (94.0% vs 83.3%, P < .001) and increased SBFT utilization (47.0% vs 33.6%, P = .001). Additionally, early SC improved significantly in the post-INT group (74.3% vs 65.7%, P = .03). There was no difference in LOS between groups (4.0 vs 3.8 days, P = .48). There was a trend toward decreased readmission rates in the INT group at 30 days (7.3% vs 11.0%, P = .13) and reduced direct costs in the INT group (US$/admission = 8467 vs 8708, P = .1). Conclusion: Hospital-wide interventions to increase early surgical involvement proved effective by improving early SC, increased SBFT utilization, and showed a trend towards decreased readmission rates and direct costs.

Antithrombin III levels in critically ill surgical patients: do they correlate with VTE?

Objective

Antithrombin III (ATIII) deficiency may result from hereditary or acquired reduction in ATIII levels and is associated with an increase in venous thromboembolism (VTE) in the general population. VTE is a potentially preventable complication in the critically ill surgical patients. The objective of this study was to evaluate the relation between ATIII levels and VTE in surgical intensive care unit (SICU) patients.

Methods

All patients admitted to the SICU from January 2017 to April 2018 who had ATIII levels drawn were included in the study. An ATIII level below 80% of normal was considered low. The rate of VTE during the same admission was compared among patients with normal and low levels of ATIII. Prolonged length of stay (LOS >10 days) and mortality were also measured.

Results

Of the 227 patients included, 59.9% were male. The median age was 60 years. Overall, 66.9% of patients had low ATIII levels. Trauma patients had a higher rate of normal ATIII levels, whereas those weighing more than 100 kg had a higher rate of low ATIII levels. Patients with low ATIII levels had higher VTE rates compared with those with normal ATIII levels (28.9% vs. 16%, p=0.04). Patients with low ATIII levels also had prolonged LOS (76.3% vs. 60%, p=0.01) and increased mortality (21.7% vs. 6.7%, p<0.01). Trauma patients with VTE were more likely to have normal ATIII levels (38.5% in low ATIII cohort vs. 61.5% VTE in normal ATIII cohort, p<0.01).

Conclusion

Critically ill surgical patients with low ATIII levels have higher incidence of VTE, longer LOS, and higher mortality. In contrast, critically ill trauma patients may have high incidence of VTE even with normal ATIII levels.

Level of evidence

III.

Early Treatment With a Single Dose of Mesenchymal Stem Cell Derived Extracellular Vesicles Modulates the Brain Transcriptome to Create Neuroprotective Changes in a Porcine Model of Traumatic Brain Injury and Hemorrhagic Shock

BACKGROUND

Cell-based therapies using mesenchymal stem cell derived extracellular vesicles (EVs) improve neurologic outcomes in animal models of traumatic brain injury (TBI), stroke, and hemorrhage. Using a porcine 7-day survival model of TBI and hemorrhagic shock (HS), we previously demonstrated that EV-treatment was associated with reduced brain lesion size, neurologic severity score, and cerebral inflammation. However, the underlying cellular and genomic mechanisms remain poorly defined. We hypothesize that EV treatment modulates the brain transcriptome to enhance neuroprotection and neurorestoration following TBI + HS.

METHODS

Swine were subjected to severe TBI (8-mm cortical impact) and HS (40% blood volume). After 1 h of shock, animals were randomized (n = 4/group) to treatment with either lactated Ringer's (LR) or LR + EV. Both groups received fluid resuscitation after 2 h of shock, and autologous packed red blood cells 5 h later.After 7-days, brains were harvested and RNA-sequencing was performed. The transcriptomic data were imported into the iPathway pipeline for bioinformatics analyses.

RESULTS

5,273 genes were differentially expressed in the LR + EV group versus LR alone (total 9,588 measured genes). Genes with the greatest upregulation were involved in synaptic transmission and neuronal development and differentiation, while downregulated genes were involved in inflammation. GO-terms experiencing the greatest modulation were involved in inflammation, brain development, and cell adhesion. Pathway analysis revealed significant modulation in the glutamatergic and GABAergic systems. Network analysis revealed downregulation of inflammation, and upregulation of neurogenesis, and neuron survival and differentiation.

CONCLUSIONS

In a porcine model of TBI + HS, EV treatment was associated with an attenuation of cerebral inflammatory networks and a promotion of neurogenesis and neuroplasticity. These transcriptomic changes could explain the observed neuroprotective and neurorestorative properties associated with EV treatment.

Assessment of the Cytoprotective Effects of High-Dose Valproic Acid Compared to a Clinically Used Lower Dose

OBJECTIVE

Valproic acid (VPA) treatment improves survival in animal models of injuries on doses higher than those allowed by Food and Drug Administration (FDA). We investigated the proteomic alterations induced by a single high-dose (140mg/kg) of VPA (VPA140) compared to the FDA-approved dose of 30mg/kg (VPA30) in healthy humans. We also describe the proteomic and transcriptomic changes induced by VPA140 in an injured patient. We hypothesized that VPA140 would induce cytoprotective changes in the study participants.

METHODS

Serum samples were obtained from healthy subjects randomized to two groups; VPA140 and VPA30 at 3 timepoints: 0h(baseline), 2h, and 24h following infusion(n = 3/group). Samples were also obtained from an injured patient that received VPA140 at 0h, 6h and 24h following infusion. Proteomic analyses were performed using liquid chromatography-mass spectrometry (LC-MS/MS), and transcriptomic analysis was performed using RNA-sequencing. Differentially expressed (DE) proteins and genes were identified for functional annotation and pathway analysis using iPathwayGuide and gene set enrichment analysis (GSEA), respectively.

RESULTS

For healthy individuals, a dose comparison was performed between VPA140 and VPA30 groups at 2 and 24 h. Functional annotation showed that top biological processes in VPA140 versus VPA30 analysis at 2 h included regulation of fatty acid (P = 0.002) and ATP biosynthesis (P = 0.007), response to hypoxia (P = 0.017), cell polarity regulation (P = 0.031), and sequestration of calcium ions (P = 0.031). Top processes at 24 h in VPA140 versus VPA30 analysis included amino acid metabolism (P = 0.023), collagen catabolism (P = 0.023), and regulation of protein breakdown (P = 0.023). In the injured patient, annotation of the DE proteins in the serum showed that top biological processes at 2 h included neutrophil chemotaxis (P = 0.002), regulation of cellular response to heat (P = 0.008), regulation of oxidative stress (P = 0.008) and regulation of apoptotic signaling pathway (P = 0.008). Top biological processes in the injured patient at 24 h included autophagy (P = 0.01), glycolysis (P = 0.01), regulation of apoptosis (P = 0.01) and neuron apoptotic processes (P = 0.02).

CONCLUSIONS

VPA140 induces cytoprotective changes in human proteome not observed in VPA30. These changes may be responsible for its protective effects in response to injuries.

Cl-Amidine Improves Survival and Attenuates Kidney Injury in a Rabbit Model of Endotoxic Shock

Objective: Sepsis causes millions of deaths on a global scale annually. Activation of peptidylarginine deiminase (PAD) enzymes in sepsis causes citrullination of histones, which results in neutrophil extracellular trap formation and sepsis progression. This study evaluates pan-PAD inhibitor, Cl-amidine, in a model of lipopolysaccharide (LPS)-induced endotoxic shock in rabbits. We hypothesized that Cl-amidine would improve survival and attenuate kidney injury. Methods: In the survival model, rabbits were injected injected intravenously with 1 mg/kg of LPS, and then randomly assigned either to receive dimethyl sulfoxide (DMSO; 1 mcL/g) or Cl-amidine (10 mg/kg diluted in 1 mcL/g DMSO). They were then monitored for 14 days to evaluate survival. In the non-survival experiment, the same insult and treatment were administered, however; the animals were euthanized 12 hours after LPS injection for kidney harvest. Acute kidney injury (AKI) scoring was performed by a histopathologist who was blinded to the group assignment. Serial blood samples were also collected and compared. Results: Rabbits that received Cl-amidine had a higher survival (72%) compared with the rabbits that received DMSO (14%; p < 0.05). Cl-amidine-treated rabbits had lower (p < 0.05) histopathologic AKI scores, as well as plasma creatinine and blood urea nitrogen (BUN) levels 12 hours after insult. Conclusions: Pan-PAD inhibitor Cl-amidine improves survival and attenuates kidney injury in LPS-induced endotoxic shock in rabbits.

Pharmacologic modulation of brain metabolism by valproic acid can induce a neuroprotective environment

OBJECTIVE

Traumatic brain injury (TBI) is a leading cause of trauma-related morbidity and mortality. Valproic acid (VPA) has been shown to attenuate brain lesion size and swelling within the first few hours following TBI. Because injured neurons are sensitive to metabolic changes, we hypothesized that VPA treatment would alter the metabolic profile in the perilesional brain tissues to create a neuroprotective environment.

METHODS

We subjected swine to combined TBI (12-mm cortical impact) and hemorrhagic shock (40% blood volume loss and 2 hours of hypotension) and randomized them to two groups (n = 5/group): (1) normal saline (NS; 3× hemorrhage volume) and (2) NS-VPA (NS, 3× hemorrhage volume; VPA, 150 mg/kg). After 6 hours, brains were harvested, and 100 mg of the perilesional tissue was used for metabolite extraction. Samples were analyzed using reversed-phase liquid chromatography-mass spectrometry in positive and negative ion modes, and data were analyzed using MetaboAnalyst software (McGill University, Quebec, Canada).

RESULTS

In untargeted reversed-phase liquid chromatography-mass spectrometry analysis, we detected 3,750 and 1,955 metabolites in positive and negative ion modes, respectively. There were no significantly different metabolites in positive ion mode; however, 167 metabolite features were significantly different (p < 0.05) in the negative ion mode, which included VPA derivates. Pathway analysis showed that several pathways were affected in the treatment group, including the biosynthesis of unsaturated fatty acids (p = 0.001). Targeted amino acid analysis on glycolysis/tricarboxylic acid (TCA) cycle revealed that VPA treatment significantly decreased the levels of the excitotoxic amino acid serine (p = 0.001).

CONCLUSION

Valproic acid can be detected in perilesional tissues in its metabolized form. It also induces metabolic changes in the brains within the first few hours following TBI to create a neuroprotective environment.

Administration of valproic acid in clinically approved dose improves neurologic recovery and decreases brain lesion size in swine subjected to hemorrhagic shock and traumatic brain injury

BACKGROUND

Traumatic brain injury (TBI) and hemorrhage remain the leading causes of death after trauma. We have previously shown that a dose of valproic acid (VPA) at (150 mg/kg) can decrease brain lesion size and hasten neurologic recovery. The current Food and Drug Administration-approved dose of VPA is 60 mg/kg. We evaluate neurologic outcomes and brain lesion size of a single dose of VPA at a level currently within Food and Drug Administration-approved dose in swine subjected to TBI and hemorrhagic shock.

METHODS

Swine (n = 5/group) were subjected to TBI and 40% blood volume hemorrhage. Animals remained in shock for 2 hours before randomization to normal saline (NS) resuscitation alone (control), NS-VPA 150 mg/kg (VPA 150), or NS-VPA 50 mg/kg (VPA 50). Neurologic severity scores (range, 0-32) were assessed daily for 14 days, and brain lesion size was measured via magnetic resonance imaging on postinjury day (PID) 3.

RESULTS

Shock severity and laboratory values were similar in all groups. Valproic acid-treated animals demonstrated significantly less neurologic impairment on PID 1 and returned to baseline faster (PID 1 mean neurologic severity score, control = 22 ± 3 vs. VPA 150 mg/kg = 8 ± 7 or VPA 50 mg/kg = 6 ± 6; p = 0.02 and 0.003). Valproic acid-treated animals had significantly smaller brain lesion sizes (mean volume in mm3, control = 1,268.0 ± 241.2 vs. VPA 150 mg/kg = 620.4 ± 328.0 or VPA 50 mg/kg = 438.6 ± 234.8; p = 0.007 and 0.001).

CONCLUSION

In swine subjected to TBI and hemorrhagic shock, VPA treatment, in a dose that is approved for clinical use, decreases brain lesion size and reduces neurologic impairment compared with resuscitation alone.

Development of a large animal model of lethal polytrauma and intra-abdominal sepsis with bacteremia

Background

Trauma and sepsis are individually two of the leading causes of death worldwide. When combined, the mortality is greater than 50%. Thus, it is imperative to have a reproducible and reliable animal model to study the effects of polytrauma and sepsis and test novel treatment options. Porcine models are more translatable to humans than rodent models due to the similarities in anatomy and physiological response. We embarked on a study to develop a reproducible model of lethal polytrauma and intra-abdominal sepsis, which was lethal, though potentially salvageable with treatment.

Methods

Our laboratory has a well-established porcine model that was used as the foundation. Animals were subjected to a rectus crush injury, long bone fracture, liver and spleen laceration, traumatic brain injury and hemorrhage that was used as a foundation. We tested various colon injuries to create intra-abdominal sepsis. All animals underwent injuries followed by a period of shock, then subsequent resuscitation.

Results

All animals had blood culture-proven sepsis. Attempts at long-term survival of animals after injury were ceased because of poor appetite and energy. We shifted to an 8-hour endpoint. The polytrauma injury pattern remained constant and the colon injury pattern changed with the intention of creating a model that was ultimately lethal but potentially salvageable with a therapeutic drug. An uncontrolled cecal injury (n=4) group resulted in very early deaths. A controlled cecal injury (CCI; n=4) group had prolonged time prior to mortality with one surviving to the endpoint. The sigmoid injury (n=5) produced a similar survival curve to CCI but no animals surviving to the endpoint.

Conclusion

We have described a porcine model of polytrauma and sepsis that is reproducible and may be used to investigate novel treatments for trauma and sepsis.

Level of evidence

Not applicable. Animal study.

Higher Long-term Quality of Life Metrics After Video-Assisted Thoracoscopic Surgery Lobectomy Compared With Robotic-Assisted Lobectomy

BACKGROUND

Robotic-assisted thoracic surgery (RATS) lung lobectomy has emerged as an alternative approach to video-assisted thoracoscopic surgery (VATS). Patient-reported outcomes comparing these approaches have been limited.

METHODS

At a single, high-volume academic center, patients undergoing VATS and RATS lobectomies for stage I and II non-small cell lung cancer from 2014 to 2018 were evaluated. The European Organisation for Research and Treatment of Cancer Quality of Life of Cancer Patients Questionnaire (QLQ-C30) and Quality of Life Questionnaire in Lung Cancer (QLQ-LC13), along with the Fear of Recurrence (FoR) survey, were administered preoperatively and at 1, 6, and 12 months postoperatively. Raw scores underwent linear transformation (0-100 scale). Linear mixed-effects models were used for quality of life and FoR score comparisons.

RESULTS

The study included 219 patients (139 VATS and 80 RATS). RATS patients had longer (P < .05) operative times and a higher incidence (P < .05) of postoperative myocardial infarction compared to VATS patients. VATS patients reported higher (P < .05) QLQ-C30 summary scores postoperatively and at 12 months, including higher (P < .05) Social Functioning and Cognitive scores, and less (P < .05) appetite loss. VATS patients reported decreased (P < .05) QLQ-LC13 symptom summary scores at 6 months postoperatively, including decreased (P < .05) dyspnea, neuropathy, and pain compared with RATS patients. VATS patients also reported lower (P < .05) FoR summary scores at 6 months postoperatively.

CONCLUSIONS

VATS patients report improvement in select quality of life and FoR measures after lobectomy. Further study comparing these 2 approaches is required.

Inhibition of Histone Deacetylase 6 Protects Hippocampal Cells Against Mitochondria-mediated Apoptosis in a Model of Severe Oxygen-glucose Deprivation

Background:

Histone deacetylase (HDAC) 6 inhibitors have demonstrated significant protective effects in traumatic injuries. However, their roles in neuroprotection and underlying mechanisms are poorly understood. This study sought to investigate the neuroprotective effects of Tubastatin A (Tub-A), an HDAC6 inhibitor, during oxygenglucose deprivation (OGD) in HT22 hippocampal cells.

Methods:

HT22 hippocampal cells were exposed to OGD. Cell viability and cytotoxicity were assessed by cell counting kit-8 (CCK-8) and lactate dehydrogenase (LDH) release assay. Cellular apoptosis was assessed by Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. Mitochondria membrane potential was detected using JC-1 dye. Expressions of acetylated α-tubulin, α-tubulin, cytochrome c, VDAC, Bax, Bcl- 2, cleaved caspase 3, phosphorylated Akt, Akt, phosphorylated GSK3β and GSK3β were analyzed by Western blot analysis.

Results:

Tub-A induced acetylation of α-tubulin, demonstrating appropriate efficacy. Tub-A significantly increased cell viability and attenuated LDH release after exposure to OGD. Furthermore, Tub-A treatment blunted the increase in TUNEL-positive cells following OGD and preserved the mitochondrial membrane potential. Tub-A also attenuated the release of cytochrome c from the mitochondria into the cytoplasm and suppressed the ratio of Bax/Bcl-2 and cleaved caspase 3. This was mediated, in part, by the increased phosphorylation of Akt and GSK3β signaling pathways.

Conclusion:

HDAC 6 inhibition, using Tub-A, protects against OGD-induced injury in HT22 cells by modulating Akt/GSK3β signaling and inhibiting mitochondria-mediated apoptosis.

Histone Deacetylase Inhibition Attenuates Cardiomyocyte Hypoxia-Reoxygenation Injury

BACKGROUND

Cardiac reperfusion injury can have devastating consequences. Histone deacetylase (HDAC) inhibitors are potent cytoprotective agents, but their role in the prevention of cardiac injury remains ill-defined.

OBJECTIVE

We sought to determine the therapeutic potential of HDAC inhibitors in an in vitro model of cardiomyocyte hypoxia-reoxygenation (H/R).

METHOD

H9c2 cardiomyocytes were subjected to H/R and treated with various classspecific and pan-HDAC inhibitors in equal concentrations (5µM). Biological activity of inhibitors was determined, as a proxy for concentration adequacy, by Western blot for acetylated histone H3 and α-tubulin. Cell viability and cytotoxicity were measured by methyl thiazolyl tetrazolium and lactate dehydrogenase assays, respectively. Mechanistic studies were performed to better define the effects of the most effective agent, Tubastatin-A (Tub-A), on the phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) pathway effectors, and on the degree of autophagy.

RESULTS

All inhibitors acetylated well-known target proteins (histone H3 and α-tubulin), suggesting that concentrations were adequate to induce a biological effect. Improved cell viability and decreased cell cytotoxicity were noted in cardiomyocytes exposed to Tub-A, whereas the cytoprotective effects of other HDAC inhibitors were inconsistent. Pro-survival mediators in the PI3K/mTOR pathway were up-regulated and the degree of autophagy was significantly attenuated in cells that were treated with Tub-A.

CONCLUSION

HDAC inhibitors improve cell viability in a model of cardiomyocyte H/R, with Class IIb inhibition (Tub-A) demonstrating superior cellular-level potency and effectiveness. This effect is, at least in part, related to an increased expression of prosurvival mediators and a decreased degree of autophagy.

Comparative analysis of isoform-specific and non-selective histone deacetylase inhibitors in attenuating the intestinal damage after hemorrhagic shock

BACKGROUND

Isoform-specific histone deacetylase inhibitors (HDACIs) MC1568 and ACY1083 are comparable to the non-selective HDACI valproic acid (VPA) in improving survival in rodents undergoing lethal hemorrhage. However, the organ-specific properties of isoform-specific HDACIs have not been fully evaluated. Also, whether they can act synergistically is not known. We hypothesized that isoform-specific HDACIs are superior to VPA in attenuating intestinal injury and act synergistically when coadministered.

METHODS

Sprague Dawley rats were hemorrhaged (40% of total blood volume) and randomized to receive (n=4 per group) (1) MC1568 (5 mg/kg), (2) ACY1083 (30 mg/kg), (3) MC1568+ACY1083 (combination: 5 mg/kg + 30 mg/kg, respectively), (4) VPA (250 mg/kg), or (5) normal saline (NS; vehicle; 250 μL). Animals were observed for 3 hours, after which blood samples were collected and samples of the ileum were harvested. Expression of interleukin 1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), and cytokine-induced neutrophil chemoattractant 1 (CINC-1) was assessed in the tissues using enzyme-linked immunosorbent assay. Intestinal cleaved caspase 3 (c-caspase 3) levels were assessed as a marker of apoptosis, and histologic sections of the ileum were examined for signs of bowel injury. Levels of IL-1β and TNF-α were also measured in the serum as global markers of inflammation.

RESULTS

Treatments with MC1568, ACY1083, MC1568+ACY1083, and VPA were associated with decreased IL-1β levels in the intestine and serum compared with NS. IL-1β and TNF-α levels were significantly lower in the ACY1083 group compared with the VPA group. CINC-1 levels were significantly lower in the isoform-specific HDACI groups compared with the NS; however, no significant differences were seen with VPA. All treatment groups had a lower expression of intestinal c-caspase 3 compared with NS. Furthermore, MC1568 and ACY1083 groups had lower apoptosis compared with the VPA group. Bowel injury scores were significantly lower in the isoform-specific HDACI groups compared with the NS group; however, the attenuation in the VPA-treated animals did not reach statistical significance.

DISCUSSION

Isoform-specific HDACIs provide superior intestinal protection compared with VPA in a rodent model of hemorrhagic shock.

LEVEL OF EVIDENCE

Preclinical study.

The 'Omics' of Epigenetic Modulation by Valproic Acid Treatment in Traumatic Brain Injury-What We Know and What the Future Holds

Traumatic brain injury (TBI) is a heterogeneous injury that is a major cause of morbidity and mortality worldwide. Epigenetic modulation through the alteration of cellular acetylation by valproic acid (VPA) administration has shown promise as a novel pharmacological treatment for TBI. It improves clinical outcomes through multiple mechanisms, many of which are still poorly understood. In recent years, omics technologies have emerged as a promising strategy to detect molecular changes at the cellular level. This review highlights the use of these high throughput technologies in advancing the understanding of epigenetic modulation by VPA in TBI. It also describes the future role of omics techniques in developing a point of care test to guide patient selection for VPA administration.

The impact of intraoperative fluid management during laparoscopic donor nephrectomy on donor and recipient outcomes

BACKGROUND

Intraoperative fluid management during laparoscopic donor nephrectomy (LDN) may have a significant effect on donor and recipient outcomes. We sought to quantify variability in fluid management and investigate its impact on donor and recipient outcomes.

METHODS

A retrospective review of patients who underwent LDN from July 2011 to January 2016 with paired kidney recipients at a single center was performed. Patients were divided into tertiles of intraoperative fluid management (standard, high, and aggressive). Donor and recipient demographics, intraoperative data, and postoperative outcomes were analyzed.

RESULTS

Overall, 413 paired kidney donors and recipients were identified. Intraoperative fluid management (mL/h) was highly variable with no correlation to donor weight (kg) (R = 0.017). The aggressive fluid management group had significantly lower recipient creatinine levels on postoperative day 1. However, no significant differences were noted in creatinine levels out to 6 months between groups. No significant differences were noted in recipient postoperative complications, graft loss, and death. There was a significant increase (P < 0.01) in the number of total donor complications in the aggressive fluid management group.

CONCLUSIONS

Aggressive fluid management during LDN does not improve recipient outcomes and may worsen donor outcomes compared to standard fluid management.

Four-extremity amputation following disseminated intravascular coagulation and purpura fulminans

Purpura fulminans (PF) is a rare but serious complication of septic shock in adults. The complex disease course makes it challenging to manage the condition. Here, we present the case of a healthy young woman who presented with sepsis and new-onset erythematous lesions 4 days after the vaginal delivery of a healthy baby. The infectious source could not be identified, and the patient was started on antibiotics and resuscitated. However, her condition worsened, and she developed disseminated intravascular coagulation and PF. The septic episode slowly decreased in severity, but she sustained extensive ischaemic injuries to her extremities, for which she underwent four-limb amputation.

Traumatic brain injury may worsen clinical outcomes after prolonged partial resuscitative endovascular balloon occlusion of the aorta in severe hemorrhagic shock model

BACKGROUND

The use of partial resuscitative endovascular balloon occlusion of the aorta (pREBOA) in combined hemorrhagic shock (HS) and traumatic brain injury (TBI) has not been well studied. We hypothesized that the use of pREBOA in the setting of TBI would be associated with worse clinical outcomes.

METHODS

Female Yorkshire swine were randomized to the following groups: HS-TBI, HS-TBI-pREBOA, and HS-pREBOA (n = 5/cohort). Animals in the HS-TBI group were left in shock for a total of 2 hours, whereas animals assigned to pREBOA groups were treated with supraceliac pREBOA deployment (60 minutes) 1 hour into the shock period. All animals were then resuscitated, and physiologic parameters were monitored for 6 hours. Further fluid resuscitation and vasopressors were administered as needed. At the end of the observation period, brain hemispheric swelling (%) and lesion size (mm) were assessed.

RESULTS

Mortality was highest in the HS-TBI-pREBOA group (40% [2/5] vs. 0% [0/5] in the other groups, p = 0.1). Severity of shock was greatest in the HS-TBI-pREBOA group, as defined by peak lactate levels and pH nadir (p < 0.05). Fluid resuscitation and norepinephrine requirements were significantly higher in the HS-TBI-pREBOA group (p < 0.05). No significant differences were noted in brain hemispheric swelling and lesion size between the groups.

CONCLUSION

Prolonged application of pREBOA in the setting of TBI does not contribute to early worsening of brain lesion size and edema. However, the addition of TBI to HS-pREBOA may worsen the severity of shock. Providers should be aware of the potential physiologic sequelae induced by TBI.

Protective Effect of Tubastatin A in CLP-Induced Lethal Sepsis

We have found earlier that Tubastatin A (TubA), a selective inhibitor of histone deacetylase 6 (HDAC6), improves survival in a mouse model of lethal cecal ligation and puncture (CLP)-induced sepsis. However, the underlying mechanisms have not been fully established. This study sought to test the hypothesis that TubA could affect both lung and splenic functions. C57BL/6J mice were subjected to CLP, and randomized to receive either TubA (70 mg/kg) dissolved in dimethyl sulfoxide (DMSO), or DMSO alone, 1 h following CLP. Sham animals acted as control. Twenty-four hours later, lung tissue was harvested for pathological examination, and splenic tissue was harvested for bacterial colonization. In a parallel study, the spleen was collected 48 h following CLP, and single cell suspension was prepared. Splenocytes then underwent flow cytometry to analyze the immune cell population. RAW264.7 macrophages were treated with lipopolysaccharide (LPS) with or without the presence of TubA (10 μM) at 37 °C for 3 h to assess the effect on macrophage phagocytosis. We found that acute lung injury secondary to lethal sepsis was attenuated by TubA. Treatment with TubA restored the percentage of B lymphocytes, and significantly increased percentages of innate immune cells and macrophages compared to the vehicle-treated CLP group. Moreover, TubA significantly decreased the bacterial load in the spleen, and improved the phagocytic ability of RAW264.7 murine macrophages in vitro. Such findings may help to explain the beneficial effects of TubA treatment in a model of lethal sepsis, as previously reported.

Resident perceptions and evaluations of fellow-led and resident-led surgical services

BACKGROUND

The impact of fellowship training on general surgery residency has remained challenging to assess. Surgical resident perceptions of fellow-led and resident-led surgical services have not been well described.

METHODS

Retrospective cross-sectional data were collected from residents' service evaluations from 7/2014 through 7/2017. Surgical services were categorized as resident-led or fellow-led. 31 variables were evaluated and collapsed into 7 factors including clinical experience, educational experiences, clinical staff, workload, feedback, treatment of residents, and overall rotation.

RESULTS

Among all PGY levels, fellow-led surgical services were rated significantly higher (p < 0.05) regarding clinical experience, clinical staff, treatment of residents, and overall rotation. PGY1-2 residents rated resident-led services significantly higher in the area of educational experiences, while PGY 3 residents rated resident-led services higher in the area of workload. However, PGY4-5 residents rated fellow-led services significantly higher in all 7 categories. Individual fellow-led services were rated significantly higher for various categories at different PGY levels.

CONCLUSIONS

Surgical residents appear to value the educational experiences of fellow-led services. Each fellow-led service may ultimately provide unique educational opportunities and resources for different PGY levels.

Complete and Partial Aortic Occlusion for the Treatment of Hemorrhagic Shock in Swine

Hemorrhage remains the leading cause of preventable deaths in trauma. Endovascular management of non-compressible torso hemorrhage has been at the forefront of trauma care in recent years. Since complete aortic occlusion presents serious concerns, the concept of partial aortic occlusion has gained a growing attention. Here, we present a large animal model of hemorrhagic shock to investigate the effects of a novel partial aortic balloon occlusion catheter and compare it with a catheter that works on the principles of complete aortic occlusion. Swine are anesthetized and instrumented in order to conduct controlled fixed-volume hemorrhage, and hemodynamic and physiological parameters are monitored. Following hemorrhage, aortic balloon occlusion catheters are inserted and inflated in the supraceliac aorta for 60 min, during which the animals receive whole-blood resuscitation as 20% of the total blood volume (TBV). Following balloon deflation, the animals are monitored in a critical care setting for 4 h, during which they receive fluid resuscitation and vasopressors as needed. The partial aortic balloon occlusion demonstrated improved distal mean arterial pressures (MAPs) during the balloon inflation, decreased markers of ischemia, and decreased fluid resuscitation and vasopressor use. As swine physiology and homeostatic responses following hemorrhage have been well-documented and are like those in humans, a swine hemorrhagic shock model can be used to test various treatment strategies. In addition to treating hemorrhage, aortic balloon occlusion catheters have become popular for their role in cardiac arrest, cardiac and vascular surgery, and other high-risk elective surgical procedures.

Mesenchymal Stem Cell-Derived Exosomes Provide Neuroprotection and Improve Long-Term Neurologic Outcomes in a Swine Model of Traumatic Brain Injury and Hemorrhagic Shock

Combined traumatic brain injury (TBI) and hemorrhagic shock (HS) remains a leading cause of preventable death worldwide. Mesenchymal stem cell-derived exosomes have demonstrated promise in small animal models of neurologic injury. To investigate the effects of exosome treatment in a clinically realistic large animal model, Yorkshire swine underwent TBI and HS. Animals were maintained in shock for 2 h before resuscitation with normal saline (NS). Animals were then resuscitated either with NS (3 × volume of shed blood) or with the same volume of NS with delayed exosome administration (1 × 10¹³ particles/4 mL) (n = 5/cohort). Exosomes were administered 9 h post-injury, and on post-injury days (PID) 1, 5, 9, and 13. Neurologic severity scores (NSS) were assessed for 30 days, and neurocognitive functions were objectively measured. Exosome-treated animals had significantly lower NSS (p < 0.05) during the first five days of recovery. Exosome-treated animals also had a significantly shorter time to complete neurologic recovery (NSS = 0) compared with animals given NS alone (days to recovery: NS = 16.8 ± 10.6; NS + exosomes = 5.6 ± 2.8; p = 0.03). Animals treated with exosomes initiated neurocognitive testing earlier (days to initiation: NS = 9.6 ± 0.5 vs. NS + exosomes = 4.2 ± 0.8; p = 0.008); however, no difference was seen in time to mastery of tasks. In conclusion, treatment with exosomes attenuates the severity of neurologic injury and allows for faster neurologic recovery in a clinically realistic large animal model of TBI and HS.

Histone deacetylase inhibitors: Isoform selectivity improves survival in a hemorrhagic shock model

BACKGROUND

Hemorrhage is a leading preventable cause of death. Nonselective histone deacetylase inhibitors (HDACIs), such as valproic acid (VPA), have been shown to improve outcomes in hemorrhagic shock (HS). The HDACs can be divided into four functional classes (I, IIa/IIb, III, and IV). Classes I, IIa/IIb, and III have previously been implicated in the pathophysiology of HS. This study aimed to determine which HDAC class, or classes, are responsible for the survival benefit observed with nonselective HDACIs.

METHODS

Survival study: Sprague-Dawley rats were subjected to lethal HS (50% hemorrhage) and randomized to the following groups (n = 8): (1) no treatment, (2) normal saline vehicle, (3) cyclodextrin vehicle, (4) MS275 (class I HDACI), (5) VPA (class I/IIa HDACI), (6) MC1568 (class IIa HDACI), (7) ACY1083 (class IIb HDACI), and (8) EX527 (class III HDACI). Survival was monitored for 24 hours. Mechanistic study: Sprague-Dawley rats were subjected to sublethal HS (40% hemorrhage) and randomized to the same groups (n = 3), excluding EX527, based on results of the survival study. Tissues were harvested at 3 hours posttreatment, and expression of phosphorylated-AKT, β-catenin, acetylated histones H3 and H4, and acetylated α-tubulin were analyzed in myocardial tissue.

RESULTS

Survival rate was 12.5% in the untreated group, and did not improve with vehicle or MS275 treatment. EX527 improved survival to 50%, although this did not achieve statistical significance (p = 0.082). However, treatment with VPA, MC1568, and ACY1083 improved survival rates to 87.5%, 75%, and 75%, respectively (p < 0.05). The VPA-induced acetylation of both histones H3 and H4, while MC1568 and ACY1083 increased acetylation of histone H4. ACY1083 also induced acetylation of α-tubulin. All treatment groups, except MS275, increased phosphorylated-AKT, and β-catenin.

CONCLUSION

Inhibition of HDAC classes IIa or IIb, but not class I, activates prosurvival pathways, which may be responsible for the improved outcomes in rodent models of HS.

The role of telemedicine in postoperative care

Telemedicine has become one of the most rapidly-expanding components of the health care system. Its adoption has afforded improved access to care, greater resource efficiency, and decreased costs associated with traditional office visits and has been well established in a wide array of fields. Telemedicine has been adopted in several domains of surgical care. In recent years, the role of telemedicine in postoperative care has caught attention as it has demonstrated excellent clinical outcomes, enhanced patient satisfaction, increased accessibility along with reduced wait times, and cost savings for patients and health care systems. In this narrative review, we describe the history of telemedicine, its adoption in the field of surgery and its various modalities, its use in the postoperative setting, and the potential benefits to both patients and healthcare systems. As telemedicine continues to emerge as a powerful tool for health care delivery, we also discuss several barriers to its widespread adoption as well as the future utility of telemedicine in postoperative care.