Advanced age exacerbates intestinal epithelial permeability after burn injury in mice.

BACKGROUND: Advanced age is an independent risk factor for morbidity and mortality after burn injury. Following burn, the intestines can become permeable leading to the leakage of bacteria and their products from the lumen of the ileum to the portal and systemic circulation. Here, we sought to determine the effects of advanced age on intestinal permeability post burn injury and assess intestinal inflammatory biomarkers. METHODS: Young (4-5 months) and aged (18-22 months) female BALB/cBy mice were subjected to a 12-15% total body surface area (TBSA) sham or burn injury. 24 h after injury, mice were euthanized, and organs collected. Colony-forming units (CFU) were counted from plated mesenteric lymph nodes (MLN). Gene expression of ileal tight junctional proteins, occludin and zonula occludens 1 (ZO-1), in addition to ileal damage associated molecular pattern (DAMP) proteins, S100A8 and S100A9, as well as ileal inflammatory markers IL-6 and TNF-α were measured by qPCR. Intestinal cell death was measured by ELISA. Intestinal permeability was determined by FITC fluorescence in serum; 4kD FITC-dextran was given by oral gavage 3 h before euthanasia. RESULTS: Aged mice subjected to burn injury had increased intestinal permeability as evidenced by a 5.8-fold higher level of FITC-dextran in their serum when compared to all other groups (p < 0.05). In addition, aged burn-injured mice exhibited heightened bacterial accumulation in the MLN with a 15.5-fold increase over all other groups (p < 0.05). Histology of ileum failed to show differences in villus length among all groups. Analysis of ileal tight junctional proteins and inflammatory marker gene expression revealed no difference in Ocln, Tjp1, Il6, or Tnf expression among all groups, but 2.3 and 2.9-fold upregulation of S100a8 and S100a9, respectively, in aged burn-injured mice relative to both young groups and aged sham-injured mice (p < 0.05). Lastly, cell death in the ileum was elevated more than two-fold in aged burn-injured mice relative to young animals regardless of injury (p < 0.05). CONCLUSIONS: These data demonstrate that advanced age exacerbates intestinal epithelial permeability after burn injury. Heightened apoptosis may be responsible for the elevated intestinal leakiness and accumulation of bacteria in mesenteric lymph nodes. In addition, S100a8/9 may serve as a biomarker of elevated inflammation within the intestine.

Comparison of a novel preperitoneal sublay repair with traditional onlay repair of morgagni hernia: a tale of two techniques.

Morgagni hernia (MH) is a rare diaphragmatic hernia which needs surgical repair. The conventional reconstruction involves reduction of hernia, closure of the defect and placement of an intraperitoneal onlay mesh often using robotic platform for ease of dissection and suturing the mesh (r-IPOM). We propose a novel robotic preperitoneal repair (r-TAPP) of MH in four cases and compare them with conventional r-IPOM technique. Between August 2017 and August 2020 nine patients underwent repair of MH. Five cases underwent repair by r-IPOM (group I). For the other four cases, r-TAPP was used (group II). Among the nine cases, the mean age was 53 years in group I and 55 years in group II, mean defect size was 33 mm in group I and 55 mm in group II. Operative time was longer in group II compared to group I (220 min vs 135 min, p = 0.022). Mean length of hospital stay was 1.3 days in group I compared to group II (4.5 and 4.5 vs 1.3 days, p = 0.03). There was statistically significant difference in reduced post-operative pain and time to return to work in group II compared to group I. There was no difference in complications, 30-day readmissions or recurrence of hernia between the two groups. We conclude that compared to the conventional r-IPOM repair, the r-TAPP technique is associated with less pain, early discharge, and faster return to work, translating into overall cost savings for the hospital.

A novel technique of robotic preperitoneal approach for Morgagni hernia repair.

INTRODUCTION: Morgagni hernia (MH) is a rare, congenital diaphragmatic hernia. We developed a novel robotic-assisted technique to repair MH which enables dissection into the preperitoneal space, facilitating closure of the diaphragmatic defect and placement of a synthetic mesh. MATERIALS AND SURGICAL TECHNIQUE: Between August 2017 and August 2020, 8 consecutive patients with MH were repaired by robotic-assisted transabdominal preperitoneal (r-TAPP) approach. A preperitoneal plane is developed at the level of the falciform ligament and extended toward the diaphragmatic defect. The pocket is dissected inferior to the defect to allow 3 to 5 cm overlap of synthetic mesh. Excision of the hernia sac followed by closure of defect is performed. A synthetic mesh is deployed in the preperitoneal space with wide overlap. This technique using the robot provides superior optics and ergonomics for dissection while isolating the mesh from underlying viscera and avoiding the need for suturing or tacking of the mesh. Data of patients who underwent r-TAPP were reviewed. Mean operating time was 113 minutes. Mean pain visual analog scale score was 5/2 on post-operative days 1/7. Average hospital stay was 1.8 days. One patient developed superficial cellulitis related to the abdominal drain. There were no procedure-related complications, 30-day readmissions, or hernia recurrences at a mean follow-up of 10 months. DISCUSSION: A robotic-assisted preperitoneal approach is a novel, safe, and anatomically justified alternative technique for MH repair that may lead to improved post-operative outcomes.

Age-related immune responses after burn and inhalation injury are associated with altered clinical outcomes.

This prospective study aimed to address changes in inflammatory response between different aged populations of patients who sustained burn and inhalation injury. Plasma and bronchoalveolar lavage (BAL) samples were collected from 104 patients within 15h of their estimated time of burn injury. Clinical variables, laboratory parameters, and immune mediator profiles were examined in association with clinical outcomes. Older patients were at higher odds for death after burn injury (odds ratio (OR)=7.37 per 10years, p=0.004). In plasma collected within 15h after burn injury, significant increases in the concentrations of interleukin 1 receptor antagonist (IL-1RA), interleukin 2 (IL-2), interleukin 4 (IL-4), interleukin 6 (IL-6), granulocyte colony-stimulating factor (G-CSF), interferon-gamma-induced protein 10 (IP-10) and monocyte chemoattractant protein 1 (MCP-1) (p<0.05 for all) were observed in the ≥65 group. In the BAL fluid, MCP-1 was increased three-fold in the ≥65 group. This study suggests that changes in certain immune mediators were present in the older cohort, in association with in-hospital mortality.