Systemic Inflammatory Responses and Lung Injury following Hip Fracture Surgery Increases Susceptibility to Infection in Aged Rats

Abstract

Pulmonary infections frequently occur following hip fracture surgery in aged patients. However, the underlying reasons are not fully understood. The present study investigates the systemic inflammatory response and pulmonary conditions following hip fracture surgery as a means of identifying risk factors for lung infections using an aged rodent model. Aged, male Sprague-Dawley rats (8 animals per group) underwent a sham procedure or hip fracture plus femoral intramedullary pinning. Animals were sacrificed 1, 3, and 7 days after the injury. Markers of systemic inflammation and pulmonary injury were analyzed. Both sham-operated and injured/surgical group animals underwent intratracheal inoculation with Pseudomonas aeruginosa 1, 3, and 7 days after surgery. P. aeruginosa counts in blood and bronchoalveolar lavage (BAL) fluid and survival rates were recorded. Serum TNF-α, IL-6, IL-1β, and IL-10 levels and markers of pulmonary injury were significantly increased at 1 and 3 days following hip fracture and surgery. Animals challenged with P. aeruginosa at 1 and 3 days after injury had a significantly decreased survival rate and more P. aeruginosa recovered from blood and BAL fluid. This study shows that hip fracture and surgery in aged rats induced a systemic inflammatory response and lung injury associated with increased susceptibility to infection during the acute phase after injury and surgery.

The Immediate Intramedullary Nailing Surgery Increased the Mitochondrial DNA Release That Aggravated Systemic Inflammatory Response and Lung Injury Induced by Elderly Hip Fracture

“…Surgical and clinical dogma states that if, at all possible, any patient with a hip fracture should undergo surgical fixation as soon as possible because any delay in surgery is thought to increase the risk of complications and death [ 6 , 7 , 39 , 40 ]. However, hip fracture in the elderly can induce systemic inflammatory responses and lung injury, which increase the risk of pulmonary infection and death during the postinjury period [ 9 – 11 ]. In addition, the DCO proposes that immediate definitive fixation of long-bone fractures can be detrimental to patients who are physiologically unstable [ 12 , 13 ].…”

“…Previous studies have reported that elderly hip fracture induces a systemic inflammatory response and lung injury and increases the incidence of complications and mortality in elderly patients [ 1 , 9 , 11 , 30 , 32 , 35 ]. Any neglect or misdiagnosis of this condition may produce disastrous results.…”

“…Traditionally, long-term bed rest is considered the main risk factor for the development of lung infections and death, and early and ultraearly surgery in hip fracture patients can reduce the postoperative complications and mortality associated with long-term best rest [ 5 – 8 ]. However, our recent studies have demonstrated that hip fracture in the elderly can induce systemic inflammatory responses and lung injury, which increase the risk of pulmonary infection and death during the postinjury period [ 9 – 11 ]. In addition, damage control orthopedics (DCO) findings suggest that immediate definitive fixation of long-bone fractures can be detrimental to patients who are physiologically unstable [ 12 , 13 ].…”

Timing of hip hemiarthroplasty and the influence on prosthetic joint infection

“…Although patients that were operated on within 48 hours from presentation did not seem to have increased risk of PJI with increased pre-operative waiting time, there are several other legitimate reasons to focus on decreasing time to operation for hip fracture patients [19] , [20], [21], [22] , [23]. However, the potential benefits of early surgery must be weighed against the need for time consuming medical optimization of the often medically complicated hip fracture patients.…”

MicroRNA‑146a/Toll‑like receptor 4 signaling protects against severe burn‑induced remote acute lung injury in rats via anti‑inflammation

“…Uncontrollable inflammatory mediators are closely associated with ALI (4). Macrophages were in patients with ALI to induce inflammation (6). In addition, numerous inflammatory cytokines are released, including interleukin (IL)-6, IL-18, tumor necrosis factor-α (TNF-α) and interferon-γ.…”