Free flap reconstruction following head and neck trauma.

BACKGROUND: Free flap (FF) reconstruction of traumatic injuries to the head and neck is uncommon. METHODS: Multi-institutional retrospective case series of patients undergoing FF reconstruction for a traumatic injury (n = 103). RESULTS: Majority were gunshot wounds (GSW; 85%, n = 88) and motor vehicle accidents (11%, n = 11). Majority underwent osseous reconstruction (82%, n = 84). FF failures (9%, n = 9/103) occurred in GSW patients (100%, n = 9/9) and when multiple subsites were injured (89%, n = 8/9). Preoperative antibiotics correlated with lower rates of a neck washouts (4% vs. 19%) (p = 0.01) and 30-day readmissions (4% vs. 17%) (p = 0.02). CONCLUSIONS: All FF failures occurred in the setting of a GSW and the majority involved multiple subsites. Preoperative antibiotics correlated with lower rates of postoperative washout procedures and 30-day readmission.

Moving to a more restrictive transfusion protocol: Outcomes in head and neck free flap surgery.

PURPOSE: To determine if a more restrictive transfusion protocol results in increased rates of adverse flap outcomes in patients undergoing free tissue transfer. MATERIALS AND METHODS: Mixed retrospective and prospective cohort study. Patients who underwent surgery before the protocol change were collected retrospectively. Patients who underwent surgery after the protocol change were collected prospectively. RESULTS: Of the 460 patients who underwent free tissue transfer, 116 patients in the pre-change cohort (N = 211) underwent transfusion (54.98%) and 78 in the post-change cohort(N = 249) (31.33%) (p < 0.001). The mean number of units transfused was 1.55 + 2.00 in the pre-change cohort, and 0.78 + 1.51 in the post-change cohort (p < 0.001). When separated temporally, the pre-change cohort received significantly more blood transfusions than the post-change cohort in the operating room (33.65% vs 18.07%) (p < 0.01), within 72 h of surgery (35.55% vs 15.66%) (p < 0.001), and after 72 h after surgery to discharge (16.59% vs 8.03%) (p = 0.018017). The rate of flap failure was 6.70% in the pre-change cohort, and 5.31% in the post-change cohort (p = 0.67). In a logistic regression model controlling for potential confounders, transfusion protocol was not significantly associated with flap failure (OR = 1.1080, 95% CI: 0.48-2.54). There were no significant differences between cohorts for medical morbidity, ICU transfer, or death. CONCLUSION: Our data support the conclusion that patients undergoing free tissue transfer to the head and neck can be transfused following the same protocols as other patients, without increasing the rate of flap failure or other morbidities. LEVEL OF EVIDENCE: 3 (mixed retrospective, prospective cohort study).

Tracheotomy in the SARS-CoV-2 pandemic.

The severe acute respiratory syndrome (SARS)-CoV-2 pandemic continues to produce a large number of patients with chronic respiratory failure and ventilator dependence. As such, surgeons will be called upon to perform tracheotomy for a subset of these chronically intubated patients. As seen during the SARS and the SARS-CoV-2 outbreaks, aerosol-generating procedures (AGP) have been associated with higher rates of infection of medical personnel and potential acceleration of viral dissemination throughout the medical center. Therefore, a thoughtful approach to tracheotomy (and other AGPs) is imperative and maintaining traditional management norms may be unsuitable or even potentially harmful. We sought to review the existing evidence informing best practices and then develop straightforward guidelines for tracheotomy during the SARS-CoV-2 pandemic. This communication is the product of those efforts and is based on national and international experience with the current SARS-CoV-2 pandemic and the SARS epidemic of 2002/2003.

Submandibular neck mass in a newborn.

A deep neck abscess is uncommon in the newborn period. In this case, we noted a clindamycin-sensitive methicillin-resistant Staphylococcus aureus infection characterized as a deep neck abscess in an 8-day-old boy. He was admitted to the pediatric intensive care unit with a progressively enlarging indurated mass below the mandible. Imaging confirmed the mass as a submandibular abscess. The patient received antibiotics in addition to incision and drainage, with resolution of the abscess.

Mast cells and histamine are triggering the NF-κB-mediated reactions of adult and aged perilymphatic mesenteric tissues to acute inflammation.

This study aimed to establish mechanistic links between the aging-associated changes in the functional status of mast cells and the altered responses of mesenteric tissue and mesenteric lymphatic vessels (MLVs) to acute inflammation. We used an in vivo model of acute peritoneal inflammation induced by lipopolysaccharide treatment of adult (9-month) and aged (24-month) F-344 rats. We analyzed contractility of isolated MLVs, mast cell activation, activation of nuclear factor-κB (NF-κB) without and with stabilization of mast cells by cromolyn or blockade of all types of histamine receptors and production of 27 major pro-inflammatory cytokines in adult and aged perilymphatic mesenteric tissues and blood. We found that the reactivity of aged contracting lymphatic vessels to LPS-induced acute inflammation was abolished and that activated mast cells trigger NF-κB signaling in the mesentery through release of histamine. The aging-associated basal activation of mesenteric mast cells limits acute inflammatory NF-κB activation in aged mesentery. We conclude that proper functioning of the mast cell/histamine/NF-κB axis is necessary for reactions of the lymphatic vessels to acute inflammatory stimuli as well as for interaction and trafficking of immune cells near and within the collecting lymphatics.

Reticulation of low density shape memory polymer foam with an in vivo demonstration of vascular occlusion.

Predominantly closed-cell low density shape memory polymer (SMP) foam was recently reported to be an effective aneurysm filling device in a porcine model (Rodriguez et al., Journal of Biomedical Materials Research Part A 2013: (http://dx.doi.org/10.1002/jbm.a.34782)). Because healing involves blood clotting and cell migration throughout the foam volume, a more open-cell structure may further enhance the healing response. This research sought to develop a non-destructive reticulation process for this SMP foam to disrupt the membranes between pore cells. Non-destructive mechanical reticulation was achieved using a gravity-driven floating nitinol pin array coupled with vibratory agitation of the foam and supplemental chemical etching. Reticulation resulted in a reduced elastic modulus and increased permeability, but did not impede the shape memory behavior. Reticulated foams were capable of achieving rapid vascular occlusion in an in vivo porcine model.