Surgical interhospital transfer mortality: national analysis.

BACKGROUND: Interhospital transfers of surgical patients are an independent risk factor for mortality. The Australian and New Zealand Audit of Surgical Mortality (ANZASM) aims to improve surgical care through assessment of all cases of surgical mortality. This study aimed to describe common clinical management issues that contributed to interhospital transfer patient mortality. METHODS: Data for all surgical patient mortality in Australia (except New South Wales) that underwent interhospital transfer between 1 January 2010 and 31 December 2019 were extracted from ANZASM. The surgeons' reports and assessors' evaluations were examined to identify clinical management issues. Thematic analysis was performed to develop pertinent themes and subthemes. RESULTS: Some 8679 patients were identified over the 10-year period. Of these, 2171 (25.0 per cent) had 3259 clinical management issues identified. Prominent themes were operative design (n = 466, 14.3 per cent), decision to operate (n = 425, 13.0 per cent), medical conditions (n = 344, 10.6 per cent), diagnosis (n = 326, 10 per cent), transfer (n = 293, 10.0 per cent), intraoperative issues (n = 278, 8.5 per cent), inadequate assessment (n = 238, 7.3 per cent), communication (n = 224, 6.9 per cent), delay in recognizing complications (n = 180, 5.5 per cent), coagulopathy (n = 151, 4.6 per cent), insufficient monitoring (n = 127, 3.9 per cent), infection (n = 107, 3.3 per cent), and hospital resources (n = 100, 3.1 per cent). Assessors considered 58.4 per cent of clinical management issues (n = 1903) probably or definitely preventable. CONCLUSION: This study identified 13 themes of potentially avoidable management issues present in surgical mortality following interhospital transfers. Quality-improvement initiatives targeting these areas may improve surgical patient outcomes.

Emergency Neurosurgery Performed by General Surgeons: A Systematic Review.

BACKGROUND: In under-resourced settings, general surgeons may be called upon to perform emergency operations within other specialties. Accordingly, we aimed to characterise patient outcomes after emergency neurosurgery performed by a general surgeon or general surgery trainee. METHODS: PubMed, Embase and the Cochrane Library were searched to 30 May 2021 for observational studies reporting outcomes after emergency neurosurgery performed by a general surgeon. Study screening, data extraction, and risk of bias using the Downs and Black checklist were performed in duplicate. Data on setting, operation undertaken, mortality rates and complications were extracted. Meta-analysis was planned but not possible due to heterogeneity. This study is registered with PROSPERO, CRD42021258097. RESULTS: From 632 records, 14 retrospective observational studies were included, covering a total sample of 1,988 operations. Four studies were from Australia, and the remaining 10 were, respectively, from 10 other countries. Most common operations performed were decompressive surgery with burr holes or craniectomy for head trauma and insertion of intracranial pressure monitors. Rural hospitals were the most common settings. Mortality rates for procedures performed by general surgeons at latest follow-up were heterogenous, ranging from 5% for evacuation of chronic subdural haematoma in Kenya to 81% in head injured patients in a Hong Kong study. CONCLUSIONS: This is the first systematic review that synthesises the literature to characterise patient outcomes after neurosurgical operations performed by a general surgeon. Findings from this study may benefit global surgery performed in rural, remote, military or humanitarian settings.

Endovascular thrombectomy for large vessel occlusion acute ischemic stroke after cardiac surgery.

INTRODUCTION: Acute ischemic stroke (AIS) can be a catastrophic complication of cardiac surgery previously without effective treatment. Endovascular thrombectomy (EVT) is a potentially life-saving intervention. We examined patients at our institution who had EVT to treat AIS post cardiac surgery. METHODS: We retrospectively reviewed a stroke database from January 1, 2016 to October 31, 2021 to identify patients who had undergone EVT to treat AIS following cardiac surgery. Demographic data, operation type, stroke severity, imaging features, management and outcomes (mortality and modified Rankin Score (mRS)) were assessed. RESULTS: Of 5022 consecutive patients with AIS, 870 underwent EVT. Seven patients (0.8%) had EVT following cardiac surgery. Operations varied: two coronary artery bypass grafting (CABG), two transcatheter AVR, one redo surgical aortic valve replacement (AVR), one mitral valve repair and one patient with combined aortic and mitral valve replacements and CABG. Meantime postsurgery to stroke symptoms onset was 3 days (range 0-9 days). Median NIHSS was 26 (range 10-32). Five patients had middle cerebral artery occlusion and two internal carotid artery (n = 2). Median time between onset of symptoms and recanalization was 157 min (range 97-263). Two patients received Intra-arterial Thrombolysis. All patients survived and were discharged to another hospital (n = 3), home (n = 2), or rehabilitation facility (n = 2). Median 3-month mRS was 3 (range 0-6). CONCLUSION: We report the largest case series of EVT after cardiac surgery. EVT can be associated with excellent outcomes in these patients. Close neurological monitoring postoperatively to identify patients who may benefit from intervention is key.

Efficacy and Safety of Novel Beta-Chitin Patches as Haemostat in Rat Vascular and Neurosurgical Model.

Background: Intraoperative hemorrhage is a major cause of poor post-operative outcome. Beta-chitin patch has previously been found to be an effective haemostat, but whether modifying the patch can improve its efficacy and safety, remains unknown. In this study, beta-chitin patches were modified using polyethylene oxide, Pluronic-F127 (Chi/F127), calcium (Chi/20%Ca), increased thickness (Chi/Thick) or polyphosphate (Chi/PP). Objective: Using rat (Wistar Albino; 8-10 weeks old) vascular and neurosurgical models, this project investigated and compared the efficacy and safety of beta-chitin patches with gauze, Surgicel and FloSeal. Methods: Ninety rats underwent a standardized femoral artery injury and were randomized to receive either beta-chitin patches, gauze, Surgicel or FloSeal. The bleeding time and total blood loss was measured. For the neurosurgical model, forty-four rats underwent a standardized cortical injury and randomization to a treatment group. Following a 48 h recovery period, their brains were collected for histopathological examination. Results: The mean bleeding time with Chitin (120.8 s) and Chi/PP (117.3 s) was ~60 s lower than Chi/F127, Chi/20%Ca and Chi/Thick (p < 0.05). Chitin and Chi/PP had a significantly lower bleeding time than FloSeal (174.2 s) (p < 0.05), but not Surgicel (172.7 s). Gauze (400 s) had a significantly higher bleeding time compared to all other groups (p < 0.05). There were no significant differences in the total blood loss between the groups. Histopathological examination of brains found no adverse inflammatory reaction to any of the haemostatic compounds. Conclusion: Chi/PP had superior haemostatic efficacy compared to Surgicel and FloSeal, but not compared to non-modified beta-chitin patch. All of the haemostats were equally safe.

The potential of chitosan-based haemostats for use in neurosurgical setting - Literature review.

Haemorrhage is a major nuance in neurosurgery since blood can distort the surgeon's field of view and increase the risk of post-operative complications. Currently a variety of commercially available haemostats have been approved for use in neurosurgery, but they have caveats to their use in the brain, including, localised tissue compression, neural toxicity, induce immune reaction or form thrombus within the vessel. Thus, there is a need for haemostats that are efficacious and safe for application on brain and spinal tissue. Chitosan is a naturally occurring bio-polymer that is found on the exoskeleton of arthropods and the cell wall of fungi. Chitosan has been shown to accelerate haemostasis through a myriad of physiological pathways. These findings have led to the development of multiple chitosan-based haemostats, for use in peripheral human tissue. Although, clinical data regarding the use of chitosan-based haemostats in the brain is lacking, a range on in vivo studies have proven chitosan to be efficacious and safe in managing neurosurgical bleeds. Similarly, literature comparing chitosan-based haemostats with commercial haemostats used commonly in neurosurgery, have all demonstrated chitosan to be the superior agent. Additionally, clinical trials of chitosan-based haemostat used in peripheral tissue have all demonstrated chitosan to be safe for human use. The marriage of these findings indicates that the safety and superior efficacy of chitosan-based haemostat, makes it a potentially suitable haemostat for use in neurosurgical setting. However, further research pertaining to the clinical use of chitosan-based haemostat within the central nervous system needs to be conducted.

The effect of chemical and structural modifiers on the haemostatic process and cytotoxicity of the beta-chitin patch.

Beta-chitin patch has previously been proven to be an effective haemostat, but whether modifying the patch affects its efficacy and safety, remains unanswered. In this study, the patch was modified using polyethylene oxide, Pluronic-F127, calcium, increased thickness or polyphosphate, and their effect on the process of haemostasis and cytotoxicity was tested and compared with standard-of-care, Surgicel and FloSeal. Whole blood collected from volunteers was applied to the patches to test their whole blood clotting and thrombin generation capacities, whilst platelet isolates were used to test their platelet aggregation ability. The fluid absorption capacity of the patches was tested using simulated body fluid. Cytotoxicity of the patches was tested using AlamarBlue assays and PC12 cells and the results were compared with the standard-of-care. In this study, beta-chitin patch modifications failed to improve its whole blood clotting, platelet aggregation and thrombin generation capacity. Compared to non-modified patch, modifications with polyethylene oxide or calcium reduced platelet aggregation and thrombin generation capacity, while increasing the thickness or adding polyphosphate decreased platelet aggregation capacity. The cytotoxicity assays demonstrated that the beta-chitin patches were non-toxic to cells. In vivo research is required to evaluate the safety and efficacy of the beta-chitin patches in a clinical setting.

Postoperative headache following treatment of vestibular schwannoma: A literature review.

Vestibular schwannoma (VS) is a brain tumour arising from Schwann cells that is typically closely associated with the vestibulocochlear nerve. Post-operative headaches (POH) are a potentially common complication of surgery for VS. Greatly differing rates of POH have previously been reported, particularly with different surgical approaches. The aim of this review is to identify and summarise the available peer-reviewed evidence on rates of POH following operative (or radiosurgery) treatment for VS, in addition to information about the treatment and prognosis of POH in these patients. A systematic search was conducted of Pubmed, Medline, Scopus and EMBASE in April 2017 using the medical subject headings (acoustic neuroma OR vestibular schwannoma) AND headache. Eligibility determination and data extraction were performed in duplicate with standardised forms. POH is common following surgery for VS. Differing rates of POH have been reported with different management approaches, patient age and tumour size. There are relatively few studies that have directly compared the rates of POH with different surgical approaches. The retrosigmoid approach with craniotomy appears to have lower rates of POH than when the retrosigmoid approach is performed with craniectomy. Patients under the age of 65 and with tumours <1.5 cm in size appear to have a higher risk of POH. The most commonly documented management of POH involves simple analgesia, although the majority of patients report this treatment is of only minimal benefit. Further prospective studies comparing rates of POH following different surgical approaches and radiosurgery are required.