Evaluating temporal trends and the impact of surgical subspecialisation on patient outcomes following adhesional small bowel obstruction: a multicentre cohort study.

PURPOSE: Small bowel obstruction (SBO) is the most common indication for laparotomy in the UK. While general surgeons have become increasingly subspecialised in their elective practice, emergency admissions commonly remain undifferentiated. This study aimed to assess temporal trends in the management of adhesional SBO and explore the influence of subspecialisation on patient outcomes. METHODS: Data was collected for patients admitted acutely with adhesional SBO across acute NHS trusts in Northern England between 01/01/02 and 31/12/16, including demographics, co-morbidities and procedures performed. Patients were excluded if a potentially non-adhesional cause was identified and were grouped by the responsible consultant's subspecialty. The primary outcome of interest was 30-day inpatient mortality. RESULTS: Overall, 2818 patients were admitted with adhesional SBO during a 15-year period. There was a consistent female preponderance, but age and comorbidity increased significantly over time (both p < 0.001). In recent years, more patients were managed operatively with a trend away from delayed surgery also evident (2002-2006: 65.7% vs. 2012-2016: 42.7%, p < 0.001). Delayed surgery was associated with an increased mortality risk on multivariable regression analysis (OR: 2.46 (1.46-4.23, p = 0.001)). CT scanning was not associated with management strategy or timing of surgery (p = 0.369). There was an increased propensity for patients to be managed by gastrointestinal (colorectal and upper gastrointestinal) subspecialists over time. Length of stay (p < 0.001) and 30-day mortality (p < 0.001) both improved in recent years, with the best outcomes seen in colorectal (2.6%) and vascular subspecialists (2.4%). However, following adjustment for confounding variables, consultant subspecialty was not a predictor of mortality. CONCLUSION: Outcomes for patients presenting with adhesional SBO have improved despite the increasing burden of age and co-morbidity. While gastrointestinal subspecialists are increasingly responsible for their care, mortality is not influenced by consultant subspecialty.

Near-infrared spectroscopy (NIRS) measured tissue oxygenation in neonates with gastroschisis: a pilot study.

BACKGROUND: Management of gastroschisis involves either primary or staged closure. Bowel ischemia and abdominal compartment syndrome (ACS) are possible complications that can be related to a method of treatment. NIRS monitoring has never been applied in this group of patients and may allow for earlier detection of complications. OBJECTIVE: To assess near-infrared spectroscopy (NIRS) monitoring in neonates with gastroschisis for detecting changes in tissue oxygenation (rSO2) related to bowel reductions or height of bowel in the silo and for detecting tissue ischemia. METHODS: Patients with gastroschisis and controls underwent continuous multi-channel assessment of oxygenation of the brain (CrSO2), kidney (RrSO2) and bowel (GrSO2) in a prospective pilot study. RESULTS: Fifteen neonates were treated with primary closure (n = 3) or staged closure (n = 12); two had confirmed bowel ischemia, none developed ACS.There was no significant correlation between height of the bowel and GrSO2 at apex (p = .72) or base (p = .54) within the silo. During staged reductions there was a clinically non-significant change in RrSO2 (Δ-2.5%, p = .04), but no significant changes in CrSO2 (p = .11), and GrSO2 of apex (p = .97) and base (p = .31). Patients with confirmed ischemia had GrSO2 that were lower than controls. CONCLUSIONS: Measuring GrSO2 through a silo is feasible. Staged reduction seems safe based on NIRS measurements, with minimal effect of hydrostatic pressure on bowel oxygenation. NIRS was able to detect subtle changes in intra-abdominal renal perfusion during reduction and could differentiate healthy and ischemic bowel.

NIRS as a biomarker of bowel ischaemia & surgical pathology: A meta-analysis of studies in newborns.

OBJECTIVE: We performed a meta-analysis on Near-infrared Spectroscopy (NIRS) as a biomarker of bowel ischaemia. SUMMARY BACKGROUND DATA: NIRS allows non-invasive assessment of gastrointestinal regional oxygen saturation (GrSO2). Studies to date have focused on the feasibility of NIRS in clinical practice and its reproducibility. GrSO2 can be used alone, or in conjunction with cerebral NIRS to give a Cerebral Splanchnic Oxygenation Ratio (CSOR). We assess published data on abdominal NIRS as a marker of bowel ischaemia. METHODS: A literature review was conducted using the PRISMA method. Data on GrSO2 and CSOR in controls and patients with confirmed ischaemia was included in a meta-analysis, and used to identify a diagnostic threshold. RESULTS: 14 studies were identified. Meta-analysis demonstrated that GrSO2 (p < 0.01) and CSOR (p < 0.01) were significantly lower in neonates with bowel pathology associated with ischaemia than controls. Area under the curve for GrSO2 was 0.80, with Youden's index highest (0.52) at a GrSO2 of 42% (specificity 91% and sensitivity 62%). For CSOR, area under the curve is 0.89, with Youden's index highest (0.69) at 0.76 (specificity of 80%, sensitivity 90%). CONCLUSIONS: Splanchnic NIRS correlates with bowel ischaemia. Low GrSO2 is consistently associated with ischaemia, although a specific cut off level in each patient is hard to define. However, values below 42% correlate strongly with ischaemia while values above 52% are more suggestive of patients without bowel pathology. CSOR of below 0.76 is strongly suggestive of ischaemia. Trends within individuals are likely to be able to provide even more clinically correlatable and diagnostic data.