Journal update monthly top five

Diagnostic yield of CT imaging and point-of-care ultrasound after in-hospital cardiac arrest by Andrea et al

Topic: Cardiac arrest

Outcome Rating: Worth a peek

Identifying and treating the underlying cause of in-hospital cardiac arrest (IHCA) after return of spontaneous circulation (ROSC) is a cornerstone of post-resuscitation care. While early CT imaging and point-of-care ultrasound (POCUS) are recommended after cardiac arrest, most supporting evidence comes from out-of-hospital populations.¹

This US-based, multicentre, retrospective observational study reviewed 345 adult inpatients who achieved ROSC across two 12-month windows. Prehospital arrests, recurrent arrests and those with ‘Do-Not-Resuscitate’ orders were excluded. The CT imaging arm excluded patients who died within 24 hours of ROSC due to presumed instability and reduced likelihood of CT transfer. There was no protocolisation of the type of CT or POCUS imaging, with the scan region at clinicians’ discretion.

47.7% (112) underwent CT imaging and 76.5% (264) underwent bedside POCUS, with crossover of the cohort between the two arms. Combined CT imaging identified new findings in 65.2% of cases; 65.8% of these new findings led to changes in management. Chest CT had the greatest diagnostic yield, identifying new pathology in 92.2% of scans and prompting management changes in 64.1%. Only one adverse event (cardiac arrest) occurred during CT transfer. In the POCUS arm, new findings were identified in 57.6%, with resulting management changes in 41.3%. Both modalities identified a suspected cause of arrest in approximately one-fifth of patients.

The study’s retrospective design, reliance on clinical documentation and lack of imaging protocolisation introduce potential biases and confounders. The primary outcome of resultant changes in management, rather than a patient-centred one (eg, survival), means the clinical impact remains uncertain.

Bottom line: Early CT and POCUS frequently identify actionable pathology after IHCA but whether this translates into improved patient outcomes remains unknown.

Nebulized heparin in adults with acute respiratory failure: a meta-analysis of randomized trials by Fresilli et al

Topic: Acute respiratory failure

Outcome rating: Head turner

The pathophysiology of acute respiratory failure involves dysregulated pulmonary coagulation and inflammation. Previous trials have demonstrated that nebulised heparin can reduce pulmonary coagulopathy without the side effects of systemic heparin.^{2 3}

This meta-analysis of 16 trials evaluated unfractionated heparin (n=787) versus placebo or standard care (n=833) in acute respiratory failure of various aetiologies. For 10 studies, nebulised heparin reduced the primary outcome of all-cause mortality versus control (risk ratio (RR) 0.79, 95% CI 0.66 to 0.95). However, further analysis to detect and adjust for potential publication bias weakened the RR to 0.83 (95% CI 0.68 to 1.01, p=0.07); certainty of evidence was low.

Ventilator-free days were increased at 28 days (mean difference (MD) + 4.85 days, 95% CI 1.47 to 8.24; moderate certainty of evidence), but without significant improvement in duration of mechanical ventilation (MD −1.39 days, 95% CI −3.46 to 0.68), ICU stay (MD −1.27 days, 95% CI −3.52 to 0.98) or hospital stay (MD −2.18 days, 95% CI −5.63 to 1.28) with a very low certainty of evidence. Subgroup analysis suggested greater benefits in non-ICU patients, patients not mechanically ventilated, and COVID-19 patients. Major bleeding was rare (six vs four patients in nebulised heparin group vs control) and not significantly increased. No cases of minor bleeding or heparin-induced thrombocytopenia were reported.

Clear limitations include publication bias, heterogeneity in heparin dose and delivery, and inclusion of several single-centre studies.

Bottom line: Nebulised heparin appears to be a promising therapy, but it is yet to be established as a standard of care, pending further high-quality randomised trials.

Plasma sodium as a predictor of perforation in acute appendicitis: a prospective multi-centre study by Lindestam et al

Topic: Acute appendicitis

Outcome Rating: Worth a peek

Accurate perioperative differentiation between perforated and non-perforated acute appendicitis (AA) is important, especially given the increase in conservative management in paediatric AA. Lindestam et al previously showed that median plasma sodium (P-Na) was lower in children with perforated AA.^{4 5} This prospective multi-centre study aimed to further investigate characteristics of plasma sodium as a marker of perforation status in paediatric AA presentations.

The study cohort included 451 children (aged 1–15 years) with suspected AA, who underwent appendicectomy across five paediatric surgical centres in Europe and South Africa. Within the cohort, 48.6% had perforated appendicitis.

Mean plasma sodium concentration on admission was significantly lower in children with perforated AA (133.6 vs 138.2 mmol/L). Receiver operating characteristic curve analysis found continuous P-Na, as a predictor of perforation, had an area under the curve of 0.82. A cut-off value of P-Na ≦ 136 mmol/L had the best sensitivity (0.76) and specificity (0.75) and resulted in an OR of 0.11 (95% CI 0.07 to 0.17) when compared with >136 mmol/L. CRP and P-Na were the only statistically significant predictors within a multivariate logistic regression model, with ORs of 7.27 (95% CI 4.46 to 12) and 0.22 (95% CI 0.13 to 0.36), respectively. Combining P-Na and CRP produced a modest but statistically significant improvement in discrimination, increasing AUC from 0.82 to 0.86 (p<0.001).

This study supports low P-Na as an associated marker for perforation in AA. However, diagnostic discrimination does not translate to an individual’s absolute risk of perforation. The differing disease severity and perforation rates between centres may limit generalisability of cut-offs and estimates.

Bottom line: Low plasma sodium, particularly when interpreted alongside C-reactive protein, is a potential predictor of perforation, but evidence is insufficient to establish it as a clinically useful risk-stratification tool.

Risk of presentation for sexual abuse after a first emergency department presentation for self-harm in childhood or adolescence by Blundell et al

Topic: Paediatric mental health

Outcome rating: Worth a peek

Children and young people presenting to the emergency department (ED) with self-harm are recognised as a high-risk group but less is known about their subsequent vulnerability to sexual abuse. Blundell et al conducted a population-based cohort study in Ontario, Canada, linking healthcare records to compare >26 000 children and adolescents presenting to the ED with a first episode of self-harm with 112 000 matched controls. Subsequent healthcare presentations for sexual abuse or assault were examined over a 10-year period.⁶

Blundell et al confirmed a strong relationship between sexual abuse presentation and self-harm presentations (aOR 5.29, CI 4.65 to 5.99). They also found that first ED presentation with self-harm was associated with a substantially increased cumulative incidence (9.06%, 95% CI 8.55 to 9.57) of later presentation for both sexual abuse and assault compared with controls (1.26%, 95% CI 1.17 to 1.36). This difference remained after adjusting for previous presentations of abuse, prior mental health service use, and sociodemographic factors; fully adjusted HR 5.06 (95% CI 4.53 to 5.65). While females had the highest cumulative incidence (1.33%) and strongest association for subsequent sexual abuse (HR 8.40, 95% CI 6.38 to 11.08), the association was observed across sexes. Importantly, most patients who later presented with sexual abuse had no documented prior abuse before their self-harm presentation, suggesting self-harm may act as an early marker of unrecognised vulnerability for future sexual abuse or assault.

The strong methodology is limited by its reliance on routinely collected healthcare data, meaning only abuse resulting in healthcare contact was captured, likely underestimating the true burden and preferentially identifying more severe cases. Residual confounding and incomplete demographic and psychosocial data limit causal interpretation. Nevertheless, the findings reinforce the ED’s role in trauma-informed assessment, early safeguarding and follow-up.

Bottom line: A first ED presentation with self-harm in childhood or adolescence should prompt consideration of both previous abuse and future vulnerability, with ongoing safeguarding needs.

A systematic review on the role of high-dose vitamin C in trauma patients by Patel et al

Topic: Trauma

Outcome rating: Worth a peek

Following initial resuscitation in major trauma, vitamin C stores are rapidly depleted through multiple physiological pathways associated with the stress response. Use of vitamin C in other critical care settings has been studied with variable findings.⁷

This systematic review evaluated the role of vitamin C in adults with traumatic injuries. Six studies of 5171 patients were included. These were published between 2002 and 2021 and comprised three randomised controlled trials and three cohort studies. The primary outcome was 30-day mortality. Secondary outcomes included physiological scoring, incidence of complications, and length of stay. Meta-analysis was not possible due to variability between studies.

The potential benefit of vitamin C in the trauma population was supported by several statistically significant findings: four studies identified a reduction in mortality; one found shorter ICU stays; one found higher rates of ICU and 28-day hospital discharge; two identified reduced hospital stays; two found reduction in sepsis; and one specifically during the first 7 days. Both studies reporting incidence of multi-organ failure/dysfunction found a significant reduction. None found evidence of harm.

Of the six studies, most had a small sample size (median 76). GRADE assessment rated certainty of evidence as low to very low across all outcomes. No studies assessed vitamin C monotherapy; hence, effects cannot be isolated. There was significant heterogeneity in methodology, dosing and outcome reporting. The results, while not contradictory, showed variability.

Bottom line: Vitamin C administration in major trauma shows some positive outcomes, further research reviewing dosage, timing and different trauma presentations that are required to improve confidence in results.