Recent evidence from case reports suggests that a ketogenic diet may be effective for bipolar disorder. However, no clinical trials have been conducted to date.

To assess the recruitment and feasibility of a ketogenic diet intervention in bipolar disorder.

Euthymic individuals with bipolar disorder were recruited to a 6–8 week trial of a modified ketogenic diet, and a range of clinical, economic and functional outcome measures were assessed. Study registration number: ISRCTN61613198.

Of 27 recruited participants, 26 commenced and 20 completed the modified ketogenic diet for 6–8 weeks. The outcomes data-set was 95% complete for daily ketone measures, 95% complete for daily glucose measures and 95% complete for daily ecological momentary assessment of symptoms during the intervention period. Mean daily blood ketone readings were 1.3 mmol/L (s.d. = 0.77, median = 1.1) during the intervention period, and 91% of all readings indicated ketosis, suggesting a high degree of adherence to the diet. Over 91% of daily blood glucose readings were within normal range, with 9% indicating mild hypoglycaemia. Eleven minor adverse events were recorded, including fatigue, constipation, drowsiness and hunger. One serious adverse event was reported (euglycemic ketoacidosis in a participant taking SGLT2-inhibitor medication).

The recruitment and retention of euthymic individuals with bipolar disorder to a 6–8 week ketogenic diet intervention was feasible, with high completion rates for outcome measures. The majority of participants reached and maintained ketosis, and adverse events were generally mild and modifiable. A future randomised controlled trial is now warranted.

Learning from rewarded and punished choices is perturbed in depressed patients, suggesting that abnormal reinforcement learning may be a cognitive mechanism of the illness. However, previous studies have disagreed about whether this behavior is produced by alterations in the rate of learning or sensitivity to experienced outcomes. This previous work has generally assessed learning in response to binary outcomes of one valence, rather than to both rewarding and punishing continuous outcomes.

A novel drifting reward and punishment magnitude reinforcement-learning task was administered to patients with current (n = 40) and remitted depression (n = 39), and healthy volunteers (n = 40) to capture potential differences in learning behavior. Standard questionnaires were administered to measure self-reported depressive symptom severity, trait and state anxiety and level of anhedonic symptoms.

Our findings demonstrate that patients with current depression adjust their learning behaviors to a lesser degree in response to trial-by-trial variations in reward and loss magnitudes than the other groups. Computational modeling revealed that this behavioral signature of current depressive state is better accounted for by reduced reward and punishment sensitivity (all p < 0.031), rather than a change in learning rate (p = 0.708). However, between-group differences were not related to self-reported symptom severity or comorbid anxiety disorders in the current depression group.

These findings suggest that current depression is associated with reduced outcome sensitivity rather than altered learning rate. Previous findings reported in this domain mainly from binary learning tasks seem to generalize to learning from continuous outcomes.

The National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) lacks a rigorous enrollment audit process, unlike other collaborative networks. Most centers require individual families to consent to participate. It is unknown whether there is variation across centers or biases in enrollment.

We used the Pediatric Cardiac Critical Care Consortium (PC4) registry to assess enrollment rates in NPC-QIC for those centers participating in both registries using indirect identifiers (date of birth, date of admission, gender, and center) to match patient records. All infants born 1/1/2018–12/31/2020 and admitted 30 days of life were eligible. In PC4, all infants with a fundamental diagnosis of hypoplastic left heart or variant or who underwent a surgical or hybrid Norwood or variant were eligible. Standard descriptive statistics were used to describe the cohort and center match rates were plotted on a funnel chart.

Of 898 eligible NPC-QIC patients, 841 were linked to 1,114 eligible PC4 patients (match rate 75.5%) in 32 centers. Match rates were lower in patients of Hispanic/Latino ethnicity (66.1%, p = 0.005), and those with any specified chromosomal abnormality (57.4%, p = 0.002), noncardiac abnormality (67.8%, p = 0.005), or any specified syndrome (66.5%, p = 0.001). Match rates were lower for patients who transferred to another hospital or died prior to discharge. Match rates varied from 0 to 100% across centers.

It is feasible to match patients between the NPC-QIC and PC4 registries. Variation in match rates suggests opportunities for improvement in NPC-QIC patient enrollment.

Patients with Fontan physiology require non-cardiac surgery. Our objectives were to characterise perioperative outcomes of patients with Fontan physiology undergoing non-cardiac surgery and to identify characteristics which predict discharge on the same day.

Children and young adults with Fontan physiology who underwent a non-cardiac surgery or an imaging study under anaesthesia between 2013 and 2019 at a single-centre academic children’s hospital were reviewed in a retrospective observational study. Continuous variables were compared using the Wilcoxon rank sum test, and categorical variables were analysed using the Chi-square test or Fisher’s exact test. Multivariable logistic regression analysis results are presented by adjusted odds ratios with 95% confidence intervals and p values.

182 patients underwent 344 non-cardiac procedures with anaesthesia. The median age was 11 years (IQR 5.2–18), 56.4% were male. General anaesthesia was administered in 289 (84%). 125 patients (36.3%) were discharged on the same day. On multivariable analysis, independent predictors that reduced the odds of same-day discharge included the chronic condition index (OR 0.91 per additional chronic condition, 95% CI 0.76–0.98, p = 0.022), undergoing a major surgical procedure (OR 0.17, 95% CI 0.05–0.64, p = 0.009), the use of intraoperative inotropes (OR 0.48, 95% CI 0.25–0.94, p = 0.031), and preoperative admission (OR = 0.24, 95% CI: 0.1–0.57, p = 0.001).

In a contemporary cohort of paediatric and young adults with Fontan physiology, 36.3% were able to be discharged on the same day of their non-cardiac procedure. Well selected patients with Fontan physiology can undergo anaesthesia without complications and be discharged same day.