Characteristics and outcomes for general anesthesia in Denmark.

BACKGROUND: General anesthesia is common, but concerns regarding post-operative complications and mortality remain. No study has described the Danish patient population undergoing general anesthesia on a national level. The aim of this study was to describe the characteristics and outcomes of patients undergoing general anesthesia in Denmark. METHODS: This study was a registry-based observational cohort study of adult patients (≥18 years) undergoing general anesthesia in Denmark during 2020 and 2021. Data from nationwide registries covering patient characteristics, anesthesia and procedure information, and patient outcomes were combined. Descriptive statistics were used to present findings, both overall and in subgroups based on the American Society of Anesthesiologists (ASA) classification. RESULTS: We identified 453,133 cases of general anesthesia in 328,951 unique patients. The median age was 57 years (quartiles: 41, 71), and 242,679 (54%) were females. Data on ASA classification were missing for less than 1% of the population, and ASA II was the most prevalent ASA classification (49%). Among cases of general anesthesia, 0.1% experienced a stroke, 0.2% had in-hospital cardiac arrest, and 3.9% had a stay in the intensive care unit within 30 days. Mortality at 30 days and 1 year were 1.8% and 6.3%, respectively, increasing with a higher ASA classification. CONCLUSION: This study offers the first comprehensive overview of adult patients undergoing general anesthesia in Denmark. Post-anesthesia complications were few and increased with ASA classification.

The effects of methylene blue during and after cardiac arrest in a porcine model; a randomized, blinded, placebo-controlled study.

PURPOSE: To evaluate the effect of methylene blue administered as a bolus on return of spontaneous circulation (ROSC), lactate levels, vasopressor requirements, and markers of neurological injury in a clinically relevant pig model of cardiac arrest. MATERIALS AND METHODS: 40 anesthetized pigs were subjected to acute myocardial infarction and 7 min of untreated cardiac arrest. Animals were randomized into three groups: one group received saline only (controls), one group received 2 mg/kg methylene blue and saline (MB + saline), and one group received two doses of 2 mg/kg methylene blue (MB + MB). The first intervention was given after the 3rd rhythm analysis, while the second dose was administered one hour after achieving ROSC. Animals underwent intensive care and observation for six hours, followed by cerebral magnetic resonance imaging (MRI). The primary outcome for this study was development in lactate levels after cardiac arrest. Categorical data were compared using Fisher's exact test and pointwise data were analyzed using one-way analysis of variance (ANOVA) or equivalent non-parametric test. Continuous data collected over time were analyzed using a linear mixed effects model. A value of p < .05 was considered statistically significant. RESULTS: Lactate levels increased in all groups after cardiac arrest and resuscitation, however lactate levels in the MB + MB group decreased significantly faster compared with the control group (p = .007) and the MB + saline group (p = .02). The proportion of animals achieving initial ROSC was similar across groups: 11/13 (85%) in the control group, 10/13 (77%) in the MB + saline group, and 12/14 (86%) in the MB + MB group (p = .81). Time to ROSC did not differ between groups (p = .67). There was no significant difference in accumulated norepinephrine dose between groups (p = .15). Cerebral glycerol levels were significantly lower in the MB + MB group after resuscitation compared with control group (p = .03). However, MRI data revealed no difference in apparent diffusion coefficient, cerebral blood flow, or dynamic contrast enhanced MR perfusion between groups. CONCLUSION: Treatment with a bolus of methylene blue during cardiac arrest and after resuscitation did not significantly improve hemodynamic function. A bolus of methylene blue did not yield the neuroprotective effects that have previously been described in animals receiving methylene blue as an infusion.

Lack of an association between first-trimester concentration of mid-regional pro-atrial natriuretic peptide and risk of early-onset preeclampsia <34 weeks' gestation.

AIM: We examined the heart failure biomarker mid-regional pro-atrial natriuretic peptide during the first trimester of pregnancy in relation to early-onset preeclampsia <34 weeks. MATERIALS AND METHODS: This case-control study included 34 women with singleton pregnancies with a preeclampsia diagnosis and delivery before 34 weeks of gestation who had attended the routine first-trimester ultrasound scan at 11-13+6 weeks of gestation between August 2010 and October 2015 at the Copenhagen University Hospital Rigshospitalet, Denmark, and 91 uncomplicated singleton pregnancies matched by time of the routine first-trimester blood sampling at 8-13+6 weeks. Descriptive statistical analyses were performed for maternal characteristics and obstetric and medical history for the case versus the control group. Concentrations of mid-regional pro-atrial natriuretic peptide, placental growth factor, soluble fms-like tyrosine kinase-1, and pregnancy-associated plasma protein A between early-onset preeclampsia cases and the control group were compared using Students t-test and the Mann-Whitney U test. Biochemical marker concentrations were converted into multiples of the expected median values after adjustment for gestational age. RESULTS: Mid-regional pro-atrial natriuretic peptide levels were not significantly different between early-onset preeclampsia cases and the control group in the first trimester of pregnancy. As expected, both placental growth factor and pregnancy-associated plasma protein A levels were significantly lower in early-onset preeclampsia, whereas soluble fms-like tyrosine kinase-1 levels were not statistically significantly different. CONCLUSION: The maternal first-trimester concentration of mid-regional pro-atrial natriuretic peptide, a peptide with multiple biological functions including a relation to cardiovascular disease, was not significantly different in women with early-onset preeclampsia.

Thiamine for the Treatment of Cardiac Arrest-Induced Neurological Injury: A Randomized, Blinded, Placebo-Controlled Experimental Study.

Background Thiamine supplementation has demonstrated protective effects in a mouse model of cardiac arrest. The aim of this study was to investigate the neuroprotective effects of thiamine in a clinically relevant large animal cardiac arrest model. The hypothesis was that thiamine reduces neurological injury evaluated by neuron-specific enolase levels. Methods and Results Pigs underwent myocardial infarction and subsequently 9 minutes of untreated cardiac arrest. Twenty minutes after successful resuscitation, the pigs were randomized to treatment with either thiamine or placebo. All pigs underwent 40 hours of intensive care and were awakened for assessment of functional neurological outcome up until 9 days after cardiac arrest. Nine pigs were included in both groups, with 8 in each group surviving the entire intensive care phase. Mean area under the curve for neuron-specific enolase was similar between groups, with 81.5 µg/L per hour (SD, 20.4) in the thiamine group and 80.5 µg/L per hour (SD, 18.3) in the placebo group, with an absolute difference of 1.0 (95% CI, -57.8 to 59.8; P=0.97). Likewise, there were no absolute difference in neurological deficit score at the end of the protocol (2 [95% CI, -38 to 42]; P=0.93). There was no absolute mean group difference in lactate during the intensive care period (1.1 mmol/L [95% CI, -0.5 to 2.7]; P=0.16). Conclusions In this randomized, blinded, placebo-controlled trial using a pig cardiac arrest model with myocardial infarction and long intensive care and observation for 9 days, thiamine showed no effect in changes to functional neurological outcome or serum levels of neuron-specific enolase. Thiamine treatment had no effect on lactate levels after successful resuscitation.