Association between postoperative changes in the gut microbiota and pseudopsia after cardiac surgery: prospective observational study.

BACKGROUND: Delirium after cardiac surgery affects mortality, but the mechanism remains unclear. Previous studies have reported gut microbiota are associated with brain activity. Systemic inflammation and antibiotics can damage the gut microbiota after cardiac surgery. We aimed to investigate changes in the gut microbiota and the association between the gut microbiota and delirium after cardiac surgery. METHODS: Twenty-one patients who underwent cardiac surgery were enrolled. Microbiota counts and fecal organic acid concentrations were measured in fecal samples harvested before surgery, just after surgery, and before discharge. To quantify the microbiota, we extracted total RNA fractions and examined gut microbiota composition using 16S and 23S rRNA-targeted quantitative-reverse Transcription-PCR. Postoperative delirium, insomnia, and pseudopsia were assessed for 1 week. Postoperative total bacterial counts changed significantly from 10.2 ± 0.2 log10 cells/g of feces to 9.8 ± 0.5 in the first postoperative samples (p = 0.003) and 10.0 ± 0.4 in the samples before discharge (p = 0.039). Fecal pH was 6.9 ± 0.6 before surgery and 7.4 ± 0.7 in the first postoperative samples (p = 0.001). Postoperative Staphylococcus and Pseudomonas counts were significantly higher in patients with postoperative pseudopsia than in patients without pseudopsia (3.2 ± 1.3 vs. 5.4 ± 0.9; p = 0.012 and 1.7 ± 0.8 vs. 4.6 ± 2.7; p = 0.001). CONCLUSIONS: Total bacterial counts were significantly lower after surgery and until discharge. Fecal pH was significantly higher than preoperative levels. Staphylococcus and Pseudomonas counts were significantly higher in patients with postoperative pseudopsia.

Abnormal composition of gut microbiota contributes to delirium-like behaviors after abdominal surgery in mice.

AIMS: Anesthesia and surgery can cause delirium-like symptoms postoperatively. Increasing evidence suggests that gut microbiota is a physiological regulator of the brain. Herein, we investigated whether gut microbiota plays a role in postoperative delirium (POD). METHODS: Mice were separated into non-POD and POD phenotypes after abdominal surgery by applying hierarchical clustering analysis to behavioral tests. Fecal samples were collected, and 16S ribosomal RNA gene sequencing was performed to detect differences in gut microbiota composition among sham, non-POD, and POD mice. Fecal bacteria from non-POD and POD mice were transplanted into antibiotics-induced pseudo-germ-free mice to investigate the effects on behaviors. RESULTS: α-diversity and ß-diversity indicated differences in gut microbiota composition between the non-POD and POD mice. At the phylum level, the non-POD mice had significantly higher levels of Tenericutes, which were not detected in the POD mice. At the class level, levels of Gammaproteobacteria were higher in the POD mice, whereas the non-POD mice had significantly higher levels of Mollicutes, which were not detected in the POD mice. A total of 20 gut bacteria differed significantly between the POD and non-POD mice. Interestingly, the pseudo-germ-free mice showed abnormal behaviors prior to transplant. The pseudo-germ-free mice that received fecal bacteria transplants from non-POD mice but not from POD mice showed improvements in behaviors. CONCLUSIONS: Abnormal gut microbiota composition after abdominal surgery may contribute to the development of POD. A therapeutic strategy that targets gut microbiota could provide a novel alterative for POD treatment.

Sepsis and Septic Shock Strategies.

Three therapeutic principles most substantially improve organ dysfunction and survival in sepsis: early, appropriate antimicrobial therapy; restoration of adequate cellular perfusion; timely source control. The new definitions of sepsis and septic shock reflect the inadequate sensitivity, specify, and lack of prognostication of systemic inflammatory response syndrome criteria. Sequential (sepsis-related) organ failure assessment more effectively prognosticates in sepsis and critical illness. Inadequate cellular perfusion accelerates injury and reestablishing perfusion limits injury. Multiple organ systems are affected by sepsis and septic shock and an evidence-based multipronged approach to systems-based therapy in critical illness results in improve outcomes.

Delirium in long-term care setting: indicator to severe morbidity.

We aimed to investigate the incidence and characterize predictors associated with delirium in elderly demented and functionally dependent LTC patients. Data collection included: demographic, clinical, functional, nutritional and cognitive data as well as blood counts and chemistry analysis. The tools used to detect delirium were the Confusion Assessment Method (CAM) and the Delirium Rating Scale (DRS), supported by clinical observation. The occurrence of delirium was 34%. The predominant primary etiologies for delirium were infections (58%), following by metabolic abnormalities (36%), and adverse drug effects (18%). The mean duration of delirium was 15.74 days (2-96 days). Independent predictors influencing duration of delirium were low plasma albumin level, high number of comorbid diseases, male gender, advanced age and presence of CVD. Complete resolution of the delirium was found in 33% (30/92), with persistence in 12% (11/92), and no change in 8% (7/92) of the patients. Forty-eight percent (44/92) of the patients died. Most deaths (50%) were in the first month. The main cause of death was infection related (70%), of which bronchopneumonia was predominant (39%), followed by sepsis (32%). Independent predictors of death were infection, advanced age, low plasma albumin level, dehydration and CHF. The early recognition, identification, correction and treatment of underlying conditions especially in very demented, uncooperative and functionally dependent patients may influence their outcome. Any changes in cognitive and functional status are critical in monitoring LTC patients.

Incidence and correlates of delirium in a West African mental health clinic.

OBJECTIVE: To determine the incidence of delirium in those patients presenting to a psychiatric clinic in Nigeria and to examine if any demographic or clinical variables were correlated with this diagnosis. METHOD: A prospective survey design; 264 consecutive new referrals to a psychiatric clinic in Nigeria were assessed for the presence of delirium using a standardised diagnostic scale. Data was analysed for normality and appropriate statistical test employed to examine the relationships between the presence of delirium and demographic and clinical variables. RESULTS: Of individuals presenting to the mental health clinics, 18.2% had delirium. No demographic variable was significant regarding the presence or absence of delirium. With regard to clinical variables duration of current symptoms, referral source and the presence of comorbid physical illness were significantly associated with the presence of delirium. Most delirium was due to infections. Nearly all patients with delirium were prescribed psychotropic medication (95.2%), and most attributed their symptoms to a spiritual cause. CONCLUSION(S): Delirium presents more commonly to psychiatry services in the less developed world compared to the West. Development efforts should focus on recognition and management of delirium to improve outcomes and maximise resources.

Nontraumatic pneumocephalus due to nosocomial Enterobacter cloacae infection.

Nosocomial meningitis is rare, and routine cerebrospinal fluid study is seldom recommended for hospitalized patients with fever and acute delirium. We present a case of Enterobacter cloacae meningitis complicated with a nontraumatic pneumocephalus. Maintaining a high index of suspicion of nosocomial meningitis is crucial in patients with acute delirium and multiple underlying comorbid conditions.

Accidental fall due to abnormal behavior after experiencing a Streptococcus pyogenes infection: febrile delirium or pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection?

An 11-year-old boy with a high fever (39.4 degrees C) presented at a local medical institution. His condition was diagnosed as hemolytic streptococcal infection, and he was prescribed an antibiotic. After returning home, he took a dose of his medication and rested; however, he suddenly began to run around while yelling incomprehensible words. He ran up to his room on the second floor and fell from the second floor window down to the ground. He lost consciousness and was transferred to our department. His history included being born as a twin with a low birth weight and pneumonia at 1 year of age. He regained consciousness on the seventh hospital day and was discharged without any neurological abnormality on the 14th day. His abnormal behavior might have resulted from febrile delirium or an unusual expression of pediatric autoimmune neuropsychiatric disorder associated with a streptococcal infection.

The cause of delirium in patients with hip fracture.

OBJECTIVES: To ascertain the most common causes of delirium, to establish the initiation and timing of delirium, and to determine the duration of delirium in patients with hip fracture. METHODS: Five hundred seventy-one (88%) of 650 patients with hip fracture admitted to 4 New York City hospitals were prospectively interviewed on a daily basis, 5 days a week, with the Confusion Assessment Method for the presence of delirium. The patients were enrolled within 48 hours of admission. Their medical charts and the data collected by the study staff were reviewed and summarized. Two of us (R.S.M. and A.L.S.) reviewed the case summaries independently and assigned a cause based on a previously developed classification system, estimated the onset of the delirious episode, and determined whether the delirium had cleared, improved, or persisted at discharge. Subsequently, discrepancies in cause, timing of initiation, and mental status on discharge between the 2 physicians reviewers were discussed until consensus was reached. RESULTS: The prevalence of delirium was 9.5% (54/ 571; 95% confidence interval, 7.0-11.9). Seven percent of episodes were assigned a definite cause, 20% a probable cause, 11% a possible cause, and 61% were attributable to 1 or more comorbid conditions. Twenty-eight (53%) of 54 subjects developed delirium after surgery. The delirium had cleared or improved in 40 (74%) of 54 subjects at the time of discharge. CONCLUSIONS: Delirium in patients with hip fracture appears to be a different syndrome from that observed in patients who are otherwise medically ill; it also appears to follow a different clinical course. These results have important implications for the management of delirium in patients with hip fracture.