Probable risk factors for postoperative delirium in patients undergoing spinal surgery

Postoperative delirium and its risk factors had been widely reported in several kinds of surgeries; however, there is only one known article relative to postoperative delirium in spinal surgery. We retrospectively examined the incidence of postoperative delirium and the probable risk factors in patients undergoing spinal surgery in our hospital, with the same aged non-delirium patients as controls, over a 6-month period. Studies about postoperative delirium were reviewed and referenced for variable factors collecting in our study. T tests, χ ² test and logistic regression analysis were performed to evaluate the various factors related to postoperative delirium. A total of 18 patients (3.3%), all of them were aged 54 years or older, had postoperative delirium after surgery. Patients without postoperative delirium aged 54 years or older served as the control group. The percentage of patients older than 65 years (P = 0.003), with comorbid diseases such as diabetes mellitus (P = 0.042) or central nervous system disorders (P = 0.013), with a surgical history (P = 0.028) in delirium group was larger than the control group. The absolute number of medications being taken before the operation in the delirium patients was also more than the control group (P = 0.000). The percentage of patients transfused with 800 mL or more blood was also larger (P = 0.024) in delirium group was larger than the control group. Logistic regression analysis showed that central nervous system disorder (OR 6.480), surgical history (OR 3.499), age older than 65 years (OR 3.390), diabetes mellitus (OR 2.981), transfused 800 mL or more blood (OR 2.537), and hemoglobin less than 100 g/L (OR 0.281) were significantly related to the occurrence postoperative delirium. Our findings suggest that postoperative delirium in spinal surgery can also occurred in younger patients and with an acceptable incidence in total. The risk for postoperative delirium is multifactorial. More prospective research is necessary in order to evaluate these and other risk factors in greater detail.     

Association between perioperative hypotension and postoperative delirium and atrial fibrillation after cardiac surgery: A post-hoc analysis of the DECADE trial

Study objectiveTo test the hypotheses that in adults having cardiac surgery with cardio-pulmonary bypass, perioperative hypotension increases the risk of delirium and atrial fibrillation during the initial five postoperative days.DesignSub-analysis of the DECADE multi-center randomized trial.SettingPatients who had cardiac surgery with cardiopulmonary bypass at the Cleveland Clinic.InterventionsIn the underlying trial, patients were randomly assigned 1:1 to dexmedetomidine or normal saline placebo.MeasurementsIntraoperative mean arterial pressures were recorded at 1-min intervals from arterial catheters or at 1–5-min intervals oscillometrically. Postoperative blood pressures were recorded every half-hour or more often. The co-primary outcomes were atrial fibrillation and delirium occurring between intensive care unit admission and the earlier of postoperative day 5 or hospital discharge. Delirium was assessed twice daily during the initial 5 postoperative days while patients remained hospitalized with the Confusion Assessment Method for the intensive care unit. Assessments were made by trained research fellows who were blinded to the dexmedetomidine administration.Main resultsThere was no significant association between intraoperative hypotension and delirium, with an adjusted odds ratio of 0.94 (95% CI: 0.81, 1.09; P = 0.419) for a doubling in AUC of mean arterial pressure (MAP) <60 mmHg. An increase in intraoperative AUC of MAP <60 mmHg was not significantly associated with the odds of atrial fibrillation (adjusted odds ratio = 0.99; 95% CI: 0.87, 1.11; P = 0.819). Postoperative MAP <70 mmHg per hour 1.14 (97.5% CI: 1.04,1.26; P = 0.002) and MAP <80 mmHg per hour 1.05 (97.5%: 1.01, 1.10; P = 0.010) were significantly associated with atrial fibrillation.ConclusionsIn patients having cardiac surgery with cardio-pulmonary bypass, neither intraoperative nor postoperative hypotension were associated with delirium. Postoperative hypotension was associated with atrial fibrillation, although intraoperative hypotension was not.     

Incidence of preoperative instrumental activities of daily living (IADL) dependence and adverse outcomes in older surgical patients: A systematic review and meta-analysis

Study objectiveInstrumental activities of daily living (IADLs) are essential to patient function and quality of life after surgery. In older surgical patients, the incidence of preoperative IADL dependence has not been well characterized in the literature. This systematic review and meta-analysis aimed to determine the pooled incidence of preoperative IADL dependence and the associated adverse outcomes in the older surgical population.DesignSystematic review and meta-analysis.SettingMEDLINE, MEDLINE Epub Ahead of Print and In-Process, In-Data-Review & Other Non-Indexed Citations, Embase/Embase Classic, Cochrane CENTRAL, and Cochrane Database of Systematic Reviews, ClinicalTrials.Gov, the WHO ICTRP (International Clinical Trials Registry Platform) were searched for relevant articles from 1969 to April 2022.PatientsPatients aged ≥60 years old undergoing surgery with preoperative IADL assessed by the Lawton IADL Scale.InterventionsPreoperative assessment.MeasurementThe primary outcome was the pooled incidence of preoperative IADL dependency. Additional outcomes included post-operative mortality, postoperative delirium [POD], functional status improvement, and discharge disposition.Main resultsTwenty-one studies (n = 5690) were included. In non-cardiac surgeries, the pooled incidence of preoperative IADL dependence was 37% (95% CI: 26.0%, 48.0%) among 2909 patients. Within cardiac surgeries, the pooled incidence of preoperative IADL dependence was 53% (95% CI: 24.0%, 82.0%) among 1074 patients. Preoperative IADL dependence was associated with an increased risk of postoperative delirium than those without IADL dependence (44.9% vs 24.4, OR 2.26; 95% CI: 1.42, 3.59; I²: 0%; P = 0.0005).ConclusionsThere is a high incidence of IADL dependence in older surgical patients undergoing non-cardiac and cardiac surgery. Preoperative IADL dependence was associated with a two-fold risk of postoperative delirium. Further work is needed to determine the feasibility of using the IADL scale preoperatively as a predictive tool for postoperative adverse outcomes.     

Development and validation of a risk score for predicting postoperative delirium after major abdominal surgery by incorporating preoperative risk factors and surgical Apgar score

Study objectiveTo develop and validate a simple delirium-predicting scoring system in patients undergoing major abdominal surgery by incorporating preoperative risk factors and intraoperative surgical Apgar score (SAS).DesignObservational retrospective cohort study.SettingA tertiary general hospital in China.Patients1055 patients who received major abdominal surgery from January 2015 to December 2019.MeasurementsWe collected data on preoperative and intraoperative variables, and postoperative delirium. A risk scoring system for postoperative delirium in patients after major open abdominal surgery was developed and validated based on traditional logistic regression model. The elastic net algorithm was further developed and evaluated.Main resultsThe incidence of postoperative delirium was 17.8% (188/1055) in these patients. They were randomly divided into the development (n = 713) and validation (n = 342) cohorts. Both the logistic regression model and the elastic net regression model identified that advanced age, arrythmia, hypoalbuminemia, coagulation dysfunction, mental illness or cognitive impairments and low surgical Apgar score are related with increased risk of postoperative delirium. The elastic net algorithm has an area under the receiver operating characteristic curve (AUROC) of 0.842 and 0.822 in the development and validation cohorts, respectively. A prognostic score was calculated using the following formula: Prognostic score = Age classification (0 to 3 points) + arrythmia + 2 * hypoalbuminemia + 2 * coagulation dysfunction + 4 * mental illness or cognitive impairments + (10-surgical Apgar score). The 22-point risk scoring system had good discrimination and calibration with an AUROC of 0.823 and 0.834, and a non-significant Hosmer-Lemeshow test P = 0.317 and P = 0.853 in the development and validation cohorts, respectively. The bootstrapping internal verification method (R = 1000) yielded a C-index of 0.822 (95% CI: 0.759–0.857).ConclusionThe prognostic scoring system, which used both preoperative risk factors and surgical Apgar score, serves as a good first step toward a clinically useful predictive model for postoperative delirium in patients undergoing major open abdominal surgery.     

A long duration of intraoperative hypotension is associated with postoperative delirium occurrence following thoracic and orthopedic surgery in elderly

BackgroundPostoperative delirium (POD) is a common surgical complication associated with increased morbidity and mortality in elderly. Although the underlying mechanisms remain elusive, perioperative risk factors were reported to be closely related to its development. This study was designed to investigate the association between the duration of intraoperative hypotension and POD incidence following thoracic and orthopedic surgery in elderly.MethodThe perioperative data from 605 elderly undergoing thoracic and orthopedic surgery from January 2021 to July 2022 were analyzed. The primary exposure was a cumulative duration of mean arterial pressure (MAP) ≤ 65 mmHg. The primary end-point was the POD incidence assessed with confusion assessment method (CAM) or CAM-ICU for three days after surgery. Restricted cubic spline (RCS) was conducted to examine the continuous relationship between the duration of intraoperative hypotension and POD incidence adjusted with patients' demographics and surgery related factors. Then the duration of intraoperative hypotension was categorized into three groups: no hypotension, short (< 5 mins) or long duration (≥ 5 mins) of hypotension for further analysis.ResultThe incidence of POD was 14.7% (89 cases out of 605) within three days after surgery. The duration of hypotension presented a non-linear and “inverted L-shaped” effect on POD development. Compared to no hypotension, long duration (adjusted OR 3.93; 95% CI: 2.07–7.45; P < 0.001) rather than short duration of MAP ≤65 mmHg (adjusted OR 1.18; 95% CI: 0.56–2.50; P = 0.671) was closely related to the POD incidence.ConclusionIntraoperative hypotension (MAP ≤65 mmHg) for ≥5 mins was associated with an increased incidence of POD after thoracic and orthopedic surgery in elderly.     

Completely laparoscopic versus open radical nephrectomy and infrahepatic tumor thrombectomy: Comparison of surgical complexity and prognosis

ObjectiveTo compare the operation complexity and prognosis of completely laparoscopic versus open radical nephrectomy and infrahepatic tumor thrombectomy.MethodsWe reviewed and analyzed the clinical data of 87 patients with infrahepatic tumor thrombus from January 2015 to April 2019 retrospectively. Completely laparoscopic infrahepatic tumor thrombectomy was completed in 41 cases, and open surgery was completed in 46 cases.ResultsAll 41 patients successfully completed laparoscopic operation, and there were no cases of death during the operation. The completely laparoscopic group were older, had smaller renal tumor diameter, shorter median operation time, lower median intraoperative hemorrhage volume, and lower median transfusion volume of suspended red blood cells compared with open surgeries. The proportion of low-level tumor thrombus (Mayo I) in the completely laparoscopic group was higher (63.4%), while the proportion of low-level tumor thrombus in the open surgery group was lower (30.4%) (P = 0.002). The postoperative complications incidence of laparoscopic surgery was 19.5%, which was lower than that of open surgery (47.8%) (P = 0.004). The mean cancer-specific survival time of the laparoscopic surgery group was 36.6 ± 2.5 months, while that of the open surgery group was 32.3 ± 2.7 months (P = 0.277). There was no statistical difference between the two groups.ConclusionAlthough completely laparoscopic radical nephrectomy and infrahepatic tumor thrombectomy is a challenging operation, it could be feasible and safely performed, especially in the hands of highly-experienced laparoscopic urologists for well selected cases.     

The effectiveness of positive airway pressure therapy in reducing postoperative adverse outcomes in surgical patients with obstructive sleep apnea: A systematic review and meta-analysis

ImportanceObstructive sleep apnea (OSA) is prevalent in surgical patients and is associated with an increased risk of adverse perioperative events.Study objectiveTo determine the effectiveness of positive airway pressure (PAP) therapy in reducing the risk of postoperative complications in patients with OSA undergoing surgery.DesignSystematic review and meta-analysis searching Medline and other databases from inception to October 17, 2021. The search terms included: “positive airway pressure,” “surgery,” “post-operative,” and “obstructive sleep apnea.” The inclusion criteria were: 1) adult patients with OSA undergoing surgery; (2) patients using preoperative and/or postoperative PAP; (3) at least one postoperative outcome reported; (4) control group (patients with OSA undergoing surgery without preoperative and/or postoperative PAP therapy); and (5) English language articles.PatientsTwenty-seven studies included 30,514 OSA patients undergoing non-cardiac surgery and 837 OSA patients undergoing cardiac surgery.InterventionPAP therapyMain resultsIn patients with OSA undergoing non-cardiac surgery, PAP therapy was associated with a decreased risk of postoperative respiratory complications (2.3% vs 3.6%; RR: 0.72, 95% CI: 0.51–1.00, asymptotic P = 0.05) and unplanned ICU admission (0.12% vs 4.1%; RR: 0.44, 95% CI: 0.19–0.99, asymptotic P = 0.05). No significant differences were found for all-cause complications (11.6% vs 14.4%; RR: 0.89, 95% CI: 0.74–1.06, P = 0.18), postoperative cardiac and neurological complications, in-hospital length of stay, and in-hospital mortality between the two groups. In patients with OSA undergoing cardiac surgery, PAP therapy was associated with decreased postoperative cardiac complications (33.7% vs 50%; RR: 0.63, 95% CI: 0.51–0.77, P < 0.0001), and postoperative atrial fibrillation (40.1% vs 66.7%; RR: 0.59, 95% CI 0.45–0.77, P < 0.0001).ConclusionIn patients with OSA undergoing non-cardiac surgery, PAP therapy was associated with a 28% reduction in the risk of postoperative respiratory complications and 56% reduction in unplanned ICU admission. In patients with OSA undergoing cardiac surgery, PAP therapy decreased the risk of postoperative cardiac complications and atrial fibrillation by 37% and 41%, respectively.     

Association between obstructive sleep apnea and atrial fibrillation and delirium after cardiac surgery. Sub-analysis of DECADE trial

BackgroundAtrial fibrillation and delirium are common complications after cardiac surgery. Both are associated with increased Intensive Care Unit (ICU) and hospital length of stay, functional decline, 30-day mortality and increase in health care costs. Obstructive Sleep Apnea (OSA) induces deleterious effects in the cardiovascular and nervous systems. We hypothesized that adult patients with preoperative OSA have a higher incidence of postoperative atrial fibrillation and delirium than patients without OSA, after cardiac surgery.MethodsSub-analysis of the DECADE trial at Cleveland Clinic hospitals. Our exposure was OSA, defined by STOP-BANG questionnaire score higher than 5 and/or a preoperative diagnosis of OSA. The primary outcome was atrial fibrillation, defined by clinician diagnosis or documented arrhythmia. The secondary outcome was delirium assessed twice during the initial five postoperative days using the Confusion Assessment Method for ICU. We assessed the association between OSA, and atrial fibrillation and delirium using a logistic regression model adjusted for confounders using inverse probability of treatment weighting.Results590 patients were included in the final analysis. 133 were diagnosed with OSA and 457 had no OSA. Satisfactory balance between groups for most confounders (absolute standardized difference < 0.10) was achieved after weighting. The atrial fibrillation incidence was 37% (n = 49) in the patients with OSA and 33% (n = 150) in the non-OSA patients. OSA was not associated with atrial fibrillation with an estimated odds ratio of 1.22 (95% CI: 0.75,1.99;p = 0.416). The delirium incidence was 17% (n = 22) in patients with OSA and 15% (n = 67) in the non-OSA patients. OSA was not associated with delirium with an estimated odds ratio of 0.93 (95% CI: 0.51,1.69;p = 0.800).ConclusionIn adult patients having cardiac surgery, OSA is not associated with a higher incidence of postoperative atrial fibrillation and delirium. These results suggest different prominent factors rather than OSA affect the incidence of these postoperative outcomes.     

The effect of delirium preventive measures on the occurrence of postoperative cognitive dysfunction in older adults undergoing cardiovascular surgery. The DelPOCD randomised controlled trial

Study objectiveThis trial examines the effect of delirium preventive measures on the incidence of postoperative cognitive dysfunction in older adults.DesignIn a randomised approach, a delirium prevention and a standard care group were compared regarding manifestation of postoperative cognitive dysfunction at seven days, three and twelve months postoperatively (primary outcome). To correct for practice effects and age-depended cognitive decline, a control group of age-matched healthy subjects was included.SettingThe trial was conducted at the University Medical Centre Hamburg between 2014 and 2018, data assessment took place in the Anaesthesia Outpatient Clinic and on the surgical ward.PatientsA total of 609 patients ≥60 years scheduled for cardiovascular surgery were enrolled, allocated treatment was received by 284 patients in the delirium prevention and 274 patients in the standard care group.InterventionThe intervention consisted of a delirium prevention bundle including reorientation measures, sleeping aids and early mobilisation. Measurements: Cognitive functions were assessed via neuropsychological testing of attention, executive functions including word fluency, and verbal memory utilizing a computerised test of attentional performance, the trail making test, the digit span subtest from the Wechsler Adult Intelligence Scale-IV, the verbal learning and memory test, and the Regensburg Word Fluency Test. Assessments were performed preoperatively and at three time points postoperatively (one week, three months and 12 months).Main resultsPostoperative cognitive dysfunction was defined as a clinically meaningful decline in at least two out of nine chosen test parameters compared to the preoperative level (reliable change index ≤ − 1.96). The rates of postoperative cognitive dysfunction were 25.9% (delirium prevention group, n = 284) vs. 28.1% (standard care group, n = 274) [X²(1,n = 433) = 0.245;p = 0.621] at postoperative day seven and declined to 7.8% vs. 6.8% [X²(1,n = 219) = 0.081;p = 0.775] and 1.3% vs. 5.6% (p = 0.215, Fisher's exact test) at three and 12 months following surgery, respectively. The postoperative delirium rates did not differ between the two groups (delirium prevention group: 13.4% vs. standard care group: 17.3%). Attentional performance was impaired shortly after surgery, whereas verbal delayed recall was most frequently affected over the whole postoperative period.ConclusionThese findings suggest that an intervention combining specific measures extracted from established postoperative delirium prevention programs did not reduce the rate of postoperative cognitive dysfunction in older adults.     

Perioperative dexmedetomidine administration to prevent delirium in adults after non-cardiac surgery: A systematic review and meta-analysis

Study objectiveTo evaluate the efficacy of perioperative dexmedetomidine (DEX) administration for preventing delirium in adults after non-cardiac surgery.DesignSystematic review and meta-analysis of randomized controlled trials (RCTs).InterventionsPerioperative administration of DEX to prevent delirium in adults following non-cardiac surgery.MeasurementsThe incidence of postoperative delirium (POD).MethodsThe databases of PubMed, Embase and Cochrane Central Register were searched from inception to Mar 4, 2021 for all available RCTs that assessed DEX for POD in adults after non-cardiac surgery. Risk ratio (RR) with a 95% confidence interval (CI) was calculated for dichotomous data. Standardized mean difference (SMD) was calculated for continuous data. Risk of bias was assessed using the second version of the Cochrane risk-of-bias tool for RCTs (RoB 2.0), and the level of certainty for main outcomes were assessed by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology.Main resultsThirteen studies, including the meta-analysis with a total of 4015 patients (DEX group: 2050 patients; placebo group: 1965 patients), showed that DEX significantly reduced the incidence of POD in adults after non-cardiac surgery compared with control group (RR: 0.60; 95%CI: 0.46 to 0.77, P = 0.0001, I² = 55%, GRADE = moderate). Meanwhile, there was a statistical difference by the subgroup analysis between the mean age ≥ 65 years group and the mean age<65 years group. There were no statistical differences in length of hospital stay following surgery (SMD: -0.36; 95%CI: −0.80 to 0.07, P = 0.1, I² = 97%, GRADE = low) and all-cause mortality rate (RR:0.57; 95%CI: 0.25 to 1.28, P < 0.17, I² = 0%, GRADE = moderate) compared with placebo group. However, Meta-analysis showed that DEX administration significantly resulted in intraoperative bradycardia when compared with placebo group (RR: 1.39; 95%CI: 1.14 to 1.69, P = 0.0009, I² = 0%, GRADE = high), and as well as intraoperative hypotension (RR: 1.25; 95%CI: 1.11 to 1.42, P = 0.0004, I² = 0%, GRADE = high).ConclusionThis systematic review and meta-analysis suggests that perioperative administration of DEX could significantly reduce the incidence of POD in patients elder than 65 years following non-cardiac surgery. However, there was no definite evidence that perioperative DEX could reduce the incidence of POD in patients younger than 65 years of age after non-cardiac surgery. In addition, perioperative DEX administration was associated with an elevated risk of bradycardia and hypotension.     

Intensive glucose control during the perioperative period for diabetic patients undergoing surgery: An updated systematic review and meta-analysis

Study objectiveTo evaluate the impact of intensive glucose control on diabetic patients undergoing surgery.DesignA systematic review and meta-analysis of randomized controlled trials. PubMed, CENTRAL, EMBASE, ISI Web of Science, and CINAHL databases were searched from inception to 13 December 2020.SettingOperating room, postoperative recovery area and ward, up to 30 days after surgery.PatientsDiabetic patients undergoing surgery.InterventionsWe used Review Manager 5.4 to pool the data with a random-effects model. The quality of evidence was rated using the Grading of Recommendations, Assessment, Development and Evaluation system.MeasurementsThe primary outcomes were infectious complications, postoperative mortality, and hypoglycaemia. The secondary outcomes included atrial fibrillation, myocardial infarction, stroke, delirium, renal failure, postoperative mechanical ventilation time, length of intensive care unit (ICU) stay, and hospital stay.Main resultsThirteen studies involving 1582 participants were included. Compared with conventional glucose control, intensive glucose control was associated with a lower risk of infectious complications (risk ratio [RR], 0.35; 95% confidence interval [CI], 0.19–0.63; low-quality evidence), atrial fibrillation (RR, 0.55; 95% CI, 0.42–0.71; high-quality evidence), and renal failure (RR, 0.38; 95% CI, 0.15–0.95; moderate-quality evidence), as well as a shorter length of stay in the ICU (mean difference (MD), −0.55 day; 95% CI, −1.05 to −0.05 days; very-low-quality evidence) and hospital (MD, −1.61 days; 95% CI, −2.78 to −0.44 days; very-low-quality evidence). However, intensive glucose control was associated with a higher risk of hypoglycaemia (RR, 3.00; 95% CI, 1.97–4.55; high-quality evidence). There were no significant differences in postoperative mortality, myocardial infarction, stroke, delirium, or postoperative mechanical ventilation time.ConclusionsIntensive glucose control in diabetic patients is associated with a reduction in some adverse postoperative outcomes including infectious complications, but also appears to increase the risk of hypoglycaemia. Further well-designed studies may be needed to determine appropriate regimens to reduce hypoglycaemia incidence.PROSPERO registration numberCRD42021226138.     

Association between post-operative delirium and use of volatile anesthetics in the elderly: A real-world big data approach

Study objectiveEarly post-operative delirium is a common perioperative complication in the post anesthesia care unit. To date it is unknown if a specific anesthetic regime can affect the incidence of delirium after surgery. Our objective was to examine the effect of volatile anesthetics on post-operative delirium.DesignSingle Center Observational Study.SettingPost Anesthesia Care Units at a German tertiary medical center.Patients30,075 patients receiving general anesthesia for surgery.MeasurementsDelirium was assessed with the Nursing Delirium Screening Scale at the end of the recovery period. Subgroup-specific effects of volatile anesthetics on post-operative delirium were estimated using generalized-linear-model trees with inverse probability of treatment weighting. We further assessed the age-specific effect of volatiles using logistic regression models.Main resultsOut of 30,075 records, 956 patients (3.2%) developed delirium in the post anesthesia care unit. On average, patients who developed delirium were older than patients without delirium. We found volatile anesthetics to increase the risk (Odds exp. (B) for delirium in the elderly 1.8-fold compared to total intravenous anesthesia. Odds increases with unplanned surgery 3.0-fold. In the very old (87 years or older), the increase in delirium is 6.2-fold. This result was confirmed with internal validation and in a logistic regression model.ConclusionsOur exploratory study indicates that early postoperative delirium is associated with the use of volatile anesthetics especially in the sub-cohort of patients aged 75 years and above. Further studies should include both volatile and intravenous anesthetics to find the ideal anesthetic in elderly patients.     

Las medidas ecográficas de la vena cava inferior no predicen hipotensión arterial postinducción anestésica en pacientes tratados mediante cirugía vascular

IntroductionIntraoperative hypotension (IH) is an independent predictor of mortality. Some experts have suggested that ultrasound measurement of the inferior vena cava (IVC) in spontaneous ventilation can predict IH.ObjectiveTo evaluate the capacity of ultrasound measures of IVC in spontaneous ventilation to predict episodes of IH after anaesthesia induction.Patients and methodsWe studied 55 high-risk cardiac patients undergoing vascular surgery. The maximum (dIVCmax) and minimum (dIVCmin) diameter of the IVC were measured and the collapsibility index CI = (dIVCmax-dIVCmin)/dIVCmax was calculated prior to anaesthesia induction. Three definitions of IH were used: systolic blood pressure (SBP) less than 100 mmHg, mean arterial pressure (MAP) less than 60 mmHg, and a decrease in MAP greater than or equal to 30% compared to baseline.ResultsThere were no significant differences in dIVCmax or in CI between patients presenting IH after anaesthesia induction and those who did not. ROC curves for dIVCmax showed an area under the curve of 0.55 (0.39-0.70), 0.69 (0.48-0.90), and 0.57 (0.42-0.73) and ROC curves for the CI were 0.62 (0.47-0.78), 0.60 (0.41-0.78) and 0.62 (0.47-0.78) for the 3 definitions of IH (<100 mmHg, MAP < 60 mmHg, and MAP ≥30% baseline), respectively.ConclusionsUltrasound measurements of IVC in spontaneous ventilation are not good predictors of IH after anaesthesia induction in these patients. The optimal cut-off points show low specificity and moderate sensitivity for predicting IH.     

Postoperative outcomes in older surgical patients with preoperative cognitive impairment: A systematic review and meta-analysis

Study objectiveTo determine the effect of cognitive impairment (CI) and dementia on adverse outcomes in older surgical patients.DesignA systematic review and meta-analysis of observational studies and randomized controlled trials (RCTs). Various databases were searched from their inception dates to March 8, 2021.SettingPreoperative assessment.PatientsOlder patients (≥ 60 years) undergoing non-cardiac surgery.MeasurementsOutcomes included postoperative delirium, mortality, discharge to assisted care, 30-day readmissions, postoperative complications, and length of hospital stay. Effect sizes were calculated as Odds Ratio (OR) and Mean Difference (MD) based on random effect model analysis. The quality of included studies was assessed using the Cochrane Risk Bias Tool for RCTs and Newcastle-Ottawa Scale for observational cohort studies.ResultsFifty-three studies (196,491 patients) were included. Preoperative CI was associated with a significant risk of delirium in older patients after non-cardiac surgery (25.1% vs. 10.3%; OR: 3.84; 95%CI: 2.35, 6.26; I²: 76%; p < 0.00001). Cognitive impairment (26.2% vs. 13.2%; OR: 2.28; 95%CI: 1.39, 3.74; I²: 73%; p = 0.001) and dementia (41.6% vs. 25.5%; OR: 1.96; 95%CI: 1.34, 2.88; I²: 99%; p = 0.0006) significantly increased risk for 1-year mortality. In patients with CI, there was an increased risk of discharge to assisted care (44.7% vs. 38.3%; OR 1.74; 95%CI: 1.05, 2.89, p = 0.03), 30-day readmissions (14.3% vs. 10.8%; OR: 1.36; 95%CI: 1.00, 1.84, p = 0.05), and postoperative complications (40.7% vs. 18.8%; OR: 1.85; 95%CI: 1.37, 2.49; p < 0.0001).ConclusionsPreoperative CI in older surgical patients significantly increases risk of delirium, 1-year mortality, discharge to assisted care, 30-day readmission, and postoperative complications. Dementia increases the risk of 1-year mortality. Cognitive screening in the preoperative assessment for older surgical patients may be helpful for risk stratification so that appropriate management can be implemented to mitigate adverse postoperative outcomes.     

Impact of intraoperative blood pressure,blood pressure fluctuation,and pulse pressure on postoperative delirium in elderly patients with hip fracture: A prospective cohort study

AimPostoperative delirium (PD) is a frequent complication of hip fracture surgery, but its pathophysiology remains poorly understood. We investigated the impact of a single episode of intraoperative hyper/hypotension, blood pressure (BP) fluctuation (ΔMAP), and pulse pressure (PP) on hyper/hypoactive PD in elderly patients undergoing surgery for hip fracture. We also assessed the effect of PD on clinical outcomes.MethodsThis was a prospective 1-year follow-up study of patients over 60 years of age with a primary diagnosis of acute low-energy hip fracture. Perioperative delirium was assessed using the Confusion Assessment Method (CAM); the development of PD and the type, hyperactive or hypoactive PD, were recorded. Cognitive assessment was evaluated using the Short Portable Mental Status Questionnaire (SPMSQ). The lowest and highest BP values were extracted from the patients’ anaesthesia charts. Postoperative complications, reinterventions and 1-month mortality were recorded.ResultsPD occurred in 148 (53%) patients during the first postoperative week, with 75% of the cases diagnosed as hypoactive PD. Patients developing PD of any type were older, had a lower body mass index, higher SPMSQ and Charlson scores, more severe systemic diseases, a lower lowest intraoperative BP, a higher ΔMAP, a lower PP, and a higher postoperative pain score. They also took more drugs and received more blood transfusion intraoperatively. Multivariate logistic regression analyses showed that a higher MAP min had a protective effect on the occurrence of any type of PD, as well as hypoactive and hyperactive. PD had negative effect on outcomes.ConclusionOur results provide evidence of an association between maximal hypotension, the lowest intraoperative mean blood pressure (MAP), ΔMAP, PP, and PD. A progressive decrease in MAP during surgery was associated with the increased odds of developing either type of PD.     

Association between intraoperative body temperature and postoperative delirium: A retrospective observational study

Study objectiveThe effect of perioperative body temperature derangement on postoperative delirium remains unclear. This study aimed to evaluate the association between intraoperative body temperature and postoperative delirium in patients having noncardiac surgery.DesignSingle-center retrospective observational study.SettingTertiary university hospital.PatientAdult patients who had major noncardiac surgery under general anesthesia for at least two hours between 2019 and 2021.InterventionsPatients were classified into three groups according to their intraoperative time-weighted average body temperature: severe hypothermia (<35.0 °C), mild hypothermia (35.0 °C–36.0 °C), and normothermia (≥36.0 °C) groups.MeasurementsThe primary outcome was the risk of delirium occurring within seven days after surgery, which was compared using logistic regression analysis. A multivariable procedure was performed adjusting for potential confounders including demographics, history of hypertension, diabetes, atrial fibrillation or flutter, myocardial infarction, congestive heart failure, and stroke or transient ischemic attack, preoperative use of antidepressants and statins, preoperative sodium imbalance, high-risk surgery, emergency surgery, duration of surgery, and red blood cell transfusion. Cox regression analysis was also performed using the same covariates.Main resultsAmong 27,674 patients analyzed, 5.5% experienced postoperative delirium. The incidence rates of delirium were 6.2% (63/388) in the severe hypothermia group, 6.4% (756/11779) in the mild hypothermia group, and 4.6% (712/15507) in the normothermia group. Compared with the normothermia group, the risk of delirium was significantly higher in the severe hypothermia (adjusted odds ratio, 1.43; 95% confidence interval, 1.04–1.97) and mild hypothermia (1.15; 1.02–1.28) groups. The mild hypothermia group also had a significantly increased risk of cumulative development of delirium than the normothermia group (adjusted hazard ratio 1.14; 95% confidence interval, 1.03–1.26).ConclusionsIntraoperative hypothermia (even mild hypothermia) was significantly associated with an increased risk of postoperative delirium.     

Effects of different BP management strategies on postoperative delirium in elderly patients undergoing hip replacement: A single center randomized controlled trial

Study objectivePostoperative delirium (POD) is a common after hip replacement. Intraoperative blood pressure management may affect postoperative delirium. The aim of this study was to compare the effects of different blood pressure management strategies on POD.DesignA single center randomized controlled trial.SettingThe Second Hospital of Anhui Medical University, Hefei, China.PatientsA total of 150 patients aged 65–80 years underwent hip arthroplasty.InterventionsA random number table was used to divide the patients into three groups: mean blood pressure (MAP) was maintained from 10% to 20% below the baseline (group D), MAP was maintained from baseline to 10% below the baseline (group M), and MAP was maintained from baseline to 10% above the baseline (group H).MeasurementsThe primary endpoint was POD at 1–3 days. The secondary endpoint was the intraoperative MAP and regional cerebral oxygen saturation (rSO₂) value, MAP, Visual Analogue Scale (VAS score) 1–3 days after surgery, the lengths of post anesthesia care unit (PACU) stay and hospital stay and emergence agitation were recorded.Main resultsPatients in group H showed a lower incidence of POD on the first day than those in groups D and M (22% and 16% vs 4%; P = 0.031). There is no difference of incidence of POD on the 2rd and 3rd day postoperatively. Patients in group H received a higher MAP as well as rSO₂ during the operation compared the other two groups (P < 0.05). Compared with groups D and M, emergence agitation was significantly reduced (P = 0.029) and the lengths of PACU stay (P = 0.018) and hospital stay (P = 0.008) were shortened in group H.ConclusionsMaintenance of intraoperative blood pressure from baseline to 10% above the baseline helps to reduce the incidence of POD and emergence agitation and shorten the lengths of PACU stay and hospital stay, and it may be related to increased rSO₂ during the operation.     

Impact of intraoperative hypotension on early postoperative acute kidney injury in cystectomy patients – A retrospective cohort analysis

Study objectiveTo assess the risk for postoperative acute kidney injury (AKI) after major urologic surgery for different intraoperative hypotension thresholds in form of time below a fixed threshold. We hypothesize that the duration of hypotension below a certain hypotension threshold is a risk factor for AKI also in major urologic procedures.DesignRetrospective observational cohort series.SettingSingle tertiary high caseload center.Patients416 consecutive patients undergoing open radical cystectomy, pelvic lymph node dissection and urinary diversion between 2013 and 2019.InterventionsNone.MeasurementsWe analyzed intraoperative data and their correlation to postoperative AKI judged according to the Acute Kidney Injury Network criteria. Patients were divided into groups falling below MAP <65 mmHg, MAP <60 mmHg and MAP <55 mmHg. The probability of developing postoperative AKI using all risk variables as well as the hypotension threshold variables (minutes under a certain threshold) was calculated using logistic regression methods.Main resultsPostoperative AKI was diagnosed in 128/416 patients (30.8%). Multiple logistic regression analysis showed that minutes below a threshold of 65 mmHg (OR 1.010 [1.005–1.015], P < 0.001) and 60 mmHg (OR 1.012 [1.001–1.023], P = 0.02) are associated with an increased risk of AKI. On average, 26.5% (MAP <65 mmHg), 50.0% (MAP <60 mmHg) and 76.5% (MAP <55 mmHg) of minutes below a certain threshold occurred between induction of anesthesia and start of surgery and are thus fully attributable to anesthesiological management.ConclusionsOur results suggest that avoiding intraoperative MAP lower than 65 mmHg and especially lower than 60 mmHg will protect postoperative renal function in cystectomy patients. The time between induction of anesthesia and surgical incision warrants special attention as a relevant share of hypotension occur in this period.     

Impact of length of red blood cells transfusion on postoperative delirium in elderly patients undergoing hip fracture surgery: A cohort study

PurposeThe purpose of the present study was to test whether older red blood cells (RBCs) transfusion results in an increased risk of postoperative delirium (POD) and various in-hospital postoperative complications in elderly patients undergoing hip fracture surgery.Materials and methodsPatients (≥65 years) who underwent hip fracture surgery were enrolled, 179 patients were divided into two groups according to the storage time of the RBCs. The shorter storage time of RBCs transfusion group comprised patients who received RBCs ≤14 days old and the longer storage time of RBCs transfusion group comprised patients who received RBCs >14 days old. The blood samples were collected before anaesthesia induction, 4 and 24 h after RBCs transfusion for the determination of proinflammatory mediators, malondialdehyde, and superoxide dismutase activity.ResultsThere was no difference in the baseline characteristics, the incidence of POD, and the in-hospital postoperative complications between the shorter storage time of RBCs transfusion group and the longer storage time of RBCs transfusion groups (P > 0.05). Compared with the shorter storage time of RBCs transfusion group, the longer storage time of RBCs transfusion caused significantly longer duration of POD (P < 0.05). There were significantly increased plasma levels of IL-8 and malondialdehyde at 24 h and IL-1β at 4 h after RBCs transfusion in the POD group compared with the non-POD group (P < 0.05).ConclusionTransfusion of the longer storage RBCs is not associated with a higher incidence of POD or in-hospital postoperative complications, but with longer duration of POD in elderly patients undergoing hip fracture surgery.     

Methylene blue reduces incidence of early postoperative cognitive disorders in elderly patients undergoing major non-cardiac surgery: An open–label randomized controlled clinical trial

Study objectiveThe purpose of the present study was to investigate whether methylene blue (MB) could reduce the incidences of postoperative delirium (POD) and early postoperative cognitive dysfunction (POCD) in elderly patients undergoing major non-cardiac surgery.DesignProspective, randomized, open–label clinical trial.SettingUniversity-affiliated hospital.PatientsTwo hundred and forty-eight elderly patients scheduled for non-cardiac surgery.InterventionsElderly patients undergoing non-cardiac major surgery were randomly assigned to MB group (n = 124), who receiving intravenous infusion of 2 mg/kg MB within 60 min immediately after anesthetic induction, or control group (n = 124), who receiving equal volume saline in the same way.MeasurementsAll patients were evaluated with delirium and neuropsychological batteries before and after surgery, as well as perioperative adverse events. Two plasma biomarkers superoxide dismutase (SOD) and homocysteine (HCY) were measured pre- and post-operatively.Main resultsThere were total 39 cases(15.7%)experienced POD. The incidence of POD in MB group was significantly less than that in control group (7.3% vs. 24.2%, OR = 0.24, 95%CI: 0.11–0.53, p < 0.001). The incidence of early POCD at postoperative 7th day in MB group was also less than that in control group (16.1% vs. 40.2%, OR = 0.30, 95% CI: 0.16–0.57, p < 0.001). The adverse events were comparable in both groups. In addition, there was no significant correlation between POD/POCD and levels of SOD or HCY.ConclusionWe conclude that intraoperative intravenous 2 mg/kg MB could significantly reduce the incidences of POD and early POCD in elderly surgical patients, while not remarkably increase incidence of perioperative adverse events, suggesting MB may be clinically effective and safe for prevention of early postoperative neurocognitive disorders.