Association between postoperative delirium and postoperative cerebral oxygen desaturation in older patients after cardiac surgery.

BACKGROUND: Near-infrared spectroscopy non-invasively measures regional cerebral oxygen saturation. Intraoperative cerebral desaturations have been associated with worse neurological outcomes. We investigated whether perioperative cerebral desaturations are associated with postoperative delirium in older patients after cardiac surgery. METHODS: Patients aged 70 yr and older scheduled for on-pump cardiac surgery were included between 2015 and 2017 in a single-centre, prospective, observational study. Baseline cerebral oxygen saturation was measured 1 day before surgery. Throughout surgery and after ICU admission, cerebral oxygen saturation was monitored continuously up to 72 h after operation. The presence of delirium was assessed using the confusion assessment method for the ICU. Association with delirium was evaluated with unadjusted analyses and multivariable logistic regression. RESULTS: Ninety-six of 103 patients were included, and 29 (30%) became delirious. Intraoperative cerebral oxygen saturation was not significantly associated with postoperative delirium. The lowest postoperative cerebral oxygen saturation was lower in patients who became delirious (P=0.001). The absolute and relative postoperative cerebral oxygen saturation decreases were more marked in patients with delirium (13 [6]% and 19 [9]%, respectively) compared with patients without delirium (9 [4]% and 14 [5]%; P=0.002 and P=0.001, respectively). These differences in cerebral oxygen saturation were no longer present after excluding cerebral oxygen saturation values after patients became delirious. Older age, previous stroke, higher EuroSCORE II, lower preoperative Mini-Mental Status Examination, and more substantial absolute postoperative cerebral oxygen saturation decreases were independently associated with postoperative delirium incidence. CONCLUSIONS: Postoperative delirium in older patients undergoing cardiac surgery is associated with absolute decreases in postoperative cerebral oxygen saturation. These differences appear most detectable after the onset of delirium. CLINICAL TRIAL REGISTRATION: NCT02532530.

The Effect of Deep Versus Moderate Neuromuscular Block on Surgical Conditions and Postoperative Respiratory Function in Bariatric Laparoscopic Surgery: A Randomized, Double Blind Clinical Trial.

BACKGROUND: In recent literature, it has been suggested that deep neuromuscular block (NMB) improves surgical conditions during laparoscopy; however, the evidence supporting this statement is limited, and this was not investigated in laparoscopic bariatric surgery. Moreover, residual NMB could impair postoperative respiratory function. We tested the hypotheses that deep NMB could improve the quality of surgical conditions for laparoscopic bariatric surgery compared with moderate NMB and investigated whether deep NMB puts patients at risk for postoperative respiratory impairment compared with moderate NMB. METHODS: Sixty patients were evenly randomized over a deep NMB group (rocuronium bolus and infusion maintaining a posttetanic count of 1-2) and a moderate NMB group (rocuronium bolus and top-ups maintaining a train-of-four count of 1-2). Anesthesia was induced and maintained with propofol and remifentanil. The primary outcome measures were the quality of surgical conditions assessed by a single surgeon using a 5-point rating scale (1 = extremely poor, 5 = optimal), the number of intra-abdominal pressure increases >18 cmH2O and the duration of surgery. Secondary outcome measure was the postoperative pulmonary function assessed by peak expiratory flow, forced expiratory volume in 1 second, and forced vital capacity, and by the need for postoperative respiratory support. Data are presented as mean ± standard deviation with estimated treatment effect (ETE: mean difference [95% confidence interval]) for group comparisons. RESULTS: There was no statistically significant difference in the surgeon's rating regarding the quality of the surgical field between the deep and moderate NMB group (4.2 ± 1.0 vs 3.9 ± 1.1; P = .16, respectively; ETE: 0.4 [-0.1, 0.9]). There was no difference in the proportional rating of surgical conditions over the 5-point rating scale between both groups (P = .91). The number of intra-abdominal pressure increases >18 cmH2O and the duration of surgery were not statistically different between the deep and moderate NMB group (0.2 ± 0.9 vs 0.3 ± 1.0; P = .69; ETE: -0.1 [-0.5, 0.4] and 61.3 ± 15.1 minutes vs 70.6 ± 20.8 minutes; P = .07, ETE: -9.3 [-18.8, 0.1], respectively). All the pulmonary function tests were considerably impaired in both groups when compared with baseline (P < .001). There was no statistically significant difference in the decrease in peak expiratory flow, forced expiratory volume in 1 second, and forced vital capacity (expressed as % change from baseline) between the deep and the moderate NMB group. CONCLUSIONS: Compared with a moderate NMB, there was insufficient evidence to conclude that deep NMB improves surgical conditions during laparoscopic bariatric surgery. Postoperative pulmonary function was substantially decreased after laparoscopic bariatric surgery independently of the NMB regime that was used. The study is limited by a small sample size.

Influence of continuously evolving transcatheter aortic valve implantation technology on cerebral oxygenation.

This study assessed the influence of the evolution in Transcatheter Aortic Valve Implantation technology on cerebral oxygenation. Cerebral oxygenation was measured continuously with Near-Infrared Spectroscopy and compared retrospectively between balloon-expandable, self-expandable and differential deployment valves which were implanted in 12 (34%), 17 (49%) and 6 patients (17%), respectively. Left and right SctO2 values were averaged at four time points and used for analysis (i.e. at baseline, balloon-aortic valvuloplasty, valve deployment, and at the end of the procedure). During balloon-aortic valvuloplasty and valve deployment, cerebral oxygenation decreased in patients treated with balloon or self-expandable valves (balloon-expandable: p = 0.003 and p = 0.002; self-expandable: p < 0.001 and p = 0.003, respectively). The incidence of cerebral desaturations below 80% of baseline was significantly larger in patients treated with balloon-expandable valves (p = 0.001). In contrast, patients who received differential deployment valves never experienced a cerebral desaturation below 80% of baseline. Furthermore, both the incidence and duration below a cerebral oxygenation of 55% was significantly different between balloon and self-expandable valves (p = 0.038 and p = 0.018, respectively). This study demonstrated that Transcatheter Aortic Valve Implantation procedures are associated with significant cerebral desaturations, especially during balloon-aortic valvuloplasty and valve deployment. Moreover, our results showed that latest innovations in Transcatheter Aortic Valve Implantation technology beneficially influenced the adequacy of cerebral perfusion.

Diagnostic error in the Emergency Department: follow up of patients with minor trauma in the outpatient clinic.

BACKGROUND: The Emergency Department (ED) is prone to diagnostic error. Most frequent diagnostic errors involved "minor" trauma. Our goal was to determine how frequently a missed diagnosis was detected during follow up and to determine the frequency and causes of primary missed diagnosis and diagnostic error. METHODS: A retrospective single centre study review, during 6 months including all patients presenting to the outpatient clinic after ED admission with a minor trauma. We defined primary missed diagnosis versus diagnostic error. Demographic data were collected in Excel file and analyzed using Χ2 and unpaired T-test. RESULTS: Inclusion of 56 patients leading to 57 missed diagnoses representing 1.39% of all minor trauma patients presenting to the ED. History and physical examination notes were incomplete or inadequate in respectively 17/56 and 20/56. Most frequently missed diagnoses were ankle (13/57), wrist (8/57) and foot (7/57) fractures. Causes for diagnostic error could be categorized into two main groups: failure to perform adequate history taking and/or physical examination and failure to order or correctly interpret technical investigation. In 6 cases (0.14%) diagnostic error was confirmed. All other cases were defined as primary missed diagnosis. DISCUSSION: Emergency physicians have to remain vigilant to prevent and avoid primary missed diagnosis (PMD) and diagnostic error (DE), certainly in case of minor trauma patients, representing a large proportion of ED patients. We observed a prevalence of 1.39% of missed diagnoses within a six month study period. This is comparable to previous studies (1% ). However in our study both primary missed diagnoses and DE were included. Using this definition we saw that only one case could be attributed to negligence and DE had a prevalence of 0.14% (6 cases). X-rays remain the mainstay investigation for minor trauma patients, however in certain selected cases (pelvic and spinal trauma) we advise early CT-scan.Follow up in an outpatient clinic or other forms of planned follow up have to be provided and help to reduce PMD and DE. CONCLUSION: Both primary missed diagnosis and diagnostic error have relatively low prevalence but have a serious impact on patients, hospitals and medical services. Planned follow up after adequate explanation can help to prevent diagnostic error and detect primary missed diagnosis, thereby reducing time to final diagnosis and risks for medico legal litigation. Reassessment of diagnostic error on a timely basis can be used as a key performance indicator in a quality assessment program.

Myectomy and mitral repair through the left atrium in hypertrophic obstructive cardiomyopathy: the preferred approach for contemporary surgical candidates?

OBJECTIVE: Patients with hypertrophic obstructive cardiomyopathy due to diffuse hypertrophy extending to or below the papillary muscles are poor candidates for alcohol septal ablation and suboptimal candidates for transaortic septal myectomy. In addition, the outflow obstruction is often aggravated by an abnormal mitral valve and subvalvular apparatus. METHODS: We performed transatrial myectomy in 12 patients with diffuse hypertrophy, who were highly symptomatic despite maximal medical therapy. All had at least moderate mitral regurgitation and systolic anterior motion. The anterior mitral leaflet (AML) was detached from commissure to commissure, allowing an easy myectomy through this AML toward the base of the anterior papillary muscle, with mobility fully restored. The abnormal chordae from the septum to the anterior papillary muscle and AML were divided. The continuity of this AML was restored with augmentation using an autologous pericardial patch. The height of the posterior mitral leaflet was reduced and the repair completed using an oversized annuloplasty ring. RESULTS: The peak intraventricular gradients decreased spectacularly from 98.8 ± 6.29 to 19.2 ± 13.4 mm Hg (P < .001), and the systolic anterior motion and mitral regurgitation disappeared. One patient died of left ventricular diastolic dysfunction. All other patients left the hospital in New York Heart Association class I or II. CONCLUSIONS: We believe that this technique is preferable for patients with hypertrophic obstructive cardiomyopathy and diffuse hypertrophy extending to the midportion of the left ventricle or beyond. It results in disappearance of outflow tract gradients and allows correction of the mitral valve abnormality.