Postoperative cognitive dysfunction after beach chair positioning compared to supine position in orthopaedic surgery in the elderly.

INTRODUCTION: Postoperative cognitive dysfunction (POCD) occurs in up to 26% of patients older than 60 years 1 week after non-cardiac surgery. Intraoperative beach chair positioning (BCP) is advantageous for some types of shoulder surgery. However, this kind of positioning leads to a downward bound redistribution of blood volume, with possible hypoperfusion of the brain. We hypothesized that patients > 60 years undergoing orthopaedic shoulder surgery in a BCP might experience more POCD than patients operated in the supine position (SP). MATERIAL AND METHODS: A single-centre, prospective observational trial of 114 orthopaedic patients was performed. Study groups were established according to the type of intraoperative positioning. Anaesthesiological management was carried out similarly in both groups, including types of anaesthetics and blood pressure levels. POCD was evaluated using the Trail Making Test, the Letter-Number Span and the Regensburger Word Fluency Test. The frequency of POCD 1 week after surgery was considered primary outcome. RESULTS: Baseline characteristics, including duration of surgery, were comparable in both groups. POCD after 1 week occurred in 10.5% of SP patients and in 21.1% of BCP patients (p = 0.123; hazard ratio 2.0 (CI 95% 0.794-5.038)). After 4 weeks, the incidence of POCD decreased (SP: 8.8% vs. BCP: 5.3%; p = 0.463). 12/18 patients with POCD showed changes in their Word Fluency Tests. Near-infrared spectroscopy (NIRS) values were not lower in patients with POCD compared to those without POCD (54% (50/61) vs. 57% (51/61); p = 0.671). CONCLUSION: POCD at 1 week after surgery tended to occur more often in patients operated in beach chair position compared to patients in supine position without being statistically significant.

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

STUDY OBJECTIVE: Early 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. DESIGN: Single Center Observational Study. SETTING: Post Anesthesia Care Units at a German tertiary medical center. PATIENTS: 30,075 patients receiving general anesthesia for surgery. MEASUREMENTS: Delirium 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 RESULTS: Out 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. CONCLUSIONS: Our 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.

"High ankle block" for surgery at the ankle joint.

BACKGROUND: Surgery around the ankle is increasingly embedded in outpatient treatment concepts. Unfortunately, the classic "ankle block" as a concept of regional anesthesia is inappropriate for surgery around the ankle because the injection sites are too distal to block this specific region. METHODS: The "high ankle block" avoids this disadvantage by dislocating the injection points 15 cm proximal to the malleoli. Three of five peripheral nerves necessary to perform the block can be reached by a circumferential subcutaneous wall. The Posterior Tibial Nerve and the Deep Peroneal Nerve are addressed by an ultrasound guided approach. RESULTS: The efficacy of the technique is highlighted by a case series (3 cases) in which the new blockade was used as a stand-alone procedure, i.e. without additional general anesthesia. CONCLUSIONS: The "high ankle block" may serve as an ultrasound guided expansion to the classic techniques, extending the operative spectrum to the ankle region.

[Development of a giant bulla under spontaneous breathing by self-inflicted lung injury in a patient with COVID-19 pneumonia]. / Entwicklung einer Riesenbulla unter Spontanatmung durch "patient self-inflicted lung injury" bei COVID-19-Pneumonie.

The outbreak of SARS-CoV­2 and the associated COVID-19 pandemic pose major challenges to healthcare systems worldwide. New data on diagnosis, clinical presentation and treatment of the disease are published on a daily basis. This case report describes the fatal course of severe COVID-19 pneumonia in an 81-year-old patient with no previous pulmonary disease who developed a giant bulla during non-invasive high-flow oxygen therapy. Virus-induced diffuse destruction of alveolar tissue or patient self-inflicted lung injury (P-SILI) are discussed as possible pathomechanisms. Future studies must determine whether lung-protective mechanical ventilation with high levels of sedation and paralysis to suppress spontaneous respiratory drive and to reduce transpulmonary pressure can prevent structural lung damage induced both by the virus and P­SILI in COVID-19 patients with ARDS.

Functional Testing for Tranexamic Acid Duration of Action Using Modified Viscoelastometry.

INTRODUCTION: Tranexamic acid (TXA) is the standard medication to prevent or treat hyperfibrinolysis. However, prolonged inhibition of lysis (so-called "fibrinolytic shutdown") correlates with increased mortality. A new viscoelastometric test enables bedside quantification of the antifibrinolytic activity of TXA using tissue plasminogen activator (TPA). MATERIALS AND METHODS: Twenty-five cardiac surgery patients were included in this prospective observational study. In vivo, the viscoelastometric TPA test was used to determine lysis time (LT) and maximum lysis (ML) over 96 h after TXA bolus. Additionally, plasma concentrations of TXA and plasminogen activator inhibitor 1 (PAI-1) were measured. Moreover, dose effect curves from the blood of healthy volunteers were performed in vitro. Data are presented as median (25-75th percentile). RESULTS: In vivo TXA plasma concentration correlated with LT (r = 0.55; p < 0.0001) and ML (r = 0.62; p < 0.0001) at all time points. Lysis was inhibited up to 96 h (LTTPA-test: baseline: 398 s [229-421 s] vs. at 96 h: 886 s [626-2,175 s]; p = 0.0013). After 24 h, some patients (n = 8) had normalized lysis, but others (n = 17) had strong lysis inhibition (ML <30%; p < 0.001). The high- and low-lysis groups differed regarding kidney function (cystatin C: 1.64 [1.42-2.02] vs. 1.28 [1.01-1.52] mg/L; p = 0.002) in a post hoc analysis. Of note, TXA plasma concentration after 24 h was significantly higher in patients with impaired renal function (9.70 [2.89-13.45] vs.1.41 [1.30-2.34] µg/mL; p < 0.0001). In vitro, TXA concentrations of 10 µg/mL effectively inhibited fibrinolysis in all blood samples. CONCLUSIONS: Determination of antifibrinolytic activity using the TPA test is feasible, and individual fibrinolytic capacity, e.g., in critically ill patients, can potentially be measured. This is of interest since TXA-induced lysis inhibition varies depending on kidney function.

Functional testing of tranexamic acid effects in patients undergoing elective orthopaedic surgery.

Tranexamic acid (TXA) can reduce blood loss and transfusion rates in orthopaedic surgery. In this regard, a new viscoelastometric test (TPA-test, ClotPro), enables the monitoring of TXA effects. This prospective observational study evaluated and correlated TXA plasma concentrations (cTXA) following intravenous and oral administration in patients undergoing elective orthopaedic surgery with lysis variables of TPA-test. Blood samples of 42 patients were evaluated before TXA application and 2, 6, 12, 24 and 48 h afterwards. TPA-test was used to determine lysis time (LT) as well as maximum lysis (ML) and cTXA was measured using Ultra-High-Performance-Liquid-Chromatography/Mass-Spectrometry. Data are presented as median (min-max). LTTPA-test and MLTPA-test correlated with cTXA (r = 0.9456/r = 0.5362; p < 0.0001). 2 h after intravenous TXA administration all samples showed complete lysis inhibition (LTTPA-test prolongation: T1: 217 s (161-529) vs. T2: 4500 s (4500-4500);p < 0.0001), whereas after oral application high intraindividual variability was observed as some samples showed only moderate changes in LTTPA-test (T1: 236 s (180-360) vs. T2: 4500 s (460-4500); p < 0.0001). Nevertheless, statistically LTTPA-test did not differ between groups. MLTPA-test differed 2 h after application (i.v.: 9.0% (5-14) vs. oral: 31% (8-97); p = 0.0081). In 17/21 samples after oral and 0/21 samples after intravenous administration cTXA was < 10 µg ml-1 2 h after application. TPA-test correlated with cTXA. MLTPA-test differed between intravenous and oral application 2 h after application. Most patients with oral application had TXA plasma concentration < 10 µg ml-1. The duration of action did not differ between intravenous and oral application. Additional studies evaluating clinical outcomes and side-effects based on individualized TXA prophylaxis/therapy are required.

Influence of insufflated carbon dioxide on abdominal temperature compared to oesophageal temperature during laparoscopic surgery.

BACKGROUND: Body core temperature is an important vital parameter during surgery and anaesthesia. It is influenced by several patient-related and surgery-related factors. Laparoscopy is considered beneficial in terms of a variety of parameters, for example, postoperative pain and length of hospital stay. Non-humidified, non-warmed insufflated CO2 applied during laparoscopy is standard of care. This prospective observational trial therefore evaluates the impact of non-humidified CO2 at room temperature on abdominal temperature and its correlation to body core temperature. METHODS: Seventy patients undergoing laparoscopic surgery were included in this prospective observational study. Temperature was measured oesophageal and abdominal before induction of anaesthesia (T1), right before skin incision (T2), 15 min, 30 min and 60 min after skin incision. All patients were treated according to actual guidelines for perioperative temperature measurement. RESULTS: Body core temperature and abdominal temperature correlated moderately (r = 0.6123; p < 0.0001). Bland-Altman plot for comparison of methods showed an average difference of 0.4 °C (bias - 0.3955; 95% agreement of bias from - 2.365 to 1.574). Abdominal temperature further decreased after establishing pneumoperitoneum (T2: 36.2 °C (35.9/36.4) to T5: 36.1 °C (35.6/36.4); p < 0.0001), whereas oesophageal temperature increased (T2: 36.2 °C (35.9/36.4) to 36.4 °C (36.0/36.7); p = 0.0296). Values of oesophageal and abdominal measurement points differed at T4 (36.3 °C (36.0/36.6) vs. 36.1 °C (35.4/36.6); p < 0.0001) and T5 (36.4 °C (36.0/36.7) vs. 36.1 °C (35.6/36.4) p = 0.0003). CONCLUSION: This prospective observational trial shows the influence of insufflated, non-humidified carbon dioxide at room temperature on abdominal temperature during laparoscopic surgery. We show that carbon dioxide applied at these conditions decreases abdominal temperature and therefore might be a risk factor for perioperative hypothermia.

Postoperative nausea and vomiting in bariatric surgery in comparison to non-bariatric gastric surgery.

INTRODUCTION: Postoperative nausea and vomiting (PONV) are complications of general anesthesia. Patient-specific factors, type of surgery and a variety of drugs determine the frequency. Clinical experience shows nausea and vomiting to be very frequent in morbidly obese patients undergoing bariatric surgery. AIM: To detect the onset and extent of nausea and vomiting in the group of morbidly obese patients undergoing laparoscopic bariatric surgery. MATERIAL AND METHODS: We conducted a retrospective data bank analysis (since 2004) of all patients with body mass index > 35 kg/m2 undergoing laparoscopic bariatric surgery in comparison to patients with a body mass index < 35 kg/m2 undergoing gastric surgery. Propensity score matching was applied to minimize bias effects. The frequency of postoperative nausea was defined as the primary outcome parameter. RESULTS: One hundred and thirty-eight patients were included. There was a significant difference between the morbidly obese group and the control group concerning the frequency of postoperative nausea (15.9% vs. 55.1%; p < 0.001). In patients receiving volatile anesthetics a significant difference between groups concerning frequency of PONV was not observed. Intravenous anesthetics were suitable to reduce PONV in the control group but not in the morbidly obese group (12.5% vs. 56.8%, p < 0.001). With given prophylaxis PONV events still occurred in 15.6% vs. 48.8% (p = 0.003). CONCLUSIONS: Morbidly obese patients undergoing laparoscopic bariatric surgery are at higher risk of suffering from PONV than non-morbidly obese patients. To reduce the PONV incidence in morbidly obese patients, further research, especially focusing on more efficient use of antiemetic drugs, seems to be necessary.

The influence of body mass index on temperature management during general anaesthesia-A prospective observational study.

RATIONALE, AIMS, AND OBJECTIVES: During general anaesthesia, body core temperature is influenced by several factors that are either anaesthesia-related (type and duration of anaesthesia and fluid management), surgery-related (type of surgery and extent of the surgical procedure), or patient-related (age, gender, body weight, and preoperative body core temperature). Interestingly, data concerning body mass index (BMI) and its influence on patients' temperature are sparse. The aim of this study was to evaluate the impact of BMI on body core temperature under general anaesthesia. METHODS: A single centre, prospective, observational study was conducted at a university hospital. Two cohorts (lower limb surgery and abdominal surgery) were evaluated. Patients were treated according to actual German guidelines for the prevention of hypothermia. Temperature was measured sublingually prior to anaesthesia and during the first 60 minutes of anaesthesia. Each cohort was divided in three subgroups (BMI < 24 kg m-2 , BMI 25-34.9 kg m-2 , and BMI > 35 kg m-2 ) according to body weight. RESULTS: A total of 206 patients were evaluated. One hundred four underwent lower limb surgery; 102 underwent abdominal surgery. After induction of anaesthesia, temperature dropped in all subgroups, but this decline was more pronounced in patients with lower BMI. Significant differences concerning temperature changes were observed in abdominal surgery between low and high BMI groups. After 60 minutes of anaesthesia, group-dependent temperature differences had levelled out, and relevant differences compared with preoperative temperatures could no longer be observed in any of the groups. CONCLUSION: Current guidelines provide effective protection against perioperative hypothermia. In the current study, this was true for obese as well as normal weight patients.

Preemptive volume therapy to prevent hemodynamic changes caused by the beach chair position: hydroxyethyl starch 130/0.4 versus Ringer's acetate-a controlled randomized trial.

BACKGROUND: Hemodynamic instability frequently occurs in beach chair positioning for surgery, putting patients at risk for cerebral adverse events. This study examined whether preoperative volume loading with crystalloids alone or with a crystalloid-colloid combination can prevent hemodynamic changes that may be causative for unfavorable neurologic outcomes. METHODS: The study randomly assigned 43 adult patients undergoing shoulder surgery to 3 study groups. Each group received an infusion of 500 mL of Ringer's acetate between induction of anesthesia and being placed in the beach chair position. The crystalloid group received an additional bolus of 1000 mL Ringer's acetate. The hydroxyethyl starch group was administered an additional bolus of 500 mL of 6% hydroxyethyl starch 130/0.4. Hemodynamic monitoring was accomplished via an esophageal Doppler probe. Cerebral oxygen saturation was examined with near-infrared spectroscopy. Changes in stroke volume variation between the prone and beach chair positions were defined as the primary outcome parameter. Secondary outcomes were changes in cardiac output and cerebral oxygen saturation. RESULTS: The control group was prematurely stopped after enrollment of 4 patients because of adverse events. In the hydroxyethyl starch group, stroke volume variation remained constant during positioning maneuvers (P = .35), whereas a significant increase was observed in the Ringer's acetate group (P < .01; P = .014 for intergroup comparison). This was also valid for changes in cardiac output. Cerebral oxygen saturation significantly decreased in both groups. CONCLUSIONS: Preprocedural boluses of 500 mL of 6% hydroxyethyl starch 130/0.4 as well as 1000 mL of Ringer's acetate were efficient in preserving hemodynamic conditions during beach chair position.

Evaluation of pain relief sufficiency using the Cumulative Analgesic Consumption Score (CACS) and its modification (MACS).

Postoperative pain is one of the major complications in general and bariatric surgery, associated with ongoing problems such as ileus, pneumonia and prolonged mobilization. In this study, patients undergoing bariatric surgery were analyzed according to their postoperative pain relief regime. In one group patients were treated with a patient-controlled analgesia (PCA) device, while the other group was treated with oral and intravenous analgesic medication. The aim of this study was to analyze which postoperative pain relief therapy would be more appropriate. We chose the Cumulative Analgesic Consumption Score (CACS) and Numeric Rating Scale (NRS) for pain measurement. For better comparison, we performed a modification of CACS according to PCA treatment. We observed better pain relief in the PCA group. Furthermore, we observed an advantage of treatment with laxatives in patients treated with PCA. In conclusion, PCA devices are appropriate instruments for postoperative pain relief in bariatric patients. CACS is a practical tool for postoperative pain measurement, describing individual pain sensation more objectively, although holding further potential in modification.

Comparison of tension band wiring and precontoured locking compression plate fixation in Mayo type IIA olecranon fractures.

Aim of the present study was to compare the clinical and radiographic outcome of tension band wiring and precontoured locking compression plate fixation in patients treated surgically for an isolated olecranon fractures type IIA according to the Mayo classification. Of 26 patients presenting with an isolated Mayo type IIA olecranon fracture, 13 underwent fixation with a precontoured locking compression plate (group A), 13 patients were treated with tension band wiring (group B). At a mean follow-up of 43 months, patients were clinically and radiographically re-examined using the DASH score, the Mayo Elbow Performance score (MEPS) and anteroposterior and lateral radiographs. The mean DASH score was 14 points in group A and 12.5 points in group B. Regarding the MEPS, 92% of the patients in group A achieved a good to excellent results in comparison to 77% in group B. No significant differences between the two groups could be detected regarding the clinical and radiographic outcome. Implant-related irritations requiring hardware removal occurred more frequently in group B (12 vs. 7). Procedure and implant related costs were significantly higher in group A. Tension band wiring is still a preferable surgical method to treat simple isolated olecranon fractures. The patient must be informed that in all likelihood implant removal will be required once the fracture has healed. Fixation with precontoured locking compression plates does not provide better functional and radiographic outcome but is more expensive than tension band wiring.