A decade of surgical therapy in an all-comer cohort with type A aortic dissection.

BACKGROUND: We reported on a decade of aortic surgery for type A aortic dissection to assess surgical techniques employed and outcomes over time in an all-comer analysis of a mid-size university cardiosurgical center. METHODS: From 2009 to 2018, 283 patients (189 males and 94 females, mean age 62 years, range 30-85 years), who underwent surgical therapy for type A aortic dissection in our institution were included in a retrospective statistical analysis. RESULTS: Among all the patients, 55.5% of them were hemodynamically stable, 10.3% came in intubated. A neurological deficit was present in 18.9% of cases, extremity malperfusion was noted in 17.4%, and abdominal malperfusion detected in 8.2%. The extent of the aortic dissection corresponded to DeBakey type I in 88% of cases, a thoracoabdominal involvement was seen in 64%. In 51.9% of patients, only the ascending aorta replaced, another 40.6% of patients had proximal arch replacement too. A separate stent placement into the descending aorta was achieved in 13.4% of patients, during surgery (5.7%) or thereafter (7.7%). Overall survival to discharge was 79.5%. Most frequent complications were stroke and paralysis (15.2%), but only visceral malperfusion (OR 9.0) and heart failure mandating ECMO therapy (OR 29.5) were associated with significantly increased mortality. CONCLUSIONS: Surgery for type A aortic dissection is still challenging. Along with the refinement of surgical techniques, the indication for the various procedures has moved from a simplified general strategy to a more individualized concept.

The impact of interleukin serum levels on the prognosis of patients undergoing venoarterial extracorporeal membrane oxygenation.

Extracorporeal life support is increasingly used in the treatment of patients presenting with cardiogenic shock or in need of cardiopulmonary resuscitation. Identifying therapeutic targets and factors associated with the prognosis are highly desirable. The present study analyzed the impact of interleukin 6 and 8 on the outcome of patients undergoing venoarterial extracorporeal membrane oxygenation (VA ECMO). Interleukin 6 and 8 serum levels of 329 patients were analyzed prior to, on days 1 and 5 of VA ECMO therapy. Interleukin 6 and 8 serum levels of surviving and nonsurviving patients were compared. At time points with significant differences, receiver operating characteristics and cutoff levels were analyzed to determine the prognostic value of interleukin serum levels. Survival analysis was performed to compare patients above and below cutoff levels. Interleukin 6 serum levels were significantly elevated in nonsurviving patients prior to VA ECMO initiation. Interleukin 6 and 8 serum levels in nonsurviving patients were significantly elevated on day 1 of VA ECMO. Receiver operating characteristics analysis revealed significant prognostic impact of interleukin 6 and 8 on day 1 of VA ECMO (AUC 0.70 and 0.72). Survival analysis comparing patients above and below the cutoff showed a 1-year survival of 32.6% for IL6 and 20.8% for IL8 above, as well as 66.9% for IL6 and 61.9% for IL8 below the cutoff (P < .05). Interleukin 6 and 8 serum levels demonstrated prognostic value early in VA ECMO therapy. The technical applicability of interleukin reduction raises interest in interleukins 6 and 8 as therapeutic targets.

Shortening of the twitch stabilization period by tetanic stimulation in acceleromyography in infants, children and young adults (STSTS-Study): a prospective randomised, controlled trial.

Acceleromyography is characterised by an increase of the twitch response T1 (first twitch of the train-of-four [TOF]) during first 30 min of monitoring known as the staircase phenomenon. In adults the staircase phenomenon can be avoided by tetanic prestimulation. This study examined, if tetanic prestimulation eliminates the staircase phenomenon in children. After written informed consent, the neuromuscular function of 80 children, 10 in each age group (< 6 months, 6-12 months, 12-24 months, 2-3 years, 3-6 years, 6-12 years, 12-18 years, and ≥ 18 years) was measured on both arms simultaneously over 30 min under general anaesthesia. The ulnaris nerve was stimulated using the TOF technique every 15 s. The twitch response (T1, TOF ratio [TOFR]) was measured by acceleromyography. Before calibration, tetanic prestimmulation (50 Hz for 5 s) was administered to one randomly selected arm. The effect of tetanic prestimulation and age was analysed using general linear models based on the normalized T1 and TOFRs of both arms. Tetanic prestimulation significantly affected T1 values avoiding the staircase phenomenon (p < 0.0001). After 5.8 min [1.0-17.2 min] the normalized T1 values increased to 117% [102-147%] without prestimulation (p < 0.0001) independent of the age group (p = 0.539). The normalized TOFR was stable throughout the observation period of 30 min 100% [95-107%]. Infants (> 12 weeks), children, and young adults (< 18 years) develop similar characteristics of the staircase phenomenon than adults. Tetanic prestimulation prevents the staircase phenomenon in these age groups. The stability of the TOFR reading confirms its value to monitor neuromuscular function over time.Registration: The study was registered as NCT02552875 on Clinical Trials.gov on July 29, 2014.

Extracorporeal Membrane Oxygenation for Massive Pulmonary Embolism as Bridge to Therapy.

Pulmonary Embolism (PE) is a common illness in western countries. The purpose of this study is to report the institutional experience with massive PE and Extracorporeal Membrane Oxygenation (ECMO) in inoperable patients on admission. A retrospective analysis using the institutional ECMO-registry including the time between 2006 and 2017 was performed. During the study period, 75 patients (n = 46 patients venoarterial [VA], n = 29 patients venovenous [VV]) were placed on ECMO for massive PE. The primary support for massive PE consists of VA; however, VV support can be applied as well in selected cases as this work demonstrates. In the VA group, more patients (38 vs. 83%, P = 0.001) required mechanical resuscitation whereas in the VV group a more aggressive ventilation before support was noted (e.g. minute ventilation: VA=8.8 ± 3.7 L/min, VV=11.5 ± 4.5 L/min, P = 0.01). Survival to discharge was similar in VV and VA patients (45 vs. 48%, P = 0.9). Patients who received additional therapeutic interventions after stabilization with ECMO - e.g. surgical thrombectomy - displayed a similar survival compared with those being only anticoagulated (44% vs. 49%, P = 0.40). ECMO is feasible for initial stabilization serving as a bridge to therapy in primarily inoperable patients with massive PE. The principal configuration of support is VA; however, VV can be applied as well in selected hemodynamically compromised cases under aggressive ventilation.

Is there really a benefit of using minimized cardiopulmonary bypass in CABG? A retrospective propensity score-matched study with 5000 cases.

The concept of minimized cardiopulmonary bypass targets at reduction of adverse effects triggered by extracorporeal circulation. In this study, benefits of minimized bypass in CABG were evaluated under particular consideration of patient body mass index and surgeon impact. From 2004 to 2014, 5164 patients underwent coronary bypass surgery (CABG). Conventional cardiopulmonary bypass (CCPB) was used in 2376 patients, minimized cardiopulmonary bypass (MCPB) in 2788 cases. Multivariate regression models were used in the entire cohort and in a propensity score-matched subgroup after expert CABG to figure out clinical differences such as mortality, postoperative renal function, and thromboembolic events. Overall mortality was 1.5% (n = 41) in the MCPB group and 3.5% (n = 82) in CCPB patients (p < 0.001). Postoperative renal failure and hemodialysis occurred in 2.6% (n = 72/MCPB) vs. 5.3% (n = 122/CCPB (p < 0.001). Multivariable regression revealed use of CCPB as risk factor for increased mortality (OR 2.01, p = 0.001), renal failure (OR 1.79, p < 0.001), and myocardial infarction (OR 1.98, p < 0.001) comparable to risk factors such as preoperative ventilation (OR 2.26, p = 0.048), diabetes mellitus (OR 1.68, p = 0.001), and cardiogenic shock (OR 3.81, p = 0.002). Body mass index had no effect on the analyzed outcome parameters (OR 0.92, p = 0.002). Propensity score-matching analysis of an expert CABG subgroup revealed CCPB as risk factor for mortality (OR 2.26, p = 0.004) and postoperative hemodialysis (OR 1.74, p = 0.017). Compared to conventional circuits, minimized bypass use in CABG is associated with lower mortality and less postoperative renal failure. A high body mass index is feasible and not a risk factor for MCPB surgery.

Conventional or minimized cardiopulmonary bypass support during coronary artery bypass grafting? - An analysis by means of perfusion and body mass index.

The use of minimized cardiopulmonary bypass support to reduce the side effects of extracorporeal circulation is still contradictorily discussed. This study compares perfusion operated by conventional (CCPB) and minimized (MCPB) cardiopulmonary bypass support during coronary artery bypass grafting (CABG). This study includes the data of 5164 patients treated at our department between 2004 and 2014. Tissue perfusion during cardiopulmonary bypass support and cardiac arrest was assessed by means of body mass index, hemodilution, blood pressure with corresponding pump flow and venous oxygen saturation, serum lactate, and serum pH. Hemodilution was more pronounced after CCPB: hemoglobin had dropped to 4.47 ± 0.142 g/dL after CCPB and to 2.77 ± 0.148 g/dL after MCPB (P = 0.0022). Despite the higher pump flow in conventional circuits (4.86-4.95 L/min vs. 4.1-4.18 L/min), mean blood pressure was higher during minimized bypass support (53 ± 10 vs. 56 ± 13 mm Hg [aortic clamping], 57 ± 9 vs. 61 ± 12 mm Hg [34°C], 55 ± 9 vs.59 ± 11 mm Hg [aortic clamp removal], P < 0.0001) at all time points. Venous oxygen saturation remained on comparable levels of >70% during both conventional and minimized cardiopulmonary bypass support. The increase in serum lactate was more pronounced after CCPB (8.98 ± 1.28 vs. 3.66 ± 1.25 mg/dL, P = 0.0079), corresponding to a decrease in serum pH to acidotic levels (7.33 ± 0.06 vs. 7.35 ± 0.06, P < 0.0001). These effects were evident in all BMI ranges. Minimized cardiopulmonary bypass support provides efficient perfusion in all BMI ranges and is thus equivalent to conventional circuits.

Platelet sequestration with a new-generation autotransfusion device.

BACKGROUND: Autologous platelet-rich plasma (PRP) can be used either to prevent platelets (PLTs) from lesions during extracorporeal circulation or for wound therapy, when processed into PLT gel. The aim of this study was to evaluate the PLT sequestration abilities of a new-generation autotransfusion device. STUDY DESIGN AND METHODS: In this experimental study the discontinuous, new-generation autotransfusion device XTRA was evaluated using fresh donor blood. The blood was processed in four different size bowls (X55, X125, X175, X225 [bowls' size in mL]) using the device's built-in "PLT sequestration program." PLT functionality was tested using aggregometry; for PLT activation, ß-thromboglobulin (ß-TG) and soluble P-selectin levels were determined. Cell damage was assessed by a morphology score and hypotonic shock response. Additionally, PLTs were tested after 6 hours to identify storage lesions. RESULTS: Platelet recovery in the PRP ranged from 39% to 64% and averaged 6.2-fold PLT enrichment as defined by the increase in PLT concentration. The preparation caused minimal cell damage and a decrease in cell function by only 10%, but a slight activation was observed amounting to 9% of the maximal ß-TG release. The efficiency of the preparation, represented by the PLT recovery rate, increased in a linear fashion with the increasing bowl sizes being tested. After 6 hours of storage the prepared PLTs showed an additional 9% loss in function, but only 4% decrease in viability. CONCLUSION: The autotransfusion device XTRA was capable of high-quality perioperative PRP preparation, and the bowl size was found to have an influence on the efficiency of the preparation.

Development of an algorithm using clinical tests to avoid post-operative residual neuromuscular block.

BACKGROUND: Quantitative neuromuscular monitoring is the gold standard to detect postoperative residual curarization (PORC). Many anesthesiologists, however, use insensitive, qualitative neuromuscular monitoring or unreliable, clinical tests. Goal of this multicentre, prospective, double-blinded, assessor controlled study was to develop an algorithm of muscle function tests to identify PORC. METHODS: After extubation a blinded anesthetist performed eight clinical tests in 165 patients. Test results were correlated to calibrated electromyography train-of-four (TOF) ratio and to a postoperatively applied uncalibrated acceleromyography. A classification and regression tree (CART) was calculated developing the algorithm to identify PORC. This was validated against uncalibrated acceleromyography and tactile judgement of TOF fading in separate 100 patients. RESULTS: After eliminating three tests with poor correlation, a model with four tests (r = 0.844) and uncalibrated acceleromyography (r = 0.873) were correlated to electromyographical TOF-values without losing quality of prediction. CART analysis showed that three consecutively performed tests (arm lift, head lift and swallowing or eye opening) can predict electromyographical TOF. Prediction coefficients reveal an advantage of the uncalibrated acceleromyography in terms of specificity to identify the EMG measured train-of-four ratio < 0.7 (100% vs. 42.9%) and <0.9 (89.7% vs. 34.5%) compared to the algorithm. However, due to the high sensitivity of the algorithm (100% vs. 94.4%), the risk to overlook an awake patient with a train-of-four ratio < 0.7 was minimal. Tactile judgement of TOF fading showed poorest sensitivity and specifity at train of four ratio < 0.9 (33.7%, 0%) and <0.7 (18.8%, 16.7%). CONCLUSIONS: Residual neuromuscular blockade can be detected by uncalibrated acceleromyography and if not available by a pathway of four clinical muscle function tests in awake patients. The algorithm has a discriminative power comparable to uncalibrated AMG within TOF-values >0.7 and <0.3. TRIAL REGISTRATION: Clinical Trials.gov (principal investigator's name: CU, and identifier: NCT03219138) on July 8, 2017.

Neuromuscular blockade improves surgical conditions (NISCO).

BACKGROUND: We examined the impact of muscle relaxation on surgical conditions and patients' postoperative outcome during elective laparoscopic cholecystectomy under balanced anaesthesia. METHODS: After approval and consent, 57 anaesthetized patients were randomly assigned to group no neuromuscular blockade (No NMB) and deep neuromuscular blockade (Deep NMB), i.e. no twitch response to train-of-four nerve stimulation. Laparoscopic cholecystectomy was performed using the 4-trocar technique with a CO2-pneumoperitoneum. Surgical conditions were assessed using a Visual Analogue Scale. Movement of diaphragm or abdominal muscles, inadequate visibility, or breathing and coughing against the ventilator were documented as events reflecting inadequate muscle relaxation. Independently, surgeons could request 0.3 mg/kg rocuronium to improve surgical conditions. Workflow variables were obtained as a surrogate of surgical conditions. Data are presented as mean (95 % confidence interval). The trial is registered at ClinicalTrials.gov (NCT00895778). RESULTS: While in 12 of 25 patients of group "No NMB" one or more adverse events impaired the surgical procedure (p < 0.001), only 1 of 25 patients of group "Deep NMB" showed an adverse event. Deep NMB resulted in an absolute risk reduction of 0.44 (0.23-0.65) and a number needed to treat of 2.3 (1.5-4.4), respectively. Surgeons requested 0.3 mg/kg rocuronium in 10 of 25 cases (40 %) of group "No NMB" only. This dose significantly improved surgical conditions by an average 62 of 100 possible points. All further variables did not differ between groups. CONCLUSIONS: Deep NMB ameliorates surgical conditions for laparoscopic cholecystectomy by improved visibility and reduction of involuntary movements.

Systemic inflammatory response syndrome increases immobility-induced neuromuscular weakness.

OBJECTIVE: Inflammation and immobility are comorbid etiological factors inducing muscle weakness in critically ill patients. This study establishes a rat model to examine the effect of inflammation and immobilization alone and in combination on muscle contraction, histology, and acetylcholine receptor regulation. DESIGN: Prospective, randomized, experimental study. SETTING: Animal laboratory of a university hospital. SUBJECTS: Sprague-Dawley rats. INTERVENTIONS: To produce systemic inflammation, rats (n = 34) received three consecutive intravenous injections of Corynebacterium parvum on days 0, 4, and 8. Control rats (n = 21) received saline. Both groups were further divided to have one hind limb either immobilized by pinning of knee and ankle joints or sham-immobilized (surgical leg). The contralateral nonsurgical leg of each animal served as control (nonsurgical leg). MEASUREMENTS AND MAIN RESULTS: After 12 days, body weight and muscle mass were significantly reduced in all C. parvum animals compared with saline-injected rats. Immobilization led to local muscle atrophy. Normalized to muscle mass, tetanic contraction was reduced in the surgical leg after immobilization (7.64 +/- 1.91 N/g) and after inflammation (8.71 +/- 2.0 N/g; both p < .05 vs. sham immobilization and saline injection, 11.03 +/- 2.26 N/g). Histology showed an increase in inflammatory cells in all C. parvum-injected animals. Immobilization in combination with C. parvum injection had an additive effect on inflammation. Acetylcholine receptors were increased in immobilized muscles and in all muscles of C. parvum-injected animals. CONCLUSIONS: The muscle weakness in critically ill patients can be replicated in our novel rat model. Inflammation and immobilization independently lead to muscle weakness.