Vasopressor Therapy in Cardiac Surgery-An Experts' Consensus Statement.

Hemodynamic conditions with reduced systemic vascular resistance commonly are observed in patients undergoing cardiac surgery and may range from moderate reductions in vascular tone, as a side effect of general anesthetics, to a profound vasodilatory syndrome, often referred to as vasoplegic shock. Therapy with vasopressors is an important pillar in the treatment of these conditions. There is limited guidance on the appropriate choice of vasopressors to restore and optimize systemic vascular tone in patients undergoing cardiac surgery. A panel of experts in the field convened to develop statements and evidence-based recommendations on clinically relevant questions on the use of vasopressors in cardiac surgical patients, using a critical appraisal of the literature following the GRADE system and a modified Delphi process. The authors unanimously and strongly recommend the use of norepinephrine and/or vasopressin for restoration and maintenance of systemic perfusion pressure in cardiac surgical patients; despite that, the authors cannot recommend either of these drugs with respect to the risk of ischemic complications. The authors unanimously and strongly recommend against using dopamine for treating post-cardiac surgery vasoplegic shock and against using methylene blue for purposes other than a rescue therapy. The authors unanimously and weakly recommend that clinicians consider early addition of a second vasopressor (norepinephrine or vasopressin) if adequate vascular tone cannot be restored by a monotherapy with either norepinephrine or vasopressin and to consider using vasopressin as a first-line vasopressor or to add vasopressin to norepinephrine in cardiac surgical patients with pulmonary hypertension or right-sided heart dysfunction.

Feasibility and pharmacokinetics of caudal blockade in children and adolescents with 30-50 kg of body weight.

BACKGROUND: Caudal blockade, although an important technique of pediatric regional anesthesia, is rarely used in children heavier than 30 kg. This reservation is due to anatomical concerns and lack of pharmacokinetic data. We therefore set out to evaluate, in pediatric patients weighing 30-50 kg, the feasibility of ultrasound-guided caudal blockade and the pharmacokinetics of caudally administered ropivacaine. METHODS: Twenty consecutive children were included. General anesthesia was used to ensure a secured airway. For the caudal punctures, we applied the same clinical standards as in smaller children, administering ropivacaine 3.1 mg·ml-1 for a volume of 1 ml·kg-1 via ultrasound guidance. Pharmacokinetic analysis was based on total plasma ropivacaine levels and included maximum concentration (Cmax ), time to Cmax (tmax ), terminal elimination half-life, area under the concentration-time curve for the 4-h sampling period, apparent total body clearance, and apparent volume of distribution. RESULTS: In all 19 cases of successful puncture, we identified the relevant anatomical structures (sacral cornua, sacral hiatus, dura mater) and verified correct administration of the local anesthetic by visualizing its cranial spread. Surgical blockade was successful in 18 of 20 cases (90%; one puncture was technically not possible and one child received intraoperatively 50 µg fentanyl). The pharmacokinetic profile of the administered ropivacaine 3.1 mg·ml-1 indicated plasma levels within safe ranges in pediatric patients weighing 30-50 kg. CONCLUSIONS: Based on our pharmacodynamic and pharmacokinetic results, we suggest that the body weight of 50 kg it is feasible to perform effective and safe caudal blockade in children up to 50 kg body weight.

A pharmacodynamic evaluation of dexmedetomidine as an additive drug to ropivacaine for peripheral nerve blockade: A randomised, triple-blind, controlled study in volunteers.

BACKGROUND: Previous data have indicated the efficacy of dexmedetomidine as an additive to peripheral regional anaesthesia. There are no pharmacodynamic data regarding the addition of dexmedetomidine to local anaesthetics for perineural administration. OBJECTIVE: The objective of this study is to assess the dose-dependency of dexmedetomidine when injected with ropivacaine for peripheral nerve blockade. DESIGN: A randomised, triple-blind, controlled study in volunteers. SETTING: Department of Clinical Pharmacology, Medical University of Vienna. PARTICIPANTS: Twenty-four volunteers. INTERVENTIONS: All volunteers received an ulnar nerve block with 22.5 mg ropivacaine alone (R), or mixed with 50 (RD50), 100 (RD100) or 150 µg (RD150) dexmedetomidine. MAIN OUTCOME MEASURES: The primary outcome was the duration of complete sensory block to pinprick and time to complete recovery of pinprick. Secondary outcomes included block success and onset time, motor block, haemodynamic parameters and sedation level. RESULTS: There was a significant dose-dependent (P < 0.0001) increase in the mean duration (SD) of sensory block with dexmedetomidine: R: 8.7 (1.5) h, RD50: 16.4 (4.0) h, RD100: 20.4 (2.8) h and group RD150: 21.2 (1.7) h. Sedation was also enhanced in a dose-dependent (P < 0.001) manner. Two volunteers each receiving 150 µg dexmedetomidine had postblock paraesthesia for 72 h. CONCLUSION: Dexmedetomidine mixed with ropivacaine produces a dose-dependent prolongation of sensory block and clinically relevant dose-dependent sedation. Dexmedetomidine 100 µg may represent a balance between efficacy and sedation.

Magnetic resonance imaging analysis of the spread of local anesthetic solution after ultrasound-guided lateral thoracic paravertebral blockade: a volunteer study.

BACKGROUND: This study was designed to examine the spread of local anesthetic (LA) via magnetic resonance imaging after a standardized ultrasound-guided thoracic paravertebral blockade. METHODS: Ten volunteers were enrolled in the study. We performed ultrasound-guided single-shot paravertebral blocks with 20 ml mepivacaine 1% at the thoracic six level at both sides on two consecutive days. After each paravertebral blockade, a magnetic resonance imaging investigation was performed to investigate the three-dimensional spread of the LA. In addition, sensory spread of blockade was evaluated via pinprick testing. RESULTS: The median (interquartile range) cranial and caudal distribution of the LA relative to the thoracic six puncture level was 1.0 (2.5) and 3.0 (0.75) [=4.0 vertebral levels] for the left and 0.5 (1.0) and 3.0 (0.75) [=3.5 vertebral levels] for the right side. Accordingly, the LA distributed more caudally than cranially. The median (interquartile range) number of sensory dermatomes which were affected by the thoracic paravertebral blockade was 9.8 (6.5) for the left and 10.7 (8.8) for the right side. The sensory distribution of thoracic paravertebral blockade was significantly larger compared with the spread of LA. CONCLUSIONS: Although the spread of LA was reproducible, the anesthetic effect was unpredictable, even with a standardized ultrasound-guided technique in volunteers. While it can be assumed that approximately 4 vertebral levels are covered by 20 ml LA, the somatic distribution of the thoracic paravertebral blockade remains unpredictable. In a significant percentage, the LA distributes into the epidural space, prevertebral, or to the contralateral side.

Pediatric regional anesthesia: abdominal wall blocks.

Abdominal wall blocks are an effective regional anesthetic technique to provide sufficient analgesia in abdominal surgery. This article reviews the use of abdominal wall blocks in pediatric regional anesthesia.

Ultrasound-guided upper extremity blocks - tips and tricks to improve the clinical practice.

Brachial plexus blockade in children can be used for a broad spectrum of clinical indications. Nevertheless, these regional anesthetic techniques are still underused in pediatric anesthesia that is mainly because of insufficient descriptions of the particular techniques. Ultrasound guidance enables direct visualization of neuronal and adjacent anatomical structures, the cannula, and the spread of local anesthetic. The most important issue in this context is theoretical background knowledge and intensive training of hand skills. The following review article discusses all relevant aspects of ultrasound-guided brachial plexus blockade.

Perioperative sedation requirements of infants aged 0 to 3 months subjected to lower-body surgery under caudal blockade: a randomized controlled trial.

BACKGROUND: It remains unclear how much sedation is required for subumbilical surgery under caudal blockade, and sedatives may carry a poorly understood risk of late sequelae in infants. We designed a randomized controlled study to evaluate total propofol consumption and perioperative sedation quality with the avoidance of continuous perioperative sedation in infants undergoing surgery under caudal anesthesia. METHODS: Thirty-two infants (age: 0-3 months) were randomized to one of two groups in which perioperative administration of propofol was provided either "as needed" or by continuous infusion (5 mg kg-1 h-1). After induction of anesthesia via a facemask with sevoflurane, a venous access was established and 1 mL kg-1 of ropivacaine 0.35% was injected for caudal anesthesia. Intraoperative stress was assessed by repeated recording comfort behavioral scale scores and heart rates. RESULTS: Significantly (P=0.0001) less propofol was administered in the as-needed group (0.7±1.4 mg/kg) than in the continuous-infusion group (3.0±1.6 mg/kg). This difference was not reflected in different requirements of additional intraoperative sedation (0.5±0.8 mg/kg in 5 versus 0.6±1.0 mg/kg in four cases; P=0.76). CONCLUSIONS: As needed propofol administration offers no disadvantage in terms of intraoperative sedation, but significant dose reductions can be achieved by avoiding continuous propofol infusion.

The First Case of Usutu Virus Neuroinvasive Disease in Austria, 2021.

Usutu virus (USUV) is a mosquito-borne flavivirus closely related to West Nile virus (WNV) that is endemic in many European countries. We report the first case of USUV neuroinvasive disease in Austria and discuss challenges in differentiating USUV from WNV infections in areas where both viruses are endemic.

Management of hypertrophic pylorus stenosis with ultrasound guided single shot epidural anaesthesia--a retrospective analysis of 20 cases.

AIM: To retrospectively describe the performance of ultrasound guided thoracic epidural anaesthesia under sedation for anaesthesia management of open pyloromyotomy. BACKGROUND: Anaesthesia management for hypertrophic pylorus stenosis (HPS) is usually performed under general anaesthesia with tracheal intubation. Only a few publications describe avoidance of tracheal intubation in infants by using spinal or caudal anaesthesia. The present retrospective analysis describes the performance of ultrasound guided thoracic epidural anaesthesia under sedation for anaesthetic management of open pyloromyotomy. METHODS: Twenty consecutive infants scheduled for pyloromyotomy according to the Weber-Ramstedt technique were retrospectively analysed. After sedation with nalbuphine and propofol, an ultrasound guided single shot thoracic epidural anaesthesia was performed with 0.75 ml·kg(-1) ropivacaine 0.475%. Insufficient blockade was defined as increase of HR > 15% from initial value and/or any movements at skin incision. In those cases we were prepared for rapid sequence intubation according to the departmental standard. RESULTS: All pyloromyotomies could be performed under single shot thoracic epidural anaesthesia and sedation. One case of moderate oxygen desaturation was treated with intermittent ventilation via face mask. CONCLUSIONS: Thoracic epidural anaesthesia under sedation for pyloromyotomy has been a useful technique in this retrospective series of infants suffering from HPS. In 1/20 infants short term assisted ventilation via face mask was required. Undisturbed surgery was possible in all cases.

Current concepts and future trends in ultrasound-guided regional anesthesia.

PURPOSE OF REVIEW: Ultrasound guidance for regional anesthesia has gained enormous popularity during the past several years. This review article highlights the importance of acquiring an understanding and knowledge of human anatomy for well tolerated and effective performance of regional anesthesia; includes description of some of the major principles of ultrasound-guided regional anesthesia techniques (adequate identification of neuronal and adjacent anatomical structures along with the procedure needle); use of adequate volumes of local anesthetic and the proper administration of local anesthetic; and discusses economical along with educational aspects of ultrasound-guided regional blocks. RECENT FINDINGS: Recent studies by various authors have indicated that ultrasound-guided regional blocks can be performed by using smaller volumes of local anesthetics. Such findings will further contribute to the safety of regional anesthesia in daily clinical practice. Additional positive economical aspects associated with regional anesthesia have also been described in the recent literature. SUMMARY: With little reservation, it is anticipated that ultrasound-guided regional anesthesia will become the 'GOLD' standard for performance of regional anesthesia. Excellent science and educational concepts will continue to be required with the continued increase in popularity of this exciting specialty of anesthesia.

Ultrasound versus landmark-based technique for ilioinguinal-iliohypogastric nerve blockade in children: the implications on plasma levels of ropivacaine.

BACKGROUND: Ilioinguinal-iliohypogastric nerve blockade (INB) is associated with high plasma concentrations of local anesthetics (LAs) in children. Ultrasonographic guidance enables exact anatomical administration of LA, which may alter plasma levels. Accordingly, we compared plasma levels of ropivacaine after ultrasonographic versus landmark-based INB. METHODS: After induction of general anesthesia, 66 children (8-84 mo) scheduled for inguinal hernia repair received INB with 0.25 mL/kg of ropivacaine 0.5% (1.25 mg/kg) either by a landmark-based (n = 31) or by an ultrasound-guided technique (n = 35). Ropivacaine plasma levels were measured before (0) and 5, 10, 20, and 30 min after the LA injection, using high-performance liquid chromatography. Maximum plasma concentrations (C(max)), time to C(max) (t(max)), the absorption rate constant (k(a)), the speed of rise of the plasma concentration at Time 0 (dC(0)/dt), and area under the curve value (AUC) were determined. RESULTS: The ultrasound-guided technique resulted in higher C(max) (sd), k(a), dC(0)/dt, and AUC values and shorter t(max) compared with the landmark-based technique (C(max): 1.78 [0.62] vs 1.23 [0.70] microg/mL, P < 0.01; k(a): 14.4 [10.7] vs 11.7 [11.4] h(-1), P < 0.05; dC(0)/dt: 0.26 [0.12] vs 0.15 [0.03] microg/mL . min, P < 0.01; AUC: 42.4 [15.9] vs 27.2 [18.1] microg . 30 min/mL, P < 0.001; t(max): 20.4 [8.6] vs 25.3 [7.6] min, P < 0.05). CONCLUSIONS: The pharmacokinetic data indicate faster absorption and higher maximal plasma concentration of LA when ultrasound was used as a guidance technique for INB compared with the landmark-based technique. Thus, a reduction of the volume of LA should be considered when using an ultrasound-guided technique for INB.

Impact of Antiplatelet Therapies on Patients Outcome in Osteosynthetic Surgery of Proximal Femoral Fractures.

BACKGROUND: Proximal femoral fractures should be treated in a timely manner. Affected patients often require antiplatelet therapy (APT) due to cardiovascular diseases. Guidelines recommend 5-7 days APT interruption for elective surgery. Early osteosynthetic surgery of proximal femoral fractures despite of APT should be considered. AIM OF THE STUDY: To evaluate whether early osteosynthetic surgery despite of APT is associated with increased blood loss, complications and mortality. METHODS: Data of patients with proximal femoral fractures, who were treated by osteosynthesis at the Department of Trauma Surgery at the Medical University of Vienna were collected retrospectively. Study groups were formed by time to surgery and APT interruption. The primary endpoint of the study was the perioperative blood loss. Secondary endpoints were complications, 30-day and 1-year mortality, time to surgery, and the total length of hospital stay. RESULTS: The osteosynthetic treatment of proximal femoral fractures despite of APT resulted in a shorter time to surgery (13.8 vs. 66.0 h; p < 0.01). In patients on APT, the TBL (total perioperative blood loss) was higher without need for revision or an increase in the need for packed red blood cells if surgery was performed within 24 h after admission. APT had no significant influence on mortality. Patients who underwent surgery within 24 h after admission had a lower mortality. The complication rate was higher in patients who underwent surgery later than 24 h after admission. CONCLUSIONS: Surgery within 24 h after admission, regardless of APT, resulted in a shorter hospitalization length and was associated with less common complications and a lower mortality.

Ilioinguinal/iliohypogastric blocks in children: where do we administer the local anesthetic without direct visualization?

BACKGROUND: Ultrasonographic observation of peripheral nerve blocks enables direct visualization of the spread of local anesthetic around the targeted nerves. Similarly, ultrasonography may be used to determine the site of local anesthetic placement when landmark-based techniques are used. We performed a study to determine the actual location of local anesthetic when ilioinguinal/iliohypogastric nerve blocks are performed using landmark-based techniques in children in an attempt to explain a failed block. METHODS: After induction of general anesthesia (1 minimum alveolar anesthetic concentration halothane and laryngeal mask airway), 62 children scheduled for inguinal surgery received an ilioinguinal/iliohypogastric nerve block based on standard anatomical landmarks. Ultrasonography was then used to determine the actual location of local anesthetic placement. The anesthesiologist performing the block was blinded to the ultrasonographic investigation. Successful blocks were recorded either when the local anesthetic surrounded the nerves or were based on clinical signs after skin incision. RESULTS: In 14% of the blocks, the local anesthetic was administered correctly around the nerves resulting in successful blocks. In the remaining 86%, the local anesthetic was administered in adjacent anatomical structures (iliac muscle 18%, transverse abdominal muscle 26%, internal oblique abdominal muscle 29%, external oblique abdominal muscle 9%, subcutaneous 2%, and peritoneum 2%), and 45% of these blocks failed. CONCLUSION: Accurate placement of local anesthetic around the ilioinguinal/iliohypogastric nerves in children is seldom possible when landmark-based techniques are used. In the majority of patients, the local anesthetic was inaccurately placed in adjacent anatomical structures with unpredictable block results.

Epidural catheter placement in neonates: sonoanatomy and feasibility of ultrasonographic guidance in term and preterm neonates.

BACKGROUND: We report the first prospective sonoanatomic study in neonates with the aim to perform ultrasonographic-guided epidural catheter placement in this age group. METHOD: One hundred forty-five neonates with a body weight < or =4 kg (0.53-4 kg) were included in this prospective study. The study was divided into 3 consecutive parts. In the first part, the neuraxial sonoanatomy of 60 neonates was evaluated. In the second part, 50 neonates scheduled for major abdominal surgery were enrolled. In this part, the depth of the ligamentum flavum measured with ultrasound was matched up to the depth evaluated clinically with the loss-of-resistance technique. In the third part, ultrasonographic epidural catheter placement was performed in 35 neonates weighing between 620 g and 4 kg. RESULTS: The ligamentum flavum, the dura mater, and the termination of the spinal cord could be identified in all patients. The first part showed a good correlation between body weight and depth of the ligamentum flavum. The median termination of the spinal cord corresponded to vertebral level L2. The second part confirmed a good correlation between depth of the ligamentum flavum evaluated clinically and the depth predicted with ultrasound. Finally, real-time ultrasound-guided epidural placement was possible in all 35 neonates. CONCLUSION: Ultrasound examination of the spinal cord anatomy provides valuable information for epidural catheter placement in neonates. Ultrasonography enables a real-time identification of the tip of the needle within the epidural space and a visualization of the spread of local anesthetic in these patients.

Club cell protein 16 and cytokeratin fragment 21-1 as early predictors of pulmonary complications in polytraumatized patients with severe chest trauma.

BACKGROUND: Acute respiratory distress syndrome (ARDS) and pneumonia have a great impact on the treatment regimen of polytraumatized patients with severe chest trauma. The objective of our study was to determine whether biomarker levels assessed shortly after multiple trauma may predict the occurrence of these conditions. METHODS AND FINDINGS: Our patient population included 71 men and 30 women (mean age, 40.3 ± 15.8 years) with an Injury Severity Score that ranged from 17 to 59 and an Abbreviated Injury Scale Thorax of at least 3. They were admitted to our level I trauma center within one post-traumatic hour and survived for at least 24 hours after the trauma occurred. Thirty-five patients developed ARDS, 30 patients pneumonia and 21 patients both. Five individuals died during hospitalization. The levels of five selected biomarkers, which were identified by a literature search, were assessed at admission (initial levels) and on day 2 after trauma. We performed comparisons of medians, logistic regression analyses and receiver operating characteristic analyses for initial and day-2 levels of each biomarker. With regard to ARDS, initial levels of cytokeratin fragment 21-1, the soluble fragment of cytokeratin 19 (CYFRA21-1) and of the club cell protein 16 (CC16) provided significant results in each statistical analysis. With regard to pneumonia, each statistical analysis supplied significant results for both initial and day-2 levels of CYFRA21-1 and CC16. Consistently, initial CYFRA21-1 levels were identified as the most promising predictor of ARDS, whereas day-2 CC16 levels have to be considered as most appropriate for predicting pneumonia. CONCLUSIONS: CYFRA21-1 levels exceeding cut-off value of 1.85 ng/ml and 2.49 ng/ml in the serum shortly after multiple injury occurred may identify polytraumatized patients at risk for ARDS and pneumonia, respectively. However, CC16 levels exceeding 30.51 ng/ml on day 2 may allow a firmer diagnosis for the development of pneumonia.

The clinical benefit of a follow-up thoracic computed tomography scan regarding parenchymal lung injury and acute respiratory distress syndrome in polytraumatized patients.

PURPOSE: To evaluate the increase of parenchymal lung injury (PLI) volume between the initial and a follow-up computed tomography (CT) scan and to ascertain which of the 2 scans was more appropriate to predict acute respiratory distress syndrome (ARDS). MATERIAL AND METHODS: From 2011 to 2015, polytraumatized patients (≥18 years; ISS ≥ 16) directly admitted to our level I trauma center were included in our prospective study if a follow-up CT scan was possible 24 to 48 hours after the trauma. The PLI volume was measured using volumetric analysis. Statistical calculations were performed to identify patients at risk for ARDS. RESULTS: One hundred thirty patients (mean age, 41.3 years; mean ISS, 31.9) met the inclusion criteria. Median relative PLI volume was higher in the follow-up than in the initial CTs (9.65% vs 4.84%; P = .001). The ARDS developed in 42 patients (32.3%). Their initial PLI volume was higher compared with those without ARDS (11.23% vs 2.14%; P < .0001). The ARDS incidence increased with increasing initial PLI volume. Receiver operating characteristic statistics identified initial (area under the curve = 0.753) and follow-up relative PLI volume as a predictor for ARDS (area under the curve = 0.725). CONCLUSIONS: The CT scans performed directly after admission are sufficient to define patients at risk for ARDS. Therefore, solely the incidence of PLI does not justify a routine follow-up CT scan.