The safety and utility of the semi-sitting position for clipping of posterior circulation aneurysms.

BACKGROUND: The semi-sitting position offers advantages for surgeries in the posterior cranial fossa. However, data on its safety and effectiveness for clipping aneurysms in the posterior cerebral circulation are limited. This retrospective cohort study evaluates the safety and effectiveness of using the semi-sitting position for these surgeries. METHODS: We conducted a retrospective study of 17 patients with posterior cerebral circulation aneurysms who underwent surgical clipping in the semi-sitting position in the Department of Neurosurgery at Hannover Medical School over a 10-year period. RESULTS: The mean age at surgery was 62 years (range, 31 to 75). Fourteen patients were admitted with subarachnoid hemorrhage and 3 patients had incidental aneurysmas. Fifteen patients had PICA aneurysms, and two had aneurysms of the vertebral artery and the superior cerebellar artery, respectively. The median diameter of the aneurysms was 5 mm (range 3-17 mm). Intraoperative venous air embolism (VAE) occurred in 4 patients, without affecting the surgical or clinical course. VAE was associated with a mild decrease of EtCO2 levels in 3 patients and in 2 patients a decrease of blood pressure occurred which was managed effectively. Surgical procedures proceeded as planned in all instances. There were no complications secondary to VAE. Two patients died secondary to respiratory problems (not related to VAE), and one patient was lost to follow-up. Eleven of fourteen patients were partially or completely independent (Barthel index between 60 and 100) at a median follow-up duration of 13.5 months (range, 3-103 months). CONCLUSION: The semi-sitting position is a safe and effective technique for the surgical clipping of aneurysms in the posterior cerebral circulation. The incidence of VAE is comparable to that seen in tumor surgery. However, it is crucial for the surgical and anesthesiological team to be familiar with potential complications and to react immediately in case of an occurrence of VAE.

Resection of posterior fossa tumors in the semi-sitting position in children younger than 4 years of age.

PURPOSE: The semi-sitting position for resection of posterior fossa tumors is a matter of ongoing debate. Here we report about our experience with this approach in children younger than 4 years of age. METHODS: We retrospectively analyzed data of children younger than 4 years of age operated on in our institution in the semi-sitting position over a 15-year period. Patients were intraoperatively monitored for venous air embolism (VAE) by transthoracic Doppler (TTD) or transesophageal echocardiography (TEE). The severity of VAE was classified according to the Tübingen grading scale. Intraoperative incidents of VAE were recorded and the patients' course was followed postoperatively with a special focus on possible complications. RESULTS: Twenty-four children (18 boys, 6 girls) were operated on in the semi-sitting position (26 operations). Mean age was 2.2 years (± 1.0), range between 0.4 and 3.9 years. External ventricular drains were inserted in 18 children with hydrocephalus preoperatively. VAE was detected in 6 instances during surgery (6/26 (23.1%)). In 3 patients with grade 1 VAE, no additional treatment was necessary. In one patient with grade 2 VAE, intracardiac air suction via the central venous catheter was performed, and in two patients with grade 4 VAE, additional cathecholamine-infusion was administered. No major intraoperative complications occurred. Postoperative CT images showed pneumocephalus in all children. In two children, small asymptomatic impression skull fractures at the site of the Mayfield pin occurred. Revision surgery was necessary in one child with a suboccipital CSF fistula. CONCLUSION: The semi-sitting position for resection of tumors in the posterior fossa in children younger than 4 years of age can be safely performed in experienced centers taking special caution to detect and treat potential complications in an interdisciplinary setting.

Surgical treatment of spondylodiscitis in critically ill septic patients.

PURPOSE: Surgical procedures in critically ill patients with spondylodiscitis are challenging and there are several controversies. Here, we present our experience with offering surgical intervention early in critically ill septic patients with spondylodiscitis. METHOD: After we introduced a new treatment paradigm offering early but limited surgery, eight patients with spondylodiscitis complicated by severe sepsis and multiple organ failure underwent urgent surgical treatment over a 10-year period. Outcome was assessed according to the Barthel index at 12-month follow-up and at the last available follow-up (mean 89 months). RESULTS: There were 7 men and 1 woman, with a mean age of 62 years. The preoperative ASA score was 5 in 2 patients, and 4 in 6 patients. Six of them presented with high-grade paresis, and in all of them, spondylodiscitis with intraspinal and/or paravertebral abscesses was evident in MR imaging studies. All patients underwent early surgery (within 24 h after admission). The median time in intensive care was 21 days. Out of the eight patients, seven survived. One year after surgery, five patients had a good outcome (Barthel index: 100 (1); 80 (3); and 70 (1)). At the last follow-up (mean 89 months), 4 patients had a good functional outcome (Barthel index between 60 and 80). CONCLUSION: Early surgical treatment in critically ill patients with spondylodiscitis and sepsis may result in rapid control of infection and can provide favorable long-term outcome. A general strategy of performing only limited surgery is a valid option in such patients who have a relatively high risk for surgery.

Routine postoperative admission to the neurocritical intensive care unit after microvascular decompression: necessary or can it be abandoned?

Postoperative neurocritical intensive care unit (NICU) admission of patients who underwent craniotomy for close observation is common practice. In this study, we performed a comparative analysis to determine if there is a real need for NICU admission after microvascular decompression (MVD) for cranial nerve disorders or whether it may be abandoned. The present study evaluates a consecutive series of 236 MVD surgeries performed for treatment of trigeminal neuralgia (213), hemifacial spasm (17), vagoglossopharyngeal neuralgia (2), paroxysmal vertigo (2), and pulsatile tinnitus (2). All patients were operated by the senior surgeon according to a standard protocol over a period of 12 years. Patients were admitted routinely to NICU during the first phase of the study (phase I), while in the second phase (phase II), only patients with specific indications would go to NICU. While 105 patients (44%) were admitted to NICU postoperatively (phase I), 131 patients (56%) returned to the ward after a short stay in a postanaesthesia care unit (PACU) (phase II). Specific indications for NICU admission in phase I were pneumothorax secondary to central venous catheter insertion (4 patients), AV block during surgery, low blood oxygen levels after extubation, and postoperative dysphagia and dysphonia (1 patient, respectively). There were no significant differences in the distribution of ASA scores or the presence of cardiac and pulmonary comorbidities like congestive heart failure, arterial hypertension, or chronic obstructive pulmonary disease between groups. There were no secondary referrals from PACU to NICU. Our study shows that routine admission of patients after eventless MVD to NICU does not provide additional value. NICU admission can be restricted to patients with specific indications. When MVD surgery is performed in experienced hands according to a standard anaesthesia protocol, clinical observation on a neurosurgical ward is sufficient to monitor the postoperative course. Such a policy results in substantial savings of costs and human resources.

[Complications and success rates of subclavian vein catheterization depending on experience]. / Komplikationen und Erfolgsraten des Vena-subclavia-Katheters in Abhängigkeit der Erfahrung.

BACKGROUND: The infraclavicular puncture of the subclavian vein is a standard procedure for anesthetists. Meanwhile the literature and recommendations are clear and the use of real-time ultrasound guidance is the standard procedure; however, anesthetists will always get into special circumstances were they have to use the landmark technique, so this competence must be preserved. Feared complications of infraclavicular subclavian vein puncture are pneumothorax and arterial puncture. Up to now there is no clear learning curve for the infraclavicular subclavian vein puncture in the landmark technique performed by anesthetists. OBJECTIVE: The aim of this study was to examine the influence of the puncture experience on the success rate and mechanical complications, such as pneumothorax and arterial puncture in patients who received an infraclavicular subclavian vein puncture with the landmark technique. Three levels of experience were defined for comparison: inexperienced 0-20 punctures, moderately experienced 21-50 and experienced over 50 punctures. MATERIAL AND METHODS: Post hoc analysis of a previously published noninferiority study to examine the influence of ventilation on the pneumothorax rate in the subclavian vein puncture using the landmark technique. This analysis included 1021 anesthetized patients who were included in the original study between August 2014 and October 2017. Demographic data as well as the number of puncture attempts, puncture success, the overall rate of mechanical complications, pneumothorax rate and arterial puncture rates were calculated. RESULTS: The overall rate of mechanical complications (pneumothorax + arterial puncture) was significantly higher in the inexperienced group (0-21) compared to the experienced group (>50, 15% vs. 8.5%, respectively, p = 0.023). This resulted in an odds ratio of 0.52 (confidence interval, CI: 0.32-0.85, p = 0.027). Likewise, the rate of puncture attempts in the group of inexperienced (0-20) with 1.85 ± 1.12 was significantly higher than in the group of experienced (>50, 1.58 ± 0.99, p = 0.004) and resulted in an odds ratio of 0.59 (CI: 0.31-0.96, p = 0.028). Although the puncture attempts of the moderately experienced (21-50) compared to the inexperienced (0-20) was not significant lower, we found an odds ratio of 0.69 (CI: 0.48-0.99, p = 0.042). The rate of successful puncture was 95.1% in the experienced group versus 89.3% in the inexperienced group (p = 0.001), which resulted in an odds ratio of 2.35 (CI: 1.28-4.31, p = 0.018). When viewed individually, no significant differences were found for pneumothorax and arterial puncture. CONCLUSION: In this post hoc analysis of the puncture of the subclavian vein using the landmark technique, we found a significant reduction of puncture attempts and overall mechanical complications. At least 50 punctures seem to be necessary to achieve the end of the learning curve; however, the landmark technique should only be used under special circumstances, when real-time ultrasound is not available. Anesthetists who want to complete their repertoire and learn the landmark technique should always perform a static ultrasound examination before starting the puncture in order to reduce complications due to anatomical variations or thrombosis.

Preoperative Recipient Parameters Allow Early Estimation of Postoperative Outcome and Intraoperative Transfusion Requirements in Liver Transplantation.

CONTEXT: Liver transplantation is a complex intervention, and early anticipation of personnel and logistic requirements is of great importance. Early identification of high-risk patients could prove useful. We therefore evaluated prognostic values of recipient parameters commonly available in the early preoperative stage regarding postoperative 30- and 90-day outcomes and intraoperative transfusion requirements in liver transplantation. DESIGN, SETTING, AND PARTICIPANTS: All adult patients undergoing first liver transplantation at Hannover Medical School between January 2005 and December 2010 were included in this retrospective study. Demographic, clinical, and laboratory data as well as clinical courses were recorded. Prognostic values regarding 30- and 90-day outcomes were evaluated by uni- and multivariate statistical tests. Identified risk parameters were used to calculate risk scores. RESULTS: There were 426 patients (40.4% female) included with a mean age of 48.6 (11.9) years. Absolute 30-day mortality rate was 9.9%, and absolute 90-day mortality rate was 13.4%. Preoperative leukocyte count >5200/µL, platelet count <91 000/µL, and creatinine values ≥77 µmol/L were relevant risk factors for both observation periods ( P < .05, respectively). A score based on these factors significantly differentiated between groups of varying postoperative outcomes and intraoperative transfusion requirements ( P < .05, respectively). CONCLUSION: A score based on preoperative creatinine, leukocyte, and platelet values allowed early estimation of postoperative 30- and 90-day outcomes and intraoperative transfusion requirements in liver transplantation. Results might help to improve timely logistic and personal strategies.

Comparative characterization of single cell activity in the globus pallidus internus of patients with dystonia or Tourette syndrome.

Altered processing in the basal ganglia has been described both in dystonia and Tourette's syndrome (TS). Deep brain stimulation (DBS) of the globus pallidus internus (GPi) has become a recognized treatment for dystonia and has been used successfully to alleviate tics in TS. This study evaluates possible differences of GPi linear and nonlinear neuronal discharge characteristics between patients with dystonia and TS. Nine patients with primary dystonia and six patients with TS were studied during functional stereotactic neurosurgical operations for implantation of DBS electrodes under general anesthesia. Six patients with primary dystonia under local anesthesia served as non-anesthetized controls. Single-unit activity recordings in the GPi were obtained during routine microelectrode recording and mapping to delineate nuclear borders and to identify the sensorimotor subregions. Anesthesia profoundly decreased neuronal activity in patients with dystonia. Dystonia patients showed marginally higher mean firing rates in the GPi compared to TS patients (P = 0.06). Although the average total number of bursts and the mean peak frequency in bursts did not differ between groups, the mean spikes in bursts were higher in dystonia patients (P < 0.05). Nonlinear time series analysis metrics, measured as complexity of Lempel-Ziv and maximum approximate entropy, revealed higher randomness in TS compared to dystonia patients (P < 0.05). The percentage of oscillating neurons in spike trains was higher in dystonia compared to TS (P < 0.05). Our data provide evidence for differences of the neuronal dynamic complexity, randomness and oscillatory modulation of spike trains in the GPi between dystonia and TS. Such differences, although subtle, might contribute to the specific clinical phenomenology secondary to disordered neuronal basal ganglia processing.

Changes of blood endocannabinoids during anaesthesia: a special case for fatty acid amide hydrolase inhibition by propofol?

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: • Available data from animal studies suggest that the narcotic drug propofol interacts with the endocannabinoid system. Inhibition of enzymatic degradation of anandamide could explain some of the characteristics of propofol. Direct measurements have not been reported yet in humans. WHAT THIS STUDY ADDS: • Propofol does not change the time course of anandamide plasma concentrations during anaesthesia. Furthermore, propofol does not inhibit fatty acid amide hydrolase activity ex vivo or in vitro. Thus, specific characteristics of the narcotic drug propofol cannot be explained by peripheral inhibition of anandamide degradation in humans. AIMS: The aim of our study was to describe the time course of endocannabinoids during different anaesthesia protocols in more detail, and to challenge the hypothesis that propofol acts as a FAAH inhibitor. METHODS: Endocannabinoids were measured during the first hour of anaesthesia in 14 women and 14 men undergoing general anaesthesia with propofol and in 14 women and 14 men receiving thiopental/sevoflurane. We also incubated whole human blood samples ex vivo with propofol and the known FAAH inhibitor oloxa and determined FAAH enzyme kinetics. RESULTS: Plasma anandamide decreased similarly with propofol and thiopental/sevoflurane anaesthesia, and reached a nadir after 10 min. Areas under the curve for anandamide (mean and 95% CI) were 53.3 (47.4, 59.2) nmol l(-1) 60 min with propofol and 48.5 (43.1, 53.8) nmol l(-1) 60 min with thiopental/sevoflurane (P= NS). Anandamide and propofol plasma concentrations were not correlated at any time point. Ex vivo FAAH activity was not inhibited by propofol. Enzyme kinetics (mean ± SD) of recombinant human FAAH were K(m) = 16.9 ± 8.8 µmol l(-1) and V(max) = 44.6 ± 15.8 nmol mg(-1) min(-1) FAAH without, and K(m) = 16.6 ± 4.0 µmol l(-1) and V(max) = 44.0 ± 7.6 nmol mg( 1 ) min(-1) FAAH with 50 µmol l(-1) propofol (P= NS for both). CONCLUSIONS: Our findings challenge the idea that propofol anaesthesia and also propofol addiction are directly mediated by FAAH inhibition, but we cannot exclude other indirect actions on cannabinoid receptors.

Thyroid gland rupture: a rare case of respiratory distress.

BACKGROUND: Rupture of a normal thyroid gland after blunt cervical trauma is a rare case of airway compression. This case report describes the case of a 79-year-old woman who developed severe respiratory distress after a bicycle crash. CASE REPORT: Presenting about 2 h after the crash, the patient noted cervical swelling and increasing dyspnea. The diagnosis of thyroid gland rupture was made with a combination of computed tomography scan, cervical radiography, and bronchoscopy. Invasive airway management was required in the first few hours after the crash. The patient underwent a left hemithyroidectomy, and recovered without complications. CONCLUSION: This case report highlights the fact that thyroid gland rupture can be a threatening complication of blunt cervical trauma.

Pre- and intraoperative cerebral near-infrared spectroscopy and postoperative delirium: Results of a prospective cross-sectional trial.

Postoperative delirium (PODE) is a serious complication that can occur during the first few days after surgery. A number of causes can make delirium more likely; one factor to consider is hypoxia during anesthesia. In this study, the pre- and intraoperative cerebral regional oxygen saturation (rSO2) as measured by near-infrared spectroscopy (NIRS) was to be examined with regard to an association with the occurrence of PODE in patients undergoing major abdominal procedures. Data from 80 patients (33 women, 47 men) was examined. The mean age was 66.31 ± 10.55 years (between 42 and 84 years). Thirteen patients developed PODE. The preoperative rSO2 values (P = .10) and the rSO2 values during the steady state of anesthesia (P = .06) tended to be lower in the delirium group than in the non-delirium group. There was a significant correlation between the preoperative rSO2 and the preoperative hemoglobin values (P < .001). The variance of rSO2 during the steady state of anesthesia was significantly greater in the delirium group compared to the non-delirium group (P = .03). In two patients from the delirium group, rSO2 dropped below 50%; they also had a minimum mean arterial pressure below 50 mm Hg, which could have disturbed cerebral autoregulation. The duration of rSO2 decreases (>10%, >15%, >20%) and increases (>10%) compared to the preoperative values was not significantly different between patients with and without PODE. The results suggest that NIRS could be a useful monitoring method for patients undergoing abdominal surgical procedures, on the one hand to recognize patients with low pre- or intraoperative rSO2 values, and on the other hand to detect changes in rSO2 values during anesthesia.

Intraoperative monitoring parameters and postoperative delirium: Results of a prospective cross-sectional trial.

ABSTRACT: Postoperative delirium (PODE) can be associated with severe clinical complications; therefore, preventive measures are important. The objective of this trial was to elucidate whether haemodynamic or electroencephalographic (EEG) monitoring parameters during general anaesthesia or sevoflurane dosage correlate with the incidence of PODE. In addition, sevoflurane dosages and EEG stages during the steady state of anaesthesia were analyzed in patients of different ages.Eighty adult patients undergoing elective abdominal surgery received anaesthesia with sevoflurane and sufentanil according to the clinical routine. Anaesthesiologists were blinded to the EEG. Haemodynamic parameters, EEG parameters, sevoflurane dosage, and occurrence of PODE were analyzed.Thirteen patients (4 out of 33 women, 9 out of 47 men) developed PODE. Patients with PODE had a greater mean arterial pressure (MAP) variance (267.26 (139.40) vs 192.56 (99.64) mmHg2, P = .04), had a longer duration of EEG burst suppression or suppression (27.09 (45.32) vs 5.23 (10.80) minutes, P = .03), and received higher minimum alveolar sevoflurane concentrations (MAC) (1.22 (0.22) vs 1.09 (0.17), P = .03) than patients without PODE. MAC values were associated with wide ranges of EEG index values representing different levels of hypnosis.The results suggest that, in order to prevent PODE, a great variance of MAP, higher doses of sevoflurane, and deep levels of anaesthesia should be avoided. Titrating sevoflurane according to end-tidal gas monitoring and vital signs can lead to unnecessarily deep or light hypnosis. Intraoperative EEG monitoring may help to prevent PODE.

Analysis of risk factors for venous air embolism in the semisitting position and its impact on outcome in a consecutive series of 740 patients.

OBJECTIVE: Routine use of the semisitting position, which offers several advantages, remains a matter of debate. Venous air embolism (VAE) is a potentially serious complication associated with the semisitting position. In this study, the authors aimed to investigate the safety of the semisitting position by analyzing data over a 20-year period. METHODS: The incidence of VAE and its perioperative management were analyzed retrospectively in a consecutive series of 740 patients who underwent surgery between 1996 and 2016. The occurrence of VAE was defined by detection of bubbles on transthoracic Doppler echocardiography (TTDE) or transesophageal echocardiography (TEE) studies, a decrease of end-tidal CO2 (ETCO2) by 4 mm Hg or more, and/or an unexplained drop in systolic arterial blood pressure (≥ 10 mm Hg). From 1996 until 2013 TTDE was used, and from 2013 on TEE was used. The possible risk factors for VAE and its impact on surgical performance were analyzed. RESULTS: There were 404 women and 336 men with a mean age at surgery of 49 years (range 1-87 years). Surgery was performed for infratentorial lesions in 709 patients (95.8%), supratentorial lesions in 17 (2.3%), and cervical lesions in 14 (1.9%). The most frequent pathology was vestibular schwannoma. TEE had a higher sensitivity than TTDE. While TEE detected VAE in 40.5% of patients, TTDE had a detection rate of 11.8%. Overall, VAE was detected in 119 patients (16.1%) intraoperatively. In all of these patients, VAE was apparent on TTDE or TEE. Of those, 23 patients also had a decrease of ETCO2, 18 had a drop in blood pressure, and 23 had combined decreases in ETCO2 and blood pressure. VAE was detected in 24% of patients during craniotomy before opening the dura mater, in 67% during tumor resection, and in 9% during wound closure. No risk factors were identified for the occurrence of VAE. Two patients had serious complications due to VAE. Surgical performance in vestibular schwannoma surgery was not affected by the presence of VAE. CONCLUSIONS: This study shows that the semisitting position is overall safe and that VAE can be managed effectively. Persistent morbidity is very rare. The authors suggest that the semisitting position should continue to have a place in the standard armamentarium of neurological surgery.

Intracranial emergencies during pregnancy requiring urgent neurosurgical treatment.

OBJECTIVE: Despite contemporary diagnostic and therapeutic techniques intracranial emergencies in the obstetric setting pose still a major challenge for the clinicians. There are limited guidelines and differing ethical views. Multidisciplinary teams are needed to support the pregnant woman in a way that she can deliver a viable and healthy child. The aim of the present study was to scrutinize the management of intracranial emergencies during pregnancy which needed urgent neurosurgical treatment. PATIENTS AND METHODS: Data of all pregnant women who presented with newly diagnosed intracranial pathologies and neurological symptoms caused by these pathologies in an emergency setting were collected over a 10-year period (2008-2018). Patient characteristics including maternal age, gestational age, and preoperative work-up of both mother and fetus were recorded. Furthermore, the surgical treatment, mode of delivery, and neonatal and maternal outcomes were analysed. RESULTS: The mean maternal age was 32.7 years and most patients were in their third trimester. There was one twin pregnancy (total of 12 fetuses). Five out of eleven pregnant women suffered from intracerebral haemorrhage (epidural haematoma (1), arteriovenous malformation (1), subarachnoid haemorrhage (2) and intracerebral haemorrhage (1)) and the other six patients had intracranial neoplasms (primary meningeal sarcoma (1), trigeminal schwannoma (1), anaplastic astrocytoma (2), glioblastoma (1) and sphenoid wing meningioma (1)).Neurosurgical procedures were performed via craniotomies in eight patients. A stereotactic biopsy via a frontal burr hole was achieved one patient. The two other patients with subarachnoid haemorrhage due to rupture of PICA aneurysms were treated with coil embolization. Depending on the gestational age and the clinical condition of the pregnant women it was decided to perform an emergency Caesarean section prior to further therapeutic measures in seven patients. Two out of 12 fetuses were unviable. Six women survived, while five women succumbed to the intracranial pathology. CONCLUSION: The individualized treatment approach in this peculiar obstetric scenario needs to consider various issues such as the clinical condition of the pregnant woman, prognosis of the disease, gestational age and the status of the pregnancy. The primary concern in this context must be the mother`s health and safety. Caesarean section is the primary mode of delivery in most cases. While contemporary care can insure survival for the majority of infants, maternal mortality still poses an extraordinary challenge. Interdisciplinary consulting of the patient and/or her family is necessary to develop a treatment strategy for both the expectant woman and her offspring.

Spinal Emergency Surgery During Pregnancy: Contemporary Strategies and Outcome.

BACKGROUND: Low back pain is a common complaint during pregnancy. However, spinal pathologies, which manifest with severe pain, radiculopathy, and acute neurologic deficits because of disk herniation or mass lesions require special attention. Here, we present our interdisciplinary experience in the surgical management of spinal emergencies during pregnancy. METHODS: The data of pregnant women who underwent surgery for spinal pathologies over a 10-year period were collected. Patient-related characteristics such as maternal age, gestational age, preoperative workup, signs and symptoms of mothers, and diagnostic procedures were evaluated. After an interdisciplinary conference, individualized treatment plans regarding available options were developed. Fetal Doppler and cardiotocography were obtained before and after surgery. RESULTS: Nine pregnant women presented with spinal disorders and underwent spinal emergency surgery within the study period. The mean maternal age was 32.2 years. Six women presented with lumbar disk herniations manifesting as severe sciatica or foot drop and 3 patients had thoracic mass lesions resulting in cauda equine syndrome and/or ataxia. The mean gestational age at the time of presentation was 26.5 weeks. Caesarean sections were performed in 3 women prior to the neurosurgical procedure, whereas the pregnancies were maintained in the 6 other patients. Eight infants who were healthy at birth had an unremarkable development. CONCLUSIONS: Surgery for spinal emergencies in pregnancy can be performed safely according to individual treatment plans developed by an interdisciplinary team taking into account the expectant mother's decision. Maintenance of pregnancy is possible and feasible in most patients.

Reduced post-operative neutrophil activation in liver transplant recipients suffering from post-hepatitic cirrhosis.

BACKGROUND: It has been supposed that liver transplant recipients with hepatitis C virus infection have a higher incidence of infectious complications after transplantation. This study was designed to investigate whether neutrophil function is immediately affected by liver transplantation. METHODS: Biochemical values, plasma levels of myeloperoxidase (MPO), hydrogen peroxide production of neutrophils and neutrophil-platelet complexes were analyzed in 32 patients who underwent liver transplantation and 20 healthy volunteers. RESULTS: MPO levels were significantly increased 24 h after reperfusion. In post-hepatitic patients levels were significantly lower three d up to one wk post-transplant than in patients due to other liver diseases. One wk post-operatively the respiratory burst activity following N-formyl-methionyl-leucylphenylalanine (fMLP) or (tumor necrosis factor-alpha) TNF-alpha/fMLP stimulation was depressed in post-hepatitic recipients. Respiratory burst stimulated with phorbol 12-myristate 13-acetate in these patients was increased one wk after transplantation. One d after transplantation the neutrophil-platelet complexes decreased significantly throughout the post-operative period. CONCLUSIONS: The results of this study suggest a reduced post-operative neutrophil activation in liver transplant recipients suffering from post-hepatitic cirrhosis compared to cirrhosis due to other causes. We hypothesized that neutrophil dysfunction in those patients depends on the underlying disease with an increased susceptibility to bacterial or fungal infections.

Mannitol and the Combination of Mannitol and Gelatin Impair Whole Blood Coagulation and the Platelet Function In Vitro.

OBJECTIVE: Mannitol 20% and succinylated gelatin 4% are routinely used in neurosurgical procedures. The aim of this in vitro study was to explore the influence of both agents on blood coagulation and platelet function. METHODS: Blood from 21 healthy volunteers was obtained and then diluted so as to form five groups: (1) 7% dilution with mannitol; (2) 10% dilution with gelatin; (3) 17% dilution with isotonic balanced electrolyte solution; (4) 17% dilution with mannitol+gelatin; and (5) undiluted blood. The extrinsic thrombelastometry (EXTEM) and fibrin thrombelastometry (FIBTEM) tests were examined by rotational thrombelastometry via ROTEM®, and thrombocyte aggregometry with the aspirin inhibiting- (ASPI), adenosine diphosphate- (ADP), and thrombin-activating protein (TRAP) tests performed by Multiplate. RESULTS: In the EXTEM test clot formation time, the alpha angle, and maximum clot firmness were significantly reduced by mannitol and the combination of mannitol with gelatin. The platelet function tested in the ADP test was also significantly reduced with this combination. CONCLUSION: In this in vitro study, clinically relevant dilutions of mannitol and gelatin showed a significant inhibition of whole blood coagulation and the platelet function, which could be detrimental in neurosurgical settings.

Use of Rotational Thromboelastometry in Liver Transplantation Is Associated With Reduced Transfusion Requirements.

OBJECTIVES: Increased transfusion requirements in liver transplantation have been reported to be associated with worsened outcomes, more frequent reinterventions, and higher expenses. Anesthesiologists might counteract this through improved coagulation management. We evaluated the effects of rotational thromboelastometry on transfusion and coagulation product requirements and on outcome measurements. MATERIALS AND METHODS: Patients who were 14 years or older and who were undergoing liver transplant at Hannover Medical School between January 2005 and December 2009 were included in this retrospective analysis. Demographic, clinical, and laboratory data, use of rotational thromboelastometry, intraoperative need for blood or coagulation products and antifibrinolytic substances, and clinical course were recorded. Correlations were examined using appropriate statistical tests. RESULTS: Our study included 413 patients. Use of rotational thromboelastometry was associated with less frequent intraoperative administration of red blood cell concentrates, fresh frozen plasma, platelet concentrates, prothrombin complex concentrates, and antithrombin concentrates (all P < .05). In addition, univariate and multivariate tests showed that rotational thromboelastometry was correlated with decreased need for red blood cell concentrates and fresh frozen plasma (all P < .05). Intraoperative administration rates of antifibrinolytic substances and fibrinogen concentrate were significantly increased in patients who received rotational thromboelastometry monitoring (both P < .05). However, use of rotational thromboelastometry was not associated with massive transfusion rates (> 10 units vs less), clinical outcome, or length of stay in the intensive care unit (all P > .05). CONCLUSIONS: Use of rotational thromboelastometry during liver transplant may reduce the need for intraoperative transfusion and coagulation products. Relevant effects of rotational thromboelastometry on patient outcomes or lengths of stay in the intensive care unit could not be ascertained. However, readjustment of therapeutic thresholds may improve the clinical impact.

Renal transplantation normalized hydrogen peroxide production of neutrophils within the first day.

BACKGROUND: Hemodialysis patients are in a state of oxidant stress. In renal transplantation reactive oxygen species (ROS) are considered to be important factors of ischemia-reperfusion injury. Neutrophils produce ROS as part of the host defense against invading bacteria. This study was designed to investigate whether neutrophil function in hemodialysis patients is immediately affected by renal transplantation. METHODS: We evaluated the neutrophil respiratory burst and phagocytic activity in renal transplant patients with living-related donor (LRD) and cadaveric donor (CAD) grafts using flow cytometry techniques. Twenty patients (LRD = 6, CAD = 14) and 20 healthy volunteers were included in the study. Venous blood samples were drawn before anesthesia, 5 min before reperfusion, 1 h and 1, 3 and 7 days after reperfusion. RESULTS: Before surgery, a significant increase in hydrogen peroxide production in neutrophils was seen for both renal transplantation groups compared to healthy subjects. Within 24 h after reperfusion hydrogen peroxide production almost decreased to normal values. The phagocytic capacity of neutrophils was continuously depressed. There were no differences between the CAD and LRD groups. CONCLUSIONS: We found that the enhanced respiratory burst activity of patients with chronic renal failure decreased to normal values within 1 day following renal transplantation. Our results suggest that reduced respiratory burst activity resulting in a diminished risk of tissue damage by the uncontrolled production of ROS.

Ethanol-induced malfunction of neutrophils respiratory burst on patients suffering from alcohol dependence.

BACKGROUND: Polymorphonuclear, neutrophil granulocytes (PMN) play a major role in the control of infections, and people who abuse alcohol are susceptible to infections. Resistance against infections ensues intracellularly following initial phagocytosis of microorganisms with the oxygen-dependent respiratory burst, the key enzyme of which is the respiratory burst oxidase, whereby oxygen radicals are produced for microbial destruction. To date there is insufficient information available in connection with the process of impaired defence against infection in patients suffering from alcohol dependence. Therefore, our investigation was carried out to determine the influence of alcohol exposition on the formation of oxygen radicals and the respiratory burst. METHODS: 4.5 ml of whole blood was taken from 10 healthy adults and 10 patients suffering from alcohol dependence. An additional 3.5 ml of whole blood was taken from the alcoholic patients for determination of the blood alcohol concentration. The respiratory burst of PMN was tested using the Four-Colour-Continuous Flow Cytometer. Each experimental procedure consisted of 4 test samples [negative controls, Escherichia coli, FMLP-supplement (N-formyl-l-methionyl-l-leucyl-l-phenylalanin), PMA-supplement (phorbol-12-myristate-13-acetate)]. Differing concentrations of ethanol were also introduced to each of the tests performed (0.20 to 4.00 g/l). RESULTS: Ethanol revealed a marked decrease of burst activity in those patients suffering from alcoholism with increased alcohol concentration. A dependence between the burst activity and the ethanol concentration was seen to be statistically significant. This effect was only evident after stimulation with E. coli and FMLP in those patients with alcohol dependence. CONCLUSION: The results presented in this study show an impairment in the function of PMN in those patients addicted to alcohol due to the decrease in burst activity. In view of the results of the different stimuli, the second-messenger effects were not evident. A clarification of this phenomenon could well be assumed as an allosteric receptor effect on the burst oxidase, namely, a direct effect on the phagocytosis interaction between circulating granulocytes and causative organisms.

The role of portal vein clamping for cytokine release and neutrophils activity during liver resection and transplant.

OBJECTIVES: Uncontrolled release of cytokines has been linked to graft dysfunction or rejection and contributes to an increase in mortality and morbidity. We argue that temporary vascular clamping of the hepatic pedicle during major hepatic surgery is a potential stimulus for an excessive release of cytokines and the activity of neutrophils. MATERIALS AND METHODS: Thirty patients underwent partial liver resection or transplant. Samples were drawn preoperatively, immediately before portal vein clamping, at the early reperfusion period, and on days 1, 3, 5, and 7 after the operation. Central venous plasma concentrations of IL-6, IL-8, and TNF- a were compared to portal venous plasma. The influence of neutrophils on metabolic activity was measured by flow cytometry. RESULTS: In both patient groups, no significant differences in cytokine concentrations between central and portal venous plasma were found. However, significant differences of neutrophils activity were observed in patients undergoing partial liver resection compared to patients after transplant. CONCLUSION: Portal vein stasis induced by clamping the hepatic pedicle has no influence on the local release of IL-6, IL-8, and TNF-a. However, preoperatively increased plasma levels of TNF-a play a decisive role in the metabolic activity of neutrophils in patients with final-stage liver disease.