A retrospective assessment of the effectiveness of pulsed radiofrequency ablation in the treatment of chronic pain caused by advanced knee osteoarthritis.

INTRODUCTION: Patients suffering from severe chronic pain often have problems finding an appropriate combination of painkillers. We retrospectively evaluated the effectiveness and safety of pulsed radiofrequency ablation (pRFA) of the genicular nerves in 96 patients with knee osteoarthritis (KO). We hypothesized that age, sex, and body mass index (BMI) may influence the quality of the pRFA treatment. MATERIAL AND METHODS: A diagnostic blockade with total volume of 9 ml of 1% lidocaine (WZF, Poland) combined with 4 mg of dexamethasone with subsequent pRFA with a radio frequency of 300-500 kHz under ultrasound guidance was used during the procedure. The study participants were assessed during regular monthly visits until 12 months. RESULTS: The nerves' ultrasound identification was successful in 90.62% of the cases. According to the numeric rating scale (NRS), pain was reduced by 50% or more in 64.06% of the cases. The average pain relief period lasted just over 7 and a half months. There were no pRFA-related complications or side effects of the drugs used. CONCLUSIONS: pRFA seems to be safe and effective for the treatment of chronic pain in KO. The outcome of the treatment may be related to the patient's age (block duration increased with patient age) and sex (in women, the therapeutic effect was more effectively prolonged) in our study group. There was also higher effectiveness of pRFA in high-BMI patients, which was close to statistical significance ( P = 0.053).

Perinatal complications associated with neuraxial blocks.

Regional techniques are the gold standard of obstetric anaesthesia. In both vaginal and Caesarean section deliveries, neuraxial blocks are the most frequently used methods for relieving pain. Although it provides excellent analgesia, regional anaesthesia is associated with certain adverse side effects and possible complications. In this narrative review, we bring together all available data and create a catalogue of complications resulting from the use of perinatal neuraxial anaesthesia which we divide according to their severity and the duration of their impact on patients' health. We focus on complications that have significant or long-term consequences. Even though their incidence is low at 1:1600 neuraxial anaesthetics performed, we believe that better understanding of the possible severe problems that can result from regional anaesthesia procedures would enhance the overall safety of patients during labour, delivery, and the postpartum period. Despite the pivotal role neuraxial techniques play in providing anaesthesia for parturients, there is a lack of good quality studies on the incidence of complications. We believe that a thorough assessment of the occurrence of complications should be carried out by analysing data from nationwide medical databases. By analysing the adverse side effects, both qualitatively and quantitatively, we think it possible to further improve the quality of patient care.

The effect of crystalloid infusion on body water content and intra-abdominal pressure in patients undergoing orthopedic surgery under spinal anesthesia.

BACKGROUND: Crystalloids are frequently used for the correction of spinal anesthesia-induced hypotension, intraoperative bleeding, or vaporisation from surgical wounds. OBJECTIVES: The aim of this study was to observe the effect of perioperative crystalloid infusion on intraabdominal pressure (IAP), volume excess (VE), total body water (TBW), and extracellular body water (ECW) in patients undergoing elective orthopedic surgery under spinal anesthesia. MATERIAL AND METHODS: Adult patients undergoing hip or knee replacement were studied. Changes in VE, TBW, ECW, and IAP were observed in patients who received restrictive fluid therapy (group R) and in patients who received liberal fluid therapy (group L). IAP was measured in the urinary bladder. All parameters were measured at 4 points in time: just before anesthesia (baseline value, A); just after surgery (B); 3 h after surgery (C); and on the morning of postoperative day 1 (D). Additionally, IAP was measured after anesthesia, just before surgery (A1). RESULTS: The mean baseline values of IAP, ECW, TBW, and VE were comparable between groups L and R. The induction of anesthesia reduced IAP in both groups (p < 0.001). IAP and VE increased in both groups after surgery. Significantly higher values of IAP, however, were noted in group L at time points B, C, and D. TBW and ECW increased after surgery in group L. In group R, ECW slightly increased only at time point C. IAP strongly correlated with ECW in group L (p < 0.001, r = 0.62). CONCLUSIONS: Spinal anesthesia reduces IAP. A perioperative increase in body water content and IAP mainly depends on the volume of the infused crystalloids.

Successful 1:1 proportion ventilation with a unique device for independent lung ventilation using a double-lumen tube without complications in the supine and lateral decubitus positions. A pilot study.

INTRODUCTION: Adequate blood oxygenation and ventilation/perfusion matching should be main goal of anaesthetic and intensive care management. At present, one of the methods of improving gas exchange restricted by ventilation/perfusion mismatching is independent ventilation with two ventilators. Recently, however, a unique device has been developed, enabling ventilation of independent lungs in 1:1, 2:1, 3:1, and 5:1 proportions. The main goal of the study was to evaluate the device's utility, precision and impact on pulmonary mechanics. Secondly- to measure the gas distribution in supine and lateral decubitus position. MATERIALS AND METHODS: 69 patients who underwent elective thoracic surgery were eligible for the study. During general anaesthesia, after double lumen tube intubation, the aforementioned control system was placed between the anaesthetic machine and the patient. In the supine and lateral decubitus (left/right) positions, measurements of conventional and independent (1:1 proportion) ventilation were performed separately for each lung, including the following: tidal volume, peak pressure and dynamic compliance. RESULTS: Our results show that conventional ventilation using Robertshaw tube in the supine position directs 47% of the tidal volume to the left lung and 53% to the right lung. Furthermore, in the left lateral position, 44% is directed to the dependent lung and 56% to the non-dependent lung. In the right lateral position, 49% is directed to the dependent lung and 51% to the non-dependent lung. The control system positively affected non-dependent and dependent lung ventilation by delivering equal tidal volumes into both lungs with no adverse effects, regardless of patient's position. CONCLUSIONS: We report that gas distribution is uneven during conventional ventilation using Robertshaw tube in the supine and lateral decubitus positions. However, this recently released control system enables precise and safe independent ventilation in the supine and the left and right lateral decubitus positions.

Plasma magnesium concentration in patients undergoing coronary artery bypass grafting.

[b]Introduction[/b]. Magnesium (Mg) plays a crucial role in cell physiology and its deficiency may cause many disorders which often require intensive treatment. The aim of this study was to analyse some factors affecting preoperative plasma Mg concentration in patients undergoing coronary artery bypass grafting (CABG). [b]Materials and method[/b]. Adult patients scheduled for elective CABG with cardio-pulmonary bypass (CPB) under general anaesthesia were studied. Plasma Mg concentration was analysed before surgery in accordance with age, domicile, profession, tobacco smoking and preoperative Mg supplementation. Blood samples were obtained from the radial artery just before the administration of anaesthesia. [b]Results. [/b]150 patients were studied. Mean preoperative plasma Mg concentration was 0.93 ± 0.17 mmol/L; mean concentration in patients - 1.02 ± 0.16; preoperative Mg supplementation was significantly higher than in patients without such supplementation. Moreover, intellectual workers supplemented Mg more frequently and had higher plasma Mg concentration than physical workers. Plasma Mg concentration decreases in elderly patients. Patients living in cities, on average, had the highest plasma Mg concentration. Smokers had significantly lower plasma Mg concentration than non-smokers. [b]Conclusions. [/b]1. Preoperative magnesium supplementation increases its plasma concentration. 2. Intellectual workers frequently supplement magnesium. 3. Smoking cigarettes decreases plasma magnesium concentration.

An in vivo model of anti-inflammatory activity of subdural dexamethasone following the spinal cord injury.

Current therapies to limit the neural tissue destruction following the spinal cord injury are not effective. Our recent studies indicate that the injury to the white matter of the spinal cord results in a severe inflammatory response where macrophages phagocytize damaged myelin and the fluid-filled cavity of injury extends in size with concurrent and irreversible destruction of the surrounding neural tissue over several months. We previously established that a high dose of 4mg/rat of dexamethasone administered for 1 week via subdural infusion remarkably lowers the numbers of infiltrating macrophages leaving large amounts of un-phagocytized myelin debris and therefore inhibits the severity of inflammation and related tissue destruction. But this dose was potently toxic to the rats. In the present study the lower doses of dexamethasone, 0.125-2.0mg, were administered via the subdural infusion for 2 weeks after an epidural balloon crush of the mid-thoracic spinal cord. The spinal cord cross-sections were analyzed histologically. Levels of dexamethasone used in the current study had no systemic toxic effect and limited phagocytosis of myelin debris by macrophages in the lesion cavity. The subdural infusion with 0.125-2.0mg dexamethasone over 2 week period did not eliminate the inflammatory process indicating the need for a longer period of infusion to do so. However, this treatment has probably lead to inhibition of the tissue destruction by the severe, prolonged inflammatory process.

Prolonged Subdural Infusion of Kynurenic Acid Is Associated with Dose-Dependent Myelin Damage in the Rat Spinal Cord.

BACKGROUND: Kynurenic acid (KYNA) is the end stage metabolite of tryptophan produced mainly by astrocytes in the central nervous system (CNS). It has neuroprotective activities but can be elevated in the neuropsychiatric disorders. Toxic effects of KYNA in the CNS are unknown. The aim of this study was to assess the effect of the subdural KYNA infusion on the spinal cord in adult rats. METHODS: A total of 42 healthy adult rats were randomly assigned into six groups and were infused for 7 days with PBS (control) or 0.0002 pmol/min, 0.01 nmol/min, 0.1 nmol/min, 1 nmol/min, and 10 nmol/min of KYNA per 7 days. The effect of KYNA on spinal cord was determined using histological and electron microscopy examination. Myelin oligodendrocyte glycoprotein (MOG) was measured in the blood serum to assess a degree of myelin damage. RESULT: In all rats continuous long-lasting subdural KYNA infusion was associated with myelin damage and myelin loss that was increasingly widespread in a dose-depended fashion in peripheral, sub-pial areas. Damage to myelin sheaths was uniquely related to the separation of lamellae at the intraperiod line. The damaged myelin sheaths and areas with complete loss of myelin were associated with limited loss of scattered axons while vast majority of axons in affected areas were morphologically intact. The myelin loss-causing effect of KYNA occurred with no necrosis of oligodendrocytes, with locally severe astrogliosis and no cellular inflammatory response. Additionally, subdural KYNA infusion increased blood MOG concentration. Moreover, the rats infused with the highest doses of KYNA (1 and 10 nmol/min) demonstrated adverse neurological signs including weakness and quadriplegia. CONCLUSIONS: We suggest, that subdural infusion of high dose of KYNA can be used as an experimental tool for the study of mechanisms of myelin damage and regeneration. On the other hand, the administration of low, physiologically relevant doses of KYNA may help to discover the role of KYNA in control of physiological myelination process.

Intra-abdominal pressure correlates with extracellular water content.

BACKGROUND: Secondary increase in intra-abdominal pressure (IAP) may result from extra-abdominal pathology, such as massive fluid resuscitation, capillary leak or sepsis. All these conditions increase the extravascular water content. The aim of this study was to analyze the relationship between IAP and body water volume. MATERIAL AND METHODS: Adult patients treated for sepsis or septic shock with acute kidney injury (AKI) and patients undergoing elective pharyngolaryngeal or orthopedic surgery were enrolled. IAP was measured in the urinary bladder. Total body water (TBW), extracellular water content (ECW) and volume excess (VE) were measured by whole body bioimpedance. Among critically ill patients, all parameters were analyzed over three consecutive days, and parameters were evaluated perioperatively in surgical patients. RESULTS: One hundred twenty patients were studied. Taken together, the correlations between IAP and VE, TBW, and ECW were measured at 408 time points. In all participants, IAP strongly correlated with ECW and VE. In critically ill patients, IAP correlated with ECW and VE. In surgical patients, IAP correlated with ECW and TBW. IAP strongly correlated with ECW and VE in the mixed population. IAP also correlated with VE in critically ill patients. ROC curve analysis showed that ECW and VE might be discriminative parameters of risk for increased IAP. CONCLUSION: IAP strongly correlates with ECW.

Effects of unilateral PEEP on biomechanics of both lungs during independent lung ventilation in patients anaesthetised for thoracic surgery.

BACKGROUND: Synchronous independent lung ventilation (ILV) is the treatment of choice for unilateral pathology of lung parenchyma. Numerous studies have documented the improved blood oxygenation and clinical efficacy of this procedure. The aim of the present study was to evaluate the effects of ILV on the selected biomechanical parameters of the lungs. METHOD: The study involved ASA I-II patients undergoing thoracic surgery in the lateral decubitus position under the standard conditions of general anaesthesia with the thoracic cavity closed. ILV with equal separation of the tidal volume was performed with a prototype volume separator, using incremental a PEEP of 0-15 cm H2O in the dependent lung. Peak pressures, dynamic compliance and airway resistance of both lungs were evaluated. RESULTS: The study included 36 patients. In all of the patients, a PEEP of 5-15 cm H2O in one lung increased its peak pressures, dynamic compliance and resistances, and variably affected the biomechanical parameters of the other lung. Irrespective of patient positioning on the right or left side, the highest compliance was recorded at a PEEP of 10 cm H2O. CONCLUSIONS: In ILV, peak pressures and airway resistances are higher in the dependent lung compared to compliances in the non-dependent lung. ILV with a PEEP of 5-15 cm H2O increases the biomechanical parameters of the dependent lung while variably influencing the parameters in the non-dependent lung.

Preoperative neutrophil-lymphocyte count ratio helps predict the grade of glial tumor - a pilot study.

UNLABELLED: Neutrophil-lymphocyte count ratio (NLCR) is a recognized prognostic marker for renal, lung or colorectal carcinomas. The aim of the present study was to determine whether the preoperative value of NLCR might serve as a predictive marker for glial tumors' grading. METHODS: The retrospective analysis of NLCR was performed in neurosurgical patients treated for glial brain tumors. The preoperative NLCR was analyzed in accordance with WHO glial tumors' classification, which distinguishes G1, G2, G3 and G4 (glioblastoma) tumors. RESULTS: The analysis of NLCR was performed in 424 patients (258 males and 166 females) aged 53 ± 16 years who underwent either an open surgery or stereotactic biopsy for a glial brain tumor. G1 was diagnosed in 22 patients, G2 - in 71 patients, G3 - in 63 patients and G4 - in 268 patients. The highest value of NLCR was noted in G4 patients (5.08 [3.1; 8.7] - median [quartiles 1 and 3, respectively]) and was significantly higher compared to G3 (p<0.01), G2 (p<0.001) and G1 (p<0.01) groups. Moreover, NLCR was significantly higher in group G3 than G2 (p<0.05). ROC curve analysis showed 2.579 as a cut-off point for prediction of glioblastoma. CONCLUSION: Preoperative NLCR measurement corresponds with a glial brain tumor grading.

Plasma kynurenic acid concentration in patients undergoing cardiac surgery: effect of anaesthesia.

Increases in plasma kynurenic acid (KYNA) concentration relate to the severity of inflammation. The aim of this study was to analyse changes in plasma KYNA concentration and neutrophil/lymphocyte ratio (NLR) in cardiac surgery patients. Additionally, the effect of anaesthesia was analysed. Adult cardiac surgery patients under intravenous general anaesthesia were studied. Additionally, some patients received sevoflurane (SEV) prior to cardiopulmonary bypass. Plasma KYNA concentration and NLR were measured before anaesthesia, just after surgery and on postoperative days 1, 2 and 3. Patients were assigned to two groups: patients who did not receive SEV (NonSEV group) and patients who received SEV (SEV group). Forty-three patients were studied. Twenty-four of them received SEV. KYNA increased immediately after surgery and remained elevated through postoperative day 3 in the NonSEV group, whereas it was similar to the preoperative concentration in the SEV group. NLR increased immediately after surgery in both groups, and higher values were noted in the NonSEV group than in the SEV group at postoperative days 2 and 3. Plasma KYNA concentration correlated with NLR in the NonSEV group. Cardiac surgery caused an increase in NLR. Plasma KYNA increased in the NonSEV group and correlated with NLR. Administration of SEV inhibited the increase in KYNA, most likely due to its anti-inflammatory properties.

Continuous veno-venous hemofiltration to adjust fluid volume excess in septic shock patients reduces intra-abdominal pressure.

OBJECTIVE: To analyze the effect and the time course of continuous veno-venous hemofiltration (CVVH) with net ultrafiltration (UF) on intra-abdominal pressure (IAP) body fluid volumes in septic shock patients with acute kidney injury (AKI). METHODS: Patients were studied at baseline and after 6, 12, 24, 48, 72, and 96 hours of CVVH treatment. IAP was measured via the bladder, and abdominal perfusion pressure (APP) was calculated as mean arterial pressure minus IAP. Fluid volume excess (VE), total body water (TBW), extracellular body water (ECW), and intracellular body water (ICW) were derived from wholebody bioimpedance analysis (BIA). RESULTS: 30 patients entered final analysis, of which 6 died during CVVH (non-survivors). Fluid VE, TBW, ECW, ICW, and IAP significantly decreased in 24 survivors, whereas these variables remained essentially unchangedin non-survivors. APP slowly increased in survivors, while it did not change in nonsurvivors. IAP strongly correlated with VEin survivors: The lower the IAP, the lower the fluid volume excess. CONCLUSION: CVVH with net UF successfully reduced IAP, TBW, ECW, and ICW in critically ill patients who survived 96 h of CVVH. Failure to increase APP was associated with fatal outcome, and, finally, IAP correlated with fluid volume excess. BIA could be helpful to monitor fluid status in patients with AKI.

Disturbance in venous outflow from the cerebral circulation intensifies the release of blood-brain barrier injury biomarkers in patients undergoing cardiac surgery.

OBJECTIVE: Disturbances in venous outflow from the cerebral circulation may result in brain injury. Severe increases in brain venous pressure lead to brain ischemia and, subsequently, brain edema and intracranial hemorrhages. The purpose of this study was to determine the effect of changes in jugular venous bulb pressure (JVBP) on plasma blood brain-barrier biomarkers concentration and disturbances in arteriovenous total and ionized magnesium (a-vtMg and a-viMg) in brain circulation in patients undergoing coronary artery bypass grafting surgery (CABG) with cardiopulmonary bypass (CPB). DESIGN: Prospective observational study. SETTING: Department of Cardiac Surgery at a Medical University Hospital. PARTICIPANTS: Ninety-two adult patients undergoing elective CABG with CPB under general anaesthesia were studied. METHODS: Central venous pressure (CVP) was measured using a pulmonary artery catheter. The right jugular vein was cannulized retrogradely for jugular venous bulb pressure (JVBP) measurement. Concentrations of plasma S100ß protein, matrix metalloproteinase 9 (MMP-9), creatine kinase isoenzyme BB (CK-BB) a-vtMg and a-viMg were measured as the markers of blood-brain barrier dysfunction. All of them were analyzed in comparison with JVBP during surgery and the early postoperative period. RESULTS: Elevated JVBP was noted after CPB and after surgery. Its increase above 12 mmHg intensified release of S100ß, MMP-9 and CK-BB as well as disorders in a-vtMg and a-viMg. CVP correlated with JVBP, S100ß, and MMP-9. Moreover, JVBP correlated with S100ß and MMP-9. CONCLUSIONS: Cardiac surgery increased JVBP, and JVBP elevated above 12 mmHg intensified an increase in biomarkers of plasma blood-brain barrier disruption.