Factors associated with failed epidural blood patch after accidental dural puncture in obstetrics: a prospective, multicentre, international cohort study.

BACKGROUND: Epidural blood patch is commonly used for management of post-dural puncture headache after accidental dural puncture. The primary aim was to determine factors associated with failed epidural blood patch. METHODS: In this prospective, multicentre, international cohort study, parturients ≥18 yr receiving an epidural blood patch for treatment of post-dural puncture headache were included. Failed epidural blood patch was defined as headache intensity numeric rating scale (NRS) score ≥7 in the upright position at 4, 24, or 48 h, or the need for a second epidural blood patch, and complete success by NRS=0 at 0-48 h after epidural blood patch. All others were considered partial success. Multinominal logistic regression was used for statistical analyses with P<0.01 considered statistically significant. RESULTS: In all, 643 women received an epidural blood patch. Complete data to classify failure were available in 591 (91.9%) women. Failed epidural blood patch occurred in 167 (28.3%) patients; 195 (33.0%) were completely successful and 229 (38.7%) partially successful. A total of 126 women (19.8%) received a second epidural blood patch. A statistically significant association with failure was observed in patients with a history of migraine, when the accidental dural puncture occurred between lumbar levels L1/L3 compared with L3/L5 and when epidural blood patch was performed <48 h compared with ≥48 h after accidental dural puncture. In patients having radiological investigations, three intracranial bleeds were diagnosed. CONCLUSIONS: Failed epidural blood patch occurred in 28.3% of women. Independent modifiable factors associated with failure were higher lumbar level of accidental dural puncture and short interval between accidental dural puncture and epidural blood patch. A history of migraine was associated with a higher risk of second epidural blood patch. CLINICAL TRIAL REGISTRATION: NCT02362828.

Developing a supervised machine learning model for predicting perioperative acute kidney injury in arthroplasty patients.

BACKGROUND: Perioperative acute kidney injury (AKI) is challenging to predict and a common complication of lower limb arthroplasties. Our aim was to create a machine learning model to predict AKI defined by both serum creatinine (sCr) levels and urine output (UOP) and to investigate which features are important for building the model. The features were divided into preoperative, intraoperative, and postoperative feature sets. METHODS: This retrospective, register-based study assessed 648 patients who underwent primary knee or hip replacement at Oulu University Hospital, Finland, between January 2016 and February 2017. The RUSBoost algorithm was chosen to establish the models, and it was compared to Naïve/Kernel Bayes and support vector machine (SVM). Models of AKI classified by either sCr levels or UOP were established. All the models were trained and validated using a five-fold cross-validation approach. An external test set was not available at the time of this study. RESULTS: The performance of both the sCr level- and UOP-based AKI models improved when pre-, intra-, and postoperative features were used together. The best sCr level-based AKI model performed as follows: area under receiving operating characteristic (AUROC) of 0.91, (95% CI ± 0.02), area under precision-recall (AUPR) of 0.35 (95% CI ± 0.04) sensitivity of 0.88 (95% CI ± 0.03), specificity of 0.87 (95% CI ± 0.03), and precision o (95% CI ± 0.03). This model correctly classified 22 out of 25 patients with AKI. The best UOP-based AKI model performed as follows: AUROC of 0.98 (95% CI ± 0.02), AUPR of 0.48 (95% CI ± 0.04), sensitivity of 0.88 (95% CI ± 0.02), specificity of 0.93 (95% CI ± 0.03), and precision of 0.34 (95% CI ± 0.04). This model correctly classified 23 out of 26 patients with AKI. In the sCr-AKI models, estimated glomerular filtration rate (eGFR)-related features were most important, and in the UOP-based AKI models, UOP-related features were most important. Other important and recurring features in the models were age, sex, body mass index, ASA status, operation type, preoperative eGFR, and preoperative sCr level. Naïve/Kernel Bayes performed similarly to RUSBoost. SVM performed poorly. CONCLUSIONS: The performance of the models improved after the inclusion of intra- and postoperative features with preoperative features. The results of our study are not generalizable, and additional larger studies are needed. The optimal ML method for this kind of data is still an open research question.

Procedural Sedation Intubation in a Paramedic-Staffed Helicopter Emergency Medical System in Northern Finland.

OBJECTIVE: Airway management to ensure sufficient gas exchange is of major importance in emergency care. Prehospital endotracheal intubation (ETI) by paramedics is a widely debated method to ensure a patent airway. ETI is performed with procedural sedation in comatose patients because of the regulation. The use of medications increases the rate of successful airway management compared with nonmedication ETI and may also improve outcomes in patients with traumatic brain injury. In the absence of an operative emergency physician and with long distances, paramedic-induced airway management may increase the survival of patients in selected scenarios. A paramedic-staffed helicopter emergency medical system in Northern Finland operates in a rural area without an emergency physician and paralytic medications and treats critically ill patients using basic or advanced life support ground units. The aim of this study was to evaluate the success rates of ETI performed by a small, appropriately trained, and experienced group of 8 nurse paramedics in an out-of-hospital setting. METHODS: The inclusion criterion for the study was an attempted intubation in patients with medical or traumatic indication for airway management by nurse paramedic. RESULTS: Fifty-one patients were treated with ETI. The first-pass success rate was 72.5%, the second-pass success rate was 94.1%, and the overall success rate was 100% within 4 attempts. The median on-scene time was 54 minutes, and there were no signs of aspiration during laryngoscopy or after successful ETI. The primary mortality rate was 11.7%. CONCLUSION: The use of a rigid standard operating procedure for paramedic rapid sequence induction, paralytics, a video laryngoscope, and a gum elastic bougie might positively affect the ETI first-pass success rate. A follow-up study after these future modifications is needed. This small study suggests that intubation might be 1 option for airway management by an experienced nonanesthesiologist in Lapland.

Difference in postoperative opioid consumption after spinal versus general anaesthesia for ankle fracture surgery-A retrospective cohort study.

BACKGROUND: Surgical treatment of ankle fracture is associated with significant pain and high postoperative opioid consumption. The anaesthesia method may affect early postoperative pain. The main objective of the study was to compare postoperative opioid consumption after ankle-fracture surgery between patients treated with spinal anaesthesia and general anaesthesia. METHODS: We reviewed retrospectively the files of 586 adult patients with surgically treated ankle fracture in the years 2014 through 2016. The primary outcome was opioid consumption during the first 48 postoperative hours. Secondary outcomes were maximal pain scores, postoperative nausea and vomiting, the length of stay in the post-anaesthesia care unit, and opioid use in different time periods up to 48 h postoperatively. Propensity score matching was used to mitigate confounding variables. RESULTS: Total opioid consumption 48 h postoperatively was significantly lower after spinal anaesthesia (propensity score-matched population: effect size -13.7 milligrams; 95% CI -18.8 to -8.5; P < .001). The highest pain score on the numerical rating scale in the post-anaesthesia care unit was significantly higher after general anaesthesia (propensity score-matched population: effect size 3.7 points; 95% CI 3.2-4.2; P < .001). A total of 60 patients had postoperative nausea and vomiting in the post-anaesthesia care unit, 53 (88.3%) of whom had general anaesthesia (P = .001). CONCLUSIONS: Patients with surgically treated ankle fracture whose operation was performed under general anaesthesia used significantly more opioids in the first 48 h postoperatively, predominantly in the post-anaesthesia care unit, compared with patients given spinal anaesthesia.

Perioperative acute kidney injury and urine output in lower limb arthroplasties.

BACKGROUND: This study aimed to evaluate the occurrence and perioperative risk factors of acute kidney injury (AKI) in primary elective hip and knee and emergency hip arthroplasty patients. We also aimed to assess the effect of urine output (UOP) as a diagnostic criterion in addition to serum creatinine (sCr) levels. We hypothesized that emergency arthroplasties are prone to AKI and that UOP is an underrated marker of AKI. METHODS: This retrospective, register-based study assessed 731 patients who underwent primary elective knee or hip arthroplasty and 170 patients who underwent emergency hip arthroplasty at Oulu University Hospital, Finland, between January 2016 and February 2017. RESULTS: Of the elective patients, 18 (2.5%) developed AKI. The 1-year mortality rate was 1.5% in elective patients without AKI and 11.1% in those with AKI (P = .038). Of the emergency patients, 24 (14.1%) developed AKI. The mortality rate was 16.4% and 37.5% in emergency patients without and with AKI, respectively (P = .024). In an AKI subgroup analysis of the combined elective and emergency patients, the mortality rate was 31.3% (n = 5) in the sCr group (n = 16), 23.5% (n = 4) in the UOP group (n = 17), and 22.2% (n = 2) in AKI patients who met both the sCr and UOP criteria (n = 9). CONCLUSION: Emergency hip arthroplasty is associated with an increased risk of AKI. Since AKI increases mortality in both elective and emergency arthroplasty, perioperative oliguria should also be considered as a diagnostic criterion for AKI. Focusing solely on sCr may overlook many cases of AKI.

Management practices for postdural puncture headache in obstetrics: a prospective, international, cohort study.

BACKGROUND: Accidental dural puncture is an uncommon complication of epidural analgesia and can cause postdural puncture headache (PDPH). We aimed to describe management practices and outcomes after PDPH treated by epidural blood patch (EBP) or no EBP. METHODS: Following ethics committee approval, patients who developed PDPH after accidental dural puncture were recruited from participating countries and divided into two groups, those receiving EBP or no EBP. Data registered included patient and procedure characteristics, headache symptoms and intensity, management practices, and complications. Follow-up was at 3 months. RESULTS: A total of 1001 patients from 24 countries were included, of which 647 (64.6%) received an EBP and 354 (35.4%) did not receive an EBP (no-EBP). Higher initial headache intensity was associated with greater use of EBP, odds ratio 1.29 (95% confidence interval 1.19-1.41) per pain intensity unit increase. Headache intensity declined sharply at 4 h after EBP and 127 (19.3%) patients received a second EBP. On average, no or mild headache (numeric rating score≤3) was observed 7 days after diagnosis. Intracranial bleeding was diagnosed in three patients (0.46%), and backache, headache, and analgesic use were more common at 3 months in the EBP group. CONCLUSIONS: Management practices vary between countries, but EBP was more often used in patients with greater initial headache intensity. EBP reduced headache intensity quickly, but about 20% of patients needed a second EBP. After 7 days, most patients had no or mild headache. Backache, headache, and analgesic use were more common at 3 months in patients receiving an EBP.

Single dose epidural hydromorphone in labour pain: maternal pharmacokinetics and neonatal exposure.

INTRODUCTION: Epidural hydromorphone could be useful in obstetric analgesia as there is a need for a more water-soluble opioid than sufentanil or fentanyl with prolonged analgesic effect. To our knowledge, the pharmacokinetics of epidural hydromorphone has not been evaluated in parturients. MATERIALS AND METHODS: In this pilot study, seven healthy parturients were given a single epidural dose of hydromorphone for labour pain. One parturient received 1.5 mg, two 0.75 mg and four 0.5 mg of hydromorphone hydrochloride. Dose was decreased due to nausea and pruritus. Hydromorphone's effect, adverse effects and plasma concentrations were evaluated. Neonatal drug exposure was evaluated by umbilical vein and artery opioid concentration at birth. Neonatal outcomes were assessed using Apgar and the Neurologic Adaptive Capacity Score (NACS). RESULTS: All patients received additional levobupivacaine doses on parturients' requests. The first dose was requested at a median of 163 min (range 19-303 min) after hydromorphone administration. A total of 12 opioid related expected adverse events were reported by seven parturients. All newborn outcomes were uneventful. Hydromorphone's distribution and elimination after single epidural dose seem similar to that reported for non-pregnant subjects after intravenous hydromorphone administration, but further research is required to confirm this observation. CONCLUSIONS: The optimal dose of hydromorphone in labour pain warrants further evaluation.

Chronic kidney disease and acute kidney injury in arthroplasty patients over 65 years of age.

BACKGROUND: The purpose of this study was to evaluate the prevalence of chronic kidney disease (CKD) and the incidence of perioperative acute kidney injury (AKI) in primary arthroplasty patients over 65 years of age. Risk factors, perioperative events and the outcome of surgery were evaluated. METHODS: This retrospective, hospital register-based study consists of patients operated in 2014 in the area of Oulu, Finland. The estimated glomerular filtration rate (eGFR) was calculated using the Chronic Kidney Disease Epidemiology Collaboration formula. The incidence of AKI was evaluated based on the serum creatinine criteria of the KDIGO (Kidney Disease, Improving Global Outcomes) classification. RESULTS: Of the 807 patients, 60.8% had mildly decreased (60-89 ml/min/1.73 m2 ) and 13.5% moderately to severely decreased eGFR (<60 ml/min/1.73 m2 ) preoperatively. Only 33.9% of patients with an eGFR < 60 ml/min/1.73 m2 had a diagnosis of a kidney disease. In emergencies, 46.9% of patients with an eGFR < 60 ml/min/1.73 m2 were deceased at the 12-month follow-up point. The measurement of postoperative sCr was not complete (477/807) and was allocated to emergencies and older patient with more comorbidities. Of those whose postoperative sCr was available, 14 (2.9%) fulfilled AKI criteria. Most of the AKI cases had a decrease in eGFR preoperatively, a diagnosed kidney disease or diabetes mellitus. CONCLUSIONS: Impairment of kidney function was common and was related to mortality in emergency arthroplasties. Measurements of postoperative sCr were allocated to high risk patients. Preoperative kidney function, kidney disease and diabetes mellitus were important determinants for perioperative AKI.

Reducing risk of spinal haematoma from spinal and epidural pain procedures.

BACKGROUND AND AIMS: Central neuraxial blocks (CNB: epidural, spinal and their combinations) and other spinal pain procedures can cause serious harm to the spinal cord in patients on antihaemostatic drugs or who have other risk-factors for bleeding in the spinal canal. The purpose of this narrative review is to provide a practise advisory on how to reduce risk of spinal cord injury from spinal haematoma (SH) during CNBs and other spinal pain procedures. Scandinavian guidelines from 2010 are part of the background for this practise advisory. METHODS: We searched recent guidelines, PubMed (MEDLINE), SCOPUS and EMBASE for new and relevant randomised controlled trials (RCT), case-reports and original articles concerning benefits of neuraxial blocks, risks of SH due to anti-haemostatic drugs, patient-related risk factors, especially renal impairment with delayed excretion of antihaemostatic drugs, and specific risk factors related to the neuraxial pain procedures. RESULTS AND RECOMMENDATIONS: Epidural and spinal analgesic techniques, as well as their combination provide superior analgesia and reduce the risk of postoperative and obstetric morbidity and mortality. Spinal pain procedure can be highly effective for cancer patients, less so for chronic non-cancer patients. We did not identify any RCT with SH as outcome. We evaluated risks and recommend precautions for SH when patients are treated with antiplatelet, anticoagulant, or fibrinolytic drugs, when patients' comorbidities may increase risks, and when procedure-specific risk factors are present. Inserting and withdrawing epidural catheters appear to have similar risks for initiating a SH. Invasive neuraxial pain procedures, e.g. spinal cord stimulation, have higher risks of bleeding than traditional neuraxial blocks. We recommend robust monitoring routines and treatment protocol to ensure early diagnosis and effective treatment of SH should this rare but potentially serious complication occur. CONCLUSIONS: When neuraxial analgesia is considered for a patient on anti-haemostatic medication, with patient-related, or procedure-related risk factors, the balance of benefits against risks of bleeding is decisive; when CNB are offered exclusively to patients who will have a reduction of postoperative morbidity and mortality, then a higher risk of bleeding may be accepted. Robust routines should ensure appropriate discontinuation of anti-haemostatic drugs and early detection and treatment of SH. IMPLICATIONS: There is an on-going development of drugs for prevention of thromboembolic events following surgery and childbirth. The present practise advisory provides up-to-date knowledge and experts' experiences so that patients who will greatly benefit from neuraxial pain procedures and have increased risk of bleeding can safely benefit from these procedures. There are always individual factors for the clinician to evaluate and consider. Increasingly it is necessary for the anaesthesia and analgesia provider to collaborate with specialists in haemostasis. Surgeons and obstetricians must be equally well prepared to collaborate for the best outcome for their patients suffering from acute or chronic pain. Optimal pain management is a prerequisite for enhanced recovery after surgery, but there is a multitude of additional concerns, such as early mobilisation, early oral feeding and ileus prevention that surgeons and anaesthesia providers need to optimise for the best outcome and least risk of complications.

Epileptiform and periodic EEG activities induced by rapid sevoflurane anaesthesia induction.

OBJECTIVES: The aim of the study was to compare the EEG findings and haemodynamic parameters of adult male patients while undergoing mask induction with sevoflurane anaesthesia with either controlled hyperventilation (CH) or spontaneous breathing (SB). METHODS: Twenty male patients, aged 23-52 (mean 42) years were anaesthetized randomly with either spontaneous breathing or mild controlled hyperventilation via mask. EEG was recorded using a full 10-20 electrode set. RESULTS: Anaesthesia induction with high inhaled concentrations of sevoflurane produced several epileptiform and periodic EEG patterns. CH doubled the amount of these EEG patterns compared to SB. Higher heart rate was recorded in the CH group. CONCLUSIONS: We describe a high incidence of paroxysmal EEG activity: epileptiform and generalized periodic discharges (GPDs) during rapid sevoflurane in nitrous oxide-oxygen mask induction in hyperventilated male patients. However these activities have no effect to the heart rate or the mean arterial pressure. SIGNIFICANCE: The monitoring of GPDs and burst suppression patterns during rapid anaesthesia induction with sevoflurane provides possibility to study the effects of volatile anaesthetics in the healthy brain. In order to analyse the different sources of EEG patterns a wide-band multichannel EEG recording is necessary.

Incidence and predictive factors of spinal cord stimulation treatment after lumbar spine surgery.

INTRODUCTION: Spinal cord stimulation (SCS) is recommended for the treatment of postsurgical chronic back and leg pain refractory to other treatments. We wanted to estimate the incidence and predictive factors of SCS treatment in our lumbar surgery cohort. PATIENTS AND METHODS: Three questionnaires (a self-made questionnaire, the Oswestry Low Back Pain Disability Questionnaire, and the Beck Depression Inventory) were sent to patients aged 18-65 years with no contraindications for the use of SCS, and who had undergone non-traumatic lumbar spine surgery in the Oulu University Hospital between June 2005 and May 2008. Patients who had a daily pain intensity of ≥5/10 with predominant radicular component were interviewed by telephone. RESULTS: After exclusions, 814 patients remained in this cohort. Of those, 21 patients had received SCS by the end of June 2015. Fifteen (71%) of these received benefit and continued with the treatment. Complications were rare. The number of patients who replied to the postal survey were 537 (66%). Eleven of them had undergone SCS treatment after their reply. Features predicting SCS implantation were daily or continuous pain, higher intensities of pain with predominant radicular pain, more severe pain-related functional disability, a higher prevalence of depressive symptoms, and reduced benefit from pain medication. The mean waiting time was 65 months (26-93 months). One hundred patients were interviewed by telephone. Fourteen seemed to be potential SCS candidates. From the eleven patients who underwent SCS after responding to the survey, two were classified as potential candidates in the phone interview, while nine were other patients. Twelve patients are still waiting for treatment to commence. CONCLUSION: In our region, the SCS treatment is used only for very serious pain conditions. Waiting time is too long and it may be the reason why this treatment option is not offered to all candidates.

Real-time monitoring of human blood-brain barrier disruption.

Chemotherapy aided by opening of the blood-brain barrier with intra-arterial infusion of hyperosmolar mannitol improves the outcome in primary central nervous system lymphoma. Proper opening of the blood-brain barrier is crucial for the treatment, yet there are no means available for its real-time monitoring. The intact blood-brain barrier maintains a mV-level electrical potential difference between blood and brain tissue, giving rise to a measurable electrical signal at the scalp. Therefore, we used direct-current electroencephalography (DC-EEG) to characterize the spatiotemporal behavior of scalp-recorded slow electrical signals during blood-brain barrier opening. Nine anesthetized patients receiving chemotherapy were monitored continuously during 47 blood-brain barrier openings induced by carotid or vertebral artery mannitol infusion. Left or right carotid artery mannitol infusion generated a strongly lateralized DC-EEG response that began with a 2 min negative shift of up to 2000 µV followed by a positive shift lasting up to 20 min above the infused carotid artery territory, whereas contralateral responses were of opposite polarity. Vertebral artery mannitol infusion gave rise to a minimally lateralized and more uniformly distributed slow negative response with a posterior-frontal gradient. Simultaneously performed near-infrared spectroscopy detected a multiphasic response beginning with mannitol-bolus induced dilution of blood and ending in a prolonged increase in the oxy/deoxyhemoglobin ratio. The pronounced DC-EEG shifts are readily accounted for by opening and sealing of the blood-brain barrier. These data show that DC-EEG is a promising real-time monitoring tool for blood-brain barrier disruption augmented drug delivery.

Pilot Study of Propofol-induced Slow Waves as a Pharmacologic Test for Brain Dysfunction after Brain Injury.

BACKGROUND: Slow waves (less than 1 Hz) are the most important electroencephalogram signatures of nonrapid eye movement sleep. While considered to have a substantial importance in, for example, providing conditions for single-cell rest and preventing long-term neural damage, a disturbance in this neurophysiologic phenomenon is a potential indicator of brain dysfunction. METHODS: Since, in healthy individuals, slow waves can be induced with anesthetics, the authors tested the possible association between hypoxic brain injury and slow-wave activity in comatose postcardiac arrest patients (n = 10) using controlled propofol exposure. The slow-wave activity was determined by calculating the low-frequency (less than 1 Hz) power of the electroencephalograms recorded approximately 48 h after cardiac arrest. To define the association between the slow waves and the potential brain injury, the patients' neurologic recovery was then followed up for 6 months. RESULTS: In the patients with good neurologic outcome (n = 6), the low-frequency power of electroencephalogram representing the slow-wave activity was found to substantially increase (mean ± SD, 190 ± 83%) due to the administration of propofol. By contrast, the patients with poor neurologic outcome (n = 4) were unable to generate propofol-induced slow waves. CONCLUSIONS: In this experimental pilot study, the comatose postcardiac arrest patients with poor neurologic outcome were unable to generate normal propofol-induced electroencephalographic slow-wave activity 48 h after cardiac arrest. The finding might offer potential for developing a pharmacologic test for prognostication of brain injury by measuring the electroencephalographic response to propofol.

Promising treatment results with blood brain barrier disruption (BBBD) based immunochemotherapy combined with autologous stem cell transplantation (ASCT) in patients with primary central nervous system lymphoma (PCNSL).

Primary central nervous system lymphoma (PCNSL) is a rare brain tumour with a dismal prognosis. Several phase II studies with high-dose methotrexate-based regimens have shown promising early results, but in all hospital-based data published so far, the disease outcome has been poor. Patients with relapsed or refractory disease have a dismal prognosis. We performed retrospective analysis to evaluate results and tolerabilities of BBBD therapy in combination with high-dose therapy supported by autologous stem cell transplantation. We analysed 25 patients (age range: 40-71 years) who were treated in first or second line with BBBD therapy. When we started BBBD treatment, patients had relapsed or refractory PCNSL or they did not tolerate Bonn-like therapy. In recent years, some of the patients were treated in first line. We found promising response rates. Altogether 19 (76 %) of the patients achieved a complete response (CR). Two-year progression-free survival (PFS) and overall survival (OS) rates were 61 and 57 % respectively and the five-year OS was 47 %. Patients who were treated with a five-drug therapy had a very promising prognosis. The CR rate was 100 % in first-line therapy and 60 % in relapsed cases. These findings suggest that BBBD is a promising therapy for PCNSL, especially for patients in first line, but also for patients with relapsed or refractory disease after conventional chemotherapy, who commonly have a very poor prognosis. Treatment-related toxicity was generally manageable. Thus, BBBD followed by ASCT could be a treatment of choice in transplant-eligible patients with PCNSL.

Obesity has an impact on outcome in lumbar disc surgery.

PURPOSE: To investigate the effect of obesity on outcome in lumbar discectomy. METHODS: A cross-sectional postal survey; a self-made questionnaire, Beck depression inventory IA (BDI IA) and the Oswestry low back disability questionnaire (ODI) were sent to the patients, who had undergone lumbar disc surgery in the Oulu University Hospital between June 2005 and May 2008. Patients were divided into three groups according to BMI: normal, pre-obese and obese. The ODI was also examined in the framework of the international classification of functioning, disability and health (ICF) to investigate its ability to describe various dimensions of functioning (body structure and functions, activities and participation). RESULTS: The postal survey was sent to 642 patients, of whom 355 (55%) replied. Males dominated in the pre-obese (66%) and obese (62%) groups (p=0.01). Normal-weighted and pre-obese patients had lower BDI scores compared to obese patients (mean BDI: 8.0, 7.6, 11.2, respectively, p=0.035). Total ODI score was highest in the obese group compared to normal-weighted or pre-obese (20.3, 18.6, 26.4, respectively, p=0.011). When ODI was linked to the ICF there were significant differences in all activity domains (mobility, self-care and interpersonal interactions and relationships) and the mobility component of the participation domain between the weight groups. CONCLUSIONS AND IMPLICATIONS: Obesity has an impact on outcome in lumbar discectomy. Obese patients had higher scores in BDI and ODI indicating mild mood disturbances and moderate functional disability. According to ICF, functional disability of obese patients was observed to some extent in all activity domains. Obese patients will be more frequently present for disc surgery and increased morbidity risk must be recognized. We need a strategy to rehabilitate and activate obese patients pre- and postoperatively.

Using Hilbert-Huang Transform to assess EEG slow wave activity during anesthesia in post-cardiac arrest patients.

Hypoxic ischemic encephalopathy (HIE) is a severe consequence of cardiac arrest (CA) representing a substantial diagnostic challenge. We have recently designed a novel method for the assessment of HIE after CA. The method is based on estimating the severity of the brain injury by analyzing changes in the electroencephalogram (EEG) slow wave activity while the patient is exposed to an anesthetic drug propofol in a controlled manner. In this paper, Hilbert-Huang Transform (HHT) was used to analyze EEG slow wave activity during anesthesia in ten post-CA patients. The recordings were made in the intensive care unit 36-48 hours after the CA in an experiment, during which the propofol infusion rate was incrementally decreased to determine the drug-induced changes in the EEG at different anesthetic levels. HHT was shown to successfully capture the changes in the slow wave activity to the behavior of intrinsic mode functions (IMFs). While, in patients with good neurological outcome defined after a six-month control period, propofol induced a significant increase in the amplitude of IMFs representing the slow wave activity, the patients with poor neurological outcome were unable to produce such a response. Consequently, the proposed method offer substantial prognostic potential by providing a novel approach for early estimation of HIE after CA.

Peripheral morphine reduces acute pain in inflamed tissue after third molar extraction: A double-blind, randomized, active-controlled clinical trial.

BACKGROUND: The clinical use of peripheral analgesic effects of opioids has been investigated in numerous controlled clinical trials. The majorities of these have tested the local, intra-articular administration of morphine in knee surgery and have demonstrated marginal postoperative analgesia. OBJECTIVE: We examined direct morphine infiltration of the surgical site in a clinical model of tooth pain under two different conditions. Eighty-eight patients undergoing surgical tooth removal entered into the two prospective, parallel, randomized, double-blind studies. METHODS: Patients undergoing surgical tooth removal received a standard local anaesthetic solution (articaine plus epinephrine) before surgery. Patients were assigned to an injection of peripheral 2mg morphine either into non-inflamed (Trial I) or inflamed (Trial II) submucous tissue before the surgery. Patients who received an intramuscular morphine in the upper arm were concomitantly given 1ml isotonic saline (NaCl) as a submucous injection. Patients who received a submucous injection of morphine peripherally were concomitantly given an intramuscular injection (IM) of 1ml of NaCl in the upper arm. Postoperative pain intensity was assessed by the numeric rating scale every 30min for the first 2h and then every hour for the next 8h after surgery. In addition, patients recorded the occurrence of side effects and the supplemental consumption of ibuprophen and codeine+paracetamol combination tablets. RESULTS: Of the eighty-eight original participants, nine patients (4 patients in Trial I and 5 patients in Trial II) were withdrawn for protocol noncompliance and loss at follow-up. Thirty-one patients in trial I and forty-eight patients in trial II were analyzed. Patients receiving 2mg morphine into non-inflamed tissue did not show any further reduction in pain scores and pain medication consumption compared to IM morphine group (Trial I). In patients receiving 2mg morphine into inflamed tissue, pain scores at rest were reduced to a similar extent in both groups at all measurement times up to 10h in the follow-up (Trial II). At the same time, in the area under the curves pain scores on swallowing between 2 and 6h in the peripheral morphine group (5.2±5.6) were significantly lower than in the IM morphine group (9.3±7.3, p=0.03), demonstrating the marginal analgesic efficacy of additional morphine. Sedation scores were significantly higher in the peripheral morphine group only 1h after surgery in Trial I (p=0.008). The time to first analgesic intake was similar between groups. No serious side effects were reported. CONCLUSIONS: Our results showed in patients undergoing surgical tooth removal that injection of 2mg of morphine into inflamed tissue results in significantly lower pain scores on swallowing in the early postoperative state while administration into non-inflamed tissue is not effective. IMPLICATIONS: Our studies indicate that the peripheral administration of opioids, at the doses and conditions set out for these two studies, produces significant analgesia by a pharmacologically specific mechanism that is active in chronically, but not acutely, inflamed tissue. Thus, consistent with preclinical experimental studies, the requirement of an inflammatory process for the occurrence of the peripheral opioid effects is also found in the clinical setting.