Showing papers in "Acta Anaesthesiologica Scandinavica in 2007"

Good clinical research practice in pharmacodynamic studies of neuromuscular blocking agents II: the Stockholm revision.

Abstract: The set of guidelines for good clinical research practice (GCRP) in pharmacodynamic studies of neuromuscular blocking agents, which was developed following an international consensus conference in Copenhagen, has been revised and updated following the second consensus conference in Stockholm in 2005. It is hoped that these guidelines will continue to help researchers in the field and assist the pharmaceutical industry and equipment manufacturers in enhancing the standards of the studies they sponsor.

Neurogenic pulmonary edema.

Abstract: Neurogenic pulmonary edema (NPE) is usually defined as an acute pulmonary edema occurring shortly after a central neurologic insult. It has been reported regularly for a long time in numerous and various injuries of the central nervous system in both adults and children, but remains poorly understood because of the complexity of its pathophysiologic mechanisms involving hemodynamic and inflammatory aspects. NPE seems to be under-diagnosed in acute neurologic injuries, partly because the prevention and detection of non-neurologic complications of acute cerebral insults are not at the forefront of the strategy of physicians. The presence of NPE should be high on the list of diagnoses when patients with central neurologic injury suddenly become dyspneic or present with a decreased P(a)o(2)/F(i)o(2) ratio. The associated mortality rate is high, but recovery is usually rapid with early and appropriate management. The treatment of NPE should aim to meet the oxygenation needs without impairing cerebral hemodynamics, to avoid pulmonary worsening and to treat possible associated myocardial dysfunction. During brain death, NPE may worsen myocardial dysfunction, preventing heart harvesting.

Monitoring of peri‐operative fluid administration by individualized goal‐directed therapy

Abstract: Background: In order to avoid peri-operative hypovolaemia or fluid overload, goal-directed therapy with individual maximization of flow-related haemodynamic parameters has been introduced. The objectives of this review are to update research in the area, evaluate the effects on outcome and assess the use of strategies, parameters and monitors for goal-directed therapy. Methods: A MEDLINE search (1966 to 2 October 2006) was performed to identify studies in which a goal-directed therapeutic strategy was used to maximize flow-related haemodynamic parameters in surgical patients, as well as studies referenced from these papers. Furthermore, methods applied in these studies and other monitors with a potential for goal-directed therapy are described. Results: Nine studies were identified pertaining to fluid optimization during the intra- and post-operative period with goaldirected therapy. Seven studies (n ¼ 725) found a reduced hospital stay. Post-operative nausea and vomiting (PONV) and ileus were reduced in three studies and complications were reduced in four studies. Of the monitors that may be applied for goal-directed therapy, only oesophageal Doppler has been tested adequately; however, several other options exist. Conclusion: Goal-directed therapy with the maximization of flow-related haemodynamic variables reduces hospital stay, PONV and complications, and facilitates faster gastrointestinal functional recovery. So far, oesophageal Doppler is recommended, but other monitors are available and call for evaluation.

Scandinavian Clinical Practice Guidelines on the diagnosis, management and follow-up of anaphylaxis during anaesthesia

Abstract: The present approach to the diagnosis, management and follow-up of anaphylaxis during anaesthesia varies in the Scandinavian countries. The main purpose of these Scandinavian Clinical Practice Guidelines is to increase the awareness about anaphylaxis during anaesthesia amongst anaesthesiologists. It is hoped that increased focus on the subject will lead to prompt diagnosis, rapid and correct treatment, and standardised management of patients with anaphylactic reactions during anaesthesia across Scandinavia. The recommendations are based on the best available evidence in the literature, which, owing to the rare and unforeseeable nature of anaphylaxis, mainly includes case series and expert opinion (grade of evidence IV and V). These guidelines include an overview of the epidemiology of anaphylactic reactions during anaesthesia. A treatment algorithm is suggested, with emphasis on the incremental titration of adrenaline (epinephrine) and fluid therapy as first-line treatment. Recommendations for primary and secondary follow-up are given, bearing in mind that there are variations in geography and resources in the different countries. A list of National Centres from which anaesthesiologists can seek advice concerning follow-up procedures is provided. In addition, an algorithm is included with advice on how to manage patients with previous suspected anaphylaxis during anaesthesia. Lastly, Appendix 2 provides an overview of the incidence, mechanisms and possibilities for follow-up for some common drug groups.

Therapeutic hypothermia after out-of-hospital cardiac arrest: experiences with patients treated with percutaneous coronary intervention and cardiogenic shock.

Abstract: Background: Therapeutic hypothermia has been shown to increase survival after out-of-hospital cardiac arrest (OHCA). The trials documenting such benefit excluded patients with cardiogenic shock and only a few patients were treated with percutaneous coronary intervention prior to admission to an intensive care unit (ICU). We use therapeutic hypothermia whenever cardiac arrest patients do not wake up immediately after return of spontaneous circulation. Methods: This paper reports the outcome of 50 OHCA patients with ventricular fibrillation admitted to a tertiary referral hospital for immediate coronary angiography and percutaneous coronary intervention when indicated. Patients were treated with intraaortic balloon counterpulsation (IABP) (23 of 50 patients) if indicated. All patients who were still comatose were treated with therapeutic hypothermia at 32–34 8C for 24 h before rewarming. The end-points were survival and cerebral performance category (CPC: 1, best; 5, dead) after 6 months. Results: Forty-one patients (82%) survived until 6 months. Thirty-four patients (68%) were in CPC 1 or 2, and seven (14%) were in CPC 3. Of the 23 patients treated with IABP, 14 (61%) survived with CPC 1 or 2. In patients not treated with IABP, 20 patients (74%) survived with CPC 1 or 2. Forty patients (80%) developed myocardial infarction. Percutaneous coronary intervention was performed in 36 patients (72%). Conclusion: In OHCA survivors who reached our hospital, the survival rate was high and the neurological outcome acceptable. Our results indicate that the use of therapeutic hypothermia is justified even in haemodynamically unstable patients and those treated with percutaneous coronary intervention.

Prevalence of self-reported neuropathic pain and impact on quality of life: a prospective representative survey.

Abstract: Background: Data on the incidence of neuropathic pain (NeP) in Austria, its general characteristics and consequences for the quality of life (QOL) are still lacking. The prevalence in the United Kingdom is 8%. Methods: A representative survey (n=7707) was carried out. Patients with NeP were identified using previously validated criteria and subsequently asked to complete a questionnaire on QOL and detailed pain characteristics. Results: The prevalence of NeP was 3.3% (n=260). A higher prevalence was found in 41–50-year-olds (26%) and 51–60 year olds (24%). Pain was long lasting (>1 year: 66%; >5 years: 41%) and severe at onset (mean 6.8; numerical rating scale) as well as later (mean 4.7; 20% 8 or higher). Strong or predominant restriction of daily activities was reported in 65%, strong or predominant sleep disturbances in 60%, feelings of depression in 34% and anxiety in 25%. Conclusion: For the first time, data on the prevalence of NeP in Austria are available. Pain patterns in those affected are characteristic and impact on QOL as well as pain intensity are severe.

Stressful memories and psychological distress in adult mechanically ventilated intensive care patients - a 2-month follow-up study

Abstract: Aim: To investigate patients' psychological distress in relation to memory and stressful experiences in the intensive care unit (ICU), and to identify early predictors for the development of high levels of acute post-traumatic stress disorder (PTSD)-related symptoms. Methods: A prospective cohort study was performed over 18 months in two general ICUs, including 313 intubated mechanically ventilated adults admitted for more than 24 h, 226 of whom completed the study. Patients were interviewed 5 days and 2 months post-ICU concerning their memories and psychological distress. The instruments used were the ICU Memory Tool, ICU Stressful Experience Questionnaire, Hospital Anxiety and Depression Scale and Impact of Event Scale-Revised (IES-R). Results: High symptom levels of anxiety, depression and acute PTSD 2 months post-ICU were present in 4.9%, 7.5% and 8.4% of the 226 patients, respectively. Psychological distress 2 months post-ICU was associated with experiences of the ICU rated as extremely stressful and with high levels of anxiety and depression 5 days post-ICU, but not with amnesia or delusional memories without factual recall of the ICU. Female sex, signs of agitation (increasing proportion of Motor Activity Assessment Scale scores of 4-6) and feelings of extreme fear during the ICU stay were significantly and independently associated with IES-R scores of 30 or more. Conclusions: Extremely stressful experiences of the ICU are associated with subsequent psychological distress. Female sex, agitation and extreme fear during the ICU stay seem to increase the risk of developing high levels of acute PTSD-related symptoms.

Obstetric anesthesia for the obese and morbidly obese patient: an ounce of prevention is worth more than a pound of treatment

Abstract: Background: The incidence of obesity has been dramatically increasing across the globe. Anesthesiologists, are increasingly faced with the care for these patients. Obesity in the pregnant woman is associated with a broad spectrum of problems, including dramatically increased risk for cesarean delivery, diabetes, hypertension and pre-eclampsia. A thorough understanding of the physiology, associated conditions and morbidity, available options for anesthesia and possible complications is therefore important for today's anesthesiologist. Methods: This is a personal review in which different aspects of obesity in the pregnant woman, that are relevant to the anesthesiologist, are discussed. An overview of maternal and fetal morbidity and physiologic changes associated with pregnancy and obesity is provided and different options for labor analgesia, the anesthetic management for cesarean delivery and potential post-partum complications are discussed in detail. Results and conclusion: The anesthetic management of the morbidly obese parturient is associated with special hazards. The risk for difficult or failed intubation is exceedingly high. The early placement of an epidural or intrathecal catheter may overcome the need for general anesthesia, however, the high initial failure rate necessitates critical block assessment and catheter replacement when indicated.

Neurologic and histologic outcome after intraneural injections of lidocaine in canine sciatic nerves.

Abstract: Background: Inadvertent intraneural injection of local anesthetics may result in neurologic injury. We hypothesized that an intraneural injection may be associated with higher injection pressures and an increase in the risk of neurologic injury. Methods: The study was conducted in accordance with the principles of laboratory animal care, and was approved by the Laboratory Animal Care and Use Committee. Fifteen dogs of mixed breed (16–21 kg) were studied. After general endotracheal anesthesia, the sciatic nerves (n= 30) were exposed bilaterally. Under direct vision, a 25-gauge, long-beveled needle (30°) was placed either epineurally (n= 10) or intraneurally (n= 20), and 4 ml of preservative-free lidocaine 20 mg/ml was injected using an automated infusion pump (4 ml/min). Injection pressure data were acquired using an in-line manometer coupled to a computer via an analog-to-digital conversion board. After injection, the animals were awakened and subjected to serial neurologic examinations. One week later, the dogs were killed, the sciatic nerves excised and histologic examination was performed by pathologists blind to the purpose of the study. Results: All perineural injections resulted in low pressures (≤ 5 psi). In contrast, eight of 20 intraneural injections resulted in high pressures (20–38 psi) at the beginning of the injection. Twelve intraneural injections, however, resulted in pressures of less than 12 psi. Neurologic function returned to baseline within 3 h after perineural injections and within 24 h after intraneural injections, when the measured injection pressures were less than 12 psi. Neurologic deficits persisted throughout the study period after all eight intraneural injections that resulted in high injection pressures. Histologic examination of the affected nerves revealed fascicular axonolysis and cellular infiltration. Conclusions: The data in our canine model of intraneural injection suggest that intraneural injections do not always lead to nerve injury. High injection pressures during intraneural injection may be indicative of intrafascicular injection and may predict the development of neurologic injury.

Combined intrathecal and epidural magnesium sulfate supplementation of spinal anesthesia to reduce post-operative analgesic requirements: a prospective, randomized, double-blind, controlled trial in patients undergoing major orthopedic surgery.

Abstract: Background: New ways of decreasing post-operative analgesic drug requirements are of special interest after major surgery. Magnesium sulfate (MgSO4) alters pain processing and reduces the induction and maintenance of central sensitization by blocking the N-methyl-d-aspartate (NMDA) receptor in the spinal cord. We investigated whether supplementation of spinal anesthesia with combined intrathecally and epidurally infused MgSO4 reduced patients’ post-operative analgesia requirements. Methods: In a randomized, prospective, double-blind, placebo-controlled trial, we enrolled 120 consecutive patients undergoing orthopedic surgery during spinal anesthesia (levobupivacaine and sufentanil). Patients were randomly assigned to receive intrathecal MgSO4 (94.5 mg, 6.3%), epidural MgSO4 (2%, 100 mg/h), intrathecal and epidural MgSO4 combined or spinal anesthesia alone (controls). Post-operative morphine consumption was assessed in all groups by patient-controlled analgesia (PCA). Results: Of the 120 patients enrolled, 103 (86%) completed the study. Morphine consumption at 36 h after surgery was 38% lower in patients receiving spinal anesthesia plus epidural MgSO4 [– 14.963 mg; 95% confidence interval (CI), – 1.44 to – 28.49 mg], 49% lower in those receiving spinal anesthesia plus intrathecal MgSO4 (– 18.963 mg; 95% CI, – 5.27 to – 32.65 mg) and 69% lower in the intrathecal–epidural combined group (– 26.963 mg; 95% CI, – 13.73 to – 40.19 mg) relative to control patients receiving spinal anesthesia alone. No complications developed during the post-operative course or at 1 month after surgery. Conclusion: In patients undergoing orthopedic surgery, supplementation of spinal anesthesia with combined intrathecal and epidural MgSO4 significantly reduces patients’ post-operative analgesic requirements.

Current practice of hemodynamic monitoring and vasopressor and inotropic therapy in post-operative cardiac surgery patients in Germany: results from a postal survey.

Abstract: Background: In Germany, more than 100,000 patients are monitored and treated in 80 intensive care units (ICUs) following cardiac surgery each year. The controversies concerning the different methods of hemodynamic monitoring and the appropriate agents for volume therapy and inotropic support are well known. However, little is known about how monitoring and treatment are currently performed. Methods: A questionnaire with 39 questions was sent to the leading physicians of 80 ICUs in Germany, treating patients after cardiac surgery. The questions to be answered covered the current practice of hemodynamic monitoring, volume replacement, inotropic/vasopressor support and transfusions in patients after cardiac surgery. Results: Sixty-nine per cent of the questionnaires were completed and returned. All ICUs used basic monitoring as recommended by the societies. The use of advanced hemodynamic monitoring included the pulmonary artery catheter (58.2%), transesophageal echocardiography (38.1%) and transpulmonary dilution techniques (13%). Crystalloids (21.2%) and colloids (73%) were used for volume replacement. Epinephrine (41.8%) and dobutamine (30.9%) were the first-choice inotropic drugs for the treatment of low cardiac output syndrome, followed by phosphodiesterase inhibitors (14.5%). Second-choice drugs for the treatment of low cardiac output syndrome were enoximone (29%), milrinone (25%) and dobutamine (25%). A written transfusion protocol and a transfusion threshold for red blood cells existed in 59% and 79% of ICUs, respectively. Conclusion: Hemodynamic monitoring and the variability in clinical practice with regard to volume replacement, transfusion triggers and the use of vasopressors/inotropes in cardiac surgery patients tend to follow the results of traditional experience rather than current scientific knowledge. Guidelines are therefore necessary to help to improve the standards of intensive care after cardiac surgery and thus the outcome of patients.

Severe head injury : control of physiological variables, organ failure and complications in the intensive care unit

Abstract: Background: In patients with severe head injury, control of physiological variables is important to avoid intracranial hypertension and secondary injury to the brain. The aims of this retrospective study were to evaluate deviations of physiological variables and the incidence of extracranial complications in patients with severe head injury. We also studied if these deviations could be related to outcome. Patients and methods: One hundred and thirty-three patients were included during a 5-year period (1998–2002). Deviations from treatment goals for the following physiological variables were studied: blood pressure, haemoglobin, blood sugar, serum sodium, serum albumin and temperature. Extra cerebral organ complications were also recorded as well as outcome at 6 months. Results: The median age was 32 years (range; 1–88 years). Median Glasgow Coma Scale (GCS) before intubation was 6 (range; 3–14). The frequencies of severe deviations from the desired values of the physiological variables for at least one treatment day were: hypotensive episodes (systolic BP 10 mmol/l – 26%, serum sodium concentration 39 °C – 24%. Pneumonia was diagnosed in 71% and Acute Lung Injury (ALI)/Adult Respiratory Distress Syndrome (ARDS) in 26% of the patients. Other complications such as severe sepsis (6%), renal failure (1.5%), a coagulation disorder (6%) and liver failure (one patient) were infrequent. Age, GCS, hypotension during the first day of treatment, elevated blood sugar and low albumin predicted an unfavourable outcome. Conclusions: Deviations of key physiological variables and pulmonary complications were frequent in patients suffering from severe head injury. During intensive care treatment, hypotension, elevated blood sugar and hypoalbuminemia are possible independent predictors of an unfavourable outcome.

Control of shivering during regional anaesthesia: prophylactic ketamine and granisetron

Abstract: Background: The aim of the present study was to compare placebo, ketamine, granisetron and a combination of ketamine and granisetron in the prevention of shivering caused by regional anaesthesia. Methods: In this prospective, randomized, double-blind study, 160 ASA I and II patients undergoing urological surgery were included. Subarachnoid anaesthesia was performed in all patients with bupivacaine 15 mg. The patients were randomly allocated to receive saline (group P, n= 40), ketamine 0.5 mg (group K, n= 40), granisetron 3 mg (group G, n= 40) or ketamine 0.25 mg + granisetron 1.5 mg (group KG, n= 40). Shivering was graded as 0 = no shivering, 1 = piloerection or peripheral vasoconstriction but no visible shivering, 2 = muscular activity in only one muscle group, 3 = muscular activity in more than one muscle group but not generalized, and 4 = shivering involving the whole body. If 15 min after spinal anaesthesia and concomitant administration of a prophylactic dose of one of the study drugs, the patients shivered according to at least grade 3, the prophylaxis was regarded as ineffective and intravenous (i.v.) pethidine 25 mg was administered. Results: After 15 min, the number of patients with observed shivering was 22 in group P, 6 in group G, 7 in group GK and 0 in group K. The difference between group K and all the other groups was statistically significant (P < 0.0001). The number of patients with a shivering score of 3 was statistically significantly higher in group P compared with the other groups. Conclusion: The prophylactic use of 0.5 mg/kg i.v. ketamine was effective in preventing shivering developed during regional anaesthesia.

Inflammation and infection complications of 2285 perineural catheters: a prospective study.

Abstract: Background: Perineural catheters (PNCs) are increasingly being used. Few data are available on the infectious complications of PNCs. The incidence and localization of local inflammation and infection associated with PNCs were assessed. Methods: PNCs placed under sterile conditions for regional anesthesia and post-operative analgesia were evaluated prospectively. Local inflammation was defined as redness, swelling or pain on pressure at the catheter insertion site. Infection was defined as purulent material at the catheter insertion site with or without the need for surgical intervention. Results: In total, 2285 PNCs were evaluated: 600 axillary, 303 interscalene, 92 infraclavicular, 65 psoas compartment, 574 femoral, 296 sciatic and 355 popliteal. Local inflammation occurred in 4.2% and infection in 3.2%. The duration of PNC placement was a risk factor (P < 0.05). Surgical intervention was necessary in 0.9%. No late complications occurred in any patient. Interscalene catheters were associated with an increased risk of infection (4.3%; P < 0.05). Anterior proximal sciatic catheters were associated with a lower risk of local inflammation (1.7%; P < 0.05) and infection (0.4%; P < 0.05). Staphylococcus epidermidis and Staphylococcus aureus were isolated in 42% and 58% of catheter tip cultures, respectively. Conclusion: In the present study population, infection of PNCs was a rare occurrence, but the incidence increased with the duration of PNC placement, and close clinical monitoring is required.

Chronic non‐malignant pain patients report as poor health‐related quality of life as palliative cancer patients

Abstract: IntroductionThe patients with the most severe and complex chronic non-malignant pain (CNMP) conditions are admitted to multidisciplinary pain centres. A poor health related quality of life (HRQoL) has been documented in these patients but their HRQoL scores have to a very limited degree been compared to other patient groups. Such comparisons require the application of the same HRQoL instruments in different populations. While nonpharmacological treatment is preferred in this patient group, treatment with strong opioids is an option for some patients. After start of opioid therapy about half the patients experience an unacceptable balance between side effects and pain relief. According to research in cancer pain, a switch to methadone may improve pain control in these patients. However, there are several areas of uncertainty related to this switch in CNMP patients. It has not been evaluated in prospective studies with long-term follow up and both increased QTc time (QT time adjusted for heart rate) and autoinduction of methadone metabolism during long term treatment have been indicated in other patient populations.Research questionsHRQoL assessment methodology in CNMP patients:I. Is the EORTC QLQ-C30 a valid alternative to the SF-36 for assessment of HRQoL in CNMP patients?Comparison of HRQoL scores between patient groups:II. How is the HRQoL of CNMP patients admitted to multidisciplinary pain centre treatment compared to the HRQoL of palliative cancer patients?Opioid switching from morphine to methadone in CNMP patients with an unacceptable balance between pain control and side effects during morphine therapy:III. What are the effects on pain control, HRQoL, cognitive functioning and patient preference?IV. What is the effect on QTc time?V. Are methadone serum concentrations stable during long term treatment and are there interindividual differences in opioid metabolism?MethodsHRQoL data were collected from 288 CNMP patients admitted to multidisciplinary pain treatment. These data were used for psychometric validation of the EORTC QLQ-C30 HRQoL questionnaire and for comparison of HRQoL with palliative cancer patients. Twelve patients with unacceptable balance between pain control and side effects during morphine treatment for CNMP switched to methadone. Pain, HRQoL, cognitive functioning, opioid serum concentrations and QTc were evaluated at baseline and one, two, six and 13 weeks and nine months later.ResultsInternal consistency was below 0.70 for five of nine EORTC QLQ-C30 multi-item scales. Large floor or ceiling effects were seen for several scales. These weaknesses do not disrupt the picture of overall acceptable psychometric properties in this population.Compared to palliative cancer patients, patients with CNMP reported poorer global quality of life and cognitive functioning and more pain, sleep disturbances and financial difficulties as well as equally poor physical, social and emotional functioning and equally high levels of diarrhoea, dyspnoea and fatigue.Seven patients preferred long-term (> nine months) treatment with methadone and reported reduced pain and improved functioning while cognition was not improved. On the other hand one patient experienced sedation requiring naloxone and four patients were switched back to morphine due to poor pain control, drowsiness or sweating. Mean increase in QTc was 0.020 seconds. Serum concentrations of methadone and its metabolite EDDP were stable from the end of dose titration and during the nine months.Conclusions-The EORTC QLQ-C30 is a valid alternative to the SF-36 for HRQoL assessment in CNMP patients.-CNMP patients admitted to multidisciplinary pain centres report as poor HRQoL as palliative cancer patients.-Opioid switching to methadone causes improved pain control and HRQoL in some patients but is not beneficial to all patients and poses a risk of serious sedation.

Risk factors for acute renal failure requiring dialysis after surgery for congenital heart disease in children

Abstract: Background: Limited data exist on the risk factors for acute renal failure (ARF) following cardiac surgery in children with congenital heart disease. This cohort study was conducted to examine this subject, as well as changes in the incidence of ARF from 1993 to 2002, the in-hospital mortality and the time spent in the intensive care unit (ICU). Methods: One thousand, one hundred and twenty-eight children, operated on for congenital heart disease between 1993 and 2002, were identified from our prospectively collected ICU database to obtain data on potential risk factors. Results: A total of 130 children (11.5%) developed ARF after surgery. A young age [≥1.0 vs. <0.1 year; odds ratio (OR), 0.23; 95% confidence interval (CI), 0.12–0.46], high Risk Adjusted Classification of Congenital Heart Surgery (RACHS-1) score (OR, 2.72; 95% CI, 1.66–4.45) and cardiopulmonary bypass (CPB) (<90 min vs. none; OR, 2.68; 95% CI, 1.03–6.96; ≥90 min vs. none; OR, 12.94; 95% CI, 5.46–30.67) were independent risk factors for ARF. The risk of ARF decreased during the study period. Children with ARF spent a significantly longer time in the ICU (2–7 days vs. <2 days, P = 0.002; ≥7 days vs. <2 days, P < 0.001) compared with non-ARF patients, and showed increased in-hospital mortality (20% vs. 5%, P < 0.001). Conclusion: A young age, high RACHS-1 score and CPB were independent risk factors for ARF after surgical procedures for congenital heart disease in children. The risk of ARF decreased during the study period. Children with severe ARF spent a longer time in the ICU, and the mortality in ARF patients was higher than that in non-ARF patients.

Comparison of electrical velocimetry and thermodilution techniques for the measurement of cardiac output

Abstract: Aim: To compare a new method of non-invasive determination of cardiac output based on electrical velocimetry (EV-CO) with invasive thermodilution methods. Methods: Fifty critically ill patients were enrolled into the study. EV-CO was compared with cardiac output measured by a pulmonary artery catheter (PA-CO) in one group (n= 25) and by a femoral artery catheter (PiCCO-CO) in a second group (n= 25), by simultaneous measurements. Standard electrocardiography electrodes were used for non-invasive measurements, and EV-CO was calculated using the Bernstein–Osypka equation. The invasive measurements of PA-CO and PiCCO-CO were made by the injection of iced 0.9% saline and the recording of thermodilution curves. Results: The precision values of EV-CO, PA-CO and PiCCO-CO measurements were ± 0.46 [95% confidence interval (95% CI), ± 0.06], ± 0.57 (95% CI, ± 0.09) and ± 0.48 l/min (95% CI, ± 0.08 l/min), respectively. The mean differences between EV-CO and PA-CO or PiCCO-CO were –0.05 ± 0.71 and 0.22 ± 0.78 l/min, respectively. The lower and upper limits of agreement for the comparison of EV-CO with PA-CO were −1.47 and 1.37 l/min (95% CI, ± 0.25 l/min), respectively. In the comparison of EV-CO and PiCCO-CO, lower and upper limits of –1.34 and 1.78 l/min (95% CI, ± 0.27 l/min) were found. The percentage errors between EV-CO and PA-CO or PiCCO-CO were 26.5% and 26.4%, respectively. Conclusions: The values of cardiac output were statistically comparable between the groups. Therefore, electrical velocimetry is a suitable method to evaluate haemodynamic variables with clinically acceptable accuracy.

Prediction of post-operative pain by an electrical pain stimulus.

Abstract: Background: Treatment of post-operative pain is still a significant problem. Recently, interest has focused on pre-operative identification of patients who may experience severe post-operative pain in order to offer a more aggressive analgesic treatment. The nociceptive stimulation methods have included heat injury and pressure algometry. A simple method, Pain Matcher® (PM), using electrical stimulation, is validated for pain assessment, but has not been evaluated as a tool for prediction of post-operative pain. Our aim was to assess the predictive value of pre-caesarean section pain threshold on intensity of post-caesarean section pain using the PM. Patients and methods: Thirty-nine healthy women scheduled for elective caesarean section were studied. The anaesthetic/analgesic procedures included spinal anaesthesia, paracetamol, diclofenac, controlled-release (CR) oxycodone and morphine on request. Pre-operatively, the sensory and pain thresholds were measured using the PM. Post-operatively, a midwife, blinded for pre-caesarean pain threshold assessments, assessed the pain at rest and during mobilization every 12 h for 2 days. Consumption of analgesics was also recorded. Results: Pre-operative pain threshold correlated significantly with post-caesarean pain score (VAS) at rest and mobilization: [Spearman’s rho =–0.65 (–0.30 to –0.75), P < 0.01] and [Spearman’s rho =–0.52 (–0.23 to –0.72), P < 0.01], respectively. There was no significant correlation between pre-operative PM assessment of sensory threshold and post-operative pain. Conclusion: Electrical pain threshold before caesarean section seems to predict the intensity of post-operative pain. This method may be used as a screening tool to identify patients at high risk of post-operative pain.

Predictive value of six risk scores for outcome after surgical repair of hip fracture in elderly patients

Abstract: Background: Hip fracture surgery is associated with high post-operative mortality and poor functional results: the excess mortality is 20% in the first year; of those patients who survive, only 50% recover their previous ability to walk. The purpose of this study was to assess the predictive value of six functional status and/or surgical risk scoring systems with regard to serious complications after hip fracture surgery in the elderly. Methods: We performed a prospective study of a consecutive series of 232 patients (aged 65 years or older) undergoing hip fracture surgery. We pre-operatively applied: The American Society of Anesthesiologists classification, the Barthel index, the Goldman index, the Physiological and Operative Severity Score for the enUmeration of Mortality and Morbidity (POSSUM) scoring system, the Charlson index and the Visual Analogue Scale for Risk (RISK-VAS) scale. These scales were evaluated with respect to three variables: incidence of serious complications, the ability to walk after a 3-month period and 90-day survival. The predictive value of the different scales was assessed by the calculated area under a receiver operating characteristic curve. Results: The RISK-VAS scale, the POSSUM scoring system and the Charlson index reached a sufficient predictive value with regard to serious post-operative complications. The Barthel index and the RISK-VAS scale were those most useful for predicting ambulation at 3 months. None of the scales proved to be capable of predicting 90-day mortality. Conclusions: A simple index such as the RISK-VAS scale was the best predictor of serious post-operative complications. The functional level before the fracture, measured with the Barthel index, had a major influence on the ambulation recovery.

Post-operative recovery profile after laparoscopic cholecystectomy : a prospective, observational study of a multimodal anaesthetic regime

Abstract: Background: Laparoscopic cholecystectomy is now often an ambulatory procedure, but dependent on short-term post-operative complaints of pain and post-operative nausea and vomiting (PONV). The efficacy of post-anaesthesia care units (PACUs) is therefore important to facilitate return to normal functions. We investigated the feasibility and efficacy of a standardized, evidence-based anaesthesia/analgesic regime to identify residual problems in the early post-operative phase. Methods: One hundred and thirty-four consecutive patients admitted for elective laparoscopic cholecystectomy at Hvidovre University Hospital between 15 March and 30 September 2005 were included in the study. The standardized, evidence-based regime consisted of total intravenous (i.v.) anaesthesia (propofol-remifentanil), well-defined fluid therapy, dexamethasone, ketorolac, ondansetron, sufentanil and incisional bupivacaine intra-operatively, and in the PACU on demand (prn) administration of sufentanil, morphine, paracetamol, ondansetron, droperidol, oral fluids and oxygen (if SpO2 < 93%) with PACU discharge using a modified Aldrete score. Results: Protocol violations were moderate and occurred unsystematically, 8% had medical violations and 10% did not receive the pre-planned fluid amount. Severe PONV was seen in 2%. Thirteen per cent experienced severe pain, and the presence of any pain and/or PONV were predictors of an extended PACU stay. Mean oxygen demand was 46 min (range, 0–300 min), which influenced time to discharge (mean, 88 min). There were on average 2.7 treatment interventions (range, 0–11) before discharge. Conclusion: An evidence-based, multimodal approach to the anaesthetic/analgesic management in laparoscopic cholecystectomy is feasible and advantageous in the early post-operative phase. Pain and PONV are predictors of a complicated recovery profile and deserve further attention. Transient oxygen desaturations postpone discharge from the PACU, but the clinical significance of this fact is questionable.

Clinical practice and routines for day surgery in Sweden: results from a nation-wide survey

Abstract: Background: Day surgery is common in paediatric surgical practice. Safe routines including parental and child information in order to optimise care and reduce anxiety are important. Most day surgery units are not specialised in paediatric care, which is why specific paediatric expertise is often lacking.Methods: We studied the practice of paediatric day surgery in Sweden by a questionnaire survey sent to all hospitals, obtaining an 88% response rate. Three specific paediatric cases were enquired for in more detail.Results: The proportion of paediatric day surgery vs. in-hospital procedures was 46%. Seventy-one out of 88 responding units performed paediatric day surgery. All units had anxiolytic pre-medication as a routine in 1–6-year-olds, and in 7–16-year-olds at 60% of the units. Most units performed circumcision and adenoidectomy, while 33% performed tonsillectomy. Anaesthesia induction was intravenous in older children, and also in 1–6-year-olds at 50% of the units. Parental presence at induction was mandatory. Post-operatively, 93% of units routinely assessed pain. Paracetamol and NSAIDs were the most common analgesics, as monotherapy or combined with rescue medication in the recovery as IV morphine. At 42% of units, take-home bags of analgesics were provided, covering 1–3 days of treatment. Pain was the most frequent complaint on follow-up. Micturition difficulties were common after circumcision, nausea after adenoidectomy and nutrition difficulties after tonsillectomy.Conclusions: In Sweden, most day surgery units perform paediatric surgery, most children receive pre-medication, anaesthesia is induced IV and take-home analgesics paracetamol and or NSAIDs are often provided. Still, pain is a common complaint after discharge.

Combined photoplethysmographic monitoring of respiration rate and pulse: a comparison between different measurement sites in spontaneously breathing subjects.

Abstract: Background: The non-invasive photoplethysmographic (PPG) signal reflects blood flow and volume in a tissue. The PPG signal shows variation synchronous with heartbeat (PPGc), as used in pulse oximet ...

The post-operative analgesic effects of a combination of gabapentin and paracetamol in patients undergoing abdominal hysterectomy: a randomized clinical trial.

Abstract: Background: The aim of the present study was to compare the effects of a combination of gabapentin and paracetamol with gabapentin alone and placebo on post-operative pain and morphine consumption. Methods: Seventy-five ASA I–II patients undergoing abdominal hysterectomy were included in the study and randomly divided into three groups. Placebo capsules (Group I, n= 25), 1200 mg of gabapentin (Group II, n= 25), or 1200 mg of gabapentin and 20 mg/kg paracetamol in combination (Group III, n= 25) were administered 1 h prior to surgery. Anaesthesia was standardized for all patients. Non-invasive arterial pressure, heart rate, respiratory rate, peripheral oxygen saturation, morphine consumption, nausea and vomiting, visual analogue scale-pain intensity scores (VAS-PI) and sedation scores were recorded at 1, 2, 4, 6 and 24 h following the operation. Results: Morphine consumption at 24 h was 66.60 ± 11.49 mg, 42.74 ± 12.33 mg and 30.50 ± 11.55 mg, respectively, in groups I, II and III (P < 0.05). Post-operative VAS-PI scores at movement and at rest were decreased with gabapentin and even more with a combination of gabapentin and paracetamol. Post-operative sedation scores were higher in groups II and III during the initial 4 h while these scores were higher in group I at 24 h. Conclusions: The single dose of gabapentin as well as a combination of gabapentin and paracetamol decreased the opioid requirement and increased the patients’ satisfaction post-operatively.

Job satisfaction, work ability and life satisfaction among Finnish anaesthesiologists

Abstract: Background: Organizational changes and relative growth of the ageing population together with related health problems seem to have increased stressfulness in the work of anaesthesiologists. However, little is known about their work-related well-being and the factors through which their situation could be improved. Methods: A cross-sectional questionnaire study of the level and the determinants of job satisfaction, work ability and life satisfaction among female and male anaesthesiologists involved 258 Finnish anaesthesiologists working full time (53% men). Results: The respondents had fairly high job satisfaction, work ability and life satisfaction. No gender differences appeared in these well-being indicators, but their determinants differed by gender. Job satisfaction was only associated with work-related factors in both genders: with job control in women and with job control and organizational justice in men. Work ability correlated with job control and health in both genders and with family life in women. Life satisfaction correlated with individual- and family related factors such as social support and family problems in both genders. Life satisfaction correlated with physical workload in men and health in women. Women had less job control, fewer permanent job contracts and more domestic workload than men. Conclusions: Job control and organizational justice were the most important determinants in work-related well-being. Work-related factors were slightly more important correlates of well-being in males, and family life seems to play a larger role in the well-being of female anaesthesiologists. Organizational and gender issues need to be addressed in order to maintain a high level of well-being among anaesthesiologists.

Effect of thoracic epidural analgesia on gastric blood flow after oesophagectomy

Abstract: Laboratoire d’Epide´miologie et de Statistiques, Faculte´deMe´decine de Marseille, Marseille, FranceBackground: The oesophagectomy procedure includes the for-mation of a gastric tube to re-establish the continuity of thegastrointestinal tract. The effect of thoracic epidural analgesia(TEA) on gastric mucosal blood flow (GMBF) remains unknownin clinical practice. The aim of this prospective observationalstudywastoassess themicrocirculatorychanges inducedbyTEAin the early post-operative course.Methods: Eighteen consecutive patients who underwent radicaloesophagectomy with en-bloc resection and two-field lymphade-nectomy for oesophageal cancer, and benefited from TEA duringthe post-operative course, were studied prospectively, and com-paredwith nine patients who declined theuse of TEAin thesameperiod (control group). GMBF was measured using a laserDoppler flowmeter in three consecutive time periods (beforeand after 1 and 18 h of TEA infusion). Post-operative monitoringalso included the measurement of arterial pressure, cardiac out-put, gas exchange and intrathoracic blood volume index.Results: Afterthefirstand18thhourofinfusion,TEAinducedanincrease in GMBF compared with baseline and the control group.The mean arterial pressure and intrathoracic blood volume indexdecreasedafterthefirsthourofTEAinfusionwithnoinfluenceonthe cardiac index.Conclusions: This clinical study demonstrates that TEA im-proves the microcirculation of the gastric tube in the early post-oesophagectomy period. The clinical relevance of TEA in thissetting should be validated in larger studies focusing on theclinical outcome following oesophagectomy.

Anti-inflammatory effects of sevoflurane and mild hypothermia in endotoxemic rats.

Abstract: BACKGROUND Volatile anesthetics and hypothermia attenuate the inflammatory response. We aimed to compare the anti-inflammatory effects of sevoflurane and mild hypothermia during experimental endotoxemia in the rat. METHODS Anesthetized, ventilated Sprague-Dawley (SD) rats were randomly treated as follows (n = 6 per group): lipopolysaccharide (LPS) only, animals received LPS [LPS 5 mg/kg, intravenously (i.v.)] with no further treatment. In the LPS-hypothermia group, rats were cooled down to a temperature of 33 degrees C 15 min after LPS-injection (LPS 5 mg/kg i.v.). In animals of the LPS-sevoflurane group, sevoflurane inhalation (1 MAC) was initiated 15 min after induction of endotoxemia. The LPS-sevoflurane-hypothermia group received combined sevoflurane and hypothermia 15 min after induction of endotoxemia. A Sham group served as control without endotoxemia or treatment. After 4 h of endotoxemia, plasma levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and IL-10 were measured. Alveolar macrophages (AM) were ex vivo cultured for nitrite assay. RESULTS Inhalation of sevoflurane significantly attenuated plasma levels of TNF-alpha (-60%, P < 0.05) and IL-1beta (-68%, P < 0.05) as compared with the LPS-only group. Hypothermia and its combination with sevoflurane significantly reduced TNF-alpha levels (-46% and -58%, each P < 0.05), but not IL-1beta. Application of mild hypothermia and also its combination with sevoflurane resulted in a significant increase in plasma IL-10 as compared with endotoxemic controls. Nitrite release from AM was found to be significantly suppressed by sevoflurane (-83%), hypothermia (-73%) and by the combination of both (-67%) (P < 0.05, each). CONCLUSION Our data suggest that sevoflurane and mild hypothermia attenuate the inflammatory response during endotoxemia in vivo thus contributing to their beneficial role in clinical organ protection.

Inhaled iloprost to control pulmonary artery hypertension in patients undergoing mitral valve surgery: a prospective, randomized-controlled trial

Abstract: Background: Pulmonary hypertension (PHT) is common in patients undergoing mitral valve surgery and is an independent risk factor for the development of acute right ventricular (RV) failure. Inhaled iloprost was shown to improve RV function and decrease RV afterload in patients with primary PHT. However, no randomized-controlled trials on the intraoperative use of iloprost in cardiac surgical patients are available. We therefore compared the effects of inhaled iloprost vs. intravenous standard therapy in cardiac surgical patients with chronic PHT. Methods: Twenty patients with chronic PHT undergoing mitral valve repair were randomized to receive inhaled iloprost (25mg) or intravenous nitroglycerine. Iloprost was administered during weaning from cardiopulmonary bypass (CPB). Systemic and pulmonary haemodynamics were assessed with pulmonary artery catheterization and transoesophageal echocardiography. Milrinone and/or inhaled nitric oxide were availa ble as rescue medication in case of failure to wean from CPB. Results: Inhaled iloprost selectively decreased the pulmonary vascular resistance index after weaning from CPB *

Overtriage in trauma - what are the causes?

Abstract: Background: Different criteria are employed to activate trauma teams. Because of a growing concern about overtriage, the objective of this study was to investigate the performance of our trauma team’s activation protocol. Methods: Injured patients with trauma team activation (TTA), admission to an intensive care unit or surgical intermediate care unit with a trauma diagnosis, or trauma-related death in the emergency department were investigated retrospectively from 1 January 2004 to 31 December 2005. Different TTA criteria were analysed with respect to sensitivity, positive predictive value (PPV) and overtriage (1 – PPV). Results: Eight hundred and nine patients were included, 185 (23%) of whom had an Injury Severity Score (ISS) of more than 15. The performance of our protocol showed a sensitivity of 87%, PPV of 22% and overtriage of 78%. The mechanism of injury as a TTA criterion had a sensitivity of 14%, PPV of 7% and overtriage of 93%. Physiological/anatomical criteria and interfacility transfer showed higher PPV and less overtriage. Undertriage (no TTA despite ISS > 15) was identified in 23 patients (13%), 18 of whom were hospital transfers. Conclusion: A TTA protocol based on physiological, anatomical and interfacility transfer criteria seems to yield a higher precision than, in particular, that based on mechanism of injury criteria. Because of substantial overtriage in our hospital, the TTA protocol needs to be re-evaluated.

Pre-medication with intravenous clonidine suppresses fentanyl-induced cough

Abstract: Background: A reflex cough is often observed after an intravenous bolus of fentanyl. This study was conducted to determine whether pre-treatment with intravenous clonidine could effectively attenuate fentanyl-induced cough. Methods: Three hundred ASA I–II patients, aged between 18 and 80 years, undergoing various elective surgeries, were enrolled in this study. All patients were randomly assigned to one of two groups treated with intravenous clonidine 2 μg/kg (clonidine group) or the same volume of normal saline (control group). Intravenous fentanyl (2 μg/kg in 2 s) was injected 2 min after the clonidine or normal saline injection. Changes in the hemodynamics, auditory evoked potentials (AEPs) and Observer Assessment of Alertness/Sedation (OAA/S) rating scale were recorded before and 2 min after the clonidine or normal saline injection and 1 min after the fentanyl injection. The number of coughs 1 min after the fentanyl injection was also recorded. Results: Patients in the clonidine group showed a significantly lower incidence of cough than those in the control group (17.3% vs. 38.7%, respectively; P < 0.01). The blood pressure was lower in the clonidine group than in the control group. There were no significant differences in AEP or OAA/S rating scale. Conclusions: Pre-treatment with intravenous clonidine (2 μg/kg) suppressed the reflex cough induced by fentanyl, with mild hemodynamic changes. Therefore, intravenous clonidine may be a clinically useful method of suppressing fentanyl-induced cough.