Intensive Care Med (2002) 28: 864-869 The strong ion gap does not have prognostic value in critically ill patients in a mixed medical/surgical adult ICU R. J. Cusack1, , A. Rhodes1, P. Lochhead1, B. Jordan1, S. Perry1, J. A. S. Ball1, R. M. Grounds1 and E. D. Bennett1 (1) Department of Intensive Care Medicine, St George's Hospital, Blackshaw Road, London SW17 OQT, UK Presented in part at the 21st International Symposium on Intensive Care and Emergency Medicine, Brussels 2001 Abstract Objective. To examine whether the strong ion gap (SIG) or standard base excess corrected for abnormalities of serum chloride and albumin (BEUA) can predict outcome and to compare the prognostic abilities of these variables with standard base excess (SBE), anion gap (AG), pH, and lactate, the more traditional markers of acid-base disturbance. Design. Prospective, observational study. Setting. University teaching hospital, general adult ICU. Patients. One hundred consecutive patients on admission to the ICU. Measurements and results. The anion gap (AG) was calculated and corrected for abnormal serum albumin (AGcorrected). Serum lactate was measured and SBE, BEUA , SIG, and APACHE II scores calculated for each patient. 28-day survival was recorded. There was a significant difference between the mean APACHE II (P<0.001), SBE (P<0.001), lactate (P=0.008), AG (P=0.007), pH (P<0.001), and BEUA (P=0.009) of survivors and non-survivors. There was no significant difference between the mean SIG (P=0.088), SIDeff (P=0.025), and SID app (P =0.254) between survivors and non-survivors. The pH and SBE demonstrated the best ability of the acid-base variables to predict outcome (AUROC curves 0.72 and 0.71, respectively). Neither of these were as good as the APACHE II score (AUROC 0.76) Conclusion. Traditional indices of SBE, BEUA, lactate, pH, AG, and APACHE II all discriminated well between survivors and non-survivors. In this group of patients the SIG, SIDeff, and SIGapp appear to offer no advantage in prediction of outcome and their use as prognostic markers can therefore not be advocated. Keywords. Strong ion gap - Standard base excess - Prognostic indicators - Acid-base disturbance PAIN®, Vol. 98 (3) (2002) pp. 269-275 © 2002 International Association for the Study of Pain. Published by Elsevier Science B.V. All rights reserved. PII: S0304-3959(02)00019-2 No pain, no gain: clinical excellence and scientific rigour - lessons learned from IA morphine Eija Kalso a * eija.kalso@helsinki.fi , Lesley Smith b, Henry J. McQuay b and R. Andrew Moore b a Pain Clinic, Department of Anaesthesia and Intensive Care, Helsinki University Hospital, P.O. Box 340, Helsinki FIN-00029 HUS, Finland b Pain Research and Nuffield Department of Anaesthetics, University of Oxford, Oxford Radcliffe Hospital, The Churchill, Headington, Oxford OX3 7LJ, UK Received 12 March 2001; received in revised form 19 December 2001; accepted 8 January 2002 Abstract The effectiveness of intra-articular (IA) morphine in arthroscopic procedures of the knee joint was analysed in all randomised and controlled trials that included injections of morphine and placebo into the knee joint, and where the data were analysable. Sensitivity of the studies and effectiveness were analysed for three different periods: immediate (02h), early (2-6h) and late (6-30h). Sensitivity for each period was assumed if pain intensity was at least 30% of the maximum of 100 on the visual analogue scale in the placebo group. Six different doses (1-10mg) of IA morphine were compared with placebo. The injections were made at the end of surgery, before the arthroscope was removed from the joint. In the immediate period 7/15 sensitive trials were positive, in the early period 8/12 sensitive trials were positive and in the late period 10/13 sensitive trials were positive. Most positive studies had used higher doses (3-5mg) compared with negative studies that had mainly used 1mg. Two studies using patient controlled analgesia consumption of analgesics as an outcome were also positive. The only sensitive study of four dose-response comparisons indicated that 5mg of IA morphine was more effective than 1mg. The only sensitive study of three cross-route comparisons showed no difference between 5mg of IA and 5mg of intra-muscular morphine. All insensitive trials, including placebo (except two individual comparisons), cross-route and dose-response comparisons, were negative. The analysis of sensitive studies indicates that 5mg of IA morphine injected into the knee joint provides postoperative pain relief for up to 24h. A minimum of 30% of the maximum possible pain intensity is needed for an analgesic effect to be detected in a study. Keywords: Intra-articular; Knee joint; Morphine; Systematic review * Corresponding author. Tel.: +358-9-47175885; fax: +358-9-47175641 Intensive Care Med (2002) 28: 917-924 Influences on physicians' choices of intravenous colloids Michael S. Miletin1, Thomas E. Stewart1, 2, and Peter G. Norton3 (1) Department of Medicine, University of Toronto, Mount Sinai Hospital, 600 University Avenue, Toronto, Ontario, Canada M5G 1X5 (2) Critical Care Medicine Programme, Critical Care Unit, Mount Sinai Hospital, 600 University Avenue, Suite 1818, Toronto, Ontario, Canada M5G 1X5 (3) Department of Family Medicine, University of Calgary, UCMC-Sunridge, 3465 26th Avenue NE, Calgary, Alberta, Canada T1Y 6L4 Funding for this project was provided by Bayer Corporation, Biologic Products Division. Abstract Objectives. Controversy over the optimal intravenous fluid for volume resuscitation continues unabated. Our objectives were to characterize the demographics of physicians who prescribe intravenous colloids and determine factors that enter into their decision to choose a colloid. Design. Questionnaire with 61 items. Participants and setting. Ten percent (n=364) of frequent intravenous fluid prescribers in the province of Ontario, Canada. Results. The response rate was 74%. Colloid use in the past year was reported by 79% of the responding physicians. Important reasons for choosing a colloid included blood loss and manipulation of oncotic pressure. Physicians tended to prefer either albumin or pentastarch, but no important reasons were found for choosing between the two. Albumin with or without crystalloid was preferred in 5/13 scenarios by more than 50% of the respondents, whereas pentastarch was not favored by more than 50% of respondents in any scenario. Physicians practising in critical care areas and teaching hospitals generally preferred pentastarch to albumin. Physicians reporting pentastarch as representing greater than 90% of total colloid use were more likely to have been visited by a drug detailer for pentastarch than those who used less synthetic colloid (54 vs 22%, p<0.001). Conclusions. The majority of physicians surveyed prescribe colloid products and the reported use of albumin and pentastarch has a bimodal distribution. Although albumin appeared to be preferred in more clinical niches, most physicians did not state reasons for choosing between products. Marketing, specialty, location of practice and clinical scenario appear to play significant roles in the utilization of colloid products. Keywords. Questionnaire - Colloids - Albumin - Pentastarch - Intravenous fluids (Chest. 2002;122:192-196.) © 2002 American College of Chest Physicians Use of Inspiratory Muscle Strength Training to Facilitate Ventilator Weaning* A Series of 10 Consecutive Patients A. Daniel Martin, PhD, PT; Paul D. Davenport, PhD; Amy C. Franceschi, PT and Eloise Harman, MD, FCCP * From the Departments of Physical Therapy (Dr. Martin), Physiological Sciences (Dr. Davenport), and Medicine (Dr. Harman), University of Florida, Gainesville, FL, and the Department of Physical Therapy (Ms. Franceschi), Shands Hospital at the University of Florida, Gainesville, FL. Correspondence to: Daniel Martin, PhD, PT, Box 100154, Health Science Center, Gainesville, FL 32610; e-mail: dmartin@hp.ufl.edu Background and purpose: We instituted a low-repetition, high-intensity inspiratory muscle strength training (IMST) program and progressively longer spontaneous breathing periods (SBPs) in a group of medically complex patients who were dependent on mechanical ventilation (MV) and had failed to wean. Case descriptions: IMST was provided to 10 consecutive patients (four men, six women; mean [± SD] age, 59 ± 15 years) who had failed to wean from MV by conventional methods for 7 days. Prior to initiating IMST, patients had received MV support for a mean of 34 ± 31 days. Daily IMST consisted of four sets of six breaths through a threshold inspiratory muscle trainer that had been set at an intensity to yield an exertion rating of 6 to 8 of a maximal value of 10. At the start of IMST, patients were tolerating 2.1 ± 3.4 consecutive hours of SBPs. The duration of the SBPs was increased daily, as tolerated. Patients were considered to have been weaned from MV when they were able to breathe without MV support for 24 consecutive hours. Outcomes: After 44 ± 43 days of IMST, 9 of 10 patients were weaned from MV. The initial IMST pressure was 7 ± 3 cm H2O, and it was increased to 18 ± 7 cm H2O (p < 0.05). Discussion: These results indicate that an IMST protocol that produces significant increases in threshold training pressure, in combination with progressive SBPs, aids in weaning patients from MV. Although promising, these preliminary observations must be tested in a controlled trial. Key Words: respiratory muscle training • ventilator dependence • ventilator weaning (Chest. 2002;122:140-145.) © 2002 American College of Chest Physicians Noninvasive Evaluation of Pulmonary Capillary Wedge Pressure by BP Response to the Valsalva Maneuver* Daniel Weilenmann, MD; Hans Rickli, MD; Ferenc Follath, MD; Wolfgang Kiowski, MD and Hans Peter Brunner-La Rocca, MD * From the Division of Cardiology (Drs. Weilenmann, Rickli, Kiowski, and Brunner-La Rocca) and the Department of Internal Medicine (Dr. Follath), University Hospital, Zurich, Switzerland. Correspondence to: Daniel Weilenmann MD, Division of Cardiology, University Hospital, Petersgraben 4, CH-4031 Basel, Switzerland; e-mail: dweilenmann@uhbs.ch Study objectives: To determine the BP response to the Valsalva maneuver (VM) at baseline and after changes in therapy and to compare this response to the invasively measured pulmonary capillary wedge pressure (PCWP). Design: Comparison of the BP response to the VM with invasively measured PCWP. In a subset of patients, direct PCWP and pulse amplitude ratio (PAR) measurements were repeated (mean ± SD) 3.2 ± 4.5 months later after adjusting the therapy. Setting: Tertiary-care center. Patients: Forty-two stable patients (8 women; mean age, 58 ± 13 years) undergoing right heart catheterization who were in sinus rhythm. Measurements: PAR calculated between the end and the beginning of the VM using the last two beats and the first three beats of the straining phase and simultaneous measurement of PCWP. Results: There was a highly significant correlation between the invasively measured PCWP (range, 2 to 32 mm Hg) and the PAR (range, 0.28 to 1.15; R2 = 0.75; p < 0.001). In addition, changes of PCWP during follow-up (-16 to 13 mm Hg) were well-correlated (R2 = 0.93; p < 0.001; n = 11) with changes in PAR (-0.44 to 0.47). The administration of medication (eg, ß-blockers, amiodarone, angiotensin-converting enzyme inhibitor, and digoxin) did not influence the results. Conclusions: PCWP and changes during therapy can be estimated noninvasively by measuring the PAR during the VM with acceptable accuracy in stable patients with cardiac conditions. Thus, this method may be a useful tool in detecting an elevated PCWP and hemodynamic response to therapy. Key Words: congestive heart failure • pulmonary capillary wedge pressure • therapy • Valsalva maneuver Measurement and monitoring of neuromuscular blockade Aaron F. Kopman Department of Anesthesiology, New York Medical College, at Saint Vincent Catholic Medical Centers, Manhattan, USA CURRENT OPINION IN ANAESTHESIOLOGY 2002;15:415-420 Purpose of review For more than three decades, ‘experts’ in the clinical pharmacology of neuromuscular blocking agents have advocated routine intraoperative use of peripheral nerve stimulators as monitors of neuromuscular function. This advice is far from universally honored in practice. In part, this dichotomy between ‘accepted wisdom’ and actual day-to-day practice may stem from a failure to provide the clinician with a peripheral nerve stimulator that does not require subjective evaluation of evoked responses. For 99% of anesthetists, the train-of-four fade ratio is a parameter that they read about but cannot measure. This need no longer be the case. Recent findings Small battery operated units are now available that are relatively inexpensive, easy to set up, and provide objective measurement of the train-of-four ratio. Although agreement between the output of these acceleromyographic and piezoelectric sensors with such ‘gold standard’ technologies as mechanomyography and electromyography is not absolute, it is probably adequate for clinical case management. Summary It is my hope (and I have no financial interest in any of the cited devices) that the present review will encourage further distribution of objective monitors of neuromuscular function. Keywords neuromuscular; monitoring; twitch; tetanus; train-of-four; nondepolarizing block Correspondence to Aaron F. Kopman, MD, Vice-Chairman, Department of Anesthesiology, New York Medical College, at Saint Vincent Catholic Medical Centers, Manhattan, 170 West 12th Street (Room NR408), New York, NY 10011, USA. Tel: +1 212 604 2636; fax: +1 212 604 2637; e-mail: Akopman@rcn.com Abbreviations FEV1 FIV1 PNS TOF : forced expiratory volume in 1 s : forced inspiratory volume in 1 s peripheral nerve stimulator train-of-four Airway management outside the operating room Joseph R. Brimacombea; Christian Kellerb a Department of Anaesthesia and Intensive Care, University of Queensland and James Cook University, Cairns Base Hospital, Cairns, Australia and bDepartment of Anaesthesia and Intensive Care Medicine, Leopold-Franzens University, Innsbruck, Austria CURRENT OPINION IN ANAESTHESIOLOGY 2002;15:461-465 The choice of airway device for resuscitation depends on the skill of the user, the equipment available, the conscious state of the patient, the location of the patient and the probable cause of the cardiorespiratory arrest. Extraglottic airway devices are recommended by the European and American Resuscitation Councils for use when intubation skills are lacking. In this review, we discuss recent research relevant to the use of extraglottic airway devices in resuscitation. Correspondence to Professor J Brimacombe, Department of Anaesthesia and Intensive Care, University of Queensland and James Cook University, Cairns Base Hospital, The Esplanade, Cairns 4870, Australia; Fax: +61 7 40311628; e-mail: jbrimacombe@austarnet.com.au Abbreviations COPA ETC LMA LTA Cuffed Oropharyngeal Airway Esophageal Tracheal Combitube Laryngeal Mask Airway Laryngeal Tube Airway Acta Neurochirurgica Table of Contents Abstract Supplement 81 (2002) pp S89-S91 ICP is Lower During Propofol Anaesthesia Compared to Isoflurane and Sevoflurane K. D. Petersen, U. Landsfeldt, G. E. Cold, C. B. Pedersen, S. Mau, J. Hauerberg, and P. Holst Summary. Objectives. Propofol is a cerebral vasoconstrictor while inhalation anaesthetics like isoflurane and sevoflurane act as cerebral vasodilators in both animal and human studies. This difference of action upon cerebral vessels might implicate a lower ICP during propofol anaesthesia. Cerebral metabolism is decreased by all three anaesthetics. In a prospective, randomised multicenter study ICP was compared during anaesthesia with propofol, isoflurane and sevoflurane. Methods. 117 patients subjected to elective craniotomy for supratentorial tumour. Propofol: N = 41; isoflurane: N = 38; sevoflurane: N = 38. Nitrous oxide was omitted and all anaesthetics were supplemented with a continuous infusion of fentanyl. ICP was measured subdurally after removal of the bone flap. MABP, CPP, PCO2, AVDO2, rectal temperature, tumour size and midline shift were registered too. Statistics: Kruskal-Wallis Variance on Ranks. All values in medians with range. P < 0.05 was considered significant. Results. ICP (mmHg): propofol 7 (1 –20), isoflurane 12 (1 –29), sevoflurane 11 (–32). ICP was significantly lower in the propofol group compared to the isofluane and sevoflurane groups. CPP (mmHg): propofol 80 (45 –104), isoflurane 60 (32 –84), sevoflurane 63 (44 –77). CPP was significantly higher in the propofol group compared to the isoflurane and sevoflurane groups. AVDO2 (mmol/l): propofol 3.1 (0.9 –5.1), isoflurane 2.5 (1.1 –4.5), sevoflurane 2.6 (0.8 –4.1). AVDO2 was significantly higher in the propofol group compared to the isoflurane and sevo-flurane groups. No significant differences in PCO2, rectal temperature, tumour size and midline shift were found. Conclusions. Subdural ICP is significantly lower during propofol anaesthesia compared to isoflurane and sevoflurane anaesthesia. CPP and AVDO2 are significantly higher during propofol anaesthesia compared to isoflurane and sevoflurane anaesthesia. Keywords: Intracranial pressure, propofol, isoflurane and sevoflurane.