Effect of preemptive intra-articular morphine and ketamine on pain after arthroscopic rotator cuff repair: a prospective, double-blind, randomized controlled study.

BACKGROUND: Rotator cuff tear is a leading etiology of shoulder pain and disability. Surgical treatment is indicated in patients with persistent pain who fail a trial of non-surgical treatment. Pain reduction following rotator cuff repair, particularly within the first 24-48 h, is a major concern to both doctors and patients. This study aimed to compare the postoperative antinociceptive additive effects of pre-incisional intra-articular (IA) ketamine when combined with morphine with two times the dose of morphine or saline. METHODS: In this prospective, randomized, double blind, controlled trial patients undergoing arthroscopic rotator cuff tear repair (ARCR) under general anesthesia were enrolled. Patients were randomly assigned to one of the three intervention groups. Twenty minutes prior to incision, morphine (20 mg/10 ml), ketamine (50 mg + morphine 10 mg/10 ml), or saline (0.9 % 10 ml) (n = 15/group), were administered to all patients. First 24 h postoperative analgesia consisted of intravenous patient controlled analgesia (IV-PCA) morphine and oral rescue paracetamol 1000 mg or oxycodone 5 mg. 24-h, 2-week and 3-month patient rated pain numeric rating scale (NRS) and analgesics consumption were documented. RESULTS: Patients' demographic and perioperative data were similar among all groups. The 24-h and the 2-week NRSs were significantly (p < 0.05) lower in both treatment groups compared to placebo, but were not significantly different between the two intervention groups. PCA-morphine and oral analgesics were consumed similarly among the groups throughout the study phases. CONCLUSIONS: Pre-incisional intra-articular morphine reduced pain in the first 2 weeks after arthroscopic rotator cuff repair. Further research is warranted to elucidate the optimal timing and dosing of IA ketamine and morphine for postoperative analgesic effects.

Ascites characterizes perioperative clinical indices better than preoperative body mass index. A study in orthotopic liver transplant candidates.

BACKGROUND: Preoperative body mass index (pre-BMI) affecting patients' recovery from orthotropic liver transplantation (OLT) is controversial. Pre-BMI measurements may be exaggerated by ascites. Aim of the study was the assessment of early outcome associated with pre-BMI and ascites. METHODS: Postoperative BMI values and ascites volumes of 206 patients undergoing OLT (2006-2007) were reviewed. RESULTS: There were 141 preoperatively "non-obese" patients (pre-BMI ≤ 30 kg/m2) and 65 "obese" patients (pre-BMI >30 kg/m2). Demographics and model for end-stage liver disease scores were similar for both groups. The mean volume of ascites removed from the "non-obese" patients was significantly larger compared to the "obese" ones (P=0.018). Seventeen "obese" patients became "non-obese" postoperatively. The duration of anesthesia, ischemia, surgery, hemodynamic parameters, estimated blood loss and transfused products were similar for both groups. Ascites volumes correlated significantly (P<0.05) with various intraoperative indices but not pre-BMI. At 24 h postoperatively, the extubation rate was better for the "obese" group (99%) versus the "non-obese" group (93%, P=0.03). However, "non-obese" patients were extubated earlier than the "obese" both by 6 h (45% versus 22%, respectively, P<0.01) and by 12 h (88% versus 74%, respectively, P=0.012). The postoperative, but not the preoperative BMI, correlated with extubation rate ≤ 6 h (r=0.924, P=0.0001). No "obese" patients died <1 month postoperatively, compared to 9 "non-obese" patients (P<0.01). Intensive Care Unit and hospital stay were ~25% longer for the "obese" group. CONCLUSION: Pre-OLT BMI does not correlate with ascites or postoperative BMI, nor does it affect duration of ventilation, especially <6 h after surgery. These results dissociate ascites from pre- and post-OLT.

Metformin-associated lactic acidosis following acute kidney injury. Efficacious treatment with continuous renal replacement therapy.

INTRODUCTION: Metformin is a biguanide anti-hyperglycaemic drug. Metformin-associated lactic acidosis may sometimes be life-threatening. Continuous renal replacement therapy has been suggested as a method for resolving this extremely dangerous metabolic state. We describe the history of six patients admitted to the intensive care unit over a 28-month period in pre-shock conditions because of severe lactic acidosis, attributed to metformin-associated lactic acidosis, and successfully treated. METHODS: We reviewed the charts of six patients admitted to our intensive care unit between January 2008 and May 2010. After initial assessment, all patients were treated with continuous renal replacement therapy. Admission serum lactate and creatinine levels, pH, need for ventilatory and cardiovascular support, as well as continuous renal replacement therapy details and length of stay were reviewed. RESULTS: Admission pH levels of the six patients ranged between pH 6.63 and 7.0 and their serum lactate levels ranged between 12 and 27 mmol/l; the estimated creatinine clearance ranged between 6 and 24 ml min(-1) 1.73 m(-2) . All patients required vasoactive support and five required ventilatory support. Lactate levels decreased to near zero with continuous renal replacement therapy within 7-19 h in five of the patients whose intensive care unit length of stay ranged between 1 and 5 days. One patient's length of stay reached 11 days because of pneumonia, one died from multi-organ failure and another suffered permanent neurological damage following prolonged cardiopulmonary resuscitation before continuous renal replacement therapy was administered. All other patients recovered without sequellae. CONCLUSIONS: Accurate recognition of metformin-associated lactic acidosis and prompt initiation of haemodialysis are paramount steps towards rapid recovery. Large series reports and controlled studies may better determine the optimal duration and best dialysis technique in these patients.

Higher postoperative pain and increased morphine consumption follow pre- rather than post-incisional single dose epidural morphine.

BACKGROUND: Neuraxial administration of morphine is an effective way of controlling postoperative pain and reducing analgesic consumption. Some animal models have demonstrated that preemptive administration of neuraxial narcotics reduces pain, while others have revealed the contrary. In addition, there have been no consistent results in clinical settings. This double-blind, randomized study compared the effects of pre- vs. post-incisional administration of neuraxial morphine on postoperative pain perception and analgesic requirements over 48 hours following laparotomy for open colectomy under standardized general anesthesia. METHODS: Twenty patients received epidural morphine (3 mg) before the incision and saline after wound closure (MO1 group), and twenty patients received epidural saline before the incision and morphine after wound closure (MO2 group). Postoperatively, all patients received morphine boluses (1.5 mg) via intravenous patient-controlled analgesia (IV-PCA) and rescue doses of intramuscular diclofenac (75 mg) every 6 hours, as needed. RESULTS: MO1 patients used significantly (P<0.05) more morphine than the MO2 group during the first 24 postoperative hours and activated the PCA device more frequently throughout the 48-hour study period. The MO1 group was characterized by significantly (P<0.05) higher self-rated pain scores than the MO2 group throughout the study. The self-rated levels of sedation and satisfaction of the MO2 patients were also consistently better (P<0.05) than those of the MO1 patients, especially during the second postoperative day. CONCLUSION: Pre-incisional epidural morphine in patients undergoing open colonic surgery under general anesthesia was associated with more postoperative pain, a greater need for analgesics, and poorer patient satisfaction compared to post-incisional morphine administration.

Cuffed oropharyngeal airway (COPA) placement is delayed by wearing antichemical protective gear.

BACKGROUND: Airway management, the first step in resuscitation, may entail special difficulties in mass casualty situations, even in experienced hands. Of the available airway devices, the cuffed oropharyngeal airway (COPA) appears the easiest one to insert, allowing a hands-free anaesthesiologist. A study was undertaken to evaluate the success of airway control with COPA when anaesthetists wore either surgical attire or antichemical protective gear. METHODS: Twelve anaesthetists with 2-5 years of residency inserted COPA in 24 anaesthetised patients in a random crossover prospective manner. The duration of airway management was measured from the time the device was grasped to obtaining a normal capnography recording; time to proper fixation was also recorded. RESULTS: Time to COPA placement was significantly shorter when the anaesthetists wore surgical attire than when they wore protective gear (28 (10) s vs 56 (34) s, p<0.05). Time to proper fixation of the COPA to patients' faces also differed significantly (19 (14) s with surgical attire vs 34 (16) s with protective gear, p<0.05). First-time COPA insertion failure was statistically similar in both groups. There was no hypoxaemia. CONCLUSIONS: Antichemical protective gear slowed proper placement of COPA and its fixation compared with surgical attire. COPA may be a temporarily useful device in non-conventional settings, but functional reassessment is required when injured patients reach medical facilities.

Acute lung injury following pancreas ischaemia-reperfusion: role of xanthine oxidase.

BACKGROUND: Acute pancreatitis can lead to increased pulmonary vascular permeability and respiratory failure. Oxidants (and their generator, xanthine oxidase (XO)) play an important role in injuring the structural integrity of the pulmonary epithelium and endothelium, but their importance in the induction of acute lung injury following pancreas ischaemia-reperfusion (IR) has not been defined. MATERIALS AND METHODS: Rats (n = 48) received a regular or a tungsten (oxidoreductase inhibitor)-enriched diet for 14 days. Their isolated pancreases were then either perfused (controls) or made ischaemic (IR) for 40 min (12 replicates/group). This was followed by in-series pancreas plus normal isolated lung reperfusion for 15 min. Lungs only were subsequently perfused with the 15-min accumulated pancreas effluents for 45 min. RESULTS: Injury was induced in all IR pancreases as expressed by reperfusion pressure, wet-to-dry ratio and amylase and lipase concentrations. Tissue XO activity was high and reduced glutathione pool was low in the tungsten-free IR pancreases. Pulmonary plateau pressure increased by 46% and final PO(2)/FiO(2) decreased by 24%. Capillary pressure and weight rose two- to fourfold in lungs paired with IR non-treated pancreases. Twofold increases in bronchoalveolar lavage volume and contents, including XO, were also recorded in this group of lungs. Lungs exposed to tungsten-treated ischaemic pancreas effluents were minimally damaged and tissue XO content was low compared to controls. CONCLUSIONS: Ex-vivo acute pancreatitis induces acute lung injury via oxidants/antioxidants misbalance, which may be prevented by attenuating pancreas oxidative stress.

Methylene blue attenuates lung injury after mesenteric artery clamping/unclamping.

BACKGROUND: This controlled, experimental study was designed to assess the effects of intratracheal and intravenous methylene blue on reperfusion lung injury following superior mesenteric artery clamping/unclamping. MATERIALS AND METHODS: Superior mesenteric arteries of 144 anaesthetized adult male Wistar rats (n = 12/group) were clamped for 1 h. Ten minutes before unclamping, methylene blue or its vehicle was administered intratracheally or intravenously, followed by a 3 h-respiratory assessment and postexperimental assessment of survival. RESULTS: Intravenous 3 and 9 mg kg(-1) but not higher methylene blue doses, and intratracheal 6-mg kg(-1) but not lower doses, significantly (P < 0.05) reduced the 100% increase in plateau pressure, 30% reduction in PO(2)/FiO(2), fourfold augmented bronchoalveolar lavage-retrieved volume and the increased polymorphonuclear leukocytes/bronchoalveolar cells' ratio associated with unclamping of the superior mesenteric artery. Lung tissue polymorphonuclear leukocytes count, total xanthine oxidase activity and wet-to-dry-weight ratio were also normal in these dose-treated groups. These effective regimens were also associated with longer animal survival. CONCLUSIONS: Intratracheal methylene blue mitigates lung reperfusion injury following superior mesenteric artery clamping/unclamping at a similar magnitude as an intravenous regimen. This finding is a novel potential use of methylene blue in vivo.

Faecal sterol output is increased by arachidyl amido cholanoic acid (Aramchol) in rats.

Fatty acid-bile acid conjugates (FABACs) were shown recently to have important and multiple effects on cholesterol metabolism. In human fibroblasts, they were found to markedly enhance cholesterol efflux by an ATP-binding cassette transporter A1-dependent pathway. In C57L/J mice, they increased CYP7A1 activity and RNA expression, while decreasing moderately 3-hydroxy-3-methylglutaryl-CoA reductase activity. In C57L/J mice and in hamsters, they also decreased serum cholesterol levels, whereas in other animals, this effect was not seen in short-term experiments. In the present study, we investigated potential mechanisms of action of arachidyl amido cholanoic acid (Aramchol), with particular reference to biliary and faecal sterol outputs in rats. Supplementation with Aramchol at a dose of 150 mg x kg(-1) x day(-1) increased neutral sterol output by approx. 50%, while the faecal outputs of bile salts and total sterols increased by almost 2-fold. Biliary lipid outputs were not significantly different between the control and FABAC-supplemented animals. These findings indicate an overall catabolic effect of FABACs on body cholesterol.

Mannitol dose-dependently attenuates lung reperfusion injury following liver ischemia reperfusion: a dose-response study in an isolated perfused double-organ model.

We had previously studied different modes of prevention of liver ischemia-reperfusion (IR)-induced remote organ reperfusion injury, a challenge that remains partly unmet. We have now studied the capability of mannitol at different doses in abrogating liver IR-induced lung reperfusion injury in an isolated double-organ model. Rat livers ( n = 8/group) were perfused with Krebs-Henseleit solution (control) or made globally ischemic (IR) for 2 h, after which they were paired with normal lungs and "reperfused" together for 15 min. The lungs were then perfused alone with the accumulated Krebs for an additional 45 min. Another 4 control and 4 IR pairs were reperfused with Krebs containing mannitol at.22 mmol,.55 mmol,.77 mmol, or 1.1 mmol. Mannitol.22 mmol and 1.1 mmol failed to attenuate IR-lung injury as indicated by 50-95% increases in inspiratory and perfusion pressures and compliance reduction, a 70% increase in weight gain, and a 2-50-fold increase in bronchoalveolar lavage volume and content. Mannitol.55 mmol prevented all these abnormalities, and.77 mmol attenuated only changes in ventilatory parameters. The latter two treatments were also associated with a 50% reduction in xanthine oxidase activity and a 35-45% increase in the reduced glutathione tissue content compared with the nontreated IR-paired lungs. It is concluded that mannitol in a narrow therapeutic dose range can reduce oxidalive stress-induced lung damage that is related to liver IR.

The midazolam-induced paradox phenomenon is reversible by flumazenil. Epidemiology, patient characteristics and review of the literature.

BACKGROUND AND OBJECTIVE: Midazolam may occasionally precipitate hostility and violence instead of tranquility. We characterized these episodes, their rate of occurrence, the potential paradoxical responders and possible predisposing circumstances among patients undergoing lower body surgery under spinal or epidural anaesthesia and midazolam sedation. PATIENTS AND METHODS: Fifty-eight patients who fulfilled the study entry criteria and who underwent surgery within a 3-month period in a large metropolitan, university-affiliated hospital were enrolled. Sedation and restlessness in all patients were controlled by midazolam administered intravenously by the attending anaesthesiologist; these parameters were later objectively confirmed by recorded actigrams. If "paradoxical" events occurred, flumazenil 0.1 mg 10 s-1 was injected until the aberrant behaviour ceased. Patients with paradoxical reactions were later compared with matched control patients selected from the study group to identify epidemiological characteristics. RESULTS: The incidence of paradoxical events was 10.2% (six out of 58 patients, confidence limits 2.3-18.3%) and they occurred 45-210 min after sedation started; the only independent predictor was an age older than that of the entire study group. The mean cumulative and per weight doses of midazolam were similar for both the experimental and the study groups of patients: 7.3 +/- 2.8 to 10.1 +/- 3.6 mg, and 0.1 +/- 0.04 to 0.12 +/- 0.05 mg kg-1. Flumazenil 0.2-0.3 mg (range 0.1-0.5 mg) effectively stopped the midazolam-induced paradoxical activity within 30 s and surgery continued uneventfully. CONCLUSIONS: Flumazenil completely reverses midazolam-induced paradoxical reactions and they are more frequent in older patients.

Flumazenil improves cognitive and neuromotor emergence and attenuates shivering after halothane-, enflurane- and isoflurane-based anesthesia.

PURPOSE: To conduct a randomized, placebo-controlled, double-blinded, clinical experiment testing the hypothesis that flumazenil, a benzodiazepine antagonist, may affect recovery from halothane-, enflurane- and isoflurane-based anesthesia. METHOD: Patients who underwent surgery under N(2)O/O(2) plus halothane (n=100), enflurane (n=100) or isoflurane (n=70) anesthesia were administered flumazenil 1 mg or placebo upon emergence from anesthesia, and their postanesthesia vital signs, vigilance, neurological recovery, shivering, amnesia reversal, and general subjective feeling were assessed. RESULTS: A ten-point vigilance score showed better recovery of flumazenil-treated patients compared to those who received placebo (60-min after halothane anesthesia: 9.9 +/- 0.1 vs 9.5 +/- 0.2, P <0.01; after enflurane: 10 +/- 0 vs 9.4 +/- 0.2, P <0.01; after isoflurane: 10.0 +/- 0 vs 9.3 +/- 0.1, P <0.01). Halothane- and enflurane-flumazenil-treated patients (but not isoflurane) reached a better neurological score (2.97 +/- 0.05 or 3 +/- 0) compared to placebo (2.8 +/- 0.4 or 2.6 +/- 0.4, P <0.01), respectively. Reversal of amnesia was superior in the flumazenil group at 60 min and at 24 hr postsurgery, and more flumazenil patients rated recovery as "pleasant". Flumazenil patients shivered less than placebo patients despite their lower core temperature (at 30 min: halothane: 11% vs 28%, P <0.05; enflurane: 11% vs 30%, P <0.05; isoflurane: 17% for both groups). CONCLUSION: Flumazenil improves recovery of high cortical and neuromotor functions following halothane, enflurane and isoflurane anesthesia, reduces shivering and improves the overall quality of emergence, including patients' subjective feeling.

Dextromethorphan and dexmedetomidine: new agents for the control of perioperative pain.

Most traditional opioids and non-steroidal anti-inflammatory drugs that are used to control perioperative pain have substantial side effects. The number of choices in clinical use was recently increased by two promising groups of drugs: N-methyl-D-aspartate receptor antagonists and central alpha2 agonists. One N-methyl-D-aspartate antagonist, dextromethorphan, blocks the generation of central pain sensation that arise from peripheral nociceptive stimuli by moderating the activity of N-methyl-D-aspartate. It pre-empts the sensation of acute pain at doses of 30-90 mg without serious side effects, while reducing the amount of analgesics required perioperatively by 50%. It is available in oral form and has a confirmed lack of effect on haemodynamics and respiration. Dexmedetomidine is a relatively new, highly selective central alpha2 agonist. Its sedative, pro-anaesthetic and pro-analgesic effects at 0.5-2 microg/kg given intravenously stem mainly from its ability to blunt the central sympathetic response by as yet unknown mechanism(s) of action. It also minimises opioid-induced muscle rigidity, lessens postoperative shivering, causes minimal respiratory depression, and has haemodynamic stabilising effects.

Perioperative care of children with nerve agent intoxication.

Nerve agents (NA) present a major threat to civilian populations. When a ballistic system is used for spreading poison, multiple trauma, as well as toxic trauma could be caused. Children are more susceptible, due to their smaller physiological reserve. Urgent surgical intervention for combined intoxication in the multiple-traumatized child could be a tremendous task in view of the background of physiological instability. Nerve agents affect the autonomic, as well as the central nervous system, leading occasionally to unexpected interactions with agents normally used for resuscitation. This can cause additional instability, and possibly systemic collapse. This review presents and emphasizes points concerning treatment of a child who suffers from combined multiple and toxic traumas. The review is based on scant knowledge of a database of similar cases of pesticide organophosphate poisoning in children since these compounds are alike. We also extrapolated data from reports concerning episodic civilian exposure to NA.

Liver glutathione level influences myocardial reperfusion injury following liver ischemia-reperfusion.

BACKGROUND: N-acetyl-L-cysteine (NAC) both replenishes reduced glutathione (GSH) and mitigates reperfusion injury. We hypothesized that liver content of GSH could affect remote myocardial reperfusion injury following liver ischemia-reperfusion. MATERIAL AND METHODS: Following stabilization (30 min), isolated rat livers (6/group) were perfused with Krebs-Henseleit solution (two control groups) or made globally ischemic (two ischemia groups) for 120 min. Paired livers + paced hearts (Langendorff preparation) were then reperfused for 15 min after which the hearts were recirculated alone for 50 min. NAC was added to Krebs (2 mM) that perfused livers during stabilization and reperfusion phases in one control and one ischemia group. RESULTS: GSH levels in the two control liver groups were identical (30.1 +/- 5.7 [SD] nmol/mg protein), and similar to that of the ischemia + NAC livers (28.6 +/- 2.8) but 2-fold that of the ischemia + 0 livers (15.8 +/- 2.4 nmol/mg protein, p<0.05). While hearts paired with control livers maintained unchanged their myocardial velocity of contraction, the contraction in the ischemia + NAC-paired hearts reduced, but was better than in the ischemia + 0-paired hearts (71 +/- 8% vs. 41 +/- 6% off baseline, p<0.05). Coronary flow also decreased dissimilarly in the two ischemia-associated groups of heart: 72 +/- 9% (ischemia + NAC) vs. 46 +/- 7% (ischemia + 0, p<0.05). Xanthine oxidase in the ischemia + 0 livers was 7.5-folds higher than in the ischemia-treated livers. CONCLUSIONS: NAC treatment of ischemia-reperfused livers, associated with GSH replenishment, prevents remote myocardial reperfusion injury. The role of NAC and GSH in reducing liver-associated oxidative burst propagation is discussed.

External pacing does not potentiate allopurinol protection of the heart from liver ischemia-reperfusion -- a study in an isolated perfused liver-heart rat model.

BACKGROUND: We recently demonstrated that isolated paced hearts perfused with modified Krebs-Henseleit solution containing high dose allopurinol (1 mM) were protected from liver ischemia-reperfusion (IR)-induced reperfusion injury. The objective was to study the effects of low dose allopurinol together with external pacing in attenuating myocardial reperfusion dysfunction following liver IR in the same double organ model. MATERIAL AND METHODS: Isolated rat livers were perfused with modified Krebs-Henseleit solution (groups 1 and 2, n=8/all groups) or underwent global ischemia (groups 3-6) for 120 minutes. Following a 15-minute conjoint reperfusion of earlier separately isolated liver+heart, the hearts were recirculated alone for additional 45 minutes. The organs of three-group donating animals (groups 2, 4, and 6) were treated with allopurinol 18 hours and 1 hour before the experiment (50 mg x kg(-1) intraperitoneally) and it was also added during perfusion (0.1 mM in Krebs). The hearts in groups 5 and 6 were paced (300 x min(-1)). RESULTS: The hearts perfused with IR Krebs (group 3) experienced decreased myocardial left ventricular-developed pressure (LVP), heart rate (in the unpaced hearts) and later coronary flow (by 68%, 21% and 32%, respectively); LVP and coronary flow also decreased correspondingly in the IR-paced hearts (group 4). Xanthine oxidase (XO) was high in groups 3 and 4 compared to group 1. IR allopurinol-treated hearts, both unpaced and paced (groups 5 and 6) had normal, similar myocardial performance, while their circulating XO was as low as in group 2 (allopurinol-treated controls). CONCLUSIONS: External pacing in the double organ, isolated-perfused liver-heart did not ameliorate XO-mediated dysfunction compared to low dose allopurinol. The unexpected delayed coronary insufficiency in myocardial reperfusion injury is discussed.

Hemodynamic effects of tracheal administration of vasopressin in dogs.

BACKGROUND: Intravenous administration of vasopressin during cardiopulmonary resuscitation (CPR) has been shown to be more effective than optimal doses of epinephrine. Earlier studies had been performed on a porcine model, but pigs produce lysine vasopressin hormone, while humans and dogs do not. This study was designed to compare the effects of tracheal vasopressin with those of NaCl 0.9% (placebo) on haemodynamic variables in a dog model. METHODS: Five dogs were allocated to receive either vasopressin 1.2 U/kg or placebo (10 ml of NaCl 0.9%) via the tracheal route after being anesthetized and ventilated. Haemodynamic variables were determined and arterial blood gases were measured. RESULTS: All animals of the vasopressin group demonstrated a significant increase of the systolic (from 135+/-7 to 165+/-6 mmHg, P<0.05), diastolic (from 85+/-10 to 110+/-10 mmHg, P<0.05) and mean blood pressure (from 98.5+/-3 to 142.2+/-5, P<0.05). Blood pressure rose rapidly and lasted for more than an hour (plateau effect). Heart rate decreased significantly following vasopressin (from 54+/-9 to 40+/-5 beats per min, P<0.05) but not in the placebo group. These changes were not demonstrated with placebo injection. CONCLUSION: Tracheal administration of vasopressin was followed by significantly higher diastolic, systolic and mean blood pressures in the vasopressin group compared with the placebo group. Blood gases remained unchanged in both groups. Vasopressin administered via the trachea may be an acceptable alternative for vasopressor administration during CPR, when intravenous access is delayed or not available, however, further investigation is necessary.

Wrist actigraphy in anesthesia.

STUDY OBJECTIVES: To examine the use of wrist actigraphy during and following anesthesia or monitored sedation and its ability to objectively assess sleep-related events. DESIGN: Uncontrolled study. SETTING: 1100-bed tertiary care municipal, university-affiliated medical center. PATIENTS AND INTERVENTIONS: 18 patients who underwent minor to medium lower-body surgical procedures with spinal or epidural anesthesia with sedation by propofol, midazolam, or isoflurane-based general anesthesia. MEASUREMENTS AND MAIN RESULTS: Wrist actigraphy was measured and evaluated. The actigraphic recordings accurately indicated the presence and time of occurrence of all relevant perioperative events including those related to anesthesia. Actigraphic data were more precise than equivalent attending anesthesiologist's subjective observations. The anesthesiologist detected changes in the patient's activity with a delay of minutes after they had been picked up by the actigraph. The integrated areas of recorded phases of midazolam-induced sedation and the occurrence and reversal of paradoxical reactions were distinctly discernible as such, unlike the less specifically defined description of the anesthesiologist. CONCLUSIONS: Real time actigraphic monitoring can provide clear-cut and objective indications of changes in the depth of anesthesia or sedation and its associated events during surgery and recovery.

Selective attenuation of acute lung ventilatory injury by methylene blue after liver ischemia-reperfusion: a drug response study in an isolated perfused double organ model.

BACKGROUND: Liver transplantation-related ischemia-reperfusion (IR) is associated with the generation of stress oxidants that can spread damage remotely. Methylene blue (MB) had been shown to reduce lung neutrophils sequestration after in vivo intestinal IR and to have a dose-dependent potential for abrogating oxidant-induced ex vivo aortal ring reperfusion injury after liver IR. We now investigated MB's dose-dependent capabilities in preventing acute lung injury after the same liver IR. METHODS: Wistar rat livers (eight replicates/group) were perfused (control) with modified Krebs-Henseleit solution or put globally in no flow (IR) conditions for 2 hr. Separately prepared lungs were then paired with livers and "reperfused" (15 min) together. The livers were then removed, and the lungs were left to recirculate alone with the accumulated Krebs for 45 min. Three additional control and three IR groups were reperfused with Krebs containing 20, 40, or 60 mg/kg MB at concentrations of 42, 86, or 128 microM. RESULTS: All IR livers had hepatocellular and biochemical abnormalities compared with normal functions in the controls. Liver IR was associated with a 50%-75% increase in lung ventilation and perfusion pressures, vascular resistance and decreased compliance, and abnormal bronchoalveolar lavage (BAL) volume and content. Adding 42 and 86 microM MB selectively maintained normal the vascular parameters, intra-experimental lung weight gain, BAL indices, and wet-to-dry ratios. MB128 microM but not 42 or 86 microM best prevented IR-induced deterioration in lung ventilatory pressure and compliance. CONCLUSIONS: MB selectively affords maintenance of normal lung ventilatory versus vascular measures after liver ischemia-reperfusion. Its proposed differential mechanism of action is discussed.

Acute respiratory distress syndrome in children with malignancy--can we predict outcome?

PURPOSE: The purpose of this study was to delineate early respiratory predictors of mortality in children with hemato-oncology malignancy who developed acute respiratory distress syndrome (ARDS). MATERIALS AND METHODS: We conducted a retrospective chart review of children with malignant and ARDS who needed mechanical ventilation and were admitted to a pediatric intensive care unit from January 1987 to January 1997. RESULTS: Seventeen children with ARDS and malignancy aged 10.5 +/- 5.1 years were identified. Six of the 17 children (35.3%) survived. Sepsis syndrome was present in 70.6% of all the children. Peak inspiratory pressure, positive end-expiratory pressure (PEEP), and ventilation index values could distinguish outcome by day 3. A significant relationship between respiratory data and outcome related to efficiency of oxygenation, as determined by PaO(2)/FIO(2) and P(A-a)O(2), was present from day 8 after onset of mechanical ventilation. CONCLUSIONS: Peak inspiratory pressure, PEEP, and ventilation index values could distinguish survivors from nonsurvivors by day 3. This may assist in early application of supportive nonconventional therapies in children with malignancy and ARDS.