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.

Mesenteric artery clamping/unclamping-induced acute lung injury is attenuated by N-methyl-D-aspartate antagonist dextromethorphan.

Lung N-methyl-D-aspartate receptors (NMDAR) may cause excitotoxic pulmonary edema if activated. Acute lung injury may be mediated by oxidative stress, frequently generated by local or remote ischemia and reperfusion (IR). This experimental study assessed the effects of intravenous dextromethorphan, an NMDAR antagonist, on reperfusion lung injury following superior mesenteric artery (SMA) clamping/unclamping. SMA of 48 (12 per group) anesthetized adult male Wistar rats was clamped for 90 min (IR); 48 additional rats underwent a sham laparotomy (control). The experimental timeframe was identical in all groups. Ten minutes before unclamping, three dextromethorphan doses were administered intravenously in three IR and three control groups, followed by 3 h of respiratory and hemodynamic assessment and postexperimental assessment of survival. Intravenous 10 and 20 mg/kg dextromethorphan attenuated an 85% increase in peak ventilatory pressure, a 45% reduction in PO(2)/FiO(2), 4-12-fold increase in bronchoalveolar lavage-retrieved volume, and polymorphonuclear leukocytes/bronchoalveolar cells ratio, all associated with SMA unclamping in the IR-nontreated and the IR-40 mg/kg dextromethorphan-treated rats. Lung tissue polymorphonuclear leukocyte count, total xanthine oxidase activity, reduced glutathione, and wet-to-dry weight ratio were all within normal ranges in the two lower-dose-treated groups. These effective regimens were also associated with longer postexperimental animal survival. Dextromethorphan was not associated with changes in three control groups. Thus, Intravenous dextromethorphan mitigates lung reperfusion injury following SMA clamping/unclamping in a dose-dependent manner. This is a novel potential use of dextromethorphan in vivo.

Predictors of adverse outcome from candidal infection in a tertiary care hospital.

OBJECTIVES: To retrospectively delineate predictors of adverse outcome by looking at the demographic features, therapy and outcome of systemic candida infection in a large tertiary care university-affiliated medical center. METHODS: We reviewed the clinical data on 186 inpatients with candidemia over a 6-year period. The major reason for their hospital admission was an underlying malignancy or an infection other than candidemia. RESULTS: Candida albicans, tropicalis, parapsilosis, glabrata and krusei caused 54, 22, 13, 8 and 3% of the candidemia episodes, respectively. The overall mortality was 42% and it was highest in patients suffering from candidemia of the glabrata species (73%). Forty-eight (63%) of the 76 patients who received no anti-fungal treatment died compared to 38 (34%) of 110 patients who were treated (P < 0.05). Predictors of adverse outcome were intensive care unit stay, renal failure, thrombocytopenia and the need for mechanical ventilation or inotropic support. CONCLUSIONS: We identified four predictors of mortality from candidemia infection. Their validity should be further assessed and the specific candida strains and their susceptibility need to be methodically identified. Our data support immediate initiation of therapy at first identification of infection.

Cysteine-induced hypoglycemic brain damage: an alternative mechanism to excitotoxicity.

Central neural damage caused by L-cysteine (L-Cys) was first reported more than 30 years ago. Nevertheless, the exact mechanisms of L-Cys-mediated neurotoxicity are still unclear. Preliminary study in mice demonstrated that, following L-Cys injection, animals developed tachypnea, tremor, convulsions, and death in conjunction with documented hypoglycemia. The aim of the present study was to further investigate the mechanism of L-Cys-mediated hypoglycemic effect and neural damage. Neonatal ICR mice (n=6) were injected with L-Cys (0.5-1.5 mg/g body weight [BW]), and their blood glucose and insulin levels were determined up to 90 min following the injection. Experiments were repeated in chemically (streptozotocin [STZ]) pancreatectomized animals. Brain histology was assessed. Mice injected with L-Cys exhibited dose-dependent neurotoxicity and higher mortality as compared with controls. L-Cys (1.2-1.5 mg/g BW) caused severe hypoglycemia (glucose<42 mg/dl) ( P<0.001). In STZ-treated (diabetic) animals, L-Cys (1.5 mg/g BW) increased plasma insulin levels 2.3-fold and decreased serum glucose levels by 50% ( P<0.01). Brain histology revealed destruction of as much as 51% of hippocampal neurons in the L-Cys-treated mice but not in the glucose-resuscitated animals. These findings suggest that L-Cys injection can cause pronounced hypoglycemia and central neural damage which is glucose reversible. Since L-Cys is chemically different from the other excitatory amino acids (glutamate and aspartate), L-Cys-mediated neurotoxicity may be connected to its hypoglycemic effect.

Gray-white matter discrimination--a possible marker for brain damage in heat stroke?

INTRODUCTION/OBJECTIVE: Heat stroke (HS) is a common medical emergency which carries high morbidity and morality. This study was designed to describe the pattern of central nervous system (CNS) changes as detected by brain CT scan in a case series of six patients suffering from classical and exertional HS. METHODS AND PATIENTS: All the patients were admitted in critical condition during the heat wave in the summer of 1999 in Israel. Each was in deep coma with a measured core temperature of over 40 degrees C upon admission to the emergency department. RESULTS: Aggressive cooling measures decreased the core temperature to <38 degrees C within 30 min following admission. Two patients (33.3%) died. One of the survivors remained in a vegetative state. Brain CT studies carried out within 4 days of admission in all the patients revealed severe loss of gray-white matter discrimination (GWMD) without signs of acute bleed or significant focal lesion, findings that persisted in repeated brain CTs in one patient who remained in a vegetative state. DISCUSSION AND CONCLUSIONS: Loss of GWMD may represent an early and sensitive indication of severe brain damage in patients with severe HS. Further studies in larger groups of patients are warranted in order to determine whether the appearance of GWMD in brain CTs of patients with HS has prognostic value.

Invasive group A streptococcal infections in a large tertiary center: epidemiology, characteristics and outcome.

BACKGROUND: Invasive group A streptococcal (GAS) infections are increasing alarmingly worldwide. PATIENTS AND METHODS: To determine the clinical and epidemiologic characteristics of invasive GAS in a large tertiary medical center, we retrospectively surveyed microbiology and medical records of patients with invasive GAS infections (isolation of Group A Streptococcus from a normally sterile site) treated in our hospital from January 1995 to December 1997. RESULTS: 70 patients with a median age of 48 years (range 2 months-88 years) were identified. Of the 70 identified, 53 (76%) were adults (age > or = 19 years). The most common co-morbid diseases for invasive GAS in adults were diabetes mellitus, congestive heart failure (CHF), malignancy and immunosuppression. A probable port of entry was identified in 31 (44%) of the cases. In children, varicella lesions were the major port of entry. Overall mortality rate was 17%: The difference in mortality between pediatric and adult cases was significant (0/17 vs 12/53, respectively; p = 0.03). Toxic shock syndrome (TSS) and necrotizing fasciitis were identified in 8.6% and 5.7% of the cases, respectively, with mortalities of 83.3% and 25%. Hyponatremia and hypocalcemia were more frequently observed among the severely ill. CONCLUSION: Invasive GAS infections tend to have an unexpected course and a broad clinical spectrum, ranging from local skin or pharyngeal involvement to deeply invasive fasciitis with TSS and high mortality. The elderly and those with underLying medical conditions are at utmost rsk for invasive GAS. Clear-cut guidelines for early therapeutic strategy, i.e. antibiotic administration and preemptive hospital admission are needed for community-based physicians.

Religious sensitivity pitted against the need to know: autopsy of Jewish children in Israel.

BACKGROUND: The aim of the study was to compare autopsy findings with antemortem findings in children who died in a pediatric intensive care unit. MATERIAL/METHODS: Consecutive series of patients who died in the pediatric intensive care unit during 2-year period were used. The study was conducted as a retrospective chart review at community, regional-referral, university-affiliated tertiary medical center of 1200 bed in Israel. RESULTS: Permission was given to perform autopsies on only 10 children (23.8%, mean age 85.7 months) out of the 42 who died during the study period. The mean length of stay in the pediatric intensive care unit prior to death was 13.3 days. Cardiac or hemato-oncologic diseases comprised the major pre-admission diagnoses. The autopsy revealed a major finding that, if known before death, would have altered clinical management in 50% of the patients: pneumonia, pneumonitis as well as intestinal perforation or necrosis. No correlation was found between patient length of stay in the intensive care unit and the autopsy disclosed information. CONCLUSIONS: Our findings support the importance of autopsy assessment in the pediatric intensive care setup. We believe that postmortem examination is also essential for improving the quality of pediatric patient care.

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.

Circulating leptin levels after cardiopulmonary bypass in children.

OBJECTIVE: To characterize the dynamics of circulating leptin in children after cardiac surgery with cardiopulmonary bypass (CPB), which is known to induce a systemic inflammatory response. DESIGN: Investigative study. SETTING: University-affiliated tertiary care hospital. PARTICIPANTS: Eight children (age range, 3 months to 13 years) undergoing CPB to correct congenital heart disease. INTERVENTIONS: The time courses of leptin and cortisol levels were determined. Serial blood samples were collected from the arterial catheter or from the CPB circuit preoperatively; on termination of CPB; and at 2, 4, 8, 12, 18, and 24 hours postoperatively. Plasma was recovered immediately, divided into aliquots, and frozen at -70 degrees C until use. Leptin was measured by a human leptin radioimmunoassay kit. MEASUREMENTS AND MAIN RESULTS: Leptin levels during CPB decreased to 50% of pre-CPB levels (p < 0.01). After termination of CPB, levels increased gradually and peaked at 12 hours postoperatively (10 P.M. to 1 A.M.). Cortisol levels were inversely correlated to leptin levels (p = 0.016). CONCLUSION: CPB is associated with acute changes in circulating leptin levels. These changes parallel those in cortisol, showing an inverse relationship between leptin and cortisol, suggesting a relationship between the neurobiology of these systems that could be important for the neuroendocrine response to CPB. A prognostic role of leptin and its relationship to cortisol after CPB warrant further study.

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.

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.

Snakebite poisoning in children--a call for unified clinical guidelines.

In Israel, there are no uniform guidelines for the treatment policy of children snake-bitten by the Vipera palaestinae, the most abundant venomous snake in the country. We conducted a retrospective study aiming to compare treatment policies in two different medical centers. We found significant differences regarding admission and steroid administration criteria. Although the differences between the centers regarding anti-venom administration did not reach statistical significance, there were substantial differences. Neither of the centers had a well-established policy for the treatment of snake envenomation in children. In the era of cost containment, a policy of routine admission of children to the PICU service following V. palaestinae envenomation is unjustified, especially since the introduction of a specific monovalent anti-venom into the therapeutic armamentarium.

[The benefit of combining spinal morphine and intravenous buprenorphine for perioperative pain].

Concurrent administration of opioids with different affinity produces synergistic antinociceptive effect in rats. We tested the perioperative antinociceptive effects of the simultaneous double blind administration of morphine, a pure agonist and buprenorphine, a partial agonist, in 30 patients undergoing hysterectomy under general anesthesia. Pre- and post-operatively regimens consisted of random patient assignment to intrathecal 0.3 mg morphine plus intravenous saline (group 1), intravenous 0.09 mg buprenorphine plus intrathecal saline (group 2) or intrathecal morphine 0.3 mg plus intravenous buprenorphine 0.09 mg (group 3). Postoperative pain relief for group 3 consisted of supplementation of intravenous buprenorphine plus intrathecal saline. The immediate postoperative pain, sedation and anxiety levels (by numerical or categorical scores) were similar among all groups. The 12-hour pain and sedation scores were significantly (P < 0.05) lower in group 3 than in the other two groups. Buprenorphine-induced analgesia in group 3 lasted significantly (P < 0.05) longer than in group 2. Side effects in groups 2 and 3 were by 44% and 42% fewer than in group 1, respectively, with no withdrawal symptoms. Thus, concomitant administration of intrathecal morphine and low dose intravenous buprenorphine produces better and longer pain relief than intravenous buprenorphine alone in women after hysterectomy.

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.

Role of the molecular adsorbent recycling system (MARS) in the treatment of patients with acute exacerbation of chronic liver failure.

OBJECTIVE: To test the efficacy of the molecular adsorbent recycling system (MARS) in patients with acute exacerbation of chronic liver disease. DESIGN: A prospective case analysis. SETTING: A university-affiliated tertiary medical center. PATIENTS AND METHODS: We applied MARS to treat a consecutive series of eight patients with acute exacerbation of chronic liver disease. RESULTS: The overall survival rate was 62.5%. All patients demonstrated improvement with regard to their degree of encephalopathy. In three patients, intracranial pressure and jugular bulb oxygen saturation decreased and cerebral perfusion pressure increased after treatment institution. Patients' hyperdynamic state was attenuated, as demonstrated by elevation of systemic vascular resistance, mean arterial pressure, and parallel reduction in cardiac index. A prompt reduction in serum ammonia, bilirubin, and lactate levels was observed. There were no complications during the treatment period. CONCLUSIONS: Applying MARS treatments to patients with acute exacerbation of chronic liver disease can detoxify blood, improve cerebral circulation, and reduce brain edema, as reflected by the reduction in intracranial pressure and jugular bulb oxygen saturation values in our patients. A partial reversal of the characteristic hyperdynamic circulation was also achieved. Despite our encouraging results, further testing is needed to determine the reliability of the system.