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Adequate Ventilation (adequate + ventilation)
Selected AbstractsResidential air exchange rates in three major US metropolitan areas: results from the Relationship Among Indoor, Outdoor, and Personal Air Study 1999,2001INDOOR AIR, Issue 1 2010N. Yamamoto Abstract, We report approximately 500 indoor,outdoor air exchange rate (AER) calculations based on measurements conducted in residences in three US metropolitan areas in 1999,2001: Elizabeth, New Jersey; Houston, Texas; and Los Angeles County, California. Overall, a median AER across these urban areas and seasons was 0.71 air changes per hour (ACH, or per hour; n = 509) while median AERs measured in California (n = 182), New Jersey (n = 163), and Texas (n = 164) were 0.87, 0.88, and 0.47 ACH, respectively. In Texas, the measured AERs were lower in the summer cooling season (median = 0.37 ACH) than in the winter heating season (median = 0.63 ACH), likely because of the reported use of room air conditioners as Houston is typically hot and humid during the summer. The measured AERs in California were higher in summer (median = 1.13 ACH) than in winter (median = 0.61 ACH). Because the summer cooling season in Los Angeles County is less humid than in New Jersey or Texas, natural ventilation through open windows and screened doors likely increased measured AER in California study homes. In New Jersey, AER were similar across heating and cooling seasons, although the median AER was relatively lower during the spring. Practical Implications Adequate ventilation or air exchange rate (AER) for an indoor environment is important for human health and comfort, and relevant to building design and energy conservation and efficiency considerations. However, residential AER data, especially measured by more accurate non-toxic tracer gas methodologies, are at present quite limited worldwide, and are insufficient to represent the variations across regions and seasons within and between homes, including apartments and condominiums in more densely populated urban areas. The present paper presents quantitative and qualitative data to characterize residential AERs in three US urban areas with different climate attributes. [source] Insertion and use of the LMA SupremeÔ in the prone position,ANAESTHESIA, Issue 2 2010A. M. López Summary We investigated whether insertion of an LMA SupremeÔ and its use for maintenance of anaesthesia is feasible in the prone position. Forty adult patients positioned themselves prone and were given propofol until the Bispectral Index was < 50. A size-4 LMA Supreme was inserted by experienced anaesthetists. Ease of insertion, ease of ventilation, efficacy of seal, ease of gastric tube insertion, blood staining, postoperative sore throat, and other complications were recorded. Insertion was successful at the first and second attempt in 37 (92.5%) and 3 (7.5%) patients, respectively. The mean (SD) insertion time was 21 (15) s. Oropharyngeal leak pressure was greater in females than males (29 (4) vs 25 (4) cmH2O, respectively, p = 0.01). Adequate ventilation was achieved in all patients. Gastric tube placement was successful in all patients. The frequency of blood staining and sore throat was 7.5% each. No other complications were noted. We conclude that use of the LMA Supreme in the prone position by experienced users is feasible. [source] Grave acidosis after severe anaphylactic bronchospasm: friend or foe?ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2007M. Pytte In a 20-year-old woman with known asthma, anaphylactic bronchospasm induced a grave combined respiratory and metabolic acidosis (pHa 6.66) with marked hypoxaemia (SaO2 45%). The beneficial effects of the rightward shift of the oxyhaemoglobin dissociation curve on tissue O2 unloading at such pH was more than offset by the negative effect on SaO2 at the reduced PaO2 (7.0 kPa) found in this patient. This case illustrates the detrimental effect of grave acidosis on arterial blood oxygen content at subnormal PaO2 values, the beneficial effect of a supranormal PaO2 on the SaO2 in such patients, and the rapid remission rate of life-threatening acidosis and blood lactate after adequate ventilation and tissue oxygenation were secured. The initial treatment of the patient and clinically relevant considerations are discussed. [source] Brain edema in liver failure: Basic physiologic principles and managementLIVER TRANSPLANTATION, Issue 11 2002Fin Stolze Larsen MD In patients with severe liver failure, brain edema is a frequent and serious complication that may result in high intracranial pressure and brain damage. This short article focuses on basic physiologic principles that determine water flux across the blood-brain barrier. Using the Starling equation, it is evident that both the osmotic and hydrostatic pressure gradients are imbalanced across the blood-brain barrier in patients with acute liver failure. This combination will tend to favor cerebral capillary water influx to the brain. In contrast, the disequilibration of the Starling forces seems to be less pronounced in patients with cirrhosis because the regulation of cerebral blood flow is preserved and the arterial ammonia concentration is lower compared with that of patients with acute liver failure. Treatments that are known to reverse high intracranial pressure tend to decrease the osmotic pressure gradients across the blood-brain barrier. Recent studies indicate that interventions that restrict cerebral blood flow, such as hyperventilation, hypothermia, and indomethacin, are also efficient in preventing edema and high intracranial pressure, probably by decreasing the transcapillary hydrostatic pressure gradient. In our opinion, it is important to recall that rational fluid therapy, adequate ventilation, and temperature control are of direct importance to controlling cerebral capillary water flux in patients with acute liver failure. These simple interventions should be secured before more advanced experimental technologies are instituted to treat these patients. [source] Raynaud's phenomenon in a child presenting as oxygen desaturation during transfusion with cold bloodPEDIATRIC ANESTHESIA, Issue 12 2008XIAOPENG ZHANG MD Summary We report a case of Raynaud's phenomenon (RP) triggered by transfusion of cold blood to a pediatric burn patient under general anesthesia. The child was febrile so a decision was made to not use a blood warmer. When the blood was rapidly administered the child suddenly developed ,desaturation'. The child was placed on 100% oxygen, adequate ventilation assured, and the color of his oral mucosa assessed as ,pink'. Placement of the oximeter on the opposite hand revealed 100% saturation. To our knowledge, this is the first case of apparent RP reported in a pediatric patient triggered by transfusion of cold blood. [source] Life threatening unilateral pulmonary overinflation might be more successfully treated by contralateral selective intubation than by emergency pneumonectomyPEDIATRIC ANESTHESIA, Issue 5 2003Josef Holzki MD Summary During a period of 3 years, three infants were admitted to our hospital for unilateral emergency pneumonectomy due to life threatening overinflation of one lung, preventing adequate ventilation of the unaffected contralateral side. All three patients were able to be stabilized by unilateral selective bronchial intubation of the unaffected lung after bronchoscopy, ruling out a flap valve mechanism. No emergency pneumonectomies were required. In one patient, lung function of the overinflated side (three lobes) recovered fully and, in the two remaining patients, one lobe of the overinflated side recovered. The overinflated lobes were removed later by elective surgery, thus not exposing the children to a potentially dangerous emergency operation. These results are in contrast with reports in the literature. Emergency pneumonectomy in neonates and infants due to overinflation of one lung may be avoided by selective unilateral intubation of the main stem bronchus of the compressed lung. [source] Suspension Laryngoscopy for Endotracheal Stenting,THE LARYNGOSCOPE, Issue 1 2003Hans Edmund Eckel MD Abstract Objectives/Hypothesis Airway stents have recently been used to establish and maintain patent airways in patients with malignant central airway obstruction, but insertion modalities remain controversial to date. The study seeks to determine the role of suspension laryngoscopy in interdisciplinary airway stenting. Study Design Retrospective, single-institution analysis of a case series treated by a multidisciplinary airway team. Methods Ninety-three consecutive patients with malignant obstruction of the trachea and/or tracheobronchial bifurcation underwent endotracheal stenting through a suspension laryngoscopy approach for the relief of impending respiratory distress. Feasibility, mortality, survival, and complications were analyzed as main outcome measures. Results Stenting through a suspension laryngoscopy approach was feasible 91 of 93 patients (97.8%). Fifteen patients needed repeated stenting, and in all, 121 stents were implanted during the observation period. This approach allowed for the repeated insertion of rigid bronchoscopes of graded sizes to establish an airway and for precise stent positioning. Optical instruments and stent introducer systems could easily be used while adequate ventilation was continuously maintained. Silicone stents of maximal size were inserted without injury of the vocal cords during intubation. Median survival for all patients was 8 months. No intraoperative airway complications were observed, and no patient died secondary to stenting. Conclusions Suspension laryngoscopy and jet ventilation provide an ideal setting for the precise placement of tracheal and bifurcation airway stents. Laryngologists should actively participate in interdisciplinary airway stenting programs. [source] A comparison of the intubating laryngeal mask airway and the Bonfils intubation fibrescope in patients with predicted difficult airways,ANAESTHESIA, Issue 7 2004B. Bein Summary Tracheal intubation with the intubating laryngeal mask airway or the Bonfils intubation fibrescope was performed in 80 patients with predicted difficult airways. Mallampati score, thyromental distance, mouth opening and mobility of the atlanto-occipital joint were used to predict difficult airways. The overall success rate, time to the first adequate lung ventilation and time taken for the successful placement of the tracheal tube were recorded, as well as a subjective assessment of the handling of the device and the incidence of postoperative sore throat and hoarseness. The median [range] time to the first adequate ventilation was significantly shorter with the intubating laryngeal mask airway than with the Bonfils intubation fibrescope (28 [6,85] s vs. 40 [23,77] s, p < 0.005). Tracheal intubation was significantly slower with the intubating laryngeal mask airway than with the Bonfils intubation fibrescope (76 [45,155] s vs. 40 [23,77] s, p < 0.0001. Patients in the Bonfils group suffered less sore throat and hoarseness than those in the other group. [source] | ||||||||||