Effect of electrically heated humidifier on intraoperative core body temperature decrease in elderly patients: a prospective observational study

BACKGROUND: Core body temperature (TC) can decrease during general anesthesia. Particularly in elderly patients, more aggressive strategies to prevent intraoperative hypothermia may be required. Here, we investigated the effect of a heated humidifier on intraoperative TC decrease in the elderly. METHODS: Twenty-four elderly patients were randomly assigned into two groups: those who used a heated humidifier (group H) and those who used a conventional ventilator circuit with a heat moisture exchanger (group C). TC was measured continuously at the esophagus at several time-points during surgery. RESULTS: In group C, TC significantly decreased 90 minutes after skin incision (P < 0.001), while significant differences were not noted in group H during surgery. Comparing the two groups, TC decreased more in group C than in group H at 60, 90, 120, and 150 minutes after skin incision (group C vs. group H: -0.6℃ vs. -0.3℃, P = 0.025; -0.7℃ vs. -0.4℃, P = 0.012; -0.9℃ vs. -0.4℃, P = 0.006; and -1.0℃ vs. -0.5℃, P = 0.013, respectively). There were no significant differences between the two groups for any other parameters. CONCLUSIONS: A heated humidifier is more effective in preventing intraoperative TC decrease in elderly patients than a heat moisture exchanger. However, further studies with a larger population are required to substantiate its clinical use.

Influences of Tidal Volume on Contents of PMN,TNF-?,IL-6 and IL-8 in Bronchoalveolar Lavage Fluid After Closed Circuit Anesthesia in Infants / 医学研究杂志

Objective The author seeked the suitable tidal volume in order to decrease mechanical ventilation-induced lung injury during closed circuit anesthesia in infants.Methodes 50 infants who practiced selective orthopedics operation randomly divided into traditional mode(12~15ml/kg,groupT,n=25)and low tidal volumes(7~8ml/kg,groupL,n=25).The bronchoalveolar lavage fluid of intants were collected immediately after tracheal intubation(T1)and before tracheal extubation,respectively.Interleukin-6 and interleukin-8 in the bronchoalveolar lavage fluid were determined by enhancement solid-phase enzyme immunoassay action(EASIA),TNF-? in the bronchoalveolar lavage fluid were determined by euzymelinked immunosorbent assay(EIA).The numbers of polymorphonuclear neutrophils in the bronchoalveolar lavage fluid of intants were examined.The infants' SpO2,arterial blood pressure and PetCO2 were monitored continuously.Arterial blood gas was analysised.The time of analepsia and complications of lung were observed after operation.Results PaCO2、PetCO2 in groupL were higher than that in groupT,pH in groupL lower than that in groupT at 30 min,60 min,120 min after mechanical ventilation and before extubation,respectively.The contents of PMN,TNF-?,IL-6 and IL-8 in BALF collected at T2 more than that at T1 in groupT.The contents of PMN,TNF-?,IL-6 and IL-8 in BALF in groupL less than that in groupT at T2(P

Effect of Ambroxol on Contents of PMN,TNF-?,IL-6 and IL-8 in Bronchoalveolar Lavage Fluid after Closed Circuit Anesthesia in Infants / 医学研究杂志

Objective To investigate the effect of ambroxol administered before surgery on contents of PMN,TNF-?,IL-6 and IL-8 in bronchoalveolar lavage fluid after closed circuit anesthesia in infants.Methods 40 infants who practiced selective orthopedics or abdominal operations were randomly divided into ambroxol group (group A) and control group (group B). Two days before operation,infants in group A and group B were administed ambroxol 0.3 mg/kg or 0.9 normal saline 10 ml through intravenous injection three times per day,respectively .The last single dose was administered before anesthesia induction.The bronchoalveolar lavage fluid of intants were collected immediately after tracheal intubation(T1) and before tracheal extubation(T2),respectively.Interleukin-6 and interleukin-8 in the bronchoalveolar lavage fluid were determined by enhancement solid-phase enzyme immunoassay action(EASIA),and TNF-? in the bronchoalveolar lavage fluid by euzymelinked immunosorbent assay (EIA).The numbers of polymorphonuclear neutrophils in the bronchoalveolar lavage fluid were examined. The contents of PMN,TNF-?,IL-6 and IL-8 in two groups were compared .The time of analepsia and complications of respiratory tract were observed after operation.Results Compared with group A, the contents of PMN,TNF-?,IL-6 and IL-8 in BALF collected at T2 were significant higher in group B (P

Effect of Fresh Gas Flow on the Work of Breathing of Closed Circuit Anesthesia Using Semiclosed Circuit System / 대한마취과학회지

BACKGOUND: The effect of anesthetic techniques, such as closed circuit anesthesia (CCA) using semiclosed circuit system and semiclosed circuit anesthesia (SCCA), on the work of breathing has not been studied yet in detail. This study was purposed to compare the work of breathing according to anesthetic technique (CCA, SCCA). METHODS: Thirty patients were assigned to receive either SCCA group or CCA group (n = 15). Anesthesia was induced with propofol 2 mg/kg with 2% lidocaine 1 ml. Two percents isoflurane with O2 and N2O 2 L/min were given for 10 min to patients initially to wash in functional residual capacity and the breathing circuits. In SCCA group, anesthesia was maintained with 2% isoflurane in O2 2 L/min and N2O 2 L/min throughout the surgery. In CCA group, O2 was reduced to 200 ml/min and N2O to 100 ml/min with isoflurane vaporizer setting adjusted to 4% for anesthesia maintenance. When the operation was ended, the vaporizer setting of isoflurane deceased to zero and then O2 was increased to 4 L/min for the arousal of the patient. We measured the inspiratory/expiratory concentration of isoflurane, end-tidal CO2, the hemodynamic parameters, the change of airway pressure, the work of breathing, and compliance at anesthetic induction and emergence in both groups. RESULTS: There were no significant differences in the inspiratory/expiratory concentrations of isoflurane, the hemodynamic parameters, end-tidal CO2, airway pressure, the work of breathing and compliance between the groups. CONCLUSIONS: CCA using semiclosed circuit system does not increase the work of breathing compared to SCCA.

Comparison of Ventilations with LMA and Endotracheal Tube during Closed Circuit Anesthesia / 대한구급학회지

BACKGROUND: LMA has larger dead-space than tracheal tube, ventilation may be influenced by difference of dead space. Closed circuit mechanical ventilation has high risk of hypercarbia because of inadequate CO2 elimination or gas supply. Thus, end-tidal carbon dioxide tension (EtCO2) and arterial carbon dioxide tension (PaCO2) were compared during closed circuit mechanical ventilation with LMA or tracheal tube. METHODS: Thirty adult patients scheduled for general anesthesia were divided into 2 groups. After induction of general anesthesia, laryngeal mask airway (Group 1, n=15) or tracheal tube (Group 2, n=15) were randomly inserted and closed circuit mechanical ventilation was initiated. When steady state had been reached, PaCO2 and EtCO2 were recorded. RESULTS: The PaCO2 was 32.2+/-2.8 (Group 1), 31.5+/-2.2 (Group 2) and the EtCO2 was 33.0+/-2.9, 31.6+/-2.4 respectively and there was no statistical significance between groups. The difference of arterial and end-tidal carbon dioxide tension in each group was -0.8+/-2.6, -0.03+/-2.2 respectively and there was no statistical significance between groups. CONCLUSIONS: The results indicate that in patients who are mechanically ventilated via the closed circuit system, EtCO2, PaCO2, and the difference between arterial and end-tidal carbon dioxide tension were not significantly different between groups.