高频喷射通气对吸入性损伤犬呼吸气流与气体交换的影响

目的观察犬吸入性损伤时呼吸气流对气体交换的影响。方法用三维粒子动态分析仪测定犬自主呼吸时吸气和呼气流速。将实验动物通入高压蒸气5秒后随机进行五种不同条件高频喷射通气,每种通气方式通气20分钟,并根据公式Re=Vrρ/η计算出雷诺数,同时采取动脉血标本,观察Pa-CO_2、PaO_2PIP的变化。结果①自主呼吸时吸气为层流,呼气可能为层流,也可能为涡流;②高频喷射通气(HFJV)时呼气和吸气均为涡流;③高频双向喷射通气(HFTJV)与HFJV相比,呼气流速显著增加(P<0.05),PaCO_2显著降低(P<0.05),呼气流速与PaCO_2呈负相关(r=-0.9216,P<0.05),同时吸气流速也有增加的趋势。结论 HFJV可维持吸入性损伤犬正常通气,其机制可能与涡流有关。HFTJV是在HFJV基础上增加了反向喷射气流,可以增进呼吸气体速度,促进CO_2排除。     

高频部分液体通气对吸入伤犬呼吸循环功能的影响

目的　观察高频部分液体通气 (highfrequencypartialliquidventilation ,HFPLV)对吸入性损伤犬肺力学、氧合和血流动力学参数的影响。　方法　 16条犬经吸入蒸气 ,造成重度吸入性损伤模型 ,并随机分为对照组和治疗组。两组动物致伤后均行高频喷射通气 (highfrequencyjetventila tiot,HFJV) ,治疗组同时经气管导管缓慢注入氟碳液体 (3ml/kg体重 ) ,行HFPLV治疗 ,于通气后3 0、60和 90min时测定两组动物血气、肺顺应性、气道阻力及血流动力学参数。　结果　治疗组PaO2 呈进行性上升 ,在各时相点与致伤后比较差异有显著性意义 (P <0 .0 5 ) ,而对照组各时相点与致伤后比较差异无显著性意义 (P >0 .0 5 ) ;治疗组PaCO2 也逐渐增高 ,于 60、90min显著高于致伤后水平 (P <0 .0 5 )。与对照组比较 ,治疗组各时相点的PaO2 稍有升高 (P >0 .0 5 ) ,PaCO2 于 90min显著增高 (P <0 .0 5 ) ,而两组动 /静态气道阻力、肺顺应性和血流动力学参数比较 ,差异均无显著性意义 (P >0 .0 5 )。　结论　HFPLV与单纯HFJV相比 ,更有利于吸入性损伤的动脉氧合 ,对血流动力学参数无明显不利影响     

高频双向喷射通气时反喷驱动动压和组织胺犬气体交换及呼吸…

本实验观察了高频双向喷射通气（ＨＦＴＪＶ）时反喷驱动压（ＩＤＰ）对组织胺致肺损伤犬ＣＯ２排除效能及呼吸力学的影响。结果表明，静脉滴注组织胺可引起ＰａＯ２，平均动脉压，肺及呼吸系统顺应性显著降低，ＰａＣＯ２，峰值气道压，肺及呼吸系统阻力显著升高。在组织胺持续滴注时，ＨＦＴＪＶ时的ＰａＣＯ２及ＦＲＣ较ＨＦＪＶ时均显著降低（Ｐ〈０．０５），Ｖｃｏ２显著升高（Ｐ〈０．０５），而ＰａＯ２，气道压，肺及呼吸…     

高频喷射通气对重度烧伤合并吸入性损伤患者早期的呼吸支持

目的　观察高频喷射通气 (highfrequencyjetventilation ,HFJV)对重度烧伤合并吸入性损伤患者早期的治疗作用。　方法　 2 0例重度烧伤 (TBSA 79.6 %± 2 9.3% )并吸入性损伤患者 ,其中 19例行气管切开手术 ,1例经鼻插管。为防低氧血症 ,所有患者均应用HFJV ,观察通气前和通气后 11d内血气、呼吸率和脉搏等指标的变化。　结果　气管切开时间为伤后 (2 .7± 2 .4 )d ,HFJV时间为伤后(4.4 0± 2 .9)d。HFJV后 1～ 3d ,PaO2 显著高于通气前水平 (P <0 .0 1) ,随后HFJV 1周 ,PaO2 仍维持在较高水平。在整个通气期间 ,PaCO2 、呼吸率和脉搏率均无明显变化。结论　在重度烧伤合并吸入性损伤早期 ,HFJV有利于氧合作用的改善而无明显副作用 ,是一较为适用的呼吸支持方式     

蛛网膜下腔穿刺测压法观察不同通气方式对颅内压的影响

神经外科手术病人术前多有程度不同的颅内压（ICP）增高,术中影响ICP者除麻醉药物、手术等因素外,呼吸形式亦不可忽视。本研究观察了保留自主呼吸（SR）、人工控制呼吸（CMV）及高频喷射通气（HFJV）三种通气方式对ICP的     

蒸气吸入损伤犬高频喷射通气时两种不同方向气流通气效果观察

制备犬蒸气吸入损伤模型,比较高频喷射通气时两种不同方向的喷射气流对呼吸、循环的不同影响,以了解气管内高频双向喷射通气机理。根据在呼气期增加气流的方向不同而分三种模式:模式一为对照组,呼气期不增加任何气流;模式二,为呼气期增加反向气流;模式三,呼气期增加正向气流。实验结果表明,模式二通气效果优于模式一,表现为 CO_2排出明显增加(P<0.01),PaCO_2明显减少(P<0.01),其机理可能是由于死腔减少。模式三与模式一比较解剖死腔和生理死腔虽然也有所减少,但通气效果反而恶化,其原因可能与呼气末正压及功能残气增加有关。我们初步认为,对于已发生Ⅱ型呼衰的吸入性损伤,宜用高频(正反)双向喷射通气,不宜采用高频喷射通气 呼气末正压的通气方式。     

蒸气吸入损伤犬高频喷射通气时两种不同方向气流通气效…

制备犬蒸气吸入损伤模型，比较高频喷射通气时两种不同方向的喷射气流对呼吸，循环的不同影响，以了解气管内高频双向喷射通气机理。根据在呼气加气流的方向不同而分三种模式；模式一对照组，呼气期不增加任何气流；模式二、为呼气期增加反向气流；模式三，呼气期增加正向气流。     

腹腔常频和高频喷射给氧对急性呼吸窘迫综合征家犬低血氧的改善效果

目的观察经腹腔常频喷射通气(CFJV)和高频喷射通气(HFJV)给氧对急性呼吸窘迫综合征(ARDS)家犬低血氧的改善效果。方法 15只家犬常规麻醉后在温盐水肺灌洗诱发ARDS模型后,将实验动物随机均分为三组,分别为对照组(C组)、CFJV组和HFJV组,并进行各组相应处理。观察三组建模前(T0)、建模时(T1)、建模后15min(T2)、30min(T3)、60min(T4)、90min(T5)、120min(T6)时动、静脉血氧分压、电解质、HR、MAP的变化。结果与T0时比较,T1时三组PaO2、PvO2明显降低、PaCO2明显升高(P<0.05)。与C组比较,T2～T6时HFJV组、T2和T3时CFJV组PaO2明显升高(P<0.05);T2～T4时HFJV组PaCO2和T3～T6时HFJV组和CFJV组PvO2明显升高(P<0.05)。与CFJV组比较,T5、T6时HFJV组PaO2明显升高(P<0.05)。三组电解质、HR、MAP差异均无统计学意义。结论腹腔CFJV和HFJV给氧对急性肺损伤家犬低血氧均有显著改善效果。     

高频喷射通气对胸交感神经离断术患者呼吸循环的影响

目的 研究高频喷射通气对胸交感神经离断术中的患者呼吸循环的影响.方法 30例拟行择期胸交感神经离断术患者随机均分为两组,Ⅰ组行高频喷射通气,Ⅱ组行单肺通气.观察手术开始后10、20、30 min时两组患者呼吸循环的变化.结果 两组患者手术开始后10、20、30 min时MAP、HR差异无统计学意义,SpO2、PaO2均在正常范围,Ⅱ组患者手术开始后20min时PaCO2显著高于手术开始后10、30 min时(P＜0.05),但在可允许范围内.结论 胸交感神经离断术中行高频喷射通气是安全有效的选择.     

高频-常频叠加喷射通气在无痛纤维支气管镜检查治疗中的应用

目的对比研究叠加高频喷射通气(即高频‑常频叠加喷射通气)与高频喷射通气应用于无痛纤维支气管镜检查(fiberoptic bronchoscope,FOB)气道管理中的临床效果。方法择期行无痛FOB治疗的患者40例,按随机数字表法分为高频喷射通气组(H组)和高频‑常频叠加喷射通气组(S组),每组20例。患者麻醉诱导后置入喉罩,H组采用单纯高频喷射通气,S组采用高频‑常频叠加喷射通气。记录两组患者入室(T_(0)),高频‑常频叠加喷射通气或高频喷射通气15 min(T_(1))、30 min(T_(2)),恢复自主呼吸即刻(T_(3))时的心率、MAP、SpO_(2)、pH值、PaCO_(2)、PaO_(2)、血糖、皮质醇、C反应蛋白(C‑reactive protein,CRP)和IL‑6浓度;记录术中因P_(ET)CO_(2)>80 mmHg(1 mmHg=0.133 kPa)暂停手术操作的患者例数。结果两组患者均未见低氧血症发生。与T_(0)时比较:两组患者T_(2)、T_(3)时心率升高(P<0.05),T_(1)~T_(3)时SpO_(2)、PaO_(2)、IL‑6升高(P<0.05);H组T_(2)、T_(3)时MAP、血糖和皮质醇升高(P<0.05),T_(3)时CRP升高(P<0.05),T_(1)~T_(3)时pH值降低、PaCO_(2)升高;S组T_(3)时MAP、血糖和皮质醇升高(P<0.05),T_(2)时pH值降低(P<0.05)。与H组比较:S组T_(2)时心率和MAP降低(P<0.05),T_(1)~T_(3)时pH值升高、PaCO_(2)降低(P<0.05),T_(2)、T_(3)时血糖、皮质醇、IL‑6降低(P<0.05),T_(3)时CRP降低(P<0.05)。各指标其余时点间差异无统计学意义(P>0.05)。H组因术中P_(ET)CO_(2)>80 mmHg暂停操作的有3例,S组0例。结论在无痛FOB治疗气道管理中,高频‑常频叠加喷射通气效果优于单纯高频喷射通气。     

高频喷射通气对吸入性损伤犬呼吸气流与气体交换的影响

目的 观察犬吸入性损伤时呼吸气流对气体交换的影响。方法 用三维粒子动态分析仪测定犬自主呼吸时吸气和呼气流速。将实验动物通入高压蒸气５秒后随机进行五种不同条件高频喷射通气，每种通气方式通气２０分钟，并根据公式Ｒｅ＝Ｖｒｐ／η计算出雷诺数，同时采取动脉血标本，观察Ｐ２－ＣＯ２、ＰａＯ２、ＰＩＰ的变化。结果（１）自主呼吸时吸气为层流，呼气可有为层流，也可能为涡流；（２）高频喷射通气（ＨＦＪＶ）时呼气和吸     

Tracheobronchial dilating effect of high frequency jet ventilation

Effect of high frequency jet ventilation (HJFV) on tracheobronchial tone was examined in anesthetized dogs. Changes in intraluminal pressure of water-filled endotracheal cuff (Pcuff) were used as an indicator of tracheal smooth muscle tone. Animals were initially ventilated with conventional mechanical ventilation (CMV) to maintain normal Pa_{CO 2}. HFJV (2.0Hz.) was then applied to each animal in such a way to maintain the same mean airway pressure and Pa_{CO 2} as in CMV.Immediately after changing CMV to HFJV, Pcuff decreased significantly and remained decreased during the period of HFJV. After changing HFJV to CMV, Pcuff gradually returned to its previous level. Histamine-induced tracheobronchial constriction was partially released by HFJV as shown by a decrease in Pcuff and airway resistance (Raw) and by an increase in static lung-thorax compliance (Cst) measured immediately after the cessation of HFJV.These results suggest that HFJV has a tracheobronchial dilating action, presumably mediated by pulmonary stretch reflex, and this may be one of the mechanisms of an increase in mucous secretion and of other reported favorable effects of HFJV in some types of respiratory failure.(Toyooka H, Amaha K, Yokoyama K.: Tracheobronchial dilating effect of high frequency jet ventilation. J Anesth 4: 206–212, 1990)     

Propofol or halothane anaesthesia for children with asthma: effects on respiratory mechanics

Propofol may cause histamine release and alter airway tone and reactivity. Although its use has been reported to be safe in asthmatics, there is a lack of information on its effect on lung function in children with asthma. We measured respiratory mechanics after i.v. or inhalation anaesthesia in 60 children, aged 2-12 yr, with or without asthma. Anaesthesia was induced with propofol 3 mg kg-1, fentanyl 1 microgram kg-1 and atracurium 0.5 mg kg-1 and maintained with an infusion of propofol 10 mg kg-1h-1 and 50% nitrous oxide in oxygen. Halothane was administered subsequently at a concentration of 1 MAC. Respiratory mechanics were measured by applying a single- compartment model using multi-linear regression analysis to calculate dynamic compliance (Crs,dyn) and respiratory system resistance (Rrs), based on: Pao = V/Crs,dyn + V Rrs + PA,EE, where Pao = airway opening pressure, PA,EE = alveolar pressure, V = volume and V = flow. The two groups were comparable in age, weight and ventilation variables (tidal volume and peak pressure). Respiratory mechanics during propofol anaesthesia were comparable in normal and asthmatic children (Rrs = 20.5 X 10(-4) (SD 5.2 X 10(-4)) vs 21.5 X 10(-4) (5.7 X 10(-4)) kPa ml- 1 S-1 (ns) and Crs,dyn = 247.5 (76.51 vs 235.1 (63.8) ml kPa-1 (ns)). Halothane produced a minimal decrease in Rrs and a minimal increase in tidal volume in both groups without changes in Crs,dyn. In conclusion, respiratory mechanics were comparable after propofol anaesthesia in both children with and without asthma. Changes in Rrs after halothane administration were not clinically relevant.      

部分液体通气对吸入性损伤犬的研究

目的 观察部分液体通气(PLV)对吸人性损伤犬呼吸力学、氧合和血流动力学参数的影响.方法 16条健康杂种犬经蒸气吸人造成重度吸入性损伤模型,随机分为对照组和实验组(n=8).实验组经气管导管缓慢注入氟碳液体(12ml/kg体重)行PLV治疗,治疗后30、60、90 min时测定两组犬血气、气道阻力、肺顺应性及血流动力学参数.结果 实验组Pa02呈进行性上升,在各时点与致伤后60 min比较差异有统计学意义(P＜0.05).与对照组比较,实验组各时点的PaO2稍有升高(P＞0.05).两组气道阻力、肺顺应性和血流动力学参数比较,差异均无统计学意义(P＞0.05).结论 PLV有利于吸入性损伤犬的动脉氧合,对血流动力学无明显不利影响.     

Changes in respiratory mechanics during abdominal laparoscopic surgery in children.

We designed this study in order to measure the changes in respiratory mechanics during laparoscopic surgery in children. Ventilation parameters (Flow (Ví) and Peak Pressure (Pmax)) were measured and total respiratory system mechanics (resistance (Rrs) and compliance (Crs)) were derived using multiple linear regression analysis in 11 children aged 8 months to 11 years. The Pmax increased by 26.6% and the Rrs increased by 20.2% whilst the Crs decreased by 38.9% after pneumoperitoneum. These findings suggest that clinically important changes in respiratory mechanics occur as a result of the pneumoperitoneum produced during abdominal laparoscopic surgery.     

高频通气治疗吸入性损伤

High frequency ventilation (HFV) is a kind of lung protective ventilation strategy. High-frequency jet ventilation (HFJV) can decrease the water content, relocate interstitial fluid and accelerate lymph flow in the lung of dogs with smoke inhalation injury. HFJV can effectively improve breathing mechanics and gas exchange in dogs with smoke inhalation injury. Clinical application also proves that HFV is efficient in treatment of inhalation injury.     

Carinal resection with two high-frequency jet ventilation delivery systems

A 76-yr-old man underwent carinal resection for squamous cell carcinoma through the right posterolateral thoracotomy approach. Ventilation was maintained by the use of two highfrequency jet ventilators, each attached to a separate catheter during the time of resection and reconstruction of the tracheal carina. These catheters were introduced through the endotracheal tube and positioned into the left and right main bronchi at the beginning of the tracheal resection. Then, conventional ventilation was replaced by high-frequency jet ventilation (HFJV) with different ventilatory variables for each lung. During two-lung jet ventilation there was good oxygenation, normocapnia and no cardiovascular complications. The principle advantage of using two separate high-frequency ventilators is that it allows for maximum ventilatory efficiency with lungs of different compliance.     

Efficacy of high-frequency jet ventilation in cardiac tamponade

To evaluate the effects of high-frequency jet ventilation (HFJV) (f = 60, 120 breaths/min) and conventional mechanical ventilation (CMV) (f = 10, 20) during equivalent conditions of cardiac tamponade, stroke index (SI), intrapericardial pressure (IPP), airway pressure (P(aw)), and cardiac pressures were measured in anesthetized, paralyzed, chest-closed dogs with the same levels of PaCO2. Cardiac tamponade was produced by infusing normal saline into the intrapericardial space to increase IPP to either 8 mm Hg (group 1, n = 8) or 12 mm Hg (group 2, n = 8). Stroke index in group 1 was 7.3 +/- 0.8 during CMV (f = 10), 8.1 +/- 0.7 during CMV (f = 20), 10.9 +/- 1.4 during HFJV (f = 60), and 10.7 +/- 1.2 (mL.beat-1.m-2) during HFJV (f = 120). Stroke index in group 2 was 4.1 +/- 0.7, 5.1 +/- 0.5, 7.2 +/- 0.5, and 6.7 +/- 0.5 (mL.beat-1.m-2), respectively. In both IPP groups, stroke index values during HFJV were significantly higher than during CMV; however, there were no significant differences in mean left and right atrial transmural pressures between HFJV and CMV. Peak IPP, mean P(aw), and peak P(aw) during HFJV were significantly lower than those during CMV. The results indicate that HFJV with lower mean and peak Paw, and with lower mean and peak IPP, can result in higher cardiac output than CMV in cardiac tamponade. Thus, HFJV may be superior to CMV in the clinical management of cardiac tamponade.     

Hemodynamic effects of high-frequency jet ventilation

The hemodynamic effects of high-frequency jet ventilation (HFJV) and conventional ventilation were compared in normovolemic and functionally hypovolemic dogs. In normovolemic animals, no differences in hemodynamic function were found among spontaneous ventilation, conventional ventilation, and HFJV. When venous return was impaired by 15 cm H2O PEEP, cardiac index and stroke index were 25% higher with HFJV than with conventional ventilation (P less than 0.05). In another study with PEEP, conventional ventilation was compared to spontaneous ventilation, HFJV synchronized to five different parts of the cardiac cycle, and asynchronous HFJV. Heart rate was 15% lower and mean arterial pressure was 26% lower with conventional ventilation than with HFJV modes (P less than 0.05). There were no differences between synchronous and asynchronous HFJV. These results indicate that hemodynamic dysfunction may be less likely with HFJV than conventional ventilation. No advantage of synchronizing jet pulsations to a specific part of the cardiac cycle could be demonstrated.