人工髋关节置换并发假体周围骨折的临床分析

目的：分析人工髋关节置换术中、术后发生假体周围骨折的原因,探讨其预防措施和治疗方法。方法：总结自1995年7月至2006年8月总共640例人工髋关节置换术患者,其中18例发生假体周围骨折,术中骨折11例（股骨距骨折7例,假体柄下端骨折4例）,术后骨折7例（假体柄下端、远端骨折）,男性12例,女性6例,平均年龄68岁（51～79岁）,按照髋关节假体置换术后骨折的AAOS分型Ⅰ型1例,Ⅱ型6例,Ⅲ型4例,Ⅳa型4例,Ⅳb型2例,Ⅴ型1例,Ⅵ型2例,其中术中假体周围骨折11例有10例予立即内固定,1例（Ⅱ型）股骨距劈裂骨折无明显移位未做内固定,仅延迟下地负重时问;术后假体周围骨折7例有4例在两周内行手术内固定,2例合并假体松动而采用全髋关节翻修术,1例（Ⅵ型）假体远端骨折因身体原因无法手术而采取保守治疗予以骨牵引4周后改石膏外固定。结果：术后平均随访时间15．2个月（6—42个月）,15例患者骨折均达到骨性愈合,2例发生骨折延迟愈合,保守治疗的1例患者术后6个月拍片示骨折畸形愈合,术后8个月因内科疾病死亡。Harris评分平均80分（67-92分）。结论：术中暴力、股骨髓腔发育异常、假体型号过大、骨质疏松是术中假体周围骨折发生的主要原因,骨溶解、假体松动、骨质疏松加外伤是术后发生假体周围骨折的主要原因,根据不同分型采用不同的治疗方法以促进骨折愈合,稳定假体,减少卧床时间和并发症（尤其对高龄患者更为重要）,尽早恢复功能。     

人工髋关节置换并发假体周围骨折的临床分析

目的：分析人工髋关节置换术中、术后发生假体周围骨折的原因,探讨其预防措施和治疗方法。方法：总结自1995年7月～2006年8月总共640例人工髋关节置换术患者,其中18例发生假体周围骨折,术中骨折11例（股骨距骨折7例,假体柄下端骨折4例）,术后骨折7例（假体柄下端、远端骨折）,男性12例,女性6例,平均年龄68岁傅1～79岁）,按照髋关节假体置换术后骨折的AAOS分型I型1例,Ⅱ型6例,Ⅲ型4例,Ⅳa型4例,Ⅳb型2例,Ⅴ型1例,Ⅵ型2例,其中术中假体周围骨折11例有10例子立即内固定,1例（Ⅱ型）股骨距劈裂骨折无明显移位未做内固定,仅延迟下地负重时间;术后假体周围骨折7例有4例在两周内行手术内固定,2例合并假体松动而采用全髋关节翻修术,l例（vI型）假体远端骨折因身体原因无法手术而采取保守治疗予以骨牵引4周后改石膏外固定。结果：术后平均随访时间15．2个月（6～42个月）,15例患者骨折均达到骨性愈合,2例发生骨折延迟愈合,保守治疗的1例患者术后6个月拍片示骨折畸形愈合,术后8个月因内科疾病死亡。Harris评分平均80分（67。92分1。结论：术中暴力、股骨髓腔发育异常、假体型号过大、骨质疏松是术中假体周围骨折发生的主要原因,骨溶解、假体松动、骨质疏松加外伤是术后发生假体周围骨折的主要原因,根据不同分型采用不同的治疗方法以促进骨折愈合,稳定假体,减少卧床时间和并发症（尤其对高龄患者更为重要）,尽早恢复功能。     

钛-镍记忆合金接骨板治疗髋关节置换术后假体柄周围骨折

目的 探讨钛-镍记忆合金接骨治疗髋关节置换术后假体柄周围骨折的临床疗效.方法对10例髋关节置换术后假体柄周围骨折采用切开复位钛-镍记忆合金接骨板进行治疗.结果 10例经3～24个月随访,术后4～8个月骨折正常愈合,肢体功能恢复到伤前状态,无一例出现假体松动,根据股骨干骨折疗效评定标准,本组治愈8例.结论钛-镍记忆合金接骨板治疗髋关节置换术后假体柄周围骨折,具有创伤小,操作简单,固定可靠,对骨折端破坏小,利于骨折愈合等优点,是一种行之有效的治疗髋关节置换术后假体周围骨折的方法.     

Jumbo臼杯治疗全髋置换术后伴假体松动的假体周围骨折

[目的]评估Jumbo金属臼杯治疗初次全髋置换术后伴假体松动的髋臼假体周围骨折的治疗效果。[方法]回顾性分析2013年7月～2018年1月手术治疗的全髋关节置换术后伴假体松动的髋臼假体周围骨折患者9例,男性1例,女性8例,年龄32～76岁,平均(68.72±8.03)岁。按照Paprosky髋臼假体周围骨折分型,Ⅲb型4例,Ⅳa型4例,Ⅳb型1例。选择较末次磨挫大1～2 mm的Jumbo金属臼杯并适当螺钉固定。采用疼痛视觉模拟评分(VAS)评价术后疼痛情况,采用Harris评分评估髋关节功能。[结果] 9例患者手术顺利,平均手术时间(104.57±23.89) min;平均术中出血量(245.38±85.89) ml。平均随访时间(24.89±10.32)个月,随术后时间推移,疼痛逐渐缓解,VAS评分显著降低(P0.05),髋关节Harris评分显著增加(P0.05)。术后影像学显示髋臼骨折均愈合良好,骨折愈合时间(16.38±2.01)周,髋臼假体位置良好,未见假体松动、移位。[结论]对于初次全髋置换术后伴假体松动的髋臼假体周围骨折,使用Jumbo金属臼杯既可满足骨折及假体牢靠固定,又可使翻修术操作简单有效,是可行的治疗方案。     

生物型和骨水泥型股骨假体全髋关节置换术治疗老年骨质疏松性股骨颈骨折的临床效果对比

目的：对比老年骨质疏松股骨颈骨折使用生物型股骨假体柄与骨水泥型股骨假体柄行全髋关节置换术治疗效果。方法对本组进行老年骨质疏松股骨颈骨折100例（100髋）进行的全髋关节置换术根据手术方式分为A组（股骨假体柄骨水泥型全髋关节置换术,60髋）, B组（股骨假体柄生物型全髋关节置换术,40髋）。对比两组髋关节功能、关节活动度、髋关节影像学特点及术后疼痛情况。结果老年骨质疏松股骨颈骨折行全髋关节置换术,采用生物型股骨假体柄与骨水泥型股骨假体柄的全髋关节置换术临床疗效对比差异显著（ P＜0.05）。结论对于老年骨质疏松股骨颈骨折行全髋关节置换术,应用骨水泥型者股骨假体柄术后近期疗效明显优于生物型,但它有诱发深静脉血栓栓塞和骨水泥危象的风险。     

Solution广泛多孔钛涂层长柄假体结合钢丝环扎固定治疗股骨头置换术后Vancouver B2型假体周围骨折的中期随访

背景：股骨头置换术后Vancouver B2型假体周围骨折多伴有假体松动,患者年龄大,并存疾病多,骨质条件差,围手术期处理及手术技术难度大,并发症发生率高。 目的：评价Solution广泛多孔钛涂层长柄假体结合钢丝环扎固定治疗股骨头置换术后Vancouver B2型假体周围骨折的中期疗效。 方法：回顾分析2008年1月至2010年12月我科收治的14例股骨头置换术后Vancouver B2型假体周围骨折患者的临床资料,其中男6例,女8例,年龄66-80岁,平均70.3岁。所有患者均采用骨折切开复位钢丝环扎固定结合Solution股骨柄进行翻修手术。末次随访时进行Harris髋关节评分（术前由于骨折未能进行Harris髋关节评分）;术前,术后3、6、12个月及末次随访时摄X线片,用于评价骨折复位及愈合,假体初始固定及中期生存情况。 结果：共16例患者,1例术后3年死于肺癌,1例失访,14例获得随访,随访时间3-5年,平均4.2年。末次随访时Harris评分88.7分。X线显示骨折复位,股骨柄超过骨折远端的固定长度超过5 cm,与股骨压配良好。骨折愈合时间3-6个月,平均（3.8＆#177;1.3）个月。末次随访时未见股骨柄松动、下沉。无感染、深静脉血栓形成和肺栓塞。 结论：Solution股骨柄结合钢丝环扎固定治疗股骨头置换术后Vancouver B2型假体周围骨折中期疗效好,其远期结果有待于进一步的随访。     

髋关节置换术后并发症X线临床分析

[目的]分析髋关节置换术后并发症X线表现,探讨髋关节置换术失败及并发症的成因与临床的因果关系.[方法]回顾性分析1999年5月～2006年6月本院所诊治的160例髋关节置换术患者的临床及CR图像资料.[结果]160例病例中4例发生脱位,2例假体柄固定处发生骨折,7例发生假体松动,继发性骨化性肌炎2例,术后感染1例.[结论]假体选择、安放不当、使用不当以及操作不规范是髋关节置换术后并发症的主要原因.     

全髋关节置换假体柄周围骨折的治疗

目的 :回顾性研究全髋关节置换假体柄周围骨折的治疗及预防。方法 :将本院近年收治的全髋置换假体柄周围骨折的 8例病例按Vancouver分类方法进行分类 ,其中A1型 3例 ,B1型 3例 ,B2型 1例 ,B3型 1例 ,分别用钢丝环扎固定 ,异体皮质骨板加钢丝环扎 ;骨水泥长柄假体翻修。结果 :术后随访 8～ 18个月 ,骨折愈合 ,假体固定可靠。结论 :全髋关节置换术后假体柄周围骨折用Vancouver分类方法分类 ,简单、适用。采用异体皮质骨板与钢丝环扎固定骨折 ,治疗假体柄周围骨折 ,不仅固定可靠而且能促进骨折愈合、恢复骨量。     

全髋关节置换术后股骨假体周围骨折的治疗

目的 探讨人工全髋关节置换术后股骨假体周围骨折的治疗方法及疗效. 方法 回顾性分析2005年7月至2010年6月收治且获得随访的13例人工全髋关节置换术后股骨假体周围骨折,其中男6例,女7例;年龄51 ～ 80岁,平均67岁;骨折按Vancouver分型:B1型3例,B2型5例,B3型3例,C型2例.分别用钢丝或钢缆环扎固定,异体皮质骨板加钢丝环扎;长柄假体翻修;记忆合金环抱器、锁定加压钢板固定.结果 所有患者术后随访9 ～ 30个月,平均16个月.骨折均愈合,时间4～7个月,平均4.8个月.患者无感染、畸形愈合、假体松动脱位、内固定断裂和深静脉血栓形成.根据Harris髋关节功能评分:优7例,良5例,可1例. 结论 全髋关节置换术后假体周围骨折的治疗方案需结合骨折部位、假体有无松动、局部骨质量、身体状况而制定,原则是移位骨折要进行牢固固定、松动假体要进行翻修、严重骨缺损需要植骨处理.     

生物型加长柄半髋关节置换治疗高龄股骨转子间骨折

目的 探讨生物型加长柄半髋关节置换治疗高龄骨质疏松性股骨转子间骨折的疗效。方法 采用生物型加长柄半髋关节置换治疗24例高龄骨质疏松性股骨转子间骨折患者。记录手术时间、术中出血量、术后首次负重时间、骨折愈合时间及术后并发症发生情况，采用髋关节功能Harris评分评价疗效。结果 术后死亡3例；21例获得随访，时间8～12个月。手术时间40～70 min,术中出血量200～500 ml。术后首次负重时间3～14 d。骨折愈合时间45～85 d。切口均一期愈合，无脂肪栓塞、假体周围骨折、关节脱位、假体松动下沉等并发症发生。末次随访时，髋关节功能Harris评分为74～83分，其中良15例，可6例，优良率15/21。结论 生物型加长柄半髋关节置换治疗高龄骨质疏松性股骨转子间骨折可尽早恢复髋关节功能，减少并发症的发生，早期疗效较好。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.     

Intraoperative autotransfusion is associated with modest reduction of allogeneic transfusion in prosthetic hip surgery

Background: The efficacy of intraoperative salvage and washing of wound blood and the predictors of allogeneic red cell transfusions in prosthetic hip surgery are insufficiently known.
Methods: In 96 patients, undergoing primary or revision surgery, salvaged and washed red cells and, if necessary, allogeneic blood were used to keep haematocrit not lower than 33%. The bleeding of red cells during hospital stay was calculated from the red cell balance. The preoperative red cell reserve (millilitres of red cells in excess of a haematocrit of 33%) was estimated and the difference between this volume and the total bleeding of red cells was retrospectively used to classify patients with regard to the need for red cells. Stepwise regression analysis was used to define patient-related variables associated with allogeneic blood transfusion.
Results: Preoperative knowledge of the type of operation (primary, revision), the preoperative red cell reserve, and the body mass could predict roughly half of the need for banked blood (r²=0.45). Only one-third of the total bleeding of red cells was retransfused. For complete avoidance of allogeneic blood, autotransfusion was most effective in patients with a moderate need (0–4 u). However, 32% of such patients required allogeneic blood.
Conclusions: Autotransfusion has a limited efficacy to decrease the need for allogeneic blood, and other blood-saving methods should be added for this purpose. It is difficult to predict the need for allogeneic blood preoperatively.     

缺氧对肾小管上皮细胞分泌外泌体的影响

目的    观察缺氧对肾小管上皮细胞分泌外泌体的影响,探讨外泌体在缺氧致肾脏损伤中的作用及机制。 方法    （1）常氧（21% O₂）及缺氧（1% O₂）分别处理大鼠肾小管上皮细胞（NRK-52E）48 h,收集细胞上清液并使用高速梯度离心法分离外泌体。采用透射电镜、纳米示踪分析、Western印迹、蛋白浓度定量鉴定并比较两组外泌体的基本特性。（2）在共培养实验中,以不同浓度（1、10、50、100、300 mg/L）的常氧外泌体、缺氧外泌体分别干预脂多糖（LPS）诱导的大鼠原代腹腔巨噬细胞,使用实时荧光定量PCR与酶联免疫吸附试验（ELISA）法分别检测巨噬细胞白细胞介素6（IL-6）、肿瘤坏死因子α（TNF-α）、诱导型氮氧化物合酶（iNOS）水平;使用Western印迹法检测巨噬细胞磷酸化（p）STAT/STAT及细胞因子信号传导抑制蛋白1（SOCS1）的蛋白表达;最后,使用实时荧光定量PCR法检测常氧外泌体与缺氧外泌体中炎性反应相关微RNA（microRNA,miR）的表达差异。 结果    （1）离心得到的囊泡具有外泌体典型的结构,粒径小于150 nm,表达外泌体标志蛋白CD63,说明分离得到外泌体。缺氧对肾小管上皮细胞分泌的外泌体形态、粒径分布比例无明显影响,但提高了外泌体的分泌量。（2）缺氧外泌体相比于常氧外泌体促进了LPS诱导的M1型巨噬细胞IL-6、TNF-α、iNOS 的表达和分泌（均P＜0.01）,同时提高STAT的磷酸化水平并减少SOCS1的蛋白表达（均P＜0.01）;对炎性反应相关microRNA检测发现缺氧外泌体中miR-155、miR-27a表达量较常氧外泌体明显升高（P＜0.05）。 结论    缺氧可改变外泌体的生物学功能,表现为协同促进LPS诱导的M1型巨噬细胞的表型转化,这可能是慢性肾脏病微炎性反应状态持续的原因之一。     

In Vitro Function and Durability Assessment of a Novel Polyurethane Heart Valve Prosthesis

Abstract While flexible-leaflet, central-flow prosthetic heart valves promise relief from anticoagulation therapy, they continue to be restricted by inadequate durability. In consequence, a novel trileaflet valve, made entirely from polyurethane, has been developed. A batch of 6 consecutively manufactured polyurethane valves was subjected to hydrodynamic function and accelerated fatigue testing. Computerized data acquisition and control systems have been introduced to improve valve testing methodologies. In terms of hydrodynamic function, the polyurethane valve demonstrates transvalvular pressure gradients similar to those for a bioprosthetic valve (Carpentier-Edwards) and levels of retrograde flow significantly less than those for either the bioprosthetic valve or a bileaflet mechanical valve (St Jude Medical). The equivalent of 10 years of cycling without failure has been exceeded by all 6 polyurethane valves in accelerated fatigue tests with 2 valves remaining intact after 674 million cycles (equivalent to approximately 17 years) in continuing tests. Highspeed photography revealed considerable differences in leaflet motion between valves cycled at accelerated and physiological rates.     

Negative pressure ventilation vs. spontaneous assisted ventilation during rigid bronchoscopy: A controlled randomised trial

Background: Ventilation during interventional rigid bronchoscopy (IRB) under general anaesthesia (jet ventilation, positive pressure ventilation and spontaneous assisted ventilation) may offer some difficulties. This study compares the effectiveness during IRB of intermittent negative pressure ventilation (INPV) and spontaneous assisted ventilation (SAV). Methods: Thirty-eight patients submitted to IRB were randomised into two groups: SAV or INPV. All patients received a total intravenous anaesthesia; INPV patients were paralysed. Pre-and intra-operative arterial blood gases and O₂ flow through a rigid bronchoscope were assessed. The endoscopist applying a subjective score evaluated the operating conditions. Results: Patients of the INPV group, as compared to the SAV group, required a lower dosage of fentanyl (2.6 ± 1.8 (μg · kg^?1· h^?1 vs. 6.6 ± 4.8 μg · kg^?1· h^?1), a lower O₂ supply (3.3 ± 2.8 1/min vs. 11.6 ± 3.4 1/min), a shorter recovery time (5.4 ± 2.9 min vs. 9.8 ± 7.1 min) and no manually assisted ventilation (0 ± 0 vs. 1 ± 1.1 nd?/procedure). Intraoperative PaCO₂ was higher in the SAV (8.1 ± 1.3 kPa) than in the INPV group (5.0 ± 1.6 kPa) and intraoperative pH differed in the two groups (7.26 ± 0.05, SAV vs. 7.47 ± 0.08, INPV). Operating conditions, as assessed by a subjective score, were considered better with INPV than with SAV (4.9 vs. 4.3). Conclusions: As compared to SAV, INPV in paralysed patients during IRB reduces administration of opioids, shortens recovery time, prevents respiratory acidosis, excludes the need for manually assisted ventilation, reduces 02 need and affords optimal surgical conditions. INPV appears a safe, non-invasive and effective ventilatory management during IRB.