肩袖滑囊侧部分撕裂的关节镜手术治疗

目的 探讨关节镜治疗肩袖滑囊侧部分撕裂的手术方法 和临床效果.方法 对2002年6月至2007年12月行关节镜手术的57例肩袖滑囊侧部分撕裂患者进行回顾性分析.男性34例,女性15例,年龄25～71岁,平均年龄49.7岁.左肩15例,右肩34例,涉及优势侧41例.根据Ellman分类标准,Ⅰ度7例,Ⅱ度6例,Ⅲ度36例.术前均拍摄肩关节正位和冈上肌出口位X线片,29例行B超检查,36例行MRI或磁共振血管造影检查.Ⅰ度及Ⅱ度患者行肩峰下间隙减压及肩袖清理术;Ⅲ度患者行肩峰下间隙减压及肩袖修复术.肩袖修复方式:3例直接行断端缝合,26例应用缝合锚钉行肩袖止点重建,7例联合应用断端缝合及缝合锚钉技术.分别在术前和最终随访时采用UCLA肩关节评分标准进行评价.手术前UCLA评分平均为(16.5±2.4)分.其中疼痛评分平均为(2.9±1.0)分,功能评分平均为(5.4±1.2)分,肩关节主动前屈评分平均为(4.3±1.1)分,前屈肌力评分平均为(4.0±0.4)分.结果 49例患者均获得随访,随访时间2～7年,平均48个月.手术后平均UCLA评分为(32.1±3.8)分.其中疼痛评分平均为(8.4±1.7)分,功能评分平均为(9.1±1.4)分,肩关节主动前屈评分平均(4.9±0.2)分,前屈肌力评分平均为(4.8±0.4),与术前比较差异均具有统计学意义(均为P=0.000).优16例,良31例,差2例.47例患者对手术效果表示满意.结论 关节镜手术是治疗肩袖滑囊侧部分撕裂的有效方法 .手术创伤小、恢复快.     

关节镜辅助小切口肩袖修复术治疗肩袖撕裂

目的 探讨关节镜辅助小切口修复术治疗肩袖撕裂的临床效果. 方法 1999年3月～2004年3月应用关节镜辅助小切口修复术治疗肩袖撕裂22例.13例行关节镜检查,小切口肩峰下间隙减压及肩袖修复术;9例行关节镜下肩峰下间隙减压及小切口肩袖修复术.采用UCLA肩评分标准进行评价. 结果 22例随访12～72个月,平均47个月,UCLA评分由术前（14.8±3.8）分升至术后（32.0±4.7）分（t=15.086,P=0.000）.优7例,良13例,可1例,差1例;20例满意. 结论 关节镜辅助小切口修复术是治疗肩袖撕裂的有效方法,操作简单,创伤小.     

肩关节镜下双排与单排缝合治疗肩袖撕裂的疗效比较

目的比较肩关节镜下双排与单排缝合治疗肩袖撕裂的临床疗效。方法研究对象为2016年10月至2019年12月治疗的76例肩袖撕裂患者,36例采用双排缝合技术固定(double row, DR),40例采用单排缝合技术固定(single row, SR)。DR组男12例,女24例,平均年龄(58.75±7.32)岁。SR组男23例,女17例,平均年龄(57.57±7.29)岁。比较两组患者的疼痛视觉模拟评分(visual analogue scale, VAS)、加州大学肩关节评分系统(university of California at Los Angeles, UCLA)评分、美国肩肘外科协会评分(rating scale of the American shoulder and elbow surgeons, ASES)。结果所有患者均获随访,随访时间12～23个月,平均(18±3)个月。两组患者的一般资料比较差异均无统计学意义(P0.05)。与单排缝合组对比,双排缝合组在术后3个月VAS评分更低,差异有统计学意义(P0.05)。两组患者术前、术后6个月、术后12个月VAS评分比较,差异无统计学意义(P0.05);两组患者手术前后UCLA评分、ASES评分比较,差异均无统计学意义(P0.05);两组术后再撕裂等并发症发生率,差异均无统计学意义(P0.05)。结论肩关节镜治疗肩袖撕裂,双排缝合技术和单排缝合技术均可获得较好的临床疗效,对比单排缝合技术,双排缝合技术改善术后早期疼痛的效果更为显著。     

关节镜下Suture Bridge双排法和SCOI单排法缝合修复中型肩袖撕裂的疗效比较

[目的]比较肩关节镜下Suture Bridge双排缝合法和SCOI单排缝合法修复中型大小肩袖撕裂的临床疗效。[方法] 2014年1月～2017年6月,进行了189例肩关节镜下肩袖损伤修复手术。根据纳入和排除标准,纳入了80例患者作为研究对象。根据缝合修复方法不同将患者分为Suture Bride双排法修复组(双排法组) 41例和SCOI修复组(单排法组) 39例。采用美国加州大学洛杉矶分校评分系统(UCLA)评分和美国肩肘外科协会评分系统(ASES)评分评价临床效果。[结果]双排法组和SCOI单排法组平均随访时间分别为(48.82±6.34)、(49.64±7.23)个月。双排法组UCLA评分为(33.92±4.64)分,单排法组UCLA评分为(33.19±5.22)分。两组间差异无统计学意义(P0.05)。双排法组ASES评分为(88.94±5.46)分,单排法组ASES评分为(83.37±6.24)分。两组间差异无统计学意义(P0.05)。[结论]对于中型肩袖撕裂,Suture Bridge双排法修复和SCOI单排法修复缝合UCLA评分和ASES评分无明显差别,均可取得良好的临床疗效     

关节镜下保留肩袖残端修复肩袖撕裂的疗效分析

目的 探讨关节镜下保留肩袖残端修复经肌腱不规则肩袖撕裂的手术方法与临床疗效。方法 回顾性分析自2019-03—2021-03诊治的7例经肌腱不规则肩袖撕裂,MRI显示肱骨大结节附着大量残余的肌腱组织,撕裂位于冈上肌肌腱的体部,撕裂方式不规则,残余的肌腱组织大小不一,采用关节镜下保留肌腱残端的双排缝合桥技术修复肩袖撕裂。结果 7例均获得随访,随访时间平均13.9(12～16)个月。术后所有患者无疼痛、关节肿胀及肩关节活动受限等不适主诉,术后复查肩关节MRI显示肩袖愈合良好,无肩袖再次撕裂发生。术后6周疼痛VAS评分为4～6分,平均5.7分;术后3个月疼痛VAS评分为1～3分,平均1.8分;术后6个月疼痛VAS评分为1～3分,平均1.1分;术后12个月疼痛VAS评分为0～1分,平均0.3分。术后6周肩关节功能UCLA评分为18～26分,平均23.3分;术后3个月肩关节功能UCLA评分为19～31分,平均25.0分;术后6个月肩关节功能UCLA评分为22～29分,平均26.7分;术后12个月肩关节功能UCLA评分为29～35分,平均32.1分。结论 对于肱骨大结节处残余较多肌腱的经肌腱不规则...     

关节镜缝合桥与单排技术治疗肩袖撕裂的病例对照研究

目的:比较关节镜缝合桥技术与单排技术治疗肩袖撕裂的疗效。方法:回顾性分析采用关节镜缝合桥技术与单排技术治疗肩袖撕裂患者的资料,其中缝合桥固定组22例,单排组21例,采用疼痛目测评分(PVAS)、肩关节活动度、美国肩肘外科评分(ASES)、加州大学肩关节评分(UCLA)、复旦大学肩关节评分(FUSS评分)及Constant评分比较两组术前、术后第3 d、术后6月情况,并对术后6月撕裂肩袖的完整性及再撕裂率进行评估。结果:43例均获得随访,缝合桥固定组术后第3 d、术后6月PVAS评分分别为(2.41±1.05)分、(1.12±0.21)分,ASES评分分别为(13.29±1.57)分、(17.33±2.34)分,UCLA评分分别为(23.67±3.07)分、(33.61±3.64)分,Constant评分分别为(76.24±7.36)分、(87.96±8.49)分,FUSS评分分别为(75.43±12.06)分、(88.46±13.07)分,肩关节活动度前屈(160.28±11.57)?、外展(159.38±17.26)?、体侧外旋(48.08±1.81)?,这两时间点各指标值与术前比较,差异均有统计学意义(P0.05);单排组术后第3 d、术后6月PVAS评分分别为(3.52±1.31)分、(2.07±0.35)分,ASES评分分别为(10.25±1.18)分、(15.28±2.17)分,UCLA评分分别为(17.35±3.44)分、(28.57±3.52)分,Constant评分分别为(68.33±7.18)分、(78.69±8.05)分,FUSS评分分别为(68.25±11.36)分、(78.93±12.58)分,肩关节活动度前屈(154.63±12.08)?、外展(148.16±18.57)?、体侧外旋(43.18±10.06)?,这两时间点各指标值与术前比较,差异也有统计学意义(P0.05);缝合桥固定组术后第3 d和术后6月各指标值均高于单排组(P0.05);术后6月,缝合桥固定组2例(9.09%)、单排组3例(14.29%)发生肩袖再撕裂(P=1.000)。结论:关节镜缝合桥技术与单排技术均能治疗肩袖撕裂,前者在肩关节功能活动方面更具有优势,且安全性高,但在复发率方面无明显差异。     

关节镜下双锚钉单排缝合治疗中型肩袖撕裂的疗效分析

目的探讨关节镜下2枚带线锚钉单排缝合修复治疗中型肩袖撕裂的临床疗效。方法回顾性分析自2014-01—2015-12采用关节镜下2枚带线锚钉单排缝合治疗的23例中型肩袖撕裂。结果23例均获得(17.9±5.6)个月随访。末次随访时肩关节疼痛VAS评分较术前明显降低,Constant-Murley及UCLA评分明显增加,肩关节主动前屈上举、外展上举、90°外展位外旋及90°外展位内旋活动度、患侧肩关节外展肌力均明显恢复,差异有统计学意义(P0.05)。结论关节镜下2枚带线锚钉单排缝合修复中型肩袖撕裂术后患肩疼痛明显减轻、功能提高显著,疗效可靠。     

关节镜下单排固定与双排固定治疗肩袖撕裂的Meta分析

目的采用Meta分析的方法比较关节镜下单排缝合与双排缝合治疗肩袖撕裂的临床疗效。方法计算机检索Scopus、Pubmed、Medline和Cochrane数据库,选择比较关节镜下单排缝合与双排缝合治疗肩袖撕裂临床疗效的随机对照研究,依照Cochrane系统评价方法进行质量评价后,对纳入研究进行资料提取,采用Rev Man 5.1软件进行Meta分析,并使用GRADE系统评价证据质量和推荐等级。结果纳入文献7篇。从临床评分看,在术后≤1年的Constant评分(WMD=-3.40,P>0.05)、ASES评分(WMD=0.98,P>0.05)、UCLA评分(P>0.05)以及术后≥2年的Constant评分(WMD=0.82,P>0.05)、ASES评分(WMD=0.64,P>0.05)上,单排组与双排组差异无统计学意义,但术后≥2年的UCLA评分(WMD=0.59,P<0.01)双排组占优;对大小≤3 cm的撕裂,术后Constant评分(P>0.05)、ASES评分(WMD=0.19,P>0.05)、UCLA评分(WMD=0.44,P>0.05)差异无统计学意义,对大小≥3 cm的撕裂,术后Constant评分(P>0.05)差异无统计学意义,而术后ASES评分(WMD=1.45,P<0.05)、UCLA评分(WMD=0.63,P<0.01)双排组占优。从肩关节肌力看(WMD=-0.15,P>0.05),两组术后无统计学差异。从关节活动度看,双排组在前屈(WMD=5.41,P<0.01)、外展(WMD=5.65,P<0.01)方面优于排,但两组在内旋(WMD=0.89,P>0.05)、外旋(WMD=0.36,P>0.05)方面差异无统计学意义。双排组的术后肩袖愈合率(RR=1.20,P<0.01)高于单排组,单排组的术后部分愈合率(RR=0.53,P<0.05)高于双排组,但两组在术后再撕裂率(RR=0.81,P>0.05)方面差异无统计学意义。基于GRADE系统的证据推荐等级评价结果显示:单排组与双排组比较,肩袖愈合率的证据水平为低,推荐意见为弱推荐;部分愈合率的证据水平为低,推荐意见为弱推荐;再撕裂率的证据水平为中,推荐意见为弱推荐。结论双排缝合技术能部分改善肩袖撕裂患者术后肩关节功能,尤其对大小≥3 cm的撕裂,双排缝合技术虽然术后肩袖愈合率较高,但并不能降低术后再撕裂率。上述结论需要更多高质量大样本RCT加以验证。     

肩袖钙化性肌腱炎的关节镜治疗

目的探讨关节镜下钙化灶清理术治疗肩袖钙化性肌腱炎的手术方法和临床效果。方法2003～2006年对14例肩袖钙化性肌腱炎患者行关节镜下钙化灶清理术。男1例,女13例,平均年龄46.1岁。左肩5例,右肩9例,涉及优势侧9例。术前均拍摄肩关节正位和冈上肌出口位X线片,8例行B超检查,8例行MRI检查。全部患者均行关节镜下钙化灶清理术,4例行肩峰成形术,6例行肩袖修复术。分别在术前和最终随访时采用UCLA肩关节评分标准进行评价。结果随访时间1～5年,平均32个月,手术前、后平均UCLA评分分别为(13.3±3.9)和(32.0±2.9)分,差异有统计学意义(t=-12.486,P0.01)。其中疼痛评分平均为(2.3±0.7)和(8.7±1.3)分(t=-17.198,P0.01),功能评分平均为(4.0±1.6)和(8.7±1.5)分(t=-6.600,P0.01),肩关节主动前屈评分平均为(3.1±1.8)和(4.9±0.3)分(t=-3.617,P0.01),前屈肌力评分平均为(3.9±0.5)和(4.6±0.5)分(t=-5.078,P0.01),优7例,良7例。所有患者均对手术效果表示满意。结论关节镜下钙化灶清理术有许多优点,是治疗肩袖钙化性肌腱炎的有效方法。     

关节镜下缝合桥双排固定技术治疗肩袖全层撕裂的初步疗效

目的评价关节镜下应用缝合桥双排固定治疗肩袖全层撕裂的初步临床效果.方法 回顾性分析北京大学第三医院2010年3月至2011年2月间应用关节镜下缝合桥双排固定技术治疗的44例肩袖全层撕裂患者的术后效果（男22例,女22例,术时平均52.3岁）.关节镜下将撕裂按大小分组.分别测定患者术前术后休息和运动时的VAS评分,肩关节前屈、外展和体侧外旋角度,美国加州大学肩关节评分（UCLA）和美国肩肘外科医生评分（ASES）.结果 术后随访时间平均9.7个月,随访率100%.本组病例小撕裂14例（31.8%）,中撕裂21例（47.7%）,大撕裂5例（11.4%）和巨大撕裂4例（9.1%）.休息时VAS评分从术前（6.4±3.4）分降到随访时（0.7±1.5）分,活动时VAS评分从术前的（7.9±2.1）分降到随访时（1.8±1.8）分.手术前后的关节活动度有统计学差异（前屈、外展和体侧外旋的Z值分别为4.789,4.450和4.454,P〈0.01）.UCLA评分由术前的（15.3±4.9）分增加到随访时（30.7±4.0）分;ASES评分由术前的（30.5±17.8）分增加到随访时（84.2±12.6）分,改变均有统计学意义（Z值分别为5.759和5.760,P〈0.01）.患者对手术的满意率是93%,无术中和术后并发症.结论 关节镜下缝合桥双排固定是一种治疗肩袖全层撕裂安全有效的方法,其长期临床效果需进一步研究.     

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.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.     

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.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

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.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

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.