Method of assessing the reproducibility of blood flow measurement: factors influencing the performance of thermodilution cardiac output computers

Measurements of blood flow by three different makes of thermodilution cardiac output computer in an artificial circulation were analysed by linear regression against absolute flow measured by timed blood volume collection. For each computer the horizontal distance between the 95% confidence limits for a single prediction was calculated at a standard flow rate of 5 litres per minute. This measurement represents the range of flow rates that could give rise to an identical measurement and provides a summary of the reproducibility of the computer's results and its ability to detect a change of flow rate. This measurement was used to evaluate the effect on each computer's performance of pulsatile or continuous flow, injectate volume, and injectate temperature. With continuous flow the optimum results were 1.8, 0.85, and 0.85 litres per minute and with pulsatile flow they were 1.3, 1.05, and 1.65 litres per minute. There was generally a deterioration in performance when pulsatile flow was evaluated. Under the conditions of the experiment optimum performance in both flow modes was obtained with 5 ml of ice cold injectate, but these findings cannot necessarily be extrapolated to the clinical situation. With pulsatile flow the overall range of blood flows that could give rise to identical measurements were for each computer 2.0, 1.5, and 3.1 litres per minute, corresponding to 40, 30, and 62% changes of the standard flow rate of 5 litres per minute.     

003 胺碘酮可作为心房纤颤转复为窦性心律的首选药物

在美国，胺碘酮仅被批准用于治疗致命性室性心律失常，而在其他国家，尤其是南欧，也被广泛用于心房纤颤(Af)的治疗。然而有关胺碘酮复律效果报道不一，其成功率在16％～92％。本文前瞻性随机对照研究胺碘酮作为Af复律的首选药物的疗效及安全性。 连续208例症状性Af，男性102例，女性106例，年龄27～78(65±10)岁。将受试者随机分为胺碘酮治疗组与安慰剂组。胺碘酮用法：300mg静脉注射，持续1小时，然后以20mg/kg静脉滴注，持续24小时，继之口服200mg，tid，共1周，400mg/d共3周。如果受试者此前未用地高辛，则给予地高辛0.5mg静脉注射，2小时后再静脉注射0.25mg，继之静脉注射0.25mg，q6h，共24小时，此后调整地高辛剂量以维持治疗剂量的血清浓度，对Af持续48小时以上或持续时间不明、未用抗凝药物者均应用醋硝香豆素(acenocoumaro1)，至少21天，复律成功者继续用药21天，未成功者用药时间不定。本研究将Af持续1个月以上者定义为慢性Af，＜24小时者定义为新近发作Af，其余定义为持续性Af。     

A near-fatal reaction during granulocyte transfusion of a neonate

Although reactions to granulocyte transfusions in neonates are rarely reported, we observed a near-fatal pulmonary reaction, presumably due to white cell antibodies, in a neonate with Rh hemolytic disease. The hemolytic disease was being treated with exchange transfusions, and at 2 days after the infant's birth, bacterial sepsis was suspected and granulocyte transfusions were begun. The first granulocyte transfusion (Day 3) was uneventful. Five minutes after the beginning of the second granulocyte transfusion (Day 4), severe respiratory distress, hypotension, bradycardia, cyanosis, and acidosis suddenly occurred. The infant's serum obtained after the reaction contained granulocytotoxic and B-lymphocytotoxic antibodies that reacted with leukocytes from the second granulocyte donor. Antibodies could not be detected either in the initial infant serum or in maternal serum. However, an antileukocyte antibody was present in the serum of a parous woman donor. We used plasma from this woman to prepare reconstituted whole blood for the exchange transfusion that we performed immediately preceding the second granulocyte transfusion. Despite the sequence of events, an irrefutable cause-and-effect mechanism could not be established because the properties of the donor and neonatal antibodies were similar, but not identical. However, this catastrophic event emphasizes both the potential for adverse effects of granulocyte transfusions in neonates and the need for caution when transfusing blood from parous women.     

Anesthesia for children in Sub-Saharan Africa – a description of settings, common presenting conditions, techniques and outcomes

Anesthesia in developing countries deserves special attention. The most common technique is general anesthesia (with spontaneous or manually assisted ventilation). Nonmedical anesthetists with limited training and supervision and lacking the most common drugs and anesthetic equipment administer anesthesia, usually for emergency surgery. There are important safety issues, especially for pediatric anesthesia. Regarding pediatric surgery, the major workload is due to abdominal emergencies, mainly neonatal bowel obstruction or peritonitis due to typhoid perforation. The morbidity and mortality rate for these conditions is high.     

What Can Be Expected of Balloon Aortic Valvuloplasty in Adults?

Introduced more than 15 years ago, balloon aortic valvuloplasty (BAV) has clearly delineated indications and limitations. Although, aortic valve replacement is undoubtedly the treatment of choice for healthy patients with aortic stenosis, BAV has been demonstrated as a valuable and safe palliative procedure for patients considered too risky or old for current day surgery. Between January 1991 and December 1999, 858 patients (mean age 76 ± 11 years, 479 [57%] women) underwent BAV at our center. Indications for BAV were contraindication to surgery in 16.2% of the patients, high risk in 40.4%, refusal of surgery in 10.7%, personal decision in 18.5%, and other in 14.2%. The mean gradient decreased from 65 ± 23 to 27 ± 12 mmHg and the valve area increased from 0.56 ± 0.19 cm² to 1.0 ± 0.38 cm². Eleven (1.1%) patients died during the procedure. The other severe complications were complete AV block in 18 (1.8%) patients, stroke in 8 (0.8%), tamponade in 6 (0.6%), and massive aortic insufficiency in 4 (0.4%). In conclusion, BAV does not replace valve replacement, even in the elderly. All those who can be operated on, should be. However, if surgical intervention is not considered reasonable, BAV offers good immediate results with an acceptable complication rate. Furthermore, previous published series have demonstrated that BAV is particularly indicated in specific subgroups, such as very old patients with high operative risk, end-stage heart failure, cardiogenic shock, or general anesthesia for noncardiac surgery.     

Method of assessing the reproducibility of blood flow measurement: factors influencing the performance of thermodilution cardiac output computers.

Measurements of blood flow by three different makes of thermodilution cardiac output computer in an artificial circulation were analysed by linear regression against absolute flow measured by timed blood volume collection. For each computer the horizontal distance between the 95% confidence limits for a single prediction was calculated at a standard flow rate of 5 litres per minute. This measurement represents the range of flow rates that could give rise to an identical measurement and provides a summary of the reproducibility of the computer's results and its ability to detect a change of flow rate. This measurement was used to evaluate the effect on each computer's performance of pulsatile or continuous flow, injectate volume, and injectate temperature. With continuous flow the optimum results were 1.8, 0.85, and 0.85 litres per minute and with pulsatile flow they were 1.3, 1.05, and 1.65 litres per minute. There was generally a deterioration in performance when pulsatile flow was evaluated. Under the conditions of the experiment optimum performance in both flow modes was obtained with 5 ml of ice cold injectate, but these findings cannot necessarily be extrapolated to the clinical situation. With pulsatile flow the overall range of blood flows that could give rise to identical measurements were for each computer 2.0, 1.5, and 3.1 litres per minute, corresponding to 40, 30, and 62% changes of the standard flow rate of 5 litres per minute.     

A retrospective study on chemical and radioactive synovectomy in severe haemophilia patients with recurrent haemarthrosis

Between 1970 and 1994, 116 chemical and 90 radioactive synovectomies were performed in 107 patients with severe haemophilia and two with type 3 von Willebrand's disease. The products used were osmic acid (OA) in 100 cases, 90-Yttrium in 35 cases, 186-Rhenium in 48, 169-Erbium in two, hexacetonide triamcinolone in 16 and radioactive gold in five cases. The use of radioactive colloids is not allowed in France in patients under 15 years of age. Twenty-nine patients had more than one synovectomy per joint. All patients were evaluated for 6 months post-synovectomy, using both a clinical and a radiological score. Six months after synovectomy, a good or excellent result was obtained for 81% of the joints treated with isotopes, compared with 44% of those treated with OA, P<0.001. This superiority of isotopes over osmic acid was still observed after 6 months for the 89 joints that were re-evaluated, with follow-up ranging from 1 to 9 years. It was possible to calculate a radiological score in 84 cases. With OA the best results were from the joints with the lowest scores pre-synovectomy (<7). No correlation could be established between the clinical and the radiological scores, due to the small size of the sample. In summary: (1) chemical and radioactive synovectomy are simple and safe procedures for haemophilic arthropathy, (2) in our series, after 6 months the efficacy of isotopic synovectomy was greater than that of chemical synovectomy, and this benefit seems to persist after 6 months, and up to 9 years in the group of patients with longer-term follow-up.