Therapy of acute massive pulmonary embolism associated with Klippel-Trenaunay syndrome

Acute massive pulmonary embolism (PE) is a life-threatening event. Before the era of cardiopulmonary bypass, acute pulmonary embolectomy had been historically attempted in patients with severe hemodynamic compromise. The Klippel-Trenaunay syndrome (KTS) represents a significant life-long risk for major thromboembolic events. We present two young patients with Klippel-Trenaunay syndrome who survived surgical embolectomy after massive PE and cardiopulmonary resuscitation, with good postoperative recovery. Even though the role of surgical embolectomy in massive PE is not clearly defined, with current technology it can be life saving and can lead to a complete recovery, especially in young patients as described in this study.     

Pathophysiology of pulmonary arterial hypertension

The mechanisms leading to elevations in precapillary pulmonary vascular resistance are complex and likely involve multiple pathways, but the histopathologic sequelae of these processes are restricted to a few findings, primarily neoangiogenesis, intimal and smooth muscle proliferation, vasoconstriction, and/or in situ thrombosis. Regardless of the etiology of pulmonary hypertension, abnormalities in endothelial function are often observed and likely play a central role in mediating structural changes.     

Anesthetic management of children with pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is associated with significant perioperative risk for major complications, including pulmonary hypertensive crisis and cardiac arrest. Several mechanisms of hemodynamic deterioration, including acute increases in pulmonary vascular resistance (PVR), alterations of ventricular contractility and function and coronary hypoperfusion can contribute to morbidity. Anesthetic drugs exert a variety of effects on PVR, some of which are beneficial and some undesirable. The goals of balanced and cautious anesthetic management are to provide adequate anesthesia and analgesia for the surgical procedure while minimizing increases in PVR and depression of myocardial function. The development of specific pulmonary vasodilators has led to significant advances in medical therapy of PAH that can be incorporated in anesthetic management. It is important that anesthesiologists caring for children with PAH be aware of the increased risk, understand the pathophysiology of PAH, form an appropriate anesthetic management plan and be prepared to treat a pulmonary hypertensive crisis.     

血液透析患者并发肺动脉高压的临床分析

目的　探讨慢性肾衰竭血液透析（HD）患者并发肺动脉高压（PAH）的发生率和临床特点,以便早期诊断PAH并进行干预。 方法　收集首都医科大学附属北京朝阳医院肾内科2000年1月至2007年12月资料完整的维持性血液透析（MHD）患者184例的临床资料,进行回顾性分析。PAH的确定按照超声心动图诊断标准。 结果　184例中并发PAH 65例（35.3%）,其中男34例,女31例,平均年龄（56.84±14.58）岁,透析龄（29.69±21.61）个月。PAH组患者使用动静脉内瘘61例,深静脉置管4例。PAH组静息肺动脉收缩压（PASP）为（44.56±8.25） mm Hg（1 mm Hg＝0.133 kPa）,显著高于无PAH组的（30.28±3.92）mm Hg（P < 0.01）。PAH组与无PAH组每周透析时间、透析间期体质量增加、Hb、Hct、右室横径、右房横径、右房长径和肺动脉内径等指标差异均有统计学意义（P < 0.05）。对以上因素进行Logistic回归分析显示,MHD并发PAH与贫血、透析间期体质量增加和右房横径显著相关（P < 0.05）。 结论　HD患者并发PAH并不少见,60%为轻度PAH,但临床症状隐匿,应提高警惕以早期诊断和早期干预。定期对HD患者行超声心动图检查对筛选PAH非常必要。     

Current therapies for pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a progressive disease of the pulmonary vasculature, characterized by relentless deterioration and death. Patients with PAH are known to be at increased risk for anesthetic complications and surgical morbidity and mortality. However, outcomes in patients have improved with the recent development of new drug therapies. The 3 major drug classes for treatment of PAH are prostanoids, endothelin-receptor antagonists, and phosphodiesterase-5 inhibitors. In this review, the authors provide an overview of each drug class, its mechanism of action, indications, and current supportive literature. Surgical and interventional treatments of PAH, including atrial septostomy, pulmonary thromboendarterectomy, and transplantation, are briefly reviewed, and the rationale, indications, and selection criteria for each are discussed. Although available medical and surgical therapies for PAH have improved patient outcomes, acute decompensated right heart failure (RHF) remains a common and challenging complication of PAH. The authors review this topic and provide an outline of the general pathophysiology of RHF and an approach to its management.     

Pathology of small blood vessel disease in hypertension

A pathogenic role for arterioles in hypertension has been postulated for many decades. Renal arteriolonecrosis, myointimal hyperplasia, and hyaline arteriolosclerosis are anatomic correlates of hypertension. The pathogenesis of these lesions is discussed as is contribution of these lesions to the perpetuation of hypertension. The importance of the extracellular matrix in the initiation and development of hyaline arteriolosclerosis is presented and correlated with the hemodynamic and pathophysiologic consequences of increased transmural pressure. The possibility of aiming therapy at arresting or ameliorating arteriolar disease is presented.     

Diltiazem reduces pulmonary arterial pressures in recurrent pulmonary hypertension associated with pulmonary hypoplasia.

BACKGROUND/PURPOSE: Recurrent pulmonary hypertension in the neonatal population is an unusual event with dire consequences. Pulmonary hypertension seen in association with pulmonary hypoplasia may be refractory to conventional medical management. The effect of the calcium channel antagonist diltiazem was studied in five patients with severe pulmonary hypertension. METHODS: A retrospective review of the hospital records was performed to determine the efficacy of diltiazem for refractory pulmonary hypertension. All five patients experienced and did not respond to maximal conventional therapy, which included inhaled nitric oxide, intravenous nitrates, and extracorporeal membrane oxygenation (ECMO). Right ventricular pressures were determined by transthoracic echocardiograms and were used to document improvement in the pressure gradients. Statistical analyses were performed using a paired Student's ttest. A P value of less than .05 was considered significant. RESULTS: Diltiazem significantly reduced the right ventricular systolic pressure (RVSP) from 82 +/- 8.4 mm Hg to 58.4 +/- 7 mm Hg (P = .008). Two patients died; one had a large ventricular septal defect, and the other suffered multisystem organ failure secondary to sepsis. The surviving patients were weaned off diltiazem and did not experience recurrent pulmonary hypertension. CONCLUSIONS: In cases of pulmonary hypoplasia with recurrent pulmonary hypertension, diltiazem may be considered as a therapy. A multicenter prospective trial is advocated.     

The Klippel-Trenaunay syndrome.

The Klippel-Trenaunay Syndrome is a triad of congenital anomalies characterized by a vascular naevus, varicose veins and hypertrophy of soft tissue and bone. A number of patients affected with this rare syndrome need amputation. In this paper the systemic problems, stump complications and prosthetic difficulties of four amputees with Klippel-Trenaunay syndrome are outlined. The period of follow-up ranged from 10 to 24 years after amputation.     

Klippel-Trenaunay syndrome associated with urinary tract hemangiomas.

Genitourinary hemangiomas in 2 children with Klippel-Trenaunay syndrome are reported. The presence of cutaneous hemangiomas should alert urologists to the possibility of urinary tract hemangiomas inpatients with gross hematuria. Transurethral manipulation of bladder hemangiomas should be avoided because of the danger of excessive hemorrhage, the treatment of choice being partial cystectomy.     

Pulmonary arterial hypertension in patients with sleep apnoea syndrome

BACKGROUND: Pulmonary arterial hypertension (PAH) in patients with sleep apnoea syndrome (SAS) is classically ascribed to associated chronic obstructive pulmonary disease (COPD). The aim of this retrospective study was to evaluate the possible occurrence of PAH as a complication of SAS in patients without COPD. METHODS: Right heart catheterisation was performed in 44 patients with SAS and without COPD confirmed by polysomnography (apnoea index >5/h) admitted for the administration of nasal continuous positive airway pressure (CPAP). RESULTS: Precapillary PAH, defined as mean pulmonary arterial pressure of >20 mm Hg with pulmonary capillary wedge pressure <15 mm Hg, was observed in 12/44 (27%) patients with SAS. There were no significant differences in apnoea index between patients with (PAH+) and those without PAH (PAH-) (42.6 (26.3) versus 35.8 (21.7) apnoeas/h). The PAH+ group differed significantly from the PAH- group in the following respects: lower daytime arterial oxygen tension (PaO(2)) (9.6 (1.1) versus 11.3 (1.5) kPa, p=0.0006); higher daytime arterial carbon dioxide tension (PaCO(2)) (5.8 (0.5) versus 5.3 (0.5) kPa, p=0.002); more severe nocturnal hypoxaemia with a higher percentage of total sleep time spent at SaO(2) <80% (32.2 (28.5)% versus 10.7 (18.8)%, p=0.005); and higher body mass index (BMI) (37.4 (6) versus 30.3 (6.7) kg/m(2), p=0.002). The PAH+ patients had significantly lower values of vital capacity (VC) (87 (14)% predicted versus 105 (20)% predicted, p=0.005), forced expiratory volume in one second (FEV(1)) (82 (14)% predicted versus 101 (17)% predicted, p=0.001), expiratory reserve volume (40 (16)% predicted versus 77 (41)% predicted, p=0.003), and total lung capacity (87 (13)% predicted versus 98 (18)% predicted, p=0.04). Stepwise multiple regression analysis showed that mean pulmonary artery pressure (PAPm) was positively correlated with BMI and negatively with PaO(2). CONCLUSION: Pulmonary arterial hypertension is frequently observed in patients with SAS, even when COPD is absent, and appears to be related to the severity of obesity and its respiratory mechanical consequences.