Retained pacemaker leads

Increasingly, functionless pacemaker leads are being abandoned in place because they cannot be safely removed. One hundred eighty-nine intact or partially removed pacemaker leads were abandoned in situ in 152 patients between Jan. 1, 1965, and Dec. 31, 1985. The leads, sometimes several leads in a single patient, were deemed uninfected at the time of abandonment in 137 patients and contaminated with Staphylococcus epidermidis in 15 patients. All of the contaminated leads have remained clinically uninfected during follow-up. One clean lead became infected early after implantation and the patient died after an open cardiac operation to remove that lead and an adjacent abandoned lead that was adherent to the subclavian vein. No other patient has had a late complication during follow-up to 256 months (mean 47.6). Properly managed abandonment of an uninfected lead can carry a very low complication rate.     

Neuropeptide Y-like immunoreactivity in neurons of the human retina

The distribution of neuropeptide Y-like immunoreactivity (NPY-LI) was investigated in wholemounts and in transverse sections of the human retina. NPY-LI was localized to the soma and axonal processes of large ganglion cells (GCs) and to the soma and dendritic arborization of amacrine cells (ACs). NPY-LI GCs were unevenly distributed across the retina, the highest density of 875 cells/mm2 was found in the fovea centralis and the lowest density of 15 cells/mm2 in the peripheral retina. The total number of NPY-LI GCs in the retina was estimated to be about 85,000. The soma sizes of NPY-LI GCs increased from 116 microns 2 +/- 23 (s.d.) in the retinal centre to 251 microns 2 +/- 57 in the retinal periphery. The soma size of NPY-LI ACs was in the range of 40 and 50 microns 2. In transverse sections NPY-LI was seen to be localized to the optic fibre layer, to the somata of GCs, to the scleral sublamina of the inner plexiform layer (AC dendrites) and to the innermost part of the inner nuclear layer (somata of ACs). The gradients of soma sizes and retinal distribution of NPY-LI GCs were taken as an indication that they correspond to the class of large to very large GCs, previously identified in the human retina by Golgi impregnation.     

Cardiocirculatory disturbances after surgery of carcinoma of the thoracic esophagus

From 1976 to 1985, 277 cases of carcinoma of the esophagus were resected in the Second Department of Surgery, Tohoku University School of Medicine. Postoperative cardiocirculatory disturbances occurred in 114 cases (41.2%), arrhythmia being the disturbance most frequently observed (86.8%). Low cardiac output syndrome occurred in 8 cases and myocardial infarction occurred in 3 cases. The majority of the cases were treated successfully, but 5 patients died within one month after operation. Causes of death were as follows: myocardial infarction, constrictive pericarditis, cardiac tamponade, non-occlusive mesenteric ischemia and acute cardiac failure. Postoperative arrhythmia occurred mainly up to the third postoperative day. Low cardiac output syndrome occurred just after operation or on the first postoperative day. All cases of myocardial infarction occurred on the first postoperative day. The rate of occurrence of cardiocirculatory disturbances in aged patients (greater than or equal to 70) was significantly higher than other group (less than or equal to 69), (56.7%:38.1%, p less than 0.05). The rate of occurrence of cardiocirculatory disturbances in patients who had a history of hypertension or in patients with abnormal preoperative electrocardiographic findings were relatively higher than those in patients who had no history of hypertension or in patients with no abnormal preoperative electrocardiographic findings. The rate of occurrence of cardiocirculatory disturbances in patients who had undergone total resection of the thoracic esophagus was significantly higher than that in patients who had undergone partial resection of the thoracic esophagus (42.8%:23.8%, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Continuous positive airway pressure in the treatment of postoperative hypoxia

The physiopathology of postoperative hypoxia has been analysed, the cause being identified in the worsening of the V/Q ratio consequent on the reduction in CFR. By increasing CFR, CPAP reduces the superimposition of Tidal Volume and Closing Volume, thus reducing dysventilated zones and thereby improving the V/Q ratio and oxyaemia. With these premises, 18 patients undergoing cholecystectomy were examined; 8 of them were treated in the postoperative period with CPAP at pre-established intervals. The results confirm its effectiveness in terms of PaO2 improvement and the need for constant administration, considering that the benefits are lost when the patient is disconnected from the mask.     

HTLV-1 and tropical spastic paraparesis. 1. Clinical features, pathology and epidemiology

The clinical profile of tropical spastic paraparesis (TSP), described in scattered tropical and subtropical territories over the past 30 years, has been more clearly defined since the discovery of its direct association with human T lymphotropic virus type 1 (HTLV-1). A chronic disease of adults, commoner in women, it usually presents as a progressive spastic paraparesis with sphincter disturbance, sometimes with backache and lower limb sensory disorder. Most cases are chair-bound within 10 years. Histology reveals a chronic lymphocytic meningomyelopathy, predominantly in the spinal cord, together with long tract demyelination and hyalinoid thickening of the media and adventitia of small blood vessels. Geographical areas of high prevalence of TSP are known in the Caribbean, South America, South Africa, southern Japan, the Seychelles and probably in India, and it is sparsely endemic elsewhere. The virus appears to exist within lymphocytes for long periods. Vertical transmission occurs postnatally, and sexual and transfusion infection are also recognized, but much remains to be clarified regarding its pathogenesis and epidemiology.