Pulse oximeters are being widely used for non-invasive, simultaneous assessment of haemoglobin oxygen saturation. They are reliable, accurate, relatively inexpensive and portable. Pulse oximeters are often used for estimating heart rate at rest and during exercise. However, at present the data available to validate their use as heart rate monitors are not sufficient. We evaluated the accuracy of two oximeters (Radiometer, ear and finger probe; Ohmeda 3700, ear probe) in monitoring heart rate during incremental exercise by comparing the pulse oximeters with simultaneous ECG readings. Data Toward the end of each stage, during the last 15 s, simultaneous measurements of heart rate were made with direct ECG (Hewlett Packard 1500B, 12-lead, Rockville, Maryland, USA) tracings and readings from the LCD digital displays of the oximeter. Heart rate before the test, at rest and at warm-down (cycle lkg load, 70r.p.m.; treadmill 0°, 1.7m.p.h.) were also recorded at three consecutive 2-min intervals. Finger and ear lobes were cleaned with 70% isopropyl alcohol before placing the probes. To minimize motion artefacts, the wiring of ear probes was secured with a head band and the finger probe was taped on the right index finger. Stability of the probes was tested by asking the subjects to move their heads and fingers before the tests started.Data analysis Linear regression analysis was used to determine the predictive capacities of pulse oximeters in estimating heart rate at rest and during exercise. Differences between mean heart rate recorded by oximeters and by ECG were analysed by a paired Mtest (two-tail

Although effective in maintaining relatively normal levels of blood pressure in hypertensive patients and retarding some of the serious and fatal secondary consequences of the disease, hexamethonium ion and 1-hydrazinophthalazine can cause severe immediate and late reactions. The latter drug has produced collagen diseases of varying degrees of severity, all of which have regressed on cessation of medication, in 14 of 253 patients. The combination has given rise to fatal interstitial pneumonia in 5 of 89 in malignant stages of hypertension. Less serious side effects of each agent are also discussed.

This report is the first of a series on a method for treatment of hypertension by oral hexamethonium chloride and hydrazinophthalazine.

Patients undergoing extracorporeal membrane oxygenation (ECMO) are at an increased risk for developing coagulopathies due to the adverse effects of extracorporeal circulation on the hemostatic mechanism. Methods of determining causative factors of bleeding diathesis are often inconsistent and non-specific. ECMO patients require aggressive transfusion therapy with autogenic blood products to stabilize and maintain hemostasis. The present study evaluated the coagulation status of newborn patients undergoing ECMO therapy, using a viscoelastic monitor (Thrombelastograph -TEG) that measures functional aspects of clot development and stabilization. Seventeen neonatal patients undergoing ECMO for severe respiratory dysfunction were entered into this study. Serial blood samples were obtained and routine coagulation assessment including fibrinogen concentration, platelet count and ionized calcium was performed. In addition, fibrin ( ogen) degradation products (FDP), d-Dimers, antithrombin III and plasma free hemoglobin were measured. Transfusion indicators were established and total transfusion requirements recorded. TEG profiles were determined with the use of heparinase, an enzyme that degrades heparin but has little effect on other coagulation factors. The most commonly encountered complication was hemorrhaging which was diagnosed by laboratory and clinical assessment in 11 of 17 patients. Transfusion requirements (measured in ml/kg/ECMO hour) were the following: packed red blood cells - 1.34±0.5; platelets - 0.71 ±o.57; fresh frozen plasma- 0.09±0.12; cryoprecipitate 0.05 ±o.05. Thrombelastograph profiles reflected hemostatic conditions that ranged from severe coagulopathies (DIC) to hypercoagulability. Interpretation of TEG profiles identified hemostatic abnormalities in 57 of 101 profiles ( 46.5% ), with the most common etiology related to platelet dysfunction. In the non-hemorrhagic group the TEG profiles were normal in 30 of 41 (73.2%) instances, while the hemorrhagic group had 24 of60 (40%) profiles in the normal range (p<.001). d-Dimers and FDP were elevated in all patients during ECMO despite maintenance of activated clotting times greater than 180 seconds. During ECMO coagulation assessment with the TEG provides useful information for the rapid diagnosis of hemorrhagic conditions, which may help guide transfusion therapy.

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