Search

Nine patients with acute superimposed on chronic respiratory failure presented with severe bilateral chemosis and conjunctival venous engorgement All patients manifested florid right heart failure and hypoxemia while seven also had evidence of left ventricular failure and eight experienced hypercapnia. As the heart failure and arterial blood gases improved, the above mentioned ocular manifestations slowly cleared. Chemosis and conjunctival venular engorgement may be a little appreciated sign of combined cardiopulmonary failure.

The output of water from conventional and experimental humidification devices was determined under conditions similar to those encountered by a patient who is intubated and spontaneously breathing. Absolute humidity was measured by a modified dewpoint hygrometer, and relative humidity at 37°C was then calculated. Only two of the unheated pneumatic nebulizers tested were capable of delivering near 100 percent relative humidity at 37°C, while both ultrasonic nebulizers tested were able (at maximum outputs) to more than double this humidity content. An external heat source was necessary to increase the water content of gases delivered from pure humidifiers (no particulate water output) to above 50 percent relative humidity at 37°C. No correlation could be made between visible fog and actual water content in the humidified gases. Frequent changes in control were necessary to maintain a constant output when the heated humidifier was run continuously for a six-hour period, while prolonged warm-up periods were necessary prior to achieving stable outputs when the ultrasonics were so tested. The most efficient unheated pneumatics, however, maintained a stable and satisfactory output throughout the six-hour test period. It was concluded that the newer pneumatically driven, unheated nebulizers are capable of delivering gases with nearly 100 percent relative humidity at 37°C, therefore eliminating the need for heated or ultrasonically driven nebulizers for routine clinical use.

Seven groups of rats were trained in a passive avoidance task. All groups were tested 24 hr later to assure retention of the task. One group of animals was then administered an ECS treatment. Three groups were administered an ECS treatment under conditions which eliminate or reduce the production of hypoxia. Another group was exposed to a nitrogen atmosphere to induce hypoxia by a different method. All groups were then retested for retention of the passive avoidance task 3 and 24 hr later. The results indicate that ECS or nitrogen inhalation (both hypoxia producing treatments) produce an amnesia for the passive avoidance task at the 3 hr retest but not at the 24 hr retest. In contrast, minimizing or eliminating the hypoxic consequences of an ECS treatment does not result in a temporary amnesic effect.

Apneic oxygenation was studied in 13 patients undergoing Jako-Laryngoscopy with a pharyngeal catheter fur oxygen administration and 18 patients having minor surgical procedures with a cuffed endotracheal lube in place for oxygen administration. Arterial Poz,Pcoz, and pH, functional residual capacity

Lecerof, H. (1974). Thorax , 29 , 673-677. Central haemodynamics during oxygen breathing in angina pectoris. The haemodynamic effects of breathing 100% oxygen have been studied by right heart catheterization at rest and during bicycle exercise in nine male patients with coronary heart disease. Oxygen breathing produced no significant haemodynamic benefit during angina pectoris induced by physical exercise, although at rest a reduction in heart rate and cardiac index was evident. The favourable effects of 100% oxygen breathing described in pacing-induced angina pectoris cannot therefore be transferred to exercise-induced angina probably because the myocardial blood flow during the latter condition is hampered by an increased left ventricular end-diastolic pressure.

SummaryChanges in contractility indices for left ventricular muscle were calculated during air and oxygen breathing in 19 studies on 14 patients with coronary artery disease. The following significant changes were observed on oxygen breathing: rises in pO2 of arterial blood, in left ventricular systolic pressure, and in tension-time index, and a fall in the velocity of the shortening of the contractile element of the left ventricular muscle at zero load (Vmax). The fall in Vmax was similar even when heart rate was maintained constant. These observations suggest that oxygen breathing diminishes myocardial contractility and consequently may reduce myocardial oxygen demand. It is recognized that the reduction in myocardial contractility may be only one of the factors responsible for the decrease in myocardial oxygen demand induced by oxygen administration.

Postoperative pulmonary complications are a serious danger to any patient who undergoes surgery. The increase in geriatric surgery has brought into focus certain marginal factors that can spell the difference between success and failure. In a series of 300 elderly patients who underwent major surgery at the Henry Ford Hospital, there were 34 in whom clinical and radiologic evidence of atelectasis developed. In 19 others, x-ray examination of the chest showed various infiltrates suggesting pneumonitis, and sputum cultures grew coliform bacteria. Despite appropriate treatment, 5 patients died from postoperative pulmonary complications. Illustrative cases of hypoventilation, atelectasis, pneumonia and pneumothorax are presented. Recommendations are made for the care of the elderly undergoing major surgery, including the preoperative identification of chronic lung disease, determination of the respiratory reserve, preoperative exercises in deep breathing and coughing for use after operation, adequate oxygenation during the surgical procedure, close supervision of postoperative respiratory ventilation for the first seventy-two hours, selective use of mechanical respiratory assistance, and emphasis on early ambulation.

Šamánek, M., Tůma, S., Benešová, D., Povýšilová, V., Pražský, F., and Čápová, E. (1974).Thorax, 29, 446-450. Atresia of right pulmonary veins and anomalous left pulmonary venous drainage into portal circulation. An anomaly of pulmonary venous drainage in a male newborn infant is described whereby the left pulmonary veins entered the portal vein and the right pulmonary veins were atretic. A correct diagnosis was made by detecting high-oxygen saturation in the hepatic veins, right-to-left shunt at atrial level, and increased pulmonary artery wedge pressure in comparison with the left atrial pressure, and was confirmed by angiography.

The relationship of surfactant deficiency, immaturity, and intrapartum complications to the arterial oxygen tension (Pa O 2 ) while breathing 100 per cent oxygen (hyperoxia test) was studied in 88 preterm infants, who were the products of 80 highrisk pregnancies. The hyperoxia test was performed from one to six hours of life. The Pa O 2 was significantly related to the foam stability test (FST) if there was no RDS and the 5 minute Apgar score was ≥6. A low Pa O 2 was significantly related to a history of intrapartum complications and a 5 minute Apgar score ≤5, but not to the FST. A hyperoxia test value greater than 200 mm. Hg was not associated with any deaths from RDS nor with the need of mechanically assisted ventilation. All of the 21 deaths were associated with history of intrapartum complications. A Pa O 2 ≤200 mm. Hg defines the high-risk group for RDS. The highest predictability of deaths from RDS (85 per cent) was further defined by the combination of factors: Pa O 2 ≤200 mm. Hg, intrapartum complications, 5 minute Apgar score ≤5, and arterial pH≤7.20.

Summary In a prospective study of 18 trauma cases we found that the fat embolism syndrome developed in eight (according to biochemical evidence), although only three of these patients showed clinical symptoms. Biochemical signs of fat embolism include disturbances in the clotting factors; fat excretion; changes in fat metabolism, and hypoxemia. The presence of any of these signs should alert the surgeon to the possibility of fat embolism and we recommend routine screening of all severely traumatized patients by hematologic tests, lipids investigation, blood gas measurements, as well as roentgenographic examination.

Smith, P. and Heath, D. (1974).Thorax, 29, 643-653. Paraquat lung: a reappraisal. The histopathology of the lungs from four human cases of paraquat poisoning is described. In two of them there was a dense mass of fibroblastic tissue which obliterated the lung architecture, and one of these showed an extensive deposit of collagen with honeycomb change. In a third case pulmonary fibrosis was less severe and could be demonstrated exclusively within the alveolar spaces. The fourth showed earlier lesions of capillary congestion, alveolar oedema, and hyaline membrane formation. We suggest that paraquat produces the same effect on the lung in man as in the rat, namely a diffuse, cellular, intra-alveolar fibrosis. The intra-alveolar origin of this fibrosis is often obscured in the advanced stage of the disease and has been misinterpreted as fibrosing alveolitis. This fibrosis is associated with a pulmonary vascular disease. In assessing the histopathology of the lung in paraquat poisoning a history of oxygen therapy must be taken into account, for prolonged exposure to this gas may in itself induce pulmonary fibrosis.

The relative importance of centrally mediated reflex responses versus the release of circulating humoral substances in the heart's response to acute hypoxia was studied in the transplanted human heart with its residual innervated recipient atrium and denervated donor atrium. The sinus node rates of both the donor and recipient atria were compared by monitoring P wave activity on the standard electrocardiogram in six patients during control and hypoxic conditions. Breathing 13 per cent oxygen for 10 minutes resulted in an average oxygen saturation of 75 per cent and an oxygen tension (pO 2 ) of 40 mm Hg, and was associated with a 16 per cent (p 0.05) increase in the recipient sinus node rate, but with no change in the donor sinus node rate. Pretreatment with atropine abolishes this increase in the innervated recipient sinus node. Breathing 10 per cent oxygen resulted in an oxygen saturation of 55 per cent and a pO 2 of 25 mm Hg, with an associated 10 per cent increase in both donor and recipient sinus node rate. These studies indicate that changes in heart rate during mild degrees of hypoxemia are mediated by a central reflex mechanism which leads to the release of normal vagal parasympathetic tone. The increase in heart rate that occurs in both the innervated and denervated sinus node rates during more severe degrees of hypoxia is probably due to the release of circulating humoral substances, since reinnervation has not been documented in the human cardiac allograft.

The effects of six different modes of therapy on arterial pH, pCO2 pO2 and pulmonary function tests were measured in 18 patients with asthma. No uniformly predictable outcome was observed with any of the treatment programs. Improved values were best sustained with epinephrine and aminophyll

Comparison in 13 newborns between aortic and digital arteriolar oxygen tension on 40 occasions revealed no correlation. The digital arteriolar oxygen tension is not a realable guide to oxygen therapy in the newborn.

One brisk Sunday morning, three teaching sisters of the Third Order of St. Francis were exploring the sea cliffs on an isolated beach on the south shore of Maui. It was a high-surf day and waves charged into the pali in a spectacular show of spray and sound. The youngest, more adventurous sister, a 29-year-old teacher, scrambled down the rocky surface to a vantage point about six feet above the sea. Suddenly a giant wave swept in, engulfed her, and carried her out into the rough water of the cove.... Language: en

Hoflin, F. & van der Linden, W. Pneumatosis cystoides intestinalis treated by oxygen breathing. Scand. J. Gastroent. 1974, 9, 427-430.The histories are given of two patients with pneumatosis cystoi...

Flexible fiberoptic endoscopy of the respiratory tract is a relatively new technique. It is essential that endoscopists and head and neck surgeons develop facility with this instrument. The technique of transnasal flexible laryngobronchoscopy is described. Unique applications are illustrated. Diagnostic and therapeutic uses include differentiation of benign from malignant neoplasms, diagnosis of respiratory inflammatory disease and facilitation in endotracheal intubation.

Crew, A. D., Varkonyi, P. I., Gardner, L. G., Robinson, Q. L. A., Wall, E., and Deverall, P. B. (1974). Thorax , 29 , 437-445. Continuous positive airway pressure breathing in the postoperative management of the cardiac infant. Continuous positive airway pressure with spontaneous ventilation was used in the postoperative period following palliative or corrective surgery for congenital heart defects in a group of children of less than 3 years of age. After stabilization of the cardiovascular state, continuous positive airway pressure breathing (CPAP) was shown to be a suitable alternative to continuous positive pressure ventilation (CPPV). A statistically significant increase in PaO2 was observed on changing from CPPV to CPAP. A statistically significant decrease in PaO2 and increase in pulmonary venous admixture was observed after discontinuing the positive airway pressure and allowing the patient to breathe at ambient pressure. We would recommend CPAP as an intermediate manoeuvre in the withdrawal of ventilatory support as it introduces a smoothness and stability into patient management regimes which was previously lacking. Careful selection of apparatus is necessary as the airway pressure should be truly continuous and steady. In neonates the dead space of the system should be reduced to a minimum; CPAP alternating with periods on CPPV may be necessary for some time after cardiovascular stability has been attained.

Heparin remains the therapeutic agent of choice. Investigations of platelet inhibiting agents, prothrombinopenic agents, fibrinolytic agents, and defibrinogenating agents have failed to show the superiority of any of these substances over heparin, although fibrinolytic agents may be more beneficial in the patient with massive pulmonary embolism and cardiopulmonary decompensation.

One hundred thirty-three children, with birth weights of 1,500 Gm. or less, were examined at approximtaely 10 years of age in order to evaluate their outcome in relation to postnatal nursery routines. Following curtailment of oxygen administration, there was a decrease in severe retrolental fibroplasia, but not in cicatricial stages I through III. There was a lower mortality rate during the period of low oxygen administration. However, factors other than oxygen were likely responsible for the improved outcome, since the data were gathered in a sequential manner and included advancements in medical and nursing care. The high incidence of neurosensory hearing losses was examined in relation to administration of ototoxic drugs during the neonatal period. Evidence for a relationship between streptomycin therapy and hearing loss was obscured by the frequency of other central nervous system disease and hypoxic episodes during the neonatal period. Data on feeding practices and later I.Q. revealed a remarkably low caloric intake during the first week after birth in nearly all of the children studied. It can be reasoned that the postnatal feeding routine was crucial in the poor outcome of the children reported herein, but the importance of these data will become clear only when children who have received adequate intakes are evaluated.