Biomedical subjects
Publications and source records attributed to J Allt-Graham.
This paper describes a method of tracheostomy using a percutaneous dilatational technique. The authors report their experience of 50 elective cases and discuss the technique as an alternative to formal surgical tracheostomy. They suggest that the lower complication rate associated with the percutaneous dilatational method makes feasible its extended use in elective head and neck surgery.
Explore the source record for details and available documents.
We report our experience of using the Pall BB50T heat and moisture exchanging filter (HMEF) in critically ill patients undergoing long-term ventilation. Three hundred and sixty-four ventilated patients humidified with the Pall HMEF were studied prospectively. Thirty-five patients (mean APACHE II score 24.6, mean predicted mortality 50.9%) were ventilated for more than 10 days (mean 18.9), accounting for 661 patient-ventilated days. During this period two patients suffered tracheal tube occlusion. No other complications could be attributed to the filter. We conclude that the Pall BB50T heat and moisture exchanging filter is safe in patients undergoing long-term ventilation. However, its use demands a high degree of respiratory care.
The anti-cardiolipin antibody syndrome (or anti-phospholipid antibody syndrome) is characterized by the presence of autoantibodies to phospholipids. Its major association is with systemic lupus erythematosus. It is characterized further by in vitro prolongation of phospholipid-dependent coagulation tests. However, in vivo it is associated with a markedly increased incidence of thrombosis, both arterial and venous. We describe the case of a 36-yr-old female patient with the anti-cardiolipin antibody syndrome who presented initially for diagnostic laparoscopy and later for exploratory laparotomy. Her postoperative course after the first general anaesthetic was complicated by disseminated intravascular coagulation and adult respiratory distress syndrome. After the second operation, she deteriorated further with worsening cardiac, renal and respiratory function and eventually died. As far as we are aware, this is the first reported case of the anti-cardiolipin antibody syndrome in anaesthetic literature. Further aspects of this puzzling condition and its anaesthetic implications are discussed.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Heat and Moisture Exchangers are used increasingly as filters to prevent the contamination of breathing apparatus and to limit cross-infection. A series of laboratory tests has been developed to evaluate the microbial filtration and air flow resistance properties of these devices. The tests were designed to simulate the clinical situation and therefore evaluated devices in both dry and wet conditions. The devices tested (Engstrom Edith, Pall BB50T, Dar Hygrobac, Intersurgical Filtatherm and Intersurgical Filtaguard) were each representative of a particular type of construction. The simple hygroscopic device (Engstrom Edith) showed poor airborne and liquid-borne filtration efficiency, but its resistance to air flow remained low in all conditions. The composite devices (Dar Hygrobac, Intersurgical Filtatherm and Intersurgical Filtaguard), which all possessed relatively large pores, performed well in terms of dry airborne filtration efficiency, but showed substantial increases in air flow resistance and poor filtration efficiency in the presence of liquid. The pleated membrane filter (Pall BB50T), which possessed small pores, showed good airborne filtration efficiency and prevented the passage of liquid. The latter property enabled this device to prevent the passage of liquid-borne contamination and to maintain a low resistance to air flow in wet conditions. It would appear that in terms of contamination control and air flow resistance the pleated membrane filter provides a wider margin of safety than either the hygroscopic or composite devices.
Twenty-eight patients who required periods of mechanical ventilation for up to 22 days in the intensive therapy unit were studied to evaluate the clinical use of the Pall Ultipor Breathing System Filter (BB50T) as a heat- and moisture-exchanging bacterial filter. Results in this group of patients showed that there was no longer any need to sterilise breathing systems or decontaminate ventilators if these filters were used. They also performed satisfactorily as a heat and moisture exchanger in patients in need of long-term ventilation, and their use appears to offer substantial advantages as regards cost, ease of use and patient safety.
Explore the source record for details and available documents.
The prophylactic use of intravenous lignocaine 1.5 mg/kg given 1 minute prior to induction of anaesthesia has been shown to reduce significantly the incidence of dysrhythmias during dental anaesthesia, and reduce the rise in blood pressure associated with tracheal intubation.
The Cape Bristol ventilator is a volume-preset machine which utilises oxygen from a flowmeter and air-entrainment attachment to provide a known inspired oxygen level. The level can be calculated from the oxygen flow rate and the patient's minute ventilation using a nomogram supplied by the manufacturers. Serious discrepancies between predicted and measured inspired oxygen levels delivered by these machines can occur and the advisability of using air entrainment devices in high oxygen dependent patients is questioned. Modification to the Cape Bristol ventilator to limit these errors are discussed and the more frequent use of oxygen monitors recommended.
Explore the source record for details and available documents.