Biomedical subjects

D E Cameron

Publications and source records attributed to D E Cameron.

At least 91 records · Page 5Linked to original sources

PubMed1987

A no-flush, core-cooling technique for successful cardiopulmonary preservation in heart-lung transplantation.

In order to determine whether a no-flush, core-cooling technique could provide extended heart-lung preservation, we placed donor calves on cardiopulmonary bypass and instituted rapid cooling to 15 degrees C during the continuous infusion of isoproterenol. The heart and lungs were harvested after the administration of a cardioplegic solution through the aortic root. In the control group (N = 5), heart and lungs were orthotopically allotransplanted immediately. In the preserved group (N = 5), heart and lungs were similarly excised but were stored in a normal saline bath at 4 degrees C for approximately 4 hours and then transplanted. Both groups received isoproterenol during reperfusion and were studied for 6 hours after implantation. A load independent analysis of myocardial function was done by determining with a sonomicrometer the ratio of the end-systolic pressure to the end-systolic dimension. Pulmonary preservation was evaluated by measurement of extravascular lung water with a double-indicator dilution method, arterial oxygenation on 100% inspired oxygen, and serial lung biopsies. Myocardial and pulmonary function after 4 hours of static preservation was found to be similar to controls. No-flush, core-cooling with cardiopulmonary bypass provides adequate cardiorespiratory function after acute bovine heart-lung allotransplantation. With the use of this technique, successful extended cold ischemic cardiopulmonary preservation for heart-lung transplantation may be achieved.

Animals↗

PubMed1986

Surgical treatment of aneurysms of the ascending aorta in the Marfan syndrome. Results of composite-graft repair in 50 patients.

The life expectancy of patients with the Marfan syndrome is reduced by complications caused by dilatation of the ascending aorta. Because surgical therapy with a composite graft may alter this natural history, we analyzed the preoperative and long-term postoperative status of 50 consecutive patients who received such a graft. At surgery, the patients had a mean age of 32.2 years and a mean aortic diameter of 7.1 cm (range, 5.3 to 10). Dissection of the ascending aorta was present in 14 patients and was acute in 5. None of the 44 patients who underwent elective repair, and only one of the six patients who had emergency surgery, died in the hospital; thus, the overall hospital mortality was 2 percent. Five of the 49 survivors died during a follow-up period of up to eight years (10.2 percent late mortality). During the most recent four years of evaluation of this series (38 patients), no postoperative deaths due to intrathoracic problems occurred. Actuarial survival was 87 percent at both two and five years. Composite-graft repair of the ascending aorta in patients with the Marfan syndrome can be performed with low operative and long-term mortality. Because of the unfavorable natural history of the Marfan syndrome and the potential for dissection in moderately dilated aortic roots, we recommend prophylactic repair when the aneurysm reaches a diameter of 6 cm.

Adolescent↗

PubMed1985

The esophageal obturator airway: obturator or obtundator?

The esophageal obturator airway (EOA) has been approved for use in cardiopulmonary resuscitation (CPR) since 1973. Complications reported with its use include esophageal rupture, aspiration, and inadvertent tracheal occlusion or intubation with the obturator. Five cases of unrecognized tracheal intubation occurring in 170 cases of EOA use during CPR are reported. Records were analyzed for extent and treatment of injuries in the field and the hospital, blood gas levels before and after replacement of the erroneously placed EOA with an endotracheal tube (ETT), and outcome. Blood gas analysis confirmed absent ventilation and profound acidosis following tracheal intubation with the EOA with average EOA arterial blood gases: pH 6.9/pCO2 78/pO2 47. Mortality from this complication was 100%. Tracheal intubation with the EOA is under-recognized and under-reported. It is a potentially lethal complication. The EOA should be replaced with standard bag mask technique or preferably endotracheal intubation in the field by emergency medical technicians.

Adult↗

PubMed1983

Is the undeniably palpable liver ever 'normal'?

A study of whether the lower border of the normal liver, if it extended below the costal margin, could be reliably identified by clinical examination was undertaken in 42 patients in whom there was no clinical, biochemical or scintographic evidence of liver disease. Two clinical observers independently agreed that in 10 of these patients the liver extended infracostally. However, scintiscanning demonstrated that 30 patients had livers extending below the costal margin and that 2 of the 10 livers clinically identified did not in fact lie infracostally. Thus whilst the normal liver commonly extended below the costal margin, recognition of this extension by clinical methods occurred no more frequently than would be expected by chance. It is concluded that the confident clinical finding of a liver projecting below the costal margin should suggest that the organ is abnormal.

Adult↗

PubMed1981

Hepatocellular dysfunction in early sepsis despite increased hepatic blood flow.

Although it is known that hepatic failure occurs in late sepsis, it is not known whether there are alterations in hepatocellular function in early sepsis when hyperdynamic circulation exists in conjunction with hyperglycemia and hyperinsulinemia. To study this, indocyanine green (ICG) clearance and serum levels of hepatic enzymes were measured during early and late sepsis. Sepsis in rats was produced by cecal ligation and puncture (CLP). Ten hours following CLP (early sepsis) total hepatic blood flow (THBF) as measured by hydrogen polarography increased from 23.9 +/- 1.1 to 30.6 +/- 1.4 (ml/min/100 gm). ICG (5 mg/kg body weight--BW) was given intravenously and sequential blood samples taken to determine ICG clearance. ICG half-times (T/2) were 4.99 +/- 0.15 and 6.57 +/- 0.51 minutes for sham-operated and early sepsis rats, respectively (mean +/- S.E., P less than 0.01). SGOT and SGPT levels (IU/ml) increased from 38.1 +/- 0.6 to 69.8 +/- 2.6 and 9.9 +/- 0.4 to 25.6 +/- 1.5, respectively (P less than 0.001). Thus the T/2 of ICG as well as serum levels of liver enzymes increased significantly during early sepsis. Eight additional rats underwent CLP and were tested 16 hours later (late sepsis). THBF in late sepsis decreased to 15.5 +/- 0.5 ml/min/100 gm. ICG T/2 at that time was 8.2 +/- 0.48 min and SGOT and SGPT level were 132 +/- 14.5 and 42 +/- 3.4, respectively (P less than 0.001). These results indicate that heptocellular dysfunction occurs even in the early period of sepsis when THBF is increased. Progressive dysfunction occurs in late sepsis concomitant with a decrease in THBF.

Alanine Transaminase↗

PubMed1968