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G Haddow

Publications and source records attributed to G Haddow.

7 recordsLinked to original sources

"Because you're worth it?" The taking and selling of transplantable organs.

In the UK, the legal processes underpinning the procurement system for cadaveric organs for transplantation and research after death are under review. The review originated after media reports of hospitals, such as Alder Hey and Bristol, retaining organs after death without the full, informed consent of relatives. The organ procurement systems for research and transplantation are separate and distinct, but given that legal change will be applicable to both, some have argued now is the time to introduce alternative organ transplant procurement systems such as presumed consent or incentive based schemes (despite inconclusive British and American research on the status of public attitudes). Findings are reported in this paper from qualitative and quantitative research undertaken in Scotland in order to ascertain the public acceptability of different procurement systems. Nineteen in depth interviews carried out with donor families about their experiences of donating the organs of the deceased covered their views of organ retention, presumed consent, and financial incentives. This led onto a representative interview survey of 1009 members of the Scottish public. The originality of the triangulated qualitative and quantitative study offers exploration of alternative organ procurement systems from different "sides of the fence". The findings suggest that the legal changes taking place are appropriate in clarifying the role of the family but can go further in strengthening the choice of the individual to donate.

Adolescent↗

A multicenter evaluation of a new continuous cardiac output pulmonary artery catheter system.

OBJECTIVE: To validate a new system of continuous cardiac output monitoring. DESIGN: Multicenter, prospective, nonrandomized clinical study. SETTING: Four university hospitals. PATIENTS: Forty-seven adult intensive care unit patients. INTERVENTIONS: Pulmonary artery catheterization. MEASUREMENTS AND MAIN RESULTS: Continuous and bolus cardiac output measurements were obtained over 72 hrs. The 327 continuous cardiac output measurements compared favorably with bolus cardiac output measurements (bias = 0.12 L/min, precision = +/-0.84). The continuous cardiac measurement was not adversely affected by temperatures of <37 degrees C or >38 degrees C, high (>7.5 L/min) or low (<4.5 L/min) cardiac output values, or duration (72 hrs) of the study. CONCLUSIONS: This continuous cardiac output system provides a reliable estimate of cardiac output for clinical use if applied in conditions similar to this study. The combination of a continuous measure of cardiac output with other continuous physiologic monitoring (arterial and mixed venous oxygen saturation, oxygen consumption, etc.) may provide important information that no single parameter could achieve.

Adolescent↗

Volume-mediated pulmonary responses in liver transplant candidates.

Pulmonary hypertension, defined as mean pulmonary artery pressure (mPAP) greater than or equal to 25 mmHg, is a recognized complication of hepatic dysfunction with portal hypertension and is considered a relative contraindication to liver transplantation. To characterize pulmonary hemodynamic responses in OLT candidates without pre-existing primary pulmonary hypertension, 22 consecutive patients referred for OLT at the Stanford University Hospital underwent prospective right heart catheterization with pressure determinations at baseline and following infusion of 11 crystalloid over 10 min. In addition, EKG, chest X-ray and transthoracic echocardiograms were performed as a part of the routine evaluation. Eleven non-cirrhotic patients served as controls. At baseline, 1/22 (4.5%) OLT patients had pulmonary hypertension while 9/22 (41%) developed pulmonary hypertension following volume infusion (p < 0.0001). In contrast, 0/11 controls manifested elevated pulmonary pressures at baseline or following volume challenge. OLT candidates were found to have significant increases in mean pulmonary pressure and capillary wedge pressure (PCWP) compared to controls, suggesting intravascular volume overload or left ventricular dysfunction as potential causes. OLT candidates who manifested volume-dependent pulmonary hypertension (a) had a 2-fold higher baseline PCWP, (b) currently smoked, and (c) had previously undergone portosystemic shunts. Aggregate analysis of EKG, echo and CXR for determination of volume-mediated pulmonary hypertension revealed a sensitivity of 25%, specificity of 75% and a positive predictive value of 40%. Preoperative identification of patients with a predisposition to manifesting elevated pulmonary pressures in the context of rapid volume infusion offers the potential for improved risk stratification and optimized clinical management.

Adult↗

Orthotopic liver transplantation with selective use of venovenous bypass.

BACKGROUND: To determine the utility of selective use of venovenous bypass (VVB), an algorithm based upon hemodynamic criteria was instituted at Stanford University Medical Center: the bypass was used if the systolic blood pressure decreased below 100 mm Hg with a trial of caval and portal clamping. PATIENTS AND METHODS: Eleven consecutive patients underwent orthotopic liver transplantation (OLT) with use of VVB on a selective basis; using the hemodynamic exclusion criteria, none required VVB. A group of 20 patients undergoing OLT with VVB served as historical controls. RESULTS: Overall patient and graft survival were identical in both groups (75%). Avoidance of VVB decreased operative and warm ischemia time and decreased peak transaminase and total bilirubin values, but increased rates of intraoperative blood loss. However, the absolute numbers of blood products administered were not different between groups. CONCLUSION: Selective use of VVB for OLT does not incur increased morbidity or mortality. Potential advantages include cost savings with decreased operative and anesthetic time.

Adult↗

Systemic venous flow during cardiac surgery examined by intraoperative transesophageal echocardiography.

Patterns of systemic venous return change after cardiac surgery. However, the exact timing and underlying mechanisms are not well understood. To analyze these changes transesophageal echocardiography was used to evaluate 21 patients (mean age 56 +/- 17 years) during cardiac surgery. Eleven patients underwent coronary bypass grafting, 2 had ablation of accessory bundles, 4 had mitral and 4 had aortic valve replacements. All were in sinus rhythm and were undergoing their first cardiac operation. Hepatic and pulmonary venous flow, tricuspid annular motion, and signs of tricuspid regurgitation were recorded sequentially 5 times: (A) with chest closed, (B) with chest open and pericardium closed, (C) with both chest and pericardium open, (D) after cardiopulmonary bypass with chest open, and (E) after cardiopulmonary bypass with chest closed. The hepatic venous Doppler flow velocity integrals (cm) changed, from stage A to stage E: systolic flow decreased from 5.9 +/- 5.2 to 2.2 +/- 1.4 (p less than 0.01); diastolic flow increased from 3.1 +/- 1.5 to 4.8 +/- 3.3 (p less than 0.001); and systolic to diastolic ratio decreased from 2.0 +/- 1.2 to 0.7 +/- 0.6 (p less than 0.001). Reversed flow at the end of ventricular systole was present in 9 patients (43%) at stage A and in all patients at stage E. Decreased tricuspid annular motion was noted in all but 1 patient after cardiopulmonary bypass. No patient presented significant tricuspid regurgitation at any stage. In conclusion, the significant change in the pattern of systemic venous return after open heart surgery is not due to opening of the chest wall or parietal pericardium, or to tricuspid regurgitation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗