Premedication with clonidine before TIVA optimizes surgical field visualization and shortens duration of endoscopic sinus surgery - results of a clinical trial

BACKGROUND

During functional endoscopic sinus surgery (FESS), intraoperative bleeding can significantly compromise visualization of the surgical field. Clonidine constricts peripheral blood vessels and reduces systemic blood pressure, which in combination decrease nasal mucosa blood flow. This dual effect can potentially reduce bleeding during FESS and stabilize the intraoperative hemodynamic profile of the patient.

AIM

The aim of this prospective study was to assess if the quality of the surgical field visualization during FESS was improved when clonidine was used as a premedication agent.

METHODOLOGY

A group of 44 patients undergoing FESS for chronic sinusitis and polyp removal were enrolled and randomly assigned to receive either oral clonidine or midazolam as preoperative premedication. During the operation, the quality of the surgical field was assessed and graded by the operating surgeon using the scale proposed by Boezaart. The evaluations were done during surgery at 15 minutes (K1), 30 minutes (K2), 60 minutes (K3) and 120 minutes (K4) after incision.

RESULTS

The duration of the surgical procedure was significantly shorter in the clonidine group: mean time of surgery: 80 vs. 96 min in the clonidine and midazolam groups, respectively. Also better quality of surgical field was observed at all time points in the clonidine group.

CONCLUSION

Premedication with clonidine before FESS results in shortening of the surgical time and a better quality of the surgical field.

Liver transplantation outcome in patients with angiographically proven coronary artery disease: a multi-institutional study

Over the last decade the age of liver transplant (LT) recipients and the likelihood of coronary artery disease (CAD) in this population have increased. There are no multicenter studies that have examined the impact of CAD on LT outcomes. In this historical cohort study, we identified adult LT recipients who underwent angiography prior to transplantation at seven institutions over a 12-year period. For each patient we recorded demographic data, recipient and donor risk factors, duration of follow-up, the presence of angiographically proven obstructive CAD (≥50% stenosis) and post-LT survival. Obstructive CAD was present in 151 of 630 patients, the CAD(+) group. Nonobstructive CAD was found in 479 patients, the CAD(-) group. Patient survival was similar for the CAD(+) group (adjusted HR 1.13, CI = [0.79, 1.62], p = 0.493) compared to the CAD(-) group. The CAD(+) patients were further stratified into severe (CADsev, >70% stenosis, n = 96), and moderate CAD (CADmod, 50-70% stenosis, n = 55) groups. Survival for the CADsev (adjusted HR = 1.26, CI = [0.83, 1.91], p = 0.277) and CADmod (adjusted HR = 0.93, CI = [0.52, 1.66], p = 0.797) groups were similar to the CAD(-) group. We conclude that when current CAD treatment strategies are employed prior to transplant, post-LT survival is not significantly different between patients with and without obstructive CAD.

Association between preoperative statin therapy and postoperative change in glomerular filtration rate in endovascular aortic surgery

BACKGROUND

Acute kidney injury during endovascular aortic repair can result in a reduction in the postoperative glomerular filtration rate (GFR). The 'pleiotropic' effects of statins offer a potential mechanism of reducing the postoperative decline in the GFR. We therefore tested the hypothesis that in patients undergoing endovascular aortic repair, the GFR decreases less in patients taking preoperative statins than in those who do not.

METHODS

A cohort investigation of 501 consecutive patients who underwent endovascular aortic repair between June 2005 and March 2007 in an academic tertiary care centre. Multivariable linear regression was used to assess the association between the statin use and the postoperative GFR, after adjusting for the baseline GFR and other confounding covariables selected using a stepwise criterion.

RESULTS

The statin use was not associated with a change in the postoperative GFR (P=0.94); the difference (95% confidence interval) in the mean postoperative GFR (statins minus no statins) was estimated at 0.1 (-3.1, +3.4) ml min(-1) 1.73 m(-2). A decrease in the GFR of ≥ 25% (the threshold to diagnose contrast-induced nephropathy) developed in 26 of 192 patients given statins before operation (13.5%) compared with 36 of 296 patients who were not taking statins (12.2%).

CONCLUSIONS

Statin therapy is not associated with a statistically significant change in the mean postoperative GFR in patients undergoing endovascular aortic surgery, nor a reduction in the risk of a GFR decline of >25%.

Central venous pressure during the post-anhepatic phase is not associated with early postoperative outcomes following orthotopic liver transplantation

BACKGROUND

Fluid management during orthotopic liver transplantation poses unique challenges for the anesthesiologist. Maintenance of hypovolemia as indicated by low central venous pressure has been associated with reduced blood loss and improved outcomes in some studies, but with higher 30-day mortality and increased incidence of renal dysfunction in others. The primary aim was to evaluate the association of central venous pressure management after liver allograft reperfusion with immediate postoperative patient outcomes.

METHODS

This was a retrospective investigation evaluating the intraoperative and postoperative records of 144 consecutive patients who underwent orthotopic liver transplantation at a single institution.

RESULTS

We did not find any important association between central venous pressure management after graft reperfusion and postoperative patient outcomes. Specifically, these data do not support the hypothesis that maintenance of lower central venous pressure during the post-anhepatic phase of orthotopic liver transplantation is associated with improved immediate postoperative allograft function (except for a steeper decrease in post operative days 1-3 in 2 of the 3 liver function test: alanine aminotransferase and bilirubin) or overall patient survival, graft survival, composite graft/patient survival, intensive care length of stay, hospital length of stay or the occurrence of infections.

CONCLUSION

Maintaining a lower central venous pressure during the post-anhepatic phase during orthotopic liver transplantation is not associated with any benefit in terms of immediate postoperative allograft function, graft survival or patient survival.

Anesthetic management for emergency cesarean section in a patient with severe valvular disease and preeclampsia

Wider selection of young patients for prosthetic valve replacement for valvular heart disease has resulted in an increase in number of women with heart disease reaching childbearing age. Such patients presenting in labor for emergency cesarean section require special consideration. We present a report of a parturient who presented at 36 weeks of gestation with severe aortic and mitral stenosis, pulmonary edema and severe preeclampsia. The goals of our anesthetic management included (1) careful airway management (2) maintaining stable hemodynamics (3) optimizing fluid status, and (4) preventing seizures. Issues related to management of patients with severe valvular disease, prosthetic valves and complications due to anticoagulant therapy during pregnancy are discussed.