Haematocrit measurements during cardiopulmonary bypass surgery: comparison of three stat methods with a blood cell counter.

Monitoring packed cell volume (PCV) is essential to safeguard oxygen delivery to the tissues during cardiopulmonary bypass (CPB). We compared the results obtained using a PCV monitor, a blood gas analyser and a microcentrifuge with those from a laboratory-based automated blood cell counter. PCV was measured in 221 samples of 40 patients undergoing open-heart surgery. The limits of agreement (mean difference +/- 2 SD) was unacceptably wide when the results obtained with the PCV monitor and the blood gas analyser were compared with those of the automated blood cell counter. This was most pronounced when PCV was measured in low concentration samples. The microcentrifuge showed good limits of agreement regardless of sample concentration. The data suggests that measurement of PCV by either continuous monitoring or by a blood gas analyser is not an accurate alternative to an established laboratory method. The microcentrifuge is the most accurate method of the ones investigated to measure haematocrit during CPB.

[Giant peripheral tear of the retinal pigmented epithelium]. / Déchirure géante et périphérique de l'épithélium pigmentaire rétinien.

The authors present a case of gigantic tear of the retinal pigmented epithelium. This tear was situated in the middle periphery and seems to have appeared spontaneously together with a carotid-cavernous fistula. The functional outcome was favorable. The authors deal with the various possible patho-physiological mechanisms.

[Double-blind study of the comparative action of indomethacin 0.1% and placebo on the breakdown of the blood-retinal barrier]. / Etude en double insu de l'action comparée de l'indométacine à 0.1% et d'un placebo sur la rupture de la barrière hémato-aqueuse.

The oral fluorophotometric exploration is able to simultaneously quantify the permeability of the blood aqueous (KIN, KOUT) and blood-retinal (PVPR) barriers. It is possible to detect the breakdown of the blood aqueous barrier 3 days after cataract surgery with this fluorophotometric method. Ocular inflammation is responsible for this leakage and non steroidal anti-inflammatory drugs prevent this breakdown. In this paper, we studied the effect of 0.1% indomethacin treatment to patients before and after cataract surgery. This double-blind study was performed in 34 patients: 18 patients in the indomethacin group and 16 patients in the placebo group. We showed that the apparent transfer coefficient of fluorescein in the anterior chamber (KIN) was statistically lower in the indomethacin group (0.0220 +/- 0.0179 hr-1) than in the placebo group (0.0371 +/- 0.0187 hr-1) on the 3rd postoperative day (p = 0.027).