A profile of intravenous nitroglycerin use in cardiopulmonary bypass surgery

Use of prostaglandin E1 to treat peri-anaesthetic pulmonary hypertension associated with mitral valve disease

Severe pulmonary hypertension (PH) can be a critical problem during and after cardiac surgery, since it increases right ventricular afterload resulting in decreased cardiac output. A case of pulmonary hypertension associated with mitral valve disease and resistant to glyceryl trinitrate therapy during surgery is reported. The case was treated successfully with prostaglandin E1 (PGE1), indicating that PGE1 can be used peri-operatively in a patient with refractory PH resistant to glyceryl trinitrate treatment.

[Vascular effects of nicergoline]

The vascular effects of nicergoline, a post-synaptic alpha receptor antagonist, were studied using a total haemodilution non pulsatile normothermic cardiopulmonary bypass with a bubble oxygenator during cardiac surgery. Anaesthesia was induced with fentanyl 30 micrograms.kg-1 and diazepam 0.25 mg.kg-1 and maintained with incremental doses of fentanyl. All the patients were intubated using pancuronium bromide (0.1 mg.kg-1) and artificially ventilated (FIO2 = 1). Nine patients randomly selected received 10 ml of saline (group 1) and 11 other 5 mg nicergoline (group 2) into the venous line of the extracorporeal circuit. Pump flow remained constant during 10 min. Arteriolar resistance was assessed by mean arterial pressure recording and venous capacitance by the level of venous reservoir. Statistical analysis was carried out using analysis of variance and the Newman-Keuls test. In group 1, arteriolar resistance increased by 17.0 +/- 21.8% at 10 min (not significant), whereas in group 2 it decreased by 22.8 +/- 8.1% at 2 min (p less than 0.05) and then increased slowly. It then remained 18% lower than in group 1 at 10 min. In group 1, venous capacitance decreased regularly by 1 ml.kg-1.min-1 during 10 min (-10.0 +/- 6.2 ml.kg-1 at 10 min), whereas in group 2 it decreased up to the 6th min (-4.2 +/- 3.3 ml.kg-1) and then remained stable, with a 5.4 ml.kg-1 difference with group 1 at 10 min (p less than 0.05). Therefore, nicergoline seemed to cause venoconstriction during cardiopulmonary bypass, possibly through a baroreflex mechanism.

Reactive pulmonary hypertension after a switch operation. Successful treatment with glyceryl trinitrate

After an arterial switch operation (anatomical correction for transposition of the great arteries) in a 6 month old child reactive pulmonary hypertension developed six hours after cardiopulmonary bypass. Intravenous glyceryl trinitrate was the only means by which the pulmonary hypertension could be reversed.