Effects of phentolamine on tissue perfusion in pediatric cardiac surgery.
OBJECTIVE
To evaluate whether the deleterious effects of cardiopulmonary bypass (CPB) can be overcome by phentolamine-induced pharmacologic vasodilation in pediatric patients with congenital heart disease.


METHODS
Prospective, randomized, clinical study.


METHODS
Single university hospital.


METHODS
Forty-three pediatric patients undergoing open cardiac surgery for repair of congenital heart disease.


METHODS
Patients were randomly allocated into two groups. Patients in group 1 (n = 22) received 0.2 mg/kg of phentolamine during the cooling and rewarming periods of CPB. Group 2 patients (n = 21) did not receive phentolamine. Temperature measurements (rectal [R], nasopharyngeal [N], and toe [P]) and serum lactate values were obtained before, during, and after CPB; systemic oxygen consumption was evaluated during CPB.


RESULTS
At the end of the CPB period and at the end of the operation, lactate values of group 1 (1.87+/-0.37 and 1.8+/-0.39 mmol/L, respectively) were significantly lower than values of group 2 (2.24+/-0.28 and 2.33+/-0.33 mmol/L; p < 0.05 and p < 0.05, respectively). At the beginning of the rewarming period N-R temperature gradients of group 1 (0.14 degrees C+/-0.92 degrees C) were lower than group 2 (-0.58 degrees C+/-1.84 degrees C) values (p < 0.05). Central-peripheral temperature gradients of group 1 obtained at the end of the CPB period (N-R = 2.18 degrees C+/-0.69 degrees C; N-P = 7.84 degrees C+/-1.54 degrees C; R-P = 5.66 degrees C+/-1.70 degrees C) were significantly lower than the values of group 2 (N-R = 2.80 degrees C+/-0.91 degrees C, N-P = 9.97 degrees C+/-2.02 degrees C; R-P = 7.18 degrees C+/-2.10 degrees C; p < 0.05; p < 0.001; p < 0.05). At the end of the operation values of group 1 (N-R = 0.48 degrees C+/-0.31 degrees C; N-P = 6.30 degrees C+/-1.23 degrees C; R-P = 5.82 degrees C+/-1.16 degrees C) were significantly lower than the values of group 2 (N-R = 0.94 degrees C+/-0.56 degrees C; N-P = 8.69 degrees C+/-0.28 degrees C; R-P = 7.75 degrees C+/-2.15 degrees C; p < 0.05; p < 0.001; p < 0.001). The systemic oxygen consumption values of group 1 were higher than group 2 (6.26+/-1.82 v 5.17+/-1.05 mL/min/kg; p < 0.05) after complete rewarming. Mean arterial pressure (MAP) values of group 1 (58.9+/-6.4 mmHg) were lower than group 2 (63.4+/-6.7 mmHg) at the period after CPB (p = 0.03).


CONCLUSIONS
The results suggest that the use of phentolamine during CPB is associated with limited systemic anaerobic metabolism and more uniform body perfusion.
Köner
O
O
Department of Anaesthesiology and Intensive Care, Cardiology Institute of Istanbul University, Turkey.
Tekin
S
S
Köner
A
A
Soybir
N
N
Seren
S
S
Karaoglu
K
K
D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage / Q000627:therapeutic use*; D000693:Anaerobiosis / Q000187:drug effects; D001775:Blood Circulation / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D001831:Body Temperature / Q000187:drug effects; D002315:Cardiopulmonary Bypass / Q000009:adverse effects; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006330:Heart Defects, Congenital / Q000601:surgery*; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D007036:Hypothermia, Induced; D007223:Infant; D007231:Infant, Newborn; D007773:Lactates / Q000097:blood; D008297:Male; D010101:Oxygen Consumption / Q000187:drug effects; D010646:Phentolamine / Q000008:administration & dosage / Q000627:therapeutic use*; D011446:Prospective Studies; D017694:Rewarming; D012881:Skin Temperature / Q000187:drug effects; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000627:therapeutic use*
D000316:Adrenergic alpha-Agonists; D007773:Lactates; D014665:Vasodilator Agents; D010646:Phentolamine