Objective To compare milrinone （MIN）, Phenoxybenzamine （PHE），and mixture of nitroglycerin and verapamil(NVC) for the prevention and treatment of human radial artery spasm. Methods Residuary radial arteries from 30 patients undergoing coronary artery bypass grafting （CABG） using autologous radial artery from March to September of 2012 in General Hospital of Shenyang Military District were collected. All the artery specimens were cut into 60 vessel rings of 3 mm in width and hanged in the Organ-Bath. Using a random number table，all the vessel rings were divided into 4 groups：PHE group，NVC group，MIN group and blank group （control group）. Firstly，20 vessel rings were used for spasm relaxation experiment with 5 rings in each group. Phenylephrine was added into the Organ-Bath to reach final concentration of 10-3 mol/L in order to cause vessel rings spasm. PHE of 1 mmol/L，NVC of both 30 μmol/L，MIN of 30 μmol/L and Krebs-Ringer’s solution were added respectively into above groups to compare the relaxant effect of these vasodilators on radial artery spasm. Secondly，the other 40 vessel rings were used for spasm prevention experiment with 10 rings in each group. All the 40 vessel rings were dipped in above 4 groups. After 30 minutes，phenylephrine was added to the Organ-Bath to reach final concentration of 10-3 mol/L. Time-dependent constriction of the vessel rings were compared to examine the prevention effect of these vasodilators on radial artery spasm. Results In the spasm relaxation experiment, vessel ring spasm relaxed most quickly in NVC group （P＜ 0.01）. Vessel rings in MIN group relaxed more slowly but steadily （P＜ 0.05）. Vessel rings in PHE group relaxed most slowly （P＜0.01）. And there was no relaxation in the control group. In the spasm prevention experiment，vessel rings in the control group contracted （spasm） 100% immediately after phenylephrine administration. Vessel rings in MIN group contracted immediately after phenylephrine administration too，but slower than the control group（P＜0.01）. Vessel rings in NVC group did not contract right after phenylephrine administration，but the sedentary tension of these vessel rings gradually increased 120 minutes after phenylephrine administration，and vessel ring contraction reached 46.89% 240 minutes after phenylephrine administration. There was no vessel ring contraction in PHE group. Conclusions All the vasodilators in our experiment are effective for the prevention and treatment of radial artery spasm to different degree，but each medication has its own characteristics，vasodilatation result and time-dependent effect. NVC is most effective to dilate radial artery which has been in spasm state, while radial artery pretreated by PHE is least to become spasm after being stimulated.
Abstract： Objective To explore clinical outcomes of nitroglycerin perfusion via the aortic root before heart re-beating for patients undergoing heart valve replacement. Methods A total of 254 patients with valvular heart diseases underwent heart valve replacement in Beijing Anzhen Hospital from January 2008 to December 2011. According to whether or not they received nitroglycerin perfusion via the aortic root before heart re-beating during cardiopulmonary bypass （CPB）， all the 254 patients were randomly divided into two groups， the nitroglycerin group and the control group. There were 134 patients in the nitroglycerin group including 57 males and 77 females with their average age of 58.47±12.34 years. They received aortic root perfusion of 5 mg nitroglycerin diluted into 20 ml after full de-airing of the heart， and repeated aspiration was performed 8 to 10 times before heart re-beating during CPB. Aortic cross-clamp was released after the heart showed signs of automatic re-beating， and the aortic root was squeezed in high frequency by hand to make sure that the aorta was squeezed to close each time. In the control group， there were 120 patients including 64 males and 56 females with their average age of 61.85±11.97 years. Patients in the control group received routine procedures of CPB except nitroglycerin perfusion before heart re-beating. Automatic heart re-beating rate， CPB supporting time after heart re-beating， postoperative usage of inotropic drugs， mechanical ventilation time， perioperative morbidity and length of hospital stay were compared between the 2 groups， and patients were followed up and further evaluated. Results There was no in-hospital death. CPB supporting time after heart re-beating（12.32±9.76 min vs. 23.43±10.33 min， t=-1.233， P=0.000）， dopamine usage［3.45±2.33 μg/ （kg?min） vs. 5.67±3.12 μg/ （kg?min） ， t=-0.943 ， P=0.034］ and epinephrine usage ［0.026±0.013 μg/ （kg?min） vs. 0.056±0.021 μg/ （kg?min） ， t=-0.822 ， P=0.027］ of the nitroglycerin group were significantly shorter or lower than those of the control group. Automatic heart re-beating rate of the nitroglycerin group was significantly higher than that of the control group ［97.01% vs. 66.67 % ， χ 2 =-2.115 ， P=0.000］. A total of 121 patients in the nitroglycerin group were followed up for 2-36 months， and 13 patients were lost during follow-up. There was no death during follow-up. Conclusion For patients undergoing heart valve replacement， some myocardial protection strategies including nitroglycerin perfusion via the aortic root before heart re-beating， use of norepinephrine， and aortic root squeezing in high frequency by hand can significantly increase the automatic heart re-beating rate， shorten the CPB supporting time after heart re-beating， and improve postoperative clinical outcomes.
Abstract: Objective To compare the effects of nitroglycerine (NTG)， Verapamil(VP), papaverine(PA) and the mixed solution of Verapamil and nitroglycerine (VG) on relaxing function of human radial arteries. Methods The radial arteries of thirty patients were used during the operation of coronary artery bypass grafting (CABG). A short segment (1.0-1.5cm) of radial arteris were taken from the distal end of radial arteries of each patient and were cut into vascular rings, which were mounted in the organ bath chamber and then subject to a series of tests for vascular smooth muscle viability and endothelial integrity. The effects of five storage solutions on the relaxing function were evaluated by “OrganBath” technique. The five solutions included: (1) Ringer’ s solution (control group); (2) VP solution (VP group); (3) NTG solution (NTG group); (4) PA solution (PA group); (5) VG solution (VG group). First, challenged with phenylephrine (10-5mol/L), vasorelaxant effect of these drugs (effect onset and efficacy) was observed at different time point and resting tension was recorded. Second, after 30min preincubation with either verapamil, papaverine, phenoxybenzamine or VG mixture, potassium chloride (final concentration of 60mmol/L) was added in the organ bath chamber and then vasoconstriction was observed subsequently. Finally, after 30min pretreatment of different antispasmodic agent in the same way as described above, the vascular rings were mounted in organ bath chamber and challenged with phenylephrine(10-5mol/L). Vascular spasticity and vosospasm duration were observed at different time point which might provide guidance for optimal timing of clinical application. Results The radial arteries in VG, VP, NTG and PA solutions were relaxed in 11 min after vasospasm and there was no difference between them (Pgt;0.05). But during the initial three minutes，the relaxation effect of VG and NTG was significantly better than other two groups. Relaxation curve showed that the ability of vasodilatation of VG, NTG, VP and PA decreased in order. In the experiment about antivasospasm pretreatment of radial arteries, there was no difference between VG and VP group (Pgt;0.05 ), whose effects were better than NTG and PA group(Plt;0.05 ). After cold storage for 24h, VG and VP still could prevent vasospasm. But NTG and PA hardly had any function and there was no difference compared with the control group (Pgt;0.05 ). Conclusion Although in the final all these drugs could prevent and relieve vasospasm of radial arteries in the different level, it appeared that a combination of verapamil and nitroglycenn is more fit for treating radial artery during CABG operation than other drugs.
Objective To investigate the effect of nitroglycerin on preventing post-endoscopic retrograde cholangiopancreatograph (ERCP) pancreatitis (PEP) and hyperamylasemia. Methods One hundred patients diagnosed as common bile duct stones by CT or MRI and planned to undergo ERCP, EST and stones removal under endoscopy were selected from January to December 2008 in Shandong Jiaotong Hospital. These patients were randomly divided into 2 groups: nitroglycerin group (n=50), in which 0.5 mg nitroglycerin was given sublingually in 5-10 min before ERCP; control group (n=50), in which no nitroglycerin was given. The levels of serum amylase of all the patients before ERCP and at 3 h, 24 h after ERCP were detected and the incidence of hyperamylasemia and PEP were also observed. Results The level of serum amylase between 2 groups before ERCP was not significantly different (P＞0.05). The levels of serum amylase at 3 h and 24 h after ERCP were significantly higher than that before ERCP in 2 groups. The level of serum amylase in nitroglycerin group were respectively lower than that in control group at 3 h and 24 h after ERCP 〔3 h: (108.88±152.07) U/L vs. (196.30±244.41) U/L; 24 h: (97.02±113.38) U/L vs. (234.22±406.05) U/L〕， P＜0.05. The incidence of hyperamylasemia (12.00%, 6/50) and PEP (2.00%, 1/50) in nitroglycerin group was respectively significantly lower than that in control group (hyperamylasemia: 30.00%, 15/50; PEP: 14.00%, 7/50）， P＜0.05. Conclusion Sublingual nitroglycerin can decrease the level of serum amylase and prevent PEP and hyperamylasemia.