**8. Medical treatment**

### **Aspirin**

32 Special Topics in Cardiac Surgery

vasopressin has been used for this treatment with encouraging results. Masseti and colleagues studied 16 patients with intravenous vasopressin (0.1-1 IU / min) for the treatment of hypotension refractory to maximum dose of norepinephrine (> 30 mg / kg / min). Preoperative ejection fraction was 40.5% and NYHA functional class 3.5. Getting an increase in blood pressure of 89 mmHg baseline to 116, increase in SVR from 688 to 1043, decreased cardiac index from 2.6 to 2.9 L/min/m2, urine volume increased from 36.8 to 72.8

Whereas high doses of vasopressin and effective in the treatment of Sx vasoplegic after

In a recent study, Argenziano et al found that about 10% of patients undergoing cardiac surgery experienced hypotension by vasodilation after bypass surgery, which not necessarily is associated with cardiogenic or septic shock. Interestingly, in situations in which hypotension persists after surgery RVM, smooth muscle cells become less sensitive to circulating catecholamines. This phenomenon is due to decreased function of adrenergic receptors, the study of 50 patients conducted at Columbia Presbyterian Medical Center undergoing cardiac surgery were treated with vasopressin in the operating room or intensive therapy in the first 24 hr surgery (6). All patients had less than 60 mmHg TAM and decreased systemic resistance, despite support with catecholamines. This administration of vasopressin infusion of 0.09 U / min increased the TAM from 58 to 75 mmHg, the SVR increased from 920 to 1200 dyne s cm and achieving a reduction in the administration of

Brain natriuretic peptide also known as BNP is a neurohormone secreted by the left ventricle in response to increased stress (both pressure and volume in the varga) in the ventricular wall. Physiological actions of BNP include natriuresis, vasodilation and neurohormonal modulation. So the tx with BNP has emerged as a viable option in the tx of acute CHF. Moreover, its determination of serum is currently used to differentiate cardiac dyspnea pulmonary dela type. In general, levels of BNP 100pg/ml excludes minors 1 decompensated CHF, whereas values greater than 500pg/ml indicates

Neseritide is the recombinant form of endogenous human BNP. Has been shown to decrease filling pressures, increase cardiac output and improve the clinical condition of patients with decompensated CHF. In August 2001 was approved by the FDA for tx of CHF in those with decompensated dyspnea at rest or with minimal effort. The recommended dose is 2μg/kg initial bolus followed by infusion of 0.01μg/kg/min

Several studies have examined the possible application of perioperative neseritide so, in patients with left ventricular dysfunction who will undergo heart surgery. In a study prospectivco, open, randomized controlled, Brackbill et al examined the use of perioperative infusion of neriritide and showed improvement compared with milrinone. We included 40 hemodynamically stable patients with LVEF 35% or less that were undergoing bypass surgery. And they were randomized to a bolus of nesiritide or milrinone intraoperatively followed by an infusion of any of them for 24 hr. The time spent in post-qx therapy was the primary outcome measure. The incidence of post-qx ICC, the rate of readmission within 30 days, mortality and other clinical parameters were compared. Patients receiving nesiritide had a hospital stay of 50.6 + / - 46.8 hours

ml / h.

norepinephrine in 32%.

**Nesiritide** 

decompensation.

extended to a maximum of 48 hr.

cardiac surgery with cardiopulmonary bypass.

There are currently a total of 8 studies with more than 2500 patients using aspirin CSRC. The doses used 325-1200 mg daily. Two of these studies showed significant benefit of aspirin a day after heart surgery. In contrast to the other 6 that saw no difference vs placebo with regard to occlusion of the bridges managed belatedly. In conclusion, the evidence so far suggests that the use of aspirin to reduce occlusion of coronary artery bypass bridges to 12 months after CSRC when given the 1st day after surgery, on the other hand is a medicine economic which is associated with few adverse effects and is of great benefit for patients with coronary artery disease peripheral with that aspirin should be given the most quickly as possible after cardiac surgery and continued indefinitely.

### **HIipolipemiantes**

There are three studies involving 1900 patients to evaluate the use of these agents on the occlusion of coronary artery bypass grafts and the risk of cardiovascular events): The Post-CABG trial, LOCATE (Lopid Coronary Angiography Trial) and Cholesterol Lowering Atherosclerotic Study ( CLAS). All three showed a significant reduction in the progression of atherosclerosis in coronary artery bypass bridges. Thus the long-term use of lipidlowering drugs prevent the progression of atherosclerosis in both native arteries and in coronary bridges and reduces cardiovascular events, it was shown that the use of these agents reduces the progression of atherosclerosis after 2 years RVM.

Pan et al, found that after adjusting the demographic and clinical differences, the preoperative use of statins was associated with a 50% reduction in mortality, but showed no benefit in the occurrence of AF or IM. Dotan et al, found that statins were associated

Intensive Care Management of Patients in the First 24 Hours After Cardiac Surgery 35

patients treated with high doses of heparin than in those treated with low-dose heparin

 Lifetime in patients with biological valves who have other indications for anticoagulation Vgr: atrial fibrillation, heart failure, ventricular ejection fraction less

 For the first three months in patients with bioprostheses after insertion, with a target INR of 2.5. No emabrgo strategy with aspirin (low dose-100 mg DE75) is an alternative, but there have been no randomized studies supporting the safety of this strategy. There is no consensus at the time of initiation of anticoagulation after surgery, but should

[1] Lyons AS, Petruccelli RJ II. Medicine and illustrated history. New York: HN Abrams Inc,

[4] Casey LC. Roles of cytokines in the pathogenesis of multisystem organ failure induced

[5] Huddy SP, Joyce WP. Pepper JR. Gastrointestinal Complications in Patients Who underwent cardiopulmonary 4.473 bypass surgery. Br J Surg 1991; 78:293-296. [6] CHV Thakar, Jared JP, Worley S, Cotman K, Paganini EP. Renal dysfunction and Serious

[7] Laffey J, Boylan J, Cheng D. The systemic inflammatory response to cardiac surgery.

[8] Kollef MH, Wragge T, Pasque Ch Determinants of Mortality and multiorgan dysfunction

[9] Kalfin RE, Engelmann RM, Rousseau JA, Flack JE III, Deaton DW, Kreutzer DL, DK

[10] Ascione R, Lloyd CT, Underwood MJ, Lotto A, Pitsis AA, Angelini GD. After coronary

[12] Pizzo PA. Empirical therapy and prevention of infections in the immunocompromised

[13] Rossi F. The O2-forming NADPH oxidase of the phagocyte: nature, Mechanisms of

activating and function. Biochim Biophysics Acta 1984, 853:65-71.

in cardiac surgery Patients Requiring Prolonged mechanical ventilation. Chest

Dash. Induction of interleukin-8 expression cardiopulmonary bypass DURING.

revascularization Inflammatory response With or Without cardiopulmonary bypass prospective randomized study. Ann Thorac Surg 2000; 69: 1198-1204. [11] Nilsson L, Kulander L, Sven-Olov N, Eriksson O. Endotoxins in cardiopulmonary

host. In: Mandell GL, Bennett JE. Dolin R, editors. Principles and practice of infectious diseases. 5th edition. New York: Churchill-Livingstone, 2000. pp. 3102-

[2] Vesalius A. De humani corporis fabrica. Budapest: Corvina / Magyar Helikon, 1972. [3] Rutkow IM. Surgery. An illustrated history. St. Louis, Baltimore, Boston, Chicago,

London, Madrid, Philadelphia, Sydney, Toronto: Mosby, 1993.

Infections After open-heart surgery. Kidney Int 2003; 64:239-246.

cardiopulmonary. Ann Thorac Surg 1993; S6: S92-S96.

for prevention of venous thrombosis.

than 30% left.

**10. References** 

1978.

3112.

Anticoagulation is recommended in the following cases: Lifetime on all patients with mechanical valves

begin during the first days postoperatively. (5 + -2)

Anesthesiology 2002; 97:215-252.

Circulation 1993; 88 [Part 2]: 401 - 406.

bypass. J Thorac Cardiovasc Surg 1990; 100:777-780.

1995; 107 (5) :1395-1401.

with a significant decrease in cardiac mortality, unstable angina and arrhythmias 60 days to 1 year.

### **Beta blocker**

Its use has been assessed by many studies, but in a perioperative cardiac surgery, Sjölander et.al, conducted a controlled double-blind study of 967 patients with MVR. Patients were randomized 4 to 21 days after RVM receiving 50 mg of metoprolol 2 times per day x 2 weeks and 100 mg of metoprolol per day vs placebo 2 x 2 years. There was no significant difference between the 2 study arms with respect to exercise capacity, however cn patients placebo had a higher rate of chest pain compared with the metoprolol group. On the other hand no significant difference in both groups with regard to revascularization, unstable angina, nonfatal MI or death at 2 years of follow-up.

Finally, Ferguson et al, in a cohort study investigated the use of preoperative B-blocker in 629 877 patients undergoing CSRC and showed a reduction to 30 days of drug-related mortality (OR 0.90, 95% CI0.87-0.93 ). This decrease was consistent with all groups of patients except those with LVEF <30% where there was no demonstrated benefit.

### **Calcium antagonist**

Only one study has examined the effect of calcium antagonists initiated after surgery RVM, Gaudino et al; evaluating the benefits of calcium antagonists after the first year of revascularization. A total of 120 patients with normal perfusion function were randomized after 1 year of tx with 120 mg diatiazem to continue with or stop. No significant differences after 4 years of follow-up among the group of calcium antagonists and those who discontinued tx with respect to recurrence of angina (10% vs 12%), residual ischemia, 17% vs 18%) and cardiac death 2% vs 0%). In short there is little evidence to support the routine use of calcium antagonists or nitrates after cardiac surgery.

### **ACEI**

Despite the known benefits of ACE inhibitors, only 4 studies examined perioperative prophylactic use of ACE inhibitors in patients with MVR. QUO VADIS In the study 149 patients were randomized to quinapril 40mg/día or placebo for 4 weeks before elective surgery RVM, treatment was continued for 1 year. The researchers found that quinapril significantly reduced 1-year clinical events, such as death from cardiovascular causes.
