Spinal anesthesia reduces postoperative delirium in opium dependent patients undergoing coronary artery bypass grafting.

We investigated the effect of high spinal anesthesia on postoperative delirium in opium dependent patients undergoing coronary artery bypass grafting (CABG). The study was conducted in a tertiary referral university hospital on a population of 60 opium dependent patients undergoing CABG surgery. Patients were divided into two groups based on anesthesia protocol. One group were given general anesthesia (GA Group), the other group additionally received intrathecal morphine and bupivacaine (SGA Group). Postoperative delirium (POD) was defined as the main outcome of interest. Incidence of POD was significantly higher in patients of GA Group as compared with those in SGA Group (47% and 17% for GA and SGA respectively; P-value = 0.01). Time to extubation was on average 2.2 h shorter in SGA than in GA (7.1 h and 9.3 h respectively, P-value < 0.001). Intrathecal morphine and bupivacaine reduced the risk of POD after CABG in a population of opium dependent patients.

Effect of persistent opium consumption after surgery on the long-term outcomes of surgical revascularisation.

BACKGROUND: A wrong traditional belief persists among people that opium consumption beneficially affects cardiovascular disease and its risk factors. However, no evidence exists regarding the effect of opium consumption or cessation on the long-term risk of major adverse cardio-cerebrovascular events after coronary artery bypass grafting. We therefore aimed to evaluate the effect of persistent opium consumption after surgery on the long-term outcomes of coronary artery bypass grafting. METHODS: The study population consisted of 28,691 patients (20,924 men, mean age 60.9 years), who underwent coronary artery bypass grafting between 2007 and 2016 at our centre. The patients were stratified into three groups according to the status of opium consumption: never opium consumers (n = 23,619), persistent postoperative opium consumers (n = 3636) and enduring postoperative opium withdrawal (n = 1436). Study endpoints were 5-year mortality and 5-year major adverse cardio-cerebrovascular events, comprising all-cause mortality, acute coronary syndrome, cerebrovascular accident and revascularisation. RESULTS: After surgery, 3636 patients continued opium consumption, while 1436 patients persistently avoided opium use. The multivariable survival analysis demonstrated that persistent post-coronary artery bypass grafting opium consumption increased 5-year mortality and 5-year major adverse cardio-cerebrovascular events by 28% (hazard ratio (HR) 1.28, 95% confidence interval (CI) 1.06-1.54; P = 0.009) and 25% (HR 1.25, 95% CI 1.13-1.40; P < 0.0001), respectively. It also increased the 5-year risk of acute coronary syndrome by 34% (sub-distribution HR 1.34, 95% CI 1.16-1.55; P < 0.0001). CONCLUSIONS: The present data suggest that persistent post-coronary artery bypass grafting opium consumption may significantly increase mortality, major adverse cardio-cerebrovascular events and acute coronary syndrome in the long term. Future studies are needed to confirm our findings.

Pancuronium, vecuronium, and heart rate during anesthesia for aortocoronary bypass operations.

To determine the effects of pancuronium and vecuronium on heart rate, 90 patients scheduled for aortocoronary bypass were randomly assigned to one of three groups (30 patients each) which received vecuronium 100 micrograms[sdot]kg-1, pancuronium 100 micrograms[sdot]kg-1, or a mixture of vecuronium (50 micrograms[sdot]kg-1) and pancuronium (50 micrograms[dot]kg-1) in a double-blind fashion during induction of anesthesia. All patients were premedicated with lorazepam prior to surgery, hence avoiding the effects of scopolamine. Our results showed no significant increase in heart rate from the administration of pancuronium, following administration of this drug the heart rate increased by only four beats per minute. The heart rate was unchanged after the mixture, but decreased by twelve beats per minute after vecuronium (P < 0.05). The heart rate response differed by 16 beats per minute between pancuronium and vecuronium. All patients who received either of the neuromuscular relaxants and who were on beta blockers showed a decrease in heart rate. In this study, the administration of pancuronium after an adequate induction dose of fentanyl did not cause tachycardia. We therefore feel that pancuronium still has a role in cardiac anesthesia, especially as the newer muscle relaxants such as vecuronium, pipecuronium and doxacurium are significantly more expensive.

Heparin induced thrombocytopenia. Experiences in 12 heart surgery patients.

A heparin induced thrombocytopenia Type II (HIT) is a dangerous complication of heparin therapy. Bleeding, but above all serious thromboembolic complications, which may result in crippling disabilities or even death, can develop. Twelve heart surgery patients who were diagnosed with a HIT Type II are reported. Seven of the patients were diagnosed post operatively, the other five pre-operatively. Two of these patients underwent heart surgery with r-Hirudin (Behringwerke AG, Marburg, Germany) on cardiopulmonary bypass and two on Orgaran (AKZO Organon, the Netherlands). Of the seven post operative HIT patients, four had had a bypass operation and each had received a mitral or aortic valve replacement. Another patient had received an artificial biventricular support system (Berlin Heart) and was diagnosed with HIT Type II post operatively. Because of his special condition, this patient underwent anticoagulation with Orgaran and heart transplantation with Orgaran on a heart lung machine. Upon suspicion of HIT Type II, heparin therapy was immediately halted and an alternative treatment of Orgaran or r-Hirudin was begun. One patient encountered bleeding of a gastric ulcer on Orgaran therapy. Heart surgery patients, especially patients with an artificial support system, are potentially lethally threatened by serious thromboembolic complications accompanying HIT Type II. Therefore, these patients must be diagnosed as early as possible. Orgaran along with r-Hirudin are effective heparin substitutes in patients with HIT Type II. These medications can be widely administered to heart surgery patients pre-, intra-, and post operatively without complication.

[Use of Organon, a synthetic heparinoid, in two cardiopulmonary bypass procedures in the same patient sensitive to heparin]. / Utilisation de l'Orgaran, héparinoïde de synthèse, lors de deux circulations extracorporelles, chez un même patient allergique à l'héparine.

We report the case of a patient who underwent two cardiopulmonary bypass (CPB) procedures with Orgaran because of heparin-induced thrombocytopenia. A 38 years-old man with ischemic mitral insufficiency was operated for coronary artery bypass and valvular replacement. The CPB was carried out with heparin. Heparin-induced thrombocytopenia occured and was proven immunologically. Two months later, a new valvular replacement was performed because of paravalvular leak due to endocarditis. The Orgaran-CPB protocol was as follows: 5,000 units before cardiopulmonary bypass, 5,000 units in the priming volume, anti-Xa level between 0.9 and 1.1 units/mL, with injection of 1,500 units if necessary, no administration of protamine. One month later, a new valvular replacement was necessary and performed with the same protocol using Orgaran. No bleeding or thrombotic complication occurred. Orgaran is a safe and reliable anti-thrombotic substitute if anti-Xa activity is closely monitored.

Acupuncture anesthesia for open heart surgery: a report of 800 cases.

This article reports the utilization of acupuncture in combination with chemical anesthesia and neuromuscular relaxant for patients with cardiac surgery, including valvular disease and by-pass. In 800 patients studied using this type of combination of anesthetic techniques, it was found that this procedure can be successful for cardiac surgery and that it allows light planes of anesthesia with less interference to circulatory regulation. There is a certain advantage of using acupuncture anesthesia when compared with chemical anesthesia, as the pharmacological agents are not used and hence post no metabolic load for the patients. From the 800 patients studied, it seems justifiable to recommend this anesthetic procedure for cardiac surgery.

Slow EEG-power spectra correlate with haemodynamic changes during laryngoscopy and intubation following induction with fentanyl or sufentanil.

We studied nociception-associated arousal following laryngoscopy and intubation in patients scheduled for elective open heart surgery, using EEG power spectra and hemodynamics. Either fentanyl (7 micrograms/kg; n = 30) or sufentanil (1 microgram/kg; n = 30) were given in a randomized fashion to induce anesthesia in heavily premedicated patients, followed by pancuronium bromide (100 micrograms/kg). EEG-power spectra (delta, theta, alpha, beta) as well as mean arterial blood pressure (MAP) and heart rate (HF) were measured at the following end-points: before the induction of anesthesia (control), 1 and 10 minutes after laryngoscopy and intubation (L & I). Linear regression analysis was computed to determine which of the EEG power spectra was most sensitive to detect insufficient blockade of nociceptive-related arousal when correlated with haemodynamics. In the fentanyl group the change in HF closely correlated with the decrease of power in the slow delta- and theta-domain (r2 = 0.98 and r2 = 0.89 respectively) of the EEG. The change in MAP also closely correlated with a decrease in the slow delta- and theta-domain (r2 = 0.97 and r2 = 0.99 respectively). There was little correlation in regard to spectral edge frequency (SEF) and HF and MAP changes (r2 = 0.36 and r2 = 0.12 respectively). In the sufentanil group the change in HF correlated closely with an increase of power in the fast alpha and a decrease in the slow theta-domain (r2 = 0.91 and r2 = 0.98 respectively) of the EEG. The changes in MAP closely correlated with an increase in the fast alpha-band a decrease in the slow theta-domain (r2 = 0.98 and r2 = 0.73 respectively). Also there was little correlation of SEF with HF and MAP changes (r2 = 0.09 and r2 = 0.02 respectively). Among the EEG-spectra, reduction of power in the slow delta- and theta-bands are the most sensitive parameters to determine insufficient antinociception of opioids commonly used for the induction in cardiac anesthesia. Increase of power in the alpha-band seems to be closely correlated with cortical reactivation and reduction of hypnosis, while a reduction of power especially in the deltabut more so in the theta-band of the EEG reflects nociception related arousal.

[Anesthetic induction with Althesin or diazepam in patients undergoing an aortocoronary bypass]. / Induction anesthésique avec Alfatésine ou diazépam chez des patients opérés pour pontage aorto-coronarien.

The haemodynamic effects of induction of anaesthesia with diazepam (group D) and Althesin (group A) were studied in 25 coronary patients under betablockers with good myocardial function. Haemodynamic variables monitored were vascular pressures, cardiac output and systolic time intervals. The effects of both drugs were observed when used alone (time I) and in combination with fentanyl, pancuronium and nitrous oxide (time II). The results seemed to show that Althesin (12.51% fall in SI and 10.79% increase in PEP/LVET) depressed myocardial function more than diazepam (no significant difference), but the introduction of fentanyl, pancuronium and nitrous oxide removed the differences between the drugs as to their effect on myocardial performance. These drugs added a depressant effect to diazepam (13.83% fall in SI and 15.77% increase in PEP/LVET) without increasing Althesin's negative inotropic effect. However, in group A at time II, the pulmonary arterial pressure, the wedge pressure and the pulmonary vascular resistance were significantly reduced, while they remained stable in the diazepam group.

[Maintenance doses of vecuronium and pancuronium during hypothermic cardiopulmonary bypass].

In 31 patients undergoing coronary artery bypass grafting, we investigated the maintenance doses of pancuronium and vecuronium during hypothermic cardiopulmonary bypass. For all patients, the height of the first twitch of the train-of-four (T1) was measured with evoked electromyogram. During operation, T1 was kept from 5 to 15 per cent of control. Infusion doses of both muscle relaxants were controlled with a personal computer. During hypothermic cardiopulmonary bypass (body temperature 28 degrees C), requirement of both muscle relaxants decreased for about 90 per cent compared with pre bypass values. We consider that the prolongation of neuromuscular blockade is attributable to hypothermia rather than to other factors of cardiopulmonary bypass. After rewarming, maintenance dose of vecuronium remained about a half of the dose required in pre-bypass period. It suggests that elimination of vecuronium from liver and kidney is hindered not only during hypothermia but also after rewarming.

[A comparison of pancuronium and vecuronium used during the induction of high-dose fentanyl anesthesia].

Effects on hemodynamics and blood catecholamine levels of pancuronium and vecuronium used during the induction of anesthesia, were studied in patients undergoing coronary artery bypass grafting. Anesthesia was induced out with fentanyl, 70 micrograms.kg-1, and diazepam, 0.2 mg.kg-1, and either pancuronium or vecuronium was administered in a dose of 0.2 mg.kg-1. Control measurements were made before the induction of anesthesia. Hemodynamic parameters and blood levels of norepinephrine (NEP) and epinephrine (EP) were measured three minutes (S1) and ten minutes (S2) after tracheal intubation. The study showed that HR, AP, CI, and coronary perfusing pressure were more stable in the group of patients receiving pancuronium (group P) than in the group receiving vecuronium (group V) during the induction of anesthesia. LVSWI and RVSWI showed a comparable decline in both groups. While NEP was unaffected in group P during the induction of anesthesia, it decreased significantly at S1 and S2, compared with control (S0), in group V. On the other hand, EP decreased significantly at S1 and S2 during the induction of anesthesia in both groups, but group V showed a greater change. The results of this study suggest that pancuronium is more advantageous than vecuronium as a muscle relaxant used during the induction of high-dose fentanyl anesthesia.

Hemodynamic effects of diazepam-vecuronium-fentanyl sequence for induction of anesthesia for coronary artery surgery.

The hemodynamic effects of diazepam (0.2 mg/kg)--vecuronium (0.2 mg/kg)--fentanyl (10 micrograms/kg) sequence was investigated when used for induction of anesthesia and tracheal intubation in eleven patients undergoing CABG. The parameters monitored included HR, SBP, PAP and PCWP. Also, EKG was monitored via a modified V5 lead and C.O was measured by thermodilution. SVR, PVR and SV were computed from the measured parameters. Following induction of anesthesia by diazepam-vecuronium-fentanyl sequence, there was a decrease in SBP by 20.0% (P less than 0.05), in HR by 15.7% (P less than 0.001) in C.O by 13.3% (P less than 0.01) and in SVR by 13.6% (P less than 0.05) of control value. There were no changes in PAP, PCWP, PVR and SV. Coronary perfusion pressure and heart rate product were both decreased following this induction sequence. However, the percentage decrease in PR was higher than that of CPP, affecting favorably the myocardial oxygen supply-demand balance. Orotracheal intubation was followed by an increase of HR by 10.7% (P less than 0.05), SVR by 13% (P less than 0.05) and PCWP by 26% (P less than 0.05) of preceding value. However, all these values did not reach the control awake values. It was concluded that diazepam (0.2 mg/kg)--vecuronium (0.2 mg/kg)--fentanyl (10 micrograms/kg) sequence does not produce serious hemodynamic changes when used for induction of anesthesia and tracheal intubation in patients undergoing coronary artery bypass surgery.

Effects of opium addiction on bleeding after coronary artery bypass graft surgery: report from Iran.

PURPOSE: Opium abuse is a major type of drug abuse in Iran. This study was designed to find the possible relation between opium addiction and excessive bleeding after coronary artery bypass graft (CABG) surgery. METHODS: In a historical cohort study during a 1.5-year period, consecutive patients scheduled for elective CABG surgery were assigned to two group on the basis of having or not having the criteria for inhalational opium addiction. Before and after operations, the complete blood count, bleeding time, prothrombin time, partial thromboplastin time, and platelet count were checked for all patients. The volumes of infused red blood cells during and after the operation were recorded. After operations, the volumes of bleeding through the patients' chest tubes were recorded. The recorded data were analyzed using SPSS software version 11.5. Independent t, chi-square and repeated measure tests were used; and P < 0.05 was considered statistically significant. RESULTS: In total, 84 nonaddicted patients were assigned in group 1, and 110 patients who fulfilled the addiction criteria were assigned in group 2. Total bleeding from the three chest tubes was significantly different between the two groups (P = 0.001). The mean hemoglobin level, prothrombin time, partial thromboplastin time, and platelet counts before and after the operations were similar in the two groups. Opium-addicted patients received more packed red blood cells during and after the operations. CONCLUSION: Inhalational opium addiction might lead to more hemorrhage after CABG surgery. It is recommended that cardiac surgeons consider these patients at high risk for major complications after surgery.

Effect of opium use on short-term outcome in patients undergoing coronary artery bypass surgery.

PURPOSE: Data regarding the effect of opium use on short-term outcome in patients undergoing coronary artery bypass surgery are limited. We sought to assess the morbidity and in-hospital mortality of current and past users compared the data with those from nonusers of opium after coronary artery bypass grafting (CABG). METHODS: This is a descriptive analytical review of prospectively collected data on 782 consecutive male patients who underwent isolated CABG between January 2005 and December 2007. Of these, 708 (90.5%) were nonusers, 56 (7.1%) were current users, and 18 (2.3%) were former opium users of more than 4 weeks. The effect of opium usage on clinical, admission, and outcome variables were analyzed. RESULTS: Current opium users were younger (P = 0.004) and more likely to be cigarette smokers (P = 0.0004). Other demographic characteristics, major coronary risk factors, rates of postoperative complications, intensive care unit readmission, postoperative length of stay, and in-hospital mortality did not differ among the three groups. Current opium users needed less analgesic postoperatively (P = 0.0001), were significantly less compliant with medical and dietary recommendations after discharge (P < 0.0001), and were more likely to be rehospitalized with cardiovascular causes within 6 months after CABG surgery; these differences were much more pronounced for nonusers versus current users of opium (P < 0.0001). CONCLUSION: Continued use of opium is a significant predictor of rehospitalization with a cardiac cause within 6 months of CABG surgery. This may be partly due to the low compliance of these patients with treatment recommendations.

Can opium abuse be a risk factor for carotid stenosis in patients who are candidates for coronary artery bypass grafting?

BACKGROUND: Over the centuries, opium has been the most frequent substance abused in the Middle East. There are many controversial aspects about the effects of opioids on the atherosclerosis process, which is still unclear. METHODS: All patients who were candidates for coronary artery bypass graft in Tehran Heart Center were registered and evaluated for risk factors such as diabetes mellitus, hypertension, smoking status and duration, opium abuse, involved coronary arteries and left main branch lesion > 50%, carotid stenosis > or = 70%. RESULTS: A total of 1,339 patients were enrolled in the study, of whom 400 (29.9%) were female and the other 939 (70.1%) male. Female patients were omitted from analysis due to the low numbers of female opium addicts. Our study revealed that in the addicted population, the risk of diabetes and hypertension was lower than in the non-addicted group (p < 0.05 for each variable) and fasting blood sugar tended to be less in addicted ones, but the number of involved coronary arteries, left main stenosis > 50% and extent of carotid stenosis was not significantly different between the two groups. CONCLUSIONS: Our investigations demonstrate that opium is not cardioprotective, as has been claimed by some previous studies, and does not even decelerate atherosclerosis of carotid arteries in opium-addicted patients, but more evidence is still needed to completely prove the case.