Gastrointestinal complications following cardiac surgery

This study sought to determine which factors influence the mortality rate in patients developing gastrointestinal complications following cardiac surgery. Between July 1988 and January 1992, 2054 patients underwent cardiac surgical procedures at the Boston University Medical Center. Of these, 29 (1.4%) developed postoperative gastrointestinal complications. The overall mortality rate among these patients was 27% (8/29). Those who died following such complications had a higher incidence of New York Heart Association (NYHA) class IV and unstable symptoms (8/8, 100% versus 3/21, 14%; P < 0.0001), and an increased need for preoperative intra-aortic balloon pump support (4/8, 50% versus 1/21, 5%; P < 0.004). The need for gastrointestinal surgical intervention increased the mortality rate significantly compared with patients managed medically (8/18, 44% versus 0/11, 0%; P < 0.01). Patients with ischemic bowel also had a significantly higher mortality (5/5, 100% versus 3/24, 12%; P < 0.001). It is concluded that most patients with gastrointestinal complications following cardiac surgery can be treated, and with acceptable mortality rates. The presence of unstable symptoms, preoperative intra-aortic balloon pump support, ischemic bowel and the need for gastrointestinal surgical intervention adversely affect mortality.     

Thermoregulatory and metabolic responses following cardiac surgery

The thermoregulatory responses in 13 haemodynamically stable patients were evaluated over a 7-h period following coronary artery bypass graft surgery. Cutaneous vasoconstriction was defined by a forearm-to-fingertip skin temperature gradient (delta Tskin) > or = 4 degrees C and muscular hyperactivity was assessed by integrating the electromyographic signals (iEMG). Blood gases and lactate were measured in arterial, mixed venous and femoral venous blood. After arrival in ICU, we observed: (1) mild central hypothermia (Tc = 34.8 +/- 0.6 degrees C) and elevated peripheral vascular resistance in all the patients; (2) delta Tskin > or = 4 degrees C in 11 of 13 patients that persisted until a median Tc of 37.1 degrees C was achieved; (3) a transient increase in iEMG (+ 18%) was accompanied by an increase in total body O2 uptake (+ 28%); (4) elevated muscle O2 extraction rate (56 +/- 18% after 3 h) and lactate release. These data suggest that residual hypothermia in sedated patients after cardiac surgery elicits appropriate thermoregulatory responses that are associated with transient O2 supply/uptake mismatch within skeletal muscles.     

Early extubation following cardiac surgery in a veterans population

BACKGROUND: Early tracheal extubation is an important component of the "fast track" cardiac surgery pathway. Factors associated with time to extubation in the Department of Veterans Affairs (DVA) population are unknown. The authors determined associations of preoperative risk and intraoperative clinical process variables with time to extubation in this population. METHODS: Three hundred four consecutive patients undergoing coronary artery bypass graft, valve surgery, or both on a fast track clinical pathway between October 1, 1993 and September 30, 1995 at a university-affiliated DVA medical center were studied retrospectively. After univariate screening of a battery of preoperative risk and intraoperative clinical process variables, stepwise logistic regression was used to determine associations with tracheal extubation < or = 10 h (early) or > 10 h (late) after surgery. Postoperative lengths of stay, complications, and 30-day and 6-month mortality rates were compared between the two groups. RESULTS: One hundred forty-six patients (48.3%) were extubated early; one patient required emergent reintubation (0.7%). Of the preoperative risk variables considered, only age (odds ratio, 1.80 per 10-yr increment) and preoperative intraaortic balloon pump (odds ratio, 7.88) were multivariately associated with time to extubation (model R) ("late" association is indicated by an odds ratio >1.00; "early" association is indicated by an odds ratio <1.00). Entry of these risk variables into a second regression model, followed by univariately significant intraoperative clinical process variables, yielded the following associations (model R-P): age (odds ratio, 1.86 per 10-yr increment), sufentanil dose (odds ratio, 1.54 per 1-microg/kg increment), major inotrope use (odds ratio, 5.73), platelet transfusion (odds ratio, 10.03), use of an arterial graft (odds ratio, 0.32), and fentanyl dose (odds ratio, 1.45 per 10-microg/kg increment). Time of arrival in the intensive care unit after surgery was also significant (odds ratio, 1.42 per 1-h increment). Intraoperative clinical process variables added significantly to model performance (P < 0.001 by the likelihood ratio test). CONCLUSIONS: In this population, early tracheal extubation was accomplished in 48% of patients. Intraoperative clinical process variables are important factors to be considered in the timing of postoperative extubation after fast track cardiac surgery.     

Persistent chorea following cardiac surgery for congenital heart disease

We describe a 6 year old girl with chorea following cardiac surgery, the first such report in Japan. The radical operation for total anomalous pulmonary venous return was carried out at the age of 11 months under hypothermia. Seven days after the operation, a sudden onset of irritability, dysphagia, chorea, generalized, hypotonia, and complete external ophthalmoplegia were seen. These symptoms diminished gradually, but chorea remained. We speculated that the cause of chorea arose from the cardiac surgery under hypothermia. It is necessary to consider 'cardiac surgery' as one of the triggers of certain movement disorders including chorea. We tried treatment with haloperidol, pimozide, and several other drugs; only pimozide was effective in decreasing chorea without any side-effects.     

Self-care and psychosocial adjustment of patients following cardiac surgery

This research examined the role of self-care behavior of 151 patients (aged 40 to 80) on general psychological distress at one year after coronary artery bypass graft (CABG) surgery. A tested hypothesis was that self-care practices would be associated with a lower level of distress one year after surgery. The results supported the beneficial effect of self-care on psychological adjustment, after controlling for the effects of the number of other chronic illnesses and post-CABG depression. The findings suggest that social work in health care and in-home care may help promote the psychosocial recovery process following surgery.     

Unusual left atrial mass following cardiac surgery in an infant

An unexpected left atrial mass was found during routine postoperative transthoracic echocardiogram in an infant following surgical closure of ventricular septal defect. Thrombus could not be excluded. At reoperation it was found to be an inverted left atrial appendage. This case demonstrates the echocardiographic appearance of an inverted left atrial appendage.     

Induced hypothermia in the postoperative management of refractory cardiac failure following paediatric cardiac surgery

Postoperative low cardiac output states are a major cause of postoperative mortality in infants and children following corrective cardiac surgery for congenital heart defects. In this unit, whole body hypothermia has been used since 1979 in the management of these low output states when they are refractory to conventional modes of therapy. Twenty cases treated in this way between July 1986 and June 1990 were reviewed in 1992. The current report reviews the 50 further cases treated with moderate hypothermia between July 1990 and December 1995. The median (range) age of patients was 8 months (0 days-16 years) with a median weight of 4.1 kg (2.5-33 kg). Following cooling, there was a decrease in heart rate (p < 0.001), an increase in mean arterial pressure (p < 0.001) and a decrease in mean atrial pressure (p < 0.001). Significant increases in pH and urine output were also noticed, the increase in urine output being greater in the surviving group (p = 0.02). A decrease in platelet count occurred (p < 0.001) but white blood cell count remained unchanged (p = 0.18). Twenty-five of the 50 patients survived to leave hospital. Induced hypothermia does not appear to be associated with any complications and after the failure of all conventional treatment, it seems likely that the technique may have been beneficial to outcome in some patients.     

Independent association between acute renal failure and mortality following cardiac surgery

With the increasing frequency of surgical operations to the cavernous sinus greater knowledge of the microanatomy of the cavernous sinus has become necessary. The most frequently seen complications during cavernous sinus surgery involve impairment of cranial nerves. This can occur due to direct damage or ischemia. For these reasons, it is important to know the arterial supplies to the cranial nerves in the cavernous sinus and the anatomy of these branches as well. 15 formaline fixed adult cadavers were used in this study. Before the dissections, the internal carotid artery and vertebral artery were filled with coloured latex on both sides. In this report, the intracavernous branches of internal carotid artery (I.I.C.A.) were identified based on the principles of Nomina Anatomica (1989) and compared with others. In our study we found that the segment of the abducens nerve which lies in Dorello's channel was supplied by the meningeal branch; from the point at which it pierces the cerebellar tentorium, the trochlear nerve is supplied by the tentorial cerebellar artery; the posterior cerebellar artery supplies the proximal segment of the oculomotor nerve that proceeds to the oculomotor triangle. Except for these, all the cranial nerves that were located on the lateral wall of the sinus cavernosus are supplied by the tentorial marginal branch and the branches of the lateral trunk.     

The impact of nosocomial infections on patient outcomes following cardiac surgery

STUDY OBJECTIVE: To evaluate the relationship between nosocomial infections and clinical outcomes following cardiac surgery, and to identify risk factors for the development of nosocomial infections in this patient population. DESIGN: Prospective cohort study. SETTING: Barnes-Jewish Hospital, St. Louis, a university-affiliated teaching hospital. PATIENTS: Six hundred five consecutive patients undergoing cardiac surgery. INTERVENTIONS: Prospective patient surveillance and data collection. MAIN OUTCOME MEASURES: Occurrence of nosocomial infections, multiorgan dysfunction, hospital mortality, and risk factors for the acquisition of nosocomial infections. RESULTS: One hundred thirty-one (21.7%) patients acquired at least one nosocomial infection following cardiac surgery. Four independent risk factors for the development of a nosocomial infection were identified: the duration of mechanical ventilation, postoperative empiric antibiotic administration, the duration of urinary tract catheterization, and female gender. Thirty (5.0%) patients died during their hospitalization. The mortality rate of patients acquiring a nosocomial infection (11.5%) was significantly greater than the mortality rate of patients without a nosocomial infection (3.2%) (odds ratio [OR]=4.0; 95% confidence interval [CI]=2.7 to 5.8; p<0.001). Multiorgan dysfunction was found to be the most important independent determinant of hospital mortality (adjusted OR=23.8; 95% CI=13.5 to 42.1; p<0.001) along with the aortic cross-clamp time (adjusted OR=2.3; 95% CI=1.7 to 3.0; p=0.002) and severity of illness as measured by APACHE II (acute physiology and chronic health evaluation) (adjusted OR=1.1; 95% CI=1.1 to 1.2; p=0.019). Ventilator-associated pneumonia, clinical sepsis, female gender, the cardiopulmonary bypass time, and severity of illness were identified as independent risk factors for the development of multiorgan dysfunction. Among hospital survivors, patients acquiring a nosocomial infection had longer hospital lengths of stay compared to patients without a nosocomial infection (20.1+/-13.0 days vs 9.7+/-4.5 days; p<0.001). CONCLUSIONS: Nosocomial infections, which are common following cardiac surgery, are associated with prolonged lengths of hospitalization, the development of multiorgan dysfunction, and increased hospital mortality. These data suggest potential interventions for the prevention of nosocomial infections following cardiac surgery that could substantially improve patient outcomes and decrease medical care costs.     

Effect of anesthetic technique on cardiac morbidity following carotid artery surgery

Clarithromycin and rifabutin are among the most promising drugs for the therapy of infections caused by Mycobacterium avium or other atypical mycobacteria. Since synergism of combined drugs is important in order to achieve strong antimycobacterial activity, the combined inhibitory effects of antibacterial agents should also be investigated when agents are evaluated for possible use in antimycobacterial drug therapy. In the present study we examined the antimycobacterial activity of clarithromycin, rifabutin, and their combination against 51 clinical isolates of the M. avium complex from patients with acquired immune deficiency syndrome (AIDS) with disseminated mycobacteriosis. A concentration-dependent inhibition was seen for each drug. The antibacterial effect was significantly more pronounced for the combined drugs than for the agents tested separately. Synergism, against up to 88% of the strains tested, was seen for the tested drugs combined at different concentrations. All 51 M. avium strains were susceptible to the combination of 4 mg/l clarithromycin and 2 mg/l rifabutin.     

Propofol or midazolam for sedation and early extubation following cardiac surgery

PURPOSE: The purpose of this randomized, double-blind study was to evaluate the efficacy of midazolam and propofol for postoperative sedation and early extubation following cardiac surgery. METHODS: ASA physical status II-III patients scheduled to undergo elective first-time cardiac surgery with an ejection fraction > 45% were eligible. All patients received a standardized sufentanil/isoflurane anaesthesia. During cardiopulmonary bypass 100 micrograms.kg-1.min-1 propofol was substituted for isoflurane. Upon arrival in the Intensive Care Unit (ICU), patients were randomized to either 10 micrograms.kg-1.min-1 propofol (n = 21) or 0.25 microgram.kg-1.min-1 midazolam (n = 20). Infusion rates were adjusted to maintain sedation within a predetermined range (Ramsay 2-4). The infusion was terminated after four hours. Patients were weaned from mechanical ventilation and their tracheas extubated when Haemodynamic stability, haemostasis, normothermia and mental orientation were confirmed. Haemodynamic measurements, arterial blood gas tensions and pulmonary function tests were recorded at specified times. RESULTS: There were no differences between the two groups for the time spent at each level of sedation, number of infusion rate adjustments, amount of analgesic and vasoactive drugs, times to awakening and extubation. The costs of propofol were higher than those of midazolam. There were no differences in haemodynamic values, arterial blood gas tensions and pulmonary function. CONCLUSION: We conclude that midazolam and propofol are safe and effective sedative agents permitting early extubation in this selected cardiac patient population but propofol costs were higher.     

Can clinicians predict ICU length of stay following cardiac surgery?

OBJECTIVES: To assess the effects of smoking during pregnancy on coagulation and fibrinolysis. DESIGN: A cross-sectional study. SETTING: A teaching hospital in Heerlen, The Netherlands. RESULTS: Parameters of coagulation activation increased significantly with gestational age. The values presented are median values. Prothrombin fragment 1 + 2 increased from 0.8 to 2.5 nmol/l in the nonsmoking group of pregnant women and from 1.0 to 1.8 nmol/l in the smoking group. Thrombin-antithrombin III (TAT) levels increased from 2.2 to 9.9 micrograms/l in the nonsmoking group and from 3.1 to 8.5 micrograms/l in the smoking group. Parameters of fibrinolysis showed a different picture. Plasminogen levels in both groups rose significantly in the first half of gestation reaching a plateau in the second half. The alpha 2-antiplasmin levels remained constant in both groups, although the smokers started with significantly higher levels: 119 versus 105% in the nonsmokers. The D-dimer levels rose significantly in both groups: from 278 to 847 micrograms/ml in the nonsmokers and from 215 to 520 micrograms/ml in the smokers. They were significantly lower in the smoking group from the 11th up to the 40th weeks. The D-dimer/TAT ratio was significantly higher in the nonsmokers. CONCLUSIONS: In smoking pregnant women the activated coagulation process was not counter balanced by an adequate increase of fibrinolysis which was the case in the nonsmokers.     

Relationship of preoperative antiendotoxin core antibodies and adverse outcomes following cardiac surgery

This study assesses the reliability of a self-reported health questionnaire completed by 413 subjects aged 25-74 yr in the Erie County Periodontal Disease (ECPD) Study. Specific questions on general and oral health conditions were completed by each subject during a first visit and at a follow-up examination 2 yr later, and the two compared. Results showed that the overall measure of agreement between the two visits is substantial (average kappa, kappa = 0.80). Variation by gender and age were minimal. Questions regarding allergy to medications, oral treatment, reason for tooth extraction, health symptoms and history of systemic diseases exhibited high levels of agreement (kappa ranged from 0.71-0.90). Information on vitamin and mineral intake yielded kappa = 0.63. Oral conditions scored the lowest but were still acceptable (kappa = 0.57). These findings indicate that there were no significant discrepancies in self-reported responses to the health questionnaire used in the ECPD Study. Although the information provided by the subject may not be as accurate as compared to laboratory testing, it is nevertheless a reliable source of information which can be utilized cost-effectively in research studies.     

Effect of residential cardiac rehabilitation following bypass surgery. Observations in Switzerland

BACKGROUND: Cardiac rehabilitation in central Europe traditionally involves isolating patients in a residential idyllic setting where exercise is performed frequently but in a relatively unstructured fashion. Few studies have been performed on the effects of these programs among patients who have undergone bypass surgery. Recent data suggest that postbypass patients may enter these programs too soon after surgery or that exercise is not structured enough to distinguish the benefits of rehabilitation from those experienced by a control group. METHODS: Forty-two male patients (mean age, 58 +/- 7 years) were divided into exercise and control groups approximately 1 month after undergoing bypass surgery. Exercise training consisted of 1 h of group walking twice daily, with the intensity stratified into four levels based on initial exercise capacity. Using a crossover design, patients in the exercise group participated in rehabilitation for 1 month, followed by 1 month of usual care, while control patients underwent the opposite sequence. At 1, 2, and 3 months, patients in both groups underwent pulmonary function testing and maximal ramp exercise testing using lactate and gas exchange analysis. RESULTS: A main effect for maximal oxygen uptake was observed; significant improvements within each group occurred across each testing period (range, 5 to 13%; p < 0.05). However, there was no significant interaction between groups. Mean lactate levels throughout exercise were reduced within both groups (p < 0.01). A reduction in oxygen uptake for test 2 at the lactate threshold in the exercise group resulted in differences between groups in lactate, heart rate, and other gas exchange variables at this point. CONCLUSION: Similar changes occur in the functional status of postbypass surgery patients regardless of their participation in the short but concentrated programs common in central Europe. This suggests that a significant spontaneous effect of healing occurs in the recovery phase after surgery. These programs may have greater efficacy if they began later after surgery, lasted longer, or were more structured, and studies are needed to determine their effect on psychosocial factors and return to work.     

Enoxaparin for unstable angina and ancrod for cardiac surgery following heparin allergy

OBJECTIVE: To describe a patient who presented with heparin allergy and required alternate anticoagulation for unstable angina and coronary artery bypass surgery. To review therapeutic alternatives to porcine heparin for patients with hypersensitivity or intolerance to standard heparin anticoagulation. CASE SUMMARY: A 74-year-old man with a 15-year-old coronary artery bypass graft presented to the emergency room with unstable angina and was scheduled for urgent coronary artery revascularization. A bolus dose of porcine heparin was administered followed by a continuous infusion. Shortly afterward the patient developed a type I allergic reaction to the porcine heparin that was confirmed by rechallenge. Three alternatives to porcine heparin were tried, including bovine lung heparin, low-molecular-weight heparin (enoxaparin), and ancrod. The patient was found to be cross-sensitive to bovine lung heparin, but tolerated enoxaparin for unstable angina without cross-sensitivity. Anticoagulation for cardiopulmonary bypass was achieved with an infusion of ancrod that was later reversed with cryoprecipitate. The patient was discharged postoperatively on day 5 without the complication of excessive bleeding. DISCUSSION: Type I allergic reaction to unfractionated heparin is a rare occurrence and could be the result of a variety of factors. Possible causes for the reaction include a porcine protein, a preservative contained in the heparin solution, or a hapten formed between heparin and a plasma protein. We considered four alternatives to heparin anticoagulation: rush desensitization, bovine lung heparin, low-molecular-weight heparin, and ancrod. The patient was cross-sensitive to bovine lung heparin, but was able to tolerate low-molecular-weight heparin (enoxaparin). This was unexpected because enoxaparin is derived from unfractionated porcine heparin. Testing for cross-sensitivity had no value in this case, as two negative subcutaneous test doses were followed by dramatic reactions when the drugs were given intravenously. Although enoxaparin has been used for anticoagulation during bypass surgery, there is more experience with ancrod as an alternative to heparin. Repeat bypass surgery, which normally results in above-average blood loss, was successfully performed with a very low fibrinogen concentration (< 0.15 g/L) during ancrod anticoagulation. CONCLUSIONS: We conclude that ancrod was a safe and effective alternative to heparin for coronary artery bypass surgery in this patient in whom a heparin product had caused a hypersensitivity reaction. We discovered on two occasions that a negative subcutaneous test dose for heparin allergy did not predict a severe type I allergic reaction when the heparin was later administered intravenously. Furthermore, we found that a low-molecular-weight heparin administered subcutaneously for a short period of time did not cause cross-sensitivity in a patient with a type I allergy to unfractionated heparin.     

Right-sided endocarditis following abortion--underdiagnosed condition case report

We have presented a patient who followed abortion went on to develop septicemia, right-sided endocarditis and septic pulomonary emboil. Such potentially fatal condition should be prevented and diagnosed early to prevent morbidity and mortality.     

Endogenous morphine levels increase following cardiac surgery as part of the antiinflammatory response?

Knowledge about neurotransmitters, their receptors and their physiological effects has exploded in the past 15-20 years. Serotonin exerts diverse effects as a neurotransmitter and in nonneural tissues. The molecular sites of serotonin binding, re-uptake and autoregulation have proven to be viable targets for pharmacological intervention in a variety of disorders.