Yatin Mehta

Device-Associated Nosocomial Infections in 55 Intensive Care Units of 8 Developing Countries

Context We know little about medical deviceassociated infections in developing countries. Contribution Prospective surveillance of 21069 patients who were hospitalized in 55 intensive care units in 46 hospitals in Central and South America, India, Morocco, and Turkey showed high rates (22.5 infections per 1000 intensive care unit days) of device-associated infections. Infections included ventilator-associated pneumonia (24.1 cases/1000 ventilator days), central venous catheterrelated bloodstream infections (12.5 cases/1000 catheter days), and catheter-associated urinary tract infections (8.9 cases/1000 catheter days). Eighty-four percent of Staphylococcus aureus infections were caused by methicillin-resistant strains, 51% of Enterobacteriaceae isolates were ceftriaxone-resistant, and 59% of Pseudomonas aeruginosa isolates were fluoroquinolone-resistant. Implications Medical deviceassociated infections pose major risks in developing countries. The Editors Surveillance of health careassociated infections, especially in high-risk hospital settings, such as the intensive care unit (ICU) (1, 2), has become an integral feature of infection control and quality assurance in all U.S. hospitals. The Centers for Disease Control and Prevention (CDC) Study of the Efficacy of Nosocomial Infection Control (SENIC) Project (3) showed that surveillance can help prevent health careassociated infections. Standards for institutional surveillance have been adopted in the United States (1), the United Kingdom (4), Australia (5), Canada (6), and Germany (7). A growing body of literature has shown that health careassociated infections are a major cause of patient illness and death in developed countries (8, 9). Device-associated infections, particularly ventilator-associated pneumonia (1012), central venous catheter (CVC)associated bloodstream infections (1315), and catheter-associated urinary tract infections (16, 17), pose the greatest threat to patient safety in the ICU (18). Surveillance of health careassociated infection has been standardized by the CDCs National Nosocomial Infection Surveillance (NNIS) System by providing simple unambiguous definitions, especially for device-associated infections (1921). Targeted surveillance and calculation of device-associated infection rates per 1000 device days allows benchmarking with similar other hospitals and detection of unique institutional problems that need redress. Most published studies of ICU-acquired infections have come from hospitals in industrialized western countries (1, 8, 1019, 22, 23). Relatively few data have been reported from developing countries (9, 2427), especially rates of device-associated infections by using standardized definitions. We report the initial findings of an International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2002 through December 2005. The consortium was established by Dr. Rosenthal in 1998 when selected hospitals in Latin America began collecting surveillance data on health careassociated infections for inclusion in a regional database. Consortium hospitals provide general medical and surgical inpatient services to adults and children who require short-term care. All data from the participating hospitals were collected by using standardized NNIS System protocols and definitions (1921). The consortium has initially focused on surveillance and prevention of device-associated infections in adult and pediatric ICUs and high-risk nurseries. Methods Setting Most current participating hospitals and ICUs joined the consortium since 2002 after hearing Dr. Rosenthal (the INICC chairman) speak in their country or after learning about the INICC from its Web site (www.inicc.org), but some hospitals were actively solicited. Study data were collected between 2002 and 2005 in 55 ICUs in 46 hospitals from 8 developing countries: Argentina, Brazil, Colombia, India, Mexico, Morocco, Peru, and Turkey. The consortium requires each member hospital to have an infection control team, comprising a physician and an infection control practitioner, and a microbiology laboratory that can isolate and identify aerobic pathogens from clinical cultures and perform in vitro susceptibility testing by using standardized methods (28). The person responsible for surveillance in each institution must have had at least 3 years of infection control experience (Table 1). In most of the hospitals, the team had access to electronic patient data. Table 1. Features of the International Nosocomial Infection Control Consortium Hospitals and Intensive Care Units* The institutional review board at each hospital approved the study protocol. Patient confidentiality is protected by coding the recorded information, with patient identities available only to the individual hospitals infection control team. Infection Control Practices at the Study Sites Hand hygiene adherence varies in the different countries and ICUs, ranging from 20% to 70% (2932). A recent study in all participating ICUs found a 50% overall rate of hand hygiene adherence (32), similar to that of recent studies in the United States and Europe (33). Use of sterile dressings on CVC insertion sites also ranges widely (29, 34, 35). Open infusion systems (rigid or semirigid containers that must admit air to empty) rather than closed systems (fully collapsible containers that do not require any external vent to empty the solution; the container residue after administration does not exceed 5% of the nominal volume) or combinations of open and closed systems are universally used to deliver intravenous fluids and medications in the study hospitals (35). Surveillance and Case Report Forms Each center established an augmented infection control program, with the initial major emphasis on active surveillance of health careassociated infections and process surveillance of hand hygiene adherence and invasive device care. During the study, we determined the rates of ventilator-associated pneumonia, CVC-associated bloodstream infection, and catheter-associated urinary tract infection monthly by using current CDC NNIS System definitions (1921). Designated surveillance forms were used for all patients in the study ICUs, both patients with and those without health careassociated infection. The following data were to be recorded daily on the forms for each patient: temperature and blood pressure, invasive devices, all cultures done, imaging studies, and antibiotic use. Previous studies have shown that fever, hypotension, cultures, and initiation of antimicrobial therapy are powerful markers for the presence of a health careassociated infection (36). A mean average severity of illness score was also recorded for each patient at ICU admission by using the CDC NNIS System criteria (19). Points were totaled, with 1 point for surgical patients who require routine postoperative observation only, 2 points for physiologically stable nonsurgical patients who require overnight observation, 3 points for patients who need continuous nursing care and monitoring, 4 points for physiologically unstable patients who require intensive nursing and medical care and need frequent reassessment and adjustment of therapy, and 5 points for physiologically unstable patients who are in a coma or in shock and require cardiopulmonary resuscitation or intensive medical and nursing care with frequent reassessment. If a patient was determined to have acquired a health careassociated infection, the date of onset, site of infection, infecting microorganisms, and antimicrobial susceptibilities were also recorded. Definitions Ventilator-Associated Pneumonia Ventilator-associated pneumonia is indicated in a mechanically ventilated patient with a chest radiograph that shows new or progressive infiltrates, consolidation, cavitation, or pleural effusion. The patient must also have at least 1 of the following criteria: new onset of purulent sputum or change in character of sputum; organism cultured from blood; or isolation of an etiologic agent from a specimen obtained by tracheal aspirate, bronchial brushing or bronchoalveolar lavage, or biopsy. Laboratory-Confirmed CVC-Associated Bloodstream Infection Central venous catheterassociated bloodstream infection is laboratory-confirmed when a patient with a CVC has a recognized pathogen that is isolated from 1 or more percutaneous blood cultures after 48 hours of vascular catheterization and is not related to an infection at another site. The patient also has at least 1 of the following signs or symptoms: fever (temperature 38C), chills, or hypotension. With skin commensals (for example, diphtheroids, Bacillus spp., Propionibacterium spp., coagulase-negative staphylococci, or micrococci), the organism is cultured from 2 or more blood cultures. Clinically Suspected CVC-Associated Bloodstream Infection Central venous catheterassociated bloodstream infection is clinically suspected when a patient with a CVC has at least 1 of the following clinical signs with no other identified cause: fever (temperature 38C), hypotension (systolic blood pressure 90 mm Hg), or oliguria (urine output 20 mL/h) with blood cultures not obtained or no organisms recovered from blood cultures, infections not apparent at another site, and antimicrobial therapy instituted by the physician. Catheter-Associated Urinary Tract Infection For the diagnosis of catheter-associated urinary tract infection, the patient must meet 1 of 2 criteria. The first criterion is when a patient with a urinary catheter has 1 or more of the following symptoms with no other recognized cause: fever (temperature 38C), urgency, or suprapubic tenderness when the urine culture is positive for 105 colony-forming units per mL or more, with no more than 2 microorganisms isolated. The second criterion is when a patient with a urinary catheter has at least 2 of the following criteria with no other recognized cause: positive dipstick analysis for leukocyte esterase or nitr

Cardiac output monitoring: comparison of a new arterial pressure waveform analysis to the bolus thermodilution technique in patients undergoing off-pump coronary artery bypass surgery.

OBJECTIVE To analyze the clinical agreement between the conventional intermittent bolus thermodilution (TD) technique and a new arterial pressure waveform analysis (APCO) technique (FloTrac; Edward Lifesciences, Irvine, CA) for cardiac output (CO) estimation. DESIGN Prospective observational clinical study. SETTING Cardiac surgery operating room of a tertiary care cardiac center. PARTICIPANTS Twelve patients undergoing elective off-pump coronary artery bypass (OPCAB) surgery. MEASUREMENTS AND MAIN RESULTS CO was determined by 2 different methods: TD and APCO at 8 time points (preinduction, postinduction, poststernotomy, left internal mammary artery to left anterior descending artery anastomosis, left [obtuse marginal/diagonal] anastomosis, right [right coronary/posterior descending coronary artery] anastomosis, postprotamine administration, and poststernal closure) in 12 patients undergoing elective OPCAB surgery. The mean bias and limits of agreement (2 standard deviations) expressed in liters per minute at respective points of measurement were -0.54 +/- 1.12, -0.37 +/- 1.0, -0.42 +/- 1.50, -0.25 +/- 1.18, -0.31 + 1.28, +/-0.41 +/- 1.0, 0.06 +/- 1.50, and 0.09 +/- 1.40. CONCLUSION Good agreement was found between the CO values obtained by the APCO and TD techniques throughout the intraoperative period including the period of coronary artery graft surgery.

A comparative evaluation of intrapleural and thoracic epidural analgesia for postoperative pain relief after minimally invasive direct coronary artery bypass surgery

OBJECTIVE To compare the efficacy of thoracic epidural analgesia (TEA) and intrapleural analgesia (IPA) after minimally invasive direct coronary artery bypass (MIDCAB) surgery with regard to quality of analgesia and complications. DESIGN A prospective, randomized study. SETTING A specialty research hospital. PARTICIPANTS Fifty consenting adults scheduled for MIDCAB surgery. INTERVENTIONS All patients underwent elective MIDCAB surgery. Patients in the TEA group (n=25) had an epidural catheter inserted in the fourth to fifth thoracic interspace and those in the IPA group (n=25) had an intrapleural catheter inserted in the sixth to seventh intercostal space intraoperatively under vision. MEASUREMENTS AND MAIN RESULTS Parameters evaluated after administration of bupivacaine (8 mL of 0.25% in the TEA group and 20 mL of 0.25% in the IPA group) on first demand included visual analog scale (VAS) pain scores, cardiovascular and respiratory (clinical, blood gases) function, wakefulness, supplemental analgesic requirement, and complications. Measurements were made at 2-hour intervals for the next 12 hours. VAS scores were significantly lower at 2, 6, 8, and 12 hours in the IPA group (TEA = 3.5, 4.5, 4.9, 4.6; IPA = 2.2, 3.6, 3.5, 3.7). There were no significant differences in hemodynamic or respiratory parameters or postoperative requirement for supplemental analgesia. In the TEA group, three patients had catheter migration and four had severe backache. CONCLUSION IPA is a safe and effective technique for postoperative analgesia after MIDCAB surgery and has a low complication rate compared with TEA. Careful positioning, chest tube clamping, and anchoring of the catheter are mandatory for IPA to be effective.

Comparison of continuous thoracic epidural and paravertebral block for postoperative analgesia after robotic-assisted coronary artery bypass surgery

Minimally invasive surgery with robotic assistance should elicit minimal pain. Regional analgesic techniques have shown excellent analgesia after thoracotomy. Thus the aim of this study was to compare thoracic epidural analgesia (TEA) technique with paravertebral block (PVB) technique in these patients with regard to quality of analgesia, complications, and haemodynamic and respiratory parameters. This was a prospective randomised study involving 36 patients undergoing elective robotic-assisted coronary artery bypass grafting (CABG). TEA or PVB were administered in these patients. The results revealed no significant differences with regard to demographics, haemodynamics, and arterial blood gases. Pulmonary functions were better maintained in PVB group postoperatively; however, this was statistically insignificant. The quality of analgesia was also comparable in both the groups. We conclude that PVB is a safe and effective technique for postoperative analgesia after robotic-assisted CABG and is comparable to TEA with regard to quality of analgesia.

Total Intravenous Anesthesia With Ketamine for Pediatric Interventional Cardiac Procedures

OBJECTIVE To evaluate the safety and efficacy of ketamine in pediatric patients undergoing interventional cardiac procedures. DESIGN A retrospective clinical study. SETTING A single, tertiary referral center. PARTICIPANTS Patients (n = 107) undergoing interventional cardiac procedures between July 1996 and July 1998. INTERVENTIONS Each patient received a bolus of ketamine, 1 mg/kg intravenously, followed by an infusion of 50 to 75 microg/kg/min for the duration of the procedure. MEASUREMENTS AND MAIN RESULTS Hemodynamic and respiratory parameters were noted. All patients were breathing spontaneously. Average infusion dose of ketamine was 51.40+/-3.54 microg/kg/min (mean +/- standard deviation). Increases in heart rate and mean arterial pressure by more than 20% from baseline values were seen in 10 and 9 patients, respectively. Transient apnea and excessive salivation were seen in two patients each. Excessive movement of extremities was seen in six patients. There were no episodes of unpleasant dreams or hallucinations. There were two deaths (1.9%) related to the interventional procedures. CONCLUSION The technique described is a simple, safe, and effective method for anesthetizing children in the cardiac catheterization laboratory for interventional procedures.

Ten-year experience with single-vessel and multivessel reoperative off-pump coronary artery bypass grafting

OBJECTIVE Patients undergoing reoperative coronary artery bypass have increased mortality and morbidity compared with those undergoing primary coronary bypass. The experience in applying off-pump techniques to coronary reoperations is limited. In this article we report a 10-year experience using various techniques of reoperative off-pump coronary bypass. METHODS Between January 1996 and December 2005, 332 patients underwent reoperative off-pump coronary artery bypass grafting. Data were collected regarding the preoperative, intraoperative, and postoperative clinical course of all patients. These were compared with similar data obtained from patients who had undergone conventional coronary reoperation during this period. RESULTS Two hundred ninety-six (89.2%) male and 36 female patients underwent reoperative off-pump coronary artery bypass. Of these, 265 (79.8%) patients underwent multivessel bypass through a median sternotomy, an anterolateral thoracotomy was performed in 63 (19%) patients, and a posterolateral thoracotomy was performed in 4 (1.2%) patients. The early mortality for patients undergoing off-pump surgery was lower than for those undergoing conventional reoperations (3.3% vs 5.5%, P = .066). Those who had undergone off-pump reoperations had less need for prolonged ventilation or prolonged inotropic support and had shorter intensive care unit and hospital stays than patients who had undergone redo coronary artery bypass grafting. CONCLUSION For many patients requiring coronary reoperations, off-pump techniques are safe and feasible. Complete revascularization was achieved in at least 75% of patients in an unselected population, with mortality and perioperative event rates that are comparable with those of conventionally performed coronary reoperations.

Minimally invasive mitral valve surgery through right anterolateral minithoracotomy

BACKGROUND This study evaluates the feasibility of minimally invasive mitral valve surgery. The aim of the study was to minimize surgical access to achieve better cosmetic results, less postoperative discomfort, and faster recovery. METHODS From September 1997 to October 1998, 76 patients underwent mitral valve surgery through a right anterolateral minithoracotomy at the fourth intercostal space. The mitral valve was either repaired (n = 21) or replaced (n = 55). In all cases, open femoral artery-femoral vein cannulation was used for cardiopulmonary bypass. In 27 cases, an endoluminal aortic clamp was used, but in 49 cases, the aorta was cross-clamped with a transthoracic, sliding-rod-design clamp. RESULTS There were no approach-related limitations to surgical intervention. Intraoperative transesophageal echocardiography revealed excellent results after valve repair and no paravalvular leak in any patient after mitral valve replacement. Mean duration of intensive care and postoperative hospital stay was 32+/-5.2 hours and 7+/-1.1 days, respectively. There were no major complications related to femoral vessel cannulation. In 1 patient, transient neurological problems developed, with subsequent complete recovery. There was one hospital mortality (85-year-old male patient died of upper GI bleeding). CONCLUSIONS Minimally invasive port access mitral valve surgery can accelerate recovery and decrease pain, while maintaining overall surgical efficacy. It also provides better cosmetic results to our patients, and now it has become our standard approach for isolated mitral valve surgery.

Off-pump redo coronary artery bypass grafting

BACKGROUND Conventional redo coronary artery bypass grafting is associated with significant morbidity. The danger of reoperation is mainly in reopening the sternum and in the manipulation of the heart and the old grafts. Therefore, off-pump redo coronary artery bypass grafting with a patient-specific approach in selected cases seems an ideal technique. METHODS Between October 1995 to September 1999, 50 patients with mean age of 61.8+/-8 years underwent reoperative coronary artery bypass grafting without cardiopulmonary bypass. Isolated left internal mammary artery (LIMA) to left anterior descending artery (LAD) anastomosis was carried out in 25 cases through left anterior minithoracotomy. In 1 patient LIMA was grafted on a previous vein graft to LAD, which was critically stenosed proximally but distal anastomosis was patent. In another case LIMA was grafted to Ramus intermedius branch. Midsternotomy approach was used to carry out LAD and right coronary artery grafting in 21 cases. In 2 patients a posterolateral thoracotomy approach was used to bypass obtuse marginal branches without cardiopulmonary bypass; in these cases proximal anastomosis was performed on the descending aorta. RESULTS Mortality rate was 4% (2 deaths). Two patients sustained perioperative myocardial infarction. No patient was reexplored for hemorrhage and 38 patients did not require homologous blood transfusion. Sixteen patients underwent check angiogram and all of them were found to have patent redo grafts. Cardiac recovery room stay was 22+/-7 hours and hospital stay 5+/-2 days. CONCLUSIONS In selected patients, reoperative coronary artery bypass grafting can be performed without cardiopulmonary bypass with a low perioperative morbidity and mortality and satisfactory graft patency.

Transmyocardial laser as an adjunct to minimally invasive CABG for complete myocardial revascularization

BACKGROUND To achieve complete myocardial revascularization in patients with diffuse coronary artery disease and patients at high risk if they undergo cardiopulmonary bypass such as severe systemic disease or diffuse arteriosclerosis of the aorta, we have adopted the technique of combining direct coronary artery bypass grafting without cardiopulmonary bypass with transmyocardial laser revascularization. METHODS From April 1995 to September 1997 this technique was used in 77 patients. Ages ranged from 37 to 85 years with a mean of 56 +/- 17 years. Diffuse coronary artery lesions were present in 46 patients, 10 had severely deranged renal function, 7 had diffuse carotid artery lesions, and 7 had aortic arch atheromas. Liver dysfunction was present in 4 patients and severe obstructive airway disease in 3. The mean left ventricular ejection fraction was 0.45 +/- 0.05. Midsternotomy approach was used in 65 patients and anterior minithoracotomy in 12. Direct coronary artery bypass grafting without cardiopulmonary bypass was done to the left anterior descending coronary artery or right coronary artery or both. Transmyocardial laser revascularization using a 1,000-W CO2 laser machine was performed on the areas supplied by ungraftable coronary arteries or even in graftable distal targets in the posterolateral or inferior wall in patients who were at high risk if they underwent cardiopulmonary bypass. RESULTS The mean number of vessels bypassed was 1.12. One patient died of intractable ventricular arrhythmia in the early postoperative phase. Mean follow-up was 16.6 months. At 12 months 89% of the patients were angina free. Metabolic stress test demonstrated an average increase in exercise tolerance from 5.2 at baseline to 9.7 minutes at 12 months. Myocardial thallium scanning done at 3-, 6-, and 12-month intervals postoperatively revealed that myocardial perfusion in grafted segments had an exponential trend of improvement, and perfusion in transmyocardial laser revascularization segments showed a linear trend in the same period with a total gain of 28.4%. CONCLUSIONS Transmyocardial laser revascularization is an excellent adjunct to minimally invasive coronary artery bypass grafting to achieve complete myocardial revascularization in patients with graftable vessels in the anterior wall and ungraftable vessels in the posterior and inferior wall. This achieves complete myocardial revascularization without compromising safety in patients who are at high risk if they undergo cardiopulmonary bypass. Minimal morbidity and mortality in the present series revealed that this procedure is safe, and postoperative follow-up of these patients showed significant functional improvement as well as an improvement in myocardial perfusion scan.

Cardioprotective effects of diltiazem infusion in the perioperative period.

OBJECTIVE To evaluate the perioperative effects of intravenous diltiazem infusion on left ventricular functions, hemodynamics and as an anti-ischemic and antiarrhythmic agent in patients undergoing coronary artery bypass grafting (CABG). METHODS A double blind, randomised study was performed on 71 patients undergoing elective CABG. Infusion of diltiazem (0.1 mg/kg per h, n = 34) or nitroglycerin (1 microgram/kg per min, n = 37) was given for 24 h starting from onset of cardiopulmonary bypass. Holter monitoring, electrocardiogram and serum cardiac enzymes levels were used to diagnose myocardial ischemia. Myocardial function was assessed by perioperative transesophageal echocardiography. RESULTS The two groups did not differ with respect to preoperative and operative data. Diltiazem had no influence on hemodynamic parameters except for significant reduction in post operative heart rate and pulse pressure rate. Transient ischemic events (dilitiazem 10.2% versus nitroglycerin 33.3%, P = 0.15) and transient coronary spasm (diltiazem-6.8% versus nitroglycerin 25.9%, P = 0.15) were reduced in the diltiazem group as compared with the nitroglycerin group. The postoperative incidence of atrial fibrillation (diltiazem 3% versus nitroglycerin 22%, P = 0.03), supra ventricular tachycardia (diltiazem-3% versus nitroglycerin-22%, P = 0.03) and average ventricular premature contraction per h (diltiazem-40.2 +/- 10.2 versus nitroglycerin 53.8 +/- 12.3, P < 0.01) were significantly lower in the diltiazem group. Transesophageal echocardiography showed no significant difference in left ventricular functions and better preservation of left ventricular diastolic functions in post cardiopulmonary bypass period in diltiazem group. In addition mean deceleration time for the E wave on a 12 h post cardiopulmonary bypass period was significantly lower in the diltiazem group as compared with nitroglycerin (diltiazem 131 +/- 6 versus nitroglycerin 171 +/- 6, P < 0.01). CONCLUSION The present study demonstrates that diltiazem infusion provides superior anti-ischemic protection and control of supraventricular arrhythmias as compared to nitroglycerin and does not produce any negative inotropic effect, as demonstrated by transesophageal echocardiography.