Biomedical subjects

Charles Weissman

Publications and source records attributed to Charles Weissman.

26 records · Page 2Linked to original sources

PubMed2004

Pulmonary complications after cardiac surgery.

Over the past two decades there has been a steady evolution in the practice of adult cardiac surgery with the introduction of "off-pump" surgery. However, respiratory complications remain a leading cause of postcardiac surgical morbidity and can prolong hospital stays and increase costs. The high incidence of pulmonary complications is in part due to the disruption of normal ventilatory function that is inherent to surgery in the thoracic region. Furthermore, patients undergoing such surgery often have underlying illnesses such as intrinsic lung disease (e.g., chronic obstructive pulmonary disease) and pulmonary dysfunction secondary to cardiac disease (e.g., congestive heart failure) that increase their susceptibility to postoperative respiratory problems. Given that many patients undergoing cardiac surgery are thus susceptiple to pulmonary complications, it is remarkable that more patients do not suffer from them during and after cardiac surgery. This is to a large degree because of advances in anesthetic, surgical and critical care that, for example, have reduced the physiological insults of surgery (e.g., better myocardial preservation techniques) and streamlined care in the immediate postoperative period (e.g., early extubation). Moreover, the development of minimally invasive surgery and nonbypass techniques are further evidence of the attempts at reducing the homeostatic disruptions of cardiac surgery. This review examines the available information on the incidences, consequences, and treatments of postcardiac surgery respiratory complications.

Aged↗

PubMed2004

Multiple casualty terror events: the anesthesiologist's perspective.

UNLABELLED: In a 28-mo period 14 multiple-casualty terror events occurred in Jerusalem, challenging the Department of Anesthesiology and Critical Care Medicine of the city's sole Level 1 trauma center. We performed a retrospective review of the response of the department to evaluate staff activities, resource use (emergency department, operating rooms, and intensive care unit [ICU]), and patient flow. A total of 1062 people were injured in the 14 multi-casualty terror incidents. The emergency department treated 355 victims; 108 of them were hospitalized, and 58 underwent surgery during the first 8 h. Only two surgeries were performed during the first hour, and the average time to the first surgery was 124 min. Fifty-one patients were admitted to the ICU an average of 5.5 h after the terror event. After a terrorist act, multiple, simultaneous efforts were required of the anesthesiology department, including taking part in the initial resuscitation in the emergency department, anesthetizing victims for surgery and angiographies, and caring for them in the recovery room and ICU. Therefore, anesthesiology departments are greatly impacted by such events and must plan for them to maximize the use of available personnel and to have the appropriate equipment and supplies available. IMPLICATIONS: Anesthesiologists provide essential care to patients injured in terror events, from the initial resuscitation through therapeutic/diagnostic procedures and surgeries. Operational issues faced by a department of anesthesiology during the initial 8 h after terrorist actions were examined. Multiple, and often parallel, efforts were required of the department.

Anesthesiology↗

PubMed2003

Association of cardiac troponin, CK-MB, and postoperative myocardial ischemia with long-term survival after major vascular surgery.

OBJECTIVES: The aim of this study was to determine the long-term prognosis with postoperative markers of myocardial ischemia and infarction. BACKGROUND: Cardiac troponins (cTn) are superior to creatine kinase-MB fraction (CK-MB) in detecting perioperative myocardial infarction (PMI). However, their threshold levels signifying PMI and their long-term prognostic value are not yet determined. METHODS: A cohort of 447 consecutive patients who underwent 501 major vascular procedures was prospectively studied. Perioperative continuous 12-lead electrocardiogram monitoring, cardiac troponin-I (cTn-I) and/or cardiac troponin-T (cTn-T), and CK-MB levels on the first three postoperative days, and long-term survival were determined. The association of different cutoff levels of CK-MB, troponin, and ischemia duration with long-term survival was investigated. RESULTS: Between 14 (2.9%) and 107 (23.9%) of the patients sustained PMI, depending on the biochemical criteria used. Elevated postoperative CK-MB, cTn, and prolonged (>30 min) ischemia, at all cutoff levels examined, predicted long-term mortality independent of the preoperative predictors: patient's age, type of vascular surgery, previous myocardial infarction, and renal failure (Cox multivariate analysis). Both CK-MB >10% and cTn-I >1.5 ng/ml and/or cTn-T >0.1 ng/ml independently predicted a 3.75-fold and 2.06-fold increase in long-term mortality (p = 0.006 and 0.012, respectively). Similarly, both CK-MB >5% and cTn-I >0.6 ng/ml and/or cTn-T >0.03 ng/ml independently predicted a 2.15-fold and 1.89-fold increase in mortality (p = 0.018 and 0.01, respectively). Patients with both these markers elevated had a 4.19-fold increase in mortality (p < 0.001). CONCLUSIONS: Postoperative CK-MB and troponin, even at low cutoff levels, are independent and complementary predictors of long-term mortality after major vascular surgery.

Adult↗

PubMed2003

Preoperative thallium scanning, selective coronary revascularization, and long-term survival after major vascular surgery.

BACKGROUND: Ischemia on thallium scanning is a strong predictor of long-term mortality in CAD patients. Whether coronary revascularization (CR) in patients with significant ischemia on preoperative thallium scanning (PTS) improves long-term survival after major vascular surgery has not been determined. METHODS AND RESULTS: The perioperative data, including PTS and subsequent CR in patients with moderate to severe reversible ischemia on PTS, and long-term survival of 502 consecutive patients who underwent 578 major vascular procedures were analyzed retrospectively. Patients with PTS who ultimately did not undergo the planned vascular operation were also studied. Cox regression and propensity score analyses were used to analyze survival. A total of 407 patients (81.1%) had PTS: 221 (54.3%) had no or mild defects (group I); 50 (12.3%) had moderate-severe fixed defects (group II); 62 (15.2%) had moderate-severe reversible ischemia yet did not undergo CR (group III); and 74 (18.2%) had moderate-severe reversible ischemia and subsequent CR by CABG (36) or PTCA (38; group IV). Patients who sustained major complications as a result of the preoperative cardiac workup were included in group IV. By multivariate analysis, age, type of vascular surgery, presence of diabetes, previous myocardial infarction, and moderate-severe ischemia on PTS independently predicted mortality (P=0.001, 0.009, 0.039, 0.006, and 0.029, respectively), and preoperative CR predicted improved survival (OR 0.52, P=0.018). Group IV had better survival than group III even when subdivided according to normal and reduced left ventricular function (OR 0.40 and 0.41, P=0.035 and 0.021, respectively). CONCLUSIONS: Long-term survival after major vascular surgery is significantly improved if patients with moderate-severe ischemia on PTS undergo selective CR.

Aged↗

PubMed2003

Intensive care outflow limitation--frequency, etiology, and impact.

OBJECTIVE: To assess the frequency, causes, and effect of unsuccessful discharge decisions from the ICU. SETTING: An 11-bed general intensive care unit of a 750-bed urban university hospital, tertiary referral center and level one trauma center. DESIGN: A prospective, observational study. PATIENTS: All ICU patients judged appropriate for discharge by the ICU attending physician. MEASUREMENTS AND RESULTS: A total of 856 attempted discharges in 706 patients were analyzed over 16 months. Of these, 703 (82%) were successful within 24 hours. Of the remaining 153 unsuccessful discharges, 51 (33%) were deferred because of medical deterioration, 32 (21%) at the request of the ward physicians or nurses and 70 (46%) because of administrative difficulties (lack of ward bed space or disagreement over admitting service). When compared to patients successfully discharged on the first attempt, those whose discharge was deferred had a significantly longer ICU admission prior to the first discharge attempt (median 4d v 3d, P =.009), and a higher proportion required intermediate care (48% v 26%, P <.001). Both these factors were independently associated with unsuccessful discharge in a logistic regression analysis (OR 1.04, 95%CI 1.02, 1.06, P =.0001, OR 2.05 95%CI 1.30, 3.26, P =.002, respectively). Deferred discharges accounted for 153 days of ICU care (2.6% of the total) and were associated with ICU overflow on 118 days (2% of all ICU days). CONCLUSION: ICU outflow limitation occurs in up to 1 in 6 discharges. It can be due to medical deterioration, level of care issues or administrative problems, and may lead to inefficient use of ICU resources.

Bed Occupancy↗

PubMed2003

Anesthesiologists on ambulances: where do we stand?

PURPOSE OF REVIEW: This manuscript provides a critical review of the literature regarding the staffing of emergency medical services, with particular emphasis on anesthesiologists. RECENT FINDINGS: Significant anesthesiology contributions to prehospital care include introduction of new airway management tools and improved physiological monitoring. Contributions to quality of care include patient benefit in terms of life years gained and a specific reduction in mortality from acute myocardial infarction. Intuitive concepts regarding the advantage of anesthesiologists in intubation mishaps and management of the failed airway have yet to be proven. Personnel limitations may be regional, necessitating local evaluation of anesthesiologist availability to staff ambulances. Since a major part of cost-effectiveness research is performed in the US where only paramedics staff ambulances, insufficient data exist regarding the financial implications of such practice. Burnout may be an important factor for deciding whether anesthesiologists should work in the operating room or ambulances or on an alternate basis. SUMMARY: Further research should be performed to evaluate the clinical and financial implications of staffing ambulances with anesthesiologists or other physicians. Randomized controlled studies using standardized intubation techniques are necessary to examine whether prehospital airway management is improved when delivered by anesthesiologists.

Journal Article↗

PubMed2002

Evaluating intraoperative therapeutic and diagnostic interventions.

UNLABELLED: A cost-conscious health care system requires detailed measures of its activities, including measurements of care provided to perioperative patients. Because there are no scoring systems that quantify the extent of intraoperative care interventions, we developed an intraoperative therapeutic intensity score (I-TIS). Physiological/biochemical monitoring and therapeutic interventions were assigned one to four points on the basis of the resource utilization and/or intensity of care they each reflect. Scoring was performed on actual patients, and the results were compared with ASA classification and surgical complexity. A 78-item scoring system was developed and assessed by using two patient groups. Group 1 (n = 307) entered the postanesthesia care unit (PACU) for short postoperative stays and had an I-TIS of 7.3 +/- 5.0; Group 2 patients (n = 443) were either admitted to the surgical, cardiothoracic, or neurosurgical intensive care units or had extended PACU stays, and they had an I-TIS of 25.2 +/- 12.4 (P < 0.001 versus Group 1). The correlation of I-TIS with the surgical complexity classification was r = 0.77, with ASA base relative value units was r(s) = 0.75, and with the ASA physical status classification was r(s) = 0.49. The score correlated well with surgical complexity and was able to differentiate between the intensity of care during various surgical procedures. IMPLICATIONS: A scoring system to quantify the extent of nonsurgical intraoperative care was developed. The scoring system was validated and correlated well with surgical complexity; it was able to differentiate between the intensity of care provided during various surgical procedures.

Adolescent↗

PubMed2002

Perioperative myocardial ischemia and infarction: identification by continuous 12-lead electrocardiogram with online ST-segment monitoring.

BACKGROUND: Perioperative myocardial ischemia is conventionally monitored using five electrocardiographic leads, with only one precordial lead placed at V5. This is based on studies from more than a decade ago. The authors reassessed this convention by analyzing data obtained from continuous on-line 12-lead electrocardiographic monitoring. METHODS: One hundred eighty-five consecutive patients undergoing vascular surgery were monitored by continuous 12-lead ST-trend analysis during and for 48-72 h after surgery. Cardiac troponin I was measured in the first 3 postoperative days, and cardiac outcome was prospectively recorded. Ischemia was defined as ST deviation, relative to the reference preanesthesia electrocardiogram, of 0.2 mV or more in one lead or 0.1 mV or more in two contiguous leads, lasting more than 10 min. RESULTS: During 11,132 patient-hours of monitoring, 38 patients (20.5%) had 66 transient ischemic events, with all but one denoted by ST-segment depression. Twelve patients (6.5%) sustained postoperative infarction (cardiac troponin I > 3.1 ng/ml). Among the 38 patients with ischemia, lead V3 most frequently (86.8%) demonstrated ischemia, followed by V4 (78.9%) and V5 (65.8%). Among the 12 patients with infarction, V4 was most sensitive to ischemia (83.3%), followed by V3 and V5 (75% each). Combining two precordial leads increased the sensitivity for detecting ischemia (97.4% for V3 + V5 and 92.1% for either V4 + V5 or V3 + V4) and infarction (100% for V4 + V5 or V3 + V5 and 83.3% for V3 + V4). On average, baseline preanesthesia ST was above isoelectric in V1 through V3 and below isoelectric in V5 through V6. Lead V4 was closest to the isoelectric level on the baseline electrocardiogram, rendering it most suitable for ischemia monitoring. CONCLUSIONS: As a single lead, V4 is more sensitive and appropriate than V5 for detecting prolonged postoperative ischemia and infarction. Two precordial leads or more are necessary so as to approach a sensitivity of greater than 95% for detection of perioperative ischemia and infarction.

Anesthesia↗