Ibrahim S. Farid

Implementing ACC/AHA guidelines for the preoperative management of patients with coronary artery disease scheduled for noncardiac surgery: effect on perioperative outcome

STUDY OBJECTIVE To review the new consensus guidelines for cardiac testing for the patient with cardiac disease scheduled for elective, noncardiac surgery, and their impact on cardiac functional testing. DESIGN Retrospective chart review study. SETTING Tertiary care medical center. PATIENTS 181 patients scheduled for elective, major surgery who met American College of Cardiology/American Heart Association (ACC/AHA) criteria for a preoperative stress test. INTERVENTIONS A variety of tests were ordered, including treadmill stress testing, persantine-thallium imaging, dobutamine echocardiography, and exercise stress echocardiography. MEASUREMENTS The numbers of and outcome of the stress tests and the cardiac outcome of the patients who underwent cardiac testing and surgery were recorded. MAIN RESULTS Abnormal tests occurred in 27 patients. Two patients declined treatment, eight patients had primary medical management, and the remainder (17) had cardiac catheterization. Results included no lesion (2 patients), angioplasty (4 patients), angioplasty plus stenting (1 patient), coronary artery bypass grafting (CABG) (4 patients), and delineated lesions treated with medical optimization (6 patients). One patient had CABG and declined further surgery. One patient had myocardial infarction 6 months after surgery that was treated by medical management after cardiac catheterization. The other 23 patients had surgery without cardiac complication within 1 year of surgery. Only 15% (27/180) of the patients with indications for a stress test had a positive result. Even fewer patients had any alteration of the perioperative period. Despite this finding, cardiac morbidity was very low. CONCLUSIONS The guidelines for stress test may be over-sensitive, and further prospective clinical studies are indicated.

Diverticulum of kommerell: A review of a series and a report of a case with tracheal deviation compromising single lung ventilation

IMPLICATIONS Birth defects can affect the great vessels of the aorta and its branches, compressing the upper airway and the swallowing track. Surgical repair of these defects requires manipulating the airway to improve surgical exposure. This is a report of a series of cases with compromised airway resulting from such a birth defect and methods of its management.

Intrathecal local anesthetic infusion as a treatment for complex regional pain syndrome in a child.

Diagnosis and treatment of complex regional pain syndrome in children is one of the most challenging clinical pain problems encountered in the chronic pain setting. Despite the intense and debilitating nature of the pain, referral to appropriate specialists often comes too late, thereby prolonging an already arduous (and controversial) course of treatment and risking long-term disability. On the contrary, full recovery can be expected with early diagnosis and prompt treatment. The following case study describes a novel and successful use of intrathecal catheter administration of ropivacaine in a child with early, rapidly progressing, and debilitating complex regional pain syndrome.

Bupivacaine induces transient neurological symptoms after subarachnoid block.

Abstract: Bupivacaine is a long‐acting amide local anesthetic that was introduced to clinical practice in the early 1980s. Since then it has been extensively used for both peripheral blocks as well as neuraxial blockade in concentrations varying from 0.125% to 0.75%. Despite the relatively narrow safety margin, bupivacaine has become the most frequently used local anesthetic in obstetric anesthesia. 1 It is 95% metabolized in the liver and 5% excreted unchanged in urine. 2 Bupivacaine cardiotoxicity is related to the total dose rather than to the concentration of bupivacaine administere. 3 It produces a dose‐dependent delay in the transmission of impulses through the cardiac conduction system by blocking sodium channels. 4 Transient neurologic symptoms (TNS) defined as bilateral symmetrical pain in the lower back and buttocks with radiation to both lower extremities after 5% lidocaine spinal anesthetic was first described by Schneider in 1993. 7 Several studies have failed to show TNS after spinal anesthesia using bupivacaine 0.5% or 0.75%. 8,9 In the literature there is only 1 case report 10 of TNS after spinal anesthesia using bupivacaine and morphine. The following report describes a case of TNS following spinal anesthesia with bupivacaine 0.75%.

Cardiac testing for noncardiac surgery: past, present, and future

The evaluation of risk is a fundamental part of the role of the anesthesiologist in the perioperative period. For elective surgery, this evaluation begins with identification of correctable elements of co-morbidity and appropriate intervention to reduce risk and/or improve outcome. Optimum anesthetic care requires a balance between sensitive detection of risk and cost-effective utilization of expensive resources. The preparation of the patient with known cardiovascular disease for noncardiac surgery is an excellent example of this dilemma. Formal risk-stratification has been a regular part of the daily practice of anesthesiology since the 1960s, with the assignment of an American Society of Anesthesiologists (ASA) physical status classification as a part of every anesthetic administered. Sponsored by the ASA and published by Dripps et al., ASA physical status assignment was designed to predict risk. Subsequent large-scale reviews have shown ASA physical status classifications to correlate with the incidence of major morbidity and mortality, although not in a manner that lends itself to predicting specific cardiac risk, or guiding cardiac testing for elective surgery. The desire to identify a means to predict perioperative cardiac risk has been driven by the observation that adverse cardiac events correlate with certain kinds of surgery, including carotid artery surgery, aortic aneurysm repair, and peripheral revascularization procedures. Recognizing that vascular surgery was highly associated with adverse cardiac events, Hertzer et al. advocated routine cardiac catheterization before vascular surgery, and achieved a very low mortality after major aortic surgery. Subsequent review of this approach revealed normal coronaries in only 8% of more than 1,000 patients scheduled for peripheral vascular surgery, with a significant incidence (14%) with severe correctable coronary artery disease that was not suspected by the clinical history. Coronary angiography led to coronary artery bypass graft procedures in 130 patients in this series who subsequently underwent aortic surgery, with less than 1% mortality. Screening with routine cardiac catheterization did not expand from these studies into a general risk prediction strategy due to the cost and morbidity associated with the procedures. Other approaches have included routine screening with exercise stress testing, dipyridamole-thallium imaging, and dobutamine stress echocardiography. Although some data are supportive, routine screening ultimately proves less than ideal for preoperative preparation for large populations of patients due to risk, cost, and logistics. In an attempt to combine patient factors with surgical issues, Goldman et al.

Diagnosis and management of transient neurologic symptoms following subarachnoid block with single-shot isobaric 2% lidocaine

Hyperbaric 5% lidocaine has been used extensively for spinal anesthesia for the last 50 yr. The implication of lidocaine as specifically etiologic for transient neurologic symptoms (TNS) has led to increasing focus on lidocaine spinal anesthesia and reports of TNS with single-shot, hyperbaric lidocaine. We report the details of a case of TNS associated with single-shot, isobaric 2% lidocaine in a 69-year-old female, scheduled for outpatient hysteroscopy, dilatation and curettage, and endometrial biopsy while placed in the lithotomy position.