American Society of Anesthesiologists, Oct. 17-21, 2009Last Updated: October 28, 2009.
The 2009 Annual Meeting of the American Society of Anesthesiologists took place October 17 to 21 in New Orleans. Over 16,000 attendees were expected at this year's meeting, many of whom were international participants, including professionals, researchers, and specialists presenting the latest scientific and clinical findings in the field of anesthesiology. Nearly 2000 research abstracts were included at this year's meeting.
Amanda A. Fox, M.D., of Brigham and Women's Hospital in Boston, reported clinical study results showing that preoperative levels of B-type natriuretic peptide (BNP) may more reliably predict duration of hospital stay and mortality than postoperative levels of the biomarker following primary coronary artery bypass graft surgery (CABG). BNP, which is secreted primarily by the ventricular chambers of the heart upon stretching, is an already established biomarker for heart failure. A total of 1183 patients were evaluated for both preoperative and postoperative levels of BNP in this prospective longitudinal study, and followed for a mean of approximately four years. During this time, the mortality rate, defined as all deaths occurring within five years after surgery, was 9.7 percent overall. When considered with other clinical risk factors, both preoperative and postoperative BNP levels were independent predictors of both mortality and hospital length of stay. After both clinical risk factors and postoperative BNP levels were accounted for, preoperative BNP remained an independent predictor of duration of hospital stay.
In a statement, Fox suggested that "when preoperative and postoperative BNP measurements are considered together along with clinical risk factors for negative outcomes after CABG surgery, preoperative BNP appears to be the more reliable predictor of longer hospital stay and all-cause mortality. However, it may be that when cardiac specific outcomes such as development of longer term postoperative heart failure are assessed in future studies, postoperative BNP will be better able to capture the likelihood of developing those events."
Craig T. Hartrick, M.D., of the Oakland University William Beaumont School of Medicine in Rochester, Mich., shared results of a study showing that multiple factors must be considered when developing and conducting studies that attempt to predict the development of persistent pain. The study evaluated 58 patients who underwent minor arthroscopic shoulder surgery for rotator cuff repair, which is typically associated with little postoperative pain. Patients still experiencing pain at three months following surgery were matched with patients who had recovered from surgery uneventfully. Patients were evaluated to determine if they were carriers of genes that better controlled the release of catechol-O-methyl transferase (COMT), an enzyme typically associated with protection from the development of temporomandibular joint dysfunction (TMJ) and other forms of pain. Interestingly, patients in the low-pain-sensitivity COMT group experienced the highest levels of pain at three months. Higher anxiety prior to surgery also was associated with increased postoperative pain.
Study co-author, Doug Wendell, Ph.D., also of Oakland University, commented that, "while this study did not confirm an association between anxiety and COMT type, such an association could explain the apparent paradox in our findings and thus may represent an important confounder affecting pain assessments and pain studies that examine the genetic role of COMT."
Henrik Kehlet, M.D., of Copenhagen University in Denmark, presented findings from a study examining factors which had the potential to predispose a patient to persistent postoperative pain. A total of 19 risk factors were investigated in 463 adult male patients following primary groin hernia repair surgery. A questionnaire was used prior to surgery to establish data on hernia-related pain, as well as other patient characteristics. Patients underwent either open Lichtenstein mesh repair or a laparoscopic procedure. After six months, twice as many patients who underwent the more invasive mesh repair procedure experienced pain affecting daily activities compared with patients who underwent the laparoscopic procedure (16 versus 8 percent). Four factors independently predictive of the development of persistent postoperative pain were found to be pain impairment of daily activities prior to surgery, high pain response to heat stimulation prior to surgery, high pain intensity reported 30 days after surgery, and symptoms of nerve injury.
In a statement, Kehlet concluded that "these findings prove that persistent pain following surgery is related to both surgical and patient-specific factors, suggesting that patients with high pain response before surgery should be operated laparoscopically -- a procedure that is less likely to inflict nerve damage and resulting further pain development."
Marek Brzezinski, M.D., of the San Francisco VA Medical Center, reported findings from a retrospective epidemiological study which suggested that post-traumatic stress disorder (PTSD) may affect post-surgery mortality in veterans. A total of 1792 male veterans were included in the study, of which 129 had a diagnosis of PTSD by the day of surgery. PTSD patients were significantly more likely to be younger and to have an increased prevalence of cardiac risk factors. However, despite their younger age, PTSD patients had a 25 percent higher mortality rate one-year following surgery compared to their veteran counterparts without PTSD (8.5 versus 6.8 percent). Even when taking into account patient age and pre-existing medical conditions, veterans with PTSD were 2.2-fold more likely to die within one year following surgery.
According to a statement by Brzezinski, this study "exposes the need to consider potential treatments to help reduce risk in the veteran PTSD population. The number of veterans returning from our current conflicts with PTSD who require surgical treatment is expected to increase in the future."
ASA: Study Finds Benefit From Treatment Before Extubation
THURSDAY, Oct. 22 (HealthDay News) -- The use of dexmedetomidine may be useful in helping wean agitated patients from mechanical ventilation, according to research presented at the annual meeting of the American Society of Anesthesiologists, held from Oct. 17 to 21 in New Orleans.
ASA: Studies Examine Urinary Biomarkers of Kidney Disease
WEDNESDAY, Oct. 21 (HealthDay News) -- The biomarker neutrophil gelatinase-associated lipocalin (NGAL) may best identify acute kidney injury in cardiac surgery patients with normal preoperative kidney function, and undetected kidney cancer may influence urine concentrations of another biomarker, kidney injury molecule-1 (KIM-1), according to research presented at the annual meeting of the American Society of Anesthesiologists, held from Oct. 17 to 21 in New Orleans.
ASA: IV Dextrose Found to Ease Postoperative Nausea
TUESDAY, Oct. 20 (HealthDay News) -- The use of intravenous dextrose following surgery may reduce postoperative nausea and vomiting, according to research presented at the annual meeting of the American Society of Anesthesiologists, held from Oct. 17 to 21 in New Orleans.