Blood Products Transfusion

Transfusion of blood products may be required during the perioperative period. Despite a well-established safety record, transfusion of blood and its components is not risk free. Indication for each of the blood components needs to be established based on the laboratory investigation and/or clinical picture. In general terms, when there is a clinical evidence of a deficiency in oxygen-carrying capacity, red cell transfusion should be considered; and in the situations of clinically significant coagulopathy, hemostatic blood products (frozen plasma, platelets, cryoprecipitate, factor concentrates) transfusion should be considered. Complications of blood administration range from rare but severe reactions (hemolytic transfusion reactions) to more common, and also associated with significant morbidity and mortality, such as transfusion-related acute lung injury (TRALI), transfusion-related circulatory overload (TACO), and changes in immune system (transfusion related immunomodulation [TRIM]).

Preprocedural Assessment for Sedation in Gastrointestinal Endoscopy

The role of the anesthesia service in sedation for gastrointestinal endoscopy (GIE) has been steadily increasing. The goals of preprocedural assessment are determined by the specific details of the procedure, the issues related to the illness that requires the endoscopy, comorbidities, the goals for sedation, and the risk of complications from the sedation and the endoscopic procedure. Rather than consider these issues as separate entities, they should be considered as part of a continuum of preparation for GIE. This is told from the perspective of an anesthesiologist who regularly participates in the full range of sedation for GIE.

Time to Loosen the Apron Strings: Cohort-based Evaluation of a Learner-driven Remediation Model at One Medical School

BACKGROUND

Remediation in the era of competency-based assessment demands a model that empowers students to improve performance.

AIM

To examine a remediation model where students, rather than faculty, develop remedial plans to improve performance.

SETTING/PARTICIPANTS

Private medical school, 177 medical students.

PROGRAM DESCRIPTION

A promotion committee uses student-generated portfolios and faculty referrals to identify struggling students, and has them develop formal remediation plans with personal reflections, improvement strategies, and performance evidence. Students submit reports to document progress until formally released from remediation by the promotion committee.

PROGRAM EVALUATION

Participants included 177 students from six classes (2009-2014). Twenty-six were placed in remediation, with more referrals occurring during Years 1 or 2 (n = 20, 76 %). Unprofessional behavior represented the most common reason for referral in Years 3-5. Remedial students did not differ from classmates (n = 151) on baseline characteristics (Age, Gender, US citizenship, MCAT) or willingness to recommend their medical school to future students (p < 0.05). Two remedial students did not graduate and three did not pass USLME licensure exams on first attempt. Most remedial students (92 %) generated appropriate plans to address performance deficits.

DISCUSSION

Students can successfully design remedial interventions. This learner-driven remediation model promotes greater autonomy and reinforces self-regulated learning.

Nonoperating room anesthesia for the gastrointestinal endoscopy suite

Anesthesia services are increasingly being requested for gastrointestinal (GI) endoscopy procedures. The preparation of the patients is different from the traditional operating room practice. The responsibility to optimize comorbid conditions is also unclear. The anesthetic techniques are unique to the procedures, as are the likely events that require intervention by the anesthesia team. The postprocedure care is also unique. The future needs for anesthesia services in GI endoscopy suite are likely to expand with further developments of the technology.

Electromagnetic interference in a cardiac pacemaker during cauterization with the coagulating, not cutting mode

Electromagnetic interference in pacemakers has almost always been reported in association with the cutting mode of monopolar electrocautery and rarely in association with the coagulation mode. We report a case of electrocautery-induced electromagnetic interference with a DDDR pacemaker (dual-chamber paced, dual-chamber sensed, dual response to sensing, and rate modulated) in the coagulating and not cutting mode during a spine procedure. We also discuss the factors affecting intraoperative electromagnetic interference. A 74-year-old man experienced intraoperative electromagnetic interference that resulted in asystole caused by surgical electrocautery in the coagulation mode while the electrodispersive pad was placed at different locations and distances from the operating site (This electromagnetic interference did not occur during the use of the cutting mode). However, because of careful management, the outcome was favorable. Clinicians should be aware that the coagulation mode of electrocautery can cause electromagnetic interference and hemodynamic instability. Heightened vigilance and preparedness can ensure a favorable outcome.

Assessment of competency in anesthesiology

Assessment of competency in traditional graduate medical education has been based on observation of clinical care and classroom teaching. In anesthesiology, this has been relatively easy because of the high volume of care provided by residents under the direct observation of faculty in the operating room. With the movement to create accountability for graduate medical education, there is pressure to move toward assessment of competency. The Outcome Project of the Accreditation Council for Graduate Medical Education has mandated that residency programs teach six core competencies, create reliable tools to assess learning of the competencies, and use the data for program improvement. General approaches to assessment and how these approaches fit into the context of anesthesiology are highly relevant for academic physicians.

Microdiscectomy: spinal anesthesia offers optimal results in general patient population

Spinal anesthesia provides a safe and highly satisfactory alternative to general anesthesia in patients undergoing limited lumbar surgery. Nevertheless, it is not commonly used for spinal surgery, and in some centers it is not even considered as an option for spinal procedures. This study presents the current anesthetic technique for patients undergoing microdiscectomy and compares the peri- and postoperative outcomes in 76 patients drawn from a case-controlled study group. Patients underwent microdiscectomy for herniated nucleus pulposus under spinal (43 patients) or general anesthesia (33 patients). Patients ranged from 18 to 40 years, and all were anesthesia class 1. Surgical and anesthesia times were longer for the general anesthetic group, as was total anesthetic time. Urinary retention was more common in the general anesthesia group (p = .035). Postanesthetic care unit admission times were significantly shorter among general anesthetic patients compared with spinal anesthetic patients (p < .001). Spinal anesthesia patients required less pain medication and experienced less nausea and emesis. Even among young, medically fit patients, spinal anesthesia provided specific advantages over general anesthesia, including decreased anesthesia time, decreased nausea and antiemetic requirements, reduced analgesic requirements, and a trend toward lower complication rates and shorter hospital stay. Both surgeon and patient satisfaction with this anesthetic approach is high.

Change in Cardiopulmonary Arrest Response in an Anesthesiology Residency: A practice-based learning initiative

Because of increases in the acuity in our patient population, increasing complexity of the care provided and the structure of our residency, we decided to systematically alter our participation in the hospital-wide cardiac arrest system. The need to provide optimum service in an increasingly complex clinical care system was the motivation for change. With substantive input from trainees and practitioners, we created a multi-tier-system of response along with predefined criteria for the anesthesiology response. We report the result of our practice based learning initiative.

Anesthetic management of a patient with stiff person syndrome

We describe the successful anesthetic management of a patient with stiff-person syndrome (SPS) undergoing a right inguinal hernia repair, using a somatic paravertebral block supplemented with conscious sedation. We also present the implications of general anesthesia in patients with SPS. The use of regional anesthetic techniques in patients with SPS has the advantage of avoiding exposure to muscle relaxants. The use of general anesthesia in patients with SPS carries the risk of postoperative hypotonia due to enhancement of gamma-aminobutyric acid action on synaptic transmission by drugs that have a gamma-aminobutyric acid agonistic action.

Inadvertent dural puncture during attempted thoracic epidural catheter placement complicated by cerebral and spinal subdural hematoma

Minor complications of inadvertent dural puncture during attempted epidural anesthesia are common, related to the size of the needle and the incidence of postdural puncture headache. Serious complications are much less common. We report a case where inadvertent dural puncture with an 18-gauge epidural needle was associated with the creation of intracranial and spinal subdural hematoma.

Teaching and evaluating professionalism for anesthesiology residents

The Accreditation Council for Graduate Medical Education Outcome Project requires teaching and evaluation of 6 core competencies, one of which is professionalism. Because of this initiative, anesthesiology residency programs are obliged to teach and evaluate professionalism for anesthesiology residents. We decided to create a system that would allow the teaching and evaluation of professionalism in the specific context of anesthesiology.

Hetastarch allergy and positive latex radioallergosorbent test in a patient suffering cardiovascular decompensation during multiple perioperative periods

The cause of sudden cardiovascular collapse in the perioperative period can be elusive. Allergy may be overlooked as a cause. When allergy is considered, latex is often suspected. Because hetastarch is frequently used in situations involving hypovolemia and hypotension, and because allergic reactions to it are rare, it may be overlooked as a possible allergen. We report a case of a patient suffering cardiovascular decompensation during four nonconsecutive perioperative periods before it was determined that she was allergic to hetastarch. She also had a very highly positive latex radioallergosorbent test, suggesting a latex allergy.

Epidural analgesia improves early rehabilitation after total knee replacement

STUDY OBJECTIVE

To compare epidural anesthesia and analgesia with spinal anesthesia with intravenous morphine analgesia for its effect on range of motion (ROM) and early rehabilitation after total knee replacement.

DESIGN

Randomized prospective study.

SETTING

Tertiary care, academic medical center.

PATIENTS

Thirty-eight patients scheduled for total knee replacement.

INTERVENTIONS

Patients were randomized into 2 groups. One group received spinal anesthesia with 0.5% bupivacaine and analgesia with intravenous patient-controlled analgesia morphine, demand mode only. The other group was given epidural anesthesia with 1.0% ropivacaine with 1:200,000 epinephrine and analgesia with 0.2% ropivacaine at 8 mL/h, maintained for 7 days. Both groups had compression stocking for deep venous thrombosis (DVT) prophylaxis, urinary catheter for the first 24 hours, and duplex scanning at days 3 and 10. The spinal group received low molecular-weight heparin for DVT prophylaxis.

MEASUREMENTS

Data collected included pain scores at rest, and with ROM, frequency of DVT, and patient satisfaction. Data were evaluated with Wilcoxon rank sum test for continuous variables and Fisher exact test for categorical variables. Data were considered significant at P < .05.

MAIN RESULTS

All 38 patients finished the study, 22 in the spinal group and 16 in the epidural group. There was no difference in demographics between groups. The pain sores at rest and with ROM were significantly less in the epidural group. ROM was better in the epidural group compared with the spinal group after day 1. No DVT was detected on day 3 or 10 in either group. No patient in either group required reinsertion of bladder catheter for urinary retention.

CONCLUSION

By using epidural analgesia in the first 7 days postoperatively, we achieved improved early rehabilitation due to excellent pain relief effect and an antithrombotic effect with an efficacy comparable to low molecular-weight heparin.

Changing of an anesthesiology clinical base year to create an integrated 48-month curriculum: experience of one program

To allow for growth in our anesthesiology residency, we assumed control of the clinical base year (postgraduate year 1[PGY-1]) and adjusted the curriculum to accommodate the expanded size. With this opportunity to change the curriculum, we created a clinical base year to prepare PGY-1 for clinical anesthesia training in PGY-2 to PGY-4 using, for this purpose, the best resources of our clinical site. We describe the process and preliminary results of the change.

Comparison of spinal and general anesthesia in lumbar laminectomy surgery: a case-controlled analysis of 400 patients

OBJECT

Despite a history of safety and efficacy, spinal anesthesia is rarely used in lumbar surgery. Application of regional anesthetics is widely preferred for lower-extremity surgery, but general anesthesia is used almost exclusively in spine surgery, despite evidence that spinal anesthesia is as safe and may offer some advantages.

METHODS

In this case-controlled study the authors analyzed outcomes obtained in 400 patients in whom either spinal anesthesia or general anesthesia was induced to perform a lumbar decompression. Patients were matched for anesthesia-related class, preoperative diagnosis, surgical procedure, and perioperative protocols. All aspects of surgery, recovery, postanesthesia care, and pain management were uniform irrespective of the anesthetic type. Case complexity was equivalent. An independent observer performed analysis of the data. Data from the intraoperative period through hospital discharge were collected and compared. Two hundred consecutive patients meeting inclusion criteria were included in each group. Patients were treated for either lumbar stenosis or herniated nucleus pulposus. Demographically, both groups were well matched. Anesthetic and operative times were longer for patients receiving a general anesthetic (p < 0.05), in whom more nausea and greater requirements for antiemetics and pain medication were also present during recovery (p < 0.05). Overall complication rates and, specifically, the incidences of urinary retention were significantly lower in spinal anesthesia--induced patients (p < 0.05). There were no neural injuries in either group, and the incidence of spinal headache was lower in patients receiving a spinal anesthetic (1.5% compared with 3%).

CONCLUSIONS

Spinal anesthesia was as safe and effective as general anethesia for patients undergoing lumbar laminectomy. Potential advantages of spinal anesthsia include a shorter anesthesia duration, decreased nausea, antiemetic and analgesic requirements, and fewer complications. Successful surgery can be performed using either anesthesia type.

The effect of epidural vs intravenous analgesia for posterior spinal fusion surgery

BACKGROUND

The study objective was to compare epidural vs intravenous postoperative analgesia in posterior spinal fusion surgery patients.

METHODS

This prospective, double-blinded, randomized study was performed in a tertiary care teaching hospital involving 31 American Society of Anesthesiologists physical status I and II adolescent/young adult patients scheduled for elective posterior spinal fusion surgery for idiopathic scoliosis. Patients were divided into three treatment groups according to the epidural solution infused: group 1 (n = 10) 0.1% bupivacaine + 5 microg x ml(-1) fentanyl; group 2 (n = 12) 0.0625% bupivacaine + 5 microg x ml(-1) fentanyl; group 3 (n = 9) 0.9% sodium chloride (placebo). During general anesthesia all patients received a directly placed midthoracic epidural catheter with a set infusion rate followed by morphine sulfate intravenous patient-controlled analgesic device postoperatively. Morphine sulfate usage and visual analog scores were evaluated at 4 h intervals postoperatively for up to 96 h. Postoperative time to liquids, solid food, ambulation, length of stay, discontinuation of Foley catheter, and side effects were recorded.

RESULTS

No consistent difference was detected on intravenous morphine dose usage, visual analog scores, or estimated pain scale over the whole follow-up period. No difference was observed in the epidural groups in time to oral intake of liquids or solids, ambulation, bowel sounds, or length of stay when compared with placebo.

CONCLUSIONS

By evaluating morphine sulfate usage between groups, the analgesic effectiveness of continuous thoracic epidural analgesia bupivacaine and fentanyl doses used revealed no significant improvement over intravenous morphine sulfate analgesia alone in patients after posterior spinal fusion surgery.

Complications associated with lumbar laminectomy: a comparison of spinal versus general anesthesia

STUDY DESIGN

A case-controlled, comparative study of 400 patients undergoing lumbar surgery, treated with either spinal or general anesthesia. An independent observer analyzed outcomes.

OBJECTIVES

To determine the rate and type, of perioperative complications associated with each anesthetic method among lumbar surgery patients.

SUMMARY OF BACKGROUND DATA

Spinal anesthesia is infrequently used for spinal procedures. While complications associated with spinal anesthesia are rare, some authors have suggested that spinal anesthesia may exacerbate existing neurologic disease and have recommended against its use in lumbar disc surgery. Others have found the technique safe and effective. General anesthesia may be preferred because it is seen as the routine accepted practice, because of greater patient acceptance and the ability to perform longer operations, or because of a general sense that general anesthesia is "safer" in these procedures.

METHODS

Patients treated between 1994 and 1998 were matched for anesthetic class, preoperative diagnosis, surgical procedure, and perioperative protocols. All patients were treated according to a uniform protocol and recovered in the same perianesthetic environment. Data from the intraoperative period through hospital discharge were collected and compared.

RESULTS

A total of 200 patients were included in each group. Overall complication rates and time to discharge were significantly lower in spinal anesthetic patients. Total anesthetic and operative times were significantly longer for general anesthetic patients, and perioperative heart rate and mean arterial pressures were elevated compared with those in spinal anesthetic patients. Nausea, requirements for antiemetic medication, and the incidence of urinary retention were significantly increased among general anesthesia patients. Spinal anesthesia patients had fewer spinal headaches compared with the general anesthetic group, but statistical significance was not obtained.

CONCLUSIONS

For patients undergoing decompressive lumbar surgery, spinal anesthesia is at least comparable to general anesthetic with respect to complications. Specific advantages to spinal anesthesia include decreased nausea and antiemetic requirements, reduced analgesic requirements, and reduced overall complication rate.

Pressure Sore as a Complication of Labor Epidural Analgesia

Lumbar epidural analgesia has become a common mode of pain control for laboring patients. Side effects, such as hypotension, motor blockade, respiratory depression, dural puncture, and urinary retention, are well described. Although pressure sores have been thought of as a complication limited to elderly, emaciated, unconscious, or bedridden patients, we describe the occurrence of pressure sores in a young and healthy parturient after lumbar epidural analgesia.

IMPLICATIONS

We report a pressure sore that resulted from lumbar epidural analgesia for labor.

Anesthetic considerations of the herbal, kava

The herbal remedy, kava, is reviewed, with special focus on the anesthetic management of the perioperative patient. Consumption of kava has potential cardiovascular consequences that could manifest in the perioperative period. Kava may act through inhibition of sodium and calcium channels to cause direct decreases in systemic vascular resistance and blood pressure. Kava inhibits cyclooxygenase to potentially cause a decrease in renal blood flow and to interfere with platelet aggregation. Kava may also cause adverse neurologic effects because of benzodiazepine and antidepressant activities on noradrenergic and/or serotoninergic pathways that may potentiate benzodiazepine and induction anesthetic potency and cause excessive perioperative sedation. Patients often do not disclose their use of herbal substances, and drug interaction can occur without being suspected as the cause for a change in patient homeostasis. A role for patient education about the potential adverse consequences of kava use in the perioperative period is suggested.

Subarachnoid catheter placement after wet tap for analgesia in labor: influence on the risk of headache in obstetric patients

BACKGROUND AND OBJECTIVES

The incidence of postdural puncture headache (PDPH) after epidural wet tap for obstetric patients may be as high as 75%. We have studied how subsequent placement of a subarachnoid catheter immediately after confirmation of a wet tap, and leaving the catheter in place for 24 hours affects the incidence of PDPH.

METHODS

Over a 5-year interval, 115 consecutive patients who had unintentional dural puncture were divided into 3 groups by consecutive assignment. Group A had an epidural catheter placed at another interspace. Group B had a subarachnoid catheter placed for labor analgesia that was removed immediately after delivery. Group C had a subarachnoid catheter that was left in place for 24 hours after delivery. Data were collected retrospectively. The incidence of PDPH and blood patch was compared between groups.

RESULTS

The overall incidence of PDPH was 46.9% and need for blood patch 36.5%, significantly less in both subarachnoid catheter groups, 31% in B and 3% in group C, compared with group A (PDPH 81%) (P <.001).

CONCLUSION

Subarachnoid catheter placement after wet tap in obstetric patients reduces the PDPH rate and does so to a greater extent if left in place for 24 hours after delivery.

Leukocyte reduction during orthotopic liver transplantation and postoperative outcome: a pilot study

STUDY OBJECTIVE

To investigate the effect of intraoperative leukocyte reduction of administered blood products on the incidence of acute cellular rejection and postoperative patient outcome.

DESIGN

Prospective, nonrandomized, historical control study.

SETTING

Academic tertiary medical center.

PATIENTS

The study group (Group 1) consisted of 30 consecutive adult patients with end-stage liver disease scheduled to undergo orthotopic liver transplantation (OLT) between 1998 and 2000. The historical control group (Group 2) consisted of 30 adult patients with end-stage liver disease matched to study group patients as closely as possible for age, gender, and etiology of liver disease who underwent OLT between 1995 and 1999.

INTERVENTIONS

Group 1 patients had all intraoperative allogeneic and cell salvaged blood products leukocyte reduced before administration. Group 2 patients underwent OLT without leukocyte filtration of any administered blood products.

MEASUREMENTS

Demographic data were collected for both patient groups and included age, gender, etiology of liver disease, and both intraoperative and postoperative immunosuppression. Demographic allograft donor data for both patient groups were collected and included age, gender, use of vasopressors during procurement, and cold and warm donor organ ischemic times. Outcome variables measured included incidence of acute cellular rejection, length of intensive care unit (ICU) and length of hospital stay, incidence of both graft loss and retransplantation, and mortality.

MAIN RESULTS

The incidence of acute cellular rejection was 40% in Group 1 and 66.7% in Group 2 (p = 0.037). Length of ICU stay was 3.0 (2.0, 5.0) days in Group 1 and 4.0 (3.0, 6.0) days in Group 2 (p = 0.16). Length of hospital stay was 14.0 (11.0, 18.0) days in Group 1 and 18.0 (14.0, 27.0) days in Group 2 (p = 0.035). One allograft was lost in Group 2 because of primary nonfunction requiring retransplantation (p = 0.31), and three postoperative deaths occurred in Group 1 as a result of multisystem organ failure (p = 0.08).

CONCLUSIONS

Coincident with leukocyte reduction of all administered blood products during OLT, an improved outcome was observed in Group 1 patients as demonstrated by both a decreased incidence of acute cellular rejection and length of hospital stay.

Diaspirin-crosslinked hemoglobin reduces blood transfusion in noncardiac surgery: a multicenter, randomized, controlled, double-blinded trial

In this randomized, prospective, double-blinded clinical trial, we sought to investigate whether diaspirin-crosslinked hemoglobin (DCLHb) can reduce the perioperative use of allogeneic blood transfusion. One-hundred-eighty-one elective surgical patients were enrolled at 19 clinical sites from 1996 to 1998. Selection criteria included anticipated transfusion of 2-4 blood units, aortic repair, and major joint or abdomino-pelvic surgery. Once a decision to transfuse had been made, patients received initially up to 3 250-mL infusions of 10% DCLHb (n = 92) or 3 U of packed red blood cells (PRBCs) (n = 89). DCLHb was infused during a 36-h perioperative window. On the day of surgery, 58 of 92 (64%; confidence interval [CI], 54%-74%) DCLHb-treated patients received no allogeneic PRBC transfusions. On Day 1, this number was 44 of 92 (48%; CI, 37%-58%) and decreased further until Day 7, when it was 21 of 92 (23%; CI, 15%-33%). During the 7-day period, 2 (1-4) units of PRBC per patient were used in the DCLHb group compared with 3 (2-4) units in the control patients (P = 0.002; medians and 25th and 75th percentiles). Mortality (4% and 3%, respectively) and incidence of suffering at least one serious adverse event (21% and 15%, respectively) were similar in DCLHb and PRBC groups. The incidence of jaundice, urinary side effects, and pancreatitis were more frequent in DCLHb patients. The study was terminated early because of safety concerns. Whereas the side-effect profile of modified hemoglobin solutions needs to be improved, our data show that hemoglobin solutions can be effective at reducing exposure to allogeneic blood for elective surgery.

IMPLICATIONS

In a randomized, double-blinded red blood cell controlled, multicenter trial, diaspirin-crosslinked hemoglobin spared allogeneic transfusion in 23% of patients undergoing elective noncardiac surgery. The observed side-effect profile indicates a need for improvement in hemoglobin development.

Horner's syndrome and trigeminal nerve palsy after lumbar epidural analgesia for labor and delivery

This report highlights transient Horner's syndrome and trigeminal nerve palsy following labor epidural analgesia. A 29-year-old primigravida had a lumbar epidural catheter placed for analgesia in labor. The analgesia was maintained by infusion of a dilute local anesthetic/opioid mixture and turned off after achieving complete cervical dilation. Approximately 1 hour after delivery she complained of heaviness in her left eyelid, and was noted to have left-sided ptosis and paresthesia within the distribution of the ophthalmic and maxillary divisions of the trigeminal nerve, which resolved over the next 2 hours. There were no other neurologic changes. Horner's syndrome and cranial nerve palsies can occur as a consequence of epidural analgesia for labor.

Effect of diaspirin crosslinked hemoglobin (DCLHb HemAssist) during high blood loss surgery on selected indices of organ function

BACKGROUND

The safety of the hemoglobin based oxygen carrier diaspirin crosslinked hemoglobin (DCLHb) has been reported only in the low (50-200 mg/kg) dose range [Przybelski. R.J.; Daily, E.K.; Kisicki, J.C.; Mattia-Goldberg, C.; Bounds, M.J.; Colburn, W.A. Phase I study of the safety and pharmacologic effects of diaspirin crosslinked hemoglobin solution. Crit. Care Med. 1996, 24 (12), 1993-2000, Bloomfield, E.; Rady, M.; Popovich, M.; Esfandiari, S.; Bedocs, N. The use of diaspirin crosslinked hemoglobin (DCLHb 1996, 95, (3A), A220.]. We conducted a randomized prospective open-label trial of DCLHb and packed red blood cells (PRBCs) in high-blood loss surgical patients to show the effect of 750 ml DCLHb (approximately 1000 mg/kg) on selected indices of organ function.

METHOD

After institutional approval, 24 patients scheduled to undergo elective orthopedic or abdominal surgery, were randomized to receive either PRBCs or 10% DCLHb within 12 hours after the start of surgery. Patients with renal insufficiency, abnormal liver function, severe coronary artery disease (CAD) and ASA physical status > or = IV were excluded. The anesthetic technique was left to the judgment of the anesthesiologist. Autologous predonation and intraoperative blood conservation techniques were utilized as appropriate. The indications for blood transfusion were individualized on disease state, stage of surgery, and plasma Hb concentration. Laboratory studies were obtained preoperatively and up to 28 days postoperatively. Patients were observed daily for development of jaundice, hematuria, nausea, vomiting, gastrointestinal discomfort, cardiac, respiratory, and infectious complications. Organ effects were assessed with urinalysis, creatinine clearance, electrocardiogram (ECG), and a panel of blood and serum laboratory tests.

RESULTS

The dose of DCLHb administered ranged from 680-1500 mg/kg (mean = 999 mg/kg). Estimated blood loss was 27 +/- 13 ml/kg and 31 +/- 15 ml/kg in the control and DCLHb groups, respectively. Fewer PRBCs (1.9 +/- 1.2 vs. 3.4 +/- 2.4 units. P = 0.06) were transfused to DCLHb patients on the operative day although this difference was no longer apparent later on. In the DCLHb group, 4/12 patients avoided any allogeneic PRBC transfusion vs. none in the control group (P = 0.09). Systolic, diastolic and mean blood pressure increased moderately after DCLHb for a period of 24-30 hours. There were no occurrences of cardiac ischemia. myocardial infarction, stroke, or pulmonary edema, by clinical or laboratory parameters up to the 28th postoperative day (POD). Seven of 12 (58%) DCLHb patients had yellow skin discoloration vs. none in the PRBC group (P < 0.01). Two of four non-urologic surgery patients developed asymptomatic postoperative hemoglobinuria after DCLHb. Creatinine clearance was unchanged postoperatively. Because of hemoglobin interference, bilirubin, gamma-glutamyl transferase (GGT), and amylase could not be measured reliably on POD1; on POD2. amylase was transiently elevated to 3 times ULN along with mild elevations of bilirubin, transaminases and BUN. Mean total creatine phoshokinase (CPK) peaked at 8 times the upper limit of normal (ULN) in the DCLHb group, compared with less than twice ULN for controls. Three DCLHb patients had prolonged ileus. Two of these patients had postoperative hyperamylasemia, one of whom developed mild pancreatitis. DCLHb did not affect white blood cell count or coagulation tests.

CONCLUSION

Administration of approximately 1000 mg/kg DCLHb was associated with transient arterial hypertension, gastrointestinal side effects, laboratory abnormalities, yellow skin discoloration, and hemoglobinuria. These observations point to opportunities for improvement in future synthetic hemoglobin design.

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.

Anesthetic implications of thoracic endometriosis

Endometriosis occurs in 5% to 10% of women of childbearing age and involves the proliferation of endometrial tissue outside the uterine cavity. Thoracic endometriosis is the most frequent extrapelvic manifestation of endometriosis, numbering some 100 reported cases. It may include spontaneous pneumothorax, hemoptysis, chest pain, bronchiectasis, pneumomediastinum, or mediastinal bleeding. Because the tissue is hormonally responsive, all of these manifestations are related to the menstrual cycle (catamenial) and are likeliest to occur during menses. We report the successful anesthetic management of a patient with thoracic endometriosis and recurring catamenial pneumothorax who presented for elective pelvic surgery.

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.

Interscalene brachial plexus anesthesia for shoulder surgery: report of a complicated intraoperative course

We present a case of abrupt hemodynamic and mental status changes that occurred during shoulder surgery. During interscalene anesthesia for rotator cuff repair, there was abrupt onset of altered mental status and hemodynamic changes, which had a variety of possible contributing causes. Complete recovery occurred during care in the post-anesthesia care unit. A variety of physiologic changes can occurred during interscalene anaesthesia for shoulder surgery, which require prompt identification and management.

Hemoglobin and methemoglobin concentrations after large-dose infusions of diaspirin cross-linked hemoglobin

Diaspirin cross-linked hemoglobin (DCLHb) solution is a purified human hemoglobin product chemically stabilized to deliver oxygen to tissues. We determined the peak plasma hemoglobin concentration and assessed changes in methemoglobin concentration after the infusion of 1 g/kg DCLHb in large blood loss surgical patients. This prospective, randomized study included 26 surgical patients who were either infused with up to three 250-mL units of 10% DCLHb or transfused with up to three units of packed red blood cells during the study infusion period. Serial plasma hemoglobin, plasma methemoglobin, and whole blood methemoglobin levels were measured before and at intervals up to 48 h after the study infusion period. Plasma hemoglobin and blood methemoglobin concentrations increased during the infusion of DCLHb. The plasma hemoglobin values in the DCLHb group continued to increase during each of the infusion periods to reach a peak plasma concentration of 1450 +/- 176 mg/dL. The fraction of whole blood methemoglobin increased from 0.84 +/- 0.77% at baseline to 4.08 +/- 1.36%. With a median DCLHb dose of 936 mg/kg (range 658-1500 mg/kg), the harmonic mean half-life was 10 h, and the increased whole blood methemoglobin reached a range not associated with complications.

IMPLICATIONS

The dose of diaspirin cross-linked hemoglobin (DCLHb) (936 +/- 276 mg/kg) used in this study was one of the largest reported in humans to date. The DCLHb mean half-life was 10 h. The half-life observed was 2-4 times that found at smaller doses in previous studies. Whole blood methemoglobin fraction increased during DCLHb infusion but did not reach a range associated with complications.

Intraarticular morphine and bupivacaine reduces postoperative pain after rotator cuff repair

BACKGROUND AND OBJECTIVES

To determine whether intraarticular injection of morphine, fentanyl, or sufentanil added to bupivacaine provided pain control after open rotator cuff repair.

METHODS

These data were collected as a prospective, randomized, blinded observer study. All patients received a standard interscalene anesthetic with 1.4% mepivacaine with 1:200,000 epinephrine. At the conclusion of surgery, they received an intraarticular injection after the shoulder capsule was closed. Patients were randomized into 4 groups. All received 20 mL of 0.25% bupivacaine: group 1, plain; group 2, with 1 mg of morphine added; group 3, with 50 microg of fentanyl added; and group 4, with 10 microg of sufentanil added. Pain scores in the postanesthesia care unit were evaluated at 0, 30, 60, 90, 120, and 240 minutes and at 4-hour intervals postoperatively using a visual analogue scale. Breakthrough pain was managed with morphine, via patient controlled analgesia pump.

RESULTS

Thirty-nine patients were entered into the study. Pain scores at 2 hours and beyond were lowest in group 2. Total morphine utilization was significantly lower for the first 24 hours in group 2.

CONCLUSIONS

Intraarticular injection of the shoulder with 0.25% bupivacaine and 1 mg morphine at the conclusion of surgery provided pain control and diminished morphine used in the first 24 hours after open rotator cuff repair. Fentanyl and sufentanil did not improve the analgesia over that achieved with bupivacaine alone.

Redefining the preoperative evaluation process and the role of the anesthesiologist

STUDY OBJECTIVE

To assess the effects of implementing an ambulatory and same-day surgery preoperative evaluation patient triage system over a 3-year period.

DESIGN

Retrospective analysis of 63,941 ambulatory surgical patients presenting for elective surgery.

SETTING

Tertiary care, academic medical institution.

INTERVENTIONS

The following preoperative evaluation model components were implemented over a 3-year period: HealthQuest, which is an outpatient preoperative assessment computer program developed by the Department of General Anesthesiology; a general internal medicine clinic designated specifically for preoperative evaluation and medical optimization; disease specific algorithms for both preoperative patient assessment and management; and a preoperative anesthesia clinic that no longer performs preoperative medical optimization.

MEASUREMENTS AND MAIN RESULTS

During the 3-year study period ambulatory and same-day surgical case volume increased 34.7%. A total of 50,967 patients used HealthQuest as part of their preoperative evaluation. Of these patients 22,744 (35.6%) did not need to see an anesthesiologist until the day of surgery as guided by both a computer-assigned HealthQuest score and surgical classification scheme. Also, 41,197 patients were evaluated in our anesthesia preoperative clinic with a cost per evaluation of $24.86, which increased only 0.9% per year. In addition, both patient interview time and patient dissatisfaction with the preoperative process decreased over the 3-year period. There were 20, 088 patient encounters in the general internal medicine clinic for patient medical evaluation and optimization. The average monthly preoperative surgical delay rate decreased 49% during the study period. Finally, significant monetary saving resulted due to decreased unnecessary laboratory testing.

CONCLUSIONS

Efficient, cost-effective patient care can be provided by using this preoperative evaluation model. Some institutions may find portions of this preoperative model applicable to their current situation.

The pharmacology of local anesthetics

The pharmacology of local anesthetics is an integration of the basic physiology of excitable cells and the mechanism by which local anesthetics are capable of interrupting conduction of neural messages. The common characteristics of the molecules with local anesthetic action have been identified and can explain the properties of the agents. These same chemical characteristics also explain toxicity of these agents and differences that exist between local anesthetics with similar structure.

Use of key words as an adjunctive learning tool improves learning during a perioperative medicine rotation for anesthesiology residents

Designing a successful block rotation for anesthesiology residents requires not only an appropriate curriculum but also a set of teaching tools, which promote learning. Traditional clinical rotations in Anesthesiology residencies emphasize clinical teaching, supported by interaction with staff. Since Perioperative Medicine is a nontraditional subject for anesthesia residents, we introduced a syllabus and didactic curriculum to support clinical teaching. We hypothesized that the use of key words would enhance learning. Alternating groups of residents were assigned to receive key words, while control residents were expected to learn without key words. The key words were delivered in writing on the first day of the rotation and the syllabus was highlighted to identify the key words in the text. Pretests and posttests were administered to residents participating in the perioperative rotation. Learning was assessed by calculating the change in test scores. There was significantly more learning in the group given the key words. We conclude that key word designation improved learning in a rotation designed to teach perioperative medicine.

Use of Key Words as an Adjunctive Learning Tool Improves Learning During a Perioperative Medicine Rotation for Anesthesiology Residents

Designing a successful block rotation for anesthesiology residents requires not only an appropriate curriculum but also a set of teaching tools, which promote learning. Traditional clinical rotations in Anesthesiology residencies emphasize clinical teaching, supported by interaction with staff. Since Perioperative Medicine is a non-traditional subject for anesthesia residents, we introduced a syllabus, and didactic curriculum to support clinical teaching. We hypothesized that the use of key words would enhance learning. Alternating groups of residents were assigned to receive key words, while control residents were expected to learn without key words. The key words were delivered in writing on the first day of the rotation and the syllabus was highlighted to identify the key words in the text. Pre and post-tests were administered to residents participating in the perioperative rotation. Learning was assessed by calculating the change in test scores. There was significantly more learning in the group given the key words. We conclude that key word designation improved learning in a rotation designed to teach perioperative medicine.

Autonomic dysfunction in end-stage liver disease manifested as defecation syncope: impact of orthotopic liver transplantation

Patients with end-stage liver disease (ESLD) may be at increased risk for syncopal episodes based on their circulatory physiological state. Although a definitive cause for this is not known, several mechanisms have been proposed. In patients with ESLD, defecation syncope may result from a failure of short-term neurocirculatory adaptation to the Valsalva maneuver in the face of a hyperdynamic circulatory state and a decreased effective intravascular volume. We describe 2 patients with ESLD who had repeated episodes of defecation syncope before orthotopic liver transplantation (OLT). The most effective treatment of these syncopal episodes appears to be fluid administration and the use of a pressor agent, such as dopamine, to help maintain both an effective heart rate and intravascular volume. Correction of this altered circulatory physiological state through OLT prevented further syncopal episodes in both patients. A search of the literature failed to show previous reports associating ESLD and defecation syncope. Possible mechanisms favoring this association are reviewed.