AnesthesiaWeb - Archive - Lit Reviews 2000

Literature Reviews: 2000

February 2000
Safety of Pediatric Short-Stay Tonsillectomy.

Ambulatory management has become the established routine for most children undergoing tonsillectomy and adenotonsillectomy. There has, however, been continuing and justifiable concern about what constitutes an adequate interval of postoperative observation before discharge. The goal of this retrospective study of 134 children was to compare the safety of a relatively brief (less than 3 hr) postoperative observation period with the standard observation periods (6 to 8 hrs) described in the literature.

February 2000
The effective dose of dexamethasone for antiemesis after major gynecological surgery.

Postoperative nausea and vomiting is one of the most common and distressing side effects after surgery performed under general anesthesia. Moreover, it is one of the most frequent causes of delayed discharge and unanticipated hospital admission following (planned) ambulatory surgery

February 2000
Trends in quality of anesthesia care associated with changing staffing patterns, productivity, and concurrency of case supervision in a teaching hospital.

I'm flying on a plane as I pen this commentary. I'm thinking, OK, suppose there's only one pilot in there and he makes a mistake? Do we fall out of the sky? As experienced as he may be, he might still miss some crucial piece of information, imperfectly assimilate some data, or not recover from some freak environmental wind gust.

February 2000
Ulnar nerve pressure: influence of arm position and relationship to somatosensory evoked potentials.

Will we ever understand perioperative neuropathy? A fresh approach offers hope and insight (editorial).

February 2000
Which Clinical Anesthesia Outcomes Are Important to Avoid? The Perspective of Patients.

We seek to provide high quality anesthesia. However, the recipients of our care, the patients, must define this. Quality of anesthesia arises from the patients' subjective assessment of their desire for different health states, expressed as preferences for specific clinical anesthesia outcomes. Patient preferences for clinical outcomes are difficult to discern without informing patients about the expected outcomes of the procedure, and asking them about their specific preferences in a structured manner.

February 2000
Comparison of Vital Capacity Induction with Sevoflurane to Intravenous Induction with Propofol for Adult Ambulatory Anesthesia.

Propofol is probably the most commonly used intravenous induction agent for adult ambulatory anesthesia. However, inhalation induction with sevoflurane may be another option. In this study, the authors compared intravenous (IV) induction with propofol 2mg/kg with a vital capacity inhalation (VCI) technique with sevoflurane. For the VCI induction, the anesthesia circuit was primed with 8% sevoflurane and 75% N₂O in O₂ until the inspired limb drug concentration measured greater than 6%; this took approximately 45 seconds.

February 2000
Placenta previa: a 22-year analysis

Frederiksen's article in the American Journal of Obstetrics & Gynecology concluded that in women with placenta previa, general anesthesia increased intraoperative blood loss and the need for blood transfusion. This conclusion cannot be reasonably supported because the study design is retrospective and therefore cannot correct for the selection bias that may have occurred in these patients. As such, this article should not have appeared, as written, in this major obstetrical journal.

February 2000
Spinal versus epidural anesthesia for cesarean section in severely preeclamptic patients: a retrospective survey

In the past Gerti Marx and others have demonstrated the value of using epidural analgesia in preeclamptic patients. Hood's article introduces the changing anesthetic practice for managing patients with severe preeclampsia who require cesarean section.

February 2000
A Prospective, Randomized Comparison of Preoperative and Continuous Balanced Epidural or Paravertebral Bupivacaine on Post-Thoracotomy Pain, Pulmonary Function and Stress Responses.

Although epidural analgesia has been shown to be highly effective, the technical aspect of inserting these catheters in the mid-thoracic region remains difficult for many practitioners. Even in qualified hands, these catheters are not always successfully placed. This important study by Richardson, et al. compares the use of continuous balanced analgesia using epidural or paravertebral bupivacaine on post-thoracotomy pain, pulmonary function and stress responses.

February 2000
Randomized Trial of Hypotensive Epidural Anesthesia in Older Adults.

Deliberate hypotension has been promoted as a means of providing dry surgical fields or decreasing blood loss during certain procedures. A wide variety of techniques have been developed to achieve deliberate hypotension. These techniques have been used in healthy young patients and in surgical procedures that cannot be performed under normotensive conditions. It has been widely held that elderly patients or patients with pre-existing cardiovascular disease or renal dysfunction may be at significant risk for ischemic injury in nonsurgical regions, such as the kidney, brain or heart.

March 2000
Recovery of Cognitive Function After Remifentanil-Propofol Anesthesia: A Comparison with Desflurane and Sevoflurane Anesthesia

Available options for ambulatory general anesthesia now include several agents that may promote faster recovery. These include the inhaled anesthetics desflurane and sevoflurane and the opioid remifentanil. This German study enrolled 60 healthy ASA 1 and 2 patients scheduled for elective operative procedures. Patients were randomly assigned to receive either total intravenous anesthesia (TIVA) with remifentanil and propofol, balanced anesthesia with desflurane fentanil nitrous oxide or balanced anesthesia with sevoflurane fentanil nitrous oxide.

March 2000
The Benefits of Intraoperative Small-Dose Ketamine on Postoperative Pain After Anterior Cruciate Ligament Repair

The activation of N-methyl-D-aspartate (NMDA) receptors enhances central nervous system sensitization and therefore the intensity of perceived postoperative pain. NMDA receptors are activated by C-fiber inputs, which are in turn triggered by surgical tissue trauma via nociceptive transmitter release in the dorsal horn of the spinal cord. It has been proposed that analgesic drugs might more adequately prevent this central sensitization when administered before the tissue trauma--this is the concept of preemptive analgesia.

March 2000
Advantages of Fentanyl Over Morphine in Analgesia for Ventilated Newborn Infants After Birth: A Randomized Trial

Saarenmaa et al., compared fentanyl with morphine for analgesia given to ventilated newborns. The groups were evenly matched for age, weight, need for dopamine infusions, and a variety of other factors. The incidence of hypotension and urinary retention was similar but the incidence of gastrointestinal motility problems was significantly lower in the fentanyl group. The authors concluded that both drugs were effective in reducing the hormonal responses to stress and provided equivalent hemodynamic stability.

March 2000
Do Sick Newborn Infants Benefit From Participation in Randomized Clinical Trials?

Schmidt et al examined the outcomes of sick newborn infants who participated in controlled clinical trials. I have long been an advocate of giving children the same benefits of drug development as adults and several previous commentaries have addressed this topic.

March 2000
Morphine Pharmacokinetics and Pain Assessment in Premature Newborns

Scott et a.,l examined the pharmacokinetics versus postconceptual age of morphine in preterm infants. The plasma half-life of fentanyl was inversely related to postconceptual age with regards to developmental changes in cardiac output, hepatic function and renal function, as would be expected. The half-life was also longer than that previously reported. The authors attempted to correlate pain scores with blood levels of morphine. They were unable to demonstrate a relationship.

March 2000
Lytic Therapy for Stroke

March 2000
Two-Lung and One-Lung Ventilation in Patients with Chronic Obstructive Pulmonary Disease: The Effects of Position and F(IO)₂

This is a very interesting article, which addresses a finding that is not well known. The respiratory effects of one lung ventilation (OLV) have been well studied. However, most measurements have been made in the lateral position because surgery that has required OLV has traditionally been done in this position. The authors correctly point out that many approaches to cardiac and thoracic procedures now utilize OLV in the supine position.

March 2000
Approaches to the Prevention of Perioperative Myocardial Ischemia

This is a brief review of approaches to the prevention of myocardial ischemia which examines established methods and presents potential future therapeutic agents. The authors point out that the anesthesiologist can often implement pharmacologic and anesthetic interventions to improve perioperative outcomes in patients with CAD undergoing surgical procedures. Myocardial oxygen supply and demand are nicely reviewed, and anesthesiologists are advised to make an aggressive attempt to favorably alter this balance, much as one would monitor for ischemia in a patient with known or suspected CAD.

March 2000
A New Anterior Approach to the Sciatic Nerve Block

The combination of sciatic and femoral nerve blocks is a valid alternative to general anesthesia or neuroaxial block for patients undergoing surgery of the lower extremity. The peripheral nerve blocks also have the additional advantage of providing prolonged postoperative analgesia. Recent surveys have indicated that the sciatic nerve blocks are the procedure least frequently performed by anesthesiologists.

March 2000
Epidural Naloxone Reduces Pruritus and Nausea without Affecting Analgesia by Epidural Morphine in Bupivacaine

The authors of this study set out to determine whether or not epidural naloxone was capable of preserving analgesia while minimizing side effects caused by epidural morphine.

April 2000
The Effect of Bisoprolol on Perioperative Mortality and Myocardial Infarction in High-Risk Patients Undergoing Vascular Surgery.

This landmark study provides clear evidence that high-risk patients can have their risk of death and myocardial infarction (MI) decreased by a fairly simple therapy: beta blockade

April 2000
Intrathecal Ropivacaine for Ambulatory Surgery: A Comparison Between Intrathecal Bupivacaine and Intrathecal Ropivacaine for Knee Arthroscopy.

One can glean two important findings from this study. The first is that spinal ropivacaine 12 mg is approximately equivalent to bupivacaine 8 mg. At this dose, ropivacaine offers no significant advantage compared with bupivacaine for ambulatory surgery because the time until the patient can walk or void (important discharge criteria for outpatients) is more than 3 hours for both agents

April 2000
The Effects of Sevoflurane on Serum Creatinine and Blood Urea Nitrogen Concentrations: A Retrospective, Twenty-two Center, Comparative Evaluation of Renal Function in Adult Surgical Patients

With more than 45 million administrations worldwide, sevoflurane has become a popular anesthetic agent, especially in the ambulatory setting. The favorable anesthetic properties of sevoflurane, including its lack of pungency and low solubility, are well known, and although no case of an adverse renal outcome attributable solely to sevoflurane had been documented, nonetheless its potential nephrotoxicity is still hotly debated

April 2000
The Use of Caffeine for the Treatment of Post Dural Puncture Headache

In North America the per capita adult consumption of caffeine (1, 3, 7-trimethylxanthine) averages 100-200mg per day, the majority of which is ingested as coffee, which contains between 85-250 mg per cup (average, 175 mg). Caffeine is well absorbed from the gastrointestinal tract and reaches a peak blood level in about one hour after ingestion.

April 2000
Walking With Labor Epidural Analgesia: The Impact of Bupivacaine Concentration and a Lidocaine-Epinephrine Test Dose.

This careful, well planned study demonstrates that 15 mL of 0.125% bupivacaine with 10 µg sufentanil results in adequate analgesia within 20 minutes of epidural establishment, and will allow 90% of parturients to ambulate at some point during their labor. The information is useful for this specific recipe of local anesthetic and narcotic drug mass and the 15 mL volume of solution, and it may help a practitioner understand and choose a mixture to achieve analgesia and ambulation during labor

May 2000
Sedative, Amnestic, and Analgesic Properties of Small-Dose Dexmedetomidine Infusions

Alpha₂ adrenergic agonists provide sedation and analgesia with maintained cardiorespiratory function. Large doses of ₂ adrenergic agonists such as clonidine have been used, but the MAC-sparing effects are complicated by persistent hypotension requiring treatment as well as hypertension arising from ₂ -receptor mediated vascular constriction.

May 2000
The Visual Analog Scale Allows Effective Measurement of Preoperative Anxiety and Detection of Patients' Anesthetic Concerns

Anxiety before elective surgery is common. Therefore, many studies have examined interventions to reduce preoperative anxiety, including pharmacologic anxiolysis, information, distraction, and relaxation procedures. This study compared different methods to measure preoperative anxiety. The aims of the study were threefold. First, to examine the validity and utility of the self-reporting visual analog scale (VAS) and to compare this test to the standard Spielberger State-Trait Anxiety Inventory (STAI). Second, to find out whether the authors could identify patient risk factors or operations that correlated with high preoperative anxiety. Third, to itemize the concerns of patients admitted for elective anesthesia and surgery. The study was conducted in a university hospital in Switzerland.

May 2000
Efficacy of recombinant human erythropoietin in the critically ill patient: a randomized, double-blind, placebo-controlled trial.

Randomized trial of diaspirin cross-linked hemoglobin solution as an alternative to blood transfusion after cardiac surgery. The DCLHb Cardiac Surgery Trial Collaborative Group.

May 2000
Spinal Nerve Function in Five Volunteers Experiencing Transient Neurologic Symptoms after Lidocaine Subarachnoid Anesthesia

Transient neurologic symptoms (TNS) after 5% lidocaine spinal anesthesia were first reported in 1993. Since that time, a number of case reports and clinical studies have documented the presence of these symptoms and the clinical scenarios in which they are commonly seen. Despite our ability to describe the incidence of this group of symptoms, the etiology of this condition remains unknown.

May 2000
Long-term Spinal Analgesic Delivery: A Review of the Preclinical and Clinical Literature

The March-April 2000 edition of Regional Anesthesia and Pain Medicine has provided us with an exhaustive review of the use of spinal analgesics. This review, published by Mark Wallace and Tony Yaksh, extends over 30 pages and reviews information gathered from 326 references. With the ongoing increase in the utilization of intraspinal delivery systems, it is extremely valuable to have a review of the history that led to the use of these medications and their delivery within the spinal canal, as well as the outcomes and potential problems that are associated with their administration. The first part of the article is a historical section that outlines early spinal drug delivery.

July 2000
Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome.

July 2000
Clinical and economic effects of pulmonary artery catheterization in nonemergent coronary artery bypass graft surgery.

Clinical and Economic Effects of Pulmonary Artery Catheterization

July 2000
Economic Outcome of Off-Pump Coronary Artery Bypass Surgery: A Prospective Randomized Study.

This is a study from 1999 done in the United Kingdom, which I reviewed in preparation for a talk. It is an important study, which should be investigated in the United States in a similar manner

July 2000
Anticoagulation for Cardiac Surgery In Patients Receiving Preoperative Heparin: Use of the High-Dose Thrombin Time.

This is a very interesting article, which addresses an increasingly common clinical problem: apparent heparin resistance in the patient receiving preoperative heparin infusion when attempting full anticoagulation for cardiopulmonary bypass (CPB). Adequate anticoagulation is necessary for CPB, with prolongation of the activated clotting time (ACT) being the most common method used to demonstrate appropriate anticoagulation. However, when studies were initially done correlating various ACT levels with adequate heparinization, many patients were not in-hospital on heparin drips.

July 2000
Epidural hematoma following epidural analgesia in a patent receiving unfractionated heparin for thromboprophylaxis.

In their recent paper, Sandhu et al., note that risk factors for hematoma formation after epidural anesthesia include coagulopathies (congenital and acquired), ankylosing spondylitis, traumatic epidural insertion, old age, and epidural catheter manipulation while anticoagulated. The risk of epidural hematoma in the absence of heparin is estimated to be 1:150,000.

July 2000
Nitroglycerin application during cesarean delivery: Plasma levels, fetal/maternal ratio of nitroglycerin, and effects in newborns.

This paper quantifies the amount of drug to which the fetal circulation is exposed after a 250-500 mg bolus of nitroglycerin (GTN) is given intravenously to its mother, and corroborates the clinical impression that the human fetus tolerates this drug exposure well.

July 2000
Maximum Tolerated Dose of Nalmefene in Patients Receiving Epidural Fentanyl and Dilute Bupivacaine for Postoperative Analgesia.

Patients receiving epidural opiates, either alone or in combination with local anesthetics frequently experience side effects, including nausea and pruritus. Treatment regimens for these side effects have included antihistamines, such as diphenhydramine, agonist/ antagonist drugs, such as nalbuphine, and antinausea agents, such as Reglan, droperidol or Ondansetron. Despite the use of these medications, in some patients these side effects remain difficult to relieve and it is necessary to reverse some of the effects of the opiate.

July 2000
Opioid Substitution to Improve the Effectiveness of Chronic Noncancer Pain Control: A Chart Review

The authors of this study evaluated the efficacy and tolerability of opioids in long-term management of chronic noncancer pain. There is no question that the management of chronic noncancer pain in patients is a challenge. The use of opiates for the management of long-term chronic noncancer pain remains quite controversial. This is in part due to the issues of addiction and tolerance and in part due to the variable success rates in using these medications to treat chronic nonmalignant pain. There is evidence to suggest that opioids can improve the level of analgesia and quality of life in some patients.

August 2000
A Comparison of the Costs and Efficacy of Ondansetron Versus Dolasetron for Antiemetic Prophylaxis

Post operative nausea and vomiting are common problems after outpatient surgery, and antiemetics are often necessary. In the class of serotonin [5-HT3] antagonist antiemetics, both ondansetron and dolasetron are clinically available in the USA. The optimum dose and timing of the administration of these drugs for antiemetic prophylaxis have not been settled. In addition, the comparative cost effectiveness has not been determined.

August 2000
The Stability of Remifentanil Hydrochloride and Propofol Mixtures in Polypropylene Syringes and Polyvinylchloride Bags at 22º-24º

Remifentanil and propofol are sometimes used together for anesthesia. However, we must consider whether both drugs remain active when they are given together - are they physically compatible? The propofol package insert discusses only compatibility with certain IV fluids. The remifentanil package insert states that remifentanil and propofol are compatible, but gives no relative concentration data.

August 2000
Anesthesia-related cardiac arrest in children: Initial findings of the pediatric perioperative cardiac arrest (POCA) registry.

Morray and colleagues set out to define current contributions to cardiac arrests that occur in the perioperative period. As outlined in their introduction, a number of previous studies have described children as being at increased risk for cardiac arrest compared with adults. Factors deemed to be important were young age, ASA physical status, emergency surgery, and underlying medical conditions.

August 2000
Cleared for take-off: The Anesthesiologist and the Palm Pilot

Anesthesiologists are by nature and by trade technological individuals; from the operating room (OR) to the intensive care unit (ICU), our motto could easily be 'gadgets are us'! For me, and in my practice, the Palm Pilot has become an indispensable tool for personal information and clinical care. The Palm Pilot� is part of a diverse group of devices known as Personal Digital Assistants or PDA's. PDA's are any hand-held device, which keeps track of names, dates, appointments, and etcetera.

August 2000
Eliminating blood transfusions: new aspects and perspectives

This very well written review article about the consequences of allogeneic blood transfusion also includes a discussion of methods to reduce and/or eliminate the need for allogeneic blood transfusion. The article is written by experts in this field and offers practical insights and suggestions.

August 2000
Postoperative Prophylactic Administration of �-Adrenergic Blockers in Patients at Risk for Myocardial Ischemia

This is an interesting article which adds to the weight of evidence in favor of using beta-adrenergic blockade for the management of perioperative ischemia. It further supports the theory that postoperative (in contrast to preoperative and intraoperative) ischemic events result in cardiac morbidity. We can all apply this data to the perioperative care of our patients with probable coronary artery disease (CAD) in an effort to reduce postoperative cardiac morbidity and mortality.

Sept 2000
Genomics at the millennium

September 2000
Epidural Catheter Tip Cultures: Results of a 4-year Audit and Implications for Clinical Practice

Providing postoperative analgesia using epidural catheters has become increasingly popular now that the benefits of this procedure have been demonstrated in numerous settings. Perhaps the most significant concern of the provider is the potential for the development of an epidural space infection. The consequences of this complication can be severe and include paresis or outright paralysis if the diagnosis is delayed. In patients in whom epidural space infection is suspected, it is routine to pull the epidural catheter and to culture the tip of the epidural catheter to determine what organism may be responsible for the epidural space infection.

Sept 2000
Human Chromaffin Cell Graft into the CSF for Cancer Pain Management:
A Prospective Phase II Clinical Study

Although the majority of patients with complaints of pain resulting from cancer can be successfully treated using the WHO three-step analgesic-ladder approach, some patients develop intolerable side effects and resistance to adjuvant treatments. In selected patients, the delivery of medications within the spinal fluid allows for a dramatic reduction in required dose and is associated with improved response and decreased side effects

October 2000
The Comparative Dose-Response Effects of Melatonin and Midazolam for Premedication of Adult Patients: A Double-Blinded, Placebo Controlled Study

This is an interesting study because it addresses the anxiolytic, sedative and amnesic effects of two different drugs against placebo. It is especially interesting because one of the drugs tested is melatonin, a non-prescription medication commonly used for treating jet lag.

October 2000
The Effect of Timing of Dexamethasone Administration on Its Efficacy As a Prophylactic Antiemetic for Postoperative Nausea and Vomiting

Postoperative nausea and vomiting (PONV) are strong predictors of protracted postoperative stay and unanticipated hospital admission in the (planned) ambulatory setting. Moreover, PONV are extremely distressing symptoms for patients, affecting not only their postoperative functional level but also their satisfaction with their entire anesthetic/surgical experience.

November 2000
Age Is Not an Impediment to Effective Use of Patient-controlled Analgesia by Surgical Patients

PCA Is Effective for Older Patients — But Are There Limits?

November 2000
Financial Impact If Payers Use Medicare Rates

Bob Johnstone and Carrie Hosaflook have written a very interesting article. Their conclusions mirror those from another article recently published in the Journal of Clinical Anesthesia on the same issue, albeit with a different slant. Basically, the government undervalues the provision of anesthesia services compared to similar services provided by other doctors.

November 2000
Pharmacokinetics of dopamine in healthy male subjects

November 2000
Prevention and Screening of Colon Cancer — What is the Right Test?

November 2000
Adverse sedation events in pediatrics: Analysis of medications used for sedation.

In the April and October issues of Pediatrics are two articles of interest to anesthesiologists. I generally avoid bringing attention to my own work but these articles represent over four years of work by six individuals who reviewed sedation disasters in children sedated by non-anesthesiologists for a great variety of procedures. We used critical incident analysis in the ways that prior research involving aviation disasters and anesthesiology-related adverse outcomes have been used to improve safety in these areas.

December 2000
Fenoldopam: Applications in Anesthesiology, Perioperative Medicine, and Critical Care Medicine

December 2000
Postoperative Death and Malpractice Suits: Is Autopsy Useful?

This is an interesting article about the usefulness of a postmortem examination, especially as related to determining the cause of a death. In the context of a malpractice suit, this has obvious implications for the anesthesiologist