News In Brief
A new study published in the May issue of Anesthesia and Analgesia, has found the ancient Chinese practice of acupuncture is effective for treating pain.
Researchers from the University of Munich used quantitative sensory testing to identify changes in pain sensitivity with acupuncture in 24 healthy volunteers. After applying acupuncture to the leg, the researchers found that pain thresholds increased by up to 50 percent. Effects were noted in both the treated leg and the untreated, or contralateral, leg.
The results provide a scientific background for the ancient practice of acupuncture, according to researchers.
“Our results show that contralateral stimulation leads to a remarkable pain relief,” said lead author Dominik Irnich, M.D. “This suggests that acupuncturists should needle contralaterally if the affected side is too painful or not accessible. For example, if the skin is injured or there is a dressing in place.”
The study also supported the effects of three different forms of acupuncture – manual acupuncture, needling alone and with the addition of high-frequency and low-frequency electrical stimulation. All treatments were performed by an experienced acupuncturist, applied to acupuncture points commonly used in pain management.
When children and adults with acute and chronic pain become immersed in video game action, they receive some analgesic benefit, and pain researchers presenting at the American Pain Society’s annual scientific meeting reported that virtual reality is proving to be effective in reducing anxiety and acute pain caused by painful medical procedures and could be useful for treating chronic pain.
“Virtual reality produces a modulating effect that is endogenous, so the analgesic influence is not simply a result of distraction but may also impact how the brain responds to painful stimuli,” said Jeffrey I. Gold, Ph.D., associate professor of anesthesiology and pediatrics, Keck School of Medicine, University of Southern California and director of the Pediatric Pain Management Clinic at Children’s Hospital of Los Angeles. “The focus is drawn to the game not the pain or the medical procedure, while the virtual reality experience engages visual and other senses.”
Dr. Gold noted that the exact mechanistic/neurobiological basis responsible for the VR analgesic effect of video games is unknown, but a likely explanation is the immersive, attention-grabbing, multi-sensory and gaming nature of VR. These aspects of VR may produce an endogenous modulatory effect, which involves a network of higher cortical and subcortical regions known to be associated with attention, distraction and emotion. Studies measuring the benefit of virtual reality pain management, therefore, have employed experimental pain stimuli, such as thermal pain and cold pressure tests, to turn pain responses on and off as subjects participate in virtual reality experiences.
Source: American Pain Society
Nearly half of all children battling terminal cancer suffer unduly in their final months of life and more needs to be done to alleviate their pain, an Australian health expert has said.
Professor Michael Cousins said a Melbourne-based study had shown that 46% of these children were reported by their parents to have suffered significantly from pain.
The research, by the Royal Children’s Hospital and published earlier this year, drew similar findings to a study of sick children in the US city of Boston published a decade ago.
Professor Cousins said this showed that under-treated pain was an overlooked and long-standing problem within healthcare systems.
He said more should be done to address the issue - particularly in children who could have difficulty communicating what they were feeling. “Much more can be done to help children with cancer pain,” said Professor Cousins, Head of Department of Anaesthesia and Pain Management at Sydney’s Royal North Shore Hospital.
“A major clinical, educational and research initiative in paediatric pain management is long overdue.
“Without this, many children will continue to suffer unnecessarily with major impacts on their future lives and those of their families.”
Source: www.au.news.yahoo.com
The International Anesthesia Research Society (IARS) has named Medge Owen, Professor of Obstetric Anaesthesia at Wake Forest University and Founder of Kybele, Inc, as their 2009 Teaching Recognition Award Winner for Innovation in Education, honouring her efforts to improve childbirth conditions in third world countries.
Dr. Owen has travelled extensively to developing nations, creating geo-specific educational programs in obstetric anaesthesia and neonatal resuscitation.
Most recently, Dr. Owen partnered with Ridge Hospital in Accra, Ghana where she helped the urban hospital reduce its maternal mortality and preventable still birth rates by over 30%. Since partnering with Kybele, Ridge Hospital has introduced computers and sonogram techniques, as surgical areas closely approach western standards.
Many hospitals in Ghana and other third-world countries do not have enough basic supplies or sufficiently-educated staff to offer their patients a safe and pain-free childbirth experience. In Ghana alone, one in 50 maternal patients will not survive the birth of their child, in comparison to the U.S. rate, one in 5,000.
Expectant mothers face labour without access to spinal blocks or pain medication, and in many cases, air conditioning and running water. Labour wards are crowded with patients, sometimes six to eight mothers giving birth in the same room. “Women are afraid to go to the hospital,” said Dr. Owen. “They are afraid they will never come out.”
In 2001, Dr. Owen founded Kybele, a non-profit organisation with the mission to offer every mother and newborn the opportunity to experience birth in a safe, respectful and supportive environment. Kybele assesses the local supplies of each country and designs specific childbirth protocols, including the administration of regional anaesthetics.
“The goal is to teach the local doctors and midwives how to save lives during childbirth,” said Owen. “We want to empower people locally by teaching them the tools and techniques to sustain progressive programs.”
“It is an honour to celebrate Dr. Owen’s work in Ghana,” said Robert Sladen, Chair of the IARS Board of Trustees. “The IARS mission is to improve patient care worldwide not only by stimulating and advancing scientific research, but also educating and disseminating knowledge. Dr. Owen exemplifies this mission.”
An Ohio inmate is using an unusual legal maneuver by asking what effect his allergy to anaesthesia could have on the state’s plans to execute him.
Lawyers for Darryl Durr say they uncovered evidence of his allergy in his prison medical record and have asked for a review to see what impact the allergy could have, if any.
Kathleen McGarry says a violent reaction to the powerful anaesthetic Ohio uses for the death penalty could deny Durr the quick and painless execution guaranteed by the Constitution.
Following reported problems in the use of infusions pumps, the FDA has announced that it will constrict the regulations on the use of these pumps for injecting drugs and other fluids in patients.
Hospital authorities use the pumps to carry intravenous anaesthesia drugs and there has been rise in the use of the pump at U.S. homes as well, for those patients who require regular infusions.
Highlighting the complexity of the problems arousing with the use of external infusion pumps, FDA has cited few serious incidents. It explained that it has come across 56,000 reports carrying complaints on the improper use of these pumps, over the last five years. These reports also included 500 death cases associated with the use of the devices.
Between 2004 and 2009, 87 recalls of infusion-pumps have been reported, said the FDA. As per the guidelines issued by the FDA, an additional testing of all the pumps would be undertaken before giving them a green signal for entering into the market.
Sugammadex is effective for the reversal of deep neuromuscular blockade in patients under sevoflurane anesthesia, according to researchers. “Sevoflurane enhances the neuromuscular blocking effect of rocuronium,” said Philippe Duvaldestin (Hôpital Henri Mondor, Créteil, France) and colleagues.
“Therefore, theoretically, the efficacy of sugammadex in reversing rocuronium-induced neuromuscular blockade may be diminished under sevoflurane anaesthesia.”
Duvaldestin et al assigned 102 patients, scheduled for elective surgery under propofol-induced and sevoflurane-maintained anaesthesia, to receive a rocuronium 0.9 mg/kg or vecuronium 0.1 mg/kg bolus, followed by as-needed doses to maintain neuromuscular blockade at 1 to 2 posttetanic counts.
The patients received sugammadex at doses of 0.5, 1.0, 2.0, 4.0, or 8.0 mg/kg to reverse neuromuscular blockade. The average times to achieve a train-of-fours (TOF) ratio of 0.9 with these doses were 79.8, 28.0, 3.2, 1.7, and 1.1 minutes, respectively, in the rocuronium group, and 68.4, 25.1, 9.1, 3.3, and 1.7 minutes, respectively, in the vecuronium group.
Three patients experienced recurrent neuromuscular blockade, defined as a decrease in TOF ratio from 0.9 or higher to less than 0.8. These patients had all received low sugammadex doses and none suffered a clinical event attributable to the recurrence.
Four patients suffered serious adverse events, unrelated to the study drugs, including wound hemorrhage, laryngeal edema, convulsions, and bacterial meningitis. “Sugammadex seems equally effective for reversal of rocuronium-induced neuromuscular blockade whether anesthesia is maintained with propofol or sevoflurane,” the team said in Anesthesia and Analgesia.
Source: MedWire News
The putative excess risk for certain peri-operative complications in patients given beta blockers may be caused by the drugs increasing patients’ vulnerability to the effects of anemia, research suggests.
Peri-operative beta blockers are given to reduce patients’ risk for myocardial infarction, but previous research has raised the concern that this approach could also increase the risk for peri-operative stroke and mortality.
“We would suggest that acute surgical anemia may be a link between these two factors,” Scott Beattie and colleagues wrote in the journal Anesthesiology.
The researchers reviewed surgical records for 4387 noncardiac, nontransplant patients, 26% of whom received beta blockers within 24 hours of surgery. They matched patients who did and did not receive beta blockers by a propensity score estimating their probability of receiving a peri-operative beta blocker.
Within this subgroup of 827 patient pairs, 6.5% of patients given beta blockers versus 3.0% of controls met the primary composite outcome of myocardial infarction, nonfatal cardiac arrest, and in-hospital mortality. This equated to a 2.38-fold risk increase associated with beta blockade.
However, this risk increase was restricted to patients whose hemoglobin levels fell by at least 35% from baseline. Among these patients, the risk increase associated with beta blockade was 3.15-fold.
Richard Weiskopf said: “We cannot yet claim that we know the influence of hemoglobin in the cardiovascular and cerebrovascular events when beta-adrenergic antagonism is instituted before surgery, but Beattie et al give us a pathophysiologically plausible hypothesis.”
“Until better data are available, although beta-adrenergic antagonists seem to protect the myocardium of high-risk patients and may well be of lesser or no efficacy for patients at lesser risk, it would seem prudent to avoid those agents that substantially impair the cardiac response to acute severe anemia when that or substantial hemorrhage is anticipated.”
Doctors at Gartnavel Hospital in Glasgow have hit upon a novel idea to distract patients undergoing surgery by making them watch DVD movies at the operation table.
Dr Nick Pace, anaesthetist at Gartnavel, said that while patients do recover faster when given local or general anaesthesia, a number found it to be too stressful and needed to be calmed down after the operation.
The doctors tried to cut down the number of patients opting for anaesthesia by turning on music but found that the patients started to get distracted after listening to the music for some time.
Dr Pace then struck upon the idea of playing movies after a conversation with a friend and asked the engineers at the hospital to build a structure so that the DVD player could be held up over the operating table.
The International Anesthesia Research Society (IARS) has named Dr. Michael Roizen as Chair of the Executive Board of SAFEKIDS (Safety of Key Inhaled and Intravenous Drugs in Pediatrics).
SAFEKIDS, a public-private partnership between the FDA and the IARS, was launched as a long-term collaborative effort to address major gaps in scientific and clinical knowledge regarding safety for children who undergo anaesthesia and sedation each year.
Projects conducted under the auspices of SAFEKIDS will investigate diverse aspects of existing anaesthetics and their administration, as well as patient outcome. These projects aim to enhance the safety of current anaesthetics and drive the development of new drugs. The SAFEKIDS Executive Board has announced a $30m fundraising effort to support this research; Dr. Roizen will lead the fundraising activities.
“Making sure that drugs, and procedures using drugs, are safe and have a good chance of benefiting a patient's long-term health is the most important goal of medicine today,” said Dr. Roizen.
“The great news is that while anaesthesia-related studies are difficult to do, the FDA and hundreds of researchers are enthusiastic about doing them.”
Dr. Rob Sladen, Chair of the IARS Board of Trustees, said: “We are delighted that Mike Roizen is leading the SAFEKIDS Public-Private Partnership. He has earned the public's trust through his tireless advocacy of wellness and safe medical practice. This, along with his first-hand knowledge of anaesthetics and anaesthesia practice, uniquely qualifies him to lead SAFEKIDS and help the public understand the implications of ongoing research on the safety of anesthesia in infants and young children.”
Source: www.iars.org
Anaesthesia providers may soon be able to wear head-mounted displays that project patient data into their line of vision, letting them observe patients without looking away at vital signs monitors, according to research in the journal Anesthesia & Analgesia.
The wireless headset #151; connected to a battery pack and handheld computer contained in a backpack #151; receives data transmissions from patient monitors, displaying the information as a monochrome red image via a single transparent monocle in front of the right eye, according to the study. It’s a technology inspired by the heads-up displays used by pilots to notice unexpected changes to flight instrumentation faster than they would with traditional cockpit dials, say the researchers.
Anaesthesia heads-up displays could solve ergonomic issues associated with the location of patient monitors and would let providers perform such clinical tasks as drawing medications while continuously monitoring the patient, according to the study.
Source: www.outpatientsurgery.net
News Items
Newborn Baby Becomes World’s First Xenon-Treated Patient
A newborn baby has become the first in the world to receive xenon gas treatment, pioneered in Bristol, in a bid to prevent brain injury.
Riley Joyce had no pulse and was not breathing when he was first delivered by emergency Caesarean section at the Royal United Hospital, Bath.
He had a 50:50 chance of permanent brain injury and was transferred to St Michael’s Hospital, Bristol. His parents agreed to the experimental treatment and Riley is now doing well.
Every year in the UK more than 1,000 otherwise healthy babies born at full term die or suffer brain injury caused by a lack of oxygen or blood supply at birth.
The xenon technique was developed by Marianne Thoreson, professor of neonatal neuroscience at the University of Bristol, and Dr John Dingley, consultant anaesthetist at Swansea University’s School of Medicine.
Professor Thoreson said: “After seven days, Riley was alert, able to look at his mother’s face, hold up his head and begin to take milk.”
The professor has pioneered new treatments at the hospital since 1998 when she began cooling babies to reduce damage in the newborn brain.
However, cooling only partly reduces disability and does not prevent it in all babies.
She said: “Over the past eight years, we have shown in the laboratory that xenon doubles the protective effect of cooling on the brain. However we faced the challenge of how to safely and effectively deliver this rare and extremely expensive gas to newborn babies.”
Dr Dingley, who invented a machine to deliver the gas, said: “A key design feature of this machine is that it is very efficient, using less than 200ml of xenon per hour – less than the volume of a soft drinks can.
“Xenon is a precious and finite resource and difficult to extract so it can cost up to £30 a litre.
“As ventilated newborns breathe many litres of air per minute, any xenon-based treatment would be impossibly expensive without an economical delivery method.”
The device is now authorised for clinical trials and will be used on a minimum of 12 babies over the coming months in a feasibility trial before it can be used on a larger scale.
The study is being funded by Sparks, the children’s medical research charity, which has committed almost £800,000 to the team’s work.
Source: BBC
Nationwide Alert On Breathing Machines Issued To Hospitals
A nationwide alert has been issued to hospitals after a series of incidents involving artificial breathing machines that have harmed patients, it has been emerged.
The country’s medical devices watchdog warned about dangers arising from faulty or wrongly-used anaesthetic breathing systems.
In a medical devices alert, the Medicines and Healthcare Products Regulatory Agency (MHRA) said it “continues” to receive reports of patient harm because of the problems. These happen on average “less than five times” a year, a spokesman said.
“We are not aware of any device-related deaths in the past five years,” the watchdog added.
Overall, about 250 incidents are reported involving anaesthetic machines each year, the MHRA said, “usually related to the way the equipment is used rather than a fault in the device itself”.
In one case an anaesthetic breathing system was wrongly connected to the gas outlet of an anaesthetic machine.
When the patient started showing signs of distress, doctors wrongly interpreted it as bronchospasm, or tightening of the airways, and administered drugs.
By the time they realised there was a problem with the equipment, the patient suffered a collapsed lung, but survived thanks to the prompt action of the surgeons.
In its alert, the MHRA warned: “Whilst such equipment issues are uncommon, they should be considered as a matter of course when problems with patient ventilation occur.”
Source: UKPA
Dopamine ‘Increases Mortality In Cardiogenic Shock’
Dopamine is associated with more arrhythmias than is norepinephrine in patients with shock, and increases mortality in those with cardiogenic shock, shows a randomised trial.
“This study raises serious concerns about the safety of dopamine therapy,” said Daniel De Backer and colleagues in the New England Journal of Medicine.
The team randomly assigned 1679 patients with shock (62.2% septic, 16.7% cardiogenic, 15.7% hypovolemic) to receive dopamine 20 µg/kg/minute or norepinephrine 0.19 µg/kg/minute as first-line therapy to restore and maintain blood pressure. At 28 days, mortality rates were not significantly different between the groups, at 52.5% and 48.5% in the dopamine and norepinephrine groups, respectively.
But 24.1% of dopamine-treated patients developed arrhythmias, compared with just 12.4% of those given norepinephrine. Severe arrhythmias forced withdrawal of the study drug in 6.1% of the dopamine group compared with 1.6% of the norepinephrine group.
After day 28, dopamine-treated patients had fewer days where they did not need the study drug than those in the norepinephrine group, (11.0 vs 12.5), and where they did not require open-label vasopressors, (21.6 vs 14.2).
There were 280 patients with cardiogenic shock in the study. Among this subgroup, mortality was significantly more likely with dopamine than with norepinephrine, report the researchers.
“The exact cause of the increased mortality cannot be determined, but the early difference in the rate of death suggests that the higher heart rate with dopamine may have contributed to the occurrence of ischemic events.”
“Whatever the mechanism may be, these data strongly challenge the current American College of Cardiology – American Heart Association guidelines, which recommend dopamine as the first-choice agent to increase arterial pressure among patients who have hypotension as a result of an acute myocardial infarction.”
Repeated Anaesthesia In Children ‘Linked To Memory Impairment’ – Study
There is a link between repeated anaesthesia in children and memory impairment, according to new research from the Sahlgrenska Academy in Gothenburg, Sweden.
The study has been published in the Journal of Cerebral Blood Flow & Metabolism.
“Paediatric anaesthetists have long suspected that children who are anaesthetised repeatedly over the course of just a few years may suffer from impaired memory and learning,” said Klas Blomgren, professor at the Queen Silvia Children’s Hospital and researcher at the Sahlgrenska Academy.
“This is a theory that is also supported by foreign research.”
His research team discovered, by chance, a link between stem cell loss and repeated anaesthesia when working on another study. They wanted to find out what happens to the brain’s stem cells when exposed to strong magnetic fields, for example during an MRI scan. The study was carried out using rats and mice, and showed that while the magnetic fields did not have any tangible effects on the animals, the repeated anaesthesia did.
“We found that repeated anaesthesia wiped out a large portion of the stem cells in the hippocampus, an area of the brain that is important for memory,” said Blomgren.
“The stem cells in the hippocampus can form new nerve and glial cells, and the formation of nerve cells is considered important for our memory function.”
Their results could also be linked to impaired memory in animals as they got older. The effect was evident only in young rats or mice that had been anaesthetised, not when adult animals were anaesthetised. This may be because stem cells are more sensitive in an immature brain, even though there are fewer of them as we get older.
“Despite extensive attempts, we have not been able to understand exactly what happens when the stem cells are wiped out,” said Blomgren.
“We couldn’t see any signs of increased cell death, but are speculating that the stem cells lose their ability to divide.”
Another treatment that wipes out the brain’s stem cells is radiotherapy, which is used with cancer patients. Blomgren and his research team have previously used animal studies to show that physical activity after radiotherapy can result in a greater number of new stem cells and partly replace those that have been lost.
“What’s more, the new nerve cells seem to work better in animals that exercise. Now that we know this, we can come up with treatments that prevent or reverse the loss of ostem cells after repeated anaesthesia,” said Blomgren, who believes that the findings will lead to greater awareness of the problems and inspire further research into the reasons for the loss of stem cells.
Source: www.healthcanal.com
Capnography Improves Sedation Safety
Adding capnography to standard monitoring during emergency department sedation reduces hypoxia and provides forewarning of all hypoxic events, show results of a randomized trial.
Kenneth Deitch (Albert Einstein Medical Center, Philadelphia, Pennsylvania, USA) and colleagues say that the reduction in hypoxic events in their trial is “both statistically and clinically significant.”
In total, 132 patients were included in the study, which appears in the Annals of Emergency Medicine. During sedation with propofol (1.0 mg/kg, then 0.5 mg/kg as needed), all patients underwent monitoring with capnography, using the Capnostream 20, which records data every 5 seconds. But in one group, the physician was blinded to the capnography data.
Hypoxia was defined as an oxygen saturation level of less than 93%. This occurred in 17 (25%) of 68 patients with capnography – significantly fewer than in the blinded capnography group, in which 27 (42%) of 64 patients suffered hypoxia.
All instances of hypoxia, in both groups, were preceded by respiratory depression on capnography, defined as end tidal CO2 greater than 50 mmHg or more than 10% different from baseline, or loss of the waveform.
Physicians who were aware of the capnography data intervened to improve patients’ respiratory status more often than those who were blinded, at 35% versus 22% of instances.
Hypoxia developed a median of 60 seconds (range 5–240 seconds) after respiratory depression occurred.
“For many patients, the physicians had an ample amount of time to identify capnographic evidence of respiratory depression and intervene,” say Deitch et al.
“Conversely, it is possible that some incidences of hypoxia occurred so quickly after a corresponding capnographic change that the physicians could not respond rapidly enough to prevent them.”
Although 100% sensitive, capnography was only 64% specific – 32 of 76 patients who exhibited respiratory depression did not then develop hypoxia.
“Further research should address which specific capnographic changes are the most predictive of hypoxia,” conclude the researchers.
Source: Anaesthesia Now
Dispelling Misconceptions Associated With Anaesthesia Reduce Patient Anxiety Before Surgery
Eight-five per cent of patients who took part in a survey shortly after day surgery said that they had been anxious about receiving a general anaesthetic, according to research in the May issue of the Journal of Advanced Nursing.
17% of respondents said they were very or extremely anxious, 22% said they were quite anxious, 46% said they were a little anxious and 15% experienced no anxiety at all.
Key concerns included dying while asleep, not waking up after surgery, waking up during surgery and anxiety while waiting to go into surgery or arriving at the theatre door.
“Our survey underlines the importance of patients receiving planned and timely information about anaesthesia, prior to the day of surgery, in order to limit their anxiety” says Dr Mark Mitchell, senior lecturer in the Faculty of Health and Social Care at the University of Salford, UK.
“This should include information about how anaesthesia is managed, the notion of carefully controlled and supervised anaesthesia and dispelling misconceptions associated with general anaesthesia.”
Patients scheduled for elective surgery in three day surgery units in England were invited to take part in the survey and 460 patients - a response rate of 37% - completed the questionnaire within 24-48 hours of surgery.
The patients who took part were aged between 18 and 75, with an average age of 46, and 59% were female. The majority had undergone gynaecological, general, orthopaedic, urological and ear, nose and throat surgery.
Patients were asked to indicate their anxiety levels about 24 different issues. This showed that:
- The top 3 concerns that made patients anxious were the thought of not waking up (26%), dying while asleep (25%) and waking up during surgery (20%).
- When the researchers combined all the patients who were anxious, the top 5 concerns were: waiting for their turn in theatre (59%), the thought of arriving at the theatre door (56%), dying while asleep or not waking up afterwards (both 48%) and waking up during surgery (46%).
- Forty-one per cent said that they didn’t like the thought of having to put their trust in strangers and 12% felt very anxious about this.
- Anxiety levels were lowest when it came to interactions with medical staff and the support of a partner or friend. 30% felt very calm about the anaesthetist explaining the procedure, 28% about the anaesthetist visiting and 17% about the nurse explaining the procedure. 26% felt very calm about having a friend or partner with them during recovery.
Dr Mitchell says, “Our survey shows that more attention needs to be paid to the psychological aspects of the patients care.
“The formal and timely provision of information about the planned surgery - together with a patient-centred approach to the provision of information, such as pre-assessment clinics - are vital first steps.
“It is clear from our study that many patients do not know how the anaesthesia process works and that this has led to misconceptions about, for example, waking up during surgery. It is vital to tackle these misconceptions if we are to reduce patient anxiety before day surgery.”
Source: Journal Of Advanced Nursing
New Guidelines For Nerve Block Use In Patients Cause Controversy
New guidelines from the American Society of Regional Anesthesia and Pain Medicine aim to clarify the appropriate use of nerve blocks in patients.
But it has caused controversy over the safety of antithrombotic agents in some cases, and according to one expert, could raise unnecessary concerns about some patients, especially those receiving thromboprophylaxis who undergo deep plexus and peripheral blocks.
The 37-page guidelines, which update ASRA recommendations published in 2003, address a wide range of situations, from women who are pregnant or in labour to patients undergoing plexus or peripheral blockade.
But, Jacques Chelly, professor and vice chair of clinical research in the Department of Anaesthesiology at the University of Pittsburgh Medical Center, objected to the way the new guidelines lump deep plexus and peripheral nerve blocks with neuraxial procedures in patients receiving thromboprophylaxis. In particular, the recommendations call for large gaps between when clot-preventing drugs are stopped and started and when the blocks are performed.
Guidelines often have the effect of narrowly defining practice patterns because clinicians, fearing malpractice suits, are loath to stray from the recommendations, Dr. Chelly said. “It is already difficult enough for anesthesiologists who perform blocks to be the first to be blamed for any postoperative nerve injury, even when they are surgically related, without adding unbalanced recommendations related to the risk for major bleeding in patients receiving thromboprophylaxis and deep plexus and peripheral nerve blocks.”
The 2010 guidelines state that patients receiving low-molecular-weight heparin (LMWH) should not be given other drugs that affect hemostasis, such as standard heparin, antiplatelet agents or dextran. The guidelines also call for anaesthesiologists to discuss LMWH therapy with surgeons prior to initiating treatment, and to delay the drugs for 24 hours after surgery. They call for at least a 10- to 12-hour delay between the last standard LMWH dose and needle placement for anaesthesia, or at least a 24-hour delay for a higher LMWH dose.
One of the main goals is to reduce the occurrence of spinal hematoma, following recent epidemiological data suggesting the frequency of the complication is increasing and may be as high as one in 3,000 in some populations.
The guideline authors, led by Terese Horlocker, professor of anaesthesiology and orthopaedics at Mayo Clinic, said recommendations for neuraxial techniques also should apply to deep plexus and peripheral nerve blocks. These procedures include lumbar plexus, lumbar sympathetic and paravertebral blocks, Dr. Horlocker said.
Dr. Chelly noted that the new guidelines acknowledge the series his group published in 2008 on 670 patients who received warfarin and continuous lumbar plexus blocks, but did not review another article involving 6,935 peripheral blocks in more than 3,500 patients receiving thromboprophylaxis without interruption; none of these experienced major bleeding.
“The consensus does not distinguish between the therapeutic and thromboprophylaxis indications of anticoagulants,” Dr. Chelly said.
“This distinction is important because, first, the doses recommended to treat DVT and pulmonary embolism are higher than those recommended for thromboprophylaxis; second, most patients who benefit from peripheral nerve blocks receive thromboprophylaxis, meaning lower dosing of LMWH; and third... evidence supporting the recommendations that deep blocks should be treated like neuroaxial blocks is lacking.”
The authors only reported 13 cases of major bleeding following blocks in patients receiving antithrombotic therapy. Of those, a minority was related to the combinations of thromboprophylaxis, including aspirin and continuous nerve blocks and in most cases, the placement of the blocks was associated with major trauma. “In our practice, we have not interrupted the thromboprophylaxis when removing perineural catheters for more than 15 years and have not observed any major bleeding complications,” Dr. Chelly said.
Dr. Horlocker said the additional data would not affect the ASRA recommendations. “Only a very small proportion of patients received a continuous lumbar plexus block - that is, a deep block - and who were on a regimen that would perhaps preclude a block.”
“That is, there were just 23 patients receiving twice-daily enoxaparin and another 193 receiving fondaparinux. So this series will not change the ASRA guidelines, because we need larger numbers and more rigorous study of the risk–benefit ratio.”
Source: Anesthesiology News
Intraoperative Awareness Patients Suffer From Stress Disorder
Nearly two-thirds of patients who experienced intraoperative awareness suffered from post-traumatic stress disorder five years after their surgeries, according to researchers who followed up with patients in Australia, New Zealand and Hong Kong.
“Long-term psychological follow-up should be offered to patients who report awareness regardless of their early postoperative psychological state,” suggest the researchers, who published their findings in the March issue of Anesthesia & Analgesia.
The research team surveyed patients who’d experienced awareness during a clinical trial of 2.463 surgical patients designed to study the efficacy of bispectral monitoring. Seven of the 13 patients who’d experienced awareness were still alive, and 5 of them reported symptoms of PTSD, according to the article.
It's not certain, however, that anesthesia awareness caused the PTSD in each case, writes George Mashour, MD, PhD, of the University of Michigan Medical School in an accompanying editorial. The patients in the trial were undergoing potentially stressful high-risk surgeries and may have suffered from other illness-related factors. “Medical events, such as myocardial infarction, can be associated with PTSD,” he writes.
Regardless, concludes Dr. Mashour, the high rate of PTSD “reinforces the need for preventing intraoperative awareness.”
Source: www.outpatientsurgery.net
Critically Ill Patients ‘Less Likely to Die’ If Treated In ICU with Daily Rounds
Critically ill patients are less likely to die if they are treated in an intensive care unit (ICU) that benefits from daily rounds by a multidisciplinary team, say US researchers.
In units with low-intensity staffing, the presence of a multidisciplinary team improved patient outcomes nearly to those achieved in ICUs with high-intensity physician staffing, they report in the Archives of Internal Medicine.
“These results suggest that in hospitals without high-intensity physician staffing, multidisciplinary rounds are likely to improve patient outcomes,” said Jeremy Kahn (University of Pennsylvania School of Medicine) and colleagues.
The team studied outcomes of 107,324 patients admitted to 112 ICUs in Pennsylvania. The overall mortality rate was 18.3%.
Multidisciplinary care, where patients were assessed by a physician, nurse, and other healthcare professionals, such as a clinical pharmacist or respiratory therapist, was associated with an overall 16% reduction in patient mortality, after accounting for patient and hospital variables.
The highest risk for death, after accounting for confounders, occurred in ICUs with low-intensity physician staffing and no multidisciplinary rounds. The presence of a multidisciplinary team decreased mortality risk by 12%, which was almost in line with the 16% reduction achieved by high-intensity staffing.
The combination of high-intensity staffing and a multidisciplinary team was associated with the largest reduction in mortality risk, of 22%.
In subanalyses, the benefits of multidisciplinary care and high-intensity staffing were consistent for patients with sepsis, those requiring mechanical ventilation, and those in the highest quartile of severity of illness.
“Workforce analyses suggest that these are not enough intensivists to meet demand, and as a consequence only a minority of ICUs in the USA are staffed by trained intensivists,” said Kahn.
“Directors of ICUs report that lack of enough trained intensivists is a key barrier to implementing an intensivist model of care.”
“Our study shows that hospitals without the ability to implement high-intensity physician staffing can still achieve significant mortality reductions by implementing a multidisciplinary, team-based approach,” he concluded.
Source: MedWire News
ASA Advises Members On Monitoring Propofol For Upper Endoscopies
The American Society of Anesthesiologists (ASA) is advising its members not to administer the sedative propofol for upper endoscopies without the aid of a device to detect changes in the amount of carbon dioxide the patient is exhaling.
Capnography monitors are widespread in hospitals but are less common in endoscopy suites and other ambulatory settings where propofol often is used. As a result, the impact of the recommendation, which carries no legal authority, likely will be felt disproportionately by clinicians who provide sedation outside the hospital setting.
The new policy states: “Monitoring for exhaled carbon dioxide should be considered during endoscopic procedures in which sedation is provided with propofol alone or in combination with opioids and/or benzodiazepines, and especially during these procedures on the upper gastrointestinal tract. Careful attention to airway management must be provided during endoscopic retrograde cholangiopancreatography (ERCP) procedures performed in the prone position where ventilatory monitoring, airway maintenance and resuscitation may be especially difficult.”
This policy emerged from the 2009 annual meeting of the ASA, when the group’s 400-member house of delegates approved the recommendation. The wording of the statement differs slightly from a previous draft, which stated, “tracheal intubation and general anesthesia should be strongly considered during endoscopic procedures where monitoring, airway maintenance and resuscitation may be difficult.”
Jennifer Gremmels, a spokeswoman for the ASA, said the new recommendation “passed easily” by voice vote and did not draw enough dissent to force a ballot.
Hector Vila, chair of the ASA’s ambulatory surgery committee, said the new monitoring guidance for propofol sedation was the strongest yet from any medical body. The policy focuses on upper endoscopies, as opposed to procedures in the lower gastrointestinal tract, “because that’s where the data are,” he said. Although it’s not entirely clear why propofol appears riskier in patients undergoing upper endoscopies, Dr. Vila said the sharing of the patient’s airway by the gastroenterologist and the anaesthesiologist seems to be a key factor.
US Anaesthetist Clifford Gevirtz expressed misgivings about the ASA statement. “I haven’t seen any convincing data that this is actually going to affect the overall rate of complications. This is the same problem [we’ve seen] with pulse oximetry: We think it is a good thing, but the actual science proving that it is, isn’t there. This is a consensus statement without scientific evidence backing it up.”
“One problem with proclamations from the ASA House of Delegates is that they have at times either not been evidence-based or have failed to describe the supporting evidence,” said Douglas Rex, distinguished professor of medicine, Indiana School of Medicine.
As for office-based anaesthestists, Dr. Gevirtz said, “I hope most will follow the recommendations of the ASA. I just wish they based it on science and not gut feelings. The standard of care here is going to be a bit nebulous because of the phrasing they used,” he added, possibly to build in a little liability wiggle room. “But I really think that the sense of the society is that there is very little downside in monitoring, and it just may save a life or two.”
Source: MedWire News
Carbon Monoxide Levels In Children’s Blood Increases During Anaesthesia
Doctors at Children’s National Medical Center have found that carbon monoxide levels in the blood of young children increase during routine general anaesthesia.
Anaesthetists have found for the first time that, under certain circumstances, infants and children may be exposed to carbon monoxide during routine anesthesia resulting in a rise in the carbon monoxide levels in the child’s blood.
Because carbon monoxide can be generated as a byproduct of anaesthesia, anaesthetists world-wide use specific precautions to prevent and limit its production, according to Richard Levy, Chief of Cardiac Anesthesiology, at Children’s National. Dr. Levy’s team identified the conditions in which carbon monoxide may be inhaled during anaesthesia.
The first study demonstrated that carbon monoxide detected in the breathing circuit correlated with the increase in blood levels in children 2 years and older. The study included 15 patients between 4 months and 8 years.
The second study identified that the patient’s own exhaled carbon monoxide may be “re-breathed” during low-flow anesthesia – the current standard of care – where fresh gas flows more slowly into the circuit, rather than rapidly.
“The main goal is to provide the safest environment for young patients who require surgery,” said Dr. Levy. “We have identified tangible ways to reduce the risk of carbon monoxide exposure, and our hope is that these changes will be implemented internationally.”
Much remains unknown about the effects of low-dose carbon monoxide exposure on the developing brain. Recent studies have suggested there may be a link to hearing impairments. Though there is more research to be done to determine these impacts, Dr. Levy recommends two changes that will eliminate the risk of carbon monoxide exposure in children.
In the anaesthesia machine, use carbon dioxide absorbents that lack strong metal alkali and do not degrade inhaled anesthetics (avoids CO production risk) and avoid of low-flow anaesthesia (avoids CO re-breathing risk)
Although the sample size is small, the results are compelling and Dr. Levy believes changes should be implemented.
Source: http://insciences.org
Patients In Lower Socioeconomic Group Face Death Sooner After Heart Surgery
A study at the Department of Cardiothoracic Anesthesia at Cleveland, United States, suggests that people in the lower socioeconomic levels may face death within five to ten years from the time of heart surgery, irrespective of race or gender.
The study analyzed a total of 23,330 people who survived their heart surgeries between the years 1995 and 2005. Out of this number, 15,156 were white men, 6,932 white women, 678 black men and 564 black women. The study elaborated that each drop in socioeconomic position had a corresponding ‘dose-dependent’ decrease in the long-term survival rate.
Scientist Colleen G. Koch, cardiac anaesthestist and vice chair for research and education in the Department of Cardiothoracic Anesthesia at the Cleveland Clinic in Cleveland, Ohio said: “We were surprised that consistently and pervasively, through every way of looking at the data, it turns out this isn’t about skin color or gender. It’s about being poor.”
After adjusting to the existing risk factors such as high blood pressure and diabetes, patients from the lowest socioeconomic position seemingly had a 19 to 26 percent higher chance of dying within five to ten years of surgery. These results were generated in comparison to those patients that had undergone surgery but did not belong to the low socioeconomic class.
Patients in the lower socioeconomic classes reportedly suffered from severe atherosclerosis, cardiovascular diseases, prior heart attacks, left ventricular dysfunction and heart failures. These patients seemingly also suffered from hypertension, prior stroke, and peripheral artery diseases. They were also treated for diabetes, were smokers and had severe obstructive pulmonary disease.
The research revealed that a large number of black men and women participants belonged to the lower socioeconomic classes rather than white men and women. To determine the socioeconomic positions, scientists investigated six categories of U.S Census data linked to patients’ neighborhood which included heads like median household income, educational level and median home value. Patients’ socioeconomic factors and risk-adjusted health outcomes after six-months of surgery were also examined. The median follow-up was conducted 5.8 years later.
The team kept a tab on heart bypass and valve surgery patients because of the known risk factors and the results garnered from the usual heart operations.
Koch remarked that. “There’s something in particular about the follow-up period in the 10 years afterward that’s making them more likely to die.”
The death rate among these patients from lower socioeconomic levels was not that prominent when the patients stayed-on in the hospital following surgery. According to Koch lack referrals to cardiac rehabilitation programs after surgery, educational barriers and financial obstacles could all contribute to poor health outcomes in follow-up years.
The mortality rate among these patients may be improved by working on the link to primary prevention, identifying risk factors, delivering secondary prevention and increasing access to long-term interventions.
The findings of the research have been a part of the American Heart Association journal.
Issue: June 2010
