On the basis of the literature, the development of war anaesthesiology is reviewed from the first war anaesthesia in 1847 until the present day. For nearly 100 years, ether was the main anaesthetic but, after the second world war, this was replaced by ketamine (Ketalar) which may be administrated by a simple injection or infusion. Under field conditions, the use of inhalation anaesthesia was rendered possible after the introduction of mobile mini-vaporizer which function according to the "draw over" principle and may thus employed without access to a flow of fresh gas. The anaesthetic most commonly is a combination of halothane and trichlorethylene. Following a review of the advantages and disadvantages of ketamine as compared with inhalation anaesthesia under field conditions, it is concluded that ketamine is preferable in mobile units while larger and stationary units should have the possibility for employing current methods of anaesthesia also. A proposal is presented for standard anaesthesia in small units in situations in war and catastrophes.
AIM: To examine the effectiveness and safety of the sedative agents used in the emergency department following the introduction of ketamine as an agent for procedural sedation METHODS: A 2-year prospective audit of sedation practice was undertaken. This specifically examined the rationale behind a doctor's choice of sedative agent, the depth of sedation achieved, adverse events and the time taken to regain full orientation. RESULTS: 210 patients were included of whom 85 (40%) were given ketamine, 107 (51%) midazolam and 18 (9%) propofol. The median time to full orientation was 25 min for ketamine, 30 min for midazolam and 10 min for propofol. Complications occurred in 15.9% of sedations overall (14.6% of those given ketamine, 15.8% given midazolam and 22.2% given propofol). Apnoea and hypoxia most often occurred with midazolam and propofol, while hypertension and hypertonicity were encountered more frequently with ketamine. In addition, 19.5% of patients given ketamine suffered the re-emergence phenomenon. The association between deep sedation with no response to pain and adverse events encountered with midazolam does not occur with ketamine. CONCLUSIONS: Ketamine is both safe and effective and compares favourably with midazolam as an agent for procedural sedation in the emergency department. Although the re-emergence phenomenon occurred, no psychological sequelae were encountered after return to full orientation. Ketamine may be particularly useful in groups of patients at high risk of adverse effects with midazolam.
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Comment In: Emerg Med J. 2009 May;26(5):38919386889
Section of Anesthesiology and Emergency, Department of Clinical Sciences, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences, Uppsala, Sweden. asa_fahlman@hotmail.com
Capture and anesthesia with medetomidine-ketamine were evaluated in free-ranging wolverines (Gulo gulo) immobilized for marking with radiocollars or intraperitoneal radiotransmitters in Norrbotten, Sweden, during early June 2004 and 2005. Twelve juvenile wolverines were captured by hand and injected with 0.14 +/- 0.03 mg/kg (mean +/- SD) medetomidine and 7.5 +/- 2.0 mg/kg ketamine. Twelve adult wolverines were darted from a helicopter or the ground, or captured by hand. Adults received 0.37 +/- 0.06 mg/kg medetomidine and 9.4 +/- 1.4 mg/kg ketamine. Arterial blood samples were collected between 15 min and 30 min and between 45 min and 60 min after drug administration and immediately analyzed for selected hematologic and plasma variables. Hyperthermia was recorded initially in one juvenile wolverine and 11 adults. Rectal temperature, heart rate, and lactate decreased significantly during anesthesia, whereas hemoglobin oxygen saturation, pH, partial pressure of arterial carbon dioxide, and base excess increased. Adult wolverines darted from a helicopter had a significantly higher rectal temperature, higher glucose and hematocrit values, and a lower heart rate than juveniles captured by hand. Impaired arterial oxygenation was evident in all wolverines. This study provides baseline data on physiologic variables in adult and juvenile wolverines captured with different methods and anesthetized with medetomidine-ketamine.
OBJECTIVE: To provide reliable, effective immobilization for Weddell seals under extreme field conditions using an injectable ketamine/midazolam combination. STUDY DESIGN: Observational study. ANIMALS: Thirty adult Weddell seals (12 male, 18 female) in Erebus Bay, Antarctica, body mass (mean +/- SD) 412 +/- 47 kg, aged 9-27 years. METHODS: Seals were immobilized with a target dose of 2 mg kg(-1) ketamine hydrochloride and 0.1 mg kg(-1) midazolam hydrochloride (IM), based on visually estimated body mass. When required, maintenance doses were administered at a target of 0.5 mg kg(-1) ketamine hydrochloride and 0.025 mg kg(-1) midazolam hydrochloride (IV). RESULTS: Complete immobilization was achieved in 33 of 40 injections (14 of which were repeat events on the same individual). Time to immobilization averaged 12 +/- 4 minutes, with a duration of initial immobility of 38 +/- 19 minutes. Total immobilization time varied by handling protocol, including condition assessment and muscle biopsy (Protocol 1, 60 +/- 13 minutes), condition assessment and instrument attachment (Protocol 2, 154 +/- 13 minutes), and condition assessment, muscle biopsy and instrument retrieval (Protocol 3, 48 +/- 8 minutes). Overall, a total immobilization time of 114 +/- 60 minutes was accomplished with 4 +/- 4 maintenance doses, and an average recovery time of 36 +/- 17 minutes. Most effects of the anesthetic combination were unrelated to mass, age, sex or total body fat. However, leaner seals had longer duration of initial immobility (% and kg total body fat) and recovery times (kg fat). Apnea events were uncommon and treated effectively with doxapram. No animals died. CONCLUSIONS AND CLINICAL RELEVANCE: Reliable and effective field immobilization of Weddell seals was accomplished with a low dose of ketamine hydrochloride and midazolam hydrochloride, utilizing IM injection initially and IV maintenance methods.
Current practice and tolerance for risk in performing procedural sedation and analgesia on children who have not met fasting guidelines: a Canadian survey using a stated preference discrete choice experiment.
The objectives were to explore the tolerance of pediatric emergency medicine (PEM) physicians for risk in choosing when to perform procedural sedation and analgesia (PSA) and to describe adherence to preprocedural fasting guidelines and factors affecting the physicians' decisions.
A survey of Canadian PEM physicians who perform PSA was conducted. Respondents were asked about their PSA practices. Risk tolerance was assessed using an economics-based stated preference elicitation method called a discrete choice experiment (DCE). Using a hypothetical clinical situation of a healthy child needing PSA, three fasting scenarios (ingestion of full meal
Pain is a common condition among prehospital patients. The present study is designed to determine whether adding low-dose ketamine as additional analgesia improves the pain/nausea scores and hemodynamic parameters compared to morphine sulphate alone among patients with bone fractures.
Prospective, prehospital clinical cohort study. Twenty-seven patients were included with acute pain. Eleven patients received morphine sulphate 0.2 mg/kg (M-group) and 16 patients received morphine sulphate 0.1 mg/kg combined with 0.2 mg/kg ketamine (MK-group). Scores for pain, nausea, sedation (AVPU) and the haemodynamic parameters (systolic blood pressures (BP), heart rate (HR) and peripheral oxygen saturation (SpO2) were recorded at rescue scene before the start of analgesia and subsequently to admission at hospital.
Mean treatment time 46 +/- 17 minutes in the M-group and 56 +/- 11 minutes in the MK-group, respectively (ns). Mean doses of morphine sulphate in the M-group were 13.5 +/- 3.2 mg versus 7.0 +/- 1.5 mg in the MK-group. The mean additional doses of ketamine in the MK-group were 27.9 +/- 11.4 mg. There were significantly differences between the M- and the MK-group according to NRS scores for pain (5.4 +/- 1.9 versus 3.1 +/- 1.4) and BP (134 +/- 21 mmHg versus 167 +/- 32 mmHg) at admission at hospital, respectively (P
PURPOSE: To determine the effect of several common general anesthetics on intraocular pressure (IOP) after experimental aqueous outflow obstruction in the rat. METHODS: A single episcleral vein injection of hypertonic saline was used to sclerose aqueous humor outflow pathways and produce elevated IOP in Brown Norway rats. Animals were housed in either standard lighting or a constant low-level light environment. Awake IOPs were determined using a TonoPen (Mentor, Norwell, MA) immediately before induction of anesthesia by either isoflurane, ketamine, or a mixture of injectable anesthetics (xylazine, ketamine, and acepromazine). For each anesthetic, IOPs were measured immediately after adequate sedation (time 0) and at 5-minute intervals, up to 20 minutes. RESULTS; Awake IOPs ranged from 18 to 52 mm Hg. All anesthetics resulted in a statistically significant (P:
To determine the effectiveness and safety of procedural sedation and analgesia (PSA) in a Canadian community emergency department (ED) staffed primarily by family physicians and to assess the role of capnometry monitoring in PSA.
One hundred and sixty (160) consecutive procedural sedation cases were reviewed from the ED of a rural hospital in Huntsville, Ont. The ED is mainly staffed by family physicians who have received in-house training in PSA. Safety and effectiveness measures were extrapolated from a standardized PSA form by a blinded research assistant.
The mean age of the patient population was 33.6 years (standard deviation = 23.6). Fifty-four percent of the patients were male, and 33% of the cases were pediatric. PSA medications included propofol (84%), fentanyl (51%) and midazolam (15%), and the procedural success rate was 95.6%. The adverse event (AE) rate was 18% and included apnea (10%), inadequate sedation (3%), bradycardia (2%), desaturation (1%), hypotension (1%) and bag-valve-mask use (1%). In those aged > or = 65 years there was a greater incidence of apnea. There were no episodes of emesis and there were no intubations. A modified jaw thrust manoeuvre was used in 23% of the cases. I the 64% of cases where capnometry was used, there was no association between its use and any AE measures.
Procedural sedation was safe and effective in our environment. Capnometry recording did not appear to alter outcomes, although the data are incomplete.
Two thousand one hundred consecutive administrations of ketamine as an anaesthetic agent are reviewed. On the basis of the experience described, the authors assess that this agent could be used with safety in the average patient presenting for surgery and that it would be likely to suffice as the sole anaesthetic agent in 40% of such cases but would require supplementation by other anaesthetic agents in the remaining 60% of cases. They recommend it as being particularly useful in children submitting to dental surgery as it can be used without sedative premedication and permits of rapid recovery.
Immobilization of Norwegian reindeer (Rangifer tarandus tarandus) and Svalbard Reindeer (R. t. platyrhynchus) with medetomidine and medetomidine-ketamine and reversal of immobilization with atipamezole.
The sedative action of medetomidine (-ketamine) was studied in 12 captive Norwegian semidomesticated reindeer (NR), including 4 newborn calves, and in 7 free-living Svalbard reindeer (SR). Medetomidine, with or without ketamine, caused effective, reliable immobilization in NR. Doses of 50-200 micrograms/kg medetomidine alone or 30-125 micrograms/kg medetomidine combined with greater than or equal to 300 micrograms/kg ketamine induced complete immobilization, good muscle relaxation and persistent, deep sedation with little respiratory depression in NR; SR required higher doses. Atipamezole successfully antagonized medetomidine (-ketamine) resulting in rapid and persistent reversal of immobilization in all cases (NR and SR). Both medetomidine and atipamezole had wide safety margins and no conspicuous lasting side effects after reversal.
