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Introduction: For surgery on the upper extremity, the anaesthetist often has a choice between regional anaesthesia (RA) and general anaesthesia (GA). We sought to investigate the possible differences between RA and GA after upper extremity surgery with regard to postoperative patient comfort. Methods: This is a retrospective observational study that was performed at an acute care secondary referral centre. One hundred and eighty-seven procedures involving orthopaedic surgery on the upper extremity were included. The different groups (RA and GA) were compared regarding the primary outcome variable, length of stay in Postanaesthesia Unit, and secondary outcome variables, opioid consumption and nausea treatment. Results: RA was associated with significantly shorter median length of stay (99 versus 171 minutes). In the GA group, 32% of the patients received opioid analgesics and 21% received antiemetics. In the RA group, none received opioid analgesics and 3% received antiemetics. Conclusion: In this observational study, RA was superior to GA for surgery of the upper extremity regarding Postanaesthesia Care Unit length of stay, number of doses of analgesic, and number of doses of antiemetic administered.

Background: Self-Inflating Resuscitation Bags (SIRB) are common and essential tools in airway management and ventilation. They are often used in resuscitation and emergency anaesthesia outside the operating theatre. There is a common notion that all SIRBs applied with a tight sealed mask will deliver close to 100 % oxygen during spontaneous breathing. The aim of the study was to measure the oxygen delivery of six commonly used SIRBs in a mechanical spontaneous breathing adult in vitro model.

Methods: Three SIRBs of each of the six models were evaluated for oxygen delivery during simulated breathing with an adult mechanical lung. The test was repeated three times per device (54 tests in total). The breathing profile was fixed to a minute volume of 10 L/min, a tidal volume of 500 mL and the SIRBs supplied with an oxygen fresh gas flow of 15 L/min. The fraction of delivered oxygen (FDO2) was measured over a three-minute period. Average FDO2 was calculated and compared at 30, 60 and 90 s.

Results: At 90 s all models had reached a stable FDO2. Average FDO2 at 90 s; Ambu Oval Plus 99,5 %; Ambu Spur II 99,8 %; Intersurgical BVM Resuscitator 76,7 %; Laerdal Silicone 97,3 %; Laerdal The Bag II 94,5 % and the O-Two Smart Bag 39,0 %. All differences in FDO2 were significant apart from the two Ambu models.

Conclusions: In simulated spontaneous breathing, four out of six (by Ambu and Laerdal) Self-Inflating Resuscitation Bags delivered a high fraction of oxygen while two (Intersurgical and O-two) underperformed in oxygen delivery. These large variations confirm results reported in other studies. It is our opinion that underperforming Self-Inflating Resuscitation Bags might pose a serious threat to patients’ health if used in resuscitation and anaesthesia. Manufacturers of Self-Inflating Resuscitation Bags rarely provide information on performance for spontaneous breathing. This poses a challenge to all organizations that need their devices to deliver adequate oxygen during spontaneous breathing.

BACKGROUND: Trauma and its complications contribute to morbidity and mortality in the general population. Trauma victims are susceptible to acute respiratory distress syndrome (ARDS) and sepsis. Polymorphonuclear leucocytes (PMNs) are activated after trauma and there is substantial evidence of their involvement in the development of ARDS. Activated PMNs release heparin-binding protein (HBP), a granule protein previously shown to be involved in acute inflammatory reactions. We hypothesised that there is an increase in plasma HBP content after trauma and that the increased levels are related to the severity of the trauma or later development of severe sepsis and organ failure (ARDS).

METHODS AND MATERIAL: We investigated HBP in plasma samples within 36 h from trauma in 47 patients admitted to a level one trauma centre with a mean injury severity score (ISS) of 26 (21-34). ISS, admission sequential organ failure assessment (SOFA) and Acute Physiology and Chronic Health Evaluation (APACHE) II scores were recorded at admission. ARDS and presence of severe sepsis were determined daily during intensive care.

RESULTS: We found no correlation between individual maximal plasma HBP levels at admission and ISS, admission SOFA or APACHE II. We found, however, a correlation between HBP levels and development of ARDS (P = 0.026, n = 47), but not to severe sepsis.

CONCLUSION: HBP is a potential biomarker candidate for early detection of ARDS development after trauma. Further research is required to confirm a casual relationship between plasma HBP and the development of ARDS.

BACKGROUND: The increased vascular permeability seen after burn contribute to morbidity and mortality as it interferes with organ function and the healing process. Large efforts have been made to explore underlying pathophysiological mechanisms that generate increased vascular permeability after burns. Many different substances have been proposed as mediators of which histamine, serotonin and oxygen radicals are claimed most important. However, no specific blocker has convincingly been shown to be clinically effective. Early work has claimed increased histamine plasma-concentrations in humans after burn and data from animal models pointed at histamine as an important mediator. Modern human clinical studies investigating the role of histamine as a mediator of the generalized post burn increase in vascular permeability are lacking.

METHOD: We examined histamine turnover by measuring the urinary excretion of histamine and methyl histamine for 48 h after burns in 8 patients (mean total burn surface area 24%).

RESULTS: Over time, in this time frame and compared to healthy controls we found a small increase in the excretion of histamine, but no increase of its metabolite methylhistamine.

CONCLUSION: Our findings do not support that histamine is an important mediator of the increased systemic vascular permeability seen after burn.

Absorption of irrigating fluid is a well-known complication of endoscopic surgeries, such as transurethral resection of the prostate and transcervical endometrial resection (TCER). Irrigating fluid is used to distend the hollow organ and allows the surgeon to visualize the operating field. Traditional monopolar diathermy requires irrigating fluid to be electrolyte free, which is unphysiological and therefore elicits various symptoms when absorbed.(1-4) In recent years, endoscopic resections have often been conducted with a bipolar resectoscope, which allows crystalloid fluid to be used for irrigation. The symptoms, hemodynamic effects, and biochemical changes that arise from rapid inadvertent overload of crystalloid fluid in clinical settings are not as well known as those due to overload of electrolyte-free fluid. Further, current guidelines may be interpreted as that 2500-ml resorption of saline could be accepted.(5) Therefore, we describe two patients who absorbed isotonic saline during TCERs performed under general anesthesia. The second one (case B) probably was further complicated by a venous gas embolus.

Increased vascular permeability and oedema formation constitute a major clinical challenge following burns. Several clinical studies show that leukocytes are systemically activated following burns. Neutrophils have the capability to increase vascular permeability via mechanisms thought to involve the release of heparin binding protein (HBP). We hypothesised that HBP is elevated in plasma after major burns due to a systemic inflammatory response and investigated plasma-HBP concentrations in 10 severely burned patients daily for 1 week following the burn. Five-fold higher levels in plasma-HBP concentration compared to a control group were detected on the first day after injury, followed by a steep reduction in the time-period that corresponds to the last part of the hyperpermeability phase. These data are in accordance with the hypothesis that HBP may function as a mediator of the early burn-induced increase in vascular permeability, and call for further studies to confirm a possible cause-and-effect relationship between HBP and oedema formation following burns.

Pain is a problem that often has to be addressed in the prehospital setting. The delivery of analgesia may sometimes prove challenging due to problems establishing intravenous access or a harsh winter environment. To solve the problem of intravenous access, intranasal administration of drugs is used in some settings. In cases where vascular access was foreseen or proved hard to establish (one or two missed attempts) on the scene of the accident we use nasally administered S-Ketamine for prehospital analgesia. Here we describe the use of nasally administered S-Ketamine in 9 cases. The doses used were in the range of 0,45-1,25 mg/kg. 8 patients were treated in outdoor winter-conditions in Sweden. 1 patient was treated indoor. VAS-score decreased from a median of 10 (interquartile range 8-10) to 3 (interquartile range 2-4). Nasally administered S-Ketamine offers a possible last resource to be used in cases where establishing vascular access is difficult or impossible. Side-effects in these 9 cases were few and non serious. Nasally administered drugs offer a needleless approach that is advantageous for the patient as well as for health personnel in especially challenging selected cases. Nasal as opposed to intravenous analgesia may reduce the time spent on the scene of the accident and most likely reduces the need to expose the patient to the environment in especially challenging cases of prehospital analgesia. Nasal administration of S-ketamine is off label and as such we only use it as a last resource and propose that the effect and safety of the treatment should be further studied.

BACKGROUND: Patients with burns are susceptible to organ failure, and there is indirect evidence that leukocytes may contribute to this process. They may change the expression of cell-surface receptors after certain stimuli, for example, the burn. We therefore aimed to assess the changes induced by the burn in the expression of leukocyte cell-surface receptors CD11b, CD14, CD16, and CD62L on the surface of PMNs and monocytes. We also wanted to examine the dynamics of this activation during the first week after the burn, and to relate it to the size of the injury.

METHODS: Ten patients with burns of >15% (TBSA) were included in the study. Blood samples were collected on arrival and every consecutive morning during the first week. Healthy volunteers acted as controls.

RESULTS: PMN CD11b expression was increased. The extent of PMN CD11b expression correlated negatively to the size of the full thickness burn. Monocyte CD14 expression increased initially but there was no relation to the size of the burn. PMN CD16 expression decreased initially during the first days and the decrease was related to burn size. CD62L did not vary depending on the burn in either PMN or monocytes during the first week after the burn.

CONCLUSION: This study showed that specific receptors on the surface of leukocytes (PMN CD11b, monocyte CD14 and PMN CD16) are affected by the burn. Expression of PMN CD11b and CD16 are related to burn size. Burn-induced effects on the expression of PMN receptors, such as PMN CD11b and CD16, may contribute to burn-induced infection susceptibility.