bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intermittent Enteral Nutrition—A Comparative Study Examining the Effect on Gastric pH and Microbial Colonization Rates
Authors: Gowardman J. , Sleigh J. , Barnes N. , Smith A. , Havill J. 
Published: January 2019

In a prospective randomized study we aimed to examine the effect on gastric pH and microbial colonization of enteral nutrition (EN) delivered both by intermittent and continual infusion. Forty-three mechanically ventilated patients were randomized to receive EN by one of three methods, intermittent or continual gastric or continual jejunal. We sampled gastric aspirate for pH and culture in all patients at 0600 hours and pH in gastric intermittent feeders at 2200 hours daily. Patients were studied for 12 days or until extubated. Data was obtained on 41 patients, of whom 73% had a diagnosis of trauma. Median APACHE II score was 17 and ventilation time 11 days. Twelve patients received gastric continuous, 15 gastric intermittent and 14 jejunal nutrition. No significant difference was observed between the three groups with regard to median 0600 pH (P=0.16). This was lowest in the jejunal group (3.2) followed by the gastric intermittent group (4.0) and then gastric continuous group (5.0). With overnight cessation of EN in the gastric intermittent group, the median pH fell from 5.2 at 2200 to 4.0 at 0600 (P=0.01) with no effect on gastric colonization. The probability of gastric colonization over time however was significantly lower in the jejunal group compared with the two gastric groups (Log rank test, P=0.02). These results demonstrate that in a patient population consisting predominantly of trauma, overnight cessation of EN made no overall difference to 0600 gastric pH or colonization rates. The preservation of pH and lowered colonization in those given jejunal feeding may have implications in the pathogenesis of ventilator-associated infection and may warrant further study using larger patient numbers.
The Effects of a One Unit Blood Donation on Auto-haemodilution and Coagulation
Authors: Ruttmann T. G. , Roche A. M. , Gasson J. , James M. F. M. 
Published: January 2019

The effect of haemodilution on coagulation has been extensively investigated. We investigated auto-haemodilution following a 10% blood loss (480 ml) and its effect on coagulation. Ten healthy, unstarved volunteers were enrolled. One unit of blood was taken from each volunteer. Concurrently blood was taken from the opposite arm prior to and immediately after the blood donation, and at 1, 2, 4 and 6 hours. It was tested for thrombelastography, haematocrit and endorphins. There was a significant decrease in r-time from the control sample to the sample taken immediately post blood donation. This value returned to baseline at 1 hour post donation and did not change again. There were no other significant changes in thromboelastographic parameters. Fractional plasma noradrenaline changes were significantly raised at 1 hour post donation (P=0.048), returning to baseline by 2 hours post donation. The haematocrit showed a rapid (~4%) fall during donation followed by a slow, but progressive decrease over six hours, falling by a mean of 8.3% from pre-donation values. A state of relative hypercoagulability is found immediately after a rapid 10% loss in circulating blood volume. This may be related to the rapid immediate haemodilution. It is unlikely that the sympathetic response to blood loss plays a role. However, after the initial drop, slow restoration of circulating blood volume by autodilution takes six to eight hours, and is not associated with enhanced coagulation. Of interest is that a 10% blood loss in a healthy person does not require volume replacement.
An Easy Method of Mentally Estimating the Metabolic Component of Acid/base Balance Using the Fencl-Stewart Approach
Authors: Boyle M. , Lawrence J. 
Published: January 2019

The Stewart approach defines acid/base abnormalities as resulting from changes in PCO 2, strong ion difference (SID), and weak acids (mainly albumin) but needs a computer for calculation. The base excess (BE) is a measure of the net effect of changes in SID and weak acids, therefore, metabolic acid/base balance can be described as BE effects of their change from normal. We compared our mental estimation of BE effects with the more complex calculation. Acid/base abnormalities were identified in 44 critically ill patients. The BE effects of change in strong ions, change in albumin, and the BE-gap (“other species” or unmeasured anion effect) were calculated using standard equations. An estimate of the BE effects was determined. The difference between SID (using [Na + ]+[K+ ]-([Cl]+lactate)) and normal SID (42 mEq/l) estimated the effect of a change in SID. The effect of a change of albumin from normal was estimated as 0.252 (normal albumin-measured albumin). The predicted BE was defined as estimated change in SID plus albumin effect. The estimated BE-gap (BE-gap est ) was actual BE minus predicted BE. The Bland-Altman method was used to test agreement. Calculations were made on 46 data sets from 44 individuals. The bias (limits of agreement) for calculated and estimated strong ion effects, calculated and estimated albumin effect, and calculated and estimated BE-gap were -1.26 (-3.14 to 0.66) mEq/l, 0.5 (-0.05 to 1.05) mEq/l, and 0.76 (-1.27 to 2.79) mEq/l respectively. However the bias (limits of agreement) for BE-gap and BE-gap est and strong ion gap were poor, being 1.1 (-4 to 14) mEq/l and 0.4 (-9.2 to 10) mEq/l respectively. The BE-gap and BE-gap est are unsuitable to quantify gap ions. However, our easy-to-perform estimation has a clinically acceptable bias compared to calculated BE effects and is a simple method for identifying the components of acid/base abnormalities.
Implementing Intensive Insulin Therapy: Development and Audit of the Bath Insulin Protocol
Authors: Laver S. , Preston S. , Turner D. , McKinstry C. , Padkin A. 
Published: January 2019

Intensive insulin therapy to control blood glucose has been found to reduce mortality among critically ill patients in a surgical intensive care unit, though a simple prescriptive insulin infusion protocol to achieve this has not been published previously. This study documents the development and routine use of a simple prescriptive intravenous insulin infusion protocol for critically ill patients and compares the results with previous practice. During development the protocol was optimized and practical issues of implementation addressed. The optimized protocol was then used for all ICU admissions, and a prospectively defined retrospective chart audit performed for the first month of use. Results were compared with a similar time period the previous year. In September 2002, 27 admissions were started on the protocol. Blood glucose for the time on the protocol had a median value of 6.2 (IQR 5.9-7.1) mmol/l compared with 9.2 (IQR 8.1-10.2) mmol/l for those on insulin in 2001. Blood glucose for the whole ICU stay for those on the protocol in 2002 had a median value of 6.6 (IQR 6.0-7.4) mmol/l compared with 8.6 (IQR 8.0-9.4) mmol/l in 2001. Blood glucose for all ICU patients in 2002 had a median value of 6.5 (IQR 6.0-7.3) mmol/l compared with 7.2 (IQR 6.3-8.3) mmol/l in 2001. Three blood glucose recordings were less than 2.2 mmol/l in September 2002. This study provides initial effectiveness and safety data for the Bath Insulin Protocol. Further audits in a larger patient population are now needed.
Propofol Infusion Syndrome— Report of an Adult Fatality
Authors: Ernest D. , French C. 
Published: January 2019

This report describes a fatal case of the propofol infusion syndrome in an adult patient being sedated for a closed head injury using high doses of propofol. The features of circulatory collapse, metabolic acidosis, mild rhabdomyolysis and renal impairment are consistent with the syndrome and not readily attributable to alternative aetiologies. Potential mechanisms for the syndrome may relate to antagonism of beta-receptors, impaired myocardial oxygen utilization and a specific disruption to fatty-acid oxidation. This is the first published Australian case of the propofol infusion syndrome in an adult and should serve as an additional case report to the existing literature highlighting this potentially fatal syndrome in adults.
Is the Degree of Sensitivity to Nondepolarizing Muscle Relaxants Related to Requirements for Postoperative Ventilation in Patients with Myasthenia Gravis?
Authors: Kadoi Y. , Hinohara H. , Kunimoto F. , Niijima A. , Saito S. , Goto F. 
Published: January 2019

The purpose of this study was to examine whether the degree of sensitivity to nondepolarizing muscle relaxants is related to the requirement for postoperative ventilatory support in patients with myasthenia gravis. Thirty-six patients with myasthenia gravis undergoing trans-sternal thymectomy were monitored by electromyography in order to assess the neuromuscular response to vecuronium. After calibration to 100% of baseline electromyographic response values using an EMG monitor, incremental doses of 5, 10 and 20 μg/kg of vecuronium were administrated to produce 95% neuromuscular blockade and to obtain a cumulative dose-response curve for each patient. A univariable logistic regression with odds ratio was used to examine the predictive variables of prolonged postoperative ventilation. Depending on their postoperative ventilatory needs, patients were divided into an early extubation group and a prolonged ventilatory group. There were no significant differences between the two groups in terms of vecuronium ED95 (prolonged ventilation group: 23.2±18 μg/kg; early extubation group: 23.2±18 μg/kg, P=0.129) and vecuronium requirement to maintain less than 25% neuromuscular blockade (prolonged ventilation group: 2.4±1.7 mg/kg; early extubation group: 3.8±4.5 mg/kg, P=0.249). There were, however, significant differences in the incidence of a history of previous respiratory crises and the presence of bulbar palsy between the early extubation and prolonged ventilation groups. History of previous respiratory crisis (odds ratio (OR), 3.5; 95% confidence interval (CI), 1.0-13; P=0.03) and presence of bulbar palsy (OR, 3.7; 95%CI, 0.9-15; P=0.049) were associated with the need for prolonged postoperative ventilation. However, we failed to demonstrate that the degree of sensitivity to nondepolarizing muscle relaxants was related to an increased requirement for postoperative ventilation in patients with myasthenia gravis.
Crystalloid Preload versus Rapid Crystalloid Administration after Induction of Spinal Anaesthesia (Coload) for Elective Caesarean Section
Authors: Dyer R. A. , Farina Z. , Joubert I. A. , Du Toit P. , Meyer M. , Torr G. , Wells K. , James M. F. M. 
Published: January 2019

Current methods of crystalloid preload administration prior to spinal anaesthesia for elective caesarean section are relatively ineffective in preventing hypotension. This study examined the relevance of the timing of the fluid administered. Fifty women were randomly allocated to receive either 20 ml.kg–1 of crystalloid solution during 20 minutes prior to induction of spinal anaesthesia (preload), or an equivalent volume by rapid infusion immediately after induction (coload). Significantly more patients in the coload group did not require vasopressor therapy pre-delivery (P=0.047). The coload group required a lower median dose (P=0.03) and a lower median number (P=0.04) of ephedrine doses for the treatment of maternal hypotension pre-delivery. There was no between-group difference in either the total cumulative dose, or in the total number of doses of ephedrine. Neonatal outcomes among the two groups were similar. Rapid crystalloid administration after, rather than over 20 minutes before the induction of spinal anaesthesia for elective caesarean section, may be advantageous in terms of managing maternal blood pressure prior to delivery.
How Severe Acute Respiratory Syndrome (SARS) Affected the Department of Anaesthesia at Singapore General Hospital
Authors: Tan T. K. 
Published: January 2019

The effects of the outbreak of severe acute respiratory syndrome (SARS) on the Singapore General Hospital's Department of Anaesthesia are described. Urgent measures to protect staff and patients were implemented. Clear direction in administration issues and clinical pathways with good logistic support were essential. Anaesthetists were at risk and anaesthetic practice had to change in view of strict infection control provisions. Contingency planning for future infectious diseases outbreaks is required. Lessons can be learnt by hospitals yet to be visited by this virulent infection.
Barriers to Effective Perioperative Communication in Indigenous Australians: An Audit of Progress since 1996
Authors: Cheng W. Y. C. , Blum P. , Spain B. 
Published: January 2019

This prospective study was designed to elucidate barriers limiting effective perioperative communication between indigenous Australians and anaesthetists, and to identify strategies for improving communication. A questionnaire was used to collect data on 1040 consecutive patients undergoing anaesthesia at Royal Darwin Hospital between February and March 2003. 27.1% of these patients described themselves as Aboriginal. Aboriginal patients were more likely to undergo emergency surgery and were more likely to be classified as ASA 3, 4 or 5 than non-indigenous patients. Communication difficulties were identified in 28.7% of all Aboriginal patients, which was 31 times higher than those in non-Aboriginal patients. The most common reason identified for this was difficulty in speaking English. Only 17.7% of Aboriginal patients presenting to the operating theatre spoke English as their first language. Unfortunately, the anaesthetic team utilized the Aboriginal interpreter service in only a minority of cases. Communication difficulty in indigenous Australians is pervasive and often goes unrecognized. The results suggest that heath care providers may need staff training in cross-cultural communication and that protocols need to be developed within the health care system so that interpreters are called upon automatically early in the admission process.
The Effects on Arterial Haemoglobin Oxygen Saturation and on Shunt of Increasing Cardiac Output with Dopamine or Dobutamine during One-lung Ventilation
Authors: Russell W. J. , James M. F. 
Published: January 2019

Theoretically, if the cardiac output were increased in the presence of a given intrapulmonary shunt, the arterial saturation should improve as the venous oxygen extraction per ml of blood decreases if the total oxygen consumption remains constant. Previous work demonstrated that this was not achieved with adrenaline or isoprenaline as increased shunting negated any benefit from improved cardiac output and mixed venous oxygen content. However, pharmacological stimulation of cardiac output and venous oxygen without any increase in shunt should achieve the goal of improved arterial oxygenation. To test this hypothesis, seven pigs were subjected to one-lung ventilation and infused on separate occasions, with dopamine and with dobutamine in random order to increase the cardiac output. The mixed venous oxygen content, shunt fraction, oxygen consumption and arterial oxygen saturation were measured. With both dopamine and dobutamine there was a consistent rise in venous oxygen content. However, with dopamine, the mean shunt rose from 28% to 42% and with dobutamine, the mean shunt rose from 45% to 59% (both changes P<0.01). With dopamine, the mean arterial oxygen saturation fell by 4.7%, and with dobutamine by 2.9%, but neither fall was statistically significant. It is concluded that any benefit to arterial saturation which might occur from a dopamine- or dobutamine-induced increase in mixed venous oxygen content during one-lung ventilation is offset by increased shunting. During one-lung anaesthesia, there would appear to be no benefit to arterial saturation in increasing cardiac output with an infusion of either dopamine or dobutamine.
Night-shift Discharge from Intensive Care Unit Increases the Mortality-risk of ICU Survivors
Authors: Duke G. J. , Green J. V. , Briedis J. H. 
Published: January 2019

Intensive Care (ICU) survivors discharged from ICU to the general ward at night have a higher mortality1,2. We sought to clarify which factors, including night-shift discharge, influence outcome following ICU discharge in a metropolitan hospital, using a cohort study of critically-ill patients between 1/1/1999-30/4/2003. Patients were excluded from analysis if they (a) died in ICU, (b) were transferred to another hospital, (c) had an ICU length of stay <8 hours, or (d) age <16 years. Logistic regression was used to derive a predictive model based on the following variables: patient demographics, severity of illness following ICU admission (APACHE II mortality-risk, pm), final diagnosis, discharge timing including premature or delayed (>4 hours) ICU discharge, and “limitation of medical treatment” orders. The outcome measures were patient status at hospital discharge and ICU readmission rate. Of the 1870 ICU survivors, 92 (4.9%) died after discharge from ICU. Patients discharged to the ward during the night-shift (2200-0730 hours) had a higher APACHE II score and crude mortality. The difference in APACHE II pm did not reach statistical significance. No significant calendar or seasonal pattern was identified. Logistic regression identified night-shift discharge (RR=1.7; 95% CI 1.03-2.9; P=0.03), limited medical treatment order (RR=5.1; 95% CI 2.2-12) and admission APACHE II pm (RR=3.3; 95% CI 1.3-7.6) as independent predictors of patient outcome following ICU transfer to the ward. Conclusion: At the time of ICU discharge to the ward three factors are predictive of hospital outcome: timing of ICU discharge, limited medical treatment orders and initial illness severity.
Blood Usage in an Australian Intensive Care Unit: Have We Met Best Practice Goals?
Authors: Farrar D. , Robertson M. S. , Hogan C. J. , Roy S. , Boyce C. A. , Howe B. D. , Presneill J. J. , Cade J. F. 
Published: January 2019

The transfusion of blood products, especially red cell concentrates, in critically ill patients is controversial and benefits of red cell concentrate transfusion in these patients have not been clearly demonstrated. We performed a prospective observational study to compare best evidence to actual practice of red cell concentrate and other blood product administration in an intensive care unit (ICU) in a university-associated tertiary hospital. All primary admissions during a 28-day period were included in the study and data collected included transfusion of red cells and blood products, patient demographics and ICU and hospital outcome. One hundred and seventy-five admissions were studied; 44% followed cardiac surgery. Forty-one patients (23%) received red cell concentrates in ICU, with 120 units transfused in 61 separate episodes. Other blood product usage was minimal. One third (20/61) of red cell concentrate transfusion episodes were of a single unit. The mean (±SD) pre-transfusion haemoglobin was 7.9±1.1 g/dl. Despite transfusion, such patients left ICU with a lower haemoglobin concentration compared with untransfused ICU patients (9.5±1.0 versus 10.5±2.1 g/dl; P<0.001). Cardiac surgical patients received similar red cell transfusion to general ICU patients. Univariate analysis showed no significant difference in mortality between patients who did or did not receive red cell concentrate transfusion (P=0.17). However, red cell concentrate transfusion was associated with a reduced adjusted mortality both in ICU (OR 0.13, 95% CI 0.02-0.73) and in hospital at 28 days (OR 0.10, 95% CI 0.02-0.58). The low red cell concentrate and blood product usage in our ICU were consistent with restrictive transfusion practice and selective red cell concentrate transfusion was associated with reduced mortality.
Comparison of the Re-usable LMA Classic™ and Two Single-use Laryngeal Masks (LMA Unique™ and SoftSeal™) in Airway Management by Novice Personnel
Authors: Tan M. G. E. , Chin E. R. C. , Kong C. S. , Chan Y. H. , Ip-Yam P. C. 
Published: January 2019

In a single-blind randomized trial, three types of laryngeal masks: the reusable LMA Classic™, the single-use LMA Unique™ and SoftSeal™ were inserted by novice medical officers in anaesthesia. Five successive attempts were undertaken with each mask type. The order of the mask type insertion was randomly selected. Mean (SD) insertion times for LMA Classic™, LMA Unique™ and Soft Seal™ were 32.9 (12.3), 39.6 (23.4) and 49.4 (50.4) seconds respectively. Differences were only significant between LMA Classic™ and SoftSeal™ (P=0.012). There were no significant differences in first attempt success rates (LMA Classic™ 80%, LMA Unique™ 77% and SoftSeal™ 62%). The SoftSeal™ was most frequently associated with blood on the mask (32%) compared to the LMA Unique™(9%) and LMA Classic™ (6%). Sore throat was experienced in 14% of patients in the LMA Unique™ group versus 41% and 42% in the LMA Classic™ and SoftSeal™ groups respectively. Mean±SD oropharyngeal leak pressure was significantly higher in the SoftSeal™ (21±6 cmH2O) compared to the LMA Classic™ (17±7 cmH2O) and LMA Unique™ (16±6 cmH2O). Novice medical doctors can be taught to insert disposable laryngeal masks. The SoftSeal™ took longer to insert, which resulted in a higher incidence of blood on the mask, but success rates did not differ. The LMA Unique™ was associated with the lowest incidence of sore throat in the immediate postoperative period. A higher oropharyngeal leak pressure with the SoftSeal™ may indicate improved airway seal and protection against aspiration.
Severe Uncontrolled Pain in Buttock in a Patient on Naltrexone: A Diagnostic Challenge
Authors: Graham J. M. , Evans B. 
Published: January 2019

A 26-year-old woman with a history of intravenous drug use was admitted to hospital with worsening pain in the right buttock radiating to the lateral part of the thigh and to the calf with no suspicion of cauda equina compression. Eventually, a diagnosis of sacroiliitis was made and appropriate antibiotics were administered. Provision of analgesia for this patient was difficult. On admission her medications included naltrexone, venlafaxine and tramadol. Initially naltrexone was continued and analgesia provided by epidural local anaesthetic and clonidine, intravenous ketamine and oral agents. After several days, naltrexone was ceased and opioids were used in addition to the other analgesics. The epidural analgesia was only partially effective, perhaps because of inadequate blockade of the L4-S1 nerve roots, which carry sensation from the sacroiliac joint. Naltrexone is a long-acting opioid antagonist. If opioid analgesia is planned, it is necessary to cease naltrexone for 24 to 72 hours. In an emergency, if non-opioid techniques prove ineffective, short-acting opioids can be titrated to effect in a monitored environment.