bluuebunny/crossref_metadata_2025 huggingface dataset:
Rohrer's Constant, K2, as a Factor of Determining Inspiratory Resistance of Common Adult Endotracheal Tubes
Authors: Flevari A. G. , Maniatis N. , Kremiotis T. E. , Siempos I. , Betrosian A. P. , Roussos C. , Douzinas E. , Armaganidis A.
Published: January 2019

The aim of the study was to calculate the in vitro inspiratory resistance (RETT) of adult endotracheal tubes (ETT), via the end-inspiratory occlusion method, and to apply this method in vivo in order to estimate RETT value in real time. By plotting RETT over inspiratory flow (V) and calculating Rohrer's coefficients of linear and nonlinear resistance, K1 and K2 respectively, we determined the resistive behaviour of each ETT.

Peak and plateau pressures were recorded at both proximal and distal sites of the ETT after applying a three-second occlusion under constant flow. Distal pressure was obtained via an intraluminal catheter. RETT was calculated as (Ppeak – Pplateau)/(V;), at both sites. RETT value resulted from the difference Rproximal - Rdistal. Graph RETT over (V;) was plotted and Rohrer's constants were calculated by the method of least squares.

For ETTs with inner diameter 9.0, 8.5, 8.0, 7.5, 7.0 and 6.5 mm, K2 was 2.42, 3.05, 4.65, 6.01, 9.17 and 12.80 cmH2O/l/s, respectively. The intraluminal catheter increased RETT No.7.0 by an average of 49%. Finally, ten patients with partially obstructed ETTs were tested and K2 in vivo constants found to be higher than their corresponding in vitro values (P value 0.00012).

Therefore, knowing the performing size of an ETT may help the clinicians identify ETT obstruction and deal with weaning problems.
Retrospective Audit of Blood Transfusion and Comparison with Haemoglobin Concentration in Patients Undergoing Elective Primary and Revision Lower Limb Arthroplasty
Authors: Evans S. , O'Loughlin E. , Bruce J.
Published: January 2019

We retrospectively audited the incidence of blood transfusion and related this to preoperative haemoglobin levels in 181 patients undergoing lower limb arthroplasty over a six-month period. This included 102 primary total knee replacements, 52 primary total hip replacements, 11 revision total knee replacements and 16 revision total hip replacements.

The overall incidence of transfusion was 16.0%. The incidence in primary arthroplasty was 11% (9.8% for total knee replacements and 13.5% for total hip replacements), and in revision surgery was 44.4% (27.3% for total knee replacements and 56.3% for total hip replacements).

Combining data for primary total knee replacements and primary total hip replacements, a preoperative haemoglobin threshold of 120 g/l divided patients into high and low risk groups for transfusion. Below or equal to this threshold the incidence of transfusion was 47.7%; above this threshold the incidence was 7.2%.

We suggest that patients having primary lower limb arthroplasty with a preoperative haemoglobin of 120 g/l or less should undergo investigation of their anaemia and optimisation of erythropoeisis.
Concurrent Intracardiac Metastasis in a Patient with Intestinal Perforation
Authors: Lee C. T. , Farrell S. , Silbert B. S.
Published: January 2019

The administration of anaesthesia to subjects with intracardiac lesions poses the potential for cardiac complications.

Cardiac metastases should be identified in susceptible cases and transthoracic echocardiography performed to elucidate the nature of the cardiac lesions. We describe a case of an intracardiac metastasis in a 65-year-old subject with a small bowel tumour leading to intestinal perforation and presenting for surgical treatment. Oncological assessment of the situation, in conjunction with the anaesthetic risks, led to abandonment of surgery and palliative treatment.
Comparison of the Effect-Site Concentrations of Remifentanil for Streamlined Liner of the Pharynx Airway (SLIPA™) versus Laryngeal Mask Airway Softseal™ insertion during Target-Controlled Infusion of Propofol
Authors: Kim S. H. , Choi E. M. , Chang C. H. , Kim H. K. , Chung M. H. , Choi Y. R.
Published: January 2019

This study was designed to determine the optimal dose of remifentanil required for the successful insertion of Streamlined Liner of the Pharynx Airway (SLIPA™) and to compare it to that required for laryngeal mask airway (LMA) insertion in patients receiving a propofol infusion at a standard effect-site concentration.

Fifty-eight patients scheduled to undergo general anaesthesia were randomly assigned to either the SLIPA (n=29) or LMA (n=29) group. All patients were premedicated with midazolam 0.05 mg.kg-1 and glycopyrrolate 0.004 mg.kg-1 intramuscularly. After the administration of lignocaine 1 mg.kg-1 intravenously, a propofol infusion was started at an effect-site concentration of 3.5 μg.ml-1 with a remifentanil infusion without a neuromuscular blocking agent. The remifentanil dose was determined by the modified up-and-down method starting in each group at 4 ng.ml-1. Six minutes after induction, the airway device was inserted. Airway device insertion was classified as ‘success’ or ‘failure’ based on patient response.

From the isotonic regression analysis and bootstrap distribution, the EC50 of remifentanil for SLIPA and LMA were 0.93 ng.ml-1 (95% confidence interval [CI] 0.81 to 1.50 ng.ml-1) and 1.36 ng.ml-1 (95% CI 1.19 to 2.06 ng.ml-1) respectively, and the EC95 for SLIPA and LMA insertions were 1.90 ng.ml-1 (95% CI 1.39 to 1.95) and 2.43 ng.ml-1 (95% CI 1.80 to 2.46 ng.ml-1) respectively. Using the 83% CIs from the bootstrap distribution, EC50 for SLIPA was significantly less than that of LMA (0.83 to 1.23 vs 1.26 to 2.00, respectively) (P <0.05).

These findings suggest that the insertion of SLIPA needs about a 32% lower depth of anaesthesia than LMA insertion.
Effectiveness of the Streamlined Liner of the Pharynx Airway (SLIPA™) in Allowing Positive Pressure Ventilation during Gynaecological Laparoscopic Surgery
Authors: Hong S. J. , Ko K. M. , Park J. H. , Kim I. S. , Hwang S. M. , Shin K. M. , Yoon Y. J. , Kang S. S.
Published: January 2019

The aim of this study was to assess whether the Streamlined Liner of the Pharynx Airway (SLIPA™) performed as well as an endotracheal tube for positive pressure ventilation in gynaecological laparoscopic surgery in the Trendelenburg position. Forty patients (American Society of Anesthesiologists physical status I to III) were randomly divided into two groups: SLIPA (n=20) or endotracheal tube group (n=20). Lung mechanics and severity of postoperative sore throat were assessed in both groups. In the SLIPA group, the oropharyngeal leak pressure was also measured.

There were no significant differences between groups in the lung mechanics. In the SLIPA group, oropharyngeal leak pressure and peak inspiratory pressure increased significantly after gas insufflation compared to 10 minutes after patient positioning in the lithotomy position (P <0.05). The difference between oropharyngeal leak pressure and peak inspiratory pressure (approximately 10 cmH2O throughout the procedure) remained suitable for airway maintenance. The incidence of sore throat was similar in both groups but the severity was less in the SLIPA group 24 hours after surgery (P <0.05). There were no other complications such as regurgitation noted in either group. In the study population, the SLIPA performed as well as an endotracheal tube in allowing positive pressure ventilation without gas leak during gynaecological laparoscopy. The way in which the SLIPA increases its resistance to gas leak as the inspiratory pressure rises may account for this.
The Efficacy of Ultrasound-Guided Transversus Abdominis Plane Block in Patients Undergoing Hysterectomy
Authors: Atim A. , Bilgin F. , Kilickaya O. , Purtuloglu T. , Alanbay I. , Orhan M. E. , Kurt E.
Published: January 2019

The study objective of this prospective, double-blind randomised controlled study was to evaluate the efficacy of ultrasound guided transversus abdominis plane (TAP) block and bupivacaine infiltration of the skin and subcutaneous tissue of the wound in patients undergoing hysterectomy. Patients were randomly allocated to three groups: a control group (n=18) and TAP block group (n=18) received bilateral TAP blocks with saline and bupivacaine respectively, and an infiltration group (n=19) received skin and subcutaneous wound tissue infiltration with bupivacaine at the end of surgery. After surgery patients received patient-controlled intravenous tramadol and were assessed for pain and tramadol consumption at 1, 2, 4, 6 and 24 hours.

Both the TAP and infiltration groups had lower movement and rest pain scores than the control group, with lower scores in the TAP group than the infiltration group at 6 and 24 hours. Total tramadol consumption was significantly lower in the TAP group than in the other groups at all time points. We concluded that ultrasound-guided TAP block reduced rest and movement pain after total abdominal hysterectomy and was more effective than superficial wound infiltration for postoperative pain management.
Ondansetron does not Modify Emergence Agitation in Children
Authors: Hoşten T. , Solak M. , Elemen L. , Ozgun M. , Toker K.
Published: January 2019

In this prospective, placebo-controlled study, we evaluated the effect of prophylactic ondansetron therapy on emergence agitation of children who underwent minor surgery below the umbilicus. Seventy children aged one to six years and American Society of Anesthesiologists physical status I were studied. Children were premedicated with midazolam rectally and were randomly assigned to receive either ondansetron (Group O) or placebo (Group P) in combination with caudal anaesthesia. Children in Group O received intravenous ondansetron (0.1 mg/kg for children weighing <40 kg, 4 mg for children weighing >40 kg) and Group P (n=35) received normal saline 2 ml following anaesthesia induction with sevoflurane. Airway management was provided with LMA-Proseal without muscle relaxation and anaesthesia maintenance was provided with a 60:40 N2O:O2 mixture and sevoflurane. Emergence agitation was evaluated with a ten point scale and pain level was assessed every 10 minutes for the first 30 minutes after admission to the recovery room.

There were no significant differences between the placebo and ondansetron groups with respect to demographic, anaesthetic and surgical details. Incidences of emergence agitation in ondansetron and placebo groups were similar (32.4% and 30.3% at 10 minutes respectively). Mean modified Children's Hospital of Eastern Ontario pain scale scores and mean ten-point scale scores and emergence agitation incidences decreased similarly after 10 minutes in both groups. Ready time for discharge was similar between the groups. Agitated patients had significantly increased ready time for discharge compared to non-agitated patients (P=0.001).

Prophylactic intravenous ondansetron administration does not reduce emergence agitation comparing to placebo after sevoflurane anaesthesia.
Comparison of Predicted and Perceived Pain from Epidural and Spinal Puncture in Patients Undergoing Elective Caesarean Section
Authors: Yano T. , Iwasaki T. , Naruo H. , Tsuneyoshi I.
Published: January 2019

The intensity of pain expected by patients before an epidural and/or a spinal puncture is uncertain. The main purpose of this study was to identify and compare the intensity of pain predicted and perceived by patients having an epidural and a spinal procedure. After screening for relevant exclusion criteria, 50 women who were undergoing elective caesarean section under combined spinal-epidural anaesthesia (double-segment technique) were enrolled in the study. Infiltration anaesthesia prior to needle insertion was performed for the epidural but not the spinal puncture. Pain assessments, using a 100 mm visual analogue pain scale, were made before (predicted pain) and after (perceived pain) the epidural and the spinal puncture. Predicted pain for epidural and spinal insertion (epidural 60.6±20.5 mm, spinal: 55.1±24 mm) was significantly higher than the pain perceived (epidural 36.3±20 mm, spinal 46.1±23.2 mm) (epidural P <0.001, spinal P=0.031). Patients who were scheduled for an elective caesarean section under combined spinal-epidural anaesthesia predicted 1.2- to 1.7-fold stronger pain intensity than they perceived during the procedure. Patients should be informed that a regional anaesthetic, especially epidural, procedure is often less painful than the patient's expectation.
Remifentanil Patient-Controlled Analgesia for Labour: A Complete Audit Cycle
Authors: Buehner U. , Broadbent J. R. , Chesterfield B.
Published: January 2019

Remifentanil patient-controlled analgesia (PCA) was introduced to a small maternity unit where an extensive epidural service was difficult to provide. This was a new service and the New Zealand College of Midwives had serious doubts about the efficacy and safety of remifentanil, so auditing its use was important.

In a two-stage audit, clinical notes of 244 consecutive remifentanil users were studied between January 2008 and November 2009. We developed a questionnaire to assess the parturients’ satisfaction with remifentanil PCA and designed a proforma to evaluate it against four standards of best practice.

During the two audit periods, timely commencement of PCA was achieved in 65% and 82% of cases, respectively. A 70% compliance rate with monitoring standards fell to 10% after the withdrawal of supervision by an acute pain team, but improved to 91% following implementation of regular midwifery training sessions and a redesigned partogram and prescription flowchart. Ninety-four percent of women rated remifentanil PCA as excellent, very good or good. Maternal side-effects were nausea, pruritus and drowsiness. A comparison of Apgar scores of consecutive neonates born by normal vaginal delivery to women receiving no analgesia, with those born to women using remifentanil PCA, demonstrated no difference.

As a result of our audit, remifentanil PCA is now viewed by our midwives as an effective and safe method when accompanied by 1:1 care and appropriate monitoring. With our input other maternity units have introduced it, especially where epidural service provision is limited, and for patients in whom epidural analgesia is contraindicated.
Intraoperative Thrombolysis in a Patient with Cardiopulmonary Arrest Undergoing Caesarean Delivery
Authors: Wenk M. , PÖPping D. M. , Hillyard S. , Albers H. , MÖLlmann M.
Published: January 2019

Thromboembolic events during pregnancy remain a major cause of morbidity and mortality with possible catastrophic sequelae for the patient. The decision whether to use high-risk therapeutic thrombolytics during pregnancy or perinatally is complicated and many considerations pertain. We report on the thrombolytic management of a 34-year-old woman who had an asystolic cardiac arrest secondary to massive pulmonary embolism while undergoing emergency caesarean delivery. The patient was thrombolysed during successful cardiopulmonary resuscitation. Return of spontaneous circulation was accompanied by massive uterine bleeding. Instead of performing a postpartum hysterectomy, the uterus was preserved through continuous manual pressure and packing for four hours by the obstetric team until haemostasis was achieved. The patient survived and was later discharged without any major neurological deficit.
Patient-Controlled Analgesia Syringe Pumps
Authors: Westhorpe R. N. , Ball C.
Published: January 2019

The idea of administering repeated small doses of a drug intravenously is not new, but it took many years for the method to become part of the routine clinical management of pain.

The traditional practice of administering an opioid in a predetermined dose by intramuscular or subcutaneous injection, and at predetermined minimal intervals, led to usually inadequate and intermittent pain relief. The dosage of opioid was often determined so as to be conservative and ‘safe’, and administration depended on patient request and availability of nursing staff.
The Transition from Acute to Chronic Post Surgical Pain
Authors: Shipton E. A.
Published: January 2019

All chronic pain was once acute, but not all acute pain becomes chronic. The transition of acute postoperative pain to chronic post surgical pain is a complex and poorly understood developmental process. The manuscript describes the various factors associated with the transition from acute to chronic pain. The preoperative, intraoperative and postoperative surgical, psychosocial, socio-environmental and patient-related factors and the mechanisms involved are discussed and preventive (or limitation) strategies are suggested. In future, the increasing understanding of genetic factors and the transitional mechanisms involved may reveal important clues to predict which patients will go on to develop chronic pain. This may assist the development of appropriate interventions affecting not only the individual concerned, but also ultimately the community at large.
C-Reactive Protein as a Predictor of Mortality in Critically Ill Patients: A Meta-Analysis and Systematic Review
Authors: Zhang Z. , Ni H.
Published: January 2019

C-reactive protein is a marker of inflammatory response and has been widely investigated in cardiovascular and infectious diseases, especially to monitor therapeutic success. However, its role as a predictor of clinical outcome in critically ill patients remains uncertain and controversial. The objective of this study was to investigate the predictive value of C-reactive protein in critically ill patients.

The databases of PubMed, the Cochrane clinical trial database and EMBASE (from inception to August 2010) were searched. Prospective non-randomised clinical studies comparing C-reactive protein concentrations between survivors and non-survivors were included. Pooled mean difference in C-reactive protein concentrations between survivors and non-survivors was calculated. Heterogeneity was analysed by I2. Sensitivity and subgroup analyses were conducted to explore the heterogeneity.

Fourteen studies containing a total of 1969 patients were finally included in our analysis. The weighted mean difference in the C-reactive protein levels between survivors and non-survivors was 9.15 mg/l (95% confidence interval -6.50 to 24.81). The heterogeneity was large with I2=92%. Subsequent investigation of the heterogeneity with sensitivity analyses yielded no significant differences. The subgroup analysis showed that the weighted mean difference in early (within 48 hours) C-reactive protein levels between survivors and non-survivors was not significantly different, in contrast to the late (beyond 48 hours) C-reactive protein level. This was significantly greater in non-survivors with a weighted mean difference of 63.80 mg/l (95% confidence interval 35.67 to 91.93).

Our systematic review shows that while the early C-reactive protein concentration is not a good predictor of survival in critically ill patients, the late C-reactive protein concentration may help to identify patients who are at risk of death.
Cardiac Output and Propofol Concentrations in Prone Surgical Patients
Authors: Leslie K. , Wu C. Y.-X. , Bjorksten A. R. , Williams D. L. , Ludbrook G. , Williamson E.
Published: January 2019

The aim of this study was to compare cardiac output and plasma propofol concentrations in the supine and prone positions in healthy adult patients presenting for lumbar spine surgery. Patients received propofol and remifentanil via effect-site steered target-controlled infusions. Cardiac output and plasma propofol concentration were compared during 20 minutes in the supine position and 20 minutes after positioning on a Wilson frame. Cardiac output did not change significantly over 20 minutes in either position (P=0.37) and was similar at 20 minutes in the supine (6.1 [1.6] l/minute) and prone positions (6.1 [1.9] l/minute) (P=0.87). Propofol concentrations were similar in the supine and prone positions at 20 minutes (2.55 [0.89] and 2.53 [0.90] μg/ml; P=0.93). We conclude that prone positioning on the Wilson frame does not affect cardiac output or plasma propofol concentration.
Cerebrospinal Fluid Cytology in Patients Undergoing Combined Spinal Epidural versus Spinal Anaesthesia without an Introducer
Authors: Sharma B. , Gupta S. , Jain N. , Handoo A. , Sood J.
Published: January 2019

The problem of tissue coring exists despite the availability of smaller gauge spinal needles with special tip designs. The aim of the study was to test the hypotheses that a) subarachnoid block given as a part of a combined spinal epidural intervention by needle-through-needle technique introduces a lesser number of epithelial cells into the subarachnoid space compared to isolated subarachnoid block, and b) after lumbar puncture, the initial few drops of cerebrospinal fluid from the spinal needle will have a higher number of epithelial cells than the subsequent sample.

One hundred and seven patients of American Society of Anesthesiologists physical status I to III undergoing infra-umbilical surgery were enrolled. Seven patients were excluded from the study and the rest divided into two groups to receive either combined spinal epidural anaesthesia (group A) or isolated subarachnoid anaesthesia, unaided by an introducer (group B). The two groups were compared for the presence of epithelial cells in cerebrospinal fluid. The initial four to six drops of cerebrospinal fluid (sample 1) were collected, the next four to six drops discarded and the following four to six drops (sample 2) collected.

The incidence of coring was 96% in group A and 88% in group B (P=0.142). The median (interquartile range) number of cells in group A, for samples 1 and 2 was 6 (3 to 12.5) and 6 (3 to 10); and in group B, 3.5 (1 to 10) and 4 (1 to 8) respectively.

Significant tissue coring was observed with both techniques. Discarding eight to 12 drops of cerebrospinal fluid did not help in reducing the epithelial cell load.
Optimum Bolus dose of Propofol for Tracheal Intubation during Sevoflurane Induction without Neuromuscular Blockade in Children
Authors: Kim S.-H. , Hong J.-Y. , Suk E. H. , Jeong S. M. , Park P. H.
Published: January 2019

The purpose of this study was to determine the optimum bolus dose of propofol required to provide excellent conditions for tracheal intubation following inhalational induction of anaesthesia using 5% sevoflurane without neuromuscular blockade. Twenty-eight children, aged three to seven years, requiring anaesthesia for short duration surgery were recruited. Two minutes after beginning the inhalational induction with 5% sevoflurane and 60% nitrous oxide, a predetermined dose of propofol was injected over 10 seconds. Propofol dose was determined using the Dixon's up-and-down method, starting from 3 mg/kg (0.5 mg/kg as a step size). Laryngoscopy was performed 50 seconds after propofol injection. The optimum dose of propofol required for excellent intubating conditions was 1.39±0.37 mg/kg in 50% of children during inhalation induction using 5% sevoflurane and 60% nitrous oxide in the absence of neuromuscular blocking agents. From probit analysis, the 95% effective dose of propofol was 2.33 mg/kg (95% confidence interval 1.78 to 6.21 mg/kg).
Do We Understand the Impact of Altered Physiology, Consequent Interventions and Resultant Clinical Scenarios in the Intensive Care Unit? the Antibiotic Story
Authors: Lipman J. , Udy A. A. , Roberts J. A.
Published: January 2019

Early, appropriate antibacterial therapy is a key factor in effectively managing septic critically ill patients1. The prescriber must not only employ an agent of appropriate spectrum, but also in an adequate dose to achieve bacterial eradication at the site of infection. However, the relationship between drug administration and therapeutic success is complex in the critically ill, such that a patient's physiology heavily influences the way drugs distribute into tissue and are eliminated. This represents a significant challenge to the emergency or intensive care physician, and in this manner, personalising therapy, through a greater understanding of how a drug will behave in an individual patient, is likely to lead to improved outcomes.
Two-Dimensional Mapping to Assess Direction and Magnitude of Needle Tip Error in Ultrasound-Guided Regional Anaesthesia
Authors: Hebard S. , Hocking G. , Murray K.
Published: January 2019

We assessed whether echogenic needles reduce tip location error, by comparing three echogenic designs (Pajunk Sonoplex, Lifetech, B. Braun Stimuplex D+) with a non-echogenic control (Pajunk Uniplex), using a novel assessment technique in unembalmed human cadavers. Multiple images were taken of each needle at shallow (15 to 25°), moderate (35 to 45°) and steep (55 to 65°) insertion angles. Twenty anaesthetists with varied experience in ultrasound-guided nerve blocks identified needle tip position and stated their confidence level in estimates. Actual tip position was determined at the time of image generation but concealed from the anaesthetists. Two-dimensional mapping of ‘tip-error’ involved measurement of the distance and orientation of each clinician's estimate of tip position in relation to the actual tip position. There were no significant differences in confidence or overall needle visibility at shallow insertion angles. At steeper angles, the Sonoplex showed significantly higher confidence and visibility scores. The remaining echogenic designs did not show any significant differences from the non-echogenic control. Objective measurements of tip error followed the same pattern as the subjective data, although were not universally significant. Two-dimensional mapping showed that as needle visibility deteriorated, so precise tip location was lost but the needle shaft/insertion path remained well-identified. As visibility deteriorated further, accuracy in this axis was also lost. When inaccurate, clinicians generally assessed the needle tip to be more superficial and inserted less far than it actually was. This has important implications for the safety of ultrasound-guided regional anaesthesia. Effective echogenic needle technology has the potential to address these concerns.
A Triad Algorithm for Analysing Individual Ante- and Post-Mortem Findings to Improve the Quality of Intensive Care
Authors: Podbregar M. , Kralj E. , Čičak R. , Pavlinjek A.
Published: January 2019

Autopsy is an important source of data for education and quality control. The aim of this study was comparison of ante- to post-mortem findings to detect weak points of intensive care unit (ICU) care. Patients who died in our 14-bed university medical ICU care and underwent an autopsy examination over 20 months (September 2007 to May 2009) were included. Modified Goldman's criteria were used to categorise discrepancies between diagnoses and post-mortem findings. A triad algorithm was constructed to analyse individual ante- to post-mortem findings. One hundred and seventy post-mortem examinations were conducted (45.6% autopsy rate). Major diagnostic discrepancies were detected in 20 patients (11.8%); four class I (2.4%) and 16 class II (9.4%). Massive pulmonary embolism with cardiac arrest was the most common class I discrepancy (75%). Triad analysis of major class I discrepancies showed that all patients had a history of chronic disease; the majority (75%) had a short ICU length of stay. In 75% adequate tests were used to detect disorders. There were interpretation problems of bedside data in complex emergency clinical conditions, especially with less experienced ICU physicians. Inappropriate or incorrectly interpreted diagnostic procedures were performed in more than half of cases with class II discrepancies (9/16, 56%). Abdominal ultrasonography was misleading in 31% (5/16) cases with class II discrepancies. In conclusion, triad algorithm analysis revealed problematic interpretation of bedside diagnostics in emergency cases by inexperienced physicians in class I major discrepancies detected at autopsy. No correct test and wrong interpretation of abdominal ultrasonography were major causes of class II discrepancies.
Comparison of the Bonfils and Levitan Optical Stylets for Tracheal Intubation: A Clinical Study
Authors: Webb A. , Kolawole H. , Leong S. , Loughnan T. E. , Crofts T. , Bowden C.
Published: January 2019

The Bonfils and Levitan FPS™ scopes are rigid fibreoptic stylets that may assist routine or difficult intubation. This study compared the effectiveness of each in patients with predicted normal airways when used by specialist anaesthetists with no prior experience using optical stylets. Twelve anaesthetists and 324 elective surgical patients participated. Six anaesthetists were randomised to first intubate 20 patients with the Levitan scope (Phase 1) followed by a further seven patients with the Bonfils scope (Phase 2). The other six participating anaesthetists undertook their first 20 intubations with the Bonfils (Phase 1), followed by seven intubations with the Levitan (Phase 2). Outcomes recorded were success rate, total time to intubation, number of attempts, ease of intubation score and incidence of complications. Overall failure rates were similar for the two scopes with 5.6% of patients not intubated after three attempts. Median total times to intubation were similar for the Levitan (44 seconds) and Bonfils (36 seconds) (P=0.11). Participants using the Bonfils in Phase 1 had significantly higher chance of success on first attempt (73%) compared to Levitan users during Phase 1 (57%) (P=0.008). These differences were not significant in the second phase and ease of intubation scores were similar for both scopes (P=0.9). This study showed the two scopes were comparable but the high failure rate amongst novice users demonstrated the importance of familiarity and skill development prior to their introduction to a difficult airway cart.
Surgical Tension Pneumothorax during Laparoscopic Repair of Massive Hiatus Hernia: A Different Situation Requiring Different Management
Authors: Phillips S. , Falk G. L.
Published: January 2019

During laparoscopic repair of massive hiatus hernia, surgical dissection can breach the parietal pleura allowing insufflating carbon dioxide to rapidly expand the pleural space, causing a tension pneumothorax. This extrapulmonary pneumothorax involves no damage to the lung parenchyma. Its rapid resolution is aided by the high solubility of carbon dioxide and it will not refill once the procedure is completed. In this series of 50 massive hiatus hernia repairs the incidence of pneumothorax was 22% (11/50), with two of these being bilateral. Cardiovascular compromise occurred in 91% of those (10/11). The aetiology, pathophysiology and management of this intraoperative capnothorax differ significantly from that of a pneumothorax secondary to lung trauma or occurring during other types of laparoscopy. Understanding the relevant pleural anatomy and pathophysiology of this condition allowed conservative management in all cases and avoided the need for chest drains, open surgery or abandonment of the procedure.
Thrombotic Microangiopathy in Two Tiger Snake Envenomations
Authors: Casamento A. J. , Isbister G. K.
Published: January 2019

Thrombotic microangiopathies are a rare group of disorders with features such as microangiopathic haemolytic anaemia, thrombocytopenia and renal failure. Thrombotic microangiopathy has been previously reported in association with envenomation from a number of snake species. We present the first two reported cases of thrombotic microangiopathy caused by envenomation from the common tiger snake (Notechis scutatus). Both patients had classical features of thrombotic microangiopathy with microangiopathic haemolytic anaemia, thrombocytopenia and renal failure commencing in the first 48 hours after envenomation. The presentations and recovery were similar to case presentations of other snakebite envenomation associated thrombotic microangiopathies. Normal ADAMTS13 activity suggests that plasmapharesis may not be beneficial, although this needs further investigation.
Acute Dapsone Overdose: The Effects of Continuous Veno-Venous Haemofiltration on the Elimination of Dapsone
Authors: Masurkar V. A. , Edstein M. D. , Gorton C. J. , Anstey C. M.
Published: January 2019

A 15-year-old girl presented after intentional ingestion of dapsone (7.2 g) and small quantities of azathioprine, methotrexate and prednisolone. The resulting methaemoglobinaemia and lactic acidosis persisted despite treatment with methylene blue, multiple-dose activated charcoal and ascorbic acid. Continuous veno-venous haemofiltration for 75 hours was used to treat the dapsone overdose. The patient's serum dapsone concentrations were measured during and after continuous veno-venous haemofiltration. The rate of elimination of dapsone was over three times higher during, compared to after, continuous veno-venous haemofiltration. Continuous renal replacement therapy successfully reduced toxic dapsone concentrations in this patient with a good outcome.
Laptops and Smartphones in the Operating Theatre - How does our Knowledge of Vigilance, Multi-Tasking and Anaesthetist Performance Help us in our Approach to this New Distraction?
Authors: Jorm C. M. , O'Sullivan G.
Published: January 2019

There has been no research performed concerning the effects of the use of laptops and smartphones in the operating theatre on anaesthetist performance, yet these devices are now in frequent use. This article explores the implications of this phenomenon. The cognitive and environmental factors that support or detract from vigilance and multi-tasking are explored and core anaesthetic literature on the nature of anaesthetic work and operating theatre distractions is reviewed. Experienced anaesthetists are skilled at multi-tasking while maintaining situational awareness, but there are limits. Noise, interruptions and emotional arousal are detrimental to the cognitive performance of anaesthetists. While limited reading during periods of low task load may not reduce vigilance, computer use introduces text-based activities that are more interactive and potentially more distracting. All anaesthetists need to be mindful of the limits to the human attention span which requires observation and limiting distractions. Trainees have less experience and less ‘attentional’ safety margin, so should avoid adding additional distractions such as discretionary use of laptops or smartphones to their operating theatre work. We provide recommendations for future research on the specific advantages and disadvantages of pervasive computing in the operative theatre.
Benefits and Risks of Using Gelatin Solution as a Plasma Expander for Perioperative and Critically Ill Patients: A Meta-Analysis
Authors: Saw M. M. , Chandler B. , Ho K. M.
Published: January 2019

This meta-analysis aimed to evaluate the benefits and risks of gelatin solutions compared to other intravenous fluids for patients in perioperative and critical care settings. Of the 66 studies identified from MEDLINE and EMBASE databases, 30 randomised controlled trials involving 2709 patients met the inclusion criteria and were subject to meta-analysis. The risk of mortality (odds ratio 1.03, 95% confidence interval 0.80 to 1.32) and amount of blood loss (weighted-mean-difference 7.56 ml, 95% confidence interval 18.75 to 33.87) were not significantly different between patients who were treated with gelatin solutions and other types of intravenous fluids. When compared to starches, gelatin solutions were associated with a lower risk of acute renal failure (odds ratio 0.43, 95% confidence interval 0.20 to 0.92; P=0.03). When gelatin solutions were compared to isotonic albumin, patients who were treated with gelatin solutions required a small, but significantly greater amount of blood transfusion (weighted-mean-difference 180 ml, 95% confidence interval 8.1 to 353.6; P=0.04). These findings suggest that using gelatin solutions is associated with a lower risk of acute renal failure compared to older starches. Using gelatin as a plasma expander appears to have no significant advantages over crystalloids or isotonic albumin on mortality and may have a slightly higher risk of requiring allogeneic blood transfusion in perioperative and critically ill patients. An adequately powered randomised controlled trial with economic analysis is needed before gelatin solution can be recommended as a routine plasma expander for patients undergoing major surgery or who are critically ill.
Blood Loss and Replacement for Paediatric Cranioplasty in Australia – A Prospective National Audit
Authors: Howe P. W. , Cooper M. G.
Published: January 2019

We prospectively audited blood loss and blood replacement in every child less than 24 months of age undergoing cranioplasty for craniosynostosis in Australia during 2008, in order to obtain more accurate data for the discussion of perioperative transfusion risk. A total of 127 cases were performed at seven centres. There were no directed or autologous blood donations. No patient received preoperative erythropoietin. A total of 233 units of homologous red blood cells were transfused. Overall, 83% of patients received a blood transfusion. This included 100% of patients undergoing cranial vault reconstruction (CVR) and 98% of patients undergoing fronto-orbital advancement (FOA), but only 32% of spring cranioplasty patients. Exposure to no more than one donor was achieved in 60% of FOA patients and 36% of CVR patients. Estimated blood volume loss was more than one blood volume in 36% of CVR and 36% of FOA, but only 12% of spring cranioplasty, and more than two blood volumes in 4% of CVR and 11% of FOA. Differences in surgical technique and volume of surgery between different centres appeared to affect transfusion rates. Children with recognised craniofacial syndromes and those undergoing repeat surgery appeared to have greater blood loss and blood product exposure. There were two cases of sudden massive haemorrhage secondary to dural venous sinus tear, but no death or perioperative cardiac arrest. These findings indicate that blood loss requiring blood product replacement is common in patients <24 months of age undergoing cranioplasty for craniosynostosis, particularly in patients undergoing FOA and CVR.
Incidence of Difficult Intubation in Intensive Care Patients: Analysis of Contributing Factors
Authors: Heuer J. F. , Crozier T. A. , Barwing J. , Russo S. G. , Bleckmann E. , Quintel M. , MÖRer O.
Published: January 2019

Difficulties in endotracheal intubation increase morbidity and mortality in intensive care patients. We studied the problem in surgical intensive care patients with the aim of risk reduction. Patients intubated in the intensive care unit were evaluated. The intubations were performed or supervised by anaesthetists following the algorithm valid at the time of the study. Fifty percent of the 198 intubations were performed by specialist anaesthetists, 41.5% by anaesthesia trainees and 8.5% by surgical trainees. The initial attempt was by direct laryngoscopy (n=173), flexible fibrescope (n=8) or blind nasal technique (n=17). When direct laryngoscopy failed (n=7), intubation was accomplished with an intubating laryngeal mask airway (n=5), Frova stylet (n=1) or fibrescope (n=1). Thirty percent were rated as easy, 47% as moderately easy and 23% as difficult. Difficult intubations were associated with a higher incidence of anatomic anomalies, difficult bag-mask ventilation and severe oxygen desaturation. Every intubation in the ICU setting should be considered potentially difficult. The existing algorithm should be modified to incorporate the American Society of Anesthesiologists difficult airway algorithm adapted to the needs of the intensive care unit. A training program for alternative methods of airway management for difficult intubations should be established.
Premedication with Granisetron Reduces Shivering during Spinal Anaesthesia in Children
Authors: Eldaba A. A. , Amr Y. M.
Published: January 2019

This study evaluates the effect of prophylactic granisetron on the incidence of postoperative shivering after spinal anaesthesia in children. Eighty children, American Society of Anesthesiologists physical status I to II and aged two to five years were scheduled for surgery of the lower limb under spinal anaesthesia. The children were randomised to receive 10 μg/kg granisetron diluted in 10 ml saline 0.9% intravenously (group 1, n=40) or placebo (10 ml 0.9% saline, group 2, n=40) to be given over five minutes just before spinal puncture. Shivering, core temperature and the levels of motor and sensory block were assessed. No patients shivered in group 1. However, six patients shivered in Group 2 (P=0.025). There were no significant differences in the other measured variables between the groups. Granisetron is an effective agent to prevent shivering after spinal anaesthesia in children from two to five years of age.
Postoperative Plasma Paracetamol Levels following Oral or Intravenous Paracetamol Administration: A Double-Blind Randomised Controlled Trial
Authors: Brett C. N. , Barnett S. G. , Pearson J.
Published: January 2019

In day-case surgery paracetamol is commonly given orally preoperatively, or intravenously intraoperatively. In this double-blind randomised controlled trial we investigated which of these methods of administration achieved therapeutic plasma levels most effectively in the early postoperative period. Thirty patients undergoing day case arthroscopy of the knee were randomised to receive either 1.0 g oral paracetamol 30 to 60 minutes preoperatively (20 patients) or 1.0 g intravenous paracetamol intraoperatively (10 patients). Plasma paracetamol levels were measured 30 minutes after arrival in the recovery room. Secondary outcomes included postoperative pain scores, rescue analgesia requirements and duration of stay in the recovery room. All patients receiving the intravenous preparation had plasma levels above the analgesic level compared to less than half (7/20) in the oral group. Mean plasma paracetamol levels were 88.6 μmol/l for the intravenous group and 53.2 μmol/l for the oral group (P=0.0005). There were trends towards reduced rescue analgesia and duration of stay in the recovery room for the intravenous group although not reaching statistical significance. There was no difference in pain scores between groups. Intraoperative administration of 1.0 g of intravenous paracetamol more reliably achieved effective paracetamol levels in the early postoperative period compared to an equal dose given orally preoperatively. Only a minority of patients receiving the 1.0 g oral dose preoperatively had plasma levels in the therapeutic analgesic range.
Prevention of Gastrointestinal Bleeding Due to Stress Ulceration: A Review of Current Literature
Authors: Pilkington K. B. , Wagstaff M. J. D. , Greenwood J. E.
Published: January 2019

Our objective was to audit our current stress ulcer prophylaxis protocol (routine prescription of ranitidine and early enteral feeding) by identifying whether routine prescription of histamine-2 receptor antagonists or proton pump inhibitors as prophylaxis against stress-related mucosal disease and subsequent upper gastrointestinal bleeding is supported in the literature. We also aimed to ascertain what literature evidence supports the role of early enteral feeding as an adjunctive prophylactic therapy, as well as to search for burn-patient specific evidence, since burn patients are at high risk for developing this condition, with the aim of changing our practice.

PubMed and Cochrane databases were searched for relevant articles, yielding seven randomised controlled trials comparing histamine-2 receptor antagonists and proton pump inhibitors in the prevention of upper gastrointestinal bleeding associated with stress-related mucosal disease and three separate meta-analyses.

Despite level 1 clinical evidence, no significant difference in efficacy between histamine-2 receptor antagonists and proton pump inhibitor treatment groups was demonstrated. No significant difference was demonstrated in the incidence of nosocomial pneumonia between the two drugs given in this indication. However, enteral feeding was found to be safe and effective in preventing clinically significant upper gastrointestinal bleeding. Patients able to tolerate feeds demonstrated no additional benefit with concomitant pharmacological prophylactic therapy.

Since all burn patients at the Royal Adelaide Hospital are fed from very early in their admission, the literature suggests that we, like our intensive care unit colleagues, should abolish our reliance on pharmacological prophylaxis, the routine prescription of which is not supported by the evidence.
An Observational Study Exploring Amplitude-Integrated Electroencephalogram and Spectral Edge Frequency during Paediatric Anaesthesia
Authors: Mckeever S. , Johnston L. , Davidson A. J.
Published: January 2019

Processed electroencephalography is used in adults to guide anaesthesia, but the algorithms used may not apply to infants. Knowledge of infants’ electroencephalogram (EEG) responses to anaesthetics is fragmentary. An earlier pilot study suggested amplitude-integrated EEG (aEEG) may be a useful measure of anaesthetic effect. The aim of this study was to determine how aEEG changes between awake and anaesthetised children of varying ages and to compare the response to that seen with Spectral Edge Frequency 90% (SEF90). A prospective observational study of children receiving a general anaesthetic was conducted. Anaesthetic regimen remained at the discretion of the treating anaesthetist. EEG data were collected using the BrainZ ReBrim™ monitor using forehead and biparietal montages. SEF90 and aEEG were compared across age groups, EEG montage and between awake and anaesthetised states.

A total of 178 children (aged 24 days to 14 years) were recruited. All aEEGs were greater during anaesthesia compared to when awake and this difference varied with age. Only children older than two years showed lower SEF90 while anaesthetised compared to when awake. SEF90 from children younger than six months was higher during anaesthesia compared to when awake. Analysis of parietal and forehead EEG montages revealed age-related differences. These findings suggest that SEF90 and aEEG can discriminate between awake and anaesthetised states in older children. In younger children aEEG changes are less pronounced and SEF90 either cannot discriminate between states or responds paradoxically. The aEEG may be marginally better than other EEG parameters in measuring anaesthetic depth in children.
Performance of the PIRO Score for Predicting Mortality in Patients with Ventilator-Associated Pneumonia
Authors: Furtado G. H. , Wiskirchen D. E. , Kuti J. L. , Nicolau D. P.
Published: January 2019

The ventilator-associated pneumonia (VAP) PIRO score is a new scoring system based on the PIRO concept. The aim of this study was to validate the PIRO score against the Acute Physiology and Chronic Health Evaluation (APACHE) II and VAP APACHE II in an independent group of VAP patients. Areas under the receiver operating characteristic curves were compared to determine the tests’ abilities to predict intensive care unit and 28-day mortality. Variables associated with intensive care unit mortality were evaluated. One hundred and forty-eight intensive care unit patients who met radiographic and clinical criteria for VAP were included. The area under the receiver operating characteristic curves for predicting intensive care unit mortality with the PIRO, APACHE II and VAP APACHE II scores were 0.605 (P=0.03), 0.631 (P=0.01) and 0.724 (P P=0.01) for PIRO, 0.633 (P=0.01) for APACHE II and 0.697 (P=0.002) for VAP APACHE II. No differences in area under the receiver operating characteristic curve between scores were found at either endpoint. Variables independently associated with intensive care unit mortality were bacteraemia (adjusted odds ratio 7.16, 95% confidence interval 1.19 to 42.98, P=0.03) and APACHE II (1.06, 1.01 to 1.11, P=0.006). VAP PIRO score was not a good predictor of intensive care unit and 28-day mortality. The low sensitivity and specificity of VAP PIRO score preclude its use clinically.