TITLE: Postoperative weight loss and its clinical significance in patients with adolescent idiopathic scoliosis who undergo spinal fusion INTRODUCTION Several studies demonstrate a comparably lower preoperative weight and body mass index... more
TITLE: Postoperative weight loss and its clinical significance in patients with adolescent idiopathic scoliosis who undergo spinal fusion INTRODUCTION Several studies demonstrate a comparably lower preoperative weight and body mass index (BMI) in adolescents with idiopathic scoliosis (AIS); however, no study has quantified unintentional postoperative weight loss, or established its impact on outcomes, in this already ‘thin’ patient population after major spinal deformity surgery. METHODS Seventy seven consecutive and eligible patients with AIS who underwent posterior spinal fusion (PSF) were prospectively follow-up from hospital admission (Jan 2010-April 2012). Pre- and postoperative anthropometric measurements were collected (weight, height, BMI) and unintentional weight loss from admission to hospital discharge recorded. Clinically severe involuntary weight loss during the hospital stay was defined as >10% loss of initial body weight from admission to hospital discharge. Sociod...
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The objective of this study was to determine the intracranial, cardiovascular and respiratory changes induced by conversion to high-frequency oscillator ventilation from conventional mechanical ventilation at increasing airway pressures.... more
The objective of this study was to determine the intracranial, cardiovascular and respiratory changes induced by conversion to high-frequency oscillator ventilation from conventional mechanical ventilation at increasing airway pressures. In this study, 11 anaesthetized sheep had invasive cardiovascular and intracranial monitors placed. Lung injury was induced by saline lavage and head injury was induced by inflation of an intracranial balloon catheter. All animals were sequentially converted from conventional mechanical ventilation to high-frequency oscillator ventilation at target mean airway pressures of 16, 22, 28, 34 and 40 cm H(2)O. The mean airway pressure was achieved by adjusting positive end expiratory pressure while on conventional mechanical ventilation, and continuous distending pressures while on high-frequency oscillator ventilation. Cerebral lactate production, oxygen consumption and venous oximetry were measured and analysed in relation to changes in transcranial Doppler flow velocity. Transcranial Doppler profiles together with other physiological parameters were measured at each airway pressure. Cerebral perfusion pressure was significantly lower during high-frequency oscillator ventilation than during conventional mechanical ventilation (CMV: 45, 34, 22, 6, 9 mmHg vs. HFOV: 33, 20, 19, 5, 5 mmHg at airway pressures mentioned above, P = 0.02). Intracranial pressure and cerebrovascular resistance increased with increasing intrathoracic pressures (P = 0.001). Cerebral metabolic indices demonstrated an initial increase in anaerobic metabolism followed by a decrease in cerebral oxygen consumption progressing to cerebral infarction as intrathoracic pressures were further increased in a stepwise fashion. Arterial PaCO(2) increased significantly after converting from conventional mechanical ventilation to high-frequency oscillator ventilation (P = 0.001). However, no difference was observed between conventional mechanical ventilation and high-frequency oscillator ventilation when intracranial pressure, metabolic and transcranial Doppler indices were compared at equivalent mean airway pressures. The use of high positive end expiratory pressure with conventional mechanical ventilation or high continuous distending pressure with high-frequency oscillator ventilation increased intracranial pressure and adversely affected cerebral metabolic indices in this ovine model. Transcranial Doppler is a useful adjunct to intracranial pressure and intracranial venous saturation monitoring when major changes in ventilation strategy are adopted.
Research Interests: Carbon Dioxide, Medicine, Humans, Sheep, Female, and 15 moreAnimals, Anesthesia, Clinical Sciences, Pressure, Head injury, Analysis of Variance, Mechanical Ventilation, Oximetry, Mean Airway Pressure, Lactic Acid, Blood Flow Velocity, Oxygen Consumption, Intracranial Pressure, Cerebral Infarction, and Respiration Artificial
BackgroundSurgical procedures to correct larger curve magnitudes >70° in patients with adolescent idiopathic scoliosis (AIS) are still common; despite their increased complexity, limited research has assessed the effect of preoperative... more
BackgroundSurgical procedures to correct larger curve magnitudes >70° in patients with adolescent idiopathic scoliosis (AIS) are still common; despite their increased complexity, limited research has assessed the effect of preoperative curve severity on outcomes.AimThis study aimed to examine the impact of preoperative curves >70° vs. those ≤70° on perioperative, functional and financial outcomes in patients with AIS undergoing posterior spinal fusion (PSF).MethodsSeventy seven eligible AIS patients who underwent PSF were prospectively followed-up, until return to preoperative function was reported. Preoperative curves >70° vs. ≤70° were analysed in relation to surgical duration, estimated blood loss, perioperative complications, length of hospitalisation, return to function and cost of surgical treatment per patient.ResultsSevere preoperative curves >70°, identified in 21 patients (27.3 %), were associated with significantly longer surgical duration (median 6.5 vs. 5 h, p = 0.001) and increased blood loss (median 1250 vs. 1000 ml, p = 0.005)—these patients were 2.1 times more likely to receive a perioperative blood product transfusion (Relative Risk 2.1, CI 1.4–2.7, p = 0.004). Curves >70° were also associated with a significantly delayed return to school/college, and an increased cost of surgical treatment (€33,730 vs. €28,620, p < 0.0001).ConclusionSurgeons can expect a longer surgical duration, greater intraoperative blood loss and double the blood product transfusion risk when performing PSF procedures on AIS patients with curves greater than 70° vs. those ≤70°. Surgical correction for curves >70°, often as a result of lengthy surgical waiting lists, also incurs added expense and results in a partial delay in early functional recovery.
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ABSTRACT Posterior spinal instrumentation and fusion for correction of adolescent idiopathic scoliosis (AIS) typically requires lengthy operating time and may be associated with significant blood loss and subsequent transfusion. This... more
ABSTRACT Posterior spinal instrumentation and fusion for correction of adolescent idiopathic scoliosis (AIS) typically requires lengthy operating time and may be associated with significant blood loss and subsequent transfusion. This study aimed to identify factors predictive of duration of surgery, intraoperative blood loss and transfusion requirements in an Irish AIS cohort. A retrospective review of 77 consecutive patients with AIS who underwent single-stage posterior spinal instrumentation and fusion over a two-year period at two Dublin tertiary hospitals was performed. Data were collected prospectively and parameters under analysis included pre- and postoperative radiographic measurements, intraoperative blood loss, surgical duration, blood products required, laboratory blood values and perioperative complications. Mean preoperative primary curve Cobb angle was 62.3°; mean surgical duration was 5.6 h. The perioperative allogeneic red blood cell transfusion rate was 42.8 % with a median requirement of 1 unit. Larger curve magnitudes were positively correlated with longer fusion segments, increased operative time and greater estimated intraoperative blood loss. Preoperative Cobb angles greater than 70° [Relative Risk (RR) 4.42, p = 0.003] and estimated intraoperative blood loss greater than 1400 ml (RR 3.01, p = 0.037) were independent predictors of red blood cell transfusion risk. Larger preoperative curve magnitudes in AIS increase operative time and intraoperative blood loss; preoperative Cobb angles greater than 70(o) and intraoperative blood loss greater than 1400 ml are predictive of red blood cell transfusion requirement in this patient group.
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Training in the medical specialty of sport and exercise medicine (SEM) is available in many, but not all countries. In 2015, an independent Delphi group, the International Syllabus in Sport and Exercise Medicine Group (ISSEMG), was formed... more
Training in the medical specialty of sport and exercise medicine (SEM) is available in many, but not all countries. In 2015, an independent Delphi group, the International Syllabus in Sport and Exercise Medicine Group (ISSEMG), was formed to create a basic syllabus for this medical specialty. The group provided the first part of this syllabus, by identifying 11 domains and a total of 80 general learning areas for the specialty, in December 2017. The next step in this process, and the aim of this paper was to determine the specific learning areas for each of the 80 general learning areas. A group of 26 physicians with a range of primary medical specialty qualifications including, Sport and Exercise Medicine, Family Medicine, Internal Medicine, Cardiology, Rheumatology and Anaesthetics were invited to participate in a multiple round online Delphi study to develop specific learning areas for each of the previously published general learning areas. All invitees have extensive clinical e...
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Preoperative preparation for the patient with adrenal disorders is directed toward restoring the intravascular volume and the electrolyte concentrations to normal. Hypertension and hypokalemia may be controlled by restricting sodium... more
Preoperative preparation for the patient with adrenal disorders is directed toward restoring the intravascular volume and the electrolyte concentrations to normal. Hypertension and hypokalemia may be controlled by restricting sodium intake and administration of the aldosterone antagonist spironolactone. Patients taking steroids preoperatively must be adequately replaced throughout the perioperative phase at times of maximum stress.
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To identify the effect of perflubron on gas exchange and lung mechanics during high frequency oscillatory ventilation in an animal model. Prospective randomized animal trial. Eighteen Yorkshire swine. Three groups of six animals each were... more
To identify the effect of perflubron on gas exchange and lung mechanics during high frequency oscillatory ventilation in an animal model. Prospective randomized animal trial. Eighteen Yorkshire swine. Three groups of six animals each were investigated: control (high frequency oscillatory ventilation alone), low dose perflubron (high frequency oscillatory ventilation plus perfluoro-octyl bromide [PFOB]-Lo, 1.5 mL/kg), and high dose perflubron (high frequency oscillatory ventilation plus PFOB-Hi, 3 mL/kg). Lung injury was induced with repeated saline lavage and amplified for 1 hr using large tidal volumes. Perflubron (Alliance, CA) or a sham dose (room air) was administered with bronchoscopic guidance. The animals were transitioned to high frequency oscillatory ventilation starting at a mean airway pressure of 15 cm H2O. Mean airway pressure was increased (inflation phase) by 5 cm H2O every 15 mins to a maximum mean airway pressure of 40 cm H2O. During the deflation phase, mean airway pressure was reduced by 5 cm H2O every 15 mins to a mean airway pressure of 15 cm H2O. Oxygenation was improved and pulmonary shunt fraction was reduced for PFOB-Hi compared with the control group only at a mean airway pressure of 15 and 20 cm H2O. At a maximal mean airway pressure of 40 cm H2O, oxygenation was not different between the groups, but pulmonary artery pressures were elevated in both PFOB-groups compared with the control group. During the deflation phase, oxygenation, pulmonary shunt fraction, and pulmonary artery pressures were adversely affected by PFOB-Hi and PFOB-Lo. Although PFOB-Hi compared with the control group improved oxygenation and reduced pulmonary shunt fraction only during the first pressure steps of a formal stepwise recruitment maneuver during high frequency oscillatory ventilation, this effect was not sustained during maximal recruitment. During the deflation phase, both PFOB groups were associated with worse gas exchange compared with the control group. PFOB also produced significant pulmonary hypertension in comparison with the control group.
