Acute respiratory dysfunction syndrome (ARDS), defined as acute hypoxemia accompanied by radiographic pulmonary infiltrates without a clearly identifiable cause, is a major cause of morbidity and mortality after pulmonary resection. The aim of the study was to determine the pre and intraoperative factors associated with ARDS after pulmonary resection retrospectively.
Patients undergoing elective pulmonary resection at Adnan Menderes University Medical Faculty Thoracic Surgery Department from January 2005 to February 2010 were included in this retrospective study. The authors collected data on demographics, relevant co-morbidities, the American Society of Anesthesiologists (ASA) Physical Status classification score, pulmonary function tests, type of operation, duration of surgery and intraoperative fluid administration (fluid therapy and blood products). The primary outcome measure was postoperative ARDS, defined as the need for continuation of mechanical ventilation for greater than 48-hours postoperatively or the need for reinstitution of mechanical ventilation after extubation. Statistical analysis was performed with Fisher exact test for categorical variables and logistic regression analysis for continuous variables.
Of one hundred forty-three pulmonary resection patients, 11 (7.5%) developed postoperative ARDS. Alcohol abuse (p = 0.01, OR = 39.6), ASA score (p = 0.001, OR: 1257.3), resection type (p = 0.032, OR = 28.6) and fresh frozen plasma (FFP)(p = 0.027, OR = 1.4) were the factors found to be statistically significant.
In the light of the current study, lung injury after lung resection has a high mortality. Preoperative and postoperative risk factor were significant predictors of postoperative lung injury.
Deciding to operate on high risk patients suffering catastrophic surgical emergencies can be problematic. Patients are frequently classed as American Society of Anesthesiologists (ASA) grade 5 and, as a result, aggressive but potentially lifesaving intervention is withheld. The aim of our study was to review the short-term outcomes in patients who were classed as ASA grade 5 but subsequently underwent surgery despite this and to compare the ASA scoring model to other predictors of surgical outcome.
All patients undergoing emergency surgery with an ASA grade of 5 were identified. Patient demographics, indications for surgery, intraoperative findings and outcomes were recorded. In addition to the ASA scores, retrospective Portsmouth Physiological and Operative Severity Score for the enUmeration of Mortality and morbidity (P POSSUM) and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were calculated and compared to the observed outcomes.
Nine patients (39%) survived to discharge. ASA grade was a poor predictor of outcome. P POSSUM and APACHE II scores correlated significantly with each other and with observed outcomes when predicting surgical mortality. The median stay for survivors in the intensive care unit was nine days.
In times of an ageing population, the number of patients suffering catastrophic surgical events will increase. Intervention, with little hope of a cure, a return to independent living or an acceptable quality of life, leads to unnecessary end-of-life suffering for patients and their relatives, and consumes sparse resources. The accuracy and reliability of ASA grade 5 as an outcome predictor has been questioned. P POSSUM and APACHE II scoring systems are significantly better predictors of outcome and should be used more frequently to aid surgical decision-making in high risk patients.
ASA 5; Outcome prediction scores; P POSSUM
This study was done to determine the usefulness of the American Society of Anesthesiologists (ASA) classification, the comorbidity Charlson index unadjusted (CCIu),the comorbidity Charlson index adjusted by age (CCIa), and the Glasgow aneurysm score (GAS) for postoperative morbimortality and survival in patients treated with aorto-bifemoral bypass (AFB) for aorto-iliac occlusive disease (AIOD). A series of 278 patients who underwent AFB were restrospectively studied. For the CCIu, CCIa, ASA, and GAS, receiver operating characteristics curve analysis for prediction of morbidity showed area under the curves of 0.61 (p = 0.004), 0.59 (p = 0.026), 0.569 (p = 0.087), and 0.63 (p = 0.001), respectively. Additionally, univariate analysis showed that CCIa (p = 0.016) and GAS (p = 0.006) were associated significantly with an increased risk of developing complications. Furthermore, CCIa (p < 0.001) and GAS (p = 0.001) showed a significant association with survival. Finally, the variable age was related to morbidity (p = 0.004), mortality (p = 0.038), and survival (p < 0.001). The comorbididity and the age should be taken in account in clinical treatment decisions for patients with AIOD. The CCIa and GAS may play a role as predictive factors for postoperative morbidity and survival after AFB.
atherosclerosis; peripheral arterial disease; risk factors; risk-scoring methods
The primary intention of the study was to find out whether Adult Comorbidity Evaluation Index (ACE-27) was better than the American Society of Anaesthesiologists’ (ASA) risk classification system in predicting postoperative morbidity in head and neck oncosurgery. Another goal was to identify other risk factors for complications which are not included in these indexes. Univariate and multivariate analyses were performed on 250 patients to determine the impact of seven variables on morbidity-ACE-27 grade, ASA class, age, sex, duration of anaesthesia, chemotherapy and radiotherapy. In univariate analysis ACE-27 index, ASA score, duration of anaesthesia, radiotherapy and chemotherapy were significant. As both comorbidity scales were significant in univariate analysis they were analyzed together and separately in multivariate analysis to illustrate their individual strength. In the first multivariate analysis (excluding ACE-27 grade) ASA class, duration of anaesthesia, radiotherapy and chemotherapy were significant. The positive predictive value (PPV) of this model to predict morbidity was 60.86% and negative predictive value (NPV) was 77.9%. The sensitivity was 75% and specificity 62.2%. In the second multivariate analysis (excluding ASA class) ACE-27 grade, duration of anaesthesia and radiotherapy were significant. The PPV of this model to predict morbidity was 62.1% and NPV was 76.5%. The sensitivity was 61.6% and specificity 70.9%. In the third multivariate analysis which included both ACE-27 grade and ASA class only ASA class, duration of anaesthesia, radiotherapy and chemotherapy remained significant. In conclusion, ACE-27 grade and ASA class were reliable predictors of major complications but ASA class had more impact on complications than ACE-27 grade.
Morbidity prediction; perioperative complications; surgery
The aim of this study was to evaluate the safety and efficacy of outpatient laparoscopic cholecystectomy (OLC) in a day surgery unit in a teaching hospital. OLC was offered to patients with symptomatic cholelithiasis who met the following established inclusion criteria: ASA (American Society of Anesthesiology) physical status classification class I and II; age: 18 - 70 years; body mass index (BMI) < 30 kg/m2; patient acceptance and cooperation (informed consent); presence of a responsible adult to accompany the patient to his residency; patient residency in Athens. The primary study end-point was to evaluate success rates (patient discharge on the day of surgery), postoperative outcome (complications, re-admissions, morbidity and mortality) and patient satisfaction. A secondary endpoint was to evaluate its safe performance under appropriate supervision by higher surgical trainees (HSTs).
110 consecutive patients, predominantly female (71%) and ASA I (89%) with a mean age 40.6 ± 8.1 years underwent an OLC. Surgery was performed by a HST in 90 patients (81.8%). A mean postoperative pain score 3.3 (range 0-6) occurred in the majority of patients and no patient presented postoperative nausea or vomiting. Discharge on the day of surgery occurred in 95 cases (86%), while an overnight admission was required for 15 patients (14%). Re-admission following hospital discharge was necessary for 2 patients (1.8%) on day 2, due to persistent pain in the umbilical trocar site. The overall rate of major (trocar site bleeding) and minor morbidity was 15.5% (17 patients). At 1 week follow-up, 94 patients (85%) were satisfied with their experience undergoing OLC, with no difference between grades of operating surgeons.
This study confirmed that OLC is clinical effective and can be performed safely in a teaching hospital by supervised HSTs.
Inadvertent hypothermia is not uncommon in the immediate postoperative period and it is associated with impairment and abnormalities in various organs and systems that can lead to adverse outcomes. The aim of this study was to estimate the prevalence, the predictive factors and outcome of core hypothermia on admission to a surgical ICU.
All consecutive 185 adult patients who underwent scheduled or emergency noncardiac surgery admitted to a surgical ICU between April and July 2004 were admitted to the study. Tympanic membrane core temperature (Tc) was measured before surgery, on arrival at ICU and every two hours until 6 hours after admission. The following variables were also recorded: age, sex, body weight and height, ASA physical status, type of surgery, magnitude of surgical procedure, anesthesia technique, amount of intravenous fluids administered during anesthesia, use of temperature monitoring and warming techniques, duration of the anesthesia, ICU length of stay, hospital length of stay and SAPS II score. Patients were classified as either hypothermic (Tc ≤ 35°C) or normothermic (Tc> 35°C). Univariate analysis and multiple regression binary logistic with an odds ratio (OR) and its 95% Confidence Interval (95%CI) were used to compare the two groups of patients and assess the relationship between each clinical predictor and hypothermia. Outcome measured as ICU length of stay and mortality was also assessed.
Prevalence of hypothermia on ICU admission was 57.8%. In univariate analysis temperature monitoring, use of warming techniques and higher previous body temperature were significant protective factors against core hypothermia. In this analysis independent predictors of hypothermia on admission to ICU were: magnitude of surgery, use of general anesthesia or combined epidural and general anesthesia, total intravenous crystalloids administrated and total packed erythrocytes administrated, anesthesia longer than 3 hours and SAPS II scores. In multiple logistic regression analysis significant predictors of hypothermia on admission to the ICU were magnitude of surgery (OR 3.9, 95% CI, 1.4–10.6, p = 0.008 for major surgery; OR 3.6, 95% CI, 1.5–9.0, p = 0.005 for medium surgery), intravenous administration of crystalloids (in litres) (OR 1.4, 95% CI, 1.1–1.7, p = 0.012) and SAPS score (OR 1.0, 95% CI 1.0–1.7, p = 0.014); higher previous temperature in ward was a significant protective factor (OR 0.3, 95% CI 0.1–0.7, p = 0.003). Hypothermia was neither a risk factor for hospital mortality nor a predictive factor for staying longer in ICU.
The prevalence of patient hypothermia on ICU arrival was high. Hypothermia at time of admission to the ICU was not an independent factor for mortality or for staying longer in ICU.
Objective To evaluate the effect of comorbidity and other risk factors on postoperative mortality and morbidity in patients undergoing major oesophageal and gastric surgery.
Design Multicentre cohort study with data on postoperative mortality and morbidity in hospital.
Data source and methods The ASCOT prospective database, comprising 2087 patients with newly diagnosed oesophageal and gastric cancer in 24 hospitals in England and Wales between 1 January 1999 and 31 December 2002. Multivariate logistic regression analysis was used to model the risk of death and postoperative complications.
Results 955 patients underwent oesophagectomy or gastrectomy. Of these, 253 (27%) were graded ASA III or IV, and 187 (20%) had a high physiological POSSUM score (≥ 20). Operative mortality was 12% (111/955). Physiological POSSUM score, surgeon's assessment, type of operation, hospital case volume, and tumour stage independently predicted operative mortality. Medical complications were associated with higher physiological POSSUM scores and ASA grade, oesophagectomy or total gastrectomy, thoracotomy, and radical nodal dissection. Stage and additional organ resection predicted surgical (technical) complications.
Conclusions Many patients undergoing surgery for gastro-oesophageal cancer have major comorbid disease, which strongly influences their risk of postoperative death. Technical complications do not seem to be influenced by preoperative factors but reflect the extent of surgery and perhaps surgical judgment. Detailed prospective multicentre cooperative audit, with appropriate risk adjustment, is fundamental in the evaluation of cancer care and must be properly resourced.
The aim of this study was to evaluate the management of postoperative pain at the Niamey National Hospital.
A prospective study was conducted in the Department of Anesthesiology and Intensive Care at the Niamey National Hospital from March to June, 2009. Data collected included age, sex, literacy, American Society of Anesthesiologists (ASA) physical status classification, type of anesthesia, type of surgery, postoperative analgesics used, and the cost of analgesics. Three types of pain assessment scale were used depending on the patient’s ability to describe his or her pain: the verbal rating scale (VRS), the numerical rating scale (NRS), or the visual analog scale (VAS). Patients were evaluated during the first 48 hours following surgery.
The sample included 553 patients. The VRS was used for the evaluation of 72% of patients, the NRS for 14.4%, and the VAS for 13.6%. Of the VRS group, 33.9%, 8.3%, and 2.1% rated their pain as 3 or 4 out of 4 at 12, 24, and 48 hours postoperatively, respectively. For the NRS group, 33.8%, 8.8%, and 2.5% rated their pain as greater than 7 out of 10 at 12, 24, and 48 hours postoperatively, respectively. For the VAS group, 29.3%, 5.4%, and 0% rated their pain as greater than 7 out of 10 at 12, 24, and 48 hours postoperatively, respectively.
Postoperative pain assessment and management in developing countries has not been well described. Poverty, illiteracy, and inadequate training of physicians and other health personnel contribute to the underutilization of postoperative analgesia. Analysis of the results gathered at the Niamey National Hospital gives baseline data that can be the impetus to increase training in pain management and to establish standardized protocols.
postoperative pain; pain scales; Niamey National Hospital
To test the Italian translation of Corah's Dental Anxiety Scale (DAS) and to check the relationship between dental anxiety and the American Society of Anesthesiologists (ASA) physical status classification (ASA-PS), the DAS was translated into Italian and administered to 1072 Italian patients (620 male and 452 female patients, ages 14–85 years) undergoing oral surgery. Patients' conditions were checked and rated according to the ASA-PS. The DAS ranged from 4 to 20 (modus = 8, median = 10); 59.5% of patients had a DAS of 7–12, 26.1% had a DAS >12, and 10.3% had a DAS >15. The mean DAS was 10.29 (95% confidence limit = 0.19); female patients were more anxious than male patients (P < .001), while patients older than 60 years showed a significant decrease in the level of anxiety. Five hundred two patients were rated as ASA-PS class P1, 502 as ASA-PS class P2, and 68 as ASA-PS class P3, with a mean DAS score of 9.69, 10.78, and 11.09, respectively: the DAS difference between groups was significant (P < .001).
Anxiety; Dentistry; Dental anxiety scale; Visual analogue scale; Psychological tests; Methods; Dental phobia; Physical status
The incidence of difficulty in tracheal intubation has been reported to range from 0.5 to 18% in patients undergoing surgery. We aimed to elucidate the role of upper lip bite test (ULBT) with other prevailing tests, hyomental/thyrosternal distances (HMD/TSD), and the mandible length (ML) and their possible correlation in predicting difficulty in intubation. After institutional approval and informed consent were obtained, 300 consecutive patients aged 20–60 years of ASA physical status I and II, scheduled for elective surgical procedures requiring tracheal intubation and meeting the inclusion criteria, were enrolled in this study. Each patient was evaluated regarding ULBT, HMD, TSD and ML. Laryngoscopy was assessed by an attending anaesthesiologist blinded to the measurements. The laryngoscopic result was graded according to Cormack and Lehane’s Grading system. The negative predictive value (NPV) and positive predictive value (PPV) of ULBT were found to be 94 and 100%, respectively. These corresponding figures for TSD were 88.5 and 0%, respectively. Specificities for ULBT, HMD, ML and TSD were 100, 98.9, 98.9 and 98.1%, respectively. ULBT class and laryngoscopic grading showed the greatest agreement (kappa = 0.61, P < 0.001). An agreement between laryngoscopic grading and HMD and ML also existed (0.003 and <0.001, respectively), but was comparatively weaker. The high specificity, NPV, PPV and accuracy of ULBT as revealed in this study could be a good rationale for its application in the prediction of difficulty or easiness in intubation. ML > 9 cm and HMD > 3.5 cm were good predictors of negative difficult intubation.
Difficult intubation; difficult laryngoscopy; endotracheal intubation; predictive airway tests
The system used by the National Nosocomial Infection Surveillance (NNIS) program to measure risk of surgical site infection uses a score of 3 on the American Society of Anesthesiologists (ASA)-physical status scale as a measure of underlying illness. The chronic disease score measures health status as a function of age, sex, and 29 chronic diseases, inferred from dispensing of prescription drugs. We studied the relationship between the chronic disease score and surgical site infection and whether the score can supplement the NNIS risk index. In a retrospective comparison of 191 patients with surgical site infection and 378 uninfected controls, the chronic disease score and ASA score were highly correlated. The chronic disease score improved prediction of infection by the NNIS risk index and augmented the ASA score for risk adjustment.
Prediction of outcome after cardiac surgery is difficult despite a number of models using pre-, intra- and post-operative factors. Ideally, risk factors operating in all three phases of the patients’ stay in the hospital should be incorporated into any outcome prediction model. The aim of the present study was to identify the perioperative risk factors associated with morbidity, mortality and length of stay in the recovery room (LOSR) and length of stay in the hospital (LOSH).
Eighty-eight adults of either sex, patients undergoing elective open cardiac surgery were studied prospectively. The ability of a number of pre-, intra- and post-operative factors to predict outcome in the form of mortality, immediate morbidity (LOSR) and intermediate morbidity (LOSH) was assessed.
Factors associated with higher mortality were preoperative prothrombin index (PTI), American Society of Anesthesiology-Physical Status (ASA-PS) grade, Cardiac Anaesthesia Risk Evaluation (CARE) score and New York Heart Association (NYHA) class, intraoperative duration of cardiopulmonary bypass (DCPB), number of inotropes used while coming off cardiopulmonary bypass and postoperatively, Acute Physiology and Chronic Health Evaluation (APACHE) II excluding the Glassgow Comma Scale (GCS) component and the number of inotropes used. Immediate morbidity was associated with preoperative PTI, inotrope usage intra- and post-operatively and the APACHE score. Intermediate morbidity was associated with DCPB and intra- and post-operative inotrope usage. Individual surgeon influenced the LOSR and the LOSH.
APACHE score, a general purpose severity of illness score, was relatively ineffective in the postoperative period because of sedation, neuromuscular blockade and elective ventilation used in a number of these patients. The preoperative and intraoperative factors like CARE, ASA-PS grade, NYHA, DCPB and number of inotropes used influencing morbidity and mortality are consistent with the literature, despite the small size of our sample.
Cardiac surgery; outcome prediction; prognostication; risk stratification
Head and neck reconstruction is often mandatory in elderly and ill patients, especially after tumor ablation. Even complex reconstructive procedures can be done in the elderly population after careful evaluation. The morbidity and mortality rates increase with age, thus the risks and benefits of surgical intervention must be weighed precisely. The functional capacities of the vital organs and the limitations should be assessed. The only significant preoperative guide for the risk of the operation is the American Society of Anesthesiologists (ASA) score. According to this scoring system, ASA 3 and 4 patients are more prone to complications. For a successful reconstructive procedure in old and ill patients, detailed preoperative evaluation is mandatory. Based on this evaluation, the type and duration of the surgery can be properly selected, and postoperative monitoring can be handled individually.
ASA score; elderly patients; operative risk; preoperative assessment
Objectives—To evaluate the performance of a patient assessed outcome measure, the Oxford Hip Score, in a national study of primary hip replacement surgery.
Design—A survey of patients' health status before undergoing primary hip replacement surgery and three months and one year after surgery.
Setting—143 hospitals in three NHS English regions.
Patients—7151 patients admitted for primary total hip replacement surgery over a period of 13 months from September 1996.
Main measures—For patients, Oxford Hip Score and satisfaction with hip replacement and, for surgeons, American Anesthiologists' Society (ASA) classification of physical status.
Results—The response rates to the postal questionnaire at three and 12 months follow up were 85.2% and 80.7%, respectively. Including all three administrations of the questionnaire, all except two items of the Oxford Hip Score were completed by 97% or more respondents and only one item at one administration appeared marginally to reduce the reliability of the score. The effect sizes for changes in the score from baseline to three months was 2.50 and to 12 months was 3.05. Patients rated by surgeons as being healthy preoperatively by the ASA classification were somewhat more likely to return a completed questionnaire at three months (79.4% versus 75.3%) and 12 months (72.4% versus 70.3%) than those rated as having poorer health.
Conclusions—Overall there was little evidence of difficulties for patients in completing the Oxford Hip Score or of unreliable data, except in relation to one questionnaire item. The instrument was very responsive to change over time and score changes for the Oxford Hip Score related well to patients' satisfaction with their surgery. The instrument is an appropriate measure in terms of validity, responsiveness, and feasibility for evaluating total hip replacement from the perspective of the patient.
Key Words: total hip replacement surgery; Oxford Hip Score; questionnaire; assessment
Reduced lung volumes and atelectasis are common after open-heart surgery, and pronounced restrictive lung volume impairment has been found. The aim of this study was to investigate factors influencing lung volumes on the second postoperative day. Open-heart surgery patients (n = 107, 68 yrs, 80% male) performed spirometry both before surgery and on the second postoperative day. The factors influencing postoperative lung volumes and decrease in lung volumes were investigated with univariate and multivariate analyses. Associations between pain (measured by numeric rating scale) and decrease in postoperative lung volumes were calculated with Spearman rank correlation test. Lung volumes decreased by 50% and were less than 40% of the predictive values postoperatively. Patients with BMI >25 had lower postoperative inspiratory capacity (IC) (33 ± 14% pred.) than normal-weight patients (39 ± 15% pred.), (P = 0.04). More pain during mobilisation was associated with higher decreases in postoperative lung volumes (VC: r = 0.33, P = 0.001; FEV1: r = 0.35, P ≤ 0.0001; IC: r = 0.25, P = 0.01). Patients with high BMI are a risk group for decreased postoperative lung volumes and should therefore receive extra attention during postoperative care. As pain is related to a larger decrease in postoperative lung volumes, optimal pain relief for the patients should be identified.
The intubation difficulty scale (IDS) has been used as a validated difficulty score to define difficult intubation (DI). The purpose of this study is to identify airway assessment factors and total airway score (TAS) for predicting DI defined by the IDS.
There were 305 ASA physical status 1-2 patients, aged 19-70 years, who underwent elective surgery with endotracheal intubation. During the pre-anesthetic visit, we evaluated patients by 7 preoperative airway assessment factors, including the following: Mallampati classification, thyromental distance, head & neck movement, body mass index (BMI), buck teeth, inter-incisor gap, and upper lip bite test (ULBT). After endotracheal intubation, patients were divided into 2 groups based on their IDS score estimated with 7 variables: normal (IDS < 5) and DI (IDS ≥ 5) groups. The incidence of TAS (> 6) and high score of each airway assessment factor was compared in two groups: odds ratio, confidence interval (CI) of 95%, with a significant P value ≤ 0.05.
The odds ratio of TAS (> 6), ULBT (class III), head & neck movement (< 90°), inter-incisor gap (< 4 cm), BMI (≥ 25 kg/m2) and Mallampati classification (≥ class III) were respectively 13.57 (95% CI = 2.99-61.54, P < 0.05), 12.48 (95% CI = 2.50-62.21, P < 0.05), 3.11 (95% CI = 0.87-11.13), 2.32 (95% CI = 0.75-7.19), 2.22 (95% CI = 0.81-6.06), and 1.22 (95% CI = 0.38-3.89).
We suggest that TAS (> 6) and ULBT (class III) are the most useful factors predicting DI.
Anesthesia; Evaluation studies; Intubation
Examining the quality of life (QOL) of patients before ICU admission will allow outcome variables to be compared and analyzed in relation to it. The objective of this study was to analyze QOL of patients before admission to a surgical ICU and to study its relationship to outcome and to the baseline characteristics of the patients.
All adult patients consecutively admitted to the surgical ICU between November 2004 and April 2005, who underwent non-cardiac surgery, were enrolled in this observational and prospective study. The following patient characteristics were recorded: age, gender, body mass index, ASA physical status, type and magnitude of surgical procedure, length of stay (LOS), in ICU and in hospital, mortality, Simplified Acute Physiology Score II (SAPS), history of co-morbidities and quality of life survey score (QOLSS). The relationships between QOLSS and ICU variables and outcome were evaluated. The relationship between the total QOLSS and each variable or outcome was assessed by multiple linear regression.
One hundred eighty seven patients completed the study. The preadmission QOLSS of the patients studied was 4.43 ± 4.90; 28% of patients had a normal quality of life (0 points), 38% had between 1 and 5 points (considered mild deterioration), 21% had between 6 and 10 points (moderate deterioration), 10% had between 11 and 15 points (considered major deterioration) and 3% had more than 15 points (severe limitation of quality of life). A worse preadmission QOLSS was associated with higher SAPS II scores, with older patients (age> 65 years) and with ASA physical status (ASA III/IV). Total QOLSS was significantly worse in elderly patients and in patients with co-morbidities and in patients more severely ill at ICU admission. Patients who died in the ICU and in hospital had worse QOLSS scores compared to those who survived. However, no statistical differences in QOLSS were found in relation to longer ICU stays (ICU LOS).
Preadmission QOL correlates with age and severity of illness. Patients with co-morbidities and those who died during ICU or hospital stay had worse QOLSS scores.
Prediction of protein solvent accessibility, also called accessible surface area (ASA) prediction, is an important step for tertiary structure prediction directly from one-dimensional sequences. Traditionally, predicting solvent accessibility is regarded as either a two- (exposed or buried) or three-state (exposed, intermediate or buried) classification problem. However, the states of solvent accessibility are not well-defined in real protein structures. Thus, a number of methods have been developed to directly predict the real value ASA based on evolutionary information such as position specific scoring matrix (PSSM).
This study enhances the PSSM-based features for real value ASA prediction by considering the physicochemical properties and solvent propensities of amino acid types. We propose a systematic method for identifying residue groups with respect to protein solvent accessibility. The amino acid columns in the PSSM profile that belong to a certain residue group are merged to generate novel features. Finally, support vector regression (SVR) is adopted to construct a real value ASA predictor. Experimental results demonstrate that the features produced by the proposed selection process are informative for ASA prediction.
Experimental results based on a widely used benchmark reveal that the proposed method performs best among several of existing packages for performing ASA prediction. Furthermore, the feature selection mechanism incorporated in this study can be applied to other regression problems using the PSSM. The program and data are available from the authors upon request.
Objective To develop a mathematical model that will predict the probability of death after surgery for colorectal cancer.
Design Descriptive study using routinely collected clinical data.
Data source The database of the Association of Coloproctology of Great Britain and Ireland (ACPGBI), encompassing 8077 patients with a new diagnosis of colorectal cancer in 73 hospitals during a 12 month period.
Statistical analysis A three level hierarchical logistic regression model was used to identify independent predictors of operative mortality. The model was developed on 60% of the patient population and its validity tested on the remaining 40%.
Results Overall postoperative mortality was 7.5% (95% confidence interval 6.9% to 8.1%). Independent predictors of death were age, American Society of Anesthesiology (ASA) grade, Dukes's stage, urgency of the operation, and cancer excision. When tested the predictive model showed good discrimination (area under the receiver operating characteristic curve = (0.775) and calibration (comparison of observed with expected mortality across different procedures; Hosmer-Lemeshow statistic = 6.34, 8 df, P = 0.610).
Conclusions Clinicians can predict postoperative death by using a simple numerical table derived from the statistical model of the ACPGBI. The model can be used in everyday practice for preoperative counselling of patients and their carers as a part of multidisciplinary care. It may also be used to compare the outcomes between multidisciplinary teams for colorectal cancer.
Shivering-the “Big Little Problem” has an incidence of 60% in early recovery phase following general anaesthesia. A number of techniques have been tried to prevent postoperative shivering. Previous study showed that, ondansetron in higher doses reduces postoperative shivering. Therefore, this study was done to compare the efficacy of prophylactic granisetron, pethidine and placebo in preventing postoperative shivering.
Ninety patients aged 20-60yrs, ASA physical status I and II, scheduled for laparoscopic surgery under general anaesthesia were randomly allocated to receive either normal saline (Group S, n=30) as negative control, pethidine 25mg (Group P, n=30) as positive control or granisetron 40mcg.kg−1 (Group G, n=30) intravenously before induction. The anaesthesia was induced with fentanyl 2mcg.kg−1, propofol 2mg.kg−1 and atracurium 0.5mg.kg−1 and maintained with sevoflurane 1 - 1.5%. Nasopharyngeal temperature was measured throughout the procedure. An investigator, blinded to the treatment group, graded postoperative shivering in a scale of 0 to 4. (0= no shivering, 1= piloerection or peripheral vasoconstriction but no visible shivering, 2= muscle activity in only one muscle group 3= muscle activity in more than one muscle group, 4= shivering involving the whole body). Prophylaxis was regarded as ineffective if shivering was greater than grade 3 and intravenous pethidine 25 mg was administered as rescue medication.
The three groups did not differ significantly regarding patient characteristics. The numbers of patients shivering on arrival in the recovery room at 15 minutes after operation were significantly less in Group P (7%) and Group G (17%) than in Group S (60%). Groups P and G differ significantly than in Group S (p<0.05). However, the difference between Groups P and G was not statistically significant (p>0.05). The prophylactic use of granisetron (40mcg.kg−1) and pethidine(25mg) intravenous were found to be effective in preventing postoperative shivering.
Shivering; Postoperative; Granisetron; Pethidine
Adequacy of postoperative analgesia is one of the most important factors that determine early hospital discharge and patients’ ability to resume their normal activities postoperatively. The optimal non-opioid analgesic technique for postoperative pain management would reduce pain and enhance patient satisfaction, and it also facilitates earlier mobilization and rehabilitation by reducing pain-related complications after surgery. The aim of this study was to evaluate the analgesic efficacy of intravenous paracetamol and parecoxib when used alone, or in combination.
Sixty American Society of Anesthesiology (ASA) physical status I and II adult patients who were scheduled for anterior cruciate ligament reconstruction were included in this study. Patients were allocated into three groups: group I patients received 1g intravenous paracetamol after induction and another 1 g 4 h later, group II received 40 mg parecoxib after induction, while group III received combination of both drugs (paracetamol 1 g and parecoxib 40 mg). Pain during rest and mobility was assessed in the immediate postoperative period, 2 h and 8 h successively using visual analog scale (VAS). Patient satisfaction was rated according to satisfaction score.
Total morphine requirements were lower in group III patients (6.9±2.7 mg) in comparison to group I patients (12.6±3.6 mg) or group II patients (9.8±2.8 mg). The least VAS scores were recorded during knee movement (3.8±1.1) in group III patients compared to group I (6.0±1.8) and group II patients (4.8±1.9). Eight hours postoperatively, group III patients were more satisfied regarding the postoperative pain management.
Combination of intravenous paracetamol and parecoxib provided better analgesia and higher patient satisfaction than each drug when used separately.
Intravenous paracetamol; parecoxib; postoperative analgesia
Acute kidney injury (AKI) after coronary artery bypass graft (CABG) surgery is associated with increased postoperative morbidity and mortality. We hypothesized that increased plasma neutrophil gelatinase-associated lipocalin (NGAL) measured immediately after separating from cardiopulmonary bypass (CPB) would predict AKI after CABG surgery.
In a retrospective observational study, we examined the value of plasma NGAL measured after CPB for predicting the risk of developing AKI (defined as a ≥50% increase in serum creatinine from preoperative levels) in 879 patients after CABG surgery using multivariable logistic regression. Area under the curve of receiver operating characteristic curves was analyzed to assess sensitivities, specificities, and cutoff points for postoperative plasma NGAL levels to predict AKI.
Seventy-five patients (8.6%) developed postoperative AKI. Plasma NGAL levels measured after CPB were higher in patients who subsequently developed AKI than in those who did not (AKI: 268.8 ng/mL [207.5–459.5 ng/mL], median [interquartile range], vs no AKI: 238.4 ng/mL [172.0–319.1 ng/mL]; P < 0.001) and remained higher through postoperative day 4. An optimal serum plasma NGAL cutoff of 353.5 ng/mL at the post-CPB time point had a sensitivity of 38.7%, specificity of 81.5%, and a positive predictive value of 16.3% for predicting AKI. In our multivariate regression model, post-CPB plasma NGAL levels >353.5 ng/mL were independently associated with postoperative AKI (odds ratio, 2.3; 95% confidence interval, 1.5–6.5; P = 0.002).
An early increase of post-CPB plasma NGAL is associated with AKI in adult patients undergoing CABG surgery, although the sensitivity is low. Therefore, assessing early plasma NGAL alone has limited utility for predicting AKI in this patient population.
The first option for gallbladder surgery is laparoscopic cholecystectomy. The aim of this study is to analyze the outcomes for all patients who underwent laparoscopic cholecystectomy at a secondary level of care.
Patients and Methods:
Between 2005 and 2008, 968 consecutive laparoscopic cholecystectomies were performed at King Fahad Hospital. We collected and analyzed data including age, gender, body mass index (kg/m2), the American Society of Anesthesiologists (ASA) class, mode of admission (elective or emergency), indication for LC (chronic or acute cholecystitis [AC]), co-morbid disease, previous abdominal surgery, conversion to open cholecystectomy, complications, operation time, and length of postoperative hospital stay.
Nine hundred and sixty-eight patients had laparoscopic cholecystectomy at the center. There were 824 females and 144 males; the age range was 15-64 (mean 32.9± 12.7 years). The operating time was 45 to 180 min (median 85 min); the complication rate was 4.03% (39 patients).
Laparoscopic cholecystectomy could be performed safely in the majority of patients with cholelithiasis, by an experienced surgical team at a secondary level of care.
Complications; laparoscopic cholecystectomy; morbidity
Due to the increase of cardiovascular diseases acetylsalicylic acid (ASA) has become one of the most frequently prescribed drugs these days. Despite the rising number of patients with ASA medication presenting for elective general and abdominal surgery and the potentially increased risk of hemorrhage in these patients, there are no clear, evidence-based guidelines for the perioperative use of antiplatelet agents. The present randomised controlled trial was designed to evaluate the safety and optimize the use of ASA in the perioperative management of patients undergoing general and abdominal surgery.
This is a two-arm, monocenter randomised controlled trial. Patients scheduled for elective surgical treatment (i.e. inguinal hernia repair, cholecystectomy and colorectal resections) with ASA as a permanent medication are randomised equally to perioperative continuation or discontinuation of ASA. Patients who are randomised in the discontinuation group stop the administration of ASA five days prior to surgical treatment and start intake of ASA on postoperative day 5. Fifty-two patients will be enrolled in this trial. The primary outcome is the incidence of postoperative bleeding and cardiovascular events at 30 days after surgery. In addition a set of general as well as surgical variables are analysed.
This is a randomised controlled two-group parallel trial designed to assess the safety and optimize the use of ASA in the perioperative management of patients undergoing general and abdominal surgery. The results of this pilot study build the basis for a confirmative randomised controlled trial that may help to clarify the use and potential risk/benefits of perioperative ASA medication in patients undergoing elective surgery.
The trial is registered with Current Controlled Trials ISRCTN45810007.
We compared the prophylactic effects of intravenously administered azasetron (10 mg) and ondansetron (8 mg) on postoperative nausea and vomiting (PONV) in patients undergoing gynecological laparoscopic surgery under general anesthesia.
Materials and Methods
We studied 98 ASA physical status I or II 20-65 years old, female patients, in this prospective, randomized, double blind study. Patients were randomly divided into two groups and received ondansetron 8 mg (group O) or azasetron 10 mg (group A) 5 min before the end of surgery. The incidence of PONV, Visual Analogue Scale (VAS) for pain, need for rescue antiemetic and analgesics, and adverse effects were checked at 1, 6, 12, 24, and 48 h postoperatively.
The overall incidence of PONV was 65% in group O and 49% in group A. The incidence of PONV was significantly higher in group O than in group A at 12-24 h postoperatively (nausea; 24% vs. 45%, p = 0.035, vomiting; 2% vs. 18%, p = 0.008), but there were no significant differences at 0-1, 1-6, 6-12 or 24-48 h.
In conclusion, azasetron (10 mg) produced same incidence of PONV as ondansetron (8 mg) in patients undergoing general anesthesia for gynecological laparoscopic surgery. Azasetron was more effective, in the intermediate post-operative period, between 12 and 24 h.
Azasetron; gynecologic surgical procedures; ondansetron; postoperative nausea and vomiting; prophylaxis