Vol 4 No 4 (2018): Autumn
Assessing Impaired Oxygenation through Evaluating Cough Frequency and Duration at Extubation in the Post-anesthesia Phase
Background: Atelectasis is one of the most common postoperative respiratory complications following general anesthesia. It occurs mainly in 85% to 90% of patients who undergo general anesthesia. Postoperative atelectasis occurs due to diaphragmatic dysfunction, impaired surfactant activity, coughing at the end of anesthesia, and disturbance in (A-a) GO2 (alveolar-arterial oxygen partial pressure gradient). The aim of this study was to evaluate the effect and duration of coughing on impaired oxygenation and atelectasis after emergence from general anesthesia under mechanical ventilation in post-anesthetic care unit.
Methods: In this prospective study, 97 patients undergoing general anesthesia and mechanical ventilation were enrolled. Quantitative and qualitative demographic data were collected through questionnaires. Arterial blood samples were taken 30 minutes before the end of the surgery and one hour after the completion of operation to measure the alveolar -arterial gradient. Data analysis was performed using SPSS-16 software, t-test and qui square test. P value <0.05 was considered statistically significant.
Results: The number of coughs before extubation or after extubation and increased duration of coughing could result in significantly increased arterial alveolar gradient.
Conclusion: Increased frequency of coughing during emergence from anesthesia and extubation results in increased Arterial - alveolar oxygen partial pressure gradient (A-a) GO2 and also the prevalence of atelectasis in post-anesthesia care unit.
Use of the APACHE II Score for the Assessment of Outcome and Mortality Prediction in an Iranian Medical-Surgical Intensive Care Unit
Background: The Acute Physiology and Chronic Health Evaluation (APACHE) II is still commonly used as an index of illness severity in patients admitted to intensive care unit (ICU) and has been validated in many research and clinical audit purposes.
The aim of this study is to investigate the diagnostic value of APACHE II score for predicting mortality rate of critically ill patients.
Methods: This was a retrospective cross-sectional study of 200 patients admitted in the medical-surgical adult ICU. Demographic data, pre-existing comorbidities, and required variables for calculating APACHE II score were recorded. Receiver operating characteristic (ROC) curves were constructed and the area under the ROC curves was calculated to assess the predictive value of the APACHE II score of in-hospital mortality.
Results: Of the 200 patients with mean age of 55.27 ± 21.59 years enrolled in the study, 112 (54%) were admitted in the medical ICU, and 88 (46%) in the surgical ICU. Finally, 116 patients (58%) died and 84 patients (42%) survived. The overall actual and predicted hospital mortality were 58% and 25.16%, respectively. The mean APACHE II score was 16.31 in total patients, 17.78 in medical ICU, and 14.45 in surgical ICU, and the difference was statistically significant between the two groups (P= 0.003). Overall, the area under ROC curve was 0.88. APACHE II with a score of 15 gave the best diagnostic accuracy to predict mortality of patients with a sensitivity, specificity, positive and negative predictive values of 85.3%, 77.4%, 83.9%, and 73.9%, respectively.
Conclusion: Despite significant progress has been made in recent decades in terms of technology and equipment, therapeutics and process of care and identifies in the ICU setting, these scientific efforts have not directly led to a further reduction in mortality for patients hospitalized in the ICU.
Comparative Evaluation of ProSeal LMA vs. Cuffed Endotracheal Tube in Patients Undergoing Laparoscopic Cholecystectomy under General Anesthesia
Background: Proseal LMA (PLMA) has been used for airway maintenance during laparoscopic cholecystectomy. However, there is limited data regarding the effects of pneumoperitoneum, particularly on pulmonary mechanics. Objective of the present study was to evaluate and compare the use of PLMA with a cuffed endotracheal tube (ETT) with regard to changes in pulmonary mechanics, haemodynamic variables, degree of gastric inflation, ease of device insertion and possible adverse events in patients undergoing laparoscopic cholecystectomy.
Methods: After written informed consent and institutional ethics committee approval, we enrolled one hundred patients (ASA physical status1/2), 18-60 years of age who were scheduled to undergo laparoscopic cholecystectomy under general anesthesia (GA). Patients were randomly allocated to one of the two groups of 50 each. Group 1: cuffed endotracheal tube and Group 2: ProSeal LMA. Patients as well as the surgeons were blinded to the airway device used. Insertion parameters, haemodynamic and ventilatory parameters (compliance, resistance and peak/plateau airway pressure) were measured at different time intervals before, during and after pneumoperitoneum.
Results: Statistically significant (p< 0.05) but clinically insignificant difference was found in time taken for device insertion in the two groups (21.8 ± 5.9 s group I & 25.4 ± 5.7 s group II). Insertion of orogastric tube was easier and less number of attempts was required with PLMA. Hemodynamic parameters like heart rate, systolic, diastolic and mean blood pressures increased after the ETT insertion while there was a decrease/no change after PLMA insertion. There was a significant decline in the pulmonary compliance in Group 2, which was more pronounced after pneumoperitoneum. During pneumoperitoneum, higher peak and plateau airway pressures were noted in PLMA group than in ETT group. After desufflation these parameters returned to near pre-insufflation levels. There was no episode of arterial desaturation or end tidal carbon dioxide changes in either group.
Conclusion: Our results indicate that in the PLMA group, the degree of changes in pulmonary mechanics caused by the pneumoperitoneum were significant however there was no incidence of arterial desaturation, or gastric regurgitation. Due to better hemodynamic stability with PLMA, it may even be better alternative than ETT in hypertensive/cardiac patients. Hence PLMA is a satisfactory airway device for laparoscopic cholecystectomy under GA, but further studies are required regarding its safety in patients with decreased pulmonary compliance like morbid obesity or obstructive pulmonary disease.
Evaluation of Acute and Chronic Back Pain After Spinal Anesthesia in Midline and Paramedian Approach: Incidence and Functional Disability
Background: The intensity of low back pain and functional disability in life is a common question of patients before spinal anesthesia. We aimed to compare acute and chronic back pain after spinal anesthesia in midline and paramedian approach.
Methods: Two hundred twenty patients elective patients (25-65 year old) candidates for general, and urological surgery under spinal anesthesia, were allocated into the following two groups: Group M (midline) and Group P (paramedian). Spinal anesthesia was performed with hyperbaric bupivacaine 0.5% in the sitting position using a 25G Quincke needle in L3/L4 orL4/L5 level. During the operation, patients were placed in the supine position. The questionnaire assessed back pain and severity of pain with VAS score three days after spinal anesthesia. If the patients complained of back pain then, the effect of back pain on quality of life and the degree of patient's functional disability were assessed by Oswestry Disability Index on,45 and 90 days after surgery.
Results: Forty-one patients (18%) had back pain after the operation, 22 patients were in the paramedian (54%) and 19 patients (46%) in the midline method of spinal anesthesia. (p=0.6). The mean intensity of back pain was 2.27vs1.45 (p=0.5) and the total number of mean functional disability index was less than five in both groups.
Conclusion: The incidence of back pain was 18% and was not significantly different between the midline and paramedian methods. The severity of back pain decreased after three days, reaching to less than one on day the 45th and 90th, which does not affect daily patient’s functions.
Comparing the Efficacy of Dexmedetomidine versus Fentanyl and Midazolam During Awake Fiberoptic Intubation
Background: Awake oral flexible fiberoptic intubation (AFOI) is used in patients with expected difficult airways. Different drugs have been used for sedation and yet we need to define ideal drug with proper sedation and safety, less changes in hemodynamic stability and less airway compromise. We aimed to compare the efficacy of dexmedetomidine with fentanyl and midazolam during AFOI.
Methods: In this randomized clinical trial, 52 patients undergoing elective surgery and candidate for AFOI were randomly allocated to two groups. First group received 1mcg/kg of dexmedetomidine in 10 minutes and then infusion of 0.5 mcg/kg/h and second group received 2 mcg/kg fentanyl and then 1 mg midazolam. Hemodynamic variables, O2 saturation (SpO2) were evaluated before and after sedation and after intubation. Ramsey sedation scale (RSS) and patient’s tolerance were evaluated during bronchoscopy and intubation.
Results: Lower heart rate after intubation (p=0.008) and higher SpO2 before sedation (p<0.001) and after intubation (p=0.02) were observed in dexmedetomidine group compared to fentanyl group. The need for propofol for further sedation was comparable between groups (11.5% vs. 7.7%, respectively; p=0.63). Both groups had comparable RSS and tolerance during intubation.
Conclusion: Dexmedetomidine compared to fentanyl and midazolam had comparable sedation with better hemodynamic stability and O2 saturation during AFOI.
Transversus Abdominis Plane Block versus Quadratus Lumborum Block for Postoperative Pain in Abdominal Surgery: A Systematic Review and Meta-analysis
Background: Regional anaesthesia for the prevention and minimization of postoperative pain aims to decrease postoperative pain, opioid consumption and patient controlled analgesia (PCA) requirements. Quadratus Lumborum (QL) blockade and Transversus Abdominis Plane (TAP) blockade are two options for regional anaesthesia following abdominal surgery. The aim of this systematic review was to compare the efficacy of QL versus TAP blockade for management of postoperative pain in abdominal surgery.
Methods: A systematic review of 5 databases (Pubmed, Web of Science, SCOPUS, Medline and CINAHL) was performed. Studies comparing QL block to TAP block for postoperative pain management in abdominal surgery were included. The primary outcome was pain postoperatively. Secondary outcomes included time to rescue analgesia, adverse effects and morphine consumption.
Results: Four studies with a total of 188 patients were included in the final review. A significant reduction in postoperative pain was identified with QL blockade by -0.42 (95%CI= -0.67 to -0.17; I2= 94%; p=0.001). Two high quality studies showed a significant reduction in 24-hour morphine consumption when utilising QL blocks (13.63 mg; 95%CI= 1.48 to 25.78 mg; I2= 98%; p=0.03). However, this review identified no significant difference in time to breakthrough analgesia of 459.69 minutes with QL block (95%CI= -85.33 to 1004.71; I2= 100%; p=0.10). The incidence of adverse effects was similar between the two blocks.
Conclusion: QL blockade leads to a significant reduction in 24-hour morphine consumption and postoperative pain scores, with no increase in adverse event rates. Therefore, QL blockade is likely a preferable regional analgesic technique to TAP blockade, but further large randomised controlled trials are required to confirm these findings.
Background: The objective of this study is to review the literature about the muscle relaxants in anesthetic practice.
Methods: In this review, our search includes, the studies performed and applied between 2000 and 2016. Therefore, for review of muscle relaxants in anesthesia practice in major surgeries, we referred to Google scholar, UpToDate, science direct, Ovid MEDLINE, Springer, free journals and the references of reviewed articles in the English language.
Results: Neuromuscular blocking agents are a chore and essential part of balanced anesthesia. These are used to facilitate endotracheal intubation and provide skeletal muscle relaxation during surgery. The main disadvantage, i.e. residual paralysis, can be treated or prevented by reversing of such a block.
Conclusion: The muscle relaxant plays an important role in adequate muscle relaxation, which allows efficient and safe surgery, requiring automated ventilatory control.
Apert syndrome is a premature fusion of certain skull bones. This early fusion prevents the skull growing normally and affects the shape of the head and face. In addition a varied number of fingers and toes are adhered together. Considering the probability of difficult airway is very important in these patients. Our patient was referred to operating room for syndactyly separation in his lower extremities fingers.