Rajeev Subramanyam

Use of Manometry for Laryngeal Mask Airway Reduces Postoperative Pharyngolaryngeal Adverse Events: A Prospective, Randomized Trial

Background:Adverse events such as pharyngolaryngeal complications are indicators of quality patient care. Use of manometry to limit the laryngeal mask airway (LMA) intracuff pressure is not currently a routine practice. This double-blind randomized trial compared pharyngolaryngeal complications in patients managed with manometers to limit the LMA intracuff pressure (<44 mmHg) with patients under routine care. Method:Two hundred consenting patients who underwent ambulatory surgery were randomly allocated to pressure-limiting and routine care groups. Anesthesia was induced with propofol and fentanyl, and maintained with desflurane in air–oxygen. An LMA was inserted, and the cuff was inflated as per usual practice. The patients breathed spontaneously. Research assistants measured the LMA intracuff pressure. In the pressure-limiting group, LMA intracuff pressure was adjusted to less than 44 mmHg. No intervention was performed in the routine care group. Sore throat, dysphonia, and dysphagia were assessed at 1, 2, and 24 h postoperatively. Composite pharyngolaryngeal complications were compared using chi-square test. Results:Baseline demographic data were comparable between groups. Mean LMA intracuff pressure was less in the pressure-limiting group versus the routine care group (40 ± 6 vs. 114 ± 57 mmHg, P < 0.001). The incidence of composite pharyngolaryngeal complications was significantly lower in the pressure-limiting group versus the routine care group (13.4 vs. 45.6%, P < 0.001), with a relative risk reduction of 70.6%, and a number needed to treat of three (95% CI 2.2–7.5). Conclusion:Reduction of LMA intracuff pressure to less than 44 mmHg lowers the incidence of postoperative pharyngolaryngeal complications. The LMA cuff pressures should be measured routinely using manometry, and deflating the intracuff pressure to less than 44 mmHg should be recommended as anesthetic best practice.

Anesthesia‐ and opioids‐related malpractice claims following tonsillectomy in USA: LexisNexis claims database 1984–2012

Although commonly performed, tonsillectomy is not necessarily a low‐risk procedure for litigation. We have reviewed malpractice claims involving fatal and nonfatal injuries following tonsillectomy with an emphasis on anesthesia‐ and opioid‐related claims and their characteristics.

Cost‐effectiveness of intravenous acetaminophen for pediatric tonsillectomy

The primary outcome of this study was to examine the cost‐effectiveness of the intraoperative combination of intravenous (IV) acetaminophen and IV opioids, versus IV opioids alone, as a part of an inhalational anesthetic technique for tonsillectomy in children.

Comparison of the combination of dexmedetomidine and ketamine to propofol or propofol/sevoflurane for drug-induced sleep endoscopy in children

Examination of dynamic airway collapse in patients with obstructive sleep apnea (OSA) during drug‐induced sleep endoscopy (DISE) can help identify the anatomic causes of airway obstruction. We hypothesized that a combination of dexmedetomidine and ketamine (Group DK) would result in fewer oxygen desaturations and a higher successful completion rate during DISE in children with OSA when compared to propofol (Group P) or sevoflurane/propofol (Group SP).

Systematic review of risk factors for surgical site infection in pediatric scoliosis surgery

BACKGROUND CONTEXT Risk factors for surgical site infection (SSI) in children derived from the studies in the adult population are potentially misleading because of differences in pathophysiology and management. PURPOSE This systematic review addresses the key question: What are the risk factors for SSI in pediatric patients undergoing scoliosis surgery? STUDY DESIGN This is a qualitative systematic literature review. PATIENT SAMPLE Retrospective and observational trials of children undergoing scoliosis surgery reported on the occurrence of risk factors for SSI and the occurrence of SSI. METHODS Pubmed (Medline), Ovid Evidence-Based Medicine Reviews (EBMR), Scopus, and Cumulative Index to Nursing and Allied Health (CINAHL) were searched electronically for relevant articles in all the languages between January 1, 1991 and August 27, 2012, and cross-references were checked. Two independent reviewers identified articles and appraised quality with the Agency for Healthcare Research and Quality (AHRQ) criteria based on a weighted scoring of 0 to 100. RESULTS Our search identified 135 abstracts and 14 studies meeting the inclusion criteria. The AHRQ grading showed that five articles were high quality with a score of greater than 67, and five articles were moderate quality with a score between 50 and 67. The percent agreement between the two independent reviewers was 84%, and kappa agreement score was 0.91 (95% confidence interval [CI]: 0.78-1.03). There were 76 risk factors identified, of which 22 factors were reported in more than one study. Odds ratios and 95% CIs were reported inconsistently. Pooled p analysis of high- and moderate-quality articles identified five risk factors predictive of SSI: inappropriate antibiotic use (p=.001), neuromuscular scoliosis (p=.014), instrumentation (p=.023), increased hospital stay days (p=.003), and residual postoperative curve (p=.003). CONCLUSIONS The systematic review identified inappropriate antibiotic use, neuromuscular scoliosis, instrumentation, increased hospital stay days, and residual postoperative curve as risk factors for SSI after pediatric scoliosis surgery.

To Pretreat or Not to Pretreat: Prophylactic Anticholinergic Administration Before Dexmedetomidine in Pediatric Imaging.

BACKGROUND:Dexmedetomidine (Dex) appears to be very effective as a sole sedative for pediatric imaging when used at high doses, but at an increased risk of transient hypertension, hypotension, and bradycardia. There are no clinical evidence/guidelines to guide anesthesia providers as to whether patients should be pretreated with an anticholinergic. The aim of this study was to demonstrate the changes in hemodynamic parameters after Dex sedation attributed to receiving or not receiving an anticholinergic pretreatment and compare for any differences or similarities. A subgroups analysis was performed in children with Down syndrome (DS). METHODS:In this retrospective descriptive study, we reviewed the records of 163 children receiving Dex anesthesia during MRI studies. Data analyzed included demographics, history of DS, and hemodynamics (heart rate [HR], systolic blood pressure [SBP], and diastolic blood pressure [DBP]) following Dex loading and infusion and the administration of an anticholinergic (atropine or glycopyrrolate). RESULTS:The mean age was 94.5 months, and 52 (32%) patients had DS. The generalized linear mixed-effects regression model showed a significant reduction in HR and SBP in all patients when no anticholinergic was administered compared with when it was administered. There was no significant change with DBP. During the scan period, the HR of the no-anticholinergic group decreased 26.6%, whereas that of the anticholinergic group decreased by only 16.7% from baseline (P < 0.01). The maximal SBP increased by a significantly greater percentage, compared with baseline, in the anticholinergic group in comparison with the no-anticholinergic group (20.2% vs 10.4%, respectively; P = 0.02). In the DS group, the difference in the maximal SBP change during the scan period was exaggerated, with a percentage increase that was 36 times larger in the anticholinergic group compared with the no-anticholinergic group (22% vs 0.6%, respectively; P< 0.01). CONCLUSIONS:Administration of a prophylactic anticholinergic with Dex shows no advantage other than a transient clinically insignificant increase in HR and SBP, and it may precipitate transient exaggerated SBP in more patients compared with not using a prophylactic anticholinergic.

Intrathecal clonidine decreases propofol sedation requirements during spinal anesthesia in infants

Background:  Propofol is a popular agent for providing procedural sedation in pediatric population during lumbar puncture and spinal anesthesia. Adjuvants like clonidine and fentanyl are administered intrathecally to prolong the duration of spinal anesthesia and to provide postoperative analgesia. We studied the propofol requirement after intrathecal administration of clonidine or fentanyl in infants undergoing lower abdominal surgeries.

Perioperative Respiratory Adverse Events in Pediatric Ambulatory Anesthesia: Development and Validation of a Risk Prediction Tool.

BACKGROUND:Perioperative respiratory adverse events (PRAEs) are the most common cause of serious adverse events in children receiving anesthesia. Our primary aim of this study was to develop and validate a risk prediction tool for the occurrence of PRAE from the onset of anesthesia induction until discharge from the postanesthesia care unit in children younger than 18 years undergoing elective ambulatory anesthesia for surgery and radiology. The incidence of PRAE was studied. METHODS:We analyzed data from 19,059 patients from our department’s quality improvement database. The predictor variables were age, sex, ASA physical status, morbid obesity, preexisting pulmonary disorder, preexisting neurologic disorder, and location of ambulatory anesthesia (surgery or radiology). Composite PRAE was defined as the presence of any 1 of the following events: intraoperative bronchospasm, intraoperative laryngospasm, postoperative apnea, postoperative laryngospasm, postoperative bronchospasm, or postoperative prolonged oxygen requirement. Development and validation of the risk prediction tool for PRAE were performed using a split sampling technique to split the database into 2 independent cohorts based on the year when the patient received ambulatory anesthesia for surgery and radiology using logistic regression. A risk score was developed based on the regression coefficients from the validation tool. The performance of the risk prediction tool was assessed by using tests of discrimination and calibration. RESULTS:The overall incidence of composite PRAE was 2.8%. The derivation cohort included 8904 patients, and the validation cohort included 10,155 patients. The risk of PRAE was 3.9% in the development cohort and 1.8% in the validation cohort. Age ⩽ 3 years (versus >3 years), ASA physical status II or III (versus ASA physical status I), morbid obesity, preexisting pulmonary disorder, and surgery (versus radiology) significantly predicted the occurrence of PRAE in a multivariable logistic regression model. A risk score in the range of 0 to 3 was assigned to each significant variable in the logistic regression model, and final score for all risk factors ranged from 0 to 11. A cutoff score of 4 was derived from a receiver operating characteristic curve to determine the high-risk category. The model C-statistic and the corresponding SE for the derivation and validation cohort was 0.64 ± 0.01 and 0.63 ± 0.02, respectively. Sensitivity and SE of the risk prediction tool to identify children at risk for PRAE was 77.6 ± 0.02 in the derivation cohort and 76.2 ± 0.03 in the validation cohort. CONCLUSIONS:The risk tool developed and validated from our study cohort identified 5 risk factors: age ⩽ 3 years (versus >3 years), ASA physical status II and III (versus ASA physical status I), morbid obesity, preexisting pulmonary disorder, and surgery (versus radiology) for PRAE. This tool can be used to provide an individual risk score for each patient to predict the risk of PRAE in the preoperative period.

Morfologia das vias aéreas superiores em pacientes com síndrome de Down sob sedação com dexmedetomidina.

BACKGROUND AND OBJECTIVES Children with Down Syndrome are vulnerable to significant upper airway obstruction due to relative macroglossia and dynamic airway collapse. The objective of this study was to compare the upper airway dimensions of children with Down Syndrome and obstructive sleep apnea with normal airway under dexmedetomidine sedation. METHODS IRB approval was obtained. In this retrospective study, clinically indicated dynamic sagittal midline magnetic resonance images of the upper airway were obtained under low (1mcg/kg/h) and high (3mcg/kg/h) dose dexmedetomidine. Airway anteroposterior diameters and sectional areas were measured as minimum and maximum dimensions by two independent observers at soft palate (nasopharyngeal airway) and at base of the tongue (retroglossal airway). RESULTS AND CONCLUSIONS Minimum anteroposterior diameter and minimum sectional area at nasopharynx and retroglossal airway were significantly reduced in Down Syndrome compared to normal airway at both low and high dose dexmedetomidine. However, there were no significant differences between low and high dose dexmedetomidine in both Down Syndrome and normal airway. The mean apnea hypopnea index in Down Syndrome was 16±11. Under dexmedetomidine sedation, children with Down Syndrome and obstructive sleep apnea when compared to normal airway children show significant reductions in airway dimensions most pronounced at the narrowest points in the nasopharyngeal and retroglossal airways.

Upper airway morphology in Down Syndrome patients under dexmedetomidine sedation

BACKGROUND AND OBJECTIVES Children with Down Syndrome are vulnerable to significant upper airway obstruction due to relative macroglossia and dynamic airway collapse. The objective of this study was to compare the upper airway dimensions of children with Down Syndrome and obstructive sleep apnea with normal airway under dexmedetomidine sedation. METHODS IRB approval was obtained. In this retrospective study, clinically indicated dynamic sagittal midline magnetic resonance images of the upper airway were obtained under low (1mcg/kg/h) and high (3mcg/kg/h) dose dexmedetomidine. Airway anteroposterior diameters and sectional areas were measured as minimum and maximum dimensions by two independent observers at soft palate (nasopharyngeal airway) and at base of the tongue (retroglossal airway). RESULTS AND CONCLUSIONS Minimum anteroposterior diameter and minimum sectional area at nasopharynx and retroglossal airway were significantly reduced in Down Syndrome compared to normal airway at both low and high dose dexmedetomidine. However, there were no significant differences between low and high dose dexmedetomidine in both Down Syndrome and normal airway. The mean apnea hypopnea index in Down Syndrome was 16±11. Under dexmedetomidine sedation, children with Down Syndrome and obstructive sleep apnea when compared to normal airway children show significant reductions in airway dimensions most pronounced at the narrowest points in the nasopharyngeal and retroglossal airways.