Vimi Rewari

Prolonged steep Trendelenburg position: risk of postoperative upper airway obstruction

Robot-assisted laparoscopic radical prostatectomy (RALRP) is the procedure of choice for the surgical treatment of prostatic cancer. Following induction of anesthesia, the patient is placed in a steep Trendelenburg position (40 – 45 ) in combination with a CO2 pneumoperitoneum. The steep Trendelenburg position is required for an optimal surgical exposure and to utilize the technical advantages of the robot. Besides the physiological effect of this position on the cardiovascular, respiratory and central nervous system, complications such as brachial plexus injuries, corneal abrasions and ischemic optic neuropathy have also been reported [1]. In our experience with RALRP over the last 8 years, upper airway obstruction in the postoperative period is another complication of RALRP which has not been widely reported. Some patients develop an obstructed breathing pattern after extubation associated with agitation and sometimes desaturation despite an adequate reversal of neuromuscular blockade. This is more common in patients who have had prolonged head-down position of more than 3 h or over-enthusiastic fluid therapy exceeding 3 L. Patients who have a large neck circumference or suffer from chronic obstructive airway disease (COPD) are also more prone to develop a similar obstruction. Although there is a report of laryngeal edema following RALRP [2], none of our patients has developed laryngeal edema. The upper airway obstruction usually resolves either with the insertion of a nasopharyngeal airway or with the application of continuous positive airway pressure. In the postanaesthesia care unit, these patients are then nursed in a head-up position and the symptoms resolve in 1–2 h. It has been reported that, in the 45 Trendelenburg position, central venous pressure increases almost threefold compared with the initial value [3]. The head-down position along with pneumoperitoneum also increases the abdominal pressure, which impedes the venous return from the head and neck. This increase in the capillary hydrostatic pressure leads to interstitial accumulation of fluid in the dependent tissues. This is most apparent in the form of periorbital and conjunctival edema. However, edema also forms in the neck and peripharyngeal tissues, which causes constriction of the upper airway lumen. Chiu et al. [4] showed that displacement of a small amount of fluid (340 ml) from the legs is sufficient to cause a 102 % increase in pharyngeal resistance in healthy, non-obese subjects. The degree of fluid accumulation is often directly proportional to the amount of fluid transfused and the length of the surgery. This theory is also corroborated by the fact that fluid overload in fluid-retension states such as heart and renal failure is responsible for the increased incidence of obstructive sleep apnea in these patients [4]. The effect of dependent edema in the upper airway would logically be exaggerated in obese patients with increased neck circumference who already have a compromised upper airway lumen due to fat deposition. In patients with COPD, it has been postulated that cigarette smoking may affect the upper-airway dilator muscles or that treatment with inhaled corticosteroids may cause local pharyngeal muscle myopathy which could lead to obstructive sleep apnea [5]. Therefore, a small amount of edema formation in the upper airway in these patients would make them V. Rewari (&) R. Ramachandran Department of Anaesthesiology, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110029, India e-mail: vimirewari@gmail.com; vimirewari@hotmail.com

Usefulness of pre-emptive peribulbar block in pediatric vitreoretinal surgery: A prospective study

Background and Objectives Vitreoretinal (VR) surgery with or without scleral buckling is associated with significant postoperative pain and emesis in adults, and recent studies have addressed the effect of retro or peribulbar block on these parameters. VR surgery in children has received little attention regarding the incidence of pain and emesis, and the role of regional anesthesia in modifying these parameters. In this study, we compared peribulbar block with conventional opioid analgesia in children undergoing VR surgery. Methods In a prospective, randomized, single-blind study, 85 children (ages 6 to 13 years) were allocated to receive peribulbar block (n = 42) or intravenous meperidine 1 mg/kg (n = 43) after induction of general anesthesia. Parameters compared were: intraoperative incidence of oculocardiac reflex and requirement for additional analgesic; postoperative pain intensity; incidence of postoperative emesis; time to first analgesic, total number of postoperative analgesic supplements; and parental assessment of the child’s postoperative comfort at 24 hours. Results The incidence of intraoperative oculocardiac reflex was significantly less in the peribulbar group (P = .0001). Significantly more children receiving peribulbar block were pain free on awakening (P = .0004) and throughout the postoperative period. The number of children requiring opioid was significantly lower with peribulbar block (P = .008), and a significant number of children did not vomit throughout the postoperative period (P = .001). Conclusions Peribulbar block appears to be a safe and clinically superior alternative to intravenous opioid for pediatric VR surgery. Reg Anesth Pain Med 2003;28:43-47.

Aprepitant for postoperative nausea and vomiting: a systematic review and meta-analysis

Postoperative nausea and vomiting (PONV) is an important clinical problem. Aprepitant is a relatively new agent for this condition which may be superior to other treatment. A systematic review was performed after searching a number of medical databases for controlled trials comparing aprepitant with conventional antiemetics published up to 25 April 2015 using the following keywords: ‘Aprepitant for PONV’, ‘Aprepitant versus 5-HT3 antagonists’ and ‘NK-1 versus 5-HT3 for PONV’. The primary outcome for the pooled analysis was efficacy of aprepitant in preventing vomiting on postoperative day (POD) 1 and 2. 172 potentially relevant papers were identified of which 23 had suitable data. For the primary outcome, 14 papers had relevant data. On POD1, 227/2341 patients (9.7%) patients randomised to aprepitant had a vomiting episode compared with 496/2267 (21.9%) controls. On POD2, the rate of vomiting among patients receiving aprepitant was 6.8% compared with 12.8% for controls. The OR for vomiting compared with controls was 0.48 (95% CI 0.34 to 0.67) on POD1 and 0.54 (95% CI 0.40 to 0.72) on POD2. Aprepitant also demonstrated a better profile with a lower need for rescue antiemetic and a higher complete response. Efficacy for vomiting prevention was demonstrated for 40 mg, 80 mg and 125 mg without major adverse effects. For vomiting comparison there was significant unexplainable heterogeneity (67.9% and 71.5% for POD1 and POD2, respectively). We conclude that (1) aprepitant reduces the incidence of vomiting on both POD1 and POD2, but there is an unexplained heterogeneity which lowers the strength of the evidence; (2) complete freedom from PONV on POD1 is highest for aprepitant with minimum need for rescue; and (3) oral aprepitant (80 mg) provides an effective and safe sustained antivomiting effect.

Evaluation of the SCOTI device for confirming blind nasal intubation

The sonomatic confirmation of tracheal intubation (SCOTI) is a new device used to confirm the correct placement of tracheal tubes. It utilises a sonic technique for recognition of a resonating frequency for detection of tracheal intubation. We compared its predictive value with that of the clinical auscultatory method and a capnograph to confirm 132 blind nasal intubations using three different tracheal tubes [red rubber (n = 82), polyvinyl chloride (n = 33) and RAE preformed nasal (n = 17)]. SCOTI correctly identified 70.8% of intubations and chest auscultation did so 99.2% of times. All results were confirmed using a capnograph. The SCOTI device gave a false‐negative value in 37 patients (28%) and a false‐positive result in two patients (1.5%). The response time for confirming intubations was 2.5 (1.5) s for the SCOTI, 4.1 (1.1) s for a capnograph and 40 (9.4) s for the auscultatory method. The erroneous results shown by the SCOTI device were highest when polyvinyl chloride tubes with a Murphys eye were used for intubation. This study shows that this device is not very useful for ascertaining the correct placement of tracheal tubes after blind nasal intubation.

Analgesic efficacy of ultrasound guided transversus abdominis plane block versus local anesthetic infiltration in adult patients undergoing single incision laparoscopic cholecystectomy: A randomized controlled trial

Background: Transversus abdominis plane (TAP) block has been used to provide intra- and post-operative analgesia with single incision laparoscopic (SIL) bariatric and gynecological surgery with mixed results. Its efficacy in providing analgesia for SIL cholecystectomy (SILC) via the same approach remains unexplored. Aims: The primary objective of our study was to compare the efficacy of bilateral TAP block with local anesthetic infiltration for perioperative analgesia in patients undergoing SILC. Settings and Design: This was a prospective, randomized, controlled, double-blinded trial performed in a tertiary care hospital. Materials and Methods: Forty-two patients undergoing SILC were randomized to receive either ultrasound-guided (USG) bilateral mid-axillary TAP blocks with 0.375% ropivacaine or local anesthetic infiltration of the port site. The primary outcome measure was the requirement of morphine in the first 24 h postoperatively. Statistical Analysis: The data were analyzed using t-test, Mann–Whitney test or Chi-square test. Results: The 24 h morphine requirement (mean ± standard deviation) was 34.57 ± 14.64 mg in TAP group and 32.76 ± 14.34 mg in local infiltration group (P = 0.688). The number of patients requiring intraoperative supplemental fentanyl in TAP group was 8 and in local infiltration group was 16 (P = 0.028). The visual analog scale scores at rest and on coughing were significantly higher in the local infiltration group in the immediate postoperative period (P = 0.034 and P= 0.007, respectively). Conclusion: USG bilateral TAP blocks were not effective in decreasing 24 h morphine requirement as compared to local anesthetic infiltration in patients undergoing SILC although it provided some analgesic benefit intraoperatively and in the initial 4 h postoperatively. Hence, the benefits of TAP blocks are not worth the effort and time spent for administering them for this surgery.

Successful use of C-Mac video laryngoscope in a child with large parapharyngeal mass.

An eleven‐year‐old child presented with a history of gradually increasing left side neck swelling and snoring for the last 6 years. He was initially scheduled for biopsy and on a second occasion for transcervical excision of left parapharyngeal mass under general anesthesia. Examination showed a left lateral pharyngeal and tonsillar mass compressing the oropharyngeal airway. CT neck showed a soft tissue mass (7 × 6 × 9 cm) in the left retropharyngeal space causing a bulge in the oropharynx with lateral deviation of carotid artery and internal jugular vein. During the first anesthesia for the biopsy, oral fiberoptic bronchoscopy (FOB), direct laryngoscopy, and Glidescope video laryngoscopy failed to visualize the glottis and epiglottis. After repeated attempts, intubation was possible with direct laryngoscopic‐guided oral FOB. Fifteen days later, for the definitive surgery, the glottis was visualized at the first attempt using a C‐Mac video laryngoscope and endotracheal intubation was successful at the first attempt after laryngeal manipulation. We discuss the potential causes of failure of intubation with the other airway devices in this child.

Morphine versus Nalbuphine for Open Gynaecological Surgery: A Randomized Controlled Double Blinded Trial.

Introduction. Pain is the commonest morbidity after open surgical procedures. The most effective treatment of postoperative pain is opioid therapy. Morphine, the commonly used opioid, is associated with many side effects including respiratory depression, sedation, postoperative nausea vomiting, and pruritus. Nalbuphine, on the other hand, is known to cause less respiratory depression. Thus this study was undertaken to compare the intraoperative and postoperative analgesic efficacy and side effect profile of the two drugs. Methodology. 60 patients undergoing open gynaecological surgery were randomized to receive either morphine (Group M) or nalbuphine (Group N) in the intraoperative and postoperative period. Intraoperative analgesic efficacy (measured by need for rescue analgesics), postoperative pain by visual analogue scale, and side effects like postoperative nausea, vomiting, sedation, respiratory depression, and pruritus were compared in both groups. Intraoperative and postoperative heart rate and blood pressure were also compared between the groups. Results. Need for intraoperative analgesia was significantly more in Group N (P = 0.023). Postoperative VAS scores were significantly different between the groups at various time points; however, none of the patients required any rescue analgesia. The incidence of various side effects was not significantly different between the groups. The haemodynamic profile of patients was comparable between the groups in both intraoperative and postoperative period. Conclusion. Nalbuphine provides less effective intraoperative analgesia than morphine in patients undergoing open gynaecological surgery under general anaesthesia. Both drugs, however, provided similar postoperative analgesia and had similar haemodynamic and side effect profile.

A retrospective analysis of determinants of self-extubation in a tertiary care intensive care unit

Background: Self-extubation is a common event in intensive care units (ICUs) world-wide. The most common factor attributed in various studies is lack of optimal sedation. However, the factors that lead to this inadequacy of sedation are not analyzed. Aims: The present study aimed to evaluate the determinants of factors leading to self-extubation in our ICU. Relation of patient profile, nature of sedation and any diurnal variation in extubation frequency was analyzed Materials and Methods Retrospective explorative analysis was carried out for patients admitted to ICU from January 2011 to January 2012. Information from medical records for the above parameters was extracted and descriptive statistics was used for assessing the outcomes. Results: In the present study, there was a higher incidence of self-extubation in ventilated ICU patients during the changeover periods of the ICU staff. There was no relation of frequency of self-extubation with the medications used for sedation once the sedation was titrated to a common endpoint. A higher incidence of self-extubation was seen in the surgical and younger age group of patients. Conclusions: It is recommended that the duty shift finishing time of ICU staff (medical and paramedical) staff should be staggered and should have minimal overlap to prevent self-extubation. A continuous reassessment of level of sedation of patients independent of the type sedative medication should be carried out.

Is perioperative administration of 5% dextrose effective in reducing the incidence of PONV in laparoscopic cholecystectomy?: A randomized control trial

STUDY OBJECTIVE To compare the incidence of postoperative nausea and vomiting (PONV) during perioperative administration of 5% dextrose and normal saline in laparoscopic cholecystectomy. DESIGN Prospective, randomized, double-blind trial. SETTING Operating rooms in a tertiary care hospital of Northern India. PATIENTS One hundred patients with American Society of Anesthesiologists status I to II undergoing laparoscopic cholecystectomy were enrolled in this study. INTERVENTIONS Patients were randomized into two groups [normal saline (NS) group and 5% dextrose (D) group]. Both the groups received Ringer acetate (Sterofundin ISO) intravenously as a maintenance fluid during intraoperative period. Besides this, patients of group NS received 250ml of 0.9% normal saline and patients of group D received 5% dextrose @ 100ml/h started at the time when gall bladder was taken out. It was continued in the postoperative period with the same rate till it gets finished. MEASUREMENTS Incidence of PONV, Apfel score, intraoperative opioids used and consumption of rescue antiemetics. MAIN RESULTS Demographic data was statistically similar. Out of total 100 patients, 47 patients (47%) had PONV. In group D, 14 patients (28%) had PONV while in group NS, 33 patients (66%) had PONV within 24h of surgery (p value 0.001). The incidence of PONV was reduced by 38% in group D which is significantly lower when compared with that of group NS (p value 0.001). The consumption of single dose of rescue antiemetics in group D was also reduced by 26% when compared to that of group NS (p value 0.002). CONCLUSIONS Perioperative administration of 5% dextrose in patients undergoing laparoscopic surgery can reduce PONV significantly and even if PONV occurs, the quantity of rescue antiemetics to combat PONV is also reduced significantly.

Anaesthetic management of patients with peripartum cardiomyopathy

Peripartum cardiomyopathy (PPCM) is a disease affecting the parturient during late pregnancy or immediately after delivery. This unique disorder not just endangers the life of mother and progeny but is also a financial burden to the health system due to its potential to cause prolonged and persistent cardiac function insufficiency in the mother. The hallmark of the disease is onset of decreased cardiac ejection fraction either in the late pregnancy or early puerperium. Over the last few decades, the disease has been extensively researched and investigated to formulate diagnostic guidelines and therapeutic approaches. Many theories regarding its pathophysiology have also been proposed. The clinical presentation and the basic and intensive interventional strategies of the disease are more or less similar to that of dilated cardiomyopathy due to any other cause; however, at all points of time the pregnant or lactating state of mother and the subsequent effect of the medication and therapeutic interventions on the fetus or neonate needs to be considered. Apart from intensive care management, these patients may also require anaesthetic intervention for management of painless labor and/or either vaginal or operative delivery. Favorable maternal and fetal outcome require that the basic hemodynamic goals be always kept in mind while choosing the techniques and drugs to provide anaesthesia to the patients with PPCM. Literature search of the anaesthetic management of patients with diagnosis of PPCM undergoing operative delivery reveals both general and regional anaesthesia being used with comparable outcomes.