The intensive care unit (ICU) environment is often perceived to be hostile and frightening by patients due to unfamiliar surroundings coupled with presence of numerous personnel, monitors and other equipments as well as a loss of perception of time. Mechanical ventilation and multiple painful procedures that often need to be carried out in these critically ill patients add to their overall anxiety. Sedation is therefore required not only to allay the stress and anxiety, but also to allow for mechanical ventilation and other invasive therapeutic and diagnostic procedures to be performed. The conventional intravenous sedative agents used in ICUs suffer from problems of over sedation, tachyphylaxis, drug accumulation, organ specific elimination and often lead to patient agitation on withdrawal. All this tend to prolong the ventilatory as well as ICU and hospital discharge time, which increase the risk for infection and add to the overall increase in morbidity, mortality and hospital costs. In 2005, the anaesthetic conserving device (AnaConDa^® ) was marketed for ICU sedation with volatile anaesthetic agents. A number of trials have shown the effectiveness of using volatile anaesthetic agents for ICU sedation with the AnaConDa device. Compared with intravenous sedatives, use of volatile anaesthetic agents have resulted in shorter wake up and extubation time, lesser duration of mechanical ventilation and faster discharge from hospitals. This review shall focus on the benefits, technical pre-requisites and status of sedation with volatile anaesthetic agents in ICUs with the AnaConDa^® device.

There was an era when bark of mandrake plant, boiled in wine was used to administer anesthesia. Ether, after reigning the kingdom of anaesthesiology for more than a century, came to be superseded by newer and newer agents. Anaesthesiology has witnessed tremendous developments since infancy. The introduction of advanced airway adjuncts, labour analgesia, patient controlled analgesia, fibreoptics, Bispectral Index monitors, workstations, simulators and robotic surgeries are only to name a further few. Anaesthesia for robotic surgery received much impetus and is still a dream to come true in many countries. But then, the rapid spin in technology and fast sophistication of medical field has even surpassed this. The next event to venture is entry of robots into human body made possible by a culmination of intricate medicine and fine technology that is Nanotechnology. This article briefly introduces the field of nanotechnology in relation to its potential benefits to the field of anaesthesiology. As with any new tecnique or application, nanotechnology as applied to anaesthesiology has tremendous potential for research and exploration. This article therefore orients the reader's mind towards the immense potential and benefits that can be tapped by carrying out further studies and experimentations.The literature was searched using databases, peer reviewed journals and books for over a period of one year (till December 2011). The search was carried out using keywords as nanotechnology, robotics, anesthesiology etc. Initially a master database was formed including human as well as animal studies. Later on the broad topic area was narrowed down to developments in nanotechnology as applied to anesthesiology. Further filtering of search results were done based on selection of researches and developments relating to local, regional and general anesthesia as well as critical care and pain and palliative care.

Background: It is difficult to visualise the larynx using conventional laryngoscopy in the presence of cervical spine immobilisation. Airtraq^® provides for easy and successful intubation in the neutral neck position. Objective: To evaluate the effectiveness of Airtraq in comparison with the Mc Coy laryngoscope, when performing tracheal intubation in patients with neck immobilisation using hard cervical collar and manual in-line axial cervical spine stabilisation. Methods: A randomised, cross-over, open-labelled study was undertaken in 60 ASA I and II patients aged between 20 and 50 years, belonging to either gender, scheduled to undergo elective surgical procedures. Following induction and adequate muscle relaxation, they were intubated using either of the techniques first, followed by the other. Intubation time and Intubation Difficulty Score (IDS) were noted using Mc Coy laryngoscope and Airtraq. The anaesthesiologist was asked to grade the ease of intubation on a Visual Analogue Scale (VAS) of 1-10. Chi-square test was used for comparison of categorical data between the groups and paired sample t-test for comparison of continuous data. IDS score and VAS were compared using Wilcoxon Signed ranked test. Results: The mean intubation time was 33.27 sec (13.25) for laryngoscopy and 28.95 sec (18.53) for Airtraq (P=0.32). The median IDS values were 4 (interquartile range (IQR) 1-6) and 0 (IQR 0-1) for laryngoscopy and Airtraq, respectively (P=0.007). The median Cormack Lehane glottic view grade was 3 (IQR 2-4) and 1 (IQR 1-1) for laryngoscopy and Airtraq, respectively (P=0.003). The ease of intubation on VAS was graded as 4 (IQR 3-5) for laryngoscopy and 2 (IQR 2-2) for Airtraq (P=0.033). There were two failures to intubate with the Airtraq. Conclusion: Airtraq improves the ease of intubation significantly when compared to Mc Coy blade in patients immobilised with cervical collar and manual in-line stabilisation simulating cervical spine injury.

Background and Context: Beta - blockers have been used for attenuation of stress response, decreasing anaesthetic requirement and augmentation of the effect of opioids during general anaesthesia. Aims and Objectives: The present study aims to evaluate the influence of esmolol on the requirement of an inhalational agent while monitoring the depth of anaesthesia by entropy and also its effect on immediate postoperative pain score. Methods: Fifty American Society of Anaesthesiologists (ASA) I and II patients, between 25 and 65 years of age who underwent lower abdominal surgeries were randomly allocated to two groups: Group E and Group S of 25 patients each. Group E received esmolol infusion while Group S received the same volume of saline infusion. Demographic data, haemodynamics, amount of isoflurane used, end-tidal isoflurane concentration, postoperative pain score and total dose of morphine consumed in immediate postoperative period of 30 min were analyzed by using appropriate statistical tests. Value of P<0.05 was considered significant and P<0.001 as highly significant. Results: The two groups were comparable with respect to age, weight, ASA physical status, duration of surgery and amount of isoflurane used during anaesthesia. Assessment of postoperative pain was assessed by Visual Analogue Scale (VAS) which showed significant difference at 30 min. The total dose of morphine consumption was significantly less (P<0.05) in Group E for relief of postoperative pain. Conclusions: We conclude that in light of depth of anaesthesia monitor esmolol has no effect on requirement of isoflurane, but it decreases the postoperative pain as well as postoperative requirement of morphine without increasing the risk of awareness.

Background: Dexmedetomidine, an α2 agonist, when used as an adjuvant in general anaesthesia attenuates stress response to various noxious stimuli, maintains perioperative haemodynamic stability and provides sedation without significant respiratory depression postoperatively. Methods: Sixty patients were randomly divided into two groups of 30 each. In group A, fentanyl 2 μg/kg and in group B dexmedetomidine were given intravenously as loading dose of 1 μg/kg over 10 min prior to induction. After induction with thiopentone, in group B, dexmedetomidine was given as infusion at a dose of 0.2-0.8 μg/kg. Sevoflurane was used as inhalation agent in both groups. Haemodynamic variables and entropy (response entropy and state entropy) were recorded continuously. Postoperative sedation and recovery were assessed by sedation score and modified Aldrete's score, respectively. Results: Dexmedetomidine significantly attenuates stress response at intubation with lesser increase in heart rate (10% vs. 17%), systolic blood pressure (6% vs. 23%) and diastolic blood pressure (7% vs. 20%) as compared to the control group (P<0.05). Intraoperatively, an average of 8% fall in systolic blood pressure and 8.16% fall in diastolic pressure in the test group as compared to 3.6% rise in systolic and 3.3% in diastolic pressure of the control group was observed. Postoperatively, the test group showed significant sedation at 2 h as compared to the control group (P=0.00) and recovery was better in the control group for the first 2 h post extubation. Conclusion: Dexmedetomidine attenuates various stress responses during surgery and maintains the haemodynamic stability when used as an adjuvant in general anaesthesia. Also, the sedative action of dexmedetomidine delays recovery for the first few hours post extubation.

Aims and Objectives: To compare the efficacy of sedation and time taken for extubation using dexmedetomidine and fentanyl sedation in post-operative paediatric cardiac surgical patients. Methods: A prospective randomized double-blind study involving 60 children undergoing open heart surgery was conducted. The patients were divided into two groups, each involving 30 patients. One group received fentanyl at 1 μg/kg/h (Group A) and the other received dexmedetomidine at 0.5 μg/kg/h (Group B) for post-operative sedation with intermittent rescue fentanyl 0.5 μg/kg bolus in either group as per requirement during suctioning. The efficacy of sedation was assessed using the Ramsay sedation score, paediatric intensive care unit sedation score and the tracheal suction score. The time taken for extubation from the stoppage of infusion was noted. Results: Haemodynamic parameters between the two groups were comparable. All sedation scores were comparable in the fentanyl and dexmedetomidine groups. Average time (in minutes) required for extubation was 131.0 (±51.06 SD) in the dexmedetomidine group compared with 373.0 (±121.4 SD) in the fentanyl group. The difference in mean time for extubation was statistically significant. Conclusions: Dexmedetomidine facilitates adequate sedation for mechanical ventilation and also early extubation as compared with fentanyl.

Background: Visual analog scales (VAS) and numeric analog scales (NAS) are used to assess post-operative pain, but few studies indicate their usefulness in rural illiterate population in India. Aims: This study was designed to 1) Compare the impact of literacy on the ability to indicate pain rating on VAS and NAS in post-operative rural patients. 2) Assess the level of agreement between the pain scales. Setting and Design: Cross sectional, hospital based study. Methods: Informed consent was obtained from patients prior to undergoing surgical procedures in a teaching hospital. Post surgery, patients who were conscious and coherent, were asked to rate pain on both VAS and NAS. The pain ratings were obtained within 24 hours of surgery and within 5 minutes of each other. Statistical Methods: Percentages, chi square test, regression analysis. Results: A total of 105 patients participated in the study. 43 (41%) of the sample was illiterate. 82 (78.1%) were able to rate pain on VAS while 81 (77.1%) were able to rate pain on NAS. There was no significant association between pain ratings and type of surgery, duration of surgery and nature of anaesthesia. In multivariate analysis, age, sex and literacy had no significant association with the ability to rate pain on VAS (P value 0.652, 0.967, 0.328 respectively). Similarly, no significant association was obtained between age, sex and literacy and ability to rate pain on NAS (P value 0.713, 0.405, 0.875 respectively). Correlation coefficient between the scales was 0.693. Conclusion: VAS and NAS can be used interchangeably in Indian rural population as post-operative pain assessment tools irrespective of literacy status.

Background: Ventilator-associated pneumonia (VAP) is a common complication of ventilatory support for patients with acute respiratory failure and is associated with increased morbidity and mortality. Aim of the Study: The present study was undertaken to do quantitative cultures of aerobic bacteria, perform the antibiotic susceptibility testing from the endotracheal aspirates and clinical outcome of the clinically suspected patients of VAP. Methods: A prospective study was performed over a period of one year in a tertiary care hospital, enrolling patients on mechanical ventilation (MV) for ≥48 hr. Endotracheal aspirates (ETA) were collected from patients with suspected VAP, and direct gram's stain criteria was used to accept the sample. Quantitative cultures of ETA were performed with the threshold for microbiological diagnosis of VAP was taken as ≥10 ⁵ colony forming units (cfu)/ml. Results: Out of 53 cases, 2 (3.77%) were polymicrobial. Multidrug resistant bacteria, mainly Acinetobacter baumannii 49.09% (27/55) and Pseudomonas aeruginosa 30.91% (17/55) were the most common pathogens isolated. Metallo-beta lactamases (MBLs) was produced by 47.06% (8/17) of Pseudomonas aeruginosa and 62.96% (17/27) of Acinetobacter baumannii. Conclusion: The bacteriological approach for the management of VAP helps the clinicians in choosing the appropriate antibiotics. This study showed that quantitative cultures of endotracheal aspirate at a cutoff point of 10 ⁵ cfu/ml is one of the alternative to bronchoscopy in the diagnosis of clinically suspected ventilator associated pneumonia.

Background and Aim: Patent blue vital (PBV) dye is used for varied perioperative indications, and has a potential for causing life-threatening allergic reactions. In this retrospective case series study, at a tertiary level neurosciences centre, we analysed the nature, management and outcome of adverse drug reaction to the preoperative use of PBV for marking vertebral level prior to back surgeries. Methods: Patients were identified from the theatre and radiology database. Data were collected from the patients' notes retrieved from the medical records division. Results: Eleven of 1247 (0.88%) patients experienced adverse reactions: 6 (0.48%) patients had minor grade I reactions (urticaria, blue hives, pruritis or generalised rash), 4 (0.32%) had grade II reactions (transient hypotension/bronchospasm/laryngospasm) and grade III reaction (hypotension requiring prolonged vasopressor support) was noted in 1 (0.08%) patient. No mortality was seen. The time of onset (range 10-45 min) frequently coincided with induction of anaesthesia or prone positioning of patient. Seven (63.6%) cases were cancelled or postponed (range 2-63 days). Treatment varied independent of the grade of reaction. Allergy workup (often incomplete) was done for 6 (54%) patients. Conclusion: An awareness of the time of onset and infrequency of life-threatening reactions to patent blue dye may result in better management, less postponement, more complete workup and referral of these events.

One-lung ventilation for a thoracotomy procedure was achieved with the help of a endobronchial blocker in a young girl with limited mouth opening, minimal neck extension, and a distorted tracheo-bronchial anatomy. As the patient would not cooperate for an awake nasotracheal intubation despite adequate preperation, an inhalational anesthetic was used to make the patient unconscious, taking care that spontaneous breathing was maintained. Nasotracheal intubation was done with the help of a fiberoptic bronchoscope. A wire-guided Arndt endobronchial blocker was placed coaxially through the endotracheal tube using a fiberoptic bronchoscope. This case report highlights that in a scenario of both upper and lower airway distortion, a bronchial blocker positioned through a nasotracheal tube under fiberoptic guidance might be the best option when one-lung ventilation is required.

Safety pins are not commonly aspirated objects in infants and form only a small fraction of all the metallic foreign body (FB) which accounts for 4.4% of all foreign bodies found in tracheobronchial tree. Bronchoscopy procedure has various complications, in addition to failure to remove FB due to its impaction, especially with metallic pointed objects ending up in open surgical removal. Infant with inhaled foreign body are always a challenge to anaesthetist. We had one such case of broken safety pin impacted in the wall of right bronchus of an infant with failure to remove on repeated attempts at rigid bronchoscopy.

Fontan procedure is a palliative surgery done for patients born with single ventricle physiology. An understanding of the hemodynamic alterations in such a patient is important for successful perioperative management. We have discussed the anaesthetic considerations in a 12 year-old girl with complex congenital heart disease ultimately palliated by a Fontan operation, who was posted for Botox injections for upper limb spasticity under general anaesthesia.

A patient posted for vaginal hysterectomy was administered subarachnoid block, which failed, so was repeated in one space above. The block failed again, after waiting for 30 min. Patient gave a history of scorpion bite twice, once at the age of 17 years on her right foot and again about 8 months back. Thereafter, balanced general anaesthesia was given. On eighth post-operative day, after explaining about her possible special condition (?Resistance to local anaesthetic agents), the patient was given left median, ulnar and radial nerve blocks at the wrist and local infiltration near the anatomical snuff box. There was neither sensory nor motor block. The scorpion venom is known to affect the pumping mechanism of sodium channels in the nerve fibres, which are involved in the mechanism of action of local anaesthetic drugs, it may be responsible for the development of 'resistance' to the action of local anaesthetic agents.

Chiari I malformation (CM-I) manifests with tonsillar herniation below foramen magnum. These patients are at high risk of respiratory depression and bulbar dysfunction in the perioperative period with underlying obstructive sleep apnea. However, the safe use of both general and regional anaesthesia has been documented in a known CM-I parturients. We describe the successful management of a patient who had hypercapnic respiratory failure in the post-anaesthetic care unit following an uneventful subarachnoid block for left knee replacement surgery. This patient was retrospectively diagnosed with occult CM-I and moderate to severe obstructive sleep apnea in the postoperative period.

Peppermint oil is easily available as a constituent of medicines. A near fatal case due to ingestion of toxic dose of oral peppermint oil is being reported. The patient came in a comatosed state and was in shock. She was managed with mechanical ventilation and ionotropes. Her vital parameters reached normal within 8 hours and became conscious by 24 hours. The side effects of peppermint oil are considered to be mild but this case report warns that ingestion of oral toxic doses of peppermint oil could be dangerous.