General anaesthesia can affect every aspect of ventilation. It produces dose dependent depression of control of respiration. Carbon dioxide response curve is shifted to the right. Muscle tone is reduced and the airway can get obstructed. One of the most prominent changes is reduction in functional residual capacity (FRC) with the adoption of supine function and induction of anaesthesia. The closing capacity increases with age. The atelectasis that occurs consequent to the fall in FRC and increasing age is compounded by the use of high concentrations of oxygen, cephalad movement of the diaphragm, residual effect of muscle relaxants and inadequate analgesia after thoracic or abdominal surgery. One of the important causes of ventilation perfusion mismatch during anaesthesia is atelectasis. This has been shown to contribute to hypoxia as well as increased postoperative pulmonary complications. A lot of research is being conducted as to reduce the effects of atelectasis during anaesthesia, including the best ventilator strategy during anaesthesia. Most inhalation anaesthetics are good bronchodilators. Inhalation anaesthetics depress hypoxic pulmonary vasoconstriction (HPV) beyond 1 MAC. The movement of ciliary movements is reduced with the use of dry gases. All these can increase postoperative pulmonary complications which are important causes of postoperative morbidity. Appropriate preoperative preparation has to be combined with optimal management of ventilation intraoperatively to minimise postoperative pulmonary complications. The role of lower tidal volume, use of positive end-expiratory pressure, limiting oxygen concentrations and the utility of recruitment manoeuvres are increasingly being recognised and have been the topics of recent research.

Background: Concerns have been expressed about risk of exposure to exhaled aerosols to ICU personnel. AIM: To quantify amount of aerosol collected at the exhaust outlet of mechanical ventilators operated with and without filters in the expiratory limb. Methods: Two categories of ventilators were tested: (1) Ventilators without Proprietary Filters: Servo-i (Maquet) and Galileo (Hamilton) and (2) Ventilator with proprietary filters: PB 840 (Covidien). Each ventilator was attached to a simple test lung and operated with VT 500 ml, RR 20 bpm, PIF 50 L/min, PEEP 5 cmH2O. Four separate doses of albuterol (2.5 mg/3mL) were administered via jet nebuliser (eValueMed, Tri-anim) placed at the “Y”. In Experiment A, a filter (Respirgard 303) was placed at the exhaust port. In Experiment B, two filters were attached to the ventilators without proprietary filters: (1) at the end of expiratory limb and (2) at the exhaust outlet. Drug was eluted from filters and measured using spectrophotometry. Results: Drug deposited at the exhaust port without expiratory filtering was >160 fold higher than with expiratory filtering. The collecting filter used in this study was less efficient than the proprietary filter designed for use with the ventilator. Regardless of type of filter used, placement of filter in the expiratory limb reduced secondhand aerosol exposure significantly. Conclusion: Risk of secondhand exposure to exhaled aerosol can account for >45% of nominal dose as well as droplet nuclei produced by patients. Using expiratory filters decreases risk of exposure to aerosol released to the atmosphere during mechanical ventilation.

Introduction: Arterial blood gas (ABG) testing requires puncture of an artery to obtain a blood sample for analysis. It is a common procedure in the hospital to allow assessment of pulmonary gas exchange. Compared with vein puncture, arterial puncture is more difficult, requires deeper needle insertion and is more painful for the patient. Cryoanalgesia would offer a noninvasive, nonpharmacologic, inexpensive and readily available tool to reduce pain associated with arterial puncture. This study sought to determine whether cryoanalgesia in the form of ice application could be an effective analgesic when applied before arterial puncture. Methodology: This was a prospective study with a convenience sample of intensive care unit patients on oxygen therapy with a physician order for an ABG test. The intervention group had a plastic bag of ice applied to their wrists for 3 min before drawing an ABG sample from the radial artery. The control group had an ABG sample drawn from the radial artery without the application of ice. Pain from the arterial puncture was measured with a pain rating scale. Results: Subjects pretreated with ice reported less pain from arterial puncture compared with subjects in the control group (median pain rating scale 2.00 Inter Quartile Range (IQR) 2.00-1.00 Vs 4.00 IQR 5.00-3.25, P = 0.01). Conclusions: Use of cryoanalgesia (Ice bag) reduces the pain associated with arterial puncture.

There are a limited number of Indian studies which evaluated the efficacy of subglottic suctioning in reducing the occurrence of ventilator associated pneumonia among intubated patients. Aim: To evaluate the efficacy of subglottic suctioning in reducing the occurrence of ventilator associated pneumonia. Methodology: This randomised controlled trial, was conducted in the Medical and Surgical Intensive Care Units. Twenty patients were enrolled, ten in the intervention and ten in the control group. Background variables, Clinical profile and Clinical Pulmonary Infection Score (CPIS) were evaluated. On admission the subjects, who met the inclusion criteria were randomised using lottery method to either intervention or control group. Pretest CPIS assessment was done for both the groups on the day of admission. Post-test CPIS assessment was carried out on the day of extubation or tracheostomy or when the subject had a temperature spike greater than 1020F. Results: There was a significant reduction in the occurrence of ventilator associated pneumonia among patients in the intervention group than in the control group (P < 0.01). Conclusion: The results confirmed that the implementation of subglottic suctioning is effective in reducing the occurrence of ventilator associated pneumonia among intubated patients.

Introduction: There are limited Indian studies that evaluate the nurses’ knowledge of VAP prevention bundle. Aim: Our study aimed to assess the effectiveness of a structured teaching programme on VAP bundle among staff nurses in critical care unit. Methodology: The prospective, quasi-experimental study was conducted among critical care nurses. The final sample (n=57) nurses was selected by purposive sampling technique on the basis of set inclusion criteria. The nurses were first assessed for their knowledge of guidelines to prevent VAP. They were then educated using a standard teaching module and the assessment performed again. Results: There was a statistically significant increase in the knowledge level of participants by a mean (±S.D) 5.68 (±2.8) score with 95% C.I (4.94 – 6.43) and p <0.001. Conclusion: The 2-hour teaching module significantly enhanced nurses’ knowledge towards evidence based guidelines for the prevention of VAP

The outbreak of H1N1, a virus of swine origin was detected in Mexico in late March and early April 2009. World Health Organization (WHO) in 2009 reported that 195 countries have reported confirmed human cases of H1N1. This pandemic virus infection though was self limited mild to moderate disease; there were reports of fatal complications especially in children and young adults. There was little or no immunity to this virus by humans and this virus targeted lower respiratory tract and caused pneumonia which was rapidly progressing. Approximately 10-30% of those infected with H1N1 required intensive care. Though the pandemic was declared to be over in August 2010, the concern of clinical management of H1N1 infected patient still remains challenging. The differences in presentation, clinical course and ventilatory management of two cases with pregnancy as a risk factor for complicated H1N1 infection are compared in this case report.

Introduction: Chronic obstructive pulmonary disease (COPD) is associated with intermittent exacerbation with deterioration in their symptoms of dyspnoea and cough with expectoration. These patients often require repeated hospitalisation for the control of these exacerbations. Repeated hospitalisation can have persistent psychological effects on these patients. Methodology: This was a prospective, observational study. Twenty nine patients admitted to the medical intensive care unit (ICU) with a diagnosis of COPD were enrolled. They were assessed for anxiety and depression using hospital anxiety and depression scale (HADS). Hospital anxiety and depression questionnaire were addressed to patient twice: once just before discharge from ICU and again just before discharge from ward and the results were compared. Result: Out of twenty nine patients, 8 (27.5%) showed anxiety, 6 (20.6%) patients were having borderline anxiety and 15 (51.7%) patients had no anxiety. Ten (35%) patients showed depression, 13 (45%) patients had borderline depression and 6 (20%) patients had no depression during intensive care management. In the ward, the same patients were assessed again for anxiety. Five (17.2%) patients showed anxiety, 10 (34.8%) patients had borderline anxiety and 14 (48.2%) patients had no anxiety during ward stay. Similarly, four (13.7%) patients showed depression, 13 (44.8%) patients had borderline depression and 12 (41.3%) patients had no depression. Conclusion: Anxiety and depression is common in COPD patients and it is more during ICU stay compared to ward stay.