Ashok Shankar Badhe

Ventilator-associated pneumonia: A review

Ventilator-associated pneumonia (VAP) is the most frequent intensive-care-unit (ICU)-acquired infection, with an incidence ranging from 6 to 52% [1,2,3,4]. Several studies have shown that critically ill patients are at high risk for getting such nosocomial infections [3,4]. VAP continues to be a major cause of morbidity, mortality and increased financial burden in ICUs [5,6,7,8]. Over the years there has been a significant advance in our understanding of ventilator associated pneumonia. This article reviews the various aspects of VAP such as definition, risk factors, etiological agents, diagnosis, treatment and prevention with emphasis on the recent advances.

Ventilator-associated pneumonia: role of colonizers and value of routine endotracheal aspirate cultures

OBJECTIVES To determine the role of colonizers in the causation of ventilator-associated pneumonia (VAP) and the value of routine pre-VAP endotracheal aspirate (EA) cultures in appropriately treating VAP. METHODS A prospective observational cohort study was conducted over a period of 15 months. Two hundred patients on mechanical ventilation for>48h were studied. RESULTS Acinetobacter spp (33.7%) and Pseudomonas spp (29.8%) were the most common colonizers. Of the 200 patients, 36 developed VAP. In 20 VAP patients, the pre-VAP EA culture-based strategy was not useful. However, in the remaining 16 VAP patients, a pre-VAP EA culture-based strategy would have appropriately treated 13 (81%; 95% confidence interval (CI) 62-100%), in comparison to only nine (56%; 95% CI 32-80%) by the American Thoracic Society (ATS) strategy. The seven patients in whom the ATS guidelines were inappropriate had Acinetobacter spp and Pseudomonas spp resistant to the higher antibiotics recommended by the ATS for multidrug-resistant pathogens. The positive predictive values of Pseudomonas aeruginosa, Acinetobacter baumannii, and methicillin-resistant Staphylococcus aureus (MRSA) isolated from pre-VAP EA cultures were 88%, 83%, and 100%, respectively. CONCLUSION VAP patients should be treated based on ATS guidelines, but whenever P. aeruginosa, A. baumannii, and MRSA are isolated from pre-VAP EA cultures, the initial antibiotic therapy should be extended to treat these.

Comparison of analgesic efficacy of transversus abdominis plane block with direct infiltration of local anesthetic into surgical incision in lower abdominal gynecological surgeries

Background: Transversus abdominis plane block is a safe, simple and effective technique of providing analgesia for lower abdominal surgeries with easily identifiable landmarks. Aims: To compare the analgesic efficacy of transversus abdominis plane block with that of direct infiltration of local anesthetic into surgical incision in lower abdominal procedures. Settings and Design: Prospective randomized controlled trial in lower abdominal surgeries done under general anesthesia. Materials and Methods: 52 ASA I-II patients undergoing lower abdominal gynecological procedures under general anesthesia were divided randomly into two groups each after written informed consent. A bilateral TAP block was performed on Group T with 0.25% bupivacaine 0.6 ml/kg with half the volume on either side intra-operatively after skin closure before extubation using a short bevelled needle, whereas Group I received local infiltration intra-operatively after skin closure with the same amount of drug. The time taken for the first rescue analgesic and visual analog score (VAS) was noted, following which, the patient was administered intravenous morphine 0.1 mg/kg and connected to an intravenous patient controlled analgesia system with morphine for 24 hrs from the time of block administration. 24 h morphine requirement was noted. VAS and sedation scores were noted at 2, 4, 6 and 24 h postoperatively. Statistical Analysis Used: The results were analyzed with SPSS 16. A P value < 0.05 was considered significant. Duration of analgesia and 24 h morphine requirement was analysed by Students t-test. VAS scores, with paired comparisons at each time interval, were performed using the t-test or Mann-Whitney U-test, as appropriate. Categorical data were analyzed using Chi square or Fishers exact test. Results: In Group T, the time to rescue analgesic was significantly more and the VAS scores were lower (P = 0.001 and 0.003 respectively). The 24 hr morphine requirement and VAS at 2, 4, 6 and 24 h were less in the Group T (P = 0.001). Incidence of PONV was significant in Group I (P = 0.043), whereas Group T were less sedated at 2 and 4 h (P = 0.001 and 0.014). Conclusions: Transversus abdominis plane block proved to be an effective means of analgesia for lower abdominal surgeries with minimal side-effects.

Effect of intravenous lignocaine on perioperative stress response and post-surgical ileus in elective open abdominal surgeries: a double-blind randomized controlled trial

Perioperative stress response can be detrimental if excessive and prolonged. Intravenous (i.v.) lignocaine, while being an effective analgesic, has the added benefit of anti‐inflammatory activity. This study was done to assess the effect of i.v. lignocaine on operative stress response and post‐surgical ileus after elective open abdominal surgeries.

Comparison of i-gel supraglottic airway and LMA-ProSeal™ in pediatric patients under controlled ventilation.

Background: i-gel™ and the ProSeal™ laryngeal mask airway (PLMA) are two supraglottic airway devices with gastric channel used for airway maintenance in anesthesia. This study was designed to evaluate the efficacy of i-gel compared with PLMA for airway maintenance in pediatric patients under general anesthesia with controlled ventilation. Materials and Methods: A total of 60 American Society of Anesthesiologists physical status 1 and 2 patients were included in the study and randomized to either i-gel or PLMA group. After induction of anesthesia using a standardized protocol for all the patients, one of supraglottic airway devices was inserted. Insertion parameters, ease of gastric tube insertion and fiber-optic scoring of the glottis were noted. Airway parameters such as end-tidal carbon dioxide (EtCO2), peak airway pressures and leak airway pressures were noted. Patients were observed for any complications in the first 12 h of the post-operative period. Results: Both groups were comparable in terms of ease of insertion, number of attempts and other insertion parameters. Ease of gastric tube insertion, EtCO2, airway pressures (peak and leak airway pressure) and fiber-optic view of the glottis were comparable in both groups. There were no clinically significant complications in the first 12 h of the post-operative period. Conclusion: i-gel is as effective as PLMA in pediatric patients under controlled ventilation.

Randomized Controlled Trial on the Efficacy of Bilateral Superficial Cervical Plexus Block in Thyroidectomy

As thyroid surgery is being performed as an ambulatory procedure, recent studies concerning post thyroidectomy analgesia have focused on regional techniques such as bilateral superficial cervical plexus block (BSCPB) and bilateral combined superficial and deep cervical plexus block. But, data regarding the efficacy of BSCPB are controversial. Hence we compared the efficacy of BSCPB with 0.25% bupivacaine with and without clonidine in thyroidectomy, as preventative analgesia.

The comparison of stroke volume variation with central venous pressure in predicting fluid responsiveness in septic patients with acute circulatory failure

Purpose: The present study was designed to investigate the efficacy of stroke volume variation (SVV) in predicting fluid responsiveness and compare it to traditional measures of volume status assessment like central venous pressure (CVP). Methods: Forty-five mechanically ventilated patients in sepsis with acute circulatory failure. Patients were not included when they had atrial fibrillation, other severe arrhythmias, permanent pacemaker, or needed mechanical cardiac support. Furthermore, excluded were patients with hypoxemia and a CVP >12. Patients received volume expansion in the form of 500 ml of 6% hydroxyethyl starch. Results: The volume expansion-induced increase in  cardiac index (CI) was >15% in 29 patients (labeled responders) and <15% in 16 patients (labeled nonresponders). Before volume expansion, SVV was higher in responders than in nonresponders. Receiver operating characteristic curves analysis showed that SVV was a more accurate indicator of fluid responsiveness than CVP. Before volume expansion, an SVV value of 13% allowed discrimination between responders and nonresponders with a sensitivity of 78% and a specificity of 89%. Volume expansion-induced changes in CI weakly and positively correlated with SVV before volume expansion. Volume expansion decreased SVV from 18.86 ± 4.35 to 7.57 ± 1.80 and volume expansion-induced changes in SVV moderately correlated with volume expansion-induced changes in CI. Conclusions: When predicting fluid responsiveness in mechanically ventilated patients in septic shock, SVV is more effective than CVP. Nevertheless, the overall correlation of baseline SVV with increases in CI remains poor. Trends in SVV, as reflected by decreases with volume replacement, seem to correlate much better with increases in CI.

Reliability of Kirby-Bauer disk diffusion method for detecting meropenem resistance among non-fermenting gram-negative bacilli

BACKGROUND Meropenem is empirically used as a last resort for the treatment of infections by non-fermenting gram-negative bacilli (NFGNB). Minimum inhibitory concentration (MIC) determined using agar or broth dilution methods is widely used for testing meropenem resistance. However, it is not possible in resource-poor settings. AIM A prospective study was performed to evaluate the reliability of Kirby-Bauer disk diffusion (KBDD) method for detecting meropenem resistance among NFGNB. MATERIALS AND METHODS A total of 146 NFGNB consisting of 56 Acinetobacter baumannii, 24 Acinetobacter lwoffii, 48 Pseudomonas aeruginosa and 18 Pseudomonas spp. were included in the study. All the isolates were tested simultaneously by both KBDD method and agar dilution method. RESULTS Very major errors were not observed with A. baumannii, A. lwoffii and P. aeruginosa, while other Pseudomonas spp. showed a very major error rate of about 5.6%. The major error rates observed with A. baumannii, A. lwoffii, P. aeruginosa and Pseudomonas spp. were 1.8%, 0%, 2.1% and 28.6%, respectively. All the isolates showed a good correlation between zone diameters (KBDD method) and MICs (agar dilution method). The sensitivity and specificity of KBDD method for detecting meropenem resistance was above 90% for all the NFGNB except Pseudomonas spp. CONCLUSIONS The KBDD method can be reliably used for routine testing of meropenem resistance in A. baumannii, A. lwoffii and P. aeruginosa. However, further studies are needed before employing this technique for detecting meropenem resistance in Pseudomonas spp.

Comparison of induction and recovery characteristics of intravenous midazolam and thiopentone in paediatric halothane general anaesthesia

Fifty children were randomized for induction with 0.3 mg kg−1 midazolam or 5 mg kg−1 thiopentone. Efficacy, safety, recovery time, amnesic effect, tolerability and recovery characteristics were compared. Midazolam required longer for induction and recovery from anaesthesia. The safety profile was similar with both drugs.

Acute pulmonary edema as a complication of Anti-snake Venom therapy

Polyvalent Anti-snake Venom (ASV) is a life-saving antivenin for severe envenomation due to snake bite in India. ASV infusion is occasionally associated with severe allergic reactions, i.e. anaphylaxis and death. We report a rare instance of non-cardiogenic pulmonary edema due to ASV infusion in an eleven years old boy.