Black carbon aerosol quantification over north-west Himalayas: Seasonal heterogeneity, source apportionment and radiative forcing.

Continuous measurements of Black Carbon (BC) aerosol mass concentrations were carried at Dehradun (30.33°N, 78.04°E, 700 m amsl), a semi-urban site in the foothills of north-westHimalayas, India during January 2011-December 2017. We reported both the BC seasonal variations as well as mass concentrations from fossil fuel combustion (BCff) and biomass burning (BCbb) sources. Annual mean BC exhibited a strong seasonal variability with maxima during winter (4.86 ±â€¯0.78 µg m-3) followed by autumn (4.18 ±â€¯0.54 µg m-3), spring (3.93 ±â€¯0.75 µg m-3) and minima during summer (2.41 ±â€¯0.66 µg m-3). Annual averaged BC mass concentrations were 3.85 ±â€¯1.16 µg m-3 varying from 3.29 to 4.37 µg m-3 whereas BCff and BCbb ranged from 0.11 to 7.12 µg m-3 and 0.13-3.6 µg m-3. The percentage contributions from BCff and BCbb to total BC are 66% and 34% respectively, indicating relatively higher contribution from biomass burning as compared to other locations in India. This is explained using potential source contribution function (PSCF) and concentration weighted trajectories (CWT) analysis which reveals the potential sources of BC originating from the north-west and eastern parts of IGP and the western part of the Himalayas that are mostly crop residue burning and forest fire regions in India. The annual mean ARF at top-of-atmosphere (TOA), at surface (SUR), and within the atmosphere (ATM) were found to be -14.84 Wm-2, -43.41 Wm-2, and +28.57 Wm-2 respectively. To understand the impact of columnar aerosol burden on ARF, the radiative forcing efficiency (ARFE) was estimated and averaged values were -31.81, -91.63 and 59.82 Wm-2 τ-1 for TOA, SUR and ATM respectively. The high ARFE within the atmosphere indicates the dominance of absorbing aerosol (BC and dust) over Northwest Himalayas.

Impact of biomass burning on regional aerosol optical properties: A case study over northern India.

The present study examines the spatial, seasonal and inter annual variation of biomass burning and its impact on regional aerosol optical properties over Northern India using multi-satellite aerosol observations: Active fire points, AOD (550 nm) and AE (550-860 nm) from MODIS retrievals during January 2003-December 2017 and AAOD (388 nm), SSA (388 nm) and AI from OMI UV retrievals during January 2005-December 2017. Results from MODIS active fire count statistics indicate an increase in the number of fire occurrences (average 1477 fires per year) over India in a period of 15 years (2003-2017). The dominant fire seasons are (i) Pre-monsoon (March to May) accounting to more than 45% and (ii) Post-Monsoon having 24% of total annual fires counts. However, the crop residue burning hotspot region located in Punjab and Haryana, constitutes 26% of the total fires in India. At an average, 15456 (77.08%) fire counts were reported during the paddy season, whereas 3296 (16.44%) fire counts during wheat season respectively. The crop residue burning over the northwest IGP (Punjab) significantly affect the aerosol optical properties locally as well in the downwind regions during post-monsoon season i.e., crop residue fires increased by 4% (170 fires per year) with corresponding AOD, AAOD & AI increased by 8%, 9% & 11% respectively. The satellite observation shows large gradient of aerosol parameters from north-west to south-east along the Himalayan foot-hills which indicates the regional transport of smoke aerosols over the region. This is also supported by ground based AOD observations at four locations (Patiala, Delhi, Dehradun and Kanpur) and Black Carbon measurements at two locations (Patiala and Dehradun). The climatological averaged values of ground based AOD550 for Patiala, Delhi, Dehradun and Kanpur are 0.52 ±â€¯0.26, 0.75 ±â€¯0.40, 0.45 ±â€¯0.24 and 0.57 ±â€¯0.29 respectively whereas BC concentrations are 8.43 ±â€¯3.14 µg m-3 & 3.36 ±â€¯1.26 µg m-3 for Patiala & Dehradun respectively. Comparison of MODIS derived AOD agrees well with ground based AODs (overall R = 0.86 and RMSE = 0.14). In addition, CALIPSO shows the maximum amount of biomass burning smoke aerosols present within the atmospheric boundary layer and some cases it extending up to 2-3 km altitudes. The smoke aerosol transport pathways originated from crop residue burning were analyzed using Hysplit forward trajectories. The results reveal that majority of smoke aerosols are transported to eastern IGP, central India and adjacent oceanic regions during post-monsoon season.

Comparative clinical study of gabapentin and pregabalin for postoperative analgesia in laparoscopic cholecystectomy.

BACKGROUND: Reduction in central sensitization by gabapentinoids that include gabapentin and pregabalin may reduce acute postoperative pain. AIMS: The aim of this study is to evaluate postoperative analgesic benefit and efficacy in patients administered with oral gabapentin or pregabalin as premedication for laparoscopic cholecystectomy under general anesthesia. SETTINGS AND DESIGN: Randomized, prospective, and comparative study. MATERIALS AND METHODS: In this study, recruited patients were randomly allocated in three groups. Groups A, B, and C received 2 capsules of B complex, 3 capsules of 300 mg gabapentin each, and 2 capsules of 75 mg pregabalin, respectively, each in 30 patients of each group, 1 h before induction of anesthesia. Postoperative efficacy among these three groups was compared with respect to increase in duration of analgesia, reduction in postoperative pain scores, total postoperative requirements of analgesics and side effects. STATISTICAL ANALYSIS: Mean and standard deviation were calculated. Test of analysis between two groups was done by t-test and among three groups by analysis of variance, and then P value was calculated. RESULTS: Pregabalin and gabapentin group had lower visual analog scale (VAS) score (P < 0.05), prolonged timing of first rescue analgesic (4.67 ± 14.79 vs. 158 ± 13.10 vs. 343.16 ± 9.69) min, and less opioid consumption (169.87 ± 20.32 vs. 116.13 ± 14.08 vs. 64.67 ± 16.69) mg compared to placebo group. Between the gabapentinoids, pregabalin group had lower VAS score, prolonged timing of first rescue analgesic, and less opioids consumption than the gabapentin group. CONCLUSION: It is concluded in this study that pregabalin group had lower VAS score, prolonged timing of first rescue analgesic, and less opioids consumption than the gabapentin group. Both gabapentinoids had better postoperative analgesic profile than placebo.

Seasonal, interannual, and long-term variabilities in biomass burning activity over South Asia.

The seasonal, interannual, and long-term variations in biomass burning activity and related emissions are not well studied over South Asia. In this regard, active fire location retrievals from the Moderate Resolution Imaging Spectroradiometer (MODIS), the retrievals of aerosol optical depth (AOD) from MODIS Terra, and tropospheric column NO2 from Ozone Monitoring Instrument (OMI) are used to understand the effects of biomass burning on the tropospheric pollution loadings over South Asia during 2003-2013. Biomass burning emission estimates from Global Fire Emission Database (GFED) and Global Fire Assimilation System (GFAS) are also used to quantify uncertainties and regional discrepancies in the emissions of carbon monoxide (CO), nitrogen oxide (NOx), and black carbon (BC) due to biomass burning in South Asia. In the Asian continent, the frequency of fire activity is highest over Southeast Asia, followed by South Asia and East Asia. The biomass burning activity in South Asia shows a distinct seasonal cycle that peaks during February-May with some differences among four (north, central, northeast, and south) regions in India. The annual biomass burning activity in north, central, and south regions shows an increasing tendency, particularly after 2008, while a decrease is seen in northeast region during 2003-2013. The increase in fire counts over the north and central regions contributes 24 % of the net enhancement in fire counts over South Asia. MODIS AOD and OMI tropospheric column NO2 retrievals are classified into high and low fire activity periods and show that biomass burning leads to significant enhancement in tropospheric pollution loading over both the cropland and forest regions. The enhancement is much higher (110-176 %) over the forest region compared to the cropland (34-62 %) region. Further efforts are required to understand the implications of biomass burning on the regional air quality and climate of South Asia.

Randomised Controlled Trial of Day-Case Laparoscopic Cholecystectomy vs Routine Laparoscopic Cholecystectomy.

Many randomised controlled trials conducted worldwide favours for day-case laparoscopic cholecystectomy, but questions have been raised regarding its application in developing country like ours. Hence, considering it a high time to review current practices, we conducted this trial to report our experience with day-case laparoscopic cholecystectomy and to access its feasibility and safety in our set-up. Data from 65 patients with symptomatic gallstone were randomised to perform laparoscopic cholecystectomy either as day-case procedure or as routine (conventional) procedure. Complication, quality of life, satisfaction, post-operative nausea and vomiting and pain were assessed. Ninety-seven per cent (31/32) of day-case laparoscopic cholecystectomy patients were successfully discharged with mean duration of 8.9 ± 4.54 h, which was 3.33 ± 1.45 days (72.92 ± 34.8 h) in routine (conventional) laparoscopic cholecystectomy group. There was no significant difference in complication, quality of life, satisfaction, post-operative nausea and vomiting and pain between the two groups. Day-case laparoscopic cholecystectomy is a safe, feasible and beneficial procedure in our set-up. Patient acceptance in terms of quality of life and satisfaction was similar to that of routine laparoscopic cholecystectomy.

Comparative clinical study of effect of neostigmine and ketamine for postoperative analgesia.

The purpose of the study was to evaluate and compare the role of neostigmine and ketamine as an additive to epidural bupivacaine to prolong the duration of postoperative analgesia. A double-blind randomised study was done on 60 adult patients, of both sexes, between 18 and 50 years, belonging to ASA grades I and II, undergoing below umbilical surgeries under epidural anaesthesia. All the patients were divided into three groups of 20 each to receive 20 ml of 0.5% bupivacaine with either 1 ml of normal saline, 100 mg of neostigmine or 50 mg of ketamine (both diluted with 1 ml normal saline). The mean (+/- SD) time to the first rescue analgesic administration was significantly prolonged by neostigmine [543.30 (+/- 133.40) minutes] and ketamine [292.00 (+/- 71.93) minutes] compared to the control group with saline [212.80 (+/- 62.49) minutes]. Postoperative 24-hour pain score was also less in neostigmine group. When compared to ketamine group neostigmine showed superior postoperative pain relief. Both neostigmine and ketamine demonstrated better haemodynamic stability with less incidence of hypotension. There was no increased incidence of nausea and vomiting or any other side-effects. In conclusion, it can be said neostigmine is a good adjuvant to epidural block to produce adequate pain relief without increased incidence of adverse effects.

Fibromyalgia and myofascial pain syndrome-a dilemma.

SUMMARY: Pain and fatigue associated to the musculoskeletal system are among the leading causes of patients to visit their physicians and nearly one-third of such patients suffer from fibromyalgia. Fibromyalgia syndrome (FMS) is a chronic debilitating disorder characterized by widespread pain with tenderness in specific areas, leading to fatigue, headache and sleep disorder. Myofascial Pain Syndrome (MPS), is also a localized musculoskeletal pain producing condition whose diagnostic and management criteria differ from FMS but still considered by many only a subtype of FMS. Till date no exact cause has been held responsible for these painful conditions, therefore treatment of these disorders is always a challenge. The therapies are not precise but multimodal including pharmacological and alternative approaches. This article describes the existing knowledge pertaining to these conditions in regard of causative factors diagnosis and management.

Fulminant pulmonary edema after intramuscular ketamine.

PURPOSE: To report an unusual case of pulmonary edema following intramuscular ketamine administration. CLINICAL FEATURES: An eight-year-old, healthy girl presented for dressing of first degree burns on dorsum of hand. Ten minutes after administration of 125 mg ketamine im, she developed laboured breathing, cyanosis, and bilateral crepitations and arterial blood gas analysis showed PaO2 55 mmHg. There was no evidence of upper airway obstruction. On intubating the trachea, pink frothy fluid emerged from the tube. She was diagnosed as a case of neurogenic pulmonary edema. She was managed with positive pressure ventilation with positive end expiratory pressure, morphine and furosemide. With this treatment she showed a favourable recovery. CONCLUSION: Ketamine was given im to aid burns dressing in this case because it has distinct advantages above the other anesthetic agents including that of being a good analgesic which is absorbed by im route. Its use led to the development of pulmonary edema.

Effect of pH adjustment of bupivacaine on onset and duration of epidural anaesthesia.

The effect of pH adjustment of bupivacaine on onset and duration of sensory and motor block was studied in 45 patients undergoing lower abdominal and lower limb surgery. The study was done in 3 groups with the mean pH adjustment of 5.85, 7.14 and 7.21. Each patient was given 30 ml of 0.4% pH adjusted bupivacaine solution in epidural space. Onset of sensory block and duration were noticed by pin-prick method while motor block was observed by asking the patient to raise the thigh. It was observed that increase in pH of bupivacaine solution quickens the onset of sensory and motor block and increases the overall duration of neural blockade.