On-treatment decline in MELD score predicts one-month transplant-free survival in rodenticidal hepatotoxicity patients treated with low-volume plasma exchange.

BACKGROUND AND AIM: Plasma exchange (PLEX) improves survival in patients with rodenticidal hepatotoxicity. However, predictors of treatment response are unknown. We aimed at assessing predictors of response to PLEX treatment in these patients. METHODS: Patients with rodenticidal hepatotoxicity from 2014 to 2023 managed in our department were included in this study. Kochi criteria (model for end-stage liver disease [MELD] score ≥ 36 or international normalized ratio [INR] ≥ 6 with hepatic encephalopathy [HE]) derived specifically for rodenticidal hepatotoxicity (PubMed IDentifier [PMID]: 26310868) were used to assess need for liver transplantation. We analyzed predictors of survival at one month. ∆Bilirubin, ∆MELD score and ∆INR were calculated as percentage change of the parameter after third PLEX session (or after last PLEX if < 3 PLEX sessions done) from baseline pre-PLEX value. RESULTS: Of 200 patients with rodenticidal hepatotoxicity, 114 patients were treated with low-volume PLEX (PLEX-LV). No patient had liver transplantation. Of 78 patients who fulfilled Kochi criteria, 32 patients were PLEX-LV eligible and underwent PLEX-LV (M: 10; age: 20.5, 7-70 years; median, range; acute liver failure: 24). Twenty-two (69%; acute liver failure: 14) of the 32 patients were alive at one month. Presence of HE (p = 0.03) and ∆MELD (p < 0.001) were significant predictors on univariate analysis, while ∆MELD (aOR = 0.88, 95% CI: 0.79-0.98, p = 0.01) was the only significant independent predictor of one-month transplant-free survival. Area under receiver operating characteristic (ROC) for ∆MELD was 0.93 (95% CI:0.85-1.00) and a decrease of ≥ 20% in MELD score while on PLEX-LV had 90% sensitivity and 90% specificity in predicting one-month survival. CONCLUSIONS: Decline in MELD while on PLEX-LV independently predicted one-month transplant-free survival in rodenticidal hepatotoxicity patients. This may help guide decision on stopping PLEX-LV in patients predicted to respond to treatment and to consider alternate treatment options in non-responders.

Genetic predisposition and high exposure to colistin in the early treatment period as independent risk factors for colistin-induced nephrotoxicity.

Colistin is known to cause nephrotoxicity due to its extensive reabsorption and accumulation in renal tubules. In vitro studies have identified the functional role of colistin transporters such as OCTN2, PEPT2, megalin, and P-glycoprotein. However, the role of these transporter gene variants in colistin-induced nephrotoxicity has not been studied. Utilizing targeted next-generation sequencing, we screened for genetic polymorphisms covering the colistin transporters (SLC15A1, SLC15A2, SLC22A5, LRP2, and ABCB1) in 42 critically ill patients who received colistimethate sodium. The genetic variants rs2257212 ((NM_021082.4):c.1048C>G) and rs13397109 ((NM_004525.3):C.7626C > T) were identified as being associated with an increased incidence of acute kidney injury (AKI) on Day 7. Colistin area under the curve (AUC) was predicted using a previously published pharmacokinetic model of colistin. Using logistic regression analysis, the predicted 24-h AUC of colistin was identified as an important contributor for increased odds of AKI on Day 7. Among 42 patients, 4 (9.5%) were identified as having high predisposition to colistin-induced AKI based on the presence of predisposing genetic variants. Determination of the presence of the abovementioned genetic variants and early therapeutic drug monitoring may reduce or prevent colistin-induced nephrotoxicity and facilitate dose optimization of colistimethate sodium.

Model-Informed Rationale for Early Therapeutic Drug Monitoring of Colistin in Critically Ill Patients.

Adequate colistin exposure is important for microbiological clearance. This study was performed in critically ill patients >18 years old to develop a simplified nonparametric pharmacokinetic (PK) model of colistin for routine clinical use and to determine the role of dose optimization. The Non-Parametric Adaptive Grid algorithm within the Pmetrics software package for R was used to develop a PK model from 47 patients, and external validation of the final model was performed in 13 patients. A 1-compartment multiplicative gamma error model with 0-order input and first-order elimination of colistin was developed with creatinine clearance and serum albumin as covariates on elimination rate constant. An R2 for observed vs individual predicted colistin concentrations of 0.92 was obtained in the validation cohort. High interindividual variability in colistin steady-state area under the plasma concentration-time curve (AUC) from from 120 hours to 144 hours (coefficient of variation = 80.1%) and a high interoccasion variability (median coefficient of variation of AUC from time 0 to hours predicted every 8 hours for initial 96 hours after starting colistin = 23.8) was predicted in patients who received this antibiotic for a period of over 152 hours (n = 22). With the model-suggested dose regimen, only 20% of simulated profiles achieved AUC from time 0 to 24 hours in the range of 50 to 60 mg â€¢ h/L due to high variability in population PK. In this group of patients, steady-state colistin concentrations were predicted to be achieved >96 hours after initiation of colistimethate sodium. This study advocates the need for early and repeated therapeutic drug monitoring and dose optimization in critically ill patients to achieve adequate therapeutic concentration of colistin.

Patient Characteristics and Outcomes in Necrotizing Soft-tissue Infections: Results from a Prospective Cohort Study in a Tertiary Care Center Intensive Care Unit in South India.

Background: Necrotizing soft tissue infections (NSTIs) are life-threatening infections characterized by progressive destruction of muscle, fascia, and overlying subcutaneous tissue. Prospective studies in the field are few, and data from the Indian subcontinent are bleak. Prompt diagnosis and timely treatment are critical for optimal outcomes. The aims of this study are to provide detailed information on the clinical profile of patients with NSTIs and to identify predictors of mortality in order to pick up reversible factors that may improve outcomes. Materials and methods: This study was a prospective cohort study of adult patients with NSTIs in a tertiary center in South India. All patients who were admitted to the surgical intensive care unit (ICU) of the institute with a diagnosis of NSTI were screened and enrolled. All patients were managed according to the local protocol for treatment of NSTIs and intensive care support. Results: In our cohort of patients, simple and multiple logistic regression analysis showed that four factors, namely, AKIN stage 3, shock, need for mechanical ventilation for more than 3 days, and low serum albumin values were found to be significantly associated with higher mortality. Conclusion: The successful management of these patients calls for early diagnosis, resuscitation, surgical debridement, appropriate and timely antibiotics, and early ventilatory weaning before multi-organ failure associated with shock and AKI occurs. How to cite this article: Kurian GP, Korula PJ, Jacob JM, Desha AMK, Karuppusami R, Kandasamy S. Patient Characteristics and Outcomes in Necrotizing Soft-tissue Infections: Results from a Prospective Cohort Study in a Tertiary Care Center Intensive Care Unit in South India. Indian J Crit Care Med 2022;26(4):452-456.

Clinical efficacy of novel combinations of older beta-lactam and beta-lactamase inhibitors: Where are the evidences?

India is well known for the rampant growth of ESBLs that jeopardized the clinical utility of standalone beta-lactam. Pharmaceutical organizations fancied to rescue these beta-lactams by combining them with generic beta-lactamase inhibitors despite such combinations were never investigated in non-clinical or clinical studies. Lack of stringency in regulatory review practices allowed the market entry of these combinations. CSE 1034 (ceftriaxone, sulbactam and EDTA) and cefoperazone sulbactam are the most irrational antibiotics in clinical use. The effectiveness of such combinations relies on multiple factors such as relative beta-lactamase stability of the standalone beta-lactam, the inhibitory potency of the beta-lactamase inhibitor and more importantly the adequacy of the dose incorporated in the formulation. Unfortunately, none of the unconventional BL-BLI inhibitor combinations marketed in India has been subjected to such evaluations. Therefore, their therapeutic utility is uncertain. Besides questionable therapeutic utility, sub-optimal exposures would lead to the selection of resistant clones.

Association between SpO2/FiO2 Ratio and PaO2/FiO2 Ratio in Different Modes of Oxygen Supplementation.

BACKGROUND: Acute hypoxemic respiratory failure (AHRF) is a major factor for increased mortality in the intensive care unit (ICU). We hypothesized that the noninvasive index SpO2/FiO2 (SF) ratio can be used as a surrogate to invasive index PaO2/FiO2 (PF) as SF ratio correlates with PF ratio in all modes of oxygen supplementation. PATIENTS AND METHODS: Patients with acute respiratory failure admitted to the intensive care unit were enrolled in this retrospective cross-sectional study. Fraction of inspired oxygen (FiO2), method of oxygen supplementation, and partial pressure of arterial oxygen (PaO2) were noted from the ABG reports in the medical records. The corresponding SpO2 was noted from the nurse's chart. The calculated SF and PF ratios were recorded, and correlation between the same was noted in different methods of oxygen administration. RESULTS: A total of 300-sample data were collected. Pearson's correlation was used to quantify the relationship between the variables. The study showed a positive correlation, r = 0.66 (p <0.001), between PF ratio and SF ratio. SF threshold values were 285 and 323 for corresponding PF values of 200 and 300 with a sensitivity and specificity in the range of 70 to 80%. In addition, SF and PF could also be used interchangeably irrespective of the mode of oxygen supplementation, as the median values of PF ratio (p = 0.06) and SF ratio (p = 0.88) were not statistically significant. CONCLUSION: In patients with AHRF, the noninvasive SF ratio can be used as a surrogate to invasive index PF in all modes of oxygen supplementation. HOW TO CITE THIS ARTICLE: Babu S, Abhilash KPP, Kandasamy S, Gowri M. Association between SpO2/FiO2 Ratio and PaO2/FiO2 Ratio in Different Modes of Oxygen Supplementation. Indian J Crit Care Med 2021;25(9):1001-1005.

Voluntary Prone Position for Acute Hypoxemic Respiratory Failure in Unintubated Patients.

Severe hypoxemic respiratory failure is frequently managed with invasive mechanical ventilation with or without prone position (PP). We describe 13 cases of nonhypercapnic acute hypoxemic respiratory failure (AHRF) of varied etiology, who were treated successfully in PP without the need for intubation. Noninvasive ventilation (NIV), high-flow oxygen via nasal cannula, supplementary oxygen with venturi face mask, or nasal cannula were used variedly in these patients. Mechanical ventilatory support is offered to patients with AHRF when other methods, such as NIV and oxygen via high-flow nasal cannula, fail. Invasive mechanical ventilation is fraught with complications which could be immediate, ranging from worsening of hypoxemia, worsening hemodynamics, loss of airway, and even death. Late complications could be ventilator-associated pneumonia, biotrauma, tracheal stenosis, etc. Prone position is known to improve oxygenation and outcome in adult respiratory distress syndrome. We postulated that positioning an unintubated patient with AHRF in PP will improve oxygenation and avoid the need for invasive mechanical ventilation and thereby its complications. Here, we describe a series of 13 patients with hypoxemic respiratory of varied etiology, who were successfully treated in the PP without endotracheal intubation. Two patients (15.4%) had mild, nine (69.2%) had moderate, and two (15.4%) had severe hypoxemia. Oxygenation as assessed by PaO2/FiO2 ratio in supine position was 154 ± 52, which improved to 328 ± 65 after PP. Alveolar to arterial (A-a) O2 gradient improved from a median of 170.5 mm Hg interquartile range (IQR) (127.8, 309.7) in supine position to 49.1 mm Hg IQR (45.0, 56.6) after PP. This improvement in oxygenation took a median of 46 hours, IQR (24, 109). Thus, voluntary PP maneuver improved oxygenation and avoided endotracheal intubation in a select group of patients with hypoxemic respiratory failure. This maneuver may be relevant in the ongoing novel coronavirus disease pandemic by potentially reducing endotracheal intubation and the need for ventilator and therefore better utilization of critical care services. HOW TO CITE THIS ARTICLE: Rao SV, Udhayachandar R, Rao VB, Raju NA, Nesaraj JJJ, Kandasamy S, et al. Voluntary Prone Position for Acute Hypoxemic Respiratory Failure in Unintubated Patients. Indian J Crit Care Med 2020;24(7):557-562.

Is It All Clear if Procalcitonin Clears in Acute Pancreatitis?

How to cite this article: Kandasamy S. Is It All Clear if Procalcitonin Clears in Acute Pancreatitis? Indian J Crit Care Med 2020;24(3):149-150.

Susceptibility profile, resistance mechanisms & efficacy ratios of fosfomycin, nitrofurantoin & colistin for carbapenem-resistant Enterobacteriaceae causing urinary tract infections.

Background & objectives: The escalation in carbapenem resistance among Enterobacteriaceae has resulted in a lack of effective therapeutic alternatives. Older antimicrobials, fosfomycin, nitrofurantoin and colistin for urinary tract infections (UTIs) caused by carbapenem-resistant Enterobacteriaceae (CRE) may be effective treatment options. The objectives of this study were to evaluate the utility of fosfomycin, nitrofurantoin and colistin in treating UTI caused by CRE and molecular characterization of the plasmid-mediated carbapenem resistance mechanisms. Methods: Consecutive, non-duplicate isolates of CR Escherichia coli and Klebsiella spp. from urine cultures were included (n=150). Minimum inhibitory concentrations (MIC) were determined by E-test (fosfomycin and nitrofurantoin) and broth microdilution (colistin). Efficacy ratios were derived by dividing susceptibility breakpoints by observed MIC values of the drugs for the isolates. Isolates were screened for genes coding for carbapenemases using multiplex PCR. Fosfomycin, nitrofurantoin and colistin-resistant isolates were screened for plasmid-borne resistance genes fos A3, oqx AB and mcr-1, respectively using PCR. Results: Among E. coli, 98.9, 56 and 95 per cent isolates were susceptible to fosfomycin, nitrofurantoin and colistin, respectively, while 94 and 85 per cent of Klebsiella spp. were susceptible to fosfomycin and colistin, respectively. The efficacy ratios indicated fosfomycin as the drug of choice for UTI caused by CR E. coli and Klebsiella spp., followed by colistin. The blaNDM gene was most common, followed by blaOXA48-like. Plasmid-borne genes encoding resistance to fosfomycin, nitrofurantoin and colistin were absent. Interpretation & conclusions: With increasing resistance against the current treatment options, older drugs may emerge as effective options. Molecular screening of resistant isolates is essential to prevent the spread of plasmid-borne resistance against these drugs.

Impact of an antimicrobial stewardship intervention in India: Evaluation of post-prescription review and feedback as a method of promoting optimal antimicrobial use in the intensive care units of a tertiary-care hospital.

OBJECTIVE: Antimicrobial stewardship programs (ASPs) are effective in developed countries. In this study, we assessed the effectiveness of an infectious disease (ID) physician-driven post-prescription review and feedback as an ASP strategy in India, a low middle-income country (LMIC). DESIGN AND SETTING: This prospective cohort study was carried out for 18 months in 2 intensive care units of a tertiary-care hospital, consisting of 3 phases: baseline, intervention, and follow up. Each phase spanned 6 months. PARTICIPANTS: Patients aged ≥15 years receiving 48 hours of study antibiotics were recruited for the study. METHODS: During the intervention phase, an ID physician reviewed the included cases and gave alternate recommendations if the antibiotic use was inappropriate. Acceptance of the recommendations was measured after 48 hours. The primary outcome of the study was days of therapy (DOT) per 1,000 study patient days (PD). RESULTS: Overall, 401 patients were recruited in the baseline phase, 381 patients were recruited in the intervention phase, and 379 patients were recruited in the follow-up phase. Antimicrobial use decreased from 831.5 during the baseline phase to 717 DOT per 1,000 PD in the intervention phase (P < .0001). The effect was sustained in the follow-up phase (713.6 DOT per 1,000 PD). De-escalation according to culture susceptibility improved significantly in the intervention phase versus the baseline phase (42.7% vs 23.6%; P < .0001). Overall, 73.3% of antibiotic prescriptions were inappropriate. Recommendations by the ID team were accepted in 60.7% of the cases. CONCLUSION: The ID physician-driven implementation of an ASP was successful in reducing antibiotic utilization in an acute-care setting in India.

Intravenous clonidine as a part of balanced anaesthesia for controlled hypotension in functional endoscopic sinus surgery: A randomised controled trial.

BACKGROUND AND AIMS: Controlled hypotension with balanced anaesthesia minimises blood loss. This study was done to evaluate the effectiveness of intravenous clonidine as a single bolus dose to establish controlled hypotension during functional endoscopic sinus surgery (FESS). METHODS: This randomised, double-blind, placebo-controlled study was done in a tertiary hospital in India. Sixty American Society of Anesthesiologists physical status I and II patients (18-65 years) undergoing FESS were randomly allocated to one of the two groups. Placebo group (group A, n = 30) received sterile water whereas the clonidine group (group B, n = 30) received 3µg/kg of clonidine intravenously, 30 min prior to induction of anaesthesia. The primary outcome was to achieve a target mean arterial blood pressure (MAP) of 55-65 mmHg intraoperatively. The secondary outcomes measured were requirement of additional fentanyl and metoprolol, intra-operative blood loss, surgeon's opinion on the surgical field, pain, sedation score and complications requiring treatment. RESULTS: Target MAP was easily achieved in clonidine group as against the placebo group (P < 0.001). Significant reduction in intra-operative blood loss (P = 0.0449), a better surgical site scoring (P = 0.02), less requirement of additional hypotensive drugs and good analgesia (P = 0.01) were seen in clonidine group. The complication rates were similar in both the groups. CONCLUSION: Clonidine is effective in achieving controlled hypotension in patients undergoing FESS. It reduces intra-operative blood loss, requirement of additional hypotensive drugs, improves the surgical field and offers good analgesia without significant side effects.

Predictive Value of Serum Myoglobin and Creatine Phosphokinase for Development of Acute Kidney Injury in Traumatic Rhabdomyolysis.

INTRODUCTION: Rhabdomyolysis (RM) is a condition where there is injury to striated muscle fibers causing release of myoglobin, creatine phosphokinase (CPK), and other intracellular contents into the circulation. High myoglobin levels cause acute kidney injury (AKI). Trauma is the most common cause of RM and development of complications related to the degree of myoglobin released. Currently, the degree of RM is assessed and treatment is instituted based on serum CPK. As myoglobin is the direct cause of AKI, we set out to determine if serum myoglobin is a more reliable predictor than CPK for the development of AKI in traumatic RM. METHODOLOGY: A prospective observational study of 90 patients was admitted to the surgical Intensive Care Unit/high dependency unit of a tertiary hospital with traumatic RM whose serum CPK >5000 U/L. Along with standard treatment including intravascular volume optimization and hemodynamic stabilization, they were treated with "crush protocol." Daily/twice a day, serum CPK and myoglobin were estimated. Categorical data are expressed as frequency and percentage, and the continuous variables are presented as mean (standard deviation) or median (interquartile range) based on normality. Other statistical analyses were done using the Chi-square test, independent t-test, and rank sum test based on normality. RESULTS: Fourteen out of 90 patients developed AKI and one patient required renal replacement therapy. CPK value of >12,000 U/l was identified to have 64% sensitivity and 56% specificity for developing AKI whereas serum myoglobin value of >5000 ng/ml was identified to have 78% sensitivity and 77% specificity for developing AKI. CONCLUSION: Following traumatic RM, in patients on "crush protocol," serum myoglobin is a more sensitive and specific test than serum CPK, for predicting AKI.