Deepak Govil

Excellent outcome of living donor liver transplantation in patients with hepatopulmonary syndrome: a single centre experience.

Hepatopulmonary syndrome (HPS) worsens the prognosis of cirrhosis and liver transplantation is only definitive treatment. There is paucity of data about role of living donor liver transplantation (LDLT) in HPS.

Intensive Care in India: The Indian Intensive Care Case Mix and Practice Patterns Study

Aims: To obtain information on organizational aspects, case mix and practices in Indian Intensive Care Units (ICUs). Patients and Methods: An observational, 4-day point prevalence study was performed between 2010 and 2011 in 4209 patients from 124 ICUs. ICU and patient characteristics, and interventions were recorded for 24 h of the study day, and outcomes till 30 days after the study day. Data were analyzed for 4038 adult patients from 120 ICUs. Results: On the study day, mean age, Acute Physiology and Chronic Health Evaluation (APACHE II) and sequential organ failure assessment (SOFA) scores were 54.1 ± 17.1 years, 17.4 ± 9.2 and 3.8 ± 3.6, respectively. About 46.4% patients had ≥1 organ failure. Nearly, 37% and 22.2% patients received mechanical ventilation (MV) and vasopressors or inotropes, respectively. Nearly, 12.2% patients developed an infection in the ICU. About 28.3% patients had severe sepsis or septic shock (SvSpSS) during their ICU stay. About 60.7% patients without infection received antibiotics. There were 546 deaths and 183 terminal discharges (TDs) from ICU (including left against medical advice or discharged on request), with ICU mortality 729/4038 (18.1%). In 1627 patients admitted within 24 h of the study day, the standardized mortality ratio was 0.67. The APACHE II and SOFA scores, public hospital ICUs, medical ICUs, inadequately equipped ICUs, medical admission, self-paying patient, presence of SvSpSS, acute respiratory failure or cancer, need for a fluid bolus, and MV were independent predictors of mortality. Conclusions: The high proportion of TDs and the association of public hospitals, self-paying patients, and inadequately equipped hospitals with mortality has important implications for critical care in India.

Pulse Oximetry and Capnography

Pulse oximetry and capnography are essential components of respiratory monitoring in the intensive care unit.

Good outcome of living donor liver transplantation in drug induced acute liver failure: a single centre experience.

Drug‐induced acute liver failure (ALF) is associated with high mortality. There is limited literature on results of living donor liver transplantation (LDLT).

Integrative weaning index: New kid on the block!

Weaning covers the entire process of liberating the patient from mechanical ventilation and endotracheal tube.[1] Till date, no weaning index has been shown to accurately predict weaning success. The decision to wean a patient by clinical judgment of the physician is not always correct and is met with a high incidence of weaning failure. The challenge for critical care physicians is to balance the act of successfully weaning the patient from ventilator against the dreadful need of re-intubation. The need for accurate prediction applies to all phases of weaning, beginning with reductions in mechanical support, as patients are increasingly able to support their own breathing, followed by trials of unassisted breathing, which often precede extubation and ending with extubation.[2] An ideal weaning index should be able to discriminate between those patients who can be successfully weaned from mechanical ventilation and those who are unable to be weaned. Many factors can influence the weaning outcome: The functional parameters used as indexes of weaning, the criteria used to define failure or success, the moment at which the patients are studied, different clinical practice from unit to unit, and the different populations.[3] Esteban et al.[4] along with other Spanish Lung Failure Collaborative Group researchers introduced weaning by attempting a 2-h spontaneous breathing trial (SBT) and concluded that two-thirds of ventilated patients can be successfully discontinued from ventilator after a 2-h SBT. Based on these findings, the critical care physicians have been practicing SBT and if the patient fulfills the objective and subjective readiness criteria, the trachea is extubated. Nevertheless, around 12–25% of the patients experience respiratory insufficiency postextubation and require re-intubation.[5] Hence, this method does not have accurate predictive value. Yang and Tobin[6] in 1991 developed a new weaning index and named it rapid shallow breathing index (RSBI) and had concluded that RSBI is the single most accurate predictor of weaning success and has a predictive value of 89%. Since then, this index has been evaluated in almost 22 studies published. Lee et al.[7] suggested that RSBI could be employed more usefully as a trend monitor rather than as a spot check. Various studies have found that RSBI <105 breaths/min/L has a sensitivity, 65–96%; specificity, 0–73%; and hence only modestly predicts extubation success. Nemer et al.[8] in 2009 defined the integrative weaning index (IWI) and its predictiveness for successful weaning. The principle of IWI is to integrate three important components of breathing in a single equation: The respiratory mechanics, oxygenation, and breathing pattern. The principle that static compliance and SaO2 are directly proportional to weaning success and RSBI values are inversely proportional to weaning success have been incorporated in the equation. The authors of the present study[9] have based their study on the above-mentioned article and compared IWI with routine weaning criteria. They have shown IWI can accurately predict weaning failure even in patients who tolerate SBTs. To incorporate IWI in routine weaning prediction model, we have to understand certain important points. First, there are very limited studies on IWI and most of the studies have majority of chronic obstructive pulmonary disease patients as their study subjects. Hence, the question whether this weaning index accurately predict successful weaning in other conditions of acute respiratory failure needs a larger extrapulmonary database as the respiratory mechanics may change with the disease. Second, when the patients are in the weaning phase, calculation of static respiratory compliance with patients’ breathing spontaneously can give erroneous readings. So, to get an accurate reading, the patients respiratory effort either has to be abolished or the patient has to voluntarily become apneic. To calculate IWI, static compliance plays a very important role and one has to be sure about the method of obtaining the correct compliance value. In the present study, the authors have done justice to the first point by enrolling patients with varied etiologies of respiratory failure although the total number of patients is less. They also have taken into account the second point by taking the digital display value of static respiratory compliance by selectively deleting the values where patient had taken respiratory effort. The positive predictive value of IWI in the study is 97%, which is almost the same as the original article which had 99%. In this present study, the authors have been able to predict statistically significant weaning success. Even with limited literature on IWI, the concept looks appealing with such high sensitivity and specificity. To make IWI as a routine predictor of weaning success could be an excellent advancement in the respiratory management, but require more studies.

Optic nerve sheath diameter measurement using bedside ultrasound: Is it accurate?

Raised intracranial pressure (ICP) is a complication not just of traumatic brain injury and other acute cerebral insults, but also of a number of general medical conditions. Monitoring of ICP is of paramount importance in Neurointensive Care Unit. Increased ICP causes brain insult which may be associated with increased mortality and poor neurological outcomes.[1,2,3] Bedside clinical diagnosis can be difficult as early clinical signs may be misinterpreted, and heavy reliance on cross-sectional imaging studies may further delay diagnosis. Ultrasound is a bedside imaging modality that is increasingly available in most critical care units. The diameter of the optic nerve sheath has been found to be a strong predictor of raised ICP, with a high sensitivity and specificity in multiple studies and in a systematic review.[4] The optic nerve sheath is bound more loosely to the optic nerve closer to the globe. This loose binding creates a much larger, and potentially more distensible, subarachnoid space in this region, which can appear bulbous on ultrasound.[5] Consistent with this, the optic nerve sheath is at its most distensible anteriorly, where it is potentially most reflective of raised ICP. As per a 1996 study, using modern ultrasonography (USG) techniques showed that optic nerve sheath diameter (ONSD) increased by up to 60% at a distance of 3mm behind the globe in comparison to only 35% at 10 mm.[6] This has been confirmed in subsequent studies, indicating that a position 3 mm behind the globe is preferred for measurement.[7] Measurements made at this point are more reproducible since ultrasound contrast is greater at this depth with a linear probe. While papilloedema viewed by funduscopy may take the time to develop, dilatation of the optic nerve sheath occurs much earlier and may be a near instantaneous manifestation of raised ICP.[6,8] Studies of sonographic ONSD have mainly correlated findings with clinical and radiological signs and symptoms of elevated ICP. Intraventricular measurement is the gold standard for measuring ICP. These measurement devices carry many risks, including hemorrhage and infection. These complications partly account for increasing interest in noninvasive methods such as neuroimaging, transcranial Doppler sonography, ONSD USG and computed tomography/magnetic resonance imaging (CT/MRI). In addition, invasive methods may not be available to individual patients due to contraindications, such as coagulopathy, thrombocytopenia, or the lack of local facilities. The optic nerve and its surrounding sheath can be accurately imaged and measured on MRI using a fat-suppressed T2-weighted sequence. MRI is often spoken of as a reference test for ONSD, as it has a higher spatial resolution, and the images offer a more representative calculation of the mean diameter than CT. While Lagreze et al. contend the accuracy of MRI exceeds sonographic methods for determining ONSD,[9] Bauerle showed good scan-rescan reproducibility and good observer agreement in 15 healthy volunteers.[10] Two questions that need to be answered when we talk about bedside measurement of ONSD by ultrasound for diagnosis of raised ICP: First, does the bedside ultrasound measurement of ONSD correlate strongly with a neuroimaging technique such as an orbital MRI; and secondly what should be the cut-off of ONSD values to determine raised ICP. The authors of the current study[11] have attempted to resolve the first question regarding the correlation of ONSD measured by bedside ultrasound and MRI. They have studied 100 adult patients of either sex, diagnosed with meningoencephalitis who were to undergo MRI of the brain and measured the ONSD 3 mm behind the globe using a bedside ultrasound and correlated its measurement with that measured by MRI at the same point. They found a high level of correlation between the ultrasound measurement and MRI measurement of ONSD. A Bland-Altman analysis was done to show agreement between both methods of measurement of ONSD, the analysis showed a significant correlation between ocular sonography and MRI. Previous Studies performed between both modalities to measure ONSD were done in subjects with normal ICP or in cadavers. This is the first study done with a relatively large group subjects with meningoencephalitis and it adds further proof that bedside ultrasound readings of ONSD may be as accurate as MRI, given the proper technique and training. With regards to the second question, there is wide variation in the literature regarding in the optimal cut-off values, when ONSD was compared with invasive ICP monitoring, ranging from 4.8 to 5.9 mm.[12,13] The reasons cited for these varied cut-off include: Heterogeneous patient populations, varied methods for confirming raised ICP, and ethnic difference among the patient population. The current authors have selected cut-off values of 4.6 mm for females, and 4.8 mm for males in accordance to a study by Shirodkar et al.[14] on 101 Indian patients who demonstrated a high level of sensitivity and specificity with these cut-off values for the diagnosis of intracranial hypertension as evident on CT or MRI imaging. However, the current authors have limited themselves to comparing the numerical accuracy of ONSD values obtained with USG and MRI. They have not commented on the presence or absence of MRI findings of raised ICP and hence have not corroborated the cut-off values of ONSD for raised ICP in Indian patients which as per Shirodkar et al.[14] was found to be somewhat less than those from previous studies. Nevertheless, the high level of correlation between MRI and a bedside ultrasound found in this study suggests that ultrasound can be used to detect acute rise in ICP with a high level of accuracy and despite its limitations, USG ONSD measurement is likely to be more reliable than clinical assessment in the diagnosis of intracranial hypertension and has the potential to become one of the first line modalities in detecting increased ICP especially in situations when altered sensorium or administration of sedative medication precludes such assessment.[15] Further, larger studies need to be performed on Indian population to decide an optimal cut-off value for raised ICP and that needs to be correlated with a standard which could be either direct measurement of ICP or by means of characteristic findings on neuroimaging.

Management of potential organ donor: Indian Society of Critical Care Medicine: Position statement

PurPose and scoPe of the stateMent The position statement for management of organ donors is prepared by the Indian Society of Critical Care Medicine (ISCCM) with an objective of providing the standard perspective for the management of potential organ/tissue donors after brain death in adults only, regardless of the availability of technology. This document should be used as guidance only and does not a substitute for proper clinical decision‐making in particular circumstances of any case. The endorsement of ISCCM does not imply that the statements given in the document are applicable in all or in a particular case; however, they may provide guidance for the users thus utilizing maximum organs from brain‐dead patients. Thus, care of potential brain‐dead organ donor is “caring for multiple recipients” [Table 1].

Incidence of posterior wall penetration during internal jugular vein cannulation: A comparison of two techniques using real-time ultrasound

Background and Aims: The true incidence of penetration of the posterior wall (through-and-through puncture) of the internal jugular vein (IJV) during cannulation is unknown. This may have implications if there is hematoma formation, penetration and/or inadvertent cannulation of an underlying carotid artery. This study compared the incidence of posterior wall puncture during IJV cannulation using ultrasound guidance versus traditional landmarks-guided technique. Methods: One hundred and seventy adult patients admitted to a gastro-liver Intensive Care Unit who required central venous lines were randomly divided into Group A: IJV cannulation using anatomical landmark-guided technique and Group B: IJV cannulation using real-time ultrasound guidance. In both groups, a second investigator followed the needle path using real-time ultrasound. The incidence of posterior wall puncture, number of attempts for successful cannulation, incidence of inadvertent arterial punctures and occurrence of complications such as hematoma formation and pneumothorax were recorded. Results: Significantly more (37/80, 46%) patients in Group A had posterior wall puncture compared to 19/90 (21%) in Group B. Incidence of arterial puncture was 8/80 (10%) in Group A, 5/90 (5.5%) in Group B. The number of attempts for venous cannulation and hematoma formation was significantly less in Group B. Conclusion: Real-time ultrasound-guided IJV cannulation significantly reduces but does not wholly eliminate the incidence of posterior venous wall penetrations. It also significantly reduces the incidence of inadvertent arterial punctures and number of attempts for successful cannulation.

Can integrative weaning index be a routine predictor for weaning success

Sir, We would like to bring you notice that the equation for integrative weaning index (IWI) has been mentioned incorrectly in the article by El-Baradey et al.;[1] the correct equation is as follows: IWI = Crs Χ SaO2 /(f/Vt).[2,3] Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest