Ravi S Tripathi

Endogenous Opioids in Wound-Site Neutrophils of Sternotomy Patients

Background Postoperative pain management is a critical aspect of patient care. The inflammatory state of the post-sternotomy surgical wound sensitizes nerve endings, causing pain. Unrelieved or improperly managed pain compromises wound healing. Peripheral opioid receptors play a major role in analgesia, particularly under inflammatory conditions where both opioid receptor expression and efficacy are increased. Leukocytic opioid peptides include β-endorphin (END), met-enkephalin (ENK), and dynorphin-A (DYN), with END and ENK being predominant. Methodology/Principal Findings This work represents the first study of inflammatory cells collected from post-sternotomy wounds of patients undergoing cardiac surgery including coronary artery bypass grafting (CABG). Wound fluid (WF) and cells were collected from sternal wounds using a JP Blake drain at 24, 48, and 72 hours post sternum closure. Anti-CD15 staining and flow cytometry revealed that polymorphonuclear neutrophils (PMN) are the predominant cells present in wound fluid collected post-surgery. Compared to peripheral blood (PB) derived PMN, significant increases in CD177+/CD66b+ PMN were observed suggesting activation of wound-site PMN. Such activation was associated with higher levels of opioid peptide expression in PMN derived from WF. Indeed, increased level of opioid peptides in sternal wound environment was noted 72 h post-surgery. We demonstrate that WF contains factors that can significantly induce POMC transcription in human PMNs. IL-10 and IL-4 were abundant in WF and both cytokines significantly induced POMC gene expression suggesting that WF factors such as IL-10 and IL-4 contribute towards increased opioid peptide expression in wound-site PMN. Conclusions/Significance This approach provided a unique opportunity to study the cross-talk between inflammation and opioid peptides in PMN at a sternotomy wound-site. Wound-site PMN exhibited induction of END and ENK. In addition, sternal wound fluid significantly induced END expression in PMN. Taken together, these data constitute first clinical evidence that human wound-site PMNs are direct contributors of opioids at the sternal wound-site.

Veno-venous ECMO: a synopsis of nine key potential challenges, considerations, and controversies

BackgroundFollowing the 2009 H1N1 Influenza pandemic, extracorporeal membrane oxygenation (ECMO) emerged as a viable alternative in selected, severe cases of ARDS. Acute Respiratory Distress Syndrome (ARDS) is a major public health problem. Average medical costs for ARDS survivors on an annual basis are multiple times those dedicated to a healthy individual. Advances in medical and ventilatory management of severe lung injury and ARDS have improved outcomes in some patients, but these advances fail to consistently “rescue” a significant proportion of those affected.DiscussionHere we present a synopsis of the challenges, considerations, and potential controversies regarding veno-venous ECMO that will be of benefit to anesthesiologists, surgeons, and intensivists, especially those newly confronted with care of the ECMO patient. We outline a number of points related to ECMO, particularly regarding cannulation, pump/oxygenator design, anticoagulation, and intravascular fluid management of patients. We then address these challenges/considerations/controversies in the context of their potential future implications on clinical approaches to ECMO patients, focusing on the development and advancement of standardized ECMO clinical practices.SummarySince the 2009 H1N1 pandemic ECMO has gained a wider acceptance. There are challenges that still must be overcome. Further investigations of the benefits and effects of ECMO need to be undertaken in order to facilitate the implementation of this technology on a larger scale.

Anesthesia care for subcutaneous implantable cardioverter/defibrillator placement: a single-center experience.

BACKGROUNDnThe recently approved subcutaneous implantable cardioverter/defibrillator (S-ICD) uses a single extrathoracic subcutaneous lead to treat life-threatening ventricular arrhythmias, such as ventricular tachycardia and ventricular fibrillation. This is different from conventional transvenous ICDs, which are typically implanted under sedation. Currently, there are no reports regarding the anesthetic management of patients undergoing S-ICD implantation.nnnSTUDY OBJECTIVESnThis study describes the anesthetic management and outcomes in patients undergoing S-ICD implantation and defibrillation threshold (DFT) testing.nnnMETHODSnThe study population consists of 73 patients who underwent S-ICD implantation. General anesthesia (n = 69, 95%) or conscious/deep sedation (n = 4, 5%) was used for device implantation.nnnMEASUREMENTSnSystolic blood pressure (SBP) and heart rate were recorded periprocedurally for S-ICD implantation and DFTs. Major adverse events were SBP <90 mm Hg refractory to vasopressor agents, significant bradycardia (heart rate <45 beats per minute) requiring pharmacologic intervention and, severe pain at the lead tunneling site and the S-ICD generator insertion site based on patient perception.nnnINTERVENTIONSnOf the 73 patients, 39 had SBP <90 mm Hg (53%), and intermittent boluses of vasopressors and inotropes were administered with recovery of SBP. In 2 patients, SBP did not respond, and the patients required vasopressor infusion in the intensive care unit.nnnMAIN RESULTSnAlthough the S-ICD procedure involved extensive tunneling and a mean of 2.5 ± 1.7 DFTs per patient, refractory hypotension was a major adverse event in only 2 patients. The mean baseline SBP was 132.5 ± 22.0 mm Hg, and the mean minimum SBP during the procedure was 97.3 ± 9.2 mm Hg (P < .01). There was also a mean 13-beats per minute decrease in heart rate (P < .01), but no pharmacologic intervention was required. Eight patients developed severe pain at the lead tunneling and generator insertion sites and were adequately managed with intravenous morphine.nnnCONCLUSIONSnAmong a heterogeneous population, anesthesiologists can safely manage patients undergoing S-ICD implantation and repeated DFTs without wide swings in SBP and with minimal intermittent pharmacologic support.

Negative pressure pulmonary edema with laryngeal mask airway use: Recognition, pathophysiology and treatment modalities.

Negative pressure pulmonary edema (NPPE) following the use of the laryngeal mask airway (LMA) is an uncommon and under-reported event. We present a case of a 58-year-old male, who developed NPPE following LMA use. After biting vigorously on his LMA, the patient developed stridor upon emergence, with concurrent appearance of blood-tinged, frothy sputum and pulmonary edema. He subsequently required three days of mechanical ventilation. After discontinuation of mechanical ventilation the patient continued to require additional pulmonary support using continuous positive airway pressure, with a full facemask, to correct the persistent hypoxemia. His roentgenographic findings demonstrated an accelerated improvement with judicious administration of intravenous furosemide.

An overview of end-of-life issues in the intensive care unit

The population of the earth is aging, and as medical techniques, pharmaceuticals, and devices push the boundaries of human physiological capabilities, more humans will go on to live longer. However, this prolonged existence may involve incapacities, particularly at the end-of-life, and especially in the intensive care unit. This arena involves not only patients and families, but also care givers. It involves topics from economics to existentialism, and surgery to spiritualism. It requires education, communication, acceptance of diversity, and an ultimate acquiescence to the inevitable. Here, we present a comprehensive overview of issues in the care of patients at the end-of-life stage that may cause physicians and other healthcare providers, medical, ethical, social, and philosophical concerns in the intensive care unit.

Role of nutrition support in adult cardiac surgery: a consensus statement from an International Multidisciplinary Expert Group on Nutrition in Cardiac Surgery

Nutrition support is a necessary therapy for critically ill cardiac surgery patients. However, conclusive evidence for this population, consisting of well-conducted clinical trials is lacking. To clarify optimal strategies to improve outcomes, an international multidisciplinary group of 25 experts from different clinical specialties from Germany, Canada, Greece, USA and Russia discussed potential approaches to identify patients who may benefit from nutrition support, when best to initiate nutrition support, and the potential use of pharmaco-nutrition to modulate the inflammatory response to cardiopulmonary bypass. Despite conspicuous knowledge and evidence gaps, a rational nutritional support therapy is presented to benefit patients undergoing cardiac surgery.

Civilian nuclear incidents: An overview of historical, medical, and scientific aspects.

Given the increasing number of operational nuclear reactors worldwide, combined with the continued use of radioactive materials in both healthcare and industry, the unlikely occurrence of a civilian nuclear incident poses a small but real danger. This article provides an overview of the most important historical, medical, and scientific aspects associated with the most notable nuclear incidents to date. We have discussed fundamental principles of radiation monitoring, triage considerations, and the short- and long-term management of radiation exposure victims. The provision and maintenance of adequate radiation safety among first responders and emergency personnel are emphasized. Finally, an outline is included of decontamination, therapeutic, and prophylactic considerations pertaining to exposure to various radioactive materials.

Letter From Tripathi et al Regarding Article, “Perioperative Dexmedetomidine Improves Outcomes of Cardiac Surgery”

In a recent issue of Circulation , Ji and colleagues1 report improved morbidity and mortality with perioperative use of dexmedetomidine in cardiac surgery. We commend the authors for exploring the benefits of dexmedetomidine on outcomes despite drug cost. The mortality benefits at in-hospital, 30-day, and 1-year points are notable.nnAlthough outcomes were risk adjusted, the patients who received dexmedetomidine had significantly shorter cardiopulmonary bypass duration (181.8 vs 199.8 minutes) and lower incidence of intra-aortic balloon pump requirement (6.87% vs 14.13%). The multivariate model assessing delirium did not include cardiopulmonary bypass duration, yet longer durations are associated with an increase in postoperative delirium.2 Furthermore, the multivariate model assessing mortality did not …

Continuous glucose monitoring identifies relationship between optimized glycemic control and post-discharge acute care facility needs

ObjectiveHyperglycemia is an independent risk factor in hospitalized patients for adverse outcomes, even if patients are not diabetic. We used continuous glucose monitoring to evaluate whether glycemic control (hyperglycemia) in the first 72xa0h after an intensive care admission was associated with the need for admission to a post discharge long-term medical facility.ResultsWe enrolled 59 coronary artery bypass grafting patients. Poor glycemic control was defined as greater than 33% of continuous glucose monitoring values <u200970 and >u2009180xa0mg/dL (group 1); and then these patients were reevaluated with a less strict definition of poor glycemic control with greater than 25% of continuous glucose valuesu2009<u200970 andu2009>u2009180xa0mg/dL (group 2). In group 1 4/10 (40.0%) whose glucose was not well controlled went to an extended care post discharge facility as opposed to 6/49 (12.2%) that were well controlled. In reevaluation as group 2, 5/14 (35.7%) whose glucose was not well controlled went to an extended care post discharge facility as opposed to 5/45 (11.1%) who were well controlled. Admission to a post discharge facility was increased in patients with poor glycemic control pu2009=u20090.045 and pu2009=u20090.042 for group 1 and group 2, and with odds ratios of 4.8 (95% CI 1.0–22.5) and 4.4 (95% CI 1.0–19.4), respectively.

Dermal tattooing following intravenous methylene blue for refractory hypotension after coronary artery bypass grafting

The authors present an image of a middle-aged male after coronary artery bypass grafting who received intravenous methylene blue for refractory hypotension that resulted in dermal tattooing/staining of the venous vasculature of his left shoulder and left upper chest. Republished with permission from: Bhatt AM, Tripathi RS, Moran KR, Papadimos TJ. Dermal tattooing following intravenous methylene blue for refractory hypotension after coronary artery bypass grafting. OPUS 12 Scientist 2012;6(1):11.