Vitamin C for Vasoplegia After Cardiopulmonary Bypass: A Case Series

Perioperative care in infective endocarditis

Patients undergoing surgery for acute infective endocarditis are among those with the highest risk. Their preoperative condition has significant impact on outcomes. There are specific issues related with the preoperative situation, intraoperative findings, and postoperative management. In this narrative review, focus is placed on the most critical aspects in the perioperative period including the management and weaning from mechanical ventilation, the management of vasoplegia, the management of the chest open, antithrombotic therapy, transfusion, coagulopathy, management of atrial fibrillation, the duration of antibiotic therapy, and pacemaker implantation.

Vitamin C deficiency can lead to pulmonary hypertension: a systematic review of case reports

BACKGROUND

In the early literature, unintentional vitamin C deficiency in humans was associated with heart failure. Experimental vitamin C deficiency in guinea pigs caused enlargement of the heart. The purpose of this study was to collect and analyze case reports on vitamin C and pulmonary hypertension.

METHODS

We searched Pubmed and Scopus for case studies in which vitamin C deficiency was considered to be the cause of pulmonary hypertension. We selected reports in which pulmonary hypertension was diagnosed by echocardiography or catheterization, for any age, sex, or dosage of vitamin C. We extracted quantitative data for our analysis. We used the mean pulmonary artery pressure (mPAP) as the outcome of primary interest.

RESULTS

We identified 32 case reports, 21 of which were published in the last 5 years. Dyspnea was reported in 69%, edema in 53% and fatigue in 28% of the patients. Vitamin C plasma levels, measured in 27 cases, were undetectable in 24 and very low in 3 cases. Diet was poor in 30 cases and 17 cases had neuropsychiatric disorders. Right ventricular enlargement was reported in 24 cases. During periods of vitamin C deficiency, the median mPAP was 48 mmHg (range 29-77 mmHg; N = 28). After the start of vitamin C administration, the median mPAP was 20 mmHg (range 12-33 mmHg; N = 18). For the latter 18 cases, mPAP was 2.4-fold (median) higher during vitamin C deficiency. Pulmonary vascular resistance (PVR) during vitamin C deficiency was reported for 9 cases, ranging from 4.1 to 41 Wood units. PVR was 9-fold (median; N = 5) higher during vitamin C deficiency than during vitamin C administration. In 8 cases, there was direct evidence that the cases were pulmonary artery hypertension (PAH). Probably the majority of the remaining cases were also PAH.

CONCLUSIONS

The cases analyzed in our study indicate that pulmonary hypertension can be one explanation for the reported heart failure of scurvy patients in the early literature. It would seem sensible to measure plasma vitamin C levels of patients with PH and examine the effects of vitamin C administration.

Biochemical Changes in Cardiopulmonary Bypass in Cardiac Surgery: New Insights

Patients undergoing coronary revascularization with extracorporeal circulation or cardiopulmonary bypass (CPB) may develop several biochemical changes in the microcirculation that lead to a systemic inflammatory response. Surgical incision, post-CPB reperfusion injury and blood contact with non-endothelial membranes can activate inflammatory signaling pathways that lead to the production and activation of inflammatory cells, with cytokine production and oxidative stress. This inflammatory storm can cause damage to vital organs, especially the heart, and thus lead to complications in the postoperative period. In addition to the organic pathophysiology during and after the period of exposure to extracorporeal circulation, this review addresses new perspectives for intraoperative treatment and management that may lead to a reduction in this inflammatory storm and thereby improve the prognosis and possibly reduce the mortality of these patients.

Risk of Hypovitaminosis and Vitamin C Deficiency in Pediatric Patients Undergoing Cardiopulmonary Bypass

Vitamin C levels are known rapidly decrease in adult critical illness. Vitamin C scavenges free radicals, provides critical protection of the endothelial barrier, and improves endothelial responsiveness to catecholamines. Children with congenital heart disease and undergoing cardiac surgery might be at increased risk for low circulating vitamin C levels. A prospective single-center observational study investigated perioperative changes in vitamin C levels in critically ill Children who underwent congenital heart surgery using CPB. Vitamin C serum levels were collected preoperatively and postoperatively (upon admission to the ICU, 24 and 72 h). Linear mixed-effect model was used to estimate mean circulating concentration of vitamin C and to estimate changes in concentration over time. Primary outcome was change in circulating levels of vitamin C before and after CPB. Secondary outcomes were hospital length of stay (LOS), acute kidney injury (AKI), and illness severity. Forty-one patients with a median age of 4.5 [interquartile range (IQR) 2.6-65.6] months at the time of surgery were consented and enrolled. Median CPB duration was 130 [90-175] minutes, and hospital LOS was 9.1 [5.2-19] days. Mean vitamin C levels (μmol/L) before CPB, at PICU admission, 24 h, and 72 h were 82.0 (95% CI 73.4-90.7), 53.4 (95% CI 44.6,62.0), 55.1 (95% CI 46.3,63.8), and 59.2 (95% CI 50.3,68.1), respectively. Upon postoperative admission to the PICU, vitamin C levels decreased by 28.7 (95% CI 20.6-36.8; p < 0.001) μmol/L, whereas levels at 24 and 72 h recovered and did not differ substantially from concentrations reported upon PICU admission (p > 0.15). Changes in vitamin C concentration were not associated with CPB time, STAT mortality category, age, or PIM3. Three patients had post-CPB hypovitaminosis C or vitamin C deficiency. Reduction in vitamin C levels was not associated with hospital LOS (p = 0.673). A 25 μmol/L decrease in vitamin C levels upon PICU admission was associated with developing AKI (aOR = 3.65; 95% CI 1.01-18.0, p = 0.049). Pediatric patients undergoing cardiac surgery with CPB showed decreased vitamin C levels during the immediate postoperative period. Effects of hypovitaminosis C and vitamin C deficiency in this population remain unclear.

Vasoplegic Syndrome and Anaesthesia: A Narrative Review

Vasoplegic syndrome (VS) is defined as low systemic vascular resistance, normal or high cardiac output, and resistant hypotension unresponsive to vasopressor agents and intravenous volume. VS is a frequently encountered complication in cardiovascular and transplantation surgery, burns, trauma, pancreatitis, and sepsis. The basis of the pathophysiology is associated with an imbalance of vasodilator and vasoconstrictive structure in vascular smooth muscle cells and is highly complex. The pathogenesis of VS has several mechanisms, including overproduction of iNO, stimulation of ATP-dependent K+ channels and NF-κB, and vasopressin receptor 1A (V1A-receptor) down-regulation. Available treatments involve volume and inotropes administration, vasopressin, methylene blue, hydroxocobalamin, Ca++, vitamin C, and thiamine, and should also restore vascular tone and improve vasoplegia. Other treatments could include angiotensin II, corticosteroids, NF-κB inhibitor, ATP-dependent K+ channel blocker, indigo carmine, and hyperbaric oxygen therapy. Despite modern advances in treatment, the mortality rate is still 30-50%. It is challenging for an anaesthesiologist to consider this syndrome's diagnosis and manage its treatment. Our review aims to review the diagnosis, predisposing factors, pathophysiology, treatment, and anaesthesia approach of VS during anaesthesia and to suggest a treatment algorithm.

Vasoplegia: A Review

Vasoplegia is a condition characterized by persistent low systemic vascular resistance despite a normal or high cardiac index, resulting in profound and uncontrolled vasodilation. Vasoplegia may occur due to various conditions, including cardiac failure, sepsis, and post-cardiac surgery. In the cardiac cohort, multiple risk factors for vasoplegia have been identified. Several factors contribute to the pathophysiology of this condition, and various mechanisms have been proposed, including nitric oxide, adenosine, prostanoids, endothelins, the renin-angiotensin-aldosterone system, and hydrogen sulfide. Early identification and prompt management of vasoplegia is crucial to prevent development of shock. This review expands upon the different vasopressors used in management of vasoplegia, including catecholamines such as norepinephrine, dopamine, epinephrine, phenylephrine, and other agents including vasopressin, methylene blue, angiotensin II, hydroxocobalamin, vitamin C, thiamine, and corticosteroids (ie, hydrocortisone). It also emphasizes the importance of conducting further research and making advancements in treatment regimens for vasoplegia.

Vasoplegic syndrome in patients undergoing heart transplantation

Objectives

To summarize the risk factors, onset time, and treatment of vasoplegic syndrome in patients undergoing heart transplantation.

Methods

The PubMed, OVID, CNKI, VIP, and WANFANG databases were searched using the terms "vasoplegic syndrome," "vasoplegia," "vasodilatory shock," and "heart transplant*," to identify eligible studies. Data on patient characteristics, vasoplegic syndrome manifestation, perioperative management, and clinical outcomes were extracted and analyzed.

Results

Nine studies enrolling 12 patients (aged from 7 to 69 years) were included. Nine (75%) patients had nonischemic cardiomyopathy, and three (25%) patients had ischemic cardiomyopathy. The onset time of vasoplegic syndrome varied from intraoperatively to 2 weeks postoperatively. Nine (75%) patients developed various complications. All patients were insensitive to vasoactive agents.

Conclusions

Vasoplegic syndrome can occur at any time during the perioperative period of heart tranplantation, especially after the discontinuation of bypass. Methylene blue, angiotensin II, ascorbic acid, and hydroxocobalamin have been used to treat refractory vasoplegic syndrome.

Review of Postoperative Care for Heart Transplant Recipients

The early postoperative management strategies after heart transplantation include optimizing the function of the denervated heart, correcting the causes of hemodynamic instability, and initiating and maintaining immunosuppressive therapy, allograft rejection surveillance, and prophylaxis against infections caused by immunosuppression. The course of postoperative support is influenced by the quality of allograft myocardial protection prior to implantation and reperfusion, donor-recipient heart size matching, surgical technique of orthotopic heart transplantation, and patient factors (eg, preoperative condition, immunologic compatibility, postoperative vasomotor tone, severity and reversibility of pulmonary vascular hypertension, pulmonary function, mediastinal blood loss, and end-organ perfusion). This review provides an overview of the early postoperative care of recipients and includes a brief description of the surgical techniques for orthotopic heart transplantation.

Clinical management of postcardiotomy shock in adults

Postcardiotomy cardiogenic shock represents the most serious expression of low cardiac output syndrome after cardiac surgery. Although infrequent, it is a relevant condition due to its specific and complex pathophysiology and important morbidity-mortality. The diagnosis requires a high index of suspicion and multimodal hemodynamic monitoring, where echocardiography and the pulmonary arterial catheter play a main role. Early and multidisciplinary management should focus on the management of postoperative or mechanical complications and the optimization of determinants of cardiac output through fluid therapy or diuretic treatments, inotropic drugs and vasopressors/vasodilators and, in the absence of a response, early mechanical circulatory support. The aim of this paper is to review and update the pathophysiology, diagnosis and management of postcardiotomy cardiogenic shock.

Vasoplegic syndrome after cardiovascular surgery: A review of pathophysiology and outcome-oriented therapeutic management

BACKGROUND

Vasoplegic syndrome (VPS) is defined as systemic hypotension due to profound vasodilatation and loss of systemic vascular resistance (SVR), despite normal or increased cardiac index, and characterized by inadequate response to standard doses of vasopressors, and increased morbidity and mortality. It occurs in 9%-44% of cardiac surgery patients after cardiopulmonary bypass (CPB). The underlying pathophysiology following CPB consists of resistance to vasopressors (inactivation of Ca²⁺ voltage gated channels) on the one hand and excessive activation of vasodilators (SIRS, iNOS, and low AVP) on the other. Use of angiotensin-converting enzyme inhibitor (ACE-I), calcium channel blockers, amiodarone, heparin, low cardiac reserve (EF < 35%), symptomatic congestive heart failure, and diabetes mellitus are the perioperative risk factors for VPS after cardiac surgery in adults. Till date, there is no consensus about the outcome-oriented therapeutic management of VPS. Vasopressors such as norepinephrine (NE; 0.025-0.2 µg/kg/min) and vasopressin (0.06 U/min or 6 U/h median dose) are the first choice for the treatment. The adjuvant therapy (hydrocortisone, calcium, vitamin C, and thiamine) and rescue therapy (methylene blue [MB] and hydroxocobalamin) are also considered when perfusion goals (meanarterial pressure [MAP] > 60-70 mmHg) are not achieved with nor-epinephrine and/or vasopressin.

AIMS

The aims of this systematic review are to collect all the clinically relevant data to describe the VPS, its potential risk factors, pathophysiology after CPB, and to assess the efficacy, safety, and outcome of the therapeutic management with catecholamine and non-catecholamine vasopressors employed for refractory vasoplegia after cardiac surgery. Also, to elucidate the current and practical approach for management of VPS after cardiac surgery.

MATERIAL AND METHODS

"PubMed," "Google," and "Medline" weresearched, and over 150 recent relevant articles including RCTs, clinical studies, meta-analysis, reviews, case reports, case series and Cochrane data were analyzed for this systematic review. The filter was applied specificallyusing key words like VPS after cardiac surgery, perioperative VPS following CPB, morbidity, and mortality in VPS after cardiac surgery, vasopressors for VPS that improve outcomes, VPS after valve surgery, VPS after CABG surgery, VPS following complex congenital cardiac anomalies corrective surgery, rescue therapy for VPS, adjuvant therapy for VPS, definition of VPS, outcome in VPS after cardiac surgery, etiopathology of VPS following CPB. This review did not require any ethical approval or consent from the patients.

RESULTS

Despite the recent advances in therapy, the mortality remains as high as 30%-50%. NE has been recommended the most frequent used vasopressor for VPS. It restores and maintain the MAP and provides the outcome benefits. Vasopressin rescue therapy is an alternative approach, if catecholamines and fluid infusions fail to improve hemodynamics. It effectively increases vascular tone and lowers CO, and significantly decreases the 30 days mortality. Hence, suggested a first-line vasopressor agent in postcardiac surgery VPS. Terlipressin (1.3μg/kg/h), a longer acting and more specific vasoconstrictor prevents the development of VPS after CPB in patients treated with ACE-I. MB significantly reduces morbidity and mortality of VPS. The Preoperative MB (1%, 2mg/kg/30min, 1h before surgery) administration in high risk (on ACE-I) patients for VPS undergoing CABG surgery, provides 100% protection against VPS, and early of MB significantly reduces operative mortality, and recommended as a rescue therapy for VPS. Hydroxocobalamin (5 g) has been recommended as a rescue agent in VPS refractory to multiple vasopressors. A combination of ascorbic acid (6 g), hydrocortisone (200 mg/day), and thiamine (400 mg/day) as an adjuvant therapy significantly reduces the vasopressors requirement, and provides mortality and morbidity benefits.

CONCLUSION

Currently, the VPS is frequently encountered (9%-40%) in cardiac surgical patients with predisposing patient-specific risk factors and combined with inflammatory response to CPB. Multidrug therapy (NE, MB, AVP, ATII, terlipressin, hydroxocobalamin) targeting multiple receptor systems is recommended in refractory VPS. A combination of high dosage of ascorbic acid, hydrocortisone and thiamine has been used successfully as adjunctive therapyto restore the MAP. We also advocate for the early use of multiagent vasopressors therapy and catecholamine sparing adjunctive agents to restore the systemic perfusion pressure with a goal of preventing the progressive refractory VPS.

Ascorbic Acid in the Acute Care Setting

Ascorbic acid (AA) is an essential nutrient with many physiologic roles not limited to the prevention of scurvy. Beyond its role as a supplement, it has gained popularity in the acute care setting as an inexpensive medication for a variety of conditions. Because of limitations with absorption of oral formulations and reduced serum concentrations observed in acute illness, intravenous (IV) administration, and higher doses, may be needed to produce the desired serum concentrations for a particular indication. Following a PubMed search, we reviewed published studies relevant to AA in the acute care setting and summarized the results in a narrative review. In the acute care setting, AA may be used for improved wound healing, improved organ function in sepsis and acute respiratory distress syndrome, faster resolution of vasoplegic shock after cardiac surgery, reduction of resuscitative fluids in severe burn injury, and as an adjunctive analgesic, among other uses. Each indication differs in its level of evidence supporting exogenous administration of AA, but overall, AA was not commonly associated with adverse effects in the identified studies. Use of AA remains an active area of clinical investigation for various indications in the acute care patient population.

Treatment With Angiotensin II Is Associated With Rapid Blood Pressure Response and Vasopressor Sparing in Patients With Vasoplegia After Cardiac Surgery: A Post-Hoc Analysis of Angiotensin II for the Treatment of High-Output Shock (ATHOS-3) Study

OBJECTIVE

The present study investigated outcomes in patients with vasoplegia after cardiac surgery treated with angiotensin II plus standard-of-care vasopressors. Vasoplegia is a common complication in cardiac surgery with cardiopulmonary bypass and is associated with significant morbidity and mortality. Approximately 250,000 cardiac surgeries with cardiopulmonary bypass are performed in the United States annually, with vasoplegia occurring in 20%to-27% of patients.

DESIGN

Post-hoc analysis of the Angiotensin II for the Treatment of High-Output Shock (ATHOS-3) study.

SETTING

Multicenter, multinational study.

PARTICIPANTS

Sixteen patients with vasoplegia after cardiac surgery with cardiopulmonary bypass were enrolled.

INTERVENTIONS

Angiotensin II plus standard-of-care vasopressors (n = 9) compared with placebo plus standard-of-care vasopressors (n = 7).

MEASUREMENTS AND MAIN RESULTS

The primary endpoint was mean arterial pressure response (mean arterial pressure ≥75 mmHg or an increase from baseline of ≥10 mmHg at hour 3 without an increase in the dose of standard-of-care vasopressors). Vasopressor sparing and safety also were assessed. Mean arterial pressure response was achieved in 8 (88.9%) patients in the angiotensin II group compared with 0 (0%) patients in the placebo group (p = 0.0021). At hour 12, the median standard-of-care vasopressor dose had decreased from baseline by 76.5% in the angiotensin II group compared with an increase of 7.8% in the placebo group (p = 0.0013). No venous or arterial thrombotic events were reported.

CONCLUSION

Patients with vasoplegia after cardiac surgery with cardiopulmonary bypass rapidly responded to angiotensin II, permitting significant vasopressor sparing.

Vasoplegia after cardiopulmonary bypass: A narrative review of pathophysiology and emerging targeted therapies

Cardiovascular disease remains the leading cause of death in the United States, and cardiopulmonary bypass is a cornerstone in the surgical management of many related disease states. Pathophysiologic changes associated both with extracorporeal circulation and shock can beget a syndrome of low systemic vascular resistance paired with relatively preserved cardiac output, termed vasoplegia. While increased vasopressor requirements accompany vasoplegia, related pathophysiologic mechanisms may also lead to true catecholamine resistance, which is associated with further heightened mortality. The introduction of a second non-catecholamine vasopressor, angiotensin II, and non-specific nitric oxide scavengers offers potential means by which to manage this challenging phenomenon. This narrative review addresses both the definition, risk factors, and pathophysiology of vasoplegia and potential therapeutic interventions.

Vasoplegic syndrome following cardiothoracic surgery-review of pathophysiology and update of treatment options

Vasoplegic syndrome is a common occurrence following cardiothoracic surgery and is characterized as a high-output shock state with poor systemic vascular resistance. The pathophysiology is complex and includes dysregulation of vasodilatory and vasoconstrictive properties of smooth vascular muscle cells. Specific bypass machine and patient factors play key roles in occurrence. Research into treatment of this syndrome is limited and extrapolated primarily from that pertaining to septic shock, but is evolving with the expanded use of catecholamine-sparing agents. Recent reports demonstrate potential benefit in novel treatment options, but large clinical trials are needed to confirm.

Vasoplegia During Cardiopulmonary Bypass: Current Literature and Rescue Therapy Options

Vasoplegia syndrome in the cardiac surgical intensive care unit and postoperative period has been an area of interest to clinicians because of its prevalence and effects on morbidity and mortality. However, there is a paucity of evidence regarding the treatment of vasoplegia syndrome during cardiopulmonary bypass (on-CPB VS). This review aims to detail the incidence, outcomes, and possible treatment options for patients who develop vasoplegia during bypass. The pharmacologic rescue agents discussed are used in cases in which vasoplegia during CPB is refractory to standard catecholamine agents, such as norepinephrine, epinephrine, and phenylephrine. Methods to improve vasoplegia during CPB can be both pharmacologic and nonpharmacologic. In particular, optimization of CPB parameters plays an important nonpharmacologic role in vasoplegia during CPB. Pharmacologic agents that have been demonstrated as being effective in vasoplegia include vasopressin, terlipressin, methylene blue, hydroxocobalamin, angiotensin II (Giapreza), vitamin C, flurbiprofen (Ropion), and hydrocortisone. Although these agents have not been specifically evaluated for vasoplegia during CPB, they have shown signs of effectiveness for vasoplegia postoperatively to varying degrees. Understanding the evidence for, dosing, and side effects of these agents is crucial for cardiac anesthesiologists when treating vasoplegia during CPB bypass.