Gloria Kai Yan Tang, Intensive Care Unit, Queen Mary Hospital, Hong Kong
Editor's note: Congratulations to Dr Tang who passed the CCM Exit Exam in May 2009!
Background:
B-type natriuretic peptide (BNP) has been investigated extensively as a marker of acute heart failure. It can also be raised in conditions with compromised myocardial reserve. Oesophagectomy is a complex operation with high morbidity with cardiopulmonary and surgical complications. This study aims to investigate the prognostic value of BNP in patients undergoing oesophagectomy for carcinoma of the oesophagus or cardia.
Methods:
In this prospective, single-blinded observational study conducted between February 2008 and February 2009, patients undergoing oesophagectomy for carcinoma of the oesophagus or cardia were recruited. The BNP was checked pre-operatively and subsequently on day 1 and day 3 post-operatively. The cardiac function was assessed by measurement of left ventricular systolic function by transthoracic echocardiogram on day 1 or day 2 post-operation. The fluid status was assessed by the haemodynamic parameters, the fluid balance and the serum creatinine. These values were measured over 3 days post-operation. The medical and surgical adverse events were recorded.
The B-type natriuretic peptide (BNP) profiles were compared with the presence of adverse events post-oesophagectomy using the Chi-square test or Fisher’s exact test. The fluid status, echocardiogram finding, and serum creatinine were correlated with the BNP levels using non-parametric analysis of Spearman’s correlation. The secondary endpoints included the length of stay in the Intensive Care Unit and the length of hospital stay.
Results:
30 patients were recruited in this study. A BNP level of ≥ 100pg/ml was taken to be elevated. The baseline BNP level (113pg/ml +/- 205 versus 26.89 +/- 14.47) was found to have an insignificant trend to be higher in patients having any adverse events post-oesophagectomy (p=0.073). The BNP level on day 3 post-operation was significantly raised in patients with adverse events (p=0.014). In particular, atrial fibrillation was found to be associated with a higher BNP level on day 3 post-operation (p=0.044). Moreover, a high BNP level of ≥ 100pg/ml on day 3 post-operation also correlated with a more prolonged ICU stay (p=0.006, Mann-Whitney test). The median stay of ICU in this group of patient was 4 days, compared with 2 days in the group of patients with BNP < 100pg/ml.
The serum creatinine, the daily and overall fluid status, and the cardiac function as assessed by echocardiogram were found to have no correlation with the level of BNP. There was also no correlation found between the BNP level and the length of stay in hospital.
Conclusion:
In view of the complexity and high morbidity of oesophagectomy, it would be invaluable to be able to predict and be alerted to post-operative complications. B-type natriuretic peptide was shown in this study to have predictive value for adverse events post-oesophagectomy. The cutoff of an elevated BNP level will need to be verified with further studies. Nonetheless, it can be concluded that BNP has prognostic implications post-oesophgectomy, and can be an invaluable tool for the peri-operative management of patients undergoing oesophagectomy.
References
Lorenzo E, Law S, Wong KH. The influence of technical complications on postoperative outcome and survival after esophagectomy. Annals of Surgical Oncology 2006; 13(4): 557-564.
2 Law S, Wong J, Murthy S. Atrial fibrillation after oesophagectomy is a marker for postoperative morbidity and mortality. The Journal of Thoracic and Cardiovascular Surgery. October 2003; 126(4): 1162-1167.
3 Takashi K, Tadanori M, Yoshihiko K. Fluid management and postoperative respiratory disturbances in patients with transthoracic esophagectomy for carinoma. Journal of Clinical Anaesthesia 2002; 14: 252-256.
4 Hosoda K, Nakao K, Mukoyama M. Expression of brain natriuretic peptide gene in human heart. Production in the ventricle. Hypertension 1991; 17: 1152-55.
5 Wiese S, Breyer T, Dragu A. Gene expression of brain natriuretic peptide in isolated atrial and ventricular human myocardium: Influence of angiotensin II and diastolic fibre length. Circulation 2000; 102: 3074-3079.
6 Maisel AS, Krishnaswamy P, Nowak RM. Rapid measurement of B-type natriuretic peptide in the emergency diagnosis of heart failure. New England Journal of Medicine 2002; 347: 161-167.
7 Maeda K, Tsutamoto T, Wada A et al. Plasma brain natriuretic peptide as a biochemical maker of left ventricular end-diastolic pressure in patients with symptomatic left ventricular dysfunction. American Heart Journal 1998; 135: 825-832.
8 Thygesen K, Alpert J, White H. Universal definition of myocardial infarction. Circulation 2007; 116: 2634-2653.
9 Duggan, MB, Kavanagh, B. Pulmonary atelectasis: a pathogenic perioperative entity. Anesthesiology April 2005; 102(4): 838-854.
10 Garner JS, Jarvis WR, Emori TG, Horan TC, Hughes JM. CDC definitions for nosocomial infections 1988. Amerian Journal of Infection Control; 16: 28-40.
11 De Bold AJ, Borenstein HB, Veress AT. A rapid and potent natriureitc response to intravenous injection of atrial myocardial extract in rats. Life Science 1981; 28: 89-94.
12 Felker GM, Petersen JW, Mark DB. Natriuretic peptides in the diagnosis and management of heart failure. Canadian Medical Association Journal. Sept 2006; 175(6): 611-617.
13 Phua J, Lim TK, Lee KH. B-type natriuretic peptide: issues for the intensivist and pulmonologist. Critical Care Medicine. 2005; 33: 2094-2103.
14 Yoshimura M, Yasue H, Okamura K, et al. Different secretion pattern of atrial natriuretic peptide and brain natriuretic peptide in patients with congestive heart failure. Circulation 1993; 87: 464-469.
15 Maisel AS, Koon J, Krishnaswamy P. Utility of B-type natriuretic peptide as a rapid, point-of-care test for screening patients undergoing echocardiography to determine left ventricular dysfunction. American Heart Journal 2001; 141(3): 367-374.
16 Omland T. Advances in congestive heart failure management in the intensive care unit: B-type natriuretic peptides in evaluation of heart failure. Critical Care Medicine 2008; 36(1): S17-27.
17 Friese RS, Dineen S, Jennings A. Serum B-type natriuretic peptide: a marker of fluid resuscitiation after injury? The Journal of Trauma Injury, Infection and Critical Care. 2007; 62(6): 1346-1351.
18 Cuthbertson BH, Patel RR, Croal BL et al. B-type natriuretic peptide and the prediction of outcome in patients admitted to intensive care. Anaesthesia 2005; 60: 16-21.
19 Tung RH, Garcia C, Morss AM et al. Utility of B-type natriuretic peptide for the evaluation of intensive care unit shock. Critical Care Medicine 2004; 32(9): 1643-1647.
20 Dessap AM, Brochard L. B-type natriuretic peptide and weaning from mechanical ventilation. Clinical Pulmonary Medicine 2009; 16(2): 89-94.
21 McLean AS, Huang SJ, Nalos M, Tang B. The confounding effects of age, gender, serum creatinine, and electrolyte concentrations on plasma B-type natriuretic peptide concentrations in critically ill patients. Critical Care Medicine 2003; 31(11): 2611-2618.
22 Terasako K. Perioperative plasma concentrations of atrial and brain natriuretic peptides in patients undergoing hip arthroplasty. Anaesthesia and Intensive Care 2002; 30(5): 588-590.
23 Medical Research Council Oesophageal Cancer Working Party. Surgical resection with or without preoperative chemotherapy in oesophageal cancer: a randomized controlled trial. Lancet 2002; 359: 1727-1733.
24 Whooley BP, Law S, Alexandrou A, et al. Critical appraisal of the significance of the intrathoracic anastomotic leakage after oesophagectomy for cancer. American Journal of Surgery 2001; 181: 198-203.
25 Law S, Wong KH, Kwok KA, Chu KM, Wong J. Predictive factors for postoperative pulmonary complications and mortality after oesophagectomy for cancer. Annals of Surgery 2004; 240(5); 791-800.
26 Redfield MM, Rodeheffer RJ, Jacobsen SJ, et al. Plasma brain natriuretic peptide to detect preclinical ventricular systolic or diastolic dysfunction: a community-based study. Circulation 2004; 109: 3176-3181.