a 69-year - old , 65 kg , american society of anesthesiologists physical status ii woman was scheduled to undergo open reduction and internal fixation for a right - sided ankle fracture due to a pedestrian traffic accident .
the electrocardiogram ( ecg ) was unremarkable , but laboratory evaluation revealed low hemoglobin ( 9.2 g / dl ) and prolongation of prothrombin time 15.8 sec ( 74% , inr 1.23 ) , and chest computed tomography showed bilateral pleural effusion .
echocardiography revealed a good ejection fraction ( 60% ) , mild biventricular hypertrophy , and pulmonary hypertension ( 40 mmhg ) . in the previous month , she received 2 surgical operations ( closed reduction of left - sided intertrochanteric fracture under general anesthesia and the debridement and irrigation of lower extremity under epidural anesthesia ) .
for the surgery resulting in af , the patient received 0.5 mg atropine and 2 mg midazolam i m as premedication 30 min before surgery . upon arrival in the operating room ,
an ecg was recorded and automated bp cuff and pulse oximeter ( spo2 ) monitors were applied . the patient 's preoperative blood pressure ( bp )
was 140/70 mmhg and pre - operative heart rate ( hr ) was 82 beats / min with a sinus rhythm , and spo2 was 95% .
loss of resistance was used to identify the epidural space in the left lateral decubitus position .
an epidural catheter was inserted through a needle and 3 ml lidocaine 2% were administered as a test dose , without complications . via epidural catheter , 9 ml lidocaine 2% and 50 g fentanyl were given for epidural analgesia .
the patient received 500 ml ringer 's solution before and after receiving epidural injection . at fifty minutes after epidural drug injection
, the analgesia was obtained up to inguinal area by pinprick test and the bp slowly decreased to 110/70 mmhg with hr maintaining 85 beats / min .
twenty minutes after epidural injection , she was sterilized with disinfectant such as betadine , alcohol for the right - sided leg , but she complained about buttock pain by running down of disinfectant in leg - raising position . at that time , the patient 's bp was steady at 110/65 mmhg but her hr abruptly increased to 185 beats / min with a paroxysmal af pattern ( fig .
1 ) . this paroxysmal af persisted for 30 min , despite injection of esmolol 30 and digoxin 0.25 mg iv .
we thought that the injected dose of epidural anesthetics was not sufficient for pain relief in the leg due to the massive crushing injury of the patient 's lower extremity .
the patient was pre - oxygenated , induced with 5 ml propofol 2% and 0.05 g / kg / min remifentanil infusion without muscle relaxant , and was easily mask - ventilated .
anesthesia was maintained using 2 - 3 ml / hr propofol 2% , 0.05 g / kg / min remifentanil and 4 l / min oxygen immediately after intubation .
five minutes after induction , the patient 's bp decreased abruptly to 60/40 mmhg while hr continued to be high at 175 beats / min with af pattern .
we decided to cancel the operation because the paroxysmal af had continued and the patient 's vital signs were unstable .
all surgical drapes and tourniquets were removed from the operative site , and phenylephrine infusion 0.1 - 0.5 g / kg / min was started . at that time
, the bp increased to 115/66 mmhg and hr declined to 125 beats / min but the af pattern sustained .
the patient regained alert mentality and had bp of 110/70 mmhg and a hr of 120 beats / min .
the duration of anesthesia was 80 mins , a total of 600 ml of hartmann solution was injected , and urine output was 190 ml .
the patient was transferred to the intensive care unit and was prescribed diltiazem 30 mg bid ( a calcium channel blocker ) and fraxiparine during following 4 days for thromboembolism prophylaxis . after arriving at the icu , the patient 's hr gradually decreased and the ecg showed normal sinus rhythm with a hr of 81 beats / min .
echocardiography revealed left ventricular hypertrophy , pulmonary hypertension ( 36 mmhg ) and normal left ventricular function . on the fourth days after the af event , the patient underwent surgery for a right - sided intertrochanteric fracture under general anesthesia without any events or problems .
the incidence of perioperative af in noncardiac , nonthoracic surgical patients is 0.37% , but most frequently occurs within 3 days of surgery .
perioperative af is often associated with significant morbidity ( 12% of af patients ) , longer hospital stays due to continued af ( 16% of af patients ) , and increased costs related to the af .
most instances of af are associated with cardiac and some pulmonary diseases as well as metabolic , toxic , endocrine , or genetic abnormalities , and some af events are likely related autonomic changes and inflammatory responses [ 2 - 6 ] .
these aggravating factor for af are ( i ) surgically induced trauma ( autonomic denervation , cannulation of atria ) , ( ii ) high adrenergic tone ( elevated hr before surgery ) , ( iii ) inflammatory response ( postoperative state , c - reactive protein [ crp ] , interleukin-6 ) , and ( iv ) tachycardia ( remodeling of the atria , ionic channel changes ) . our patient had four aggravation factors ( autonomic denervation by epidural anesthesia , high adrenergic tone and tachycardia by light anesthesia , and increased crp due to inflammation ) .
classification of af subtypes is ' paroxysmal ( within 7 days ) ' , ' persistent ( over 7 days ) ' , and ' permanent ' according to the duration of the episode .
patients initially presenting with paroxysmal af often progress to longer , non - self - terminating bouts .
almost half of the patients with paroxysmal af have no obvious clinical cause ( lone or idiopathic af ) .
af without underlying organic abnormalities occurs more often against the background of parasympathetic predominance , whereas af with structural heart disease usually occurs in a sympathetic setting .
af that is initially responsive to pharmacological treatment or electrical cardioversion tends to become resistant and then can not be converted to sinus rhythm .
effective prevention is essential in managing this arrhythmia whose occurrence is widespread , progression is relentless , and morbidity and mortality are significant . in our case ,
a history of frequent operations , inflammation , a state of inadequate analgesia by epidural anesthesia , and surgery - related anxiety may have induced the paroxysmal af observed .
first , the patient received a 3rd operation at postoperative day 2 following the 2nd operation .
second , inflammation caused by the crushing injury of the patient 's lower extremities was evident as her crp level had increased to 254 - 449 mg / l which could increase the possibility of af development .
third , the sympathetic and parasympathetic systems are associated with af , but the increase in acetylcholine by parasympathetic stimulation is known as the main factor involved in the development of af rather than enhanced vagal or sympathetic drive alone .
.   reported on the effects of beta - adrenergic and cholinergic stimulation or blockade on paroxysmal af by adrenaline or acetylcholine perfusion to the sinus node artery in anesthetized open - chest dogs .
adrenaline and acetylcholine induce af in 17% and 100% of dogs , respectively , and the adrenergic tone facilitated the initiation of cholinergically mediated af .
their study indicated that although both autonomic systems play a role in the development of af , cholinergic stimulation is the primary factor for paroxysmal af initiation while adrenergic tone facilitates the initiation and maintenance of cholinergically mediated af . in our case , parasympathetic predominance induced by epidural sympathetic blockade might induce the development of af , and the increase in adrenergic activity from pain due to insufficient anesthesia facilitated the initiation and maintenance of af . in a recent study , a primary role of cholinergic stimulation in af generation was made evident by revealing an abrupt shift toward vagal predominance immediately before af onset in patients with paroxysmal af .
lastly , approximately one third of af patients have elevated levels of depression and anxiety .
in our case , the preoperative surgery - related emotional stress of the patient facilitated the development of af .
generally , the purposes of af treatment are ( i ) to control hr , ( ii ) to maintain of sinus rhythm , and ( iii ) to decrease the thromboembolism risk .
the drugs used for hr control are -blocking drugs , calcium channel blockers , and digoxin , and electrical cardioversion is used to treat hemodynamically unstable af . in our case , esmolol 30 mg and digoxin 0.25 mg were used , but af continued .
the combined use of digoxin and esmolol is usually effective in the control of hr .
the onset of digoxin takes up to 30 min and the peak effect is obtained at 1 - 4 hr . by the delayed effect of this drug , af slowly disappeared .
when af persists without a conversion of sinus rhythm , the potential for thromboembolism develops within 48 hr . if af is seen to cause a greater risk of stroke , then heparin must be used prophylactically .
once af is controlled in the perioperative period , the anesthesiologist is then faced with the dilemma of whether to proceed or delay the surgery .
although the incidence of newly developed atrial arrhythmias associated with acute myocardial infarction , pulmonary embolism , pericarditis , or thyrotoxicosis is less than 1% , physicians need to rule out significant structural heart disease using transthoracic echocardiogram in making their decision on how to proceed . in conclusion ,
the proper preoperative prevention and intraoperative treatment are needed in patients at high risk for paroxysmal af .
 atrial fibrillation ( af ) is the most common sustained tachyarrhythmia , and occurs in organic heart disease such as rheumatic , atherosclerotic and hypertensive heart disease . in recent studies , 
 the sympathetic and parasympathetic nervous systems have been shown to have important roles in initiating paroxysmal af . 
 we report here a patient who developed paroxysmal af that might be a result of an imbalance of the sympathetic - parasympathetic systems due to epidural anesthesia , and that was potentiated by pain with inadequate analgesia . 
 a 69-year - old woman was scheduled for operation of a right - sided ankle fracture . 
 twenty minutes after epidural drug injection , paroxysmal af occurred . even after intravenous administration of esmolol and digoxin , af continued . 
 after transfer to the intensive care unit , her heart rate gradually decreased and af disappeared . during perioperative anesthetic management , the proper preoperative prevention and intraoperative treatment are needed in af high - risk patients . 
Case Report
Discussion