Ashwani K. Chhibber

Primary fibrinolysis during supraceliac aortic clamping

PURPOSE An increased incidence of bleeding complications has been observed after supraceliac aortic clamping (SCC). This study was performed to identify possible hemostatic abnormalities that contribute to this problem. METHODS A prospective cohort study over a 3-month period was performed by comparing hemostatic parameters in 10 consecutive patients who required elective SCC with those of eight concurrent randomly selected control subjects who required infrarenal clamping (IRC) for abdominal aortic reconstruction. Measures of coagulation, fibrinolysis, platelet function, temperature, hemodilution, and hepatic function were performed at selected times before, during, and after operation. RESULTS Aneurysm size, fibrinogen, D-dimers, prothrombin, partial thromboplastin time, platelet counts, bleeding times, hemodilution, and temperature were comparable in both groups. Patients in the SCC group, however, consistently developed a primary fibrinolytic state within 20 minutes after supraceliac clamping, reflected by significantly decreased euglobulin clot lysis times (ECLT; p < 0.0001), elevated tissue plasminogen activator (t-PA) levels (p < 0.0006), elevated t-PA-to-plasminogen activator inhibitor-1 ratios (p < 0.0001), and reduced alpha 2-antiplasmin levels (p < 0.002). SCC produced hepatocellular injury documented by elevations in both aspartate transaminase (p < 0.0001) and lactate dehydrogenase (p < 0.009). CONCLUSIONS SCC rapidly induces a primary fibrinolytic state manifested by increased circulating t-PA, reduced alpha 2-antiplasmin, and increased fibrinolytic activator-to-inhibitor ratios. These effects may be a result of hepatic hypoperfusion caused by SCC leading to insufficient clearance of t-PA. Antifibrinolytic agents may be of benefit if bleeding develops after aortic procedures that require supraceliac clamping.

Anesthesia care for adult live donor hepatectomy: Our experiences with 100 cases

A total of 100 patients who underwent elective lobar donor hepatectomy from 2000 to 2002 at the University of Rochester Medical Center were reviewed. Assessed clinical data were estimated blood loss, intraoperative central venous pressure (CVP), blood product and fluid administration, perioperative arterial blood gas tension and acid‐base state, metabolic status, perioperative serum levels of aspartate aminotransferase, alanine aminotransferase, prothrombin time, albumin, and lactate, procedure duration, and perioperative complications. All patients survived surgery, and the average duration of surgery (from skin incision to skin closure) was 615 ± 99.6 minutes. Mean blood loss was 549 ± 391 mL (range, 80‐2,500 mL), and only 4 patients required homologous blood transfusion. The intraoperative blood loss did not correlate with CVP values. A total of 72 patients received isotonic sodium bicarbonate solution, and their metabolic variables were superior to those of normal saline group patients (arterial pH, 7.35 ± 0.03 vs. 7.29 ± 0.07; base excess, −4.3 ± 2.4 vs. 7.3 ± 3.4; and serum bicarbonate level, 20.6 ± 2.2 vs. 18.6 ± 2.9). However, the better control of metabolic acidosis was not associated with serum lactate levels or other outcome measures. Maintaining the CVP < 5 mmHg was not associated with blood loss. Clinically significant anesthetic complications were severe metabolic acidosis, pneumothorax and respiratory insufficiency immediately following extubation in the operating room. In conclusion, placement of a thoracic epidural catheter delivering a local anesthetic in addition to intravenous (IV) patient‐controlled analgesia with opiates provided safe and effective pain control in most patients. Further prospective studies should shed a light on the optimal care of patients undergoing liver donor hepatic resection. Liver Transpl 13:537–542, 2007.

Effects of Anticholinergics on Postoperative Vomiting, Recovery, and Hospital Stay in Children Undergoing Tonsillectomy with or without Adenoidectomy

BACKGROUND Nausea and vomiting are the most frequent problems after minor ambulatory surgical procedures. The agents used to induce and maintain anesthesia may modify the incidence of emesis. When neuromuscular blockade is antagonized with anticholinesterases, atropine or glycopyrrolate is used commonly to prevent bradycardia and excessive oral secretions. This study was designed to evaluate the effect of atropine and glycopyrrolate on postoperative vomiting in children. METHODS Ninety-three patients undergoing tonsillectomy with or without adenoidectomy were studied. After inhalation induction of anesthesia with nitrous oxide, oxygen, and halothane, anesthesia was maintained with a nitrous oxide-oxygen mixture, halothane, morphine, and atracurium. Patients were randomized to receive, in a double-blinded manner, either 15 microg/kg atropine or 10 microg/kg glycopyrrolate with 60 microg/kg neostigmine to reverse neuromuscular blockade. Patient recovery, the incidence of postoperative emesis, antiemetic therapy, and the duration of postoperative hospital stay were assessed. RESULTS There were no significant differences in age, gender, weight, or discharge time from the postanesthesia care unit or the hospital between the groups. Twenty-four hours after operation, the incidence of vomiting in the atropine group (56%) was significantly less than in the glycopyrrolate group (81%; P<0.05). There was no significant difference between the atropine and glycopyrrolate groups in the number of patients who required antiemetics or additional analgesics. CONCLUSIONS In children undergoing tonsillectomy with or without adenoidectomy, reversal of neuromuscular blockade with atropine and neostigmine is associated with a lesser incidence of postoperative emesis compared with glycopyrrolate and neostigmine.

Penile block timing for postoperative analgesia of hypospadias repair in children

PURPOSE It has been well established that a dorsal penile nerve block immediately after surgery decreases postoperative pain in children undergoing hypospadias repair. However, to our knowledge the efficacy of a penile block immediately before versus immediately after surgery for postoperative pain control has not been previously studied in such children. MATERIALS AND METHODS We evaluated 98 healthy boys 6 months to 12 years old undergoing hypospadias repair. General anesthesia was induced and maintained in a standard fashion. Patients were randomly assigned to receive a penile block with the same total dose of bupivacaine at the completion of surgery, before the incision or before and at the completion of surgery. No other analgesic was administered intraoperatively. Pain was assessed using a modified objective pain-discomfort scale at 15 minutes, and 3, 12 and 24 hours after surgery. The number of doses of acetaminophen required to control postoperative pain was also recorded. RESULTS Pain scores were defined in a range of 0-no pain to 6-greatest pain. During recovery median pain scores in the 30, 36 and 32 boys who received a penile block after, before, and before and after surgery were 3, 1.5 and 0 at 15 minutes; 2.5, 1 and 0 at 3 hours; 3, 2 and 0 at 12 hours; and 1, 0 and 0 at 24 hours, respectively. There was no difference in acetaminophen doses required 15 minutes and 3 hours postoperatively in the 3 groups. By 12 hours after surgery the number of acetaminophen doses required for pain control was significantly lower in the before and after, and before groups than in the after group. By 24 hours boys in the before and after group required significantly fewer doses of analgesics than those in the after and before groups. There was no statistically significant difference between the after and before groups. CONCLUSIONS Two penile blocks performed at the beginning and conclusion of hypospadias repair, respectively, provide better postoperative pain control than 1 penile block done before or after surgery (p < 0.05). These patients require less analgesic than those who receive a penile block only before or only after surgery.

Use of esmolol to control bleeding and heart rate during electroconvulsive therapy in a patient with an intracranial aneurysm

Electroconvulsive therapy (ECT) is a commonly used treatment modality for patients with major affective disorders that are unresponsive to pharmacological therapy. While ECT has been shown to be a very safe treatment, it is associated with transient hemodynamic alterations, including hypertension, which are associated with an increased risk of rupture of an intracranial aneurysm. We describe our use of the ultrashort acting beta-blocker, esmolol, for blood-pressure control in a woman with known cerebral aneurysmal disease who required ECT for treatment of recurrent major depression.

Relationship between end-tidal and arterial carbon dioxide with laryngeal mask airways and endotracheal tubes in children.

The laryngeal mask airway (LMA) is a useful tool for securing the airway in adults and children and may be substituted for an endotracheal tube (ETT) in selected patients undergoing general anesthesia.The correlation between end-tidal and arterial carbon dioxide during controlled ventilation via LMA has not been reported in a within-patient design in pediatric patients. After induction of general anesthesia, 22 children had a LMA placed and mechanical ventilation initiated. After reaching steady-state end-tidal carbon dioxide (PETCO2), an arterial blood sample was obtained and the partial pressure of carbon dioxide (PaCO2) was measured. The LMA was then removed, the trachea was intubated, and identical ventilatory variables were resumed. After a stable PETCO2 was reestablished (minimum 5 min), a second PaCO2 was measured and the PETCO2 recorded. The mean PETCO2 and PaCO2 obtained during ventilation via the LMA were 37.7 +/- 3.31 and 41.9 +/- 9.09, respectively. The mean PETCO2 and PaCO2 obtained during ventilation via the ETT were 35.2 +/- 2.86 and 39.2 +/- 5.25, respectively. Analysis of differences between PaCO (2) and PETCO2 revealed a bias +/- precision of 4.0 +/- 3.42 and 4.2 +/- 3.66 with ventilation via ETT and LMA, respectively. The root mean square error was 0.85 for the ETT and 0.89 for the LMA. Our results indicate that in infants and children weighing more than 10 kg who are mechanically ventilated via the LMA PETCO2 is as accurate an indicator of PaCO2 as when ventilated via ETT. (Anesth Analg 1996;82:247-50)

Ephedrine-induced coronary artery vasospasm in a patient with prior cocaine use

A 42-yr-old male with peripheral vascular disease presented for a right femoral-popliteal bypass procedure. Despite lower extremity claudication, the patient worked lo-13 h daily at an automotive plant, assembling heavy machinery and pulling carts weighing up to 120 pounds. He denied chest pain, palpitations, or syncope. Although his arterial blood pressure during preoperative evaluation 5 days prior to surgery was 173155 mm Hg, he had no history of hypertension and multiple subsequent blood pressures were normotensive with a normal pulse pressure. He had a history of untreated glucose intolerance; a nonfasting preoperative blood glucose level was 132 mg/dL. He had smoked threefourths of a pack of cigarettes per day for 15 yr. He used cocaine almost daily many years ago, but claimed only monthly use over the last 10 yr and that he last used cocaine at a party 4 days prior to surgery. He was taking no medications. Electrocardiogram (ECG) revealed sinus bradycardia at 55 bpm. The patient desired spinal anesthesia. In the preanesthesia room, he received 4 mg of midazolam intravenously (IV). After infusing 700 mL IV of lactated Ringer’s solution, 15 mg of bupivacaine and 0.2 mg of preservative-free morphine were injected intrathecally at the L3-4 interspace. The patient was placed in the right lateral decubitus position for 5 min, and then placed supine with a sensory block to the T-6 dermatome. Arterial blood pressure decreased from 115 / 60 mm Hg to 88/40 mm Hg with an increase in heart rate from 65 to 70 bpm, and the patient complained of nausea. Ephedrine 10 mg was given IV. Approximately 30 s later, the patient

Torsade de Pointes During Orthotopic Liver Transplantation

The patient was a 53-kg, 57-yr-old woman with Child-Pugh grade C alcohol-induced end-stage liver disease who was referred for orthotopic liver transplantation. The patient had a 90 pack/yr smoking history, mild chronic obstructive pulmonary disease, and a previous gunshot wound to the abdomen. Medications included omeprazole, lactulose, spironolactone, furosemide, ipratroprium, and albuterol. Preoperative evaluation included an electrocardiogram (EKG) with sinus rhythm at 66 bpm, a large U wave in lead V,, and an unrecognized mildly prolonged QTc interval of 0.53 s (normal <0.45 s) with QTc dispersion of 66 ms (normal 20-50 ms). An EKG obtained 1 yr earlier was similar, with a QTc interval of 0.50 s and QTc dispersion of 84 ms. The patient denied syncope or palpitations and had no family history of prolonged QT or sudden death. The patient was referred to a cardiologist because of increased pulmonary artery pressures detected by echocardiography. Preoperative right and left heart catheterizations revealed no significant coronary artery disease, normal left ventricular systolic function, mild pulmonary hypertension (35/20 mm Hg; normal 15-30/4-12 mm Hg), mildly increased left heart filling pressures (pulmonary wedge pressure and left ventricular end-diastolic pressure 19 mm Hg; normal 5-12 mm Hg), and an increased cardiac index (6.4 L . min-* * mP2; normal 2.5-4.2 L * mir-’ * rn-‘). Anesthesia for liver transplantation was induced with thiopental and succinylcholine and maintained with air/ oxygen, isoflurane, remifentanil, and cisatracurium. The patient received magnesium 4 g IV to treat a serum magnesium level of 1.2 mEq/L (normal 1.3-1.9 mEq/L). The dissection

Comparison of end-tidal and arterial carbon dioxide in infants using laryngeal mask airway and endotracheal tube.

The laryngeal mask airway (LMA) has become a popular tool for airway management in selected adult and pediatric patients undergoing routine surgical procedures.The relationship between end-tidal and arterial carbon dioxide during controlled ventilation via the LMA in infants under 10 kg has not been reported. After induction of general anesthesia, the LMA was placed in 12 healthy infants and mechanical ventilation initiated. After maintaining steady-state level of end-tidal carbon dioxide (minimum 5 min), an arterial blood sample was obtained and end-tidal carbon dioxide level noted. The laryngeal mask was then removed, the trachea intubated, and mechanical ventilation resumed with initial ventilatory variables. After reaching a steady-state level of end-tidal carbon dioxide, a second arterial sample was obtained and end-tidal carbon dioxide level noted. The mean end-tidal carbon dioxide and arterial partial pressure of carbon dioxide obtained during ventilation were 42.2 +/- 7.9 and 47.1 +/- 11.0 (LMA) and 37.4 +/- 4.6 and 42.6 +/- 6.7 (endotracheal tube), respectively. Analysis of differences between partial pressure of carbon dioxide and end-tidal carbon dioxide using the Bland and Altman method revealed bias +/- precision of 4.9 +/- 3.9 and 5.3 +/- 3.2 with ventilation via the laryngeal mask and endotracheal tube. Our data indicate that, while ventilating infants under 10 kg with LMA, end-tidal carbon dioxide is an accurate indicator of arterial partial pressure of carbon dioxide. (Anesth Analg 1997;84:51-3)

Preoperative stress testing: new guidelines.

To date, there are no well controlled trials in the literature that demonstrate an outcome benefit using stress testing as a screening procedure before noncardiac surgery. Perioperative beta-blockade significantly decreases morbidity and mortality, and thus reduces any potential benefit stress testing may have in identifying patients who may advance to more invasive treatment. Preoperative percutaneous coronary intervention has unproven perioperative benefit, and coronary artery bypass graft carries risks that often offset the risk of noncardiac surgery. Unless an outcome benefit from cardiac testing and procedures can be demonstrated in a properly designed trial, their use should generally be restricted to situations in which symptoms or other cardiac findings warrant cardiac evaluation and treatment, regardless of upcoming surgery.