Major Intra-abdominal Surgery Research Articles

Rapid Saline Infusion Produces Hyperchloremic Acidosis in Patients Undergoing Gynecologic Surgery

SCHEINGRABER, STEFAN; REHM, MARKUS; SEHMISCH, CHRISTIANE; FINSTERER, UDILO Author Information

Cardiopulmonary Exercise Testing as a Screening Test for Perioperative Management of Major Surgery in the Elderly

To develop an integrated strategy for the identification and subsequent management of high-risk patients in order to reduce both morbidity and mortality. Prospective consecutive series in which all patients underwent cardiopulmonary exercise (CPX) testing. CPX laboratory and level 3 ICU and high-dependency unit (HDU) of a metropolitan teaching hospital. Five hundred forty-eight patients >60 years of age (or younger with known cardiopulmonary disease) scheduled for major intra-abdominal surgery. The patients were assigned to one of three management strategies (ICU, HDU, or ward) based on the anaerobic threshold (deltaT) and ECG evidence of myocardial ischemia as determined by CPX testing that was performed as part of the presurgery evaluation, and by the expected oxygen demand stress of the surgical procedure. Overall mortality was 3.9%. Forty-three percent of deaths were attributed to poor cardiopulmonary function, as detected preoperatively. There were no deaths related to cardiopulmonary complications in any patient deemed fit for major abdominal surgery and ward management, as determined by CPX testing. In elderly patients undergoing major intra-abdominal surgery, the AT, as determined by CPX testing, is an excellent predictor of mortality from cardiopulmonary causes in the postoperative period. Preoperative screening using CPX testing allowed the identification of high-risk patients and the appropriate selection of perioperative management.

No Evidence of Sevoflurane-Induced Renal Injury in Volunteers

No Evidence of Sevoflurane-Induced Renal Injury in Volunteers

Abdominal aortic aneurysm repair using the meadox/vanguard prosthesis: Indications, implantation technique, and results

The purpose of developing percutaneously placed endoluminal stent-grafts for the treatment of aortic aneurysms is to avoid major intra-abdominal surgery and related morbidity and mortality. To define its clinical utility, the authors prospectively studied polyester-covered nitinol stents for the treatment of infrarenal abdominal aortic aneurysms (AAAs). Since 1994, the authors implanted in a total of 228 patients nonbifurcated or bifurcated stent-grafts based on a self-expandable nitinol framework covered with a thin polyester fabric for the endovascular repair of infrarenal AAA. The patient cohort was divided into two subgroups: Group 1 (n = 120) consisted of patients treated with use of the original stent-graft; Group 2 (n = 108) comprised patients treated with the refined stent-graft. Preprocedural evaluation with precise determination of the length and diameter of the proximal neck and the common iliac arteries was based on spiral computed tomography, intra-arterial angiography, and magnetic resonance angiography. The initial technical success rates in patients of Group 1 presenting with a type A aneurysm (n = 9), and type B or C aneurysms (n = 111) were 78% and 82%, respectively. Minor and major complications, including one 30-day mortality, were observed in 14 patients (11.7%). With refinement of the polyester cover as a consequence from our initial experiences, we achieved in Group 2 for type A (n = 8), and type B or C aneurysms (n = 100) primary success rates of 100% and 97%, respectively. The rate of local and remote complications in this group was 6.5%. Based on our initial and mid-term results, endoluminal repair of infrarenal AAA with use of straight or bifurcated stent-grafts is a feasible alternative to conventional surgical repair associated with a low rate of morbidity and mortality.

Total-body oxygen consumption after isoflurane anesthesia: Effects of mild hypothermia and combined epidural-general anesthesia

Study Objectives: To determine the effects of epidural anesthesia and avoidance of intraoperative heat loss on the increase in total-body oxygen consumption in the immediate postoperative period after major intraabdominal surgery. Design: Prospective, randomized (with regard to temperature management) study. Setting: University medical center. Patients: 24 ASA physical status I, II, and III adults. Interventions: All patients received either isoflurane-nitrous oxide (N 2O)-opioid general anesthesia or combined epidural-general anesthesia; patients were randomly assigned to active intraoperative warming or routine thermal care. Measurements and Main Results: VO 2 was measured by indirect calorimetry preoperatively (T 0), immediately postoperatively (T 1), and 60 to 90 minutes later (T 2). For all patients, VO 2 was 57 ± 45% (mean ± SD) greater at T 1 than at T 0 ( p < 0.05). After isoflurane-N 2O-opioid general anesthesia, VO 2 increased 15 ± 20% in normothermic patients (core temperature, 36.4 ± 0.2 °C) compared with 69 ± 52% in hypothermic patients (35.0 ± 0.5 °C). After combined epidural-general anesthesia, VO 2 increased 86 ± 39% on emergence in normothermic (36.4 ± 0.2 °C) and 58 ± 11% in hypothermic (35.1 ± 0.4 °C) patients. Conclusions: Total-body VO 2 was increased in the immediate postoperative period. After general anesthesia, the magnitude of the increase in VO 2 was significantly less in normothermic patients than in hypothermic patients. After combined epidural-general anesthesia, VO 2 was increased in normothermic and in hypothermic patients.

Preoperative Analgesia with Epidural Morphine

In a prospective double-blind study, we examined the effects of preoperative epidural morphine associated with general anesthesia (GA) on intra- and postoperative analgesic requirements over a 3-day postoperative period. Twenty patients scheduled for major intraabdominal surgery were randomly assigned to two groups: a control group (n = 10) and an epidural group (n = 10) which received an epidural injection of 5 mg of preservative-free morphine in 10 mL of 0.9% saline. Afterward, both groups received the same GA. Postoperative pain relief was achieved with intravenous (IV) boluses of morphine using a patient-controlled analgesia device. We found smaller opioid requirements in the epidural group than in the control group for intraoperative fentanyl (465 +/- 179 micrograms vs 983 +/- 682 micrograms), for postoperative morphine at 12 h (3.1 +/- 3 mg vs 21.4 +/- 13.8 mg) and 24 h (9.1 +/- 6.4 mg vs 20.6 +/- 9.8 mg), and for the cumulated needs over the 3-day postoperative period (37 +/- 24 mg vs 86 +/- 42 mg). The consumption of IV morphine by the control group decreased over time (P < 0.001, r = 0.44), whereas, in the epidural group, consumption remained constant and small during the 3 days. The maximum pain score was significantly lower in the epidural group than in the control group at 24 h (0.65 +/- 2.4 vs 3 +/- 2), at 36 h (0.3 +/- 0.6 vs 3 +/- 2.7), and at 60 h (0.1 +/- 0.3 vs 1.8 +/- 1.2) after surgery. These results suggest that a single epidural injection of 5 mg of morphine before major surgery produces intra- and postoperative pain relief for at least 3 days.

Myocardial ischemia after orthotopic liver transplantation

A hypercoagulable state exists after orthotopic liver transplantation. This hematologic abnormality may predispose patients to coronary thrombosis and unstable angina. The incidence of post-operative myocardial ischemia in such patients is unknown. Suitable electrocardiograms and clinical events of consecutive patients undergoing orthotopic liver transplantation (n = 45) and major intraabdominal surgery (n = 28) during a 3-month period at a major university teaching hospital and transplant center were examined retrospectively. Clinical myocardial ischemia or ischemic electrocardiographic changes, or both, occurred in 6 transplant patients compared with no patient in the nontransplant or comparison group. In 4 of the 6 patients with dramatic electrocardiographic changes and ischemic events, coronary arteriography failed to demonstrate significant obstructive disease. It is concluded that severe myocardial ischemia may occur in patients after orthotopic liver transplantation in the absence of significant coronary disease. A hypercoagulable state may predispose to coronary thrombosis in this setting, providing insight (and a future model for study) into the development of unstable angina.

Small bowel motility following major intra-abdominal surgery: The effects of opiates and rectal cisapride

Background/Aims: Human small bowel motility is altered after laparotomy. Opiate analgesia is a possible cause of these alterations, and cisapride is a potential therapy. Methods: Continuous proximal small bowel manometry was performed for up to 92 hours in 23 patients after major intra-abdominal surgery. They were treated with rectal cisapride (30 mg three times daily) or placebo until the clinical resolution of ileus. Small bowel manometry was performed for 30 hours in 5 volunteers receiving 1 mg/kg meperidine over 3 hours. Results: Phase III activity was present within 3 hours of the end of surgery in all patients. Initially, the migrating motor complex (MMC) period was markedly reduced (mean, 22 minutes) but gradually increased. Phase II activity was absent until a median of 40 hours had elapsed. Phase III contractile amplitude was markedly attenuated in the jejunum, in contrast to that in the duodenum, presumably as a result of dilatation and/or altered tone, increasing to normal by 72 hours. In the volunteer group, although the MMC period was reduced by meperidine, it remained significantly greater than that of the placebo patient group for approximately 48 hours and phase II was reduced but not eliminated. Cisapride induced some changes in motor activity but did not accelerate the recovery of normal motility. Clinical outcome, assessed by the return of bowel sounds and passage of flatus, was accelerated by cisapride, but the trend was not significant (P = 0.11). Conclusions: This is the first published study using prolonged manometry to show the gradual evolution of small bowel motor activity after major intra-abdominal surgery. The findings suggest that surgery decreases the MMC period to the equivalent of the absolute refractory period, thereby eliminating phase II, which returns as the MMC period lengthens. Cisapride, at the dosage given, confers only modest benefit.

Stress hormone responses to major intra-abdominal surgery during and immediately after sevoflurane-nitrous oxide anaesthesia in elderly patients

We studied the responses of plasma epinephrine, norepinephrine, adrenocorticotropic hormone (ACTH), cortisol, and antidiuretic hormone (ADH) during and immediately after sevoflurane-nitrous oxide anaesthesia supplemented with vecuronium in seven elderly patients (mean 76.6 +/- 1.7 SEM) who underwent major intra-abdominal surgery. The plasma concentrations of norepinephrine, ACTH, cortisol, and ADH increased in response to surgical procedures (P < 0.05). The plasma concentration of ADH increased to a peak concentration of 189.1 +/- 20.7 pg.ml-1 30 min after skin incision (P < 0.05). The plasma concentrations of epinephrine, norepinephrine, ACTH, and cortisol increased to peak concentrations of 408.6 +/- 135.5 pg.ml-1, 635.7 +/- 167.8 pg.ml-1, 222.6 +/- 48.0 pg.ml-1, and 113.6 +/- 67.5 micrograms.dl-1, respectively immediately after tracheal extubation (P < 0.05). We conclude that, in the elderly patients, the responses of stress hormones to major intra-abdominal surgery were preserved during sevoflurane-nitrous oxide anaesthesia sufficient to prevent increases in arterial pressure and heart rate. The strongest responses of epinephrine, norepinephrine, ACTH, and cortisol were elicited immediately after tracheal extubation.

Spinal anesthesia for cesarean delivery with meperidine as the sole agent

Meperidine, a phenylpiperidine opioid analgesic, has been noted to have local anesthetic properties when injected intrathecally. The majority of reports using meperidine as the sole agent for spinal anesthesia have included only patients undergoing lower extremity, perineal or urologic procedures.‘-4 The use of intrathecal meperidine to provide anesthesia for major intra-abdominal surgery, such as cesarean delivery, has been reported only in abstract form.’ Moreover, the degree of neonatal exposure to meperidine after maternal intrathecal injection is unknown. We describe here our experience with a patient in whom extenuating medical circumstances prompted the use of this unconventional anesthetic technique.

Is routine postoperative nasogastric decompression really necessary?

Controversy exists regarding the need for nasogastric tube decompression and the incidence of complications resulting from its use following major intra-abdominal surgery. To determine the value of such tubes, 100 patients were managed after surgery with a nasogastric tube in situ until the passage of flatus per rectum (Group I). In a second group of 100 patients, no nasogastric tube was placed after surgery unless vomiting, gross distention, or overt obstruction occurred (Group II). In Group I, the nasogastric tube remained in place an average of 6 days and five patients required replacement of the tube after its initial removal. In Group II, nasogastric intubation was required at some point after surgery in six patients. No aspiration pneumonia, nasal septum necrosis, anastomotic leak, or wound dehiscence was seen in either group. There were three wound infections in Group I and two in Group II. The most obvious difference was the increased comfort and mobility of the group of patients treated without routine nasogastric decompression (Group II). Routine use of the nasogastric tube adjunct to patient care following gastrointestinal tract surgery may be safely eliminated.

Crossover femorofemoropopliteal sequential bypass for combined ipsilateral iliac and femoropopliteal occlusive disease.

We evaluated the effectiveness of crossover femorofemoropopliteal sequential bypass in 13 patients with combined ipsilateral iliac and femoropopliteal disease. Of them, eight underwent bypass grafting for limb salvage, and five, for disabling claudication. Four of the patients with claudication had relief of symptoms and significant increases in treadmill walking time. The cumulative limb salvage rate in the patients operated on for limb salvage was 88%. At 42 months, the cumulative patency rate for the femorofemoral portion of the graft was 91%, and for the distal segment, 63%. Mean ankle-brachial indices increased from 0.37 +/- 0.12 preoperatively to 0.76 +/- 0.16 postoperatively in the recipient limb. Early experience suggests that crossover sequential femorofemoropopliteal bypass grafts are effective in achieving limb salvage and relief of claudication, especially in patients with relative contraindications to major intra-abdominal surgery.

Pharmacokinetics of pethidine during anaesthesia and patient-controlled analgesic therapy.

The pharmacokinetics of pethidine has been studied in 12 patients subjected to major intraabdominal surgery. Pethidine and norpethine were analyzed in plasma samples collected during anesthesia and during patient-controlled administration of small intravenous doses of pethidine in the early postoperative period. A second study on the pharmacokinetics of pethidine was performed on the 3-5th postoperative day. The plasma clearance of pethidine was significantly lower in the preoperative study (8.9 +/- 1.8 ml x kg x min-1) compared with the postoperative study (12.0 +/- 3.1 ml x kg x min-1). Volume of distribution (Vd) was not significantly influenced, being 4.25 +/- 1.72 l x kg-1 peroperatively and 3.14 +/- 0.84 l x kg-1 postoperatively. Elimination half-life decreased from 5.91 +/- 3.57 h peroperatively to 3.25 +/- 1.40 h postoperatively. The kinetics of pethidine in the postoperative study agreed with pethidine kinetics reported for healthy volunteers. The fraction of unbound pethidine decreased from 0.26 +/- 0.1 peroperatively to 0.18 +/- 0.1 postoperatively. Norpethidine, a metabolite of pethidine, has been claimed to be responsible for several side effects like respiratory depression and convulsions during pethidine therapy. No side effect attributable to norpethidine was observed in the self-administration period. Norpethidine plasma concentrations did not exceed 500 ng/ml. The altered pethidine pharmacokinetics during anesthesia and the ensuing postoperative hours and the interindividual differences of the disposition of the drug strongly suggest that pethidine should be given by individualized regimens in surgical patients.

Estimation of postoperative fluid requirements in infants and children.

A quadrant scheme is presented for estimating postoperative fluid volumes for replacement of internal fluid shifts (third space losses) in pediatric surgical patients undergoing major intraabdominal surgery. The benefits derived from using a prescribed postoperative fluid management program that includes this quadrant scheme are determined by analyzing a series of 50 consecutive patients managed by five senior general and thoracic surgical house officers. Although the program tended to overestimate the fluid needs of the patients relative to a predetermined optimal urine output level, all but two patients with septic complications were hemodynamically stable and none had complications due to the fluid administration program.

TOTAL SPINAL ANAESTHESIA

One hundred patients were given total spinal anaesthesia for major intra-abdominal surgery. Operating conditions were excellent, superior to that provided by relaxant general anaesthesia and free f...

Rate of water and sodium absorption from the jejunum after abdominal surgery in man

Five patients were given intrajejunal infusions at a 10 cc per minute pumping rate before and after major intra-abdominal surgery. Net water and sodium absorption fell from a preoperative value of 2.2 cc per minute to a postoperative value of 1.2 cc per minute in a 30 cm length of jejunum immediately distal to the infusion site in the proximal jejunum. However, net absorption was not abolished and the infusions were well tolerated except for mild cramps after sixty minutes in two patients, suggesting that jejunal motility during clinical postoperative ileus is sufficient to propel large amounts of unabsorbed fluid from the infusion site to more distal intestine to prevent local distention. Intrajejunal infusions at much lower rates (2 cc per minute) were well tolerated for thirty-six continuous hours in three postoperative patients, and maintained hydration without supplemental intravenous fluids.