Anesthetic management of a massively morbidly obese patient

BACKGROUND AND OBJECTIVES

A 408-kg patient presented for surgical resection of a lower extremity mass.

METHODS

A specially designed bed and well-planned transport were used to deliver the patient to the operating room suite. The anesthetic technique included a continuous subarachnoid catheter with tetracaine and epinephrine. Intraoperative monitoring consisted of electrocardiography, pulse oximetry, intraarterial blood pressure, and mental status examinations. Massive intraoperative hemorrhage was treated with rapid volume infusions and vasopressors.

RESULTS

Resection of a lower extremity mass was accomplished and the patient was eventually discharged from the hospital.

CONCLUSIONS

The case report emphasizes that prior planning of all aspects of patient care is important in massively morbidly obese patients and that regional anesthesia is a valuable option in these patients.

The job outlook in brief 1990-2005

Every 2 years, the Bureau of Labor Statistics publishes a summary of the expected change in employment for about 250 occupations. Here are the most recent projections, along with the available information on the expected competition for jobs.

Experimental short-bowel syndrome: effect of an elemental diet supplemented with short-chain triglycerides

To determine whether short-chain triglycerides (SCTs, 1:1 triacetin:tributyrin, wt:wt) enhance intestinal adaptation in short-bowel syndrome (SBS), male Sprague-Dawley rats underwent 60% distal small-bowel resection with cecectomy and received either a chemically defined diet (CD) or a CD containing 40% of nonprotein energy as either medium-chain triglycerides (MCTs) or SCTs. After 12 d the SCT group had significantly increased jejunal mucosal weight compared with the MCT and CD groups and had significantly increased segment weight and mucosal protein compared with the CD group. In the colon the SCT group had significantly increased segment and mucosal weights and mucosal protein and DNA compared with both the MCT and CD groups. Body-weight change and measurements of serum ketones, albumin, glucose, and triglycerides revealed no significant differences among groups. SCTs improved jejunal and colonic adaptive growth and maintained comparable nutritional status in SBS when compared with CD alone or CD with MCTs.

Arthroscopy update #8. Auxiliary portal for assessing patellofemoral alignment

An auxiliary arthroscopic portal may be used to improve visualization and evaluation of the patellofemoral joint. A reusable transquadriceps tendon portal, which assesses patellar alignment within a 0 degree to 90 degrees range of motion, is described.

Stimulation of intestinal mucosal growth with intracolonic infusion of short-chain fatty acids

Dietary fiber, which stimulates intestinal mucosal growth, is fermented by anaerobic bacteria in the rat hindgut to the short-chain fatty acids (SCFA) acetate, propionate, and butyrate. Butyrate is the preferred oxidative fuel of the colonocyte in vitro, and the provision of preferred intestinal fuels has been shown to stimulate mucosal proliferation in vivo. This study determined whether chronic colonic infusion of butyrate or a combination of SCFA would stimulate intestinal mucosal growth in an animal deprived of its normal source of SCFA, fiber fermentation in the cecum. Adult male Sprague-Dawley rats were fed a fat- and fiber-free elemental liquid diet and underwent cecectomy, ileocolic anastomosis, and insertion of a proximal colonic infusion catheter. Rats were then assigned to receive either a continuous infusion of butyrate (20 mM, 40 mM, or 150 mM), SCFA (70 mM acetate + 35 mM propionate + 20 mM butyrate), or saline, or to receive no infusion. A seventh group underwent proximal colonic transection and reanastomosis. After 7 days, jejunal, ileal, and proximal colonic segments were analyzed for mucosal weight, protein, RNA, and DNA. In the colon, the 40-mM butyrate infusion resulted in significant elevations in all mucosal parameters relative to all three control groups, saline infusion, no infusion, and transection. Both the 20-mM butyrate and the SCFA groups showed increased colonic mucosal DNA compared to controls. In the jejunum and ileum, mucosal DNA content was significantly greater in the SCFA group than in the control groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Ultrasound surveillance of the cervix during pregnancy in diethylstilbestrol-exposed offspring

Twenty-three diethylstilbestrol (DES)-exposed patients were evaluated through 27 pregnancies to determine their eligibility for admission to a prospective protocol that combined serial ultrasound surveillance of the lower uterine segment-cervical complex with periodic pelvic examinations to diagnose cervical incompetency. Of these, 21 pregnant women, including seven vaginectomy patients, were matched to 84 low-risk controls to determine the following: 1) the effect of DES exposure on reproductive performance, 2) the efficacy of ultrasound selection of cerclage candidates, and 3) the influence of previous partial vaginectomy on reproductive outcome. Five DES-exposed patients were diagnosed as having cervical incompetency and had cerclages placed. There were no missed diagnoses of cervical incompetency. The DES-exposed patients delivered statistically earlier in gestation than did controls (268 +/- 13 versus 276 +/- 10 days). It was not evident that this difference was important clinically, as there were no neonatal deaths, very low birth weight infants, second-trimester losses, or deliveries before 252 days (36 weeks) among the study patients. Previous vaginectomy did not affect the frequency of the diagnosis of cervical failure or the neonatal outcome. After ultrasound surveillance and treatment for incompetent cervix, a majority of our patients delivered at term without cerclage placement. Therefore, routine cerclage placement is not recommended. Knowledge of the ultrasound criteria for diagnosing cervical incompetency is required.

Receptor binding affinity and thermolysin degradation of truncated and retro-inverso-isomeric ANF analogs

The peptides H-Phe-Gly-Gly-Arg-Ile-Asp-Arg-Ile-NH2 (rANF8-15-NH2), Ac-Phe-Gly-Gly-Arg-Ile-Asp-Arg-Ile-NH2 (Ac-rANF8-15-NH2), and their corresponding retro-inverso-isomeric peptides H-D-Ile-D-Arg-D-Asp-D-Ile-D-Arg-Gly-Gly-D-Phe-NH2 (D-rANF15-8-NH2), Ac-D-Ile-D-Arg-D-Asp-D-Ile-D-Arg-Gly-Gly-D-Phe-NH2 (Ac-D-rANF15-8-NH2), were evaluated for their ability to compete for the binding of 125I-rANF5-28 to cultured spontaneously hypertensive rat (SHR) aortic smooth muscle cell membranes. Their stability toward hydrolysis by the neutral endopeptidase thermolysin was also studied. The octapeptides rANF8-15-NH2 and Ac-rANF8-15-NH2 bound with IC50's of 367 pM and 1900 pM, respectively, but were rapidly hydrolyzed by thermolysin. Retro-inverso-isomers were prepared to provide molecules with an improved enzymatic stability. The retro-inverso-isomers were completely stable to thermolysin but were virtually inactive in the binding assay (IC50 greater than 1 microM).

Design and synthesis of metabolically stable atrial natriuretic factor analogs. Amino- and carboxy-terminal stabilization

Two analogs of rat atrial natriuretic factor, rANF7-28-NH2 and [Mpr7,Ala20,D-Arg27]rANF7-27-NH2, were prepared by the solid-phase method. These peptides had 2-fold and 7-fold less affinity, respectively, than rANF1-28 in binding to membranes prepared from cultured aortic smooth muscle cells, and both peptides were 5-fold less potent than rANF1-28 in relaxing serotonin-contracted rabbit aortic rings. rANF7-28-NH2 was rapidly degraded by rat kidney homogenates but [Mpr7,Ala20,D-Arg27]rANF7-27-NH2 had enhanced stability against rat kidney homogenate degradation. However, this in vitro stability did not translate into an extended duration of action in vivo.

Synthesis and activity of partial retro-inverso modified atrial natriuretic factor analogs

The synthesis and pharmacological activity of partial retro-inverso modified rat atrial natriuretic factor (rANF) analogs is described. The route to these compounds utilized a combination of solution and solid-phase methods. The analogs prepared all contain a reversed amide bond (psi[NHCO]) at the Ser 25 to Phe26 linkage. This bond has been suggested to play a key role in the metabolic inactivation of ANF. The analogs are of comparable potency to the endogenous peptide rANF1-28 in binding to cultured rat vascular smooth muscle cells, in relaxing serotonin contracted rabbit aortic rings, and as natriuretic/diuretic agents in anesthetized rats. None of the peptides has an extended duration of action in vivo.

Effect of a glutamine-supplemented enteral diet on methotrexate-induced enterocolitis

Administration of an elemental diet to rats given methotrexate (MTX), 20 mg/kg intraperitoneally (ip), results in 100% mortality from severe enterocolitis. Previous studies indicate that glutamine (GLN), which is not present in elemental diets, is the preferred oxidative substrate for the gut and may facilitate intestinal recovery after injury. This study investigated the effects of a glutamine-supplemented elemental diet (GLN-ED) on nutritional status, intestinal morphometry, bacterial translocation and survival in this lethal model of intestinal injury. Three experiments were performed. In the first experiment, rats received an intragastric elemental diet supplemented with either 2% GLN or an equivalent amount of glycine (Control). After 4 days animals received either MTX, 20 mg/kg ip, or saline ip and were killed 3 days later. The GLN-ED resulted in significantly decreased weight loss, improved nitrogen retention, and increased mucosal weight, protein, and DNA content of the jejunum and colon. In the second experiment rats were assigned to diet as in the first experiment, but all animals received MTX. Control diet animals died within 120 hrs of MTX administration. The GLN-ED group had significantly longer survival time and decreased mortality. In the third experiment animals were assigned to diet and MTX as in the first experiment. Ninety-six hrs later aortic blood cultures revealed enteric bacteremia in animals administered MTX. GLN-ED resulted in a significant reduction in the incidence of bacteremia. These experiments showed that a GLN-ED significantly improved nutritional status, decreased intestinal injury, decreased bacterial translocation, and resulted in improved survival in a lethal model of enterocolitis.

Dexamethasone administration induces increased glutaminase specific activity in the jejunum and colon

Exogenous glucocorticoids markedly increase the in vivo uptake and utilization of glutamine by the intestine. Since glutamine is the major oxidative fuel for the small intestine, we investigated whether glucocorticoids induce changes in the specific activity of the enzymes that mediate glutamine degradation (glutaminase) and synthesis (glutamine synthetase). Male Sprague-Dawley rats received a 7-day elemental diet. On Day 5, animals were randomized to one of four groups and received either saline (Control) or one of three doses of dexamethasone im: 0.1 mg/kg (Lodex); 0.3 mg/kg (Middex); or 0.6 mg/kg (Hidex). Forty-eight hours later jejunal and colonic segments were assayed for protein, glutaminase, and glutamine synthetase activity. A stress dose of dexamethasone (Hidex) produced a significant increase in both jejunal and colonic glutaminase specific activity (P less than 0.02 vs Control and P less than 0.05 vs Control, respectively). These data suggest a mechanism whereby glucocorticoids increase the intestinal utilization of glutamine by increasing the specific activity of intestinal glutaminase.

Inhibition of TPN-associated intestinal mucosal atrophy with monoacetoacetin

Total parenteral nutrition (TPN) is associated with intestinal mucosal atrophy. Acetoacetate is oxidized in preference to glucose by both enterocytes and colonocytes and is not present in TPN. The purpose of this study was to determine whether replacement of a portion of glucose calories with monoacetoacetin, the glycerol ester of acetoacetate, could inhibit TPN-associated intestinal atrophy. Male Sprague-Dawley rats (200-250 g) underwent superior vena caval cannulation and were assigned to receive chow ad libitium (CHOW), TPN with 0.86 M monoacetoacetin (ACAC), or TPN with 0.86 M glycerol to control for the glycerol component of monoacetoacetin (GLYC). Nitrogen balance was measured over 7 days after which time the animals were weighed and sacrificed. Jejunal and colonic segments were harvested and the mucosal weight, protein, RNA, and DNA contents measured. All groups showed comparable weight gain. Cumulative nitrogen balance was positive for both TPN groups. Significant decreases in mucosal parameters occurred in both TPN groups compared to the CHOW group, but atrophy was significantly inhibited in both jejunum and colon of the ACAC group compared to the GLYC group. Thus, the substitution of monoacetoacetin for glucose calories in parenteral nutrition solutions inhibited TPN-related atrophy of intestinal mucosa while maintaining normal growth.

In vitro processing of rANF7-28-NH2 by rat kidney homogenates

The major rat kidney in vitro degradation products of the rat atrial natriuretic factor analog, H-Cys7-Phe-Gly-Gly-Arg-Ile-Asp-Arg-Ile-Gly-Ala-Gln-Ser-Gly-Leu-Gly -Cys-Asn-Ser-Phe-Arg-Tyr28-NH2 (with a Cys27-Cys23 disulfide bridge), have been identified. The degradation products are the C-terminal modified compounds rANF7-27, rANF7-26, and rANF7-25.

Synthesis of cyclic and acyclic partial retro-inverso modified enkephalins

The cyclic partial retro-inverso modified enkephalins, H-Tyr-cyclo[-D-Glu-Gly-gPhe-D-Leu-] (I), H-Tyr-cyclo[-D-A2bu-Gly-gPhe-R&S-mLeu-] (IIf, IIs), and H-Tyr-cyclo[-D-Glu-Gly-Phe-gLeu-] (III), have been synthesized by solution methodology. In a like manner, their corresponding acyclic analogs Ia-IIIa containing D-Ala2 have also been prepared. Gem-diaminoalkyl residues were generated by conversion of Boc-dipeptide carboxamide to the corresponding gem-diaminoalkyl "dipeptide" salt using [bis(trifluoroacetoxy)iodo] benzene. Cyclizations were achieved at high dilution utilizing diphenylphosphoryl azide as the coupling reagent.

Treatment of theophylline toxicity with oral activated charcoal

Oral activated charcoal was administered to 4 patients with theophylline toxicity, who had gastrointestinal and neurologic symptoms as well as cardiac arrhythmias. Administration of oral charcoal significantly reduced the theophylline half-life in the serum of each patient. The charcoal was well tolerated and symptoms of toxicity rapidly resolved. We conclude that administration of oral charcoal rapidly reduces the serum theophylline concentration and should be used as the initial treatment in patients with theophylline toxicity.

Increased serum theophylline clearance with orally administered activated charcoal

The purpose of this study was to determine whether the oral administration of activated charcoal would increase the clearance of theophylline. Seven normal subjects received aminophylline intravenously (8 mg/kg) on 2 separate days. On Day 1 at 2-h intervals starting immediately after the completion of the aminophylline infusion, subjects ingested 4 doses of a slurry of activated charcoal (30 g each). On Day 2 they received no charcoal. The order of the days the subjects received charcoal or no charcoal was randomized. Plasma theophylline levels were determined by an enzyme immunoassay (Syva) every 2 h after the completion of the intravenous infusion. The theophylline half-life was reduced with charcoal from 10.2 to 4.6 h (p less than 0.001), and clearance increased from 35.6 to 72.6 ml/kg/h (p less than 0.001). In a patient with an initial serum theophylline concentration of 31.0 micrograms/ml and signs of toxicity (arrhythmias and seizures), the administration of charcoal (4 doses of 30 g every 2 h) reduced the half-life from 34.4 to 5.7 h concomitant with rapid resolution of signs of toxicity. We conclude that orally administered activated charcoal significantly enhances the clearance of theophylline and offers a new therapeutic modality in the treatment of theophylline toxicity.

Cyclic and acyclic partial retro-inverso enkephalinamides: Mu receptor selective enzyme resistant analogs

The cyclic partial retro-inverso modified enkephalins, H-Tyr-cyclo[-D-Glu-Gly-gPhe-D-Leu-] (I), H-Tyr-cyclo[-D-A2bu-Gly-gPhe-R&S-mLeu-] (IIf, IIs), H-Tyr-cyclo[-D-Glu-Gly-Phe-gLeu-] (III), and their corresponding acyclic analogs, H-Tyr-D-Ala-Gly-gPhe-D-Leu-For (Ia), H-Tyr-D-Ala-Gly-gPhe-R,S-mLeu-NH2 (IIa), H-Tyr-D-Ala-Gly-Phe-gLeu-For (IIIa) have been evaluated in in vitro bioassays. Relative to Leu-enkephalin, the modified compounds are more potent in the guinea pig ileum assay and more effectively displace [3H]naloxone from rat brain receptors, while they are generally less potent in the mouse vas deferens assay and only weakly able to displace [3H] (D-Ala2, D-Leu5)enkephalin. The analogs are highly resistant to proteolytic degradation by rat brain membrane preparations that readily hydrolyze Leu-enkephalin.

Peptide sweeteners. 5. Side-chain homologues relating zwitterionic and trifluoroacetylated amino acid anilide and dipeptide sweeteners

Side-chain homologues of sweet trifluoroacetyl-alpha-L-aspartyl-p-cyanoanilide have been synthesized and tasted. Removal of the trifluoroacetyl group only changes the potency of sweet taste, not the taste property. These results have been compared with the structure-taste relationships of dipeptide sweeteners. An informative discontinuity of taste effects was found to exist with novel aminomalonyl dipeptide derivatives. The results are explained on topochemical grounds.

Ampicillin-resistant H influenzae cellulitis and shock in an adult

Over a three-day period, pharyngitis, neck swelling, deep voice, dysphagia, fever, and cellulitis of the anterior neck and upper chest developed in a 63-year-old woman. Sixteen hours following the institution of intravenous ampicillin, septic shock developed and the patient became comatose. Ampicillin-resistant Hemophilus influenzae type B was found in a culture taken from her blood and pharynx. In patients who have an upper respiratory tract infection and severe cellulitis of the neck, initial therapy should include chloramphenicol because of the possibility of ampicillin-resistant Hemophilus influenzae infection.