Comparison of the Baska(®) mask with the single-use laryngeal mask airway in low-risk female patients undergoing ambulatory surgery

We compared the Baska(®) mask with the single-use classic laryngeal mask airway (cLMA) in 150 females at low risk for difficult tracheal intubation in a randomised, controlled clinical trial. We found that median (IQR [range]) seal pressure was significantly higher with the Baska mask compared with the cLMA (40 (34-40 [16-40]) vs 22 (18-25 [14-40]) cmH2O, respectively, p < 0.001), indicating a better seal. In contrast, the first time success rate for insertion of the Baska mask was lower than that seen with the cLMA (52/71 (73%) vs 77/99 (98%), respectively, p < 0.001). There were no differences in overall device insertion success rates (78/79 (99%) vs 68/71 (96%), respectively, p = 0.54). The Baska mask proved more difficult to insert, requiring more insertion attempts, taking longer to insert and had higher median (IQR [range]) insertion difficulty scores (1.6 (0.8-2.2 [0.1-5.6]) vs 0.5 (0.3-1.4 [0.1-4.0]), respectively, p < 0.001). There was also an increased rate of minor blood staining of the Baska mask after removal, but there were no differences in other complication rates, such as laryngospasm, or in the severity of throat discomfort. In conclusion, in clinical situations where the seal with the glottic aperture takes priority over ease of insertion, the Baska mask may provide a useful alternative to the cLMA.

Collaboration between an internal medicine residency program and a federally qualified health center: Norwalk Hospital and the Norwalk Community Health Center

In 1999, Norwalk Hospital and an independent, community-based board collaboratively developed the Norwalk Community Health Center (the NCHC). The objectives of the affiliation were to (1) create a new, free-standing, high-quality community health center, (2) optimize grant and clinical revenue, (3) create an ideal venue for ambulatory care training for residents, and (4) replace the traditional and increasingly inefficient hospital-based primary care clinics. The hospital transferred all of its primary care clinical activity to the new community health center and provides an ongoing financial subsidy of the NCHC operations via a forgivable loan. In exchange, the NCHC granted Norwalk Hospital 24% of the seats on its board of directors and purchases all primary care provider services from the hospital. For adult medicine, the contract providers are exclusively Norwalk Hospital internal medicine residents and faculty. Contract charges are based not upon actual staffing but upon a standard formula relating full-time-equivalent providers to patient visits. The new 10,000 square-foot NCHC contains 2,500 square feet of additional integrated space, rented from the NCHC by Norwalk Hospital, which supports the residency education program. The NCHC opened in April 1999 and received FQHC status in November 1999. Adult medicine volume increased 30%, from 36.8 daily visits in the old hospital-based clinics to 48.0 at the NCHC. Resident and patient satisfaction are high. The NCHC now receives cost-based visit reimbursement from Medicaid and has received $1.8 million in state, federal, and local grants.

Role and mechanism of PKC in ischemic preconditioning of pig skeletal muscle against infarction

Protein kinase C (PKC) inhibitors, chelerythrine (Chel, 0.6 mg) and polymyxin B (Poly B, 1.0 mg), and PKC activators, phorbol 12-myristate 13-acetate (PMA, 0.05 mg) and 1-oleoyl-2-acetyl glycerol (OAG, 0.1 mg), were used as probes to investigate the role of PKC in mediation of ischemic preconditioning (IPC) of noncontracting pig latissimus dorsi (LD) muscles against infarction in vivo. These drugs were delivered to each LD muscle flap (8 x 12 cm) by 10 min of local intra-arterial infusion. It was observed that LD muscle flaps sustained 43 +/- 5% infarction when subjected to 4 h of global ischemia and 24 h of reperfusion. IPC with three cycles of 10 min ischemia-reperfusion reduced muscle infarction to 25 +/- 3% (P < 0.05). This anti-infarction effect of IPC was blocked by Chel (42 +/- 7%) and Poly B (37 +/- 2%) and mimicked by PMA (19 +/- 10%) and OAG (14 +/- 5%) treatments (P < 0.05), given 10 min before 4 h of ischemia. In addition, the ATP-sensitive K(+) (K(ATP)) channel antagonist sodium 5-hydroxydecanoate attenuated (P < 0.05) the anti-infarction effect of IPC (37 +/- 2%), PMA (44 +/- 17%), and OAG (46 +/- 9%). IPC, OAG, and Chel treatment alone did not affect mean arterial blood pressure or muscle blood flow assessed by 15-microm radioactive microspheres. Western blot analysis of muscle biopsies obtained before (baseline) and after IPC demonstrated seven cytosol-associated isoforms, with nPKCepsilon alone demonstrating progressive cytosol-to-membrane translocation within 10 min after the final ischemia period of IPC. Using differential fractionation, it was observed that nPKCepsilon translocated to a membrane compartment other than the sarcolemma and/or sarcoplasmic reticulum. Furthermore, IPC and preischemic OAG but not postischemic OAG treatment reduced (P < 0.05) muscle myeloperoxidase activity compared with time-matched ischemic controls during 16 h of reperfusion after 4 h of ischemia. Taken together, these observations indicate that PKC plays a central role in the anti-infarction effect of IPC in pig LD muscles, most likely through a PKC-K(ATP) channel-linked signal-transduction pathway.

The local management of soft tissue sarcoma

Soft tissue sarcomas (STS) are rare tumors arising from the connective tissues. STS can arise at any anatomic site, can demonstrate varied behavior and prognosis, and therefore present a formidable challenge in management. The local treatment of STS demands technical complexity in the application of diagnostic tools, including pathology and imaging, as well as treatment approaches, including surgical ablation and reconstruction, radiotherapy, and, in defined cases, chemotherapy. The understanding of the management of these lesions is profoundly dependent on the multidisciplinary setting, where experience has been gained and skills are available to increase the likelihood of a successful result. Several proven options are available for optimal local management, and the choice of approach depends on the prevailing practice and resource profile of the treating center. With modern approaches, the local control rate can be expected to be at least 90% for extremity lesions, which constitute the most common STS. The experience in other anatomic sites is less favorable as a result of a combination of late diagnosis, technically difficult access sites, and possibly less familiarity with these less common presentations. The disappointing results make it all the more important for patients to be referred to a multidisciplinary setting with experience in sarcoma management to maximize the chance of successful local outcome.

Prolonged perioperative myocardial ischemia in a young male: due to topical intranasal cocaine?

We present a case of prolonged myocardial ischemia in a young healthy male presenting for nasal polypectomy and tonsillectomy. Induction of anesthesia proceeded uneventfully. Immediately after surgical incision, the patient developed a sinus tachycardia with ST-segment depression in leads II and III, and ST elevation in leads aVR, aVL, aVF, and V. Depth of anesthesia was increased, esmolol was administered, which slowed the heart rate, and the procedure was terminated. However, myocardial ischemia only gradually resolved, leaving residual T-wave flattening in lead III by day 3 postoperatively. After extensive investigation to rule out other causes of ischemia, we considered cardiotoxicity due to intranasally administered cocaine with epinephrine to be the most likely precipitant. Nasal packing with gauze soaked in a solution containing cocaine 3 mg/kg and epinephrine 1 mg occurred just 40 minutes prior to induction of anesthesia. Topical intranasal cocaine is rapidly and reliably absorbed systemically, with peak plasma concentrations occurring within 30 to 60 minutes, corresponding to the time course of cocaine administration and surgical stimulation in this patient. Systemic absorption of topical intranasal cocaine has previously been reported to cause adverse cardiac sequelae, including myocardial infarction. This report reinforces the need for caution regarding the use of topical intranasal cocaine, particularly if used in combination with epinephrine.

A retrospective comparison of the morbidity and cost of different reconstructive strategies in oral and oropharyngeal carcinoma

PURPOSE

Evaluate and compare the morbidity and costs of different reconstructive strategies in oral and oropharyngeal carcinoma.

STUDY DESIGN

Retrospective cross-sectional.

PATIENTS AND METHODS

One hundred twenty-seven consecutive patients treated surgically for oral and oropharyngeal carcinoma between 1990 and 1996 were evaluated. Sixty-three patients had segmental mandibulectomies with 30 plate-soft tissue reconstructions and 33 bone-soft tissue flaps. Sixty-four patients had soft-tissue-only reconstructions. The following outcome parameters were analyzed: operative time, intraoperative blood loss, postoperative admission length, ICU and coronary care unit admission length, surgical interventions for complications, re-admissions, and prolonged (>6 mo) gastrostomy tube feeding, and all costs within the disease-free interval. Means and standard deviations were calculated for continuous parameters. Differences among the three groups were analyzed using one-way analysis of variance. For discontinuous parameters, the chi-square test was applied.

RESULTS

Longer operative time (1.8 h) and more blood loss (150 mL) for bone-soft tissue flaps were the only statistically significant findings (P<.05) between the three groups.

CONCLUSION

There is no rationale for allowing presumed factors of morbidity or cost select for type of reconstruction in patients with oral and oropharyngeal carcinoma.

Internal jugular vein thrombosis following modified neck dissection: implications for head and neck flap reconstruction

BACKGROUND

The incidence of internal jugular vein thrombosis (IJVT) following a modified neck dissection remains uncertain. The effect of, or consequences following, IJVT upon pedicled and free flap head and neck reconstructions remains unexplored.

METHODS

Twenty-nine preserved internal jugular veins in 24 patients undergoing modified neck dissection were available for prospective study. All patients required a pedicled or free flap reconstruction and received a modified, unilateral or bilateral cervical lymphadenectomy. The patency of all jugular veins was determined preoperatively and postoperatively using a combination of computed tomography (CT) scanning, high-resolution ultrasound, and color-flow Doppler (CFD).

RESULTS

The IJVT rate was 14%. The presence of a pedicled myocutaneous flap and left-sided jugular dissections may represent risks to the postoperative patency of the internal jugular vein. Preoperative radiotherapy did not appear to impact negatively upon the thrombosis rate.

CONCLUSIONS

Thrombosis of the internal jugular vein may result in significant morbidity for the postoperative oncologic patient. An internal jugular-dependent-free-tissue transfer may risk venous compromise of the flap, whereas the use of a pedicled flap may place the jugular at increased risk for thrombosis. Strategies for deep venous system microvascular recipient recruitment in the head and neck are discussed. Wherever possible, we employ two deep venous systems, the internal jugular, and subclavian (via the external jugular) for flap drainage.

Effector mechanism of adenosine in acute ischemic preconditioning of skeletal muscle against infarction

We used adenosine A1 receptor agonist N6-1(phenyl-2R-isopropyl)-adenosine (PIA), A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), and ATP-sensitive K+ (KATP) channel blockers sodium 5-hydroxydecanoate (5-HD) and glibenclamide (Glib), as probes to investigate the role and mechanism of adenosine in ischemic preconditioning (IPC) of noncontractile skeletal muscle against infarction, using the pig latissimus dorsi muscle flap model. Except for Glib, all drugs were delivered to each muscle flap by 10-min local intra-arterial infusion to avoid systemic effects. Muscle flaps that were subjected to 4 h of global ischemia and 48 h of reperfusion sustained 40 +/- 2% infarction. IPC with three cycles of 10 min ischemia and reperfusion, preischemic adenosine, or PIA treatment reduced (P < 0.05) muscle infarction to 24 +/- 2, 18 +/- 2, and 24 +/- 2%, respectively. The anti-infarction effect of IPC and adenosine was blocked by DPCPX, 5-HD, and Glib (P < 0.05). Preischemic adenosine treatment also maintained higher muscle contents of phosphocreatine, ATP, and energy charge potential and lower muscle contents of dephosphorylated metabolites and lactate during ischemia and a lower muscle myeloperoxidase (MPO) activity during reperfusion compared with the control (P < 0.05). Preischemic adenosine treatment did not increase muscle content of adenosine during ischemia or reperfusion. Furthermore, adenosine given at the onset of reperfusion was not effective in attenuating muscle MPO activity or infarction. Taken together, these observations indicate that adenosine, through A1 receptors, initiates the mechanism of IPC with postreceptor involvement of KATP channels in skeletal muscle. However, adenosine is unlikely to play a key role in the effector mechanism. Presently, the cause and role of energy sparing and neutrophil inhibitory effects associated with the anti-infarction effect of preischemic adenosine treatment are unknown.

Comparison of secondary ischemic tolerance between pedicled and free island buttock skin flaps in the pig

We compared the secondary ischemic tolerance of 8 x 12 cm surgically denervated pedicled island skin flaps and skin free flaps raised contralaterally on the buttocks of 50 pigs. The pedicled flaps and free flaps were subjected to 2 hours of primary warm global ischemia followed by 12 hours of reperfusion and 0, 2, 4, 6, or 10 hours of secondary warm global ischemia (n = 10 flaps). Skin necrosis was assessed 7 days after secondary ischemia. Pedicled skin flaps tolerated up to 10 hours of secondary ischemia without skin necrosis. However, incidences of skin necrosis (partial and total) in free flaps subjected to 0, 2, 4, 6, or 10 hours of secondary ischemia were 0, 10, 50, 80, and 100 percent, respectively. In a separate experiment, skin blood flow and hematology were studied in contralateral pedicled flaps and free flaps (n = 20) subjected to 4 hours of secondary ischemia. The skin blood flow measured by 15-micron microspheres at 1.5 hours of reperfusion was significantly higher (p < 0.01, n = 20) in pedicled skin flaps than in skin free flaps (1.91 +/- 0.35 versus 0.67 +/- 0.53 ml/min/100 gm). Under an operating microscope, microthrombi were observed near the arterial and/or venous anastomoses in 8 of 20 skin free flaps but none in the pedicled skin flaps. We obtained venous blood samples by cannulation of the major venae comitantes in 12 of the 20 skin free flaps in which there was no thrombosis in the vascular pedicle for hematologic studies. The venous plasma level of thromboxane B2 was significantly higher (p < 0.05) in the skin free flaps than in their contralateral pedicled skin flaps (195 +/- 49 versus 124 +/- 30 pg/ml). In addition, venous hematocrit, hemoglobin concentration, and white blood cell count also were significantly (p < 0.05) higher in skin free flaps compared with their contralateral pedicled skin flaps. Taken together, these observations were interpreted to indicate that buttock skin free flaps in the pig were less tolerant of secondary ischemia compared with their contralateral pedicled skin flaps subjected to the same ischemic protocol, and this reduced ischemic tolerance in skin free flaps was associated with compromised skin blood flow, hemoconcentration, and thrombosis in the vascular pedicle.

Role of ATP-sensitive K+ channels in ischemic preconditioning of skeletal muscle against infarction

We studied the role and mechanism of ATP-sensitive K+ (KATP) channels in ischemic preconditioning (IPC) of skeletal muscle against infarction in vivo. Surgically denervated, noncontractile latissimus dorsi muscle flaps in pentobarbitone-anesthetized pigs were assigned to nine groups: control; IPC (3 cycles of 10-min ischemia/reperfusion); preischemic lemakalim (LMK, 0.18 mg/muscle); postischemic LMK; sodium 5-hydroxydecanoate (5-HD, 27 mg/muscle) before IPC; glibenclamide (Glib 0.3 mg/kg iv) before IPC; 5-HD before preischemic LMK; 5-HD before ischemia; and Glib before ischemia. Except for Glib, all drugs were delivered to each muscle by 10-min local intraarterial infusion to avoid systemic effects. All muscle flaps underwent 4 h of global ischemia. Infarction was assessed at 48 h of reperfusion. In a separate study, muscle biopsies were taken before, during, and after ischemia for assay of high-energy phosphate and lactate contents and myeloperoxidase (MPO) activity. It was observed that muscle infarction in the IPC (24 +/- 2%) and preischemic LMK (21 +/- 2%) groups were smaller (P < 0.05) than that in the control (42 +/- 2%). The anti-infarction effect of IPC and LMK was blocked by 5-HD or Glib. IPC and preischemic LMK caused a higher (P < 0.05) muscle content of ATP and energy charge potential, a lower (P < 0.05) muscle content of lactate during ischemia, and a lower (P < 0.05) muscle MPO activity throughout 16 h of reperfusion compared with the control. These observations indicated for the first time that KATP channels are also involved in the anti-infarction effect of IPC in noncontractile skeletal muscle in vivo. Presently, the cause and importance of energy-sparing and neutrophil-inhibitory effects of IPC and LMK are not known.

Leg morbidity and function following fibular free flap harvest

Over a period of 3 years, 50 consecutive free fibular flaps for mandibular reconstruction were performed on 47 patients. In 38 patients (81%) a skin paddle was included with the flap to provide either mucosal lining or skin cover; in 9 patients (19%) bone alone was used. Thirty-one patients (66%) required a skin graft to close the donor defect in the leg. Donor leg morbidity and function were determined by patient questionnaire and by physical examination. Forty-one donor sites in 40 patients were available for long-term follow-up. The follow-up ranged from 4 to 39 months with an average of 17 months. Immediate postoperative infection occurred in the donor site of 1 patient (2%) and required additional surgery. There was no other immediate donor site complications when closure required skin grafting. Eleven patients (27%) had late donor site morbidity, consisting of motor weakness of the great toe in 5 patients, ankle instability and/or stiffness in 3 patients, donor site pain in 1 patient, and edema in 2 patients. All complications were graded as mild in severity by the patient and by the examiner. In this series, although most donor site defects required skin grafting, short- and long-term morbidity was minimal. After a short rehabilitation period, all patients were fully able to engage in all daily and recreational activities.

Outcome and analysis of the surgical management of esthesioneuroblastoma

OBJECTIVE

The aim of this study was to evaluate the effectiveness of combined radical surgical resection and radiotherapy for the treatment of esthesioneuroblastoma, a rare malignant neoplasm accounting for 1 to 5% of malignant neoplasms of the nasal cavity.

METHOD

A 10-year review of 12 patients treated at our institution suggests that primary treatment consisting of a combined otolaryngologic/neurosurgical craniofacial approach results in good local control with relatively low morbidity and complication. Patients tend to present with advanced stage disease because of the nonspecific presenting signs and symptoms. Eighty-three percent of the patients were treated with combined surgery and radiation.

RESULTS

Seventy-five percent of the patients are free of disease with an average follow-up time of 54 months. Based on our experience in anterior skull base surgery (zone I), we strongly advocate the pericranial flap for dural reconstruction. Postoperative complications occurred in 25% of the cases with no postoperative deaths.

CONCLUSION

Failure analysis suggests that radical surgical resection combined with radiotherapy provides the best chance of disease control.

Acute adenosine treatment is effective in augmentation of ischemic tolerance in muscle flaps in the pig

The objective of the present project was to investigate the efficacy and mechanism of acute (10-minute) adenosine treatment for augmentation of ischemic tolerance in muscle flaps in pigs. Varying doses of adenosine were infused into 28 latissimus dorsi muscle flaps through the axillary artery (0, 0.5, or 2.0 mg per flap) and 22 gracilis muscle flaps through the medial circumflex femoral artery (0, 10, or 20 mg per flap) over 10 minutes. Ten minutes after adenosine infusion, these muscle flaps were subjected to 4 hours of sustained warm global ischemia. In addition, one group of latissimus dorsi muscle flaps (n = 6) received a 10-minute intraarterial adenosine infusion (0.5 mg) at the beginning of reperfusion. Muscle biopsies (n = 4 or 5) for adenosine triphosphate (ATP) analysis were obtained before and after adenosine infusion and at the end of 4 hours of ischemia. The extent of muscle infarction was assessed at 48 hours of reperfusion by the tetrazolium dye staining technique. Muscle blood flow in latissimus dorsi muscle flaps was measured at the end of adenosine infusion (0 or 0.5 mg per flap, n = 8) by the radioactive microsphere (15-microns) technique. It was observed that adenosine, at all doses tested, significantly (p < 0.05) reduced the extent of muscle infarction in latissimus dorsi muscle flaps (control, 40.3 +/- 2.2 percent; 0.5 mg, 20.6 +/- 1.6 percent; 2.0 mg, 18.2 +/- 1 percent) and gracilis muscle flaps (control, 31.0 +/- 1.5 percent; 10 mg, 14.3 +/- 3 percent; 20 mg, 11.6 +/- 1.2 percent). Preischemic adenosine treatment (0.5 mg per flap) was associated with maintenance of a significantly (p < 0.05) higher muscle content of ATP in latissimus dorsi muscle flaps at the end of 4 hours of ischemia compared with saline-treated ischemic controls. Postischemic adenosine treatment did not protect latissimus dorsi muscle flaps against infarction. Furthermore, adenosine treatment did not have any significant effect on mean systemic arterial blood pressure or muscle blood flow in latissimus dorsi muscle flaps. It is concluded that acute (10-minute) preischemic adenosine treatment is effective in augmentation of ischemic tolerance in muscle flaps and that this protective effect of adenosine may be, at least in part, the result of slowing muscle ATP depletion during sustained ischemia. The possible mechanisms of this adenosine-induced energysparing effect are discussed.

Vascular effects and mechanism of action of endothelin-1 in isolated perfused pig skin

We investigated the vascular effects and mechanism of action of endothelin-1 (ET-1) in the skin by intra-arterial infusion of ET-1 and its precursor Big ET-1 via a direct cutaneous artery in isolated perfused pig skin flaps (6 x 16 cm). The vascular contractivity was studied by monitoring the perfusion pressure in the skin flap. There was evidence to indicate local conversion of Big ET-1 to ET-1 in the pig skin. It was also observed that ET-1 was a potent long-lasting vasoconstrictor with a potency of approximately 10- and 300-fold higher than those of Big ET-1 and norepinephrine, respectively. The vasoconstrictor action of ET-1 was blocked (P < 0.01) by a selective ETA-receptor antagonist (BQ-123 or BQ-610; 10(-7) M) and enhanced (P < 0.05) by a nitric oxide synthase inhibitor (NG-monomethyl-L-arginine or N omega-nitro-L-arginine methyl ester; 10(-5) M). ET-1-induced increase in perfusion pressure was attenuated (P < 0.05) by an L-type Ca(2+)-channel antagonist (nitrendipine, verapamil, or nifedipine; 10(-5) M) and by removal of Ca2+ from the perfusate. ET-1-induced increase in perfusion pressure was also attenuated (P < 0.05) by a phospholipase C inhibitor (neomycin; 10(-2) M), a protein kinase C (PKC) inhibitor (chelerythrine or H-7; 10(-5) M), and an intracellular Ca2+ chelator [1,2-bis(2-aminophenoxy)]ethane-N,N,N',N'-tetraacetic acid (BAPTA); 10(-5) M]. Furthermore, it was observed that the concentration-dependent (5 x 10(-8) to 10(-5) M) increase in perfusion pressure induced by phorbol 12,13-dibutyrate, a PKC activator, was not affected by verapamil (10(-5) M) or removal of Ca2+ from the perfusate. Taken together, these observations suggest that the vasoconstrictor mechanism of ET-1 in the pig skin involved activation of ETA receptors, L-type Ca2+ channels, phospholipase C, and PKC and that the vasoconstrictor effect caused by activation of PKC was independent of L-type Ca2+ channels.

Patient-controlled analgesia in burn patients: a critical review of the literature and case report

Although patient-controlled analgesia has been well documented as effective in various types of patients, it has not been adequately studied in burn patients. In this paper, the authors review the literature on PCA in burn patients and present two cases. Flaws in most published studies make it difficult to determine the efficacy of PCA in burn patients. Both the literature and experience indicate that many patients with acute burns are not suitable candidates for PCA. The cases illustrate the different methods patients may use to achieve adequate analgesia with PCA. Both patients and nurses face a steep learning curve in using PCA for management of procedural pain in burn care.

Burns in the disabled

A retrospective analysis of 812 patients admitted to the Ross Tilley Burn Centre between 1984 and 1992 resulted in 37 cases of burn injuries which were directly related to premorbid disabilities. The majority of these burns (83.8 per cent) occurred in the patient's home, most commonly as scald injuries in the bath tub, the shower, or following hot water spills. Nineteen patients were male, 17 were female. The median age was 58 years. Six patients had spinal cord disorders: four had traumatic cord damage, two had spina bifida. Six patients had seizure disorders. Five of these patients had been taking anti-seizure medications, but all had subtherapeutic blood levels on admission to hospital. Two patients had diabetes mellitus with peripheral neuropathies. Thirteen patients had four miscellaneous neurological disorders, including: tardive dyskinesia (two), CVA (four), Parkinson's disease (two), Alzheimer's disease (two), cerebral palsy (one), multiple sclerosis (one) and blindness (one). Three patients had a diagnosis of syncope. Two patients had emphysema, and four were morbidly obese. The average length of stay (LOS) for the disabled patients was 27.6 days for a median burn size of 10 per cent body surface area (BSA), compared to an average LOS for the general population of 25.7 days for a larger median burn size of 21 per cent BSA. The mortality rate was also much higher in the disabled population (22.2 per cent vs. 6.0 per cent). Most of these burn injuries were preventable. A series of burn prevention guidelines is presented, in an attempt to reduce the incidence of these burn injuries in disabled patients.

Assessment of the fluorescein dye test for prediction of skin flap viability in pigs

The visual fluorescein dye test for prediction of actual skin flap viability was evaluated in pigs. Two delayed random (4 X 10 cm) and arterial (4 X 20 cm) skin flaps were constructed on one flank of a pig, and four mirror-image skin flaps were raised acutely on the other flank of the same pig. Sodium fluorescein dye (15 mg/kg) was injected intravenously 1 and 18 hr after raising of flaps. The maximum length and area of dye stain in these flaps (N = 24) were assessed under Wood's lamp illumination, 15 min after dye injection. The actual maximum lengths and areas of skin survival of these flaps in the same pig were measured 7 days postoperatively. It was observed that visual fluorescein dye test performed 1 hr after surgery significantly (P less than 0.05) underestimated the maximum length and area of actual skin survival. On the other hand, when the fluorescein dye test was performed 18 hr postoperatively, the maximum length of dye stain and the maximum length of actual skin viability were highly correlated (r = 0.97, N = 24, P less than 0.01). Their mean values were similar (10.6 +/- 0.8 vs 10.8 +/- 0.7 cm, mean +/- SEM), and their mean coefficient of variation was 5.6 +/- 1.6%. Similarly, there was a high degree of correlation (r = 0.89, N = 24, P less than 0.01) between the maximum area of dye stain and actual skin flap viability. Their mean values were similar (68.3 +/- 4.5 vs 71.8 +/- 3.9%), and their mean coefficient of variation was 8.7 +/- 2.4%.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of glucocorticoid treatment on skin capillary blood flow and viability in cutaneous and myocutaneous flaps in the pig

The effect of methylprednisolone treatment on skin-flap viability and capillary blood flow was studied in a series of four experiments. Intramuscular methylprednisolone injections (30 mg/kg per day), given in single or divided doses preoperatively or postoperatively, had no effect in augmenting skin viability in arterialized cutaneous, myocutaneous, or random skin flaps compared with the control. Capillary blood flow was studied in arterial buttock flaps and latissimus dorsi myocutaneous flaps raised on animals treated preoperatively with methylprednisolone or saline (control), and no significant difference in capillary blood flow was noted between the treatment and control flaps. It was concluded that methylprednisolone has no significant therapeutic effect either in increasing flap viability or in increasing capillary blood flow in skin flaps in pigs.

Pharmacologic action of isoxsuprine in cutaneous and myocutaneous flaps

The therapeutic effects of isoxsuprine on skin capillary blood flow and viability were studied in arterial buttock flaps, latissimus dorsi myocutaneous flaps, and random skin flaps in pigs. It was observed that parenteral isoxsuprine increased capillary blood flow to the skin of arterial buttock flaps and the skin and muscle of latissimus dorsi myocutaneous flaps in a dose-response manner, with a maximum vascular effect observed at 1.0 mg/kg. However, this maximum effective dose of isoxsuprine did not have any significant effect on skin viability in the cutaneous and myocutaneous flaps compared with the control. Examination of the distribution of capillary blood flow within the flaps at varying distances from the pedicle revealed that isoxsuprine did not increase capillary blood flow or perfusion distance in the distal portion of the skin of arterial buttock flaps, latissimus dorsi myocutaneous flaps, and random skin flaps. The increased capillary blood flow as a result of isoxsuprine treatment was limited only to the arterial portion of the arterial buttock flaps and latissimus dorsi flaps. Therefore, it is concluded that isoxsuprine alone is not effective in augmentation of skin viability in cutaneous and myocutaneous flaps. The pharmacologic action of isoxsuprine on the vasculature in the skin and muscle of flaps was also discussed.

Assessment of microsphere technique for measurement of capillary blood flow in random skin flaps in pigs

In this technical paper, we reviewed the theory and methodology of the radioactive microsphere technique for determination of cardiac output and regional blood flow. Furthermore, we described two experiments conducted to assess this technique for measurement of capillary blood flow in skin-flap research. Our experimental data thus far indicated that the radioactive microsphere technique provided highly reproducible measurements for determination of capillary blood flow in 4 X 10 cm acute and delayed random skin flaps constructed in pigs. The advantages and disadvantages of this laboratory technique were also discussed.

Ursodeoxycholic acid for the dissolution of radiolucent gall bladder stones

In a prospective dosage response study of 84 patients with radiolucent gall bladder stones treated with ursodeoxycholic acid (UDCA), a dose of 500 mg daily was as effective as 1,000 mg daily. Complete dissolution of stones was achieved in 9 of 31 patients (29%) treated for at least 6 months with the lower dose, and in 7 of 33 patients (21%) on the higher dose. 4 patients in each group continue on treatment having shown partial gall-stone dissolution. When the two dosage groups were considered together, small stones dissolved more readily than larger ones and, after allowance for stone size, success rates were equal in obese and non-obese patients. Treatment with UDCA was well tolerated and significant adverse effects were not encountered.

Respiratory arrest in familial hemiplegic migraine: a clinical and neuropathological study

We describe a fatal case of familial hemiplegic migraine. A transient respiratory arrest in this patient led to a persistent "vegetative state," culminating in death four months later. Neuropathological findings included deep microinfarcts in the basal ganglia and a remarkable sparing of brain-stem nuclei associated with the function of respiration.