Infiltration of the abdominal wall with local anaesthetic after total abdominal hysterectomy has no opioid-sparing effect.
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We have measured the effect of infiltration of the deep and superficial layers of the abdominal wound on morphine consumption and pain for 48 h after operation, in 40 patients undergoing total abdominal hysterectomy, in a double-blind randomized study. Patients received wound infiltration with 0.9% normal saline 40 ml or 40 ml of 0.25% bupivacaine with epinephrine 1:200,000. There were no significant differences between groups in morphine consumption, linear analogue scores for pain at rest or on movement, nausea or sedation during the first 48 h after operation. We conclude that infiltration of the deep and superficial layers of the wound of a Pfannenstiel incision with local anaesthetic solution did not confer additional analgesia in patients undergoing major gynaecological surgery. (+info)
Responses of the anterolateral abdominal muscles during cough and expiratory threshold loading in the cat.
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The present study was conducted to determine the pattern of activation of the anterolateral abdominal muscles during the cough reflex. Electromyograms (EMGs) of the rectus abdominis, external oblique, internal oblique, transversus abdominis, and parasternal muscles were recorded along with gastric pressure in anesthetized cats. Cough was produced by mechanical stimulation of the lumen of the intrathoracic trachea or larynx. The pattern of EMG activation of these muscles during cough was compared with that during graded expiratory threshold loading (ETL; 1-30 cmH(2)O). ETL elicited differential recruitment of abdominal muscle EMG activity (transversus abdominis > internal oblique > rectus abdominis congruent with external oblique). In contrast, both laryngeal and tracheobronchial cough resulted in simultaneous activation of all four anterolateral abdominal muscles with peak EMG amplitudes 3- to 10-fold greater than those observed during the largest ETL. Gastric pressures during laryngeal and tracheobronchial cough were at least eightfold greater than those produced by the largest ETL. These results suggest that, unlike their behavior during expiratory loading, the anterolateral abdominal muscles act as a unit during cough. (+info)
Pelvic aspiration in the American alligator (Alligator mississippiensis).
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The pelvis of crocodilians is highly derived in that the pubic bones are isolated from the acetabulum and are attached to the ischia via moveable joints. We examined the possible role of this unusual morphology in lung ventilation by measuring ventilation, abdominal pressure and the electrical activity of several abdominal and pelvic muscles in the American alligator (Alligator mississippiensis). We found that the activity of two pelvic muscles, the ischiopubis and ischiotruncus muscles, was correlated with inspiration; these muscles rotate the pubes ventrally and thereby increase abdominal volume. During expiration, contraction of the rectus abdominis and transversus abdominis rotates the pubes dorsally. We suggest that this mechanism facilitates diaphragmatic breathing by creating space for caudal displacement of the viscera during inspiration. Because birds also use a dorso-ventral movement of the pelvis to effect ventilation, some form of pelvic aspiration may be plesiomorphic for archosaurs. (+info)
Effect of intraperitoneal pressures on tissue water of the abdominal muscle.
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A major factor that affects solute and water transport through tissue is the state of tissue hydration. The amount of interstitial water directly affects the transport coefficients for both diffusion and convection. To investigate the effect of simultaneous exposure of tissue to hydrostatic and osmotic pressures on the state of tissue hydration and the pattern of distribution of tissue water, we dialyzed rats with isotonic (290 mosmol/kg) or hypertonic (510 mosmol/kg) solution at intraperitoneal pressures (P(ip)) between 0 and 6 mmHg, and we infused isotopic markers intravenously and determined their equilibrium distribution volumes (V(D)) in the anterior abdominal muscle (AAM) by quantitative autoradiography. Total tissue water volume (theta(TW)) was determined from dry-to-wet weight ratios. theta(urea), the V(D) of [(14)C]urea, equals the sum of the extracellular water volume (theta(EC), V(D) of [(14)C]mannitol) and intracellular water volume (theta(IC) = theta(urea) - theta(EC)). If theta(if) = interstitial water volume and theta(IV) = vascular water volume (V(D) of (131)I-labeled IgG), then theta(EC) = theta(if) + theta(IV). AAM hydrostatic pressure profiles were measured by a micropipette/servo-null system and demonstrated that elevation of P(ip) above 3 mmHg significantly (P < 0.05) increases mean tissue pressure (P(T)) to the same level regardless of intraperitoneal osmolality. The increase in P(T) resulted in a nonlinear tissue expansion primarily in the interstitium regardless of osmolality. From 0 to 6 mmHg, theta(if) (in ml/g dry tissue) increased from 0.59 +/- 0.02 to 1.7 +/- 0.05 and to 1.5 +/- 0.05 after isotonic and hypertonic dialysis, respectively, whereas theta(IC) increased from 2.8 +/- 0.08 to 3.0 +/- 0.1 after isotonic dialysis and decreased to 2.6 +/- 0.1 after hypertonic dialysis. After dialysis at 6 mmHg with isotonic or hypertonic solutions, theta(IV) increased from 0.034 +/- 0.001 to 0. 049 +/- 0.001 and 0.042 +/- 0.002, respectively. theta(urea) during hypertonic dialysis at P(ip) between 0 and 6 mmHg increased in a nonlinear fashion (F = 26.3, P < 0.001), whereas theta(IC) invariably decreased (F = 11.1, P < 0.001) and theta(if) doubled from its control value at low P(ip). In conclusion, elevation of intraperitoneal hydrostatic pressure causes tissue expansion, primarily in interstitium, irrespective of osmolality of the bathing solution. Tissue hydrostatic pressure is therefore the primary determinant of tissue properties with respect to hydration, which in turn affects diffusive and convective transport. (+info)
Abdominal muscle response during curl-ups on both stable and labile surfaces.
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BACKGROUND AND PURPOSE: With the current interest in stability training for the injured low back, the use of labile (movable) surfaces, underneath the subject, to challenge the motor control system is becoming more popular. Little is known about the modulating effects of these surfaces on muscle activity. The purpose of this study was to establish the degree of modulating influence of the type of surface (whether stable or labile) on the mechanics of the abdominal wall. In this study, the amplitude of muscle activity together with the way that the muscles coactivated due to the type of surface under the subject were of interest. SUBJECTS: Eight men (mean age=23.3 years [SD=4.3], mean height=177.6 cm [SD=3.4], mean weight=72.6 kg [SD=8.7]) volunteered to participate in the study. All subjects were in good health and reported no incidence of acute or chronic low back injury or prolonged back pain prior to this experiment. METHODS: All subjects were requested to perform 4 different curl-up exercises-1 on a stable surface and the other 3 on varying labile surfaces. Electromyographic signals were recorded from 4 different abdominal sites on the right and left sides of the body and normalized to maximal voluntary contraction (MVC) amplitudes. RESULTS: Performing curl-up exercises on labile surfaces increased abdominal muscle activity (eg, for curl-up on a stable surface, rectus abdominis muscle activity was 21% of MVC and external oblique muscle activity was 5% of MVC; for curl-up with the upper torso on a labile ball, rectus abdominis muscle activity was 35% of MVC and external oblique muscle activity was 10% of MVC). Furthermore, it appears that increases in external oblique muscle activity were larger than those of other abdominal muscles. CONCLUSION AND DISCUSSION: Performing curl-ups on labile surfaces changes both the level of muscle activity and the way that the muscles coactivate to stabilize the spine and the whole body. This finding suggests a much higher demand on the motor control system, which may be desirable for specific stages in a rehabilitation program. (+info)
Functional TSH receptor in human abdominal preadipocytes and orbital fibroblasts.
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Controversy continues about whether, and to what levels of abundance, thyroid-stimulating hormone receptors (TSHR) are found in human tissues other than the thyroid gland. Restricted expression to the thyroid and orbit would suggest that TSHR represents the target autoantigen in thyroid-associated ophthalmopathy. A more generalized pattern of tissue expression would be inconsistent with TSHR acting as the autoantigen that is solely responsible for selectively targeting the immune system to the orbit. We have detected TSHR mRNA in human abdominal adipose tissue by Northern blot analysis. TSHR protein was also detected, by immunoblotting with two different antibodies, in preadipocytes isolated from human abdominal subcutaneous and omental adipose tissue and in derivative adipocytes differentiated in primary culture. Preadipocytes treated with thyroid-stimulating hormone (TSH) exhibited a sevenfold increase in the activity of p70 S6 kinase, a serine/threonine kinase recently recognized as a downstream target of TSHR in thyroid cells. Activation of p70 S6 kinase by TSH was also observed in orbital fibroblasts. Thus TSHR protein expression is found in fibroblasts from several anatomic locations, suggesting that factors other than site-limited TSHR expression must be involved in restricting the distribution of Graves' disease manifestations. Furthermore, the presence of functional TSHR in preadipocytes raises the possibility of a novel role for TSHR signaling in adipose tissue development. (+info)
A multicentric comparison of transabdominal versus totally extraperitoneal laparoscopic hernia repair using PARIETEX meshes.
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The authors report a series of 1972 inguinal hernias treated between 1993 and 1997 by the insertion of a PARIETEX mesh via either a transabdominal-preperitoneal (TAPP) (1,290 procedures) or a totally extraperitoneal TEP approach (682 procedures). Pain scores were equivalent in both groups, while the hospital stay and time to return to normal activity was lower in the TEP group than in the TAPP group (p<0.001). In both groups, the average incidence of the total reported events (complications) was around 10% with no statistical difference. This ratio seemed to compare favorably to previously published reports. Chronic pain was extremely rare (0.6% and 0.7% in the TAPP and TEP groups, respectively). Whatever the approach was, sepsis was also very rare (1/1,526 laparoscopic procedures). These findings illustrate the local tolerance of the mesh. Recurrence rates were below 1% with no statistical difference between groups. This retrospective study demonstrates the clinically apparent local tolerance of this type of mesh. Prospective and long-term clinical results will be necessary to demonstrate that the optimized short-term tolerance of PARIETEX mesh will influence the long term functional results. (+info)
Diagnostic ultrasound activation of contrast agent gas bodies induces capillary rupture in mice.
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Interaction of diagnostic ultrasound with gas bodies produces a useful contrast effect in medical images, but the same interaction also represents a mechanism for bioeffects. Anesthetized hairless mice were scanned by using a 2.5-MHz transducer (610-ns pulses with 3.6-kHz repetition frequency and 61-Hz frame rate) after injection of Optison and Evans blue dye. Petechial hemorrhages (PHs) in intestine and abdominal muscle were counted 15 min after exposure to characterize capillary rupture, and Evans blue extravasation was evaluated in samples of muscle tissue. For 5 ml small middle dotkg(-1) contrast agent and exposure to 10 alternating 10-s on and off periods, PH counts in muscle were approximately proportional to the square of peak negative pressure amplitude and were statistically significant above 0.64 MPa. PH counts in intestine and Evans blue extravasation into muscle tissue were significant above 1. 0 MPa. The PH effect in muscle was proportional to contrast dose and was statistically significant for the lowest dose of 0.05 ml small middle dotkg(-1). The effects decreased nearly to sham levels if the exposure was delayed 5 min. The PH effect in abdominal muscle was significant and statistically indistinguishable for uninterrupted 100-s exposure, 10-s exposure, 100 scans repeated at 1 Hz, and even for a single scan. The results confirms a previous report of PH induction by diagnostic ultrasound with contrast agent in mammalian skeletal muscle [Skyba, D. M., Price, R. J., Linka, A. Z., Skalak, T. C. & Kaul, S. (1998) Circulation 98, 290-293]. (+info)