Biomedical subjects

P A Armstrong

Publications and source records attributed to P A Armstrong.

12 recordsLinked to original sources

PubMed1999

Diaphragmatic hernia seen as a late complication of laparoscopic cholecystectomy.

Laparoscopic surgery has emerged as the standard of care for the elective operative management of symptomatic gallbladder disease. The surgical literature is now beginning to accumulate sufficient case numbers that more clearly define the associated morbidity of this type of surgery. This article reports an instance of iatrogenic injury to the right muscular hemidiaphragm and subsequent hernia after laparoscopic cholecystectomy.

Cholecystectomy, Laparoscopic↗

PubMed1998

Improved selection criteria for ordering stat venous ultrasounds from the emergency department.

BACKGROUND: The accuracy and convenience of venous ultrasound (VU) to exclude deep vein thrombosis (DVT) has led to indiscriminate use and low positive yield rates. METHODS: A total of 256 patients were referred from our emergency department (ED) for stat VU during a 2-year period (1995 to 1996). The VUs were interpreted as normal in 198 (77%). Positive findings were discovered in 58 (23%), with DVT accounting for 43 (17%). Retrospective multivariant analysis was used to identify predictive indicators. RESULTS: Unilateral leg swelling/edema identified 36 of 40 (90%) patients with DVT and 8 of 10 (80%) with other thrombotic disorders (saphenous and/or chronic venous thrombosis). A history of leg pain with prior DVT or recent trauma < or =3 days' duration increased DVT duration to 98% (39 of 40). Using these criteria, a 47% charge reduction would have been recognized. CONCLUSIONS: Improving ED screening criteria can safely increase yield rate and reduce charges with minimal loss of VU sensitivity.

Adolescent↗

PubMed1998

Reduced use of resources by early tracheostomy in ventilator-dependent patients with blunt trauma.

BACKGROUND: Early tracheostomy has been advocated for ventilator-dependent patients with blunt trauma, but its advantages have not been examined critically. METHODS: We retrospectively reviewed our experience with all patients with blunt trauma undergoing tracheostomy during the 6-year period from 1990 to 1995. Patients undergoing tracheostomy within the first 6 days of hospitalization were designated as early recipients (ET) and those undergoing the procedure at 7 or more days were defined as late recipients (LT). RESULTS: The entire study group consisted of 157 patients. The ET group contained 62 patients and the LT group contained 95 patients. No statistical differences were noted between the 2 groups with respect to sex distribution, injury severity scores, probability of survival scores, or mortality rates. The mean stay in the intensive care unit for the ET group was 15 days compared with 29 days for the LT group (P < or = .001). The mean total hospital stay for the ET group was 33 days compared with 68 days for the LT group (P < or = .001). The mean estimated per-patient hospital charges for only room and ventilator care were $36,609 for the ET group compared with $73,714 for the LT group. CONCLUSIONS: ET in this patient group resulted in significantly lowered use of resources with no adverse effect on outcome.

Adult↗

PubMed1993

The effect of electric field gradient asymmetry on motionally averaged spin-1 powder patterns.

The effect of an asymmetric electric field gradient tensor on anisotropic NMR spectra of spin-1 nuclei is investigated for fast molecular rotations and 2-site jump processes. When molecular rotations are fast, continuous, and complete, the peak-to-peak splitting of motionally averaged spin-1 NMR spectra can depend significantly on the inherent electric field gradient asymmetry, eta, for eta > or = 0.05. Parameters describing low-symmetry molecular motion which are extracted from fitting experimental data depend strongly upon eta. One implication of these phenomena is that even the modest electric field gradient asymmetry around deuterons in covalent bonds can contribute considerably to motionally averaged lineshapes, especially when molecular motions are not highly symmetric.

Electricity↗

PubMed1976