PubMed Health⌕ Search

Biomedical subjects

U Balldin

Publications and source records attributed to U Balldin.

7 recordsLinked to original sources

Arm pain among Swedish fighter pilots during +Gz flight and centrifuge exposures.

BACKGROUND: The purpose was to survey the occurrence of arm pain among Swedish fighter or test pilots in connection with exposures to high +Gz load when flying or performing centrifuge tests. HYPOTHESIS: +Gz induced arm pain occurs in connection with high +Gz loads in flight as well as in centrifuge tests of high performance fighter pilots. METHODS: A questionnaire was used for data collection regarding +Gz induced arm pain. Respondents were 35 Swedish Air Force Viggen and Gripen fighter pilots who had previously participated as subjects in centrifuge tests between 1990 and 1995 at Brooks Air Force Base, TX, either with the standard anti-G suit or with extended coverage anti-G suit with pressure breathing during +Gz. RESULTS: Of the respondents, 55% reported that they had experienced arm pain during flight at least once and 42% experienced it more than three times. However, arm pain was more common in the centrifuge tests (82% once; and 42% more than 3 times). CONCLUSIONS: Presence of arm pain during high performance fighter aircraft flights is a phenomenon that should be taken into consideration when designing high performance aircraft or +Gz protective equipment.

Adult↗

Effects of triglycyl-lysine-vasopressin on cardiovascular responses to orthostatic stress.

The influence of triglycyl-lysine-vasopressin (TGLVP) on cardiovascular responses to orthostatic stress was studied. Arterial pressures, heart rate (HR) and stroke volume (SV) were measured in eight healthy males subjected to 20 min 70 degrees head-up tilt. On different days they received either 0.01 mg/kg b.w. of TGLVP or a corresponding volume of 0.9% saline i.v. after 15 min supine rest. After the drug injection, in supine subjects, HR had decreased from 58 to 50 beats min-1, total peripheral resistance (TPR) was elevated by 29%, systolic (SAP) and diastolic pressure (DAP) had increased by 7 and 8 mmHg, respectively. During tilt, values for HR and SAP were similar with and without TGLVP whereas DAP and MAP were elevated 8 and 7 mmHg, respectively, by the drug. 4-8 min into the tilt, TGLVP caused an 8% sustained curtailment of SV. Both with and without the drug TPR increased by about 30% in response to head-up tilt. Thus, the marked peripheral arteriolar constriction after vasopressin in the supine position was not affected by head-up tilt. Tilting also abolished the drug-induced elevation in SAP, most likely explained by the reduction in SV. Although TPR was markedly increased by TGLVP during head-up tilt, reflected in the behaviour of DAP, the response of SV speaks against any beneficial effect of this drug on orthostatic tolerance in healthy subjects.

Adult↗

Orthostatic reactions during recovery from exhaustive exercise of short duration.

We studied the responses of six healthy volunteers to standard 70 degrees head-up tilt tests before exhaustive exercise of short duration (control) and after 5, 25, 50, 80, and 110 min of recovery, all tests lasting for 6 min except when impending syncope (IS) necessitated premature termination of a test. Marked impairment of orthostatic tolerance was apparent during the first half-hour of recovery as manifested by symptoms of IS in five subjects in one or both of the first two postexercise tilt tests. In none of the subjects who developed symptoms of IS did central venous pressure fall to a lower level than it did in the control test. From the central venous and arterial pressure reactions we conclude that when IS developed, declining systematic resistance rather than diminished cardiac filling was the responsive factor. The increased tendency for orthostatic collapse occurred during a period of recovery marked by persistent postexercise acidemia and hyperthermia suggesting interference of these conditions and associated events with the normal ability to vasoconstrict during orthostasis.

Adult↗

Preventive effect of a vasodilator on the occurrence of decompression sickness in rabbits.

The effect of terbutaline on the occurrence of decompression sickness was studied in seven rabbits. Terbutaline is a vasodilator, a sympathomimetic beta2-receptor stimulator. The rabbits were given a hyperbaric exposition at 2 ATA followed by oxygen breathing at 1 ATA and a hypobaric exposition at 0.2 ATA. Each rabbit got a hyperbaric exposition long enough for symptoms of decompression sickness to occur at the hypobaric exposition. With a time interval of at least 1 week, each rabbit received an identical pressure exposition, except that terbutaline was injected intravenously at the beginning of the denitrogenation period at 1 ATA. Of the seven experiments with the drug, only one case of decompression sickness occurred and with a delayed appearance. This may be compared to rapid-appearing decompression sickness in all cases in the control series. The results may be of importance in diving routines and, possibly, in the treatment of decompression sickness.

Animals↗